Chesapeake Bay future conditions report

[From the U.S. Government Printing Office, www.gpo.gov]

'oa sta I
Zone
Information
Center VOLUME 11
NO

M
a
at win

lWk',-Z0NE
TER

UY 4-

4 PEA
"T

AMC -M
Xakle
'M'
:E Ir GMI)FIlom �4y

U S DEPARTMENT OF COMMERCE NOAA
COASTAL SERVICES CENTER
2234 SOUTH HOBSON AVENUE
CHARLESTON SC 29405-2413

10
PREFACE UlASTAL ZON.IE
INFORMOON CENTER
The Corps of Engineersf comprehensive study of Chesapeake Bay is being
accomplished in three distinct developmental stages or phases. Each
of these phases is responsive to one of the following stated objectives
of the study program.

1. To assess the existing physical, chemical, biological, economic
and environmental conditions of Chesapeake Bay and its related land
resources.

2. To project the future water resources needs of Chesapeake Bay
to the year 2020.

3. To formulate and.recommend solutions to priority problems
using the Chesapeake Bay Hydraulic Model.

In response to the first objective of the study, the initial or
inventory phase.of the program was completed in 1973 and the findings
were published in a document titled Chesapeake Bay Existing Conditions
Re2ort. Included in this seven-volume report is a description of the
existing physical, economic, social, biological and environmental con-
.ditions of Chesapeake Bay. This was the first published report that
presented a comprehensive.survey of the entire Bay Region and treated
the Chesapeake Bay as a single entity. Most importantly, the report
contains the historical records and basic data required to project
the future demands'on the Bay and to assess the ability of the resource
to meet those demands..

In response to the second objective of the study, the findings of the
second or future projections phase of the program are provided in
this the Ches@!Eeake Bay Future Conditions Report. The primary focus
of this report is the projection of water resources needs to the year
2020 and the identification of the problems and conflicts which would
@result from the unrestrained growth and use of the Bay's resources.
This report, therefore, provides the basic information necessary to
proceed into the next or plan formulation.phese of the program. It
should be emphasized that, by design, this report addresses only the
water resources related needs and problems. No attempt has been made
to identify or analyze solutions to specific problems. Solutions to
priority problems will be evaluated in the third phase of the program
and the findings will be published in subsequent reports.

The Chesapeake Bay Future Conditions Report consists of a summary
-document and 16 supporting appendices. Appendices I and 2 are general
background documents containing information describing the history and
conduct of the study and the manner in which the study was coordinated
with the various Federal and State agencies, scientific institutions
ugh 15 each contain information on
and the public. Append-Ices 3 thro
specific water and related land resource uses to include an inventory

Y Appendix 15
ftoverty Of.CSC Library i

of the present status and expected future needs and problems.
Appendix 16 focuses on the formulation of the initial testing program
for the Chesapeake Bay Hydraulic Model. Included in this appendix is
a description of the%hydraulic model, a list of problems considered
for inclusion.in-fhelin'itial testing program and a detailed description
of the selected first year,model studies program.

The published volumes of the Ches eake Bay Future Conditions Report
include:

Volume Number Appendix Number and Title

I Summary Report

2 1 Study Organization, Coord ination and
History
2 -Public Participation and Information

3 3 - Economic and Social Profile

4 4 - Water-Related Land Resources

5 5 - Municipal and Industrial Water Supply
6 - Agricultural Water Supply

6 7 - Water Quality

7 8 - Recreation

8 9 - Navigation
10 - Flood Control
11 - Shoreline Erosion.

9 12 - Fish and Wildlife

10 13 - Power
14 - Noxious Weeds

11 15 - Biota

12 16 Hydraulic Model Testing

Appendix 15
ii

CHESAPEAKE BAY FUTURE CONDITIONS REPORT

APPENDIX 15 COASTAL ZONE
BIOTA INFORUTiON C'E"WER

TABLE OF CONTENTS

Chapter Page

I THE STUDY AND THE REPORT 1

Authority 2
Purpose 3
Scope 4
Supporting Studies 6
Study Participation and Coordination 7

II BIOTA IN THE CHESAPEAKE BAY REGION 9

Description of the Region 9
The Chesapeake Bay Region 10
Resources 12
History 13
Descriptive Publications 14
Present Status Summary 15

III ECOLOGICAL CONCEPTS AND ENVIRONMENTAL
FACTORS 23

Ecological Concepts 24
Ecosystems 24
Communities 25
Limiting Factors 30
Environmental Factors 32
Physico-Chemical Factors 33
Biological Factors 54

IV IMPORTANT SPECIES IDENTIFICATION 61

V BIOLOGICAL SUMMARIES OF SIGNIFICANT
BAY ORGANISMS 71

Diatoms 73
Silver Hydroid 85
Green Anemone 88
Blood Worm 92
Coot Clam,Dwarf Surf Clam 96

Appendix 15
iii

TABLE OF CONTENTS (cont'd)

Chapter Page

Brackish-Water Clam 99
Copepod 105
Glass or Grass Shrimp 110
Sand Shrimp 113
Mud Crab 116
Blue-Backed Herring 121
Mummichog 127
White Perch 144
Spot 158
Northern Puffer 164
Snapping Turtle 168
Diamondback Terrapin 174,
Whistling Swan 179
Canada Goose 182
Black Duck 185
Bufferhead 188
Oldsquaw 191
Ruddy Duck 193
Osprey 195

VI ECOLOGY OF SELECTED CHESAPEAKE BAY
COMMUNITIES 199

Status of Knowledge 199
Chesapeake Bay Community Structure 201
Zostera (eelgrass) Community 2Q5
Oyster Community 250
Miscellaneous Communities 293
Literature Cited (for Chapters I,
III, VI, VIII) 304

VII WATER QUALITY STANDARDS AND CRITERIA 325

Introduction 327
Identification of Relevant Standards
and Criteria 332
Review of Standards and Criteria
Related to Oil 364
Review of Standards and Criteria
Related to Chlorine 380
Conclusions 386
Literature Cited 387

Appendix 15
iv

TABLE OF CONTENTS _(cont'd)

Chapter Page

VIII PROBLEM AREAS AND FUTURE REQUIREMENTS 393

Problem Setting 398
Environmental Quality Problems 395
Future Needs and Requirements 407
Model Testing Applications 408

GLOSSARY 415

LIST OF TABLES

Nuniber Title Page

15-1 Taxonomic Parallels Between Species
of Chesapeake Bay, San Francisco
-Bay, and European Estuaries 28

15-2 List of Scientists Responding to
'Important Species" Questionnaire 62

15-3 Important Chesapeake Bay Species 65

15-4 Literature Summary of Chaetoceros
Species in Chesapeake Bay, With
Spatial and Temporal Distribution 74

15-5 Classifications of Approximate Geographic
Divisions, Salinity Ranges, Types, and
Distribution of Organisms in Estuaries 202

15-6 Community Structure in Chesapeake Bay
by Salinity Zones 206

15-7 Eelgrass Frequency Distribution, 1971,
1972, 1973 211

15-8 Elemental Composition of Eelgrass 224

15-9 Organisms of the Chesapeake Eelgrass
Community 234

15-10 Macroalgae Observed on Zostera Leaves 240

15-11 Kikuchis' Classification of Fishes
Associated with Zostera 244

Appendix 15
v

LIST OF TABLES (cont'd)

Number Title Page

15-12 Species Occurrence Before and After
Disappearance of Eelgrass 247

15-13 Faunal Composition of an Oyster Community 262

15-14 Organisms*Observed Associated with Oyster
Bars in the Potomac River 271

15-15 Organisms Found in Association with
Oysters in the York River 274

15-16 Benthic Fauna in Lower Patuxent River,
Maryland 276

15-17 Common Fishes of Upper Chesapeake Bay
by Salinity Zone 296

15-18 Summary of Proposed EPA Water Quality
Criteria for Aquatic Life 334

15-19 Summary of Proposed EPA Water Quality
Criteria for Wildlife 341

15-20 Proposed EPA Water Quality Criteria
for Recreational Waters 343

15-21 Industrial Categories and Effluent
Limitations 346

15-22 Effluent-Limitations to be Achieved
by All Secondary Federally Financed
Treatment Plants 351

15-23 Proposed EPA Toxic Pollutant Effluent
Standards 352

15-24 Summary of EPA Criteria for the Eval-
uation of Permit Applications for
Ocean Dumping 353

15-25 Water Quality Standards for the State
of Maryland 357

15-26 Water Quality Standards for the Common-
wealth of Virginia 362

15-27 Effluent Limitation Guidelines for Oil
and Grease Discharges for the Petroleum
Refining Industry 367

Appendix 15
vi

LIST OF FIGURES (cont'd)

Number Title Page

15-28 Feeding Interrelationships of Animals
in the Low and High Salt Marsh 302

15-29 Relationship of Water Quality Criteria
and Standards 328

15-30 Major Municipal Sewage Discharges in
Chesapeake Bay 375

15-31 Residual Chlorine in the Lower James
Estuary 383

Areas of Pollution in Chesapeake Bay 400

15-33 Exchange of Nutrients Between Marsh
and Sea 404

15-34 Model Studies Applicable to Biological
Problems 411

LIST OF ATTACHMENTS

Number Title

15-A Letter and Questionnaire Circulated to
Determine "Important" Bay Area Species

15-B Inventory of Wetland Communities

15-C Inventory and Zonation of Benthic
Communities

15-D Questionnaire Package and Written
Responses from Bay Area Scientists
Concerning Uses for the Bay Model

Appendix 15
ix

LIST OF TABLES (cont'dj

Number Title Page

15-28 Mass Emission of "Oil and Grease" into
Tidal Waters of Southeastern Virginia 370

15-29 Summary of Estimated Annual Inputs of
Petroleum to Chesapeake Bay 373

15-30 Causes of Biological Problems in
Chesapeake Bay 398

15-31 Areas of Particular Biological Concern
in Chesapeake Bay 399

15-32 Capabilities of Technology for Control
of Various Pollutants 406

15-33 Ranking of Biological Applications
for the Bay Model 412

LIST OF FIGURES

Number Title Page

15-1 Chesapeake Bay Study Ar ea 5

15-2 Physiography of the Bay Area 11

15-3 Numerical Rank of Predominant Plant Taxon 16

15-4 Parallelism Between the Arctic, Boreal,
and Northeast Pacific Macoma
Communities 26

15-5 Schematic Diagram of the Effects of
Stress on Energy Flow in a Simple
Ecosystem -29

15-6 Diagram to Illustrate Limiting Factors
in the Bed of an Estuary 31

15-7 Plan of an Ideal Estuary 32

15-8 Distribution of Salinity at Low Water
in the Muddy Foreshore of an Estuary @37

15-9 Typical Surface Salinities in Chesapeake
Bay 40

Appendix 15
vii

LIST OF FIGURES (cont'd)

Number Title page

15-10 A Generalized Concept of Numbers of
Species in Relation to Salinity 42

15-11 Distribution of Dissolved Oxygen at a
Depth of Ten Feet 46,

15-12 Simplified Cycle of Phosphorus Transfor-
mation 52

15-13 The Organic Circulation of Nitrogen in
the-Ocean 53

15-14 Energy Flow Through an Aquatic Ecosystem 55

15-15 Components of a Plankton Based Food Chain 57

15-16 Salinity Zones of Chesapeake Bay 204

15-17 Distribution of Eelgrass in the
Chesapeake Bay 210

15-18 The Biogeochemical Cycle of Nutrient X 219

15-19 Circulation of Nitrogen in Seagrass
Ecosystem 220

15-20 Circulation of Phosphorus in Seagrass
Ecosystem 223

15-21 Progressive Development of Zosteramarina 226

15-22 Diagram of Progressive Development of
Ee1krass 228

15-23 Sites of Eelgrass Investigations by Marsh
(1970) and Orth (1971) 232

15-24 Trophic Relationships of Some Epifauna
of Chesapeake Bay 243

15-25 Sketch of an Oyster Clump from South Bay,
Near Port Isabel, Texas 251

15-26 Movements of Estuarine-Dependent Fish
Larvae and Juveniles Toward a Common
Low Salinity Nursery Area 299 4@

15-27 Interactions of Biotic and Physical
Effects in a Marshbordered Estuary 301
Appendix 13
viii

CHAPTER I

THE STUDY AND THE REPORT

The Chesapeake Bay Study developed through the need for
a complete and comprehensive investigation of the use and
control of the water and related land resources of
Chesapeake Bay. In the first phase of the Study, the
existing physical, biological, economic, social, and
environmental conditions and the present problem areas
in the Bay were identified and presented in the Chesa-
peake Bay Existing Conditions Report which was published
in 1973. The Future Conditions Report, of which this
appendix is a part, presents the findings of the second
or projections phase of the Study. As part of this
second phase-of tbe,.,,Study, projections of future needs
and problem areas, means to satisfy those needs, and
recommendations for future studies and hydraulic model
testing were developed for each of the resource cate-
gories evaluated. The results of this phase of the
Study constitute the next step toward the goal of devel-
oping a comprehensive water resource management program
for Chesapeake Bay.

The subject of this volume, Biota, focuses on the iden-
tification, characteristics, and importance of the biota
of the Chesapeake Bay Region. This appendix first
addresses how the Bay ecosystem works and how various
physical and chemical factors influence the system.
S6condly, an identification and discussion of both the
important species and communities in the Bay is provided.
Because of the importance of water quality to the Bay
biota, one chapter is devoted to identifying all Federal
and State water quality criteria and standards pertinent
to the Bay and assessing the impact of compliance with
these standards on the Bay ecosystem. Lastly,-this appen-
dix identifies present and future problems as they relate

Appendix 15

to the Bay biota and the future studies that are required
to meet the goal of developing a management plan for
Chesapeake Bay.

AUTHORITY

The authority for the Chesapeake Bay Study and/the
construction of the hydraulic model is contained in
Section 312 of the River and Harbor Act of 1965, adopted
27 October 1965:

(a) The Secretary of the Army, acting through
the Chief of Engineers', is authorized and
directed to make a complete investigation and
study of water utilization and control of the
Chesapeake Bay Basin, including the waters of
the Baltimore Harbor and including, but not
limited to, the following: navigation, fish-
eries, flood control, control of noxious
weeds, water pollution, water quality control,
beach erosion, and recreation. In ord -er to
carry out the purposes of this section, the
Secretary, acting through the Chief of Engin-
eers, shall construct, operate, and maintain
in the State of Maryland a hydraulic model
of the Chesapeake Bay Basin and associated
technical center. Such model and center may
be utilized, subject to such terms and con-
ditions as the Secretary deems necessary, by
any department, agency, or instrumentality
of the Federal Government or of the States
of Maryland, Virginia, and Pennsylvania, in
connection with any research, investigation,
or study being carried on by them of any
aspect of the Chesapeake Bay Basin. The
study authorized by this section shall be
given priority.

(b) There is authorized to be appropriated
not to exceed $6,000,000 to carry out this
section.

Appendix 15
2

An additional appropriation for the Study was provided
in Section 3 of the River Basin Monetary Authorization
Act of 1970, adopted 19 June 1970:

In addition to the previous authorization,
the completion of the Chesapeake Bay Basin
Comprehensive Study, Maryland, Virginia,
and Pennsylvania, authorized by the River
Irv and Harbor Act of 1965 is hereby authorized
at an estimated cost of $9,000,000.

As a result of Tropical Storm Agnes, which caused
extensive damage in Chesapeake Bay, Public Law 92-607,
the Supplemental Appropriation Act of 1973, signed by
the President on 31 October 1972, included $275,000
for additional studies of the impact of the storm on
Chesapeake Bay.

PURPOSE

Previously, measures taken to utilize and control the
water and related land resources of the Chesapeake Bay
Basin have generally been toward solving individual
problems. The Chesapeake Bay Study provides a compre-
hensive study of the entire Bay Area in order that the
most beneficial use be made of the water-related
resources. The major objectives of the Study are to:

a. Assess the existing physical, chemical, biological,
economic, and environmental conditions of Chesapeake Bay
and its water resources.

b. Project the future water resources needs of
Chesapeake Bay to the year 2020.

C. Identify the additional studies, to include
hydraulic model testsi that are needed to formulate a
water resources management program for the Bay-

The Chesapeake Bay Existing Conditions Report, published
in 1'973, met the first objective of the Study by present-
ing a detailed inventory of Chesapeake Bay and its water
resources. Divided into a summary and four supporting

Appendix 15
3

appendixes, the report presents an overview of the Bay
area and the economy; a.survey of the Bay's land resource
and its use; and a description of the Bay's life forms
and hydrodynamics.

The purpose of the Future Conditions Report is to provide
a format for presenfing the findings of the Chesapeake
Bay Study. Satisfying the last two objectives of the
Study, the report describes the present use of the resource,
presents the demands to be placed on the resource to the
year 2020, assesses the ability of the resource to meet
future demands, and identifies additional studies required
to develop a management plan for Chesapeake Bay.

The purpose of this Biota Appendix is to present the
findings of the Chesapeake Bay Study as it relates to
the biota in the Chesapeake Bay Region.

SCOPE

The scope of the Chesapeake Bay Study and Future Conditions
Report includes the multi-disciplinary fields of engineer-
ing and the socialphysical, and biological sciences. The
Study is being coordinated with all Federal, State, and
local agencies having an interest in Chesapeake Bay.
Included in the report are projections of demands and
potential problem areas to the year 2020 for each signi-
ficant resource category. All conclusions are based on
historical information supplied by the preparing agencies
having expertise in that field. In addition, the basic.
assumptions and methodologies are quantified for accuracy
in the sensitivity section. Only general means to satisfy
the projected resource needs are presented, as recommen-
dations for specific areas are beyond the scope of the
Study.

The geographical study area considered in the analysis
of the biota of Chesapeake Bay includes the waters of
Chesapeake Bay proper and its tributaries to the head of
tide as well as the contiguous land area as delineated
on Figure 15-1. The Study Area is consistent with the
Chesapeake Bay Estuary Area as defined for the overall
Study and encompasses those counties and independent cities
which border on or have a major influence on the Estuary.

Appendix 15
4

OUTicA

ALBANYID
ONOAWIC.",.-

MAM
'0316 TON
L -1-116. ,
g,odf,,d S. h. "i

/14TON

WILK S BARRE*
-@,-@".LLIAMSPPRTO C., , t
robll t@'
'? 'i SBURG
13.1
S@ROUD

PUNXSUTA...
ALT Ball. TrN
A*
to..
7 C..bol..d
LANC@ASTEV'
IJP
SOMERSET 0 Wfad HOW F-kii. Y.,k ..... . .. .........
hd- YORK
PA
-*HAGE
rMD
AtI.0

CLARKSBURG

Gr. JrE

SHI

HARRI NBU

S NTO4
efof Al.-I,

-H
hTI/
ed

GEND
j
DY AREA
j,h rk

NC MURFEESBAd.0

RGURE 15-1: Chesapeake Bay Study Area

Appendix 15
5

As part of the first or existing conditions phase of the
Chesapeake Bay Study, a checklist of the biota of the
Bay was prepared and taxa summaries for all major groups
with the exception of insects and spiders was also com-
piled. (A treatment of the vast numbers of insects and-
spiders was considered to be beyond the scope of the
Study.) This checklist and the summaries were published
in Volume II, Appendix C, of the Existing Conditions
Report. For this phase of the Study the 2,650 species
identified in the Existing Conditions Report were
screened and 126 species considered to be the most
important from a biological or commercial fisheries
standpoint were selected for more detailed study.
Within time and funding constraints these selected
species were then addressed in more detail as were
several key biological communities.

SUPPORTING STUDIES

This appendix was prepared and coordinated by the
Baltimore District, Corps of Engineers; however, all
technical segments as referenced were prepared by the
Chesapeake Research Consortium, Inc., under contract
to the Baltimore District. The Chesapeake Research
Consortium is composed of the Virginia Institute of
Marine Science, the Smithsonian Institution, the
Chesapeake Biological Laboratory of the University of
Maryland, and the Chesaapake Bay Institute of the
Johns Hopkins University. The Consortium also pre-
pared, under contract, the biological studies and
report included in Volume II, Appendix C, of the
Existing Conditions Report which should be considered
as a basic companion to the information presented in
this appendix. For a list of all the supporting studies
and reports that contributed to this appendix, the
Bibliography included in this appendix should be
consulted.

Appendix 15.
6

STUDY PARTICIPANTS AND COORDINATION

The magnitude of this Study, the large number of par-
ticipants, and the complex spectrum of problems requires
a high degree of coordination of the various study
activities. This Study was conceived and has developed
as a coordinated partnership between Federal, State,
and interested educational institutions. As explained
in Appendix 1 of this report, an Advisory Group, a
Steering Committee, and five Task Groups were formed
to coordinate and review the Study effort.

This appendix was reviewed by the Steering Committee.
The Steering Committee is responsible for reviewing
the work of other groups and bringing to their attention
any pertinent advances in water resources development or
the environmental sciences and making recommendations as
to their use. This group will also review plans for
scientific activities that may become a necessary adjunct
to this Study. The membership of this group includes
representatives from the following department or agencies.

Corps of Engineers (Chairman) Maryland
Energy Research and Development Virginia
Administration Delaware
Interior Pennsylvania
National Science Foundation District of Columbia
Smithsonian Institution
Commerce

Appendix 15
7

CHAPTER II

BIOTA IN THE CHESAPEAKE BAY REGION

It is the extraordinary extensiveness and diversity of
Chesapeake Bay which stands it apart as one of the most
productive estuaries on earth. The Bay provides vast
feeding, shelter and nursery grounds for fish, shellfish,
waterfowl and the myriad of other plant and animal forms
which inhabit the Region'. This chapter provides a
description of the Bay and its resources together with
an overview of the biota of the Region.

DESCRIPTION OF THE REGION

In order to better understand the organisms which
inhabit any area it is first necessary to have a basic
understanding of the area and its resources. This
section provides an overview of the Region and a short
history of how the present state of knowledge of the
Bay's biota was developed. Also included is an iden-
tification and discussion of some of the more signi-
ficant publications that address the biota of the Bay.

JV1

Appendix 15
9

THE CHESAPEAKE BAY REGION

Chesapeake Bay is the largest of the hundreds of estuaries
in the United States stretching nearly 200 miles from
Pennsylvania to North Carolina with a maximum width of
30 miles near the Maryland-Virginia border. The Bay with
its countless tidal tributaries has a total water surface
area of approximately 4,300 square miles and a tidal
shoreline of 7,300 miles. Fed by nine major river systems
and numerous small streams, the Bay's drainage basin covers
approximately 64,160 square miles and portions of six
states and the District of Columbia.

The physical composition and structure of the earth in
the Chesapeake Bay Region varies from the basically
flat, sedimentary Atlantic Coastal Plain Pr6vince to
the rocky, more rugged topography of the Piedmont
Plateau Province. As shown on Figure 15-2, these two
physiographic-geologic regions run roughly parallel
to the Atlantic Ocean and the Bay itself and adjoin
at the Fall Line.

The Chesapeake Bay, like other estuaries, is only a
short term feature on a geologic time scale. The Bay
is being rapidly filled with sediments from rivers
and shore erosion, the remains of organisms that inhabit
the Bay and sediments from the sea. The sources are
thus external, marginal and internal. On a system-wide
basis, the external sources are predominant, and the
rivers account for the vast majority of this input.
The characteristic mode of sediment transport both into
and within the estuarien portions of the Bay is as sus-
pended load.

The Bay is characterized by a generally moderate cli-
mate, due in a large part to the area's proximity to
the Atlantic Ocean. Variations occur, however, on a
local short term basis due to the large geographical
size of the Bay area. The average precipitation of
the area as a whole is 44 inches per year, with geo-
graphical variations from about 40 to 46 inches per
year. Snowfall included in the precipitation totals
averages about 13 inches per year and generally occurs
between November and March. The average temperature
fro the area is 570F; however, because of the wide
latitudinal area, the temperatures at the head of the
Bay average 550F, while at the mouth the average is
almost 600F.

Appendix 15
10

HARRISBURG

Y
BALTIM E.--
rev

IDOVER
'l..R.1Le.j.AN POLIS
U4@
WASHINGTON D.C

M
D w-

0. co
4
mr
mom 0
71
0

R
*0
ICH ND
Luul
qD

RGURE 15-2: Physiography of the Bay Area
Appendix 15
11

RESOURCES

The resources of the Bay Region have provided much
toward the development and well being of mankind. The
fish and wildlife, the potable freshwater, the deep-
water arteries and the natural beauty of the Region
are just some of the resources that have contributed
greatly to man's desires to live and work along the
shores of Chesapeake Bay. Unfortunately, man's use
of these resources has sometimes been to the detriment
of the biota that inhabit the Region.

The Chesapeake is one of the most important seafood
harvesting areas in the Nation. Waters of the estuary
yield millions of pounds of finfish and-Shellfish each
year. The fishing industry on the Bay is among the
most colorful in existence and it provides a strong
tie with the past. In addition to the heavy commercial
seafood harvest is an ever-increasing sport fishery,
and countless people go crabbing and clamming for both
food and fun. The marshes of the Bay provide hunting
grounds for waterfowlers and there are numerous species
of upland game. Thousands also enjoy such non-consumptive
fish and wildlife uses as bird watching and photography.

The approximately 8 million people who live in the
Region depend on both surface and groundwater resources
to meet their water supp'ly needs. Approximately 80
percent of the people are served by about 50 major
water systems which provide approximately 900 million
gallons of freshwater daily.

Industry also requires large volumes of water for both
processing and cooling. Daily industrial demands totaled
approximately 1,500 million gallons in 1970. Man's use
and return of the Bay.waters has often created problems
for the biota of the Bay. Reduction in both the quan-
tity and quality of the waters returned cause the most
serious consequences.

In 1970, the navigation arteries of Chesapeake Bay and
tributaries handled nearly 150 million tons of water-
borne commerce worth billions of dollars. The impor-
tance of this activity to the economic structure of
the Regionparticularly the world ports of Baltimore
and Hampton Roads, is inestimable. Recreational ves-
sels also navigate on Bay waters which are considered
to be some of the more pleasurable in America. However,

Appendix 15
. 12

demands for deeper channels f-or commercial activities
and the need for continuing maintenance of the existing
channels creates still another stress on the Bay biota.
The dredging of the channels and the disposal of the
dredge material can have serious impacts on the biota
of the Bay.

Lastly, the very beauty of the Bay with its many
scenic vistas and picturesque embayments has led
man to develop along the shoreline to be near these
pleasures. Unfortunately, in some cases, this shore-
line development has resulted in the destruction of
wetlands and wildlife habitat and the loss of the
very resources that man planned to enjoy.

HISTORY

Since the first exploration and mapping of Chesapeake
Bay in 1608 by Captain John Smith, man has been concerned
with, and indeed,highly_deppndent on, the plant and
animal biota of the Bay Area. Although precious metals
such as gold were hoped for in the "new land", the real
bounty was realized in the abundance and diversity of
these biological resources--deer, waterfowl and upland
game were abundant; profusions of shad, sturgeon, and
drumfish were found; and rich soils for agriculture
appeared inexhaustible. The colonists' interest was
understandably toward the immediate food and/or econ-
omic value of these items; and by 1628, exports of
tobacco to England, for example, reached 1.5 million
po-dnds. Since colonization, agricultural and com-
merical fishing have continued to grow and today are
major factors in the Bay Area economy. The value of
agricultural products grown in the Bay Area was
$589 million in 1969 and the commercial fishery bar-
vest was valued at approximately $41 million in 1970.

The history of knowledge of Bay Area organisms �tems
from the primarily non-technical interest in natural
history of early America. The effort expended on
systemization, and classification of what was found
in nature, gave organization to the accumulated masses
of data. Also, a base was formed for investigation
and debate following release of Darwin's evolutionary
theory in the mid-ninteenth century.

Appendix 15
13

Aside from the observations of natural historians,
resulting in the inventory and classification of many
plant and animal species, economic incentive has
governed the growth of biological knowledge in the
Bay Area. There is little incentive for other than
amateur naturalists to delve into the life history
of an obscure organism of no economic import. Also,
the complexity of study, the long periods of time
needed for life history analysis, and the rapidity
with which environmental changes can occur, preclude
a wholesale closing of the data gap by the scientific
community. As a result, little is known of many Bay
Area organisms, their life cycles, and response to
environmental change. The status of present knowledge
of biota in the Bay Area is treated exhaustively in
the Existing Conditions Report.

DESCRIPTIVE PUBLICATIONS

Despite the many research needs identified by the
scientific community, much information is,available
on the Bay's biota. The single most comprehensive
document completed to date on Bay biota is Appendix C,
Volume II, of the Chesapeake Bay Study.Existing Con-
ditions Report, released in 1973. Prepared by the
Chesapeake Research Consortium, Inc., under contract,
the appendix includes summaries by recognized author-
ities of the various taxa found in the Bay Area,
evaluation of environmental effects criteria, and a
wealth of other information concerning Bay Area biota,
institutions, researchers, and literature sources.

.In 1972, the Virginia Institute of Marine Science
released what is currently the most complete com-
pilation of Bay Area biota: A Checklist of the
Biota of Lower Chesapeake Bay. The list iden7ifies
in excess of 2,650 species, which include certain
recently added plants and vertebrates, but excludes
insects and spiders. Literature for specific taxa
are cited exhaustively.

Earlier works. include a list of plankton by Wolfe,
et al, in 1926; and Hildebrand and Schroeder compiled
their Fishes of Chesapeake Bay in 1928, which is still
considered to be one of the broadest works on Bay biota.
In 1930, Cowles provided a very thorough treatment in

Appendix 15
14

his Biological Survey of the Offshore Waters of Chesapeake
Bay. He listed 250 organisms by at least generic name,
although some groups were treated rather bvoadly. Dr. Willis
Hewatt produced the first checklist of marine invertebrates
at VIMS in 1959, although Dr. Jay Andrews had earlier com-
piled a list formollusks.

PRESENT STATUS SUMMARY

The current best estimate for the total number of Bay
organisms in 2,650, as compiled by Dr. Marvin Wass,
Virginia Institute of Marine Science (VIMS). The
figure includes multitudes of living things from
bacteria, fungi, phytoplankton and microalgae, to the
more familiar fishes, reptiles, birds, and mammals.
Figure 15-3 illustrates the rank of various plant taxa
found in the Chesapeake Bay Area. Spiders and insects
were considered to be beyond the present scope of
study due to the vast number of species involved.
Certain other groups have either been ignored or have
not been known to occur, as yet, bryophytes, rotifers,
gnathostomulids, and kinorhynchs being examples.
Also, deficiencies exist in coverage of the ecologically
underrated protists. Since the VIMS list concentrates
on the lower Bay, some higher plants, birds, and mammals
have not been well covered for Maryland. Fishes,
invertebrates, and algae, however, are considered to be
"reasonably" covered for the entire Bay Area.

To summarize the state-of-knowledge concerning the biota
of Chesapeake Bay, the following comments are provided
essentially verbatim as publithed by Dr. Wass in the
preface to A Checklist of the Biota of Lower Chesapeake
Bay.

"The Chesapeake Bay is the largest of the
hundreds of estuaries found in North America.
It is subjected to broad ranges of temper-
ature, wind, turbulence, and dissolved
oxygen. Salinities range from rather con-
stnat at the mouth to an ecotone, or area
of change-over, with fresh water that may

Appendix 15
15

(D
PLANTS Taxon Rank Number of Species

ul Anthophyta 1 413
Chrysophycophta 2 354
Pyrrophycophyta 3 132
Cyanophycophyta 4 73
Rhodophycophyta 5 54
Chloiophycophyta 5 54
Mycota 6 j6
Phaeophycophyta 7 28
Pterophyta 8 11
0 Euglenophycophyta 9 3
-10 Arthrophyta 10 2
9 Coniferophyta 10 2
7 8 TOTAL 1,162
5
3 4 5

FIGURE 15-3: NUMERICAL RANK OF PREDOMINANT PLANT TAXON

move over a distance of 90 river miles
in a year. Gradient zones, point of great-
est salinity change, occur in each tri-
butary river and the Upper Bay at about
the 10-12 ppt. isohalines. These tend
to delimit the lower boundaries of
nursery grounds, or critical zones.
Turbidity increases up-estuary and a
somewhat controversial flocculation zone
occurs near the head of salinity.

"Organisms range from specialists, largely
biologically controlled by predation and
competition, near the Bay mouth, to gen-
eralists, or fugitive species, which
accommodate to physical factors, in the
upper reaches. Diversity is high in the
lower Bay, often greater in the lower
James and York than near the Bridge-
Tunnel at the mouth, perhaps a result of
greater sediment variations. In the
Chesapeake system, faunistic break points
seem more likely to occur near 10 and 25 ppt.
than at the 'Venice system' levels of
5 and 18 ppt. Seasonal variations in
salinity, with lows typically in April
and highs in October, may be considerable
in the tributary rivers. Superimposed on
these are longer cycles, as in the dry
years of the late 19601s.
1)
"Chesapeake Bay is famous for its pro-
duction of seafood. The great harvests
of croakers in the 1950's is an oft-
recounted memory. The menhaden flue-
tuates in a slow decline while still
making up two-thirds of the total tonnage.
Far behind are alewives and other clupeids
obviously affected now by oceanic fishing
pressure. But all is not gloom; the sum-
mer is 1970 brought banner catches of
spot and trout. Striped bass seem most
successful and once ignored fish receive
increasing catch effort. Eels are air-
freighted live to Holland; catfish trucked
north and west. Difficult to estimate is
the, poundage of all those species of fin-
fish and shellfish taken by sport fishermen
or the value of the bull minnows, clams,
worms, squid, and other invertebrates they
use for bait.

Appendix 15
17

"Blue crabs reach their acme in the Chesa-
peake Bay and catching is most proficient.
Oysters are taken in less volume but are
of great 'value. Oyster culture in lowered
salinities promises a continuing supply
of this gourmet bivalve. Hydraulic
dredging has put Maryland ahead in soft
clams. Long lived but poorly recruited
hard clams sustain a sizable fishery in
the lower Bay. In the face of continued
coastal urbanization, some edible sea-
foods may be of most value for the recre-
ation provided in their catching and
pleasuresome eating.

"Mobile species, such as amphipods, are
able to move with the salinity change;
however, sessile forms may establish
colonies in summer, only to be wiped
out in winter. A very few spedies,
usually abundant ones such as the men-
haden and some amphipods, reproduce
all year. Others such as barnacles,
Mya, and Mulinia exhibit bimodal spawn-
ing behavior; the fall reproduction of
some bivalves often seems more success-
ful than the spring set, presumably
because of blue crab and demersal fish
depredations in late spring. The most
striking vernal phenomena are the spawn-
ing of Polydora ligni and the attendant
mud accretions by newly set worms in
March and April, closely followed by
the mating gyrations of the ubiquitous
Nereis suceinea. The blue mussel, highly
prized by epicures, usually strvives the
summer at the Bay mouth and has occasion-
ally produced large sets at VIMS in winter.
In January and February, 1959, this mussel
became a pest by setting on blue crabs
so heavily that extra hands were hired
to remove them. At this time, W.A. Van
Engel found 196 mussels on a single
female crab.

"The oligo- and low-mesohaline sectors
have become known as 'nursery grounds'
because of the larval and juvenile fishes
transported there from the ocean or fresh
water currents and self-propulsion. In
these murky waters the detritus food-chain

Appendix 15
is

is maximized and young fishes grow large
enpugh to cope with increasing biotic
hazards down-estuary and in the ocean.
Biomass per unit of area, particularly
of marsh plants and fishes, is vastly
greater on these nursery grounds than
it is seaward. Three resident fishes,
the white catfish, white perch and hog-
choker compose over 95% of the fish
volume here. Mysids, amphipods and wedge
clam, Rangia cuneata, predominate in the
biomass of invertebrates. The large
marshes bordering the nursery waters
are rich in angiosperm species, includ-
ing some rare ones, but support only a
few species of birds and fishes, in con-
trast to the Eastern Shore seaside with
its great variety of ichthyo- and avi-
fauna geen against vast cordgrass marshes
and mudflats.

"Sediments typically become coarser toward
the sea. Although deep holes and channels
may bear gravel, deeper areas usually
contain silts and clays. Fresh and olig-
ohaline shallows may support valued
Potamogeton or Vallisneria waterweeds or
be choked by Ceratophyllum, Zannichellia
or Myriophyllum spicatum (Eurasian water-
milfoil). In saltier water, Zostera
marina (eel grass) beds support an amazing
epifauna, abundant infauna, and shelter
for maAy species of juvenile fishes in
summer.

"Communities or organisms are often dom-
inated by a single species in low salin-
ities (e.g., Macoma balthica) while those
in the lower Bay may lack dominants. A
similar event seems to occur from channels
t6)thb outlying shoals, where cirratulids
may predominate in channels -and diverse
psammofauna may exist in the sandy sub-
littoral region. Sand beaches are mo�t
barren, although giant amphipods may
torment the nocturnal stroller. Oyster
'rocks' are species-rich habitats worthy
of more study.

-Appendix 15
.19

"The oligohaline marshes have changed rather
precipitously from being dominated by giant
cordgrass to producing mostly succulent
forbs which often begin dying back in sum-
mer and are laid low by killing frosts.
Wild rice also seems to have been reduced.
The reason for this change is unknown, but
the 10-inch rise of sea level locally in
the last 40 years may have been a con-
tributing factor if sediment aggradation
is inadequate.

"Brackish and freshwater zones exhibit
varying seasonal phenomena including
'red tides', the sensory manifestations
of a few species of opportunistic dino-
flagellates. Silt-laden flood waters
following Hurricane Camille destroyed
thousands of bushels of oysters, but
fattened the survivors. More sinister
are the cyanophycean blooms which
reduce ecosystem stability and complexity
in the upper tidal James and Potomac
rivers, of ten raising the photosynthetic
compensation point to the surface. Low
summer DO's plagued blue crabs in 197i,
after summar rains. Perhaps attracting
most concern among the public is that
bane of bathers, the stinging nettle
Chrysaora, a species possibly benefited
by the increasing practice of culturing
oysters in low salinity areas. Polyps
of this pest occur typically on oyster
shells, although man's litter-also pro-
vides increasing durable surfaces which
serve as substrates.

"Several species seem to have been reduced,
either in numbers of range, in the last
20 years. Examples include the sand dollar
Mellita, the starfish Asterias, the shrimp
0 yrides and most notably, the increasingly
restricted areas in which oysters can be
grown commercially. Most mourned is the
croakers decrease in abundance. Record
of great numbers of sturgeon and some
shorebirds before our time seem legendary.

"Introduced species are more prominent:
Rangia, in all major rivers except the
York, contributes most to the biomass.
Minchinia nelsoni, presumed by some to

Appendix 15
20

be exotic, is the more economically impor-
tant by its impact on oyster culture.
Loxothylacus panopeae from the Gulf of
Mexico markedly reduced Eurypanopeus and
possibly Rhithropanopeus, a doubtful
benefit to oyster culture and decreasing
a food source for diving ducks. Ecteinas-
cidia, if still present, should be welcomed
by teachers because of its see-through test.
Among vertebrates, the cattle egret, glossy
ibis and nutria are highly successful new-
comers, with an ecological impact yet to
be assessed. Eurasian watermilfoil tops
the plant introductions although it has
inexplicably become reduced in speed and
density recently. The Asiatic Aneil6ma
keisak dominates some swamp floors. Russian
thistle does a bit to retard barrier beach
erosion and Carex kobimugi may ultimately
be the best defense of back dunes.

"In general, large animals are better known
than small ones on Chesapeake Bay, espe-
cially if they are eaten by man. Vertebrates
have established common names which are
often widely used and usually more stable
than scientific names; for example, the
striped bass, hard clam, Virginia oyster,
and ribbed mussel are abundant species
which have had their generic names changed
in recent decades. Birds are the most
conspicuous and easily censused vertebrates;
however, among birds and fish a 'curiosity
phenomenon' operates and rare species often
receive more attention than common ones of
greater economic import.

"Biological sampling has been conducted
more intensively near research centers,
in the most accessible sites and,in the
milder seasons. Thus, angiosperms of
wetlands are quite well known near the
coast, poorly so between the York and
Potomac rivers. Some plankters, includ-
ing scyphozoans, ctenophores, the Acartia
copepods, Neomysis, the diatom, SICe-letonema
costatum, and the flagellate, Prorocentrum
micans, have been reasonably studied, but
hundreds of other holoplankters are little
understood. The meroplankton has been
taxonomically studies for most decapod

Appendix 15
21

crustaceans but vast knowledge gaps exist for
polychaetes and other groups. The macrobenthos
is taxonomically knownin general but our
awareness of distribution, life history and
ethology of most species is inadequate. Some
groups, e.g., the organisms from 0.1 - 1.0
mm, have barely been touched in the Bay; for
some communities it is already too late to
study the effects of disturbance."

APpendix 15.
22

CHAPTER III

ECOLOGICAL CONCEPTS AND
ENVIRONMENTAL FACTORS

The Chesapeake Bay provides for the needs of man in
many obvious ways: recreation, navigation, fish and
wildlife, water supply, and wastewater disposal. But,
as apparent as the values are, the true vitality of
all that the Bay represents biologically is keyed to
the sometimes more obscure and even invisible biolog-
ical processes. The food chain begins with the
microbes and bacteria which decompose organic material
into food products and nutrients, and provide certain
links in the natural exchange of gases. These factors,
along with the ecological communities and myriad of
life forms, combine in dazzling intricacy and profu-
sion in the Chesapeake Bay Estuary.

It is toward understanding of these basic biological
concepts that Dr. Forrest E. Payne of the Smithsonian
Institution has authored the balance of this chapter.
The work is an element of the Chesapeake Research
Consortium, Inc., contract referenced earlier and is
a continuation of information presented in the Exist-
ing Conditions Report. All references cited in this
chapter are included at the end of Chapter VI.

Appendix 15
23

ECOLOGICAL CONCEPTS

It is imperative that ecological concepts be understood
by those in position to make water resource management
decisions. It is the managers who have the difficult
duty of deciding, in spite of the limited knowledge
available on dynamic characteristics of an ecosystem,
whether or not to permit certain actions which may
affect environmental parameters. He will have to
contend with repercussions that arise if his decisions
cause deleterious environmental effects. It is,
therefore, necessary that scientists provide managers
with detailed ecological information as soon as it is
available in order to prevent as many harmful environ-
mental effects as possible.

Also, scientific terms should be so defined that a
basic understanding of the topic under discussion
is established. It must be recognized that "the
chief difficulty with ecological terminology is
that many of the terms have conflicting definitions"
(Hedgpeth, 1957). In spite of differences of opinion
as well as of vagueness of definitions, the terms
ecosystem and community are useful, and according to
Hedgpeth (1957), no one would seriously propose to
abandon either term.

ECOSYSTEMS

One of the most widely accepted definitions of an eco-
system is "any area in nature that includes living
organisms and nonliving substances interacting to pro-
duce an exchange of material between living and non-
living parts ... " (Odum, 1959). This interaction is
called the "physiology of ecology" by Hedgpeth (1957).
It is important th recognize that circulation, trans-
formation, and accumulation of energy and matter through
various trophic levels are inherent in the ecosystem
concepts (Evans, 1956; Odum, 1959). Abiotic factors
(the nonliving part of the environment, including both
inorganic and organic compounds) circulate their energy
and matter by such physical processes as evaporation,
precipit.ation, erosion, and deposition (Evans, 1956).

.Appendix 15
24

Producers, consumers, and decomposers (biotic factors)
utilize such means as photosynthesis, decomposition,
herbivory, predation, and parasitism for energy and
.matter transfer and storage (Evans, 1956). A manager
must understand this transfer of energy matter from
one level to another. He also must recognize the
regulatory mechanisms which limit abundance and influ-
ence their metabolic activities; some of the more
important regulatory mechanisms are ones that affect
growth, reproduction, death and behavioral patterns,
e.g., migration. A disturbance of even one of these
regulatory mechanisms may cause the ecosystem to cease
to exist in its present identity (Evans, 1956).

COMMUNITIES

.The biotic portion of an ecosystem consists of organisms
which form communities. The community concept must
therefore be explored in order'to understand the eco-
logical impact of a community on the ecosystem in which
it exists and vice versa. It is not the intention of
this report to present the various ways of defining a
community* nor to delineate a community from a popula-
tion or assemblage, but rather to present a generalized
concept of the interrelationships of organisms for
managers to use in their work.

Odum (1959) defined a biotic community as "any assem-
blage of populations living in a prescribed area of
physical habitat; it,is a loosely organized unit to the
extent that it has characteristics additional to its
individual and population components." He point out that
a biotic community can be-further subdivided into major
and minor communities. A major community is able to exist
independently of all other communities because it has all
the necessary components (abiotic substgnces, producers,
consumers, and decomposers) for maintaining itself, except
for energy,from the sun. If the assumption by Reid (1961)
that an estuary is a mg-ijor community is accepted, then the
organisms associated with one another within an estuary
comprise minor communities. These minor communities are
dependent upon neighboring organisms to a greater or lesser
extent.

The term biocoenosis should be called to the attention of
managers. Karl Mobius (1877) first used this term when he
expounded on his concept of an ecological community. His
concept is still used by Europeans, basically in the same
context as our use of the-word community. It emphasizes
relationships between organisms and between them and the
physico-chemical parameters in their environment. Append .ix 15
25,

Both biological composition and organization are
included in the community concept,(Reid, 1961). Community
composition is the aggregation of organisms typically
associated with one another. Evolutionary diversification,
specialization and adaptation to various environmental
conditions has resulted in distinct aggregations. A rec-
ognizable unity therefore prevails among certain organisms.
A pattern, or organization, of these aggregations exists,
determined by the flow of matter and energy (metabolism)
throughout the community (Odum and Copeland, 1974).

Managers should realize that community composition is
paralleled in different geographical areas. Species sub-
stitution occurring in parallels of the "Macomall community
in the Arctic, the boreal, and the Northeast Pacific is
illustrated in Figure OW-4. Kxamples o@ niche substitution

io 00

The em.
To. k.m... a.
rr""44'efts two"
CardWe

me.
phte" bons"
- @7_

+414

wooer%
fte I
I

Tb, Th,
0.14 q-@ b-Itics M
PUNW1141113A. .8-0 pon.4

FIGURE 15-4: PARALLELISM BETWEEN'THE ARCTIC, BOREAL,
AND NORTHEAST PACIFIC MACOMA COM MUN ITIES
(Thorson, 1957)

Appendix 15
26

by various invertebrates living in the different physico-
chemical estuarine conditions of the Chesapeake Bay, of San
Francisco Bay and in European estuaries are.given in Table 15-1.
Basically, the types of communities found in particular
geographical regions depend upon the energy relationships
ofthe environment, species characteristics and species
functions (Reid, 1961).

According to Odum (1959), "Community names like names
for anything should be meaningful but kept as short as
possible. Otherwise, the name will not be used". He
classified communities in three ways: by their major
structural features, by the physical habitat in which they
live and/or by their functional attributes, such as com-
munity metabolism. The first two means of classification
are presently the most commonly used. A major structural
feature often used to designate a community is a dominant
species or an ecological dominant., i.e., the organism(s)
controlling the energy flow or producing the greatest pro-
ductivity. Classification of a community by its physical
habitat is essentially self explanatory. Two physical
characters by which a bay community can be classified are
salinity gradients and seasonal temperature variations.
Acting individually or together, both of these factors
can restrict both transient and resident community organisms
to particular spatial and temporal distributional patterns
(Swartz,, 1972).

The least used means of community classification, by
a functional attribute, is probably the best for comparison
of all communities (terrestrial., freshwater,, estuarine and
marine). This method was utilized by Odum and Copeland
(1974) in.classifying coastal systems. It involves
community metabolism determination including the fixation.
utilization, and transfer of energy through the trophic
levels from primary producers through the carnivores.
Any alteration of a trophic level results in a shift in
community metabolism which causes a change in community
structure. An example of community structure alteration
caused by the modification of food chain relationships
is illustrated in Figure 15-5.1

An ultimate goal of water resource managers of the
Chesapeake Bay should be the prevention of major alter-
ations of community structure. All human activities have.
some impact on the environment. Managers of the Chesapeake
Bay should recognize that the disappearance of organisms about

Appendix 15
27

> TABLE 15-1
id
@d TAXONOMIC PARALLELS BETWEEN SPECIES OF CHESAPEAKE BAY,
(D EUROPEAN ESTUARIES, AND SAN FRANCISCO BAY (Boesch, 1971)
OD 0@

CHESAPEAKE BAY EUROPE SAN FRANCISCO BAY

Nanertean A Prostanatella obscura ?

Peloscolex heterochaetus Peloscolex heterochaetus 'Oligoehaetal
Ollgochaete C (Peloscolex) P. ben@-deni

Hypaniola grayi Hypania invalida

Scolecolepides viridis

Hydrobiae Wdrobia ulvae canplex

Macam balthica Macoma balthica Maccma inconspicua
Macama mitchelli

Leucon americanus

Cyathura polita Cyathura carinata

Chiridotea alrqm Mesidotea entomon Synidotea laticauda

Gamnarus daiberi Ganrwus duebeni
G. tigrinus G. zaddachi
G. palustris G. salinus

Leptocheirus plumosus Leptocheirus pilosus

Melita nitida Melita plamata

Corophium n. sp. Corophium volurator Corophium spinicorne
C. lacustre C. lacustre C. stiMsoni

4le; 2 3

4 5 6

7 9 10

ECOSYSTEM

Nurnb*rs 1-10 =organisms RESULT
30 anorgy flow(E)

2 3

0 8 9 10
-DISTURBED ECOSYSTEM

FIGURE 15-5: SCHEMATIC DIAGRAM OF THE EFFECTS OF STRESS ON
ENERGY FLOW IN A SIMPLE ECOSYSTEM (Modified
from McErlean and Kerby, 1972). Appendix 15
29

which little is known or a change in the abundance of
particular organisms can be critical enough to jeopardize
the stability of an estuarine community (Swartz, 1972).

LIMITING FACTORS

The survival of an organism and the stability of the
estuarine.community in which it lives are both influenced,
positively and negatively, by the environmental factors
with which they interact. These environmental factor s
are collectively called "limiting factors" by ecologists.
The concept of limiting factors is based on two basic
principles. Liebig's "law" of the minimum, as stated by.
Odum (1959), is "the essential material (necessary for
growth and reproduction) available in amounts most closely
approaching the critical minimum needed will tend,to be
the limiting one". Shelford's "law" of tolerance, on the
other hand, states basically that the well-being of an
organism is controlled by the qualitative or quantitative
deficiency or excess of any one of several factors that
approaches the tolerance limit of an organism (Odum, 1959).
In other words, ecological minima and maxima affect biotic
behavior and even survival. Odum (1959) pointed out that,
although the physical requirements of an organism are
fulfilled, the failure of biological interrelations may
still cause death. Subsidiary principles to these laws
as listed by Odum (1959) are:

1. "Organisms may have a wide range of toler-
ance for one factor and a narrow range for another."

2. "Organisms with wide ranges of tolerance
for all factors are likely to be most widely dis-
tributed." ,

3. "When conditions are not optimum for a
species with respect to one ecological factor, the
limits of tolerance may be reduced with respect to
other ecological factors."

4. "The limits of tolerance and the optimum
range for a physical factor often vary geographically
(and also seasonally) within the same species."

5. "Sometimes it is discovered that organisms
in nature are not actually living at the optimum
range (as determined experimentally) with regard

Appendix 15
30

to a particular physical factor. In such cases
some other factor or factors are found to have
greater importance."

6. "The limits of tolerance for reproductive
individuals, seeds, eggs., embryos, seedlings, larvae,
etc., are usually narrower than for non-reproducing
adult plants or@anirhals..

The two laws, Liebig's "law" of the minimum and
Shelford's "law" of tolerance together with the subsidiary
or principles constitute the concept of limiting factors.
An example of limiting factors is graphically
illustrated in Figure-3. Three physical factors are acting
on a hypothetical burrowing animal: salinity, substrate
and tides. The requirements for survival are (1) salinity
not much lower than sea water, (2) a sandy substate and
(3) a limited amount of exposure such as that occurring
between mid and low tide. A study of Figure 15-6 shows that
in the available area" a minimum of two factors limits
the animal to the area described.

HIGH WATER

MID TIDE
17/f, ILI I/ I
AREA COLONISE
cc
4!

LOW WATER

SALINITY UNSUITABLE SALINITY SUITABLE

BED Of ESTUARY
FIGURE 15-6: DIAGRAM TO ILLUSTRATE LIMITING
FACTORS IN TRE BED OF AN ESTUARY
(Day, 1951)

Management should be aware of how the limiting factor
concept (as based on Liebig's "law" of the minimum, Shelford's
"law" 6f tolerance and the subsidary principles) can affect
the structure and survival of Chesapeake Bay communities.

ADDendix 15
31

ENVIRONMENTAL FACTCRS

The major concern of this section of the report is to
discuss the environmental parameters (biological, chemical
and physical) that affect the biota of the Chesapeake Bay.
It is these parameters which act.as "limiting factors".
Estuarine managers must appreciate the interactions of these
parameters in order to make knowledgeable decisions.

The Chesapeake Bay is considered an estuary which is
defined by Pritchard (1967) as "a semi-enclosed coastal body
of water which has a free conriection with the open sea and
within which sea water is measurably diluted by fresh water
from land drainage". In other words, it is an unique system,,
being neither a fresh water nor a marine ecosystem.

Pritchard (1955, 1967) classified estuaries into four
types: A, B, C and D. Chesapeake Bay fits his classification
of a Type B estuary; i.e., circulation is aided by tidal
mixing of two water layers, causing an increase in the net
volume of water flow. The two water layers consist of an
upper, lower salinity, seaward flowing layer and a bottom,
higher salinity layer flowing toward the head of the estuary.
Thus, the Chesapeake Bay is considered a moderately stra-
tified estuary (Bumpus, Lynde and Shaw, 1973).

The geographical shape of an estuary is important
because it directly affects the actions of the physical factors
within the bay. Figure,15-7 is Day's plan of an ideal estuary.

HEAD :UPPER REACHESWIDDLE REACHES
:MOU

PARAMETER
Salinity SplOt-5-15PPIt- 15 2Sppt - - 25ppt
Substrate Mud - sandy mud - - -Sand or Rack
Current SlOW - - - - - -Fairly Fast - - -Rapid

FIGURE 15-7: PLAN OF AN IDEAL ESTUARy
TH

LV
W

Modified from Day (1951)

Appendix 15
32

The original shape and depth of the Chesapeake basin has
been modified by sedimentation brought down by the rivers,
by tides as they range up the Bay, and by wave action.
These physical factors, individually and in combined action,
affect the fauna and flora and, therefore, the communities.
For example, the shape of the mouth partially determines
the distribution of seawater which entered the Bay with the
tide. The distribution of the biota thus depends upon their
salinity tolerance. The depth of a bay mouth may also
affect the constitution of bay biota since it partially
restricts the ability of organisms to enter and leave the
mouth (Day, 1951). According to Boesch (personal commu-
nication) depth of the Chesapeake Bay mouth is not known
to prevent faunal movement.

PHYSICO-CHEMICAL FACTORS

Consideration is made in this section of the effects of
physical and chemical variables 6n the Bay's biota.

SEDIMENTATION

Estuarine sediments are unique; they are of marine,and
terrigenous affinities and yet retain their own integrity
(Nelson, 1962). Inorganic sediments originate from a
variety of sources, including the rivers, bordering sea
cliffs, adjacent sea floor, and reworking of the marshes
(Emery and Stevenson, 1957b). Organic sediments are con-
tributed by rivers, the estuary itself, and/or the ocean.
Emery and Stevenson (1957b) considered organic sediment
a "burial assemblage" since it is comprised of dead plank-
ton, pieces of plants, decayed organisms, etc. Organic
sediments are also formed by fecal and pseudofecal pellets
excreted by benthic organisms (Moore, 1955) and by sedi-
mentary particles cast off by burrowing animals in their
search for shelter and food (Carriker, 1967).

The bulk of the sediments domes from the rivers. When
freshwater with its suspended sediments enters an estuary,
it flows on top of the more saline water because 6ffthe
lighter density of the former. Generally, coarsest par-
ticles are deposited before finer particles (Carriker,
1967). The silt, making up the majority of the suspended
material, is deposited as soft mud in low salinity zones
(Emery and Stevenson, 1957a). If deposition is slowla
deposition rate may smother the inhabitants (Day, 19 ).
The clay portion of the suspended sediment differs from
silt in that it possesses a charge and attracts other
particles, resulting in flocculation (Emery and Stevenson,
1957b).

Appendik 15
. 33

Bader (1962) demonstrated the absorption of dissolved
organic materials by clay minerals to form clay-organic
complexes. The composition of these complexes is controlled
primarily by the "crystallographic structure of the mineral.,
its molecular weight, functional group, and structure and
the molecular weight, functional group, and structure of
the organic compound" (Carriker, 1967). These macroscopical
organic-inorganic complexes are often called detritus.
Detritus, an important food source for many estuarine
organisms, occurs in suspension as a loosely aggregrated,
flaky mixture of organic molecules, includ@ng "vitamins,,
organic colloids and organic fragments intermixed with
various proportions of clay, silt, fine sand and living
microbiotall (Carriker, 1967). Since the specific gravity
of these organic-inorganic complexes is near that of
estuarine water., they can be held in suspension a long
time, but eventually this flocculated material falls to
the deeper floors of an estuary.

Sedimentation results from the "reworking" of shallow
tidal beds and tidal channels. Waves and currents keep a
bay in a state of dynamic flux. One of the best examples
of "reworking" was done by Hunter (1912) in the Chesapeake
near the mouth of the Choptank River. He compared maps
made in 1848, 1900 and 1910 and found that erosion on low-
cliffed shores of clay and marsh amounted to as much ad
110 ft/yr. Three islands were removed by this erosion
and at 30-ft depths the bottom was deepened or shoaled
by as much as 6 ft (Emery and Stevenson, 1957b).

The sedimentation rate in the Chesapeake is determined
by the force of gravity, the vertical turbulence created by
the water., and by the supply of sediments (Carriker, 1967).
Deposition of materials is greater at ebb tide, when current
velocities are slow and flow duration is greater, and also
during neap tides when lower tidal amplitudes and corre-
spondingly lower current velocities are present.

Macrophytes can change the sedimentation rate by serv-
ing as traps to prevent sediment movement. Wilson (1949)
described the changes in sedimentation rate in the Plymouth
District, U.K., caused by the loss of eelgrass (Zostera).
Before its loss, the eelgrass had trapped suspended materials
to such an extent that a channel had to be dredged peri-
odically to allow boat passage. Apparently, this dredging
was no longer necessary after the eelgrass loss since the
sediments were not retained, but quickly washed on out to

ADpendix 15
34

sea. Dexter (1944) described changes in the benthic
organisms comprising the eelgrass community at Cape
Ann when loss of the plant allowed the sediments to
spread unchecked.

SUBSTRATLE

Estuarine substrata are formed by sedimentation.
Emery and Stevenson (1957b) considered estuaries as areas
with low topographic gradients, active sedimentation and
bottoms composed of muds and sand in various combinations.
In general, mud is found at the head of an estuary, whereas
abundance of sand increases near its mouth. In the Chesapeake
Bay, fine silts are found in the deeper waters whereas finer
sediments are found in the channels except where scouring
action is heavy. The eastern shore of the Bay is sandier
than the western because of the greater river inflow into
the western portion of the Bay (Boesch and Wass, personal
communication).

Carriker (1967) considered the best known substrate
areas as those regions in the upper reaches and quiet
lateral areas of an estuary. These substrates consist
of clays, silts and organic materials. The areas of the
inlets, the wave exposed shallows, the intertidal zones and
the bottom areas consist of admixtures of sands and coarser
particles because of the presence of wave action and/or
strong currents (Day, 1951). Hard surfaces such as rocky
substrates, oyster reefs and shell deposits nearly always
are covered by some form of sedimentation except where
strong water action keeps them clean (Percival, 1929; Day,
19,51). The flat portions of the floors of estuaries deeper
than three fathoms are often covered by a sediment blanket.
The particles forming this blanket become increasingly finer
as depth increases. This ideal distribution of sediments
is possible in Chesapeake Bay only because of the rela-
tively flat bottom and the mild wave and current conditions
(Emery and Stevenson, 1957a).

Substrate has long been regarded as a limiting factor,
but little research has been accomplished on the association
of the distribution of organisms with the bottom type.
Brett (1963), McNulty,, Work., and Moore (1962). Sanders
(1956 1958, 1960) and Sanders, Goudsmit, Mills and Hampton
(19621 are among the few researchers performing detailed
investigations of this association. A summary of some
of their results follows since it will be useful for

Appendix 15
35

comparison with studies of community structure in the
Chesapeake Bay.

In Sanders' (1956, 1958) studies he demonstrated
quantitatively that., for both Buzzards Bay and Long Island
Sound, deposit feeders dominate the mud whereas filter
feeders dominate the sandy sediments. On the basis of
these findings, Sanders suggested that the quantity of
clay in a particular system be used as a method for
determining the distribution of deposit feeders. These-
organisms utilize the complexes formed by clay and organic
material as a primary food source (Grim, 1953; Bader, 1962).
Detritus, as these clay-organic complexes are called, tends
to accumulate on muddy sediments. If its concentration is
increased, it will cause a reduction in the oxygen content
of the water, creating anaerobic conditions. Those
organisms which cannot function as.a result of this
reduction will di*e. For example, a greater than 3% con-
centration of organic material causes a decline in the
population density of infaunal bivalves (Bader, 1954).
Sanders (1958) concluded that hydrodynamic processes
control the distribution of filter feeders in fine sandy
sediments. The densest concentration of organisms was
found in a weak., steady current, which provided a
stable environment and a constant food supply. Sanders
(1960) showed that there was a continuum of benthic species
associated with gradual changes in sediment composition.

In contrast to the above studies., intertidal deposit
feeders were found as dominant organisms in both mud and sand
in Barnstable Harbor., Massachusetts (Sanders, et al., 1962).
Since the substrate in these habitats is stable, dense concen-
trations of diatoms and dinoflagellates are present and
utilized as a food source. Sanders concluded that sediment
should be used as the indicator of the food source and not
the factor determining the distribution of feeding types.

McNulty, et al. (1962) demonstrated that in Biscayne
Bay, Florida, detrital feeders were more abundant in the
fine sediments whereas deposit and filter feeders were
more abundant in the intermediate grades. The results
of this investigation indicated that as particle size
increased., so did the body size of deposit feeders (not
detrital or filter feeders) except in the coarse sediments,
which did not support any type of large population.
Brett (1963) working in Bogue Sound, North Carolina,

App endix 15
36

found that feeding habits of animals are related to the
hydrodynamic characteristics of the environment. Basically,
he found detrital feeders in the areas of slow currents with
sediments having a 0.09 mm mean diameter, whereas the
largest populations of filter-feeders were in the area
where the mean grain size exceeded 0.09 mm (0.12-0.14 mm).

It must be emphasized that the same research meth-
odology was not used in the studies described above, but
generalizations of the research results can still be made.
A close relationship between the faunal feeding habits, the
amount of organic content and the physical nature of sedi-
ments appears to exist. All three studies indicated the
importance of movement of the overlying waters and the
important role of sediment as a food source for benthic
organisms. The questions that can arise from the results
of these studies are numerous and point out the definite
need for a great deal more study. The above generalizations
were based mostly on macrobenthos (large organisms). The
relationships of meiofauna (small organisms) and the substrate
are even less well known.

The interrelationships of limiting factors are further
demonstrated by the tendency of the muddy bottom of estuaries
to retain a higher salinity than the overlying water even
though-the tide Is receding. The marine infauna are there-
fore allowed to penetrate farther up an estuary than the
marine epifauna which are restricted by their tolerance of
the salinity fo the overlying water (Figure 15-8). According

WATER SALINITY IC 11-3
..........

MUD - - - - -- -
10- ?
DISTANCE FROM ESTUARY MOUTH IN MILES

FIGURE 15-6: DISTRIBUTION OF SALINITY AT LOW WATER IN THE
M_TDDY FORESHORE OF AN ESTUARY
(Emery and Stevenson, 1957a)

to Boesch (personal communication) this factor is important
for "fluctuating" estual-ies, nbt generally for the Chesapeake,
Bay which is a gradient estuary.

Appendix 15
37

Nelson (1962) pointed out that estuarine sediments
and substrata are important in maintaining the chemical
conditions necessary for the survival of the benthos.
In order to fully appreciate an estuarine ecosystem.,
managers must realize that "the chemical complex consists
of the interdependent factors of texture and structure,
organic content, pure water chemistry, ion exchange
equilibrium, gas equilibrium and microbiological activity"
(Carriker, 1967). The structure and texture of sediment
in aitu establishes the framework within which chemical
and biotic processes operate.

WAVE ACTION

The effects of waves on'sediments and substrata has
already been mentioned but will be described here in more
detail. The decrease in wave action is probably one of
the most obvious differences between an estuary and the
open sea (Day, 1951). This decrease is caused partially
by the shorter distance for waves to-traverse in an
estuary as compared to the ocean, its relatively shallow
bottom (Emery and Stevenson, 1957a) and the 'shape of the
mouth (Day, 1951). Moore (1958) stated that-waves are
ecologically important to the intertidal zone of an estuary
although they are felt to a reduced extent on the bottom
in deeper waters. Furthermore, they do not affect light
penetration in estuaries as much as they do in the ocean,
but they do influence aeration and mixing to a moderate
depth.

Day (1951) demonstrated that wave action affects
estuarine fauna and flora. The geographic makeup of a
South African estuary made it possible for him to separate
the effects of wave action from the effects of salinity
and temperature on the biota. By observation of the fauna
and flora of this estuary,,...an'd of a nearby shore with
moderate wave action, Day demonstrated that they had few
.organisms in common. It is doubtful, however, that waves
have as much influence on the biota of the Chesapeake Bay,
as they do in the South African estuary, except possibly
at the Bay mouth.
In the Chesapeake, the wave action which wets the
upper zones of the shore with spray is beneficial to some
species. In sheltered waters the mixing of water by wave
action is extremely impoi@tant for the prevention of
excessively high temperatures and salinity stratification.

Appendix 15
38

Ecologically, minimum wave action may be important in an
estuary in maintaining wet conditions in the intertidal
zone, in providing sufficient oxygen for respiration, and
in keeping detrital particles in suspension as a food
source.

TIDES, CURRENTS, AND CIRCULATION

Waves and currents both move water particles, but
their effects on an estuarine ecosystem vary considerably.
Waves directly affect light penetration to some degree
whereas currents do not. Currents however do carry suspended
sediments which reduce transparency and hence inhibit light
penetration. Currents do not form splash zones nor do they
cause damage to organisms by impact, but in conjunction
with particles suspended in the water, they can harm delicate
organisms by their abrasive activity. Currents are relatively
stable except when affected by the tidal cycle. If a current
is strong and causes substrate shifting, impoverishment of
fauna and flora occurs in that area (Moore, 1958). On the
other hand, if a current does not cause the'substrata to
shift, the biota may be rich in both abundance and in
number of species.

The effects of tides on organisms need to be considered
only in relation to exposure and immersion. The duration of
exposure and immersion controls the severity of such adverse
factors as desiccation, insolation and exposure to high or
low air temperatures as well as of the availability of time
for feeding and for larval release (Moore, 1958).

Both currents and the tidal cycle are biologically
significant in other ways. They provide mixing, transpor-
tation and deposition of inorganic and organic nutrients.
"Net circulation" aids in the retention of pelagic larvae
for repopulation of existing estuarine communities (Carriker,
1967). Other biological aspects affected by water movement
are in "mingling and dispersing gametes, spores, larvae
and minute older stages; in removal of metabolic products
from and bringing food and oxygento fixed benthos; and in
flushing from the sediment metabolic products.of benthic
microbiological activity" (Carriker, 1967). Currents are
often overlooked aids to distribution. They circulate
chemical "clues" which help predators locate their prey,
distribute benthic organisms that have floated off the
substratum and invertebrates which crawl under the surface
f@lm, and guide current-oriented organisms (Nelson, 1928;
Carriker, 1957).

Appendix 15
39

Without circulation,, as at the bottom of deep estuaries,
stagnation can cause a "desert" area. Depth as a limiting
factor in the provision of oxygen and food to the bottom of
an estuary should be considered only when circulation is
absent and insofar as it affects salinity and temperature.

SALINITY

Salinity is affected by tidal circulation. In the
Chesapeake Bay, salinity increases from near 0 pptat the
head to near that of sea water (approximateiY 30 ppt) at
the Virginia Capes (Bumpus, et al., 1973). An overview
of the Bay shows an oblique distribution of salinity
isohalines, i.e., a higher salinity is found on the eastern
shore than on a comparable area on the western shore.
Figure 15-9 s-hows typical isohalinOs- of the Chesapeake Bay
as drawn by Prichard (1952).

I nw
nt

W-W

"LIZ, an-

FIGURE 15-9: TYPICAL SURFACE SALINITIES IN
CHESAPEAKE BAY (Pritchard,.1952)

-k

Appendix 15
40

The obliqueness of the isohalines is caused by the greater
river inflow on the western shore and by the earth's
rotation. The river inflow is also responsible for the
lateral slope of the salinity wedge that can be observed
by facing the mouth; the right side is deeper than the
left.

Estuarine waters are essentially brackish* with
variable salt concentrations and dissolved salt compositions
similar to that of sea water (Day, 1951). Estuaries are
therefore more saline than freshwater but less saline than
marine. It is important to distinguish the difference
between fresh and estuarine water. Pritchard (1967) indicated
that in the Chesapeake Bay the "estuary proper extends up the
drowned river valley only so far as there is a measurable
amount of sea salt". Some dissolved solids (i.e., salts)
are present in freshwater, but since salts derived from land
differ from those of sea water, the upper limit of the estuary
is sharply delineated by the difference in the major con-
stituents of river and sea water. Prichard (1967) utilized
the ratio of the chloride ion to total dissolved solids of
sea water which is about 1:1.8 for sea water compared to
a ratio of 1:10 to 1:20 for freshwater.

It is generally known that estuarine waters contain
fewer species than either fresh or marine waters, but it
is interesting to note that the placement of the lowest
number of species is closer to freshwater than to marine
water. The reactions of animals to salinity dilution or
increase varies. Remane and Schleiper (1971) described
certain generalized reactions of ecological significance:
that "on reduction of salinity the marine macrofauna
decreases more rapidly than the microfauna", that "reduc-
tions of species in groups forming a calcareous skeleton is
greater than in their relations lacking such a skeleton", that
11groups which have invaded the saline areas from freshwater

According-to Hedgpeth (1957), the term brackish includes
a connotation of relatively'stable conditions whereas the
term estuarine re@fers to the waters that are subject to
tidal and seasonal variations. Many investigators disagree
with this meaning; however, as yet they have not published
their definitions.

Appendix 15
41

and have developed distinct species in brackish waters
and in the sea, display the usual reduction of species
where the brackish region starts; but there is no minimum
of species in brackish water or else it is only slightly
indicated", and that in "some groups there is a complete
gap in the mesohalinikum; that is they exist in high and
in low salinities, but not in intermediate ones". It is
still an open question as to why a reduction and poverty
of species occurs, but undoubtedly a partial explanation
is that any change in an ecological factor (e.g., salinity)
disrupts the stability of an ecosystem, which in turn
limits the inhabiting organisms to ones tolerant of chang-
ing environmental conditions. Figure 15,10 illustrates the
distribution of species in relation to salinity.

FRESHWATER ESTUARY MARINE
0 0 4)0 4) 0
0 0 6 0 4) 0 00 0 -0 00 0
0 4) 0 0 0 V 0 0 0 0
04) 4)000 old) 0 0 00 0
0 0 0 0,() '1) C) 4) 0 0 00
0 04) 04DOOO 00 00
4) 0,() )S oq)c) 00 000000
no Coo )O@00 0
a 000 004 4) 00 000
0 CC) 04)000 000no
0 0 00 0 0 0 0 0 00- 0 0
.0. 00 0 0 0 0 00 000 0
Cr 5 10 15 20 25 30 35
SALINITY (ppt)
e Freshwater 4DEstuarine 0 Marine
Organisms Organisms Organisms

FIGURE 15-10: A GENERALIZED CONCEPT OF NUMBERS
OF SPECIES IN RELATION TO RALIVTTV

Water movement in a bay constantly changes salinity
levels-. Inhabiting organisms therefore must have efficient
osmoregulatory mechanisms. Euryhaline organisms, which
tolerate a wide range of salinity, constitute the majority
of total estuarine taxa (Day, 1951; Carriker, 1967). Some
stenohaline organisms which tolerate salinity change only to Akl
a limited extent are also present. The osmoregulatory ability
of individual species will not be described here; this ability

Appendix 15
42

-is mentioned to point out that salinity changes cause
stress situations which can upset community homeostasis,
i.e., equilibrium between organisms and their environment.

Some organisms are able to adjust to gradual shifts
up and down the salinity gradient although sudden changes
may cause irrevocable damage. Managers must consider this
possibility when they are faced with a situation that can
cause a sudden shift in the salinity gradient. The effects
of ionic fluctuations (salinity) on the behavior and dis-
tribution of estuarine benthos and on community structure
have not been reported in any detail (Carriker, 1967).

LIGHT AND TURBIDITY

Suspended material, more than any other physical factor,
determines the distance light will penetrate in an estuary'
*(Day, 1951). The quantity of light that reaches the bottom
is highly variable because of its dependence upon the d.is-
charge of muddy streams and rivers, variations in plankton
blooms and changes in solar radiation striking the estuary
(Carriker, 1967). This variability is often-related to
seasonal changes. In 1938 Cooper and Milne stated: "In
water, therefore, the region of optimum transmission will
result from two opposing factors - absorption by suspended
matter cutting out the blue and green, and absorption by
the molecules of water and the dissolved salts cutting
out infrared and much of the visible red".

It is extremely difficult to individually consider
the factors of light penetration and turbidity in an
estuary. Turbidity, caused by the river water discharges.,
reduces the amount of light penetration. Wave action,
current,and tides all aid in the transportation of this
suspended material throughout an estuary, thus maintain-
ing the turbid conditions. Since estuarine waters are more
turbid than marine waters, their bottoms consequently
receive less light than the sea bottoms (Day, 1951;.Carriker,
1967). This absence of light may be beneficial to photo-
negative benthic organisms since they can come out during
daylight hours and feed. In contrast, turbid conditions
are hazardous for light-sens@itive organisms that use shadows
cast by predators as a warning to withdraw into areas of
safety.

It has been suggested by several investigators (Nelson,
1916 and 1926; Thorson, 1957, Carriker, 1961; Haskins., 1964)

Appendix 15.
'43

that light plays an important ro 'le in the behavior and
distribution of the pelagic larvae of benthic organisms,
depending on their degree of light sensitivity (Carriker,
1967). Little information is available on the specific
effects of light on organisms and the portion of the
spectrum effectively useful to these organisms. Haskin
(1964) discovered that oyster larvae respond to salinity
changes only under light with a maximum transmission of
575 u and passage through a yellow-grain filter.

Light is necessary for photosynthesis. However, the
harmful effects of light, especially in the violet and
ultraviolet parts of the spectrum, must be recognized
(Moore, 1958). They include the rapid breakdown of certain
vitamins and the restriction of plankton during the daytime
to a depth considerably below the water surfacL- (Moore,
1958). Some of the planktonic crustaceans are restricted
by a diurnal vertical behavioral pattern, i.e., the migration
of organisms to the surface at night and to deeper depths
at midday. This phenomenon is influenced both by illumina-
tion and by temperature, but it is still not completely under-
stood (Moore, 1958; Reid, 1961).

Turbidity limits the depth at which photosynthesis can
occur (Day, 1951). If turbidity is great, then the distri-
bution of plant life is limited because of the restriction
of photosynthetic activity. This restriction of plant life
(especially plankton in the open estuary), will reduce the
benthic and zooplankton populations which in turn will.
reduce the amount of fish productivity.

Natural turbidities should be determined for the
Chesapeake Bay in order to predict the potential annual
productivity of the Bay. Managers should not allow any
effluent to enter the Bay which affects the aquatic biota
in a detrimental manner br,the changes it causes in turburdity
and/or color.

OXYGEN

In the presence of light and carbon dioxide, plants
produce oxygen, and animals take in oxygen and give off
carbon dioxide as they respire. At night, both plants
and animals give off carbon dioxide in their respiratory
activities; therefore, the oxygen concentration of an
estuary is at its minimum at night and at its maximum
during the day. The reverse situation is true for carbon

App endix 15
44

dioxide. The oxygen content of an arm of the Chesapeake
Bay showed 85% oxygen saturation before daylight and 115%
saturation in the late afternoon (Newcombe, Horne and
Shepard, 1939).

Another source of oxygen in addition to its production
as a byproduct of photosynthesis is the atmosphere. Oxygen.
diffuses across the water-air interface. It then is tran-
ported throughout an estuary by turbulence, sometimes
caused by wind, and convection currents (Day, 1951).
Benthic and planktonic organisms are responsible for the
removal of some oxygen from the water. Another source
of oxygen removal is the bacterial decomposition of large
quantities of organic matter present in suspension and/or
on the bottom of estuaries (Day', 1951). This decomposition
of organic matter can cause anaerobic conditions which can
result in death for many aquatic inhabitants.

Oxygen appears to be a limiting factor in respiratory
activities of estuarine organisms when it reaches a low
of 1.0 to 2.0 ml/liter although some organisms survive at
concentrations as low as 0.1 ml/liter (Emery and Stevenson,
1957a). The distribution of dissolved oxygen at a depth
of 10 ft in the Chesapeake-Bay is illustrated in Figure 15-11.
(Kester and Courant, 1973). Newcombe., et al.(1939) found
that the deeper waters of the Chesapeake contain 2 ml/liter
during the summer months when the stratification of the
water inhibits turbulent mixing of oxygen to the bottom
(Emery and Stevenson, 1957a). This figure is not accurate
for the summer of 1973, especially in the upper estuary
close to Baltimore, for two reasons: an extremely long
heat spell and chemical dumping. "In industrial areas
the situation can be further aggravated by the dumping
of chemically reduced wastes that take up oxygen from
the bottom water during their oxidation", (Olson, Brust
and Tressler, 1941; Tully, 1949). The phenomenon of low
dissolved oxygen is typical in the Severn, Potomac, and
Eastern Bay in the summer. In the main portion of the
Bay, anoxic donditions* have not yet been observed (Kester
and Courant, 1973).

Kester and Courant (1973) defined anoxia conditions as
flundetectable oxygen concentrations and the presence of
sulfide".

A-ppen dix 15
45

77* 76*

CHESAPEAKE BAY

d'
10 ft. DIOASOLVED 0(ml/l') ^1
2

39* 390

$61

3W- 38'

'8
1-h

@7 -374

77* 76'

FIGURE 15-11: DISTRIBUTION OF DISSOLVED OXYGEN AT A
DEPTH OF TEN FEET (Kester and Courant,
1973)

Anpendix 15
46

Oxygen concentration varies inversely to water tem-
perature. This knowledge has caused much of the concern
regarding the discharge of heated effluent from power
plants. This heat, if 'not strictly controlled, can
cause deleterious effects on communities. Nature herself
creates unfavorable environmental conditions., such as high
temperatures. The heat spell at the end of August, 1973,
in the Potomac and Rappahannock Rivers resulted in low
oxygen concentrations in their bottom waters, causing
oyster kills at a depth below 17 ft (Wass, personal
communication). Sewage pollution also causes the reduction
of oxygen concentration in the water. Some organisms are
able to tolerate low,oxygen concentrations. For example,
Mya arenaria can survive an absence of oxygen for a period
of eight days. As a result, however, it suffers a decrease
in glycogen content and a poor growth rate (Ricketts and
Calvin, 1948; Moore, 1958).

Managers should note that the higher the water
temperature, the greater the respiration rate of inhabit-
ing organisms. They should also realize that water retains
more oxygen at lower than at higher temperatures. Animals
can therefore tolerate lower oxygen concentrations longer
at lower temperatures. Managers must not forget that in
an estuary they also must concern themselves with varying
salinities. The higher the salinity., the lower the oxygen
saturation level and the greater the respiration rate. It
is obvious therefore that a decision based on conditions
in the upper regions of an estuary cannot necessarily be
applied to a problem at its mouth. It is true that oxygen
is less affected by.changes in salinity than by changes in
temperature, but their combined action can reduce oxygen
concentration to such an extent that a disaster will occur
(Moore, 1958).

CARBON DIOXIDE''AND pH
Harvey (1945) discovered that sea water contains more
alkaline radicals than strong acid radicals. This base
excess is important because it retains a carbon dioxide
reserve, in the form of bicarbonate and carbonate, for
use in photosynthesis. With this reserve a faster photo-
synthetic rate is possible and more food and oxygen are
released for animal consumption (Day, 1951). This excess
base also acts in a buffering capacity in estuarine waters

Appendix 15
47

to prevent pH chan es caused by th e addition of acids
or bases (Reid,,1991).

The pH of surface sea water ranges between 8.1 and
8.3 and is very stable (Reid, 1961). The pH of the mouth
of an estuary is within this range., but more variation
exists in the upper reaches of an estuary where the
river systems enter. The water of a river trans-
porting large quantities of humic material in colloidal
suspension is slightly acidic in nature. As this water
enters the estuary and contacts higher salinities, the
colloidal particles flocculate, causing the pH range to
shift toward that of normal sea water (Reid, 1961).
Flocculation per se was described in the discussion on
sedimentation.

Generalities regarding the interrelationships of
carbon dioxide (C02). pH and oxygen are that the dis-
tributional pattern of C02 is expected to be the reverse
of oxygen and that pH is expected to vary inversely to
free C02 content and directly to dissolved oxygen con-
centration (Day, 1951; Reid, 1961). Low pH is found in
the areas of abundant organic matter because bacterial
decomposition ofthis material releases carbon dioxide.
High pH is found in areas where plants are abundant
because of oxygen production (Reid, 1961).

Moore (1958) did not consider pH as an important
limiting'factor. However, his examples were restricted
to individual species studied in the laboratory. Again
it must be emphasized that limiting factors rarely ever
act alone. Their combined effects on biological communities
have been researched only to a limited extent.

TEMPERATURE, SEASONALITY, AND LATITUDE

The effects of temperature, latitude and seasonality
on estuarine biota are interrelated to such an extent
that they are extremely difficult to separate., For this
reason, these physical factors will be considered together.

Estuaries are covered by a relatively thin layer of
water in comparison to the ocean and therefore are affected
more by atmospheric temperature variations (Emery and
Stevenson, 1957a). Because the mouth of an estuary is
close to the sea, it has a relative stable temperature
as compared with the upper reaches'of an'estuary, which

Appendix 15
48

are considerably affected by meteorological conditions
and somewhat affected by the temperatures of the rivers
draining into it.

Some beat is required by all organisms for the
functioning of metabolic processes (Kinne., 1970). These
processes are restricted, however, to a particular tem-
perature range. Kinne (1970) stated "with regard to life
on earth temperature is - next to light - the most important
environmental component". Temperature affects living
organisms in three basic ways: (1) "It determines the
rate and mode of chemical reactions and hence biological
processes, (2) it affects the state of water., the basic
life-supporting medium, and (3) it modifies basic prop-
erties of living matter" (Kinne, 1970).

Investigations have shown that the total number of
marine invertebrate species increases from.the polar region
to the tropics; the species with pelagic larvae increase
up to 85% (Thorson, 1957). A seasonal effect associated
with upper latitudes is that the benthic. intertidal organisms
may freeze or ice may scour them away. It has been shown
that the metabolic rates for a particular species found
in both the northern and southern latitudes is about the
same (Thorson, 1950; Bullock, 1955; Dehnel, 1955). These
studies have also demonstrated that if comparison is made
of organisms from southern and 'northern latitudes retained
at the same temperature in the laboratory, then the more
northern organism will have a higher metabolic rate.

Dehnel (1955) studied growth in a shallow-water
euhaline gastropod in areas separated latitudinally by
1900 miles. His investigation revealed that the growth
rate of encapsulated embryos and larvae was two to three
times greater in the northern latitude than that of the
southern populations at comparable temperatures. Carriker
(1967) implied that this increased growth rate might have
been a latitudinal effect, but Dehnel (1955) speculated
growth effects (e.g., better yolk quality) in the northern
sphere of the study.

In the Chesapeake Bay the annual temperature range
is from about OOC to approximately 290C (Bumpus, et al.
1973). Schubel (1972) demonstrated that temperatures in
the Virginia region of the Bay avarage about 0-50C warmer
than in the Maryland region.

Appendix 15
49

A large volume of literature is available on tem-
perature effects on individual marine and brackish water
organisms, but extensive literature on the effects of
temperature on the supra-organismal level (e.g., eco-
system or community) does not exist. One exception to
this statement is that some information on microbial
ticommunities" is known, but corresponding information
on the individual bacteria comprising these colonies is
not known.

Certain generalities regarding the effects of tem-
perature on biota have been determined. For example, at
summer temperatures in the temperate latitudes, certain
mollusks have higher mortality rates when the salinity
level decreases. However, if the temperature is low and
the salinity remains low, they can survive for a longer
period of time (Carriker, 1967). In contrast, some
transient crabs and shrimps can survive at low salinities
when the temperature level is high (Pearse and Gunter,
1951: KinneS 1964).

In 1972, the Chesapeake Bay softshell
clam industry suffered considerably from the salinity
decrease caused by Tropical Storm AGNES. The.situation
grew worse at the onset of a heat spell. The clams were
therefore stressed by both low salinities and high tem-
peratures. Their respiration rates increased, forcing
them to pump water even though normally they could cease
pumping, thereby avoiding adverse environmental conditions.
All of these examples display the interaction of salinity
and temperature.

Temperature causes a variation in water density,
resulting in changes in stratification and the circulation
rate in a two-layered estuarine system such as the Chesapeake
Bay. Since the surface layer of the water is alternately
warmed and cooled throughout the year, several vertical
temperature structures are possible. Seitz (1971) pos-
tulated four, and observed three, temperature-salinity
structures for the Bay: "From March to August warm-fresh
water overlies colder-saltier water. From September t*o
December cold-fresh water overlies warm-saltier water.
During January and February cold-fresh water overlies
cold-saltier water. The fourth possibility of warm-fresh
water overlying warm-saltier water may be a temporary
condition near the end of August or early September"
(Bumpus,. et al. 1973).

Appendix 15
50

Although some information on the hydrodynamics of
non-tidal water circulation is known, no attempt has
been made to relate it to the spawning of benthos in late
spring and early summer in the temperate and bor 'eal regions
(Carriker, 1967). Neither has the relationship between
seasonal change in the temperature of an estuary and the
migration of animals to and from the sea been studied.
The movement into and out of an estuary is related to
feeding and spawning requirements of the migrant organisms.

The migration of some fishes and decapod crustaceans
appears to be related to both temperature and salinity
factors; salinity tolerance is greater at higher temperatures
(Day, 1951). Broekema (1941) demonstrated that Crangon
crangon (a shrimp) is more dfficient in its osmotic regu-
lation at higher than at lower temperatures. This animal
can therefore maintain, at higher temperatures, a greater
difference between its internal salt concentration and
that of the surrounding water (Day, 1951).

NUTRIENTS

Moore (1958) believes that most of the elements required
by estuarine organisms are present in sufficient enough
quantity that they need not be considered as limiting
factors. Concentrations of trace elements are probably
more significant than concentrations of nitrogen, phos-
phorus or silica. Lund .(1969) stated that phosphorus
and nitrogen deficiencies in lakes may not be as important
as excess quantities of these elements. Excesses may cause
eutrophication. Although eutrophication can be beneficial,
if enrichment occurs too quickly, the body of water involved
may suffer. "Artificial" eutrophication sometimes elim-
inates desirable species, encourages the growth of obnoxious
algae and causes anoxic conditions from the decay of intro-
duced material and of dead organisms (See p.393 for a more
detailed discussion).

Phosphorus is present in an estuary only as a phosphate
compound (Kinne, 1970). In living tissue (e.g.; phytoplankton)
this element is mainly found in organic compounds. It is
released back into the water in particulate or soluble form
either by excretion or by decay of the organism after death
(Moore, 1958). Figure 15-12 illustrates a highly simplified
model of the phosphate cycle within a relatively isolated,
4-
water mass.

Appendix 15
51

ORGANIC PHOSPHATE

I,u'TOLYS.,S

DIFFLIS1014, 1.11YING DIFFUSION. MIXING
LOSSE5 AND ACCESSICINS LOSSES AND ACCE3SIONS

SOLUELE jj:OLO G]CAL PARTItUL ATE
ORSANiG onrVA-11111C (a)
FHOSMIATE SIVITIJESIS PHOSMATE

(A)
INOMANIC

FHOSPHATZ'

DiFFUSION, MIXING
LOSSES A!aO ACCESSION'S

FIGURE 15-12: SIMPLIFIED CYCLE OF PHOSPHORUS
TRANSFORMATION (Emery and Stevenson,
1957a)

Rochford (1 951a., 1951b) reported that in deep waters
where there is not sufficient light for growth or oxygen
for animal respiration, phosphorus concentrations tend
to increase (Emery and Stevenson., 1957a). This increase
is partially caused by the release of phosphate from the
sediment after anaerobic bacterial decomposition of the
organic material (Stevenson, 1951). Phosphate concen-
trations also tendto increase from the mouth of an
estuary to its head because rivers discharge high concen-
trations of phosphorus into a bay.

In general nitrogen, like phosphorus, increases with
depth (Collier, 1970). Four processes occur in the
utilization of nitrogen: nitrogen fixation, nitrification,
denitrification and ammonification. Details of'these
cycles are well known for terrestrial regimes., but little
is known about them in aquatic systems (Collier, 1970).
A great deal of research on specific organisms and their
biochemistry is needed in order to fully understand all
the nitrogen pathways in an estuary. A generalized scheme

ADDendix 15
52

of the nitrogen cycle in the ocean is illustrated in
Figure 15-13 (C61lier, 1970). It is important to recognize
that an estuary can receive both elemental nitrogen and
nitrate from the atmosphere (Moore, 1958). Different
sources of nitrogen can be utilized by different organisms,
but many prefer nitrate. Nitrogen and phosphorus may act
as limiting factors in freshwater tidal marshes. It has
been discovered recently that nitrogen is more likely than
phosphorus to limit growth of phytoplankton in coastal
waters (Flemer, 1972).

LANOr
RAIN VPAINAG

Nn
r 3
ORG.,mic tAITRO*EN
P
NTS
LA
N2 ;;X-
PIL A% rs--*.A%"r.4ALS HIS RIVKAV #ON
PLANTS
"?3
Z
PHOTIC

APHOTIr-
AWMONIFICATtO.4

N;t;4 'EN
N FIX&TIO"I N"3
;I 'f -
0EqIT
02
NO3
FiC,mic:j

NITAIF;,'AtION
'Y'X)

CR"NIC

2 PLAIIT-AN.MAL "N3
RESICUCS

ANAEROBIC ENttRonmENr
IN SEOWENTS

RE rRAZ COW

PESIOU-M

FIGURE 15-13: tHE ORGANIC CIRCULATION OF NITROGEN IN THE OCEAN
(Collier, 1970)

Appendix 15
53

Silica, in the form of silicate, has been found in
higher concentrations in Chesapeake Bay than in the surface
water of the ocean (Emery and Stevenson, 1957a). Diatoms
utilize silica to build their frustules. If the concen-
tration of silica is limited, they possess thinner walls
(Moore, 1958). Little else is known about the effect of
low concentrations of silica on organisms.

Other nutrients apparently important to the survival of
organisms are iron, manganese, potassium, bromine, vanadium,
and beryllium. The effects of these elements as limiting
factors have not been studies intensely, but managers
should recognize their importance.

BIOLOGICAL FACTORS

Up to this point limiting factors have been discussed
mainly in the physico-chemical sense. Now attention is
being turned to biolo&iical "limiting factors." This
discussion will involve topics in most biological sdience
subdivisions (e.g., physiology, ecology, biochemistry).
It is inherent that biological factors are.intimately
associated with physicochemical factors. Limiting bio-
logical factors will be discussed mainly in regard to the
concept of trophic relations, i.e., in community metabo-
lism. When various ecological concepts were discussed
earlier,. the various trophic levels of producers, con-
sumers, and decomposers were mentioned; they will form
the basis of this discussion.

Food webs and/or food chains indicate the organisms
involved and the energy flow sequence in a particular
biological system., Water flow, invisible pathways of
physical and chemical elements, and various organiza-
tional mechanisms which interrelate the parts are all
involved (Copeland, 1970). Material flow is cyclic
whereas energy flow is linear: it flows from the green
plants through the various levels of consumers to the
bacteria, fungi, and other microorganisms (Figurel5-14).
An ecosystEm (or major conmmity) is dependent upon only one
outside energy source, solar energy. Vertically, then,
an ecosystem is divided into two major zones dependent
upon the light energy entering the system. In the upper
zone, the dominant process is photosynthesis whereas in
the lower, more shaded zone, food consumption and con-
sequently mineral and carbon dioxide release are the
dominant processes (Copeland, 1970).

Append ix 15
54

gl xTpua

rri

z 0
c M
Oxw.
n rn z
CL'o
C-3

OQ
00

F-I

F-A

z >
rn
M
t3d

:r
-<
rn 0
M 0
06 V
1A
c r
c
3 OQ
co

rn-<
z(a

txj 4
m >
0
m

rn
(D QQ ock 0
0 go 0) co
3 2. m
4A 7(a =
3 (D
U, 0)
m
3 0
"14

IV c
0

It is necessary to understand primary productivity,
community pr6duction and respiration in order to under-
stand the functioning of energy flow in an ecosystem.
Primary productivity is the energy fixe&11by,photosynthesis
and chemosysthesis as organic material. The existence of
all other organisms is dependent upon the production of
this material. Respiration is used here in its broadest
definition, i-.e., the respiratory consumption of food
and oxygen which measures the magnitude of work involved
in self maintenance (loss of energy) (Copeland, 1970).
Community production, including both primary and secondary
productivity, under stabilized conditions equals community
(i.e., both plants and animals) respiration. If community
production (P) exceeds community respiration (R), then
organic material accumulates in an estuary. If R exceeds
P, then energy is lost from the system (Swartz, 1972).
If a community is in an early stage of development or is
disrupted in some manner, (e.g., addition of pollutant)
then the P/R ratio is less than or greater than unity.
The most efficient energy pathways are, therefore, not
being used. Measurement of these two factors, production
and respiration, and determination of their inequality
can provide valuable evidence of environmental change
(Odum, 1969; Swartz, 1972).

Vascular plants (e.g., eelgrass, marsh grass) are a
major source of primary productivity in an estuary.
This plant material decomposes and enters the water as
organic detritus. Decomposition occurs slowly enough
that a continuous supply of food is available. Useful
nutrition is provided mostly by the bacteria, fungi,
protozoa, micro-algae, etc., adsorbed onto this de.tritus.
Diatoms and filamentous green algae are known to provide
10 to 20% of the diet of many detrital feeders. For this
reason, Odum (1970) feels that these feeders should be
called "detritus-algal consumers." Amphipods, isopods,
mysids, small crabs, insect larvae, caridean shrimp and
some fishes use detritus and absorbed microorganisms as
their principal source of energy. In addition, this
material serves as an emergency food supply for other
organisms when their normal food source is.not available.
A predator often can sonsume detritus and survive, but
its growth rate will be hampered (Odum, 1970).

Phytoplankton form the base of an important esutarine
food chain (Figure 15-15). Some juvtnile estuarine fish,
spawned at sea, feed on zooplankton. As they migrate,
into an estuary, they continue to use zooplankton (which
.feed on phytoplankton) as their primary food source. They
gradually shift their feeding habits to benthic organisms,
plants and detritus (Odum and Copeland, in press; Odum,1970).
This example illustrates another important principle of

Appendix 15
56 .

Fish that shepherd fish

Navicula

Thalassiothril

Channel Bass
peridinium Fragilaria
pajass@qslra

V y
A.

Rhizosolenis

Coscinodiscus

Goniaulax Alewife

Light using Phytoplankton microscopic

Pseudocalanus
Menhaden
elongatus

Centropages

typicus

%
Acartia clausi Fish that eat zooplanktan

Thread Herrin
I e, 9

(D phytoplankton Temora longicarnis
eating Zooplankton Imm
Micro -organisms decomposing waste FTGURE 15-15: COMPONENTS OF A PLANKTON BASED FOOD CHAIN
11. ridified from Odum and Copeland (1974)

energy flow. An effective ecosystem circulates the products
of one trophic level to ano-ther, either by taking advantage
of naturally occurring circulation patterns or by organism
movement (Copeland, 1970).

It should be recognized that energy is naturally lost
as unavailable heat during'each biochemical reaction. In
addition, potential energy is lost when clommercial species
are harvested, when migratory forms move out of the estuary,
and When organic matter is buried and removed permanently
from participating in the chemical reaction of the system.
If man interrupts an established energy flow, he may cause
additional energy losses as well as other detrimental
biological effects. The decline or demise of a desirable
speeies may occur, or its niche may be claimed by a less
desirable species as a result. Man's activities may cause
the loss of a marsh area and/or detritus-producing area,
resulting in a decline of the organisms which primarily
feed on detritus. A loss of this nature directly affects
the next higher trophic level, thereby starting a chain
reaction throughout the food web.(Odum, 1970).

Estuarine food chains are vulnerable to interrruption
apparently because they are basically short and simple
(refer back to Figure 15-15) (Odum,,1970). Generally,
in estuaries, there is a great deal of dependence of
larger organisms on a few key smaller organisms that
utilize detritus and micro-algae for food.

A classic example of the effects of man on a food
chain is demonstrated in "The Great South Bay Duck Farm
Incident" (Ryther, 1954). Duck farms we re established
on the tributaries of the Great South Bay in Long Island
Sound, New York. As a consequence, a great amount of duck
manure was flushed into the Bay, Low circulation allowed
it to accumulate, causing artificial eutrophication andi
consequently, algal blooms. The type of producers present
shifted. Prior to the establishment of the duck farms,
the phytoplankton consisted of mixed diatoms, green flag-
ellates and dinoflagellates. These dominant organisms
were replaced by small green flagellates of the genera
Nannochloris and Stichococcus. Becuase they could not
utilize these flagellates as food,,oysters which had
lived in the Bay for years began to decline in abundance.

Trophic relationships represent only one aspect of
species interactions occurting in an estuary. Species
interaction refers to the sum total of all interspecific
and intraspecific relationships of the biota, including
food procuring, mating and reproducing, spacing between
organisms, shelter seeking and physiologically adapting

ADnendix 15
58

to surrounding physico-chemical parameters. All of
these processes are significant at some stage in the
ecological life history of an organism.

The changes as a result of successful artificial intro-
duction of species into an established estuarine system
are dependent primarily upon species interactions. Although
these introductions may be beneficial, they have also
harmfully affected existing communities. For example,
Gryphea (Crassostrea) angulata, the Portuguese oyster, was
transplanted into English waters, but inadve@tently intro-
duced at the same time was Urosalpinx cinerea, an oyster
drill now recognized as an extensive predator. A presebt
,threat to the James and Delaware Rivers is the Chinese
clam, Cordicula manilensis, which clogs industrial intake
pipes and causes significant pollution problems by periodic
mass die-offs and decay (Boesch, personal communication).

Extensive research on the interactions of organisms is
definitely needed. Some interesting information has already
been learned, e.g., that chemicals released into the water
by some species attract their own kind. It has been pos-
tulated that this chemical release provides the basis
for the development of oyster bars. On the contrary, some
species repel by various methods settling of their own
kind. Thorson (1957) noted that Spisula larvae are
attracted to clean sand. Once settled, their feces accu-
mulate and act as an inhibitor to the settling of other
Spisula larvae (Carriker, 1967). It is known that many
planktonic larvae "explore" the bottom in order to find
one suitable for metamorphosis (Carriker, 1967). The
environmental clues detected by an organism indicate,
whether or not the bottom is a suitable one on which to
settle. Additional research is needed to thoroughly
understnad this mechanism. Managers should recognize
that survival time of larvae is limited. If they are
unable to find a suitable substratum on which to develop
further, they will die. The greater the number of unstLit-
able habitats in the Chesapeake Bay, the greater the reduc-
tion in kinds and numbers of individuals, and consequently
in communities.

This chapter has attempted to provide a basis for under-
standing an appreciation of the intricacies of the Chesa-
peake Esttary. If a bridge can be provided between know-
ledge of physical, man-induced changes, and resulting
anticipated effects on the estuarine biota, both short
and long-term and both monetary and non-monetary interests
can be served, inhanced and protected in the interest of
all generations of BkLy Area citizens.

Appendix 15
59

CHAPTER IV

IMPORTANT SPECIES IDENTIFICATION

As a result of increased competition by man for use of
natural resources, biological integrity has often been
compromised in Chesapeake Bay. Managers are in need of
biologists' knowledge concerning the relationships between
organisms, their environment, and the effects of man-
induced changes, as discussed in Chapter III.. It was
felt that a key second step toward this goal would be an
identification of "important" species in the Bay.

Therefore, as a part of the Chesapeake Research Consortium
(CRC) effort referenced earlier, a survey was conducted
of prominent Bay Area scientists (see Table 15-2) to solicit
.their candidate for the important species. As stated by
Hayes T. Pfitzenmeyer, of the University of Maryland,
coordinator of the inventory:

"The task of selecting the important species is
formidable when one considers the biological com-
plexities of the Chesapeake Bay system. Individ-
ual species and their relationships with each
other, their associations with unrelated species,
their direct value to man, and the effect they
have on the environmental community are but a
few of the more perceptible considerations
which must be weighed. The state of our know-
ledge on any one of these aspects is not com-
plete, and much research remains to be done
before our understanding of the interrelation-
ships and importance of individual species is
final.

"With these facts in mind, we have attempted
to complete a list of those species in the Bay
system which, so far as our knowledge exists,
are important for water resource management

Appendix 15
61

TABLE 15-2
LIST OF SCIENTISTS RESPONDING TO QUESTIONNAIRE

Dr. Richard Anderson American University, Wwashington, D.C.
Dr. Jay Andrews Virginia Institute of Marine Science
Gloucester Point, Virginia
Dr. John Bishop University of Richmond, Richmond.,
Virginia
Dr. Donald Boesch Virginia Institute of Marine Science
Gloucester Point, Virginia
Dr. T., E. Bowman Smithsonian Institution, Washington,
D.C.
Dr. Robert Burchard University of Maryland, Baltimore,
Maryland
Dr. Victor Burrnell Dept. of Wildlife, Charleston, South
Carolina
Dr. Martin Buzas Smithsonian Institution, Washington,
D.C.
Mr. David Cargo Chesapeake Biological Laboratory,
Solomons, Maryland
Dr. Rita Colwell University of Maryland, College Park,
Maryland
Dr. George Grant Virginia Institute of Marine Science
Gloucester Point, Virginia
Dr. Donald Heinle Chesapeake Biological Laboratory,
Solomons, Md.
Dr. Harold H. Humm, University of South Florida, Tampa.,
Florida
Dr. H. P. Jefferies University of Rhode Island, Kingston,
Rhode Island
Dr. Frederick Kazama Virginia Institute of Marine Science
Gloucester Point, Virginia
Mr. James Kerwin Patuxent Wildlife Center, Laurel,
Maryland
Dr. Donald Lear Environmental Protection Agency,
Annapolis, Maryland
Mr. Robert Lippson National Marine Fisheries Service,
Oxford, Maryland
Dr. Frank Maturo University of Florida, Gainesville,
Florida
Ms. Patricia Orris University of Maryland, College Park,
Maryland
Dr. Franklyn Ott Virginia Institute of Marine Science
Gloucester Point, Virginia
Mr. Charles Rawls Chesapeake Biological Laboratory,
Solomons, Maryalnd

Appendix 15
62

TABLE 15-2 (cont'd)
LIST OF'SCIENTISTS RESPONDING TO QUESTIONNAIRE

Dr. Colin Rees University of Maryland, College Park,
Maryland
Mr. William Shaw National Marine Fisheries Service,
Oxford, Maryland
Dr. Eugene Small University of Maryland, College Park,
Maryland
Dr. Victor Sprague Chesapeake Biological Laboratory,
Solomons, Maryland
Dr. Stephen Sulkin Chesapeake Biological Laboraotry,
Solomons, Maryland
Dr. Frank Schwartz University of North Carolina,
Morehead City, N. C.
Mr. W. Van Engel Virginia Institute of Marine Science
Gloucester Point, Virginia
Dr. Marvin Wass Virginia Institute of Marine Science
Gloucester Point, Virginia
Dr. Austin Williams Smithsonian Institution, Commerce
Department, Washington, D.C.

.Appendix 15
63

purposes. Asisstance in selecting these
species was sought by questionnaires sent
to scientists who were-familiar with a par-
ticular group or groups of Chesapeake Bay
flora or fauna. A copy of the questionnaire
and accompanying letter is included as
Attachment 15-A. Several species were
listed on the form for consideration when
it was sent to the respective authorities
and they were requested to add and evaluate
other species which they believed important."

Table 15-3 lists the 126 species representing 12 phyla
considered important to the Bay for water resource
management purposes. Each species was carefully examined
for its inclusion in the list. An attempt was made at
first to assign a numerical value to each of the 15 cri-
teria on the questionnaire and to use this method as a
menas of selecting important species. This was later
rejected for several reasons. The relatively few criteria,
purposely kept at a minimum to get maximum response, and
the decision to include any speties if it qualified for
one of several criteria, made an empirical evaluation
probably just as valid. For example, a species would
qualify as an "important species" if it were either a
commercial species, a species pursued for sport, a
prominent species important for energy transfer to a
higher trophic level, a mammal or bird protected by
Federal Law, or if it exOrt0d a deleterious influence
on other species important to man.

In addition to these criteria, many others entered into
the selection process. Several species were eruptive in
their reproduction and thus great ecological sig4ificance;
others were tolerant of pollution or nutrient enrichment
to the point of being a nuisance. Many, particularly
fishes and birds, are migratory and thus their significance
is felt only seasonally. Zoogeography of the estuary was
considered in attempting to find species representative
of as many areas and habitats as possible, including fresh-
water tidal reaches. Some species were listed because
they were introduced or had recently undergone a rapid
increase. Some have been chosen for significance in
certain communities, particularly the wetlands and eelgrass
communities.

ADDendix 15
64

TABLE 15-3
IMPORTANT CHESAPEAKE BAY SPECIES

Common Name Scientific Name Importance

Algae

Blue-green alga Anacystis.spp. Nuisance
Food chain
Diatom Skeletonema costatum
Diatom Rhizosol a spp. Food chain
Diatom Nitzschia spp. Food chain
Diatom Chaetoceras spp. Food chain.
Dinoflagellate Polykriko-s--kofoidi Toxic
Dinoflagellate Cochlodinium hete7olobatum Toxic
Dinoflagellate Gymnodini'Um splendens Toxic
Sea lettuce Ulva lactuca Nuisance
Green alga Enteromorpha spp. Nuisance
Red alga AgarJh'1ella tenera Cover

Vascular Plants (Marsh and aquatic)

Widgeongrass Ruppia maritima Food chain
Cordgrass @@p-artina alterniflora Food chain
Eelgrass Zostera marina Food chain
Horned pondweed Ta-H-n-TE-Ne-11-1apalustris Food chain
Wild rice Zizania iquatica Food chain
Cattails. _T_Vyp`E`aspp. Cover
Pondweeds Potamogeton spp. Food chain
Arrow-arum PeltandrT-virRinica Food chain
Wild celery Vallisner-la spirali .s Food chain

Cnidaria

Stinging nettle Chrysaora quinquecirrha Nuisance
Hydroid. bertularia argentea Nuisance

Ctenophora (comb jellies)

Comb jelly Mnemiopsis leidyi. Predator
Comb jelly Beroe ovata Predator

Appendix 15-
65

TABLE 15-3 (cont'd)
IMPORTANT CHESAPEAKE BAY SPECIES

Common Name Scientific Name Importance

Platyhelminthes (flatworms)

Flatworm Stylochus ellipticus Predator

Annelida (Worms)

Bloodworm Glycera spp. Food chain
Polychaete worm Nephtys spp. Detrital breakdown
Clam worm Nerels succinea Food chain
Polychaete worm @a ri-onospio pinnata Detrital breakdown
Polychaete worm Scolecoluides viridis Food chain
Polychaete worm Polydora ligni Nuisance
Oligochaete worm limnodrilus spp. Detrital breakdown

Mollusca (Shellfish)

Eelgrass snail Bittium varium Food chain
Oyster drill !@r-osalpi-nx cinerea Predator
Marsh periwinkle Littorina irrorata Food chain
Hooked mussel Brachidon-tes recurvus Food chain
Ribbed mussel Modiolus issus Food chain
Oyster Crassostrea virginica Commercial
Hard shell clam Mercenaria mercenaria Commercial
Coot clam Ru-Iinia-lateralis Food chain
Brackish water clam Rangia cuneata Food chain
Balthic macoma Macoma Va-IFFI-ca Food chain
Stout razor clam Ta-g-e-T-us plebius Food chain
Razor clam P7nsis directus Food chain
Soft shell clam Mya arenaria Commercial
Asiatic clam U-o-Fbicul@--manilensis Nuisance

Arthropoda (Crabs, shrimp, and other crustaceans)

Barnacle Balanus eburneus Nuisance
Copepod Eurytemora-afT-1-nis Food chain
Copepqd Acartia spp. Food chain
Opposum shrimp Reomysis americana Food chain
Cumacean Leucon americanus Food chain

Append-ix--15
.63

TABLE 15-3 (cont'd)
IMPORTANT CHESAPEAKE BAY SPECIES

Common Name Scientific Name Importance

Arthropoda (Continued)

Isopod Cyathura @Olita Food chain
Isopod Paracerceis caudatum Food chain
Amphipod Ampithoe T@ni-imana Food chain
Amphipod Ampelisca spp. Food chain
Amphipod Corophium spp. Food chain
Amphipod Leptocheirus plumulosus Food chain
Amphipod Gammarus spp. Food chain
Sand flea Talorchestia.longicornis Detrital breakdown
Grass shrimp aemonetes puglo Food chain
Sand shrimp Crangon septemspinosa Food chain
Xanthid crab N opanopa sayi Scavenger
Xanthid drab Rhithropanopeus harrisii Scavenger
Blue crab calij-prtes sapidus Commercial

Urochordata

Sea squirt Molgula manhattensis Nuisance

Pisces (Fish)

Cownose ray Rhinoptera bonasus Predator
Eel Anguilla rostrata Commercial
Shad, herring Alosa spp. Commercial
Menhaden R-revoortia tyrannus Commercial
Anchovy Anchoa m1-tcR-1Tr1- Food chain
Variegated minnow Cyprinodon variegatus Food chain
Catfish, bullheads I-ctalurus spp. Commercial
Hogchoker Trinectes maculatus Predator
Killifish, Fundu.1us spp. Food chain
Silverside Menidia menidia Food chain
White perch Rorone americana Commercial
Striped bass R-orone saxatilis Commercial
Black sea bass U-entropristis striata Commercial
Weakfish @Znoscion regalis Commercial
Spot Leiostomus xanthurus Commercial
Blenny Chasmodes--bUsquianus Food,chain
Goby =010soma spp. Food chain
Harvestfish Peprilus paru Predator

Appendix- 3-5
67@

TABLE 15-3 (cont'd)
IMPORTANT CHESAPEAKE BAY SPECIES

Common Name Scientific Name Importance

Pisces (Fish) (Continued)

Flounder Paralichthys dentatus Commercial
Northern puffer Sphoeroi es m-ac-u-1-a-tus Commercial
Oyster toadfish Opsanus tau Predator

Reptiles

Snapping turtle Chelydra s. serpentina Commercial
Diamond-backed
terrapin Malaclemys t. terrapin Commercial

Aves (Birds)

Horned grebe Podiceps auritus Protected
-Cattle egret Bubulcus- ibis Protected
Great blue heron Ardea her-o-Ti-as Protected
Glossy ibis @@adls falcinellus Protected
Whistling swan Olor coTum-F-lanus Protected
Canada goose F-ranta canaden-Rig Game
Wood duck Tix s2onsa Game
Black duck TH-as acuta Game
Canvasback TY-TNyi valisineria Game
Lesser scaup Aythya affinis Game
Bufflehead B!ice@ha_1_a_a_1_Fe_ola Game
Osprey Pandion h'aliaetus Protected
Clapper rail Rallus 1 ris Game
.Virginia rail Rallus limicola Game
American coot Fulica americana Game
American woodcock -PE-1-1-o-FeYa @minor Game
Common snipe. Capella Game
Semipalmated sand-
piper Ereunetes pusillus Protected
Laughing gull Larus Ttricina Protected
Herring gull Ua-rus argentatu's Protected
Great black-backed
gull Larus marinus Protected
Forster's tern @T_te_rna_ro_rsteri Protected
Least tern Tt-erna -allb-irr-ons Protected

Appendix 15
68

TABLE 15-3 (cont'd)
IMPORTANT CHESAPEAKE BAY SPECIES

Common Name Scientific Name Importance

Mammalia (Mammals)

Beaver Castor canadensis Commercial
Muskrat U-nd"atra zibethicus Commercial
Mink gu-stela vison mink Commercial
Otter rutra canadensis Commercial
Raccoon Fr-ocyo-n-To-tor Commercial
White-tailed deer ME-coile-usvirginianus Game

'Endangered species

Shortnose sturgeon Acipenser brevirostrum. Potomac River.
Atlantic sturgeon A-ci-penser oxyrhynchus. Anadromous, juveniles
estuarine all year.
Maryland darter Etheostoma sellare. Endemic to Swan Creek,
near Havre de Grace.
Southern bald eagle Haliaetus leucocephalus leucocephalus.
Generally decreasing.
-American peregrine falcon Falco peregrinus anatum. Decreasing,
extirpated as a breed_i_n-g_'Fi_r_J in-Eastern U. S.
Ipswich sparrow Ammodramus sandwichensis princeps. Rare dune
nester; winters in Urginia.
Delmarva fox squirrel SCiUTUs niger cinereus. Occurs only on
Eastern Shore of R-a-r-y-f-and, mostly in counties bordering
Chesapeake Bay. Endangered by development.

Appendix 15
60

CHAPTER V

BIOLOGICAL.SUMMARIES OF
SIGNIFICANT BAY ORGANISMS

'Of the 126 species identified as "important" in Chapter IV,
.funding constraints permitted a detailed examination and
life history summaries of only 32 individual species.
Eight of these summaries were included in the "Sample
Inventory" (Tables C-VII-15 through 22) of the Existing
Conditions Report. The species discussed were Corollospora
pulcEella (ascomycete fungus); Ruppia maritima (ditch-grass);
.Myriophyllum s@icatum (Eurasian watermilfoil); Acartia
tonsa (dopepod); Chrysaora quinquecirrha (stinging nettle);
Mya arenaria (soft-shell clam); Sagitta elegans (arrow
worm); and Hyla cinerea (green tree frog).

An additional 24 spedies are presented in this report.
The summaries were prepared by persons familiar with
the particular species or group. Summaries of the biology
of these species were taken from the literature, either
published or unpublished, and from the knowledge of the
person writing the inventory. Included are a .-enus of
diatoms, 9 invertebrates, 5 fish, 2 turtles, and 7 birds.

Guidelines for systematic compilation of information
on Chesapeake Bay organisms were proposed by L. C. Kohlenstein
in 1972.(l) It will be of value, he wrote, "to scientists
seeking information on species unfamiliar to them, to
modelers attempting to pull together a broader understand-
ing of the function of an ecosystem, to scientists,
engineers, and resource managers attempting to assess
the impact 6f a proposed change affecting the Bay." He
proposed an outline to be followed for compiling descrip-
tive ecological information on biological entities. it

(1) Kohlenstein, L. C. 1972. Systems for storage,
retrieval and analysis of data. Chesapeake Sci.
13 (Suppl.): 157-168.
Appendix.15
71

was the opinion of those completing the outline that
much modification was needed since it was not suitable
for all phyletic groups. It is doubtful if any one
outline, with sufficient detail to be of any value,
can fit all of these groups.

The species summaries prepared for this report follow
the general outline as proposed by Kohlenstein.
Although category numbers have been omitted to save
space, the order is the same. The specialists pre-
paring the summaries were given liberty to modify the
form to fit the entity with which they were working.

The completion of these biological summaries of several
important Bay organisms contributes to our pool of
readily accessible information which may be used by
scientists, engineers, or laymen. Now that a fourth
of the 124 species defined as mott important in the
Chesapeake Bay have been summarized, it is hoped that
the rest may be similarly treated in the near future.

Appendix 15

Category: Lower Plants *In order to save space, numbers
are used for citations in this
summary - Editor

Common Name: Diatom

Inventory Prepared b Daniel E. Terlizzi
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification

Phylum: Chrysophyta
Class: Bacillariophyceae
Order: 'Centrales
Family: Chaetoceraceae
Genus: Chaetocerus (Ehrenberg, 1844)
Species: Griffith-(2) described 23 species.
Present review of literature indicates 43 species (Table 15-4.)

Distribution

Known range: Cosmopolitan
Distribution in Chesapeake Bay: Poole's Island to mouth-of
Bay extending over Continental Shelf.

Population

Reproduction (see generic description)

Life Stages

Physical appearance: Cells with oval section to almost or
rarely completely circular in valve view; in broad girdle
view quandrangular with straight sides and concave, flat,
or slightly convex ends. Valve with a more or less flat
end surface or valve surface and a cylindrical part or
valve mantle which are bound together without a seam. A
long thick or thin seta, bristle or awn, at each end of
the long or apical axis of the valve on the corners, The
opposite setae of,neighboring cells touch one another
near th6ir origi 'n, usually directly or sometimes by a
bridge, and fuse firmly at a point near their base hbld-
ing the cells in chains, usually with large or small
.apertures or foramina between the cells. Basal portion
of the setae parallel to the pervalvar axis, or directed
diagonally butward with the outer portion frequently
perpendicular to the axis of the chain. In most species,
the length of the chain is limited by the formation of
special end cells,,'terminal setae, usually shorter and
thicker and more nearly parallel to the chain axis than.
the others. In relatively few species are cells solitary.

Appendix 15
73

PL
gl xTpuaddV

ci C') n Cl) C"i n

cr C7.
n 03
H 0 C+ CD cn
0.1 0 v
lu .4 CD
p n
0 tA C+ H. C+ I-
(A H. w 0 CD
to n H (A
0

C-) C-) t- t- 00 t- t-
o 0 ID 0 0 0 0 0 0 0 0 0 0 go 0 0
V, t & t 0 t r. 1-@ t :c C+ t V. t-
CD CD C+ CD C+ o t14 .4 C+ -<m m 0 CD CD 0
H ::r 1-10 CD -r (D 0-1H >4 $4 H n
H 0
0 w 0 w (D C+ 0 C+ w w 0 w
w w ::%
m P) C+ @-h ID t-h SD r+ 0) m

En
Pool

-3

@-30
0 0
C: . 2 m F@
00 0% 00 CD Ul C> ul @-4 CD cn Ul 040 co -4 -4 0 t-n

z @o z @o C-4
0
0 p I I I En
TF- pi
CD 0 CD x

X x ra
cr

CD CD

C. oz
z

x x cn

0
x x X Ix x x I -Z
t=l

TABLE 15-4 (cont'd)
LITERATURE STJJMMARY OF CHAEThCEROS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND TEMPORAL DISTRIBUTION

MONTHS
Species Locality Source J F M A M J J A S 0 N -D

C. ceratosporus Lower Bay 7 x

C. coarctatus Lower Bay 5 x

Lower Bay s x

Mouth of Bay 10 x
C. compressus Lower Bay 7 X IX IX X I X IX IX X X x
Lower Bay 9 x I I x Ix x x x x x x x
Lower Bay 6 Not avai abLe I
Lower Bay -s x x ix x Ix Ix x x
Calvert Cliffs s -X -X IX I IX X
Mouth of Bay 10 X X I x x x

C. concavicornis Lower Bay s x x x

Mouth of Bay 10 x x

C. constrictus Patuxent R. 8 RaVe I

Lower Bay 7 x x

Lower Bay 9
LE

TABLE 15-4 (cotit'd)
LITERATURE SUMMARY OF CHAETOtEROS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND TEMPORAL DISTRIBUTION

CD
-.40
m P. MONTHS
Species Locality Source J F @M A -M J J A S 0 N D
Ul C. convolutus Patuxent R. 8 Su=4 I I

Lower Bay 5 x x
Mouth of Bay 10 lx

C. curvisetus Lower Bay_ 7 x x x x x

Lower Bay 9 x

12 Not avai abLe

Mouth of Bay 10. x

C. d adayi Lower Bay 9 x
C. danicus Patuxent R. 8 R4e I I I I I I
Lower Bay 7 X. I I x I Ix x x x x
Lower Bay 9 x x IX. X. I x x x x x
Mouth of Bay 10 xIx x x
C. debilis Patuxent R. 8 Rare I
Lower Bay 9 1 X- x

Lower Bay 5 x
Mouth of Bay 10 L

TABLE 15-4 (cont'd)
LITERATURE SUMMARY OF CHAETOCER!bS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND TEMPORAL DISTRIBUTION

MONTHS
Species Locality Source- J F M A M J J A S 0 N D
C. decipiens Patuxent R. 8 4U4 I I I I

Lower Bay 7 x x x x x

Lower Bay 9 x x x x

Lower Bay 6 x

Lower Bay 5 x x x x x x x x
Calvert Cliffs 5 x I Ix x x x x
12 Nok aVailab@e I
Mouth of Bay 10 X IX IX I x Ix x
Calvert Cliffs to
mouth of Bay 11 N4 a@ailabLe
12

C. densus Lower Bay 7 x x
Lower Bay 5 1 it x x I x x
Calvert Cliffs @7 -X I Ix x x x
Mouth of Bay 10 x x I x x x
C. didymus Patuxent R. 8 4e I

Lower Bay 7 x x x
L @e

TABLE P5-4 (cont'd)
LITERAT17RE SUMMARY OF CHAETOCEROS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND TEMPORAL DISTRIBUTION

PA MONTHS
00
Sptcies Locality Sour ce J F M A M J J . A S 0 N D
C. didymus Lower Bay 9 x X. Ix x I x I
Lower Bay 5 1 x x x I x x
Mouth of Bay 10 X X IX x x x
C. eibenii Patuxent R.- 8 Rare I
Lower Bay 5 ix Ix x x x
Mouth of Bay 10 1 1 1 1 x ix x
C. filiformis Lower Bay 7 Ix I x I I
C. fragilis Lower Bay -9 x Ix
C. gracilis Patuxent R. 8 Spri4
Lower Bay 7 x x ix x x
C. laciniosus Lower Bay 9 x x I I
Lower Bay 5 Ix x x x I
Calvert Cliffs X IX

Mouth of Bay 10 x x x

C. lorenzianus Lower Bay 7 x x x x x x x x
Lower Bay 9 A -1 x x Ix I I I

A- i@,

TABLE,15-4 (cont'd)
LITERATURE SUMMARY OF CHAETOCEROS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND MTORAL DISTRIBUTION

MONTHS
Species Locality Source J F M A M J J. A S 0 N D
C. lorenzianus Lower Bay 5 ix I
Calvert Cliffs 5 x X IX
C. messanensis Mouth of Bay 10 x Ix
C. mitra. Mouth of Bay 10 ix
C. peruvianus Lower Bay 7 x Ix x X X X IX x x I x Ix
Lower Bay 9 X-jx x I x x x I X X IX
Lower Bay 6 Not 4ailabile I I I .-
Lower Bay 5 1 1 1x x I
Calvert Cliffs 5 X IX I X x Ix Ix x X X X
Mouth of Bay 10 X X I Ix I x x I
12 NoK availahle I
C. pseudocurvisetus Lower Bay 9 x X- I x
Mouth of Bay 10 Ix. x

x x
Lower Bay

C. gseudocrinitus Patuxent R. 8 Rare
x C. pendulus 12 Nc -4
@-j

TABLE,15-4 (cont'd)
LITERATURE SUMMARY OF CHAETOCEROS SPECIES IN CHESAPEAKE BAY
coo WITH SPATIAL AND TEMPORAL DISTRIBUTION
Op.
MONTHS
Species Locality Source J F -M A M -J J A -S 0 N D
Pooles Island to
C. pendulus mouth of Bay 11 No@ 4ai abLe I I I I

C. radicans Lower_Bay 5 x
Mouth of Bay 10 Ix x I
C. ralfsii 12 Not 4aila4e I I
C. rostratus Lower Bay 6 1x Ix Ix
'Mouth of Bay 10 1 1 x I I x x Ix
C. septentrionalis Patuxent R. 8 4e
Lower,Bay 7 x x x

C. similis Lower Bay 7 x x x x x

Lower Bay 9 x

Lower Bay S x

Calvert Cliffs 5 X X X

Mouth of Bay 10 x x

C. simplex Calvert Cliffs 5 x
C. socialis Patuxent R. 8 Autum@

ay x
Lower B T 7

TABLE 15-4 (cont'd)
LITERATURE SUMMARY OF CHAETOCEROS SPECIES IN CHESAPEAKE BAY
WITH SPATIAL AND TEMPORAL DISTRIBUTION

MONTHS
Species Locality Source J F M A M J J A S 0 N D

C. socialis Calvert Cliffs 5 x x x

C. subsecundis Lower Bay 9 x
C. subtilis- Patuxent R. 8 Rare- I
Lower Bay 7 x I X x X X x x
Low6r Bay 9 x Ix x x x x x x
Lower Bay 6 Not airaiLabke I
Lower Bay S x I x x x I
Calvert Cliffs S x x I x x x x
C. seiracanthus I Nolt a ai a4e
C. teres Patuxent R. 8 R@e I

Lower Bay 9 x
12 Nolt a ailable
Mouth of Bay 10 1 X-
v C. wighami Patuxent R. 8 R@e
00
@-j0 1 Njt a a-"e
01 v i ab

Cell wall formed of two valves and one or two girdle
bands. Two frequently unequally developed girdle bands
always piesent in most-species. Intercalary bands pres-
ent in some species, usually difficult to see without
special preparations.

Cytoplasm either forms a thin layer along the cell wall
or fills the greater part.of the cell. Nucleus against
the cell wall or central. Chromatophores vary greatly in
number, size, form, and position in different species;
may be one to several, small or large, but are constant
for a given species and consequently indispensable for
species demarcation. In many species, pyrenoids are
distinctly visible.

Resting spores formed in most neritic species. Only
one spore formed in a vegetative cell, usually in cylin-
drical part near the girdle band of the mother cell, in
some species near the cell end. Free ends.of spores
often armed with spines or spicules. Each spore with
two valves, but.only primary valve provided with a valve
mantle. Younger resting spores often-smooth. If spore
.lies near end of cell, one valve may be in common with
that of mother cell, with valve mantle rudimentary and
setae shorter and thicker than in vegetative cells.
Such spores always in pairs; formed in adjacent'cells
simultaneously.

Auxospores known in only a few species. Contents of
cell empty laterally and form a large globule or bladder
within which the new daughter cell is formed.

Microspores known in several species. Formed by repeated
divisions of nucleus and cytoplast. Contain organized
chromatophores. Locomotion observed in some species.

Great variations may be observed in chains of the same
species from different localities and at different times
of the year, Cupp (1943).

Ecology
Habitat (physical/chemical)
Salinity range: No entirely freshwater species known
(Cupp, 1943). Cosmopolitan distribution in oceans and
estuaries indicates tolerance of euryhaline conditions
at least for some species.
Temperature range: Variab16 within genus. Mulford
(1972) observed C. socialis as an autumn-winter species.
C. sub-tilis was -observed during the warmer months, and
U. affinis was observed from May to December.

Appendix 15
82

Importance

Size: Although Van Valkenburg and Flemer (In press) have
reported nannoplankton to be responsible for the bulk
of carbon fixation in the Bay, the genus Chaetoceros is
often reported as a dominant in the "net phytopl.-ainT-ton,"
(Mulford 1972; Mulford and Norcross 1971; Marshall
1967). Its contribution is therefore significant.
.4-
Bibliography

1. Griffith, Ruth E. 1961. Phytoplankton of Chesapeake Bay.
Contrib. No. 172,1 Chesapeake Biol. Lab., 79 p.

2. Cupp, Easter E. 1943. Marine plankton diatoms of the
west coast of North America. Univ. of Calif. Press,
237 p.
3. Mulford, Richard A. 1972. An annual plankton cycl@e on
the Chesapeake Bay in the vicinity of Calvert Cliffs,
Maryland, June 1969 - May 1970. Proc. of the Acad. of
Nat. Sci. of Phila.# 124(3):17-40.

4. Van Valkenburg, Shirley D., and D. A. Flemer. 1974. The
occurrence, abundance, distribution and production of
nannoplankton in a temperate estuarine area. (In
press.)

5. Mulford, Richard A.3. and J. J. Norcross. 1971. Species
composition and abundance of net phytoplankton in -
Virginian coastal waters, 1963-1964. Chesapeake Sci.
12(3):142-155.

6. Marshall, Har old G. 1967. Plankton in James River Estu-
ary, Virginia. I. Phytoplankton in Willoughby Bay and
Hampton Roads. Chesapeake Sci. 8(2):90-101.

7.. Patten, B. C.31 R. A. Mulford, and J. E. Warinner. 1963.
An annual phytoplankton cycle in the lower Chesapeake
Bay. Chesapeake Sci. 4(l):1-20.

8. Morse, Dorothy C. 1947. Some observations on seasonal
variations in plankton population, Patuxent River,
Maryland, 1943-1945. Chesapeake Biol. Lab., 65:31 p.
9. Mulford, Richard A. 1962. Diatoms from Virginia tidal
waters. Va. Inst. Mar. Spec. Sci. Rep. 30:1-33.

10. Mul ford, Richard A. 1964. Investigations of inner
Continental Shelf waters off lower Chesapeake Bay.
Part V. Seasonality of the diatom genus Chaetoceros.
Limnol. and Oceanog. 9(3):385-390.

Appendix 15
83

11. Whaley, R. C., and W. R. Taylor. 1968. A plankton
survey of the Chesapeake Bay using a continuous
underway sampling system. Chesapeake Bay Inst. Tech.
Rep. No. 36, 89 p.

12. Wolfe, J. J.* B. Cunningham, N. F. Wilkerson, and J. T.
Barnes. 1926. An investigation of the microplankton
of Chesapeake Bay. J. Elisha Mitchell Sci. Soc. 42:
25-54.

Appendix 15
@84

Category: Invertebrates

Common Name: Silver hydroid (edit. suggestion), "grass" by
watermen; "white weed" in England.

Inventory Prepared by: D. G. Cargo
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification:

Phylum: Cnidaria
Class: Hydrozoa
Order: Leptomedusae
Family: Sertulariidae
Species: Sertularia argentea L.

Distribution

Known range: Arctic Ocean t1o North Carolina and Louisiana
(Calderf 1971).

Distribution: Lower Bay and tributaries (Clark, 1882;
Fraser, 1944).

Occurrence.elsewhere: Extends into mid and upper Bay
areas (personal observation).

Population

'Abundance: Abundant on a variety of substrates, shells.,
rocks, crustaceans, annelid tubes, barnacle shells
(Calder, 1971).

Affecting factors: Temperature - annual

Reproduction:
Method: Separate cf and 9 colonies exist. Sexual breeding
in summer produces planulae. Hydroids 70 mm and larger
were able to breed.

Seasons: gonophores - Nov. to May (Calder, 1971)
gonangia - in summer, June-August (Hancock et al., 1956)
Fecundity: 1001'of colonies breed in peak@summer spawn-
ing (Hancock et al., 1956)

Life Stages

Early stages

Appendix 15
85

Early stages (Continued)

Physical features: Planulae .5 mm. long, blunt anterior
end (Hancock et al., 1956)

Development: Settled planulae reached polyp stage in 12
days. Growth: .3-1.3 mm/day in quite young colonies
in summer. .2-mm/day for older colonies in winter
(Hancock et al. , 1956).

Survival: Regeneration possible at,all levels in hydro-
thecae (Hancock et al., 1956)

Behavior: Planulae do not swim hear surface swim near
bottom. Swim 2-3 days.

Adult stage

Physical appearance: Calder (1971) gives an explicit
description: "Colony consisting of a monosiphonic
hydrocaulus reaching 35 cm or more high, branches
arising from all sides in a regular arrangement.
Branches dichotomous with a hydrotheca in each axil.
Hydrotheca sessileV alternate quite distant, fusiform,
being widest in the middle somewhat-less than half of
the adcauline wall; free, distal portion curved grad-
ually-outward, but hydrothecae facing upward. Oper-
culum of two valves, 2 prominent teeth, abcauline
caecum present. Gonophores fixed, gonothecae arising
from the upper surface of the branches near the base
of the hydrothecae; arrow shaped with one or two prom-
inent shoulder spines distally and a short collar
bordering the terminal opening.",

Survival: Temperature - regresses in summer, resurges
when temperature dro s to 200C and below from old
growth. Growth rapN (Calder, 1971).

Ecolo
a itat
Physical/chemical

Substrate: Sandy or shelly bottom

Salinity range: Meso-polyhaline (Wass, 1972).

Associated communities: Serpulid polychaetes, sand
dollars, sea urchins (Calder, 1971)

Food Requirements 4i

Food: Minute animal material-; protozoans, dinoflagellates,
planktonic organisms.

Appendix.15
86

Consumers

Natural predators: Hancock, et al (1956) observed Idulia
on Sertularia in England, but did not see it feedYng on
the hydroid. However, Browne (1907) observed Tergipes
grazing on Syncoryne.

Man: "White weed" industry prominent in Thames estuary
of England. Hydroid is processed and dyed to use decora-
tively, mainly in the United States. Fishery concentrated
in Thames estuary (Hancock, et al., 1956).

Non-nutritional Roles

Competition: Membranipora encrusts fronds. Other hydroids
may attach to it. M-1trichous ciliates are abundant on
it. Developing bivalve larvae find it a haven (Hancock
et al., 1956).

Protection: Furnishes cover and food-for gastropods and
crustacea.

Bibliography
Browne, E. T. 1907. A new method for growing hydroids in
small aquaria by means of a continuous current tube. J.
Mar. Biol. Assoc. U.K., 8:37-43.

Calder, D. R. 1971. Hydroids and hydromedusae of southern
Chesapeake Bay. Virginia Inst. Mar. Sci. Spec. Pap. in
Mar. Sci. #1, pp. 71-72; 125 p.

Clark., S. F. 1882. New and interesting hydroids from the
Chesapeake Bay. Mem. Bost. Soc. Natur. Hist. 3:135-142.
Fraser., t. M. 1944. Hydroids of the Atlantic Coast of North
America. Univ. of Toronto Press,, Toronto. 451 p. @

Hancock, D. A.3 R. E. Drinnan, and W. N. Harris. 1956.
Notes on the biology of Sertularia argentea L. J. Mar.
Biol. Soc. U.K. 35:307-3=.

Wass, M. L. 1972. A check list of the biota of lower
Chesapeake Bay. Virginia Inst., Mar. Sci. Spec. Sci. Rep.
#65, 290 p.

Appendix 15
-87

Category: Invertebrates

Common Name: Green anemone (editor)

Inventory Prepared by: Leo L. Minasian Jr.
Department of Biology
Florida State University
Tallahassee, Florida

Classification: Original description with subsequent revi-
sions accorffing to taxonomic review in Hand (1955).

Phylum: Cnidaria
Class: Anthozoa
Order: Actinaria
Suborder: Nynantheae
Tribe: Thenaria
Subtribe: Acontiaria
Family: Diadumenidae
Species: Diadumene leucolena (Verrill, 1866)

Distribution

Known range: Cape Cod Bay to Beaufort, N. C.; San Francisco
Bay area

Distribution: In Chesapeake Bay; generally abundant in the
poly- and mesohaline regions of the Chesapeake Bay,
extending from the mouth of the bay north to the Severn
River area, 'Salinity patterns permitting.

Population

Density: Population densities vary seasonally; peak
densities can be as high as 2000 individuals per square
meter (Minasian,.unpublished).

Dynamics

Trends and fluctuations: Peak settlement of these anem-
ones occurs during the summer in-the Patuxent River
estuary (Cory, 1967). Population abundance may peak
during the autumn months prior to a precipitious
decline in temperature (Minasian, unpublished).

Affecting factors: Population abundances are dependent
upon seasonal trends in temperature and salinity.

Reproduction
Method: Dioecious; fertilization is internal, although
external fertilization may also occur. Planulae are
sometimes visible within the maternal coelenteron

Appendix 15
88

Method (Continued)

.(Mecca, 1969). Asexual reproduction is by budding and
longitudinal fission, according to Mecca (1969).

Seasons: Sexual reproduction in the Chesapeake Bay
occurs during the summer months. If a group of anem-
ones is kept in the laboratory at this time, individual
females may release clutches of eggs, usually already
fertilized, within a day or two (Minasian 9 unpublished).
Cory's (1967) project also showed settlement of D.
leucolena larvae to be heaviest during the summeF
season.

Fecundity: Individual females may release several hundred
eggs.

Life Stages

Early stages: Eggs show cleavage patterns soon, if not
immediately, after being released. A coeloblastula.
results, which invaginates to form a gastrula. The
planula stage is reached in about two days. The plan-
ulae of this anemone swim actively by means of cilia,
and possess an obvious apical tuft of very long cilia
(flagella?) at the aboral end, which contacts the sub-
stratum in settlement. The planula has a well developed
stomodeum and gut, but is not known to feed during its
brief existence in the plankton.

Adult stage: Mature adults may vary in size, but large
individuals are 20 - 25 mm. in length, with a diameter
of 8 - 12 mm. When,expanded, the length of the column
may be four to six times its diameter (Hand, 1955).
Cinclides, holes in the body wall through which the
acontia are extruded, are present on the upper part
of the column. There are usually four to,six cycles
of tentacles, numbering over 200 in larger animals.
Individual tentacles are filiform, and as long as 2 cm.
Inner tentacles are longer than outer ones (Hand, 1955).
A single "catch tentacle", about 4 cm long, is present
on a few individuals. About 8% of the specimens of D.
leucolena at Solomons Is., Md. possess this catch teffta-
cle (MecEa, 1969). These anemones vary in color from a
vary pale pink to various shades of green. The green
color is due to the presence of a gastrodermal algal
endosymbiont.

During the winter months, these anemones are quiescent,
fully contracted, and covered by a secreted mucous film
and surface growth (Mecca, 1969). This dormant condition
is described as "encystment" by Sas'saman and Mangum
(1970).

Appendix 15
89

Ecology

Physical/,chemical

Classification: D. leucolena is a brackish-water forms
and is most abuFdant at estuarine salinities. It is
epifaunal, the most typical substrate being oyster
shells.

Salinity range: D. leucolena shows at least 50% survival
in salinities ringing from-6 - 33% (Pierce and Minasiank
.1974).
Temperat ure range: Sassaman and Mangum 0(1970) found that
exposure to a water temperature of 40 C for more than 2
hours is lethal for this species. At the opposite
extreme' D. leucolena withstands low water temperatures
near the -freezing poTnt.

Dissolved oxygen range: D. leucolena is sensitive to low
02 concentrations, whicS are lethaY in less than 24
hours. According to Sassaman and Mangum (1973), this
anemone consumes all available 02 in solution, and then
shuts down its 02 uptake when the environmental 02 con-
centration falls to 2 ppm. Beattie (1971) found no
metabolic adjustments in D. leucolena which could indi-
cate anaerobic function. -

Associated communities: This anemone is one of the primary
organisms which exists as part of the oyster (C. virginica)
community in the Chesapeake Bay.

Food Requirements

Food: D. leucolena is known to prey upon any organisms of
suita5le size, ringing from zooplankters to polychaetes.
.Thus., it is a consumer., showing several possible trophic
relationships.

Feeding: D. leucolena feeds in the typical manner of all
coelenteFate predat5'rs: by seizing the prey with special-
ized microscopic organelles called nematocysts. Nemato-
cysts entangle, adhere to, and puncture the prey tissues
while injecting a toxin. Subsequent tentacular movement
and ciliary currents function in ingestion. D. leucolena
has three different nematocyst t pes, with twFadditional',
different nematocyst types on th@ catch tentacle, if
present (Hand, 1955).

Consumers

Natural predators: The most probable predators of D.
leucolena are fish which graze on epifauna. of the-oyster

Appendix. 15.
.90

Natural predators (Continued)
community, and certain predaceous gastropods (e.g.
Epitoniidae, Pyramidellidae).

Non-nutritional Role

Competition: D. leucolena is'in competition for space with
certain otheF epitaunal species,, especially hydroids and
bryozoans.

Bibliography

Beattief C. W. 1971. Respiratory adjustments of an estuarine
coelenterate to abnormal levels of environmbntal phosphate
and oxygen. Comp. Biochem. Physiol. 40B:907-916.

Cory, R. L. 1967. Epifauna of the Patuxent River estuary,
Maryland, for 1963 and 1964. Chesapeake Sci. 8(2):71-89.

Hand., C. 1955. The sea anemones of central California.
Part III. The acontiarian anemones. Wasmann J. Biol.
13(2):1897251.

Mecca,, C. E. 1969. Disc electrophoretic studies on molecul-ar
adaptation under natural and artificial stress in the sea
anemone Diadumene leucolena (Verrill) and notes concerning
its natural histiTry. Ph.D.- thesis,, George Washington
University, 116 pp.

Pierce, S. K. and L. L. Minasian. 1974. Water balance of a
euryhaline sea anemone, Diadumene leucolena% Comp. Biochem.
Physiol. 47A: (in press-T-.

Sassaman, C. and C. P. Mangum. 1970 Patterns of temperature
adaptation in North American Atlantic coastal actinians.
Mar. Biol. 7(2):123-130.
Sassaman, C. and C. P. Mangum. 1973. Relationship between
aerobic and anaerobic metabolism in estuarine anemones.
Comp. Biochem. Physiol. 44A.-1313-1319.

Appendix 15
91

Category: Invertebrates

Common Names: Bloodwormp beakthroweri- bloods

Inventory Prepared by: Hayes T. Pf itzenmeyer
Natural Resources In'stitute
University of Maryland
Solomons, Maryland

Classification

Phylum: Annelida
Cl-ass: Polyqhaeta
Order: Eunicida
Family: Glyceridae
Species: Glycera dibranchiata Ehlers
Other species: 'G-. capitata, @j. amF-ricana,and G. robusta

Distribution

Known range: Gulf of St. Lawrence to Florida, Gulf of
Mexico (Florida, Texas);_central California to Lower
California and Mexico (Pettibone 1963).

Distribution in Chesapeake Bay: Probably-limited to saline
areas 13 to 15 o/oo. Species disappeared in mid-bay areas
after salinity decline as a result of hurricane in June
1972.

Population

Structure: Female to male ratio, 1.24:1 (Creaser 1973)
Density: Variable, 18-220/m2 (Wass 1972).

Dynamics

Trends and fluctuations: Very variable, may be long-term
or short-term, year to year fluctuations.

Affecting factors: Changes in physical characteristics
of mud flats in Canada. Populations in Chesapeake Bay
are very variable. Yearly fluctuations appear related
to changes in salinity pattern.

Reproduction

Method: Sexually mature worms, epitokes, emerge from
sediment and swim to water surface. Males emit sperm
from posterior end while swimming at surface. Body
wall of females ruptured near the posterior one third
of worm and eggs liberated. All worms probably die
after spawning. Remaining cuticle and atrophical
organs called "ghost worm."

Append ix 15
92

Reproduction (Continued)

seasons and conditions: Spawning begins in June at
13-140'C,, and is completed by August in Maine. -Began
2 hrs, before high water and continued during high
tide. Possibly two breeding seasons per year in
Maryland - June-July, and again in November-December
(Simpson 1962).

Fecundity: Worm 22-24 cm may contain 1.5-2.0 million
eggs (Canada), whereas in Maine--it would contain
3.0-3.5 million. Become sexually mature and spawn
as 3-yr olds (Klawe and Dickie 1957).

Life Stages

Early stages

Physical appearance: Swimming blastulae develop after
about 22 hrs, and at 32 hrs the trochlear ring is
formed. At this stage, the larvae alternate short
periods of rest on bottom with vigorous swimming.
Pelagic larvae soon elongate and the buccal aperature
becomes strongly ciliated (Klawe and Dickie 1957).

Development: Smallest specimens found in Canada were
3 cm long and suggest these were probably 1 yr of
age. Late larval and post larval stages were not
found. Three-yr olds are 21 to 29 cm, 4-yr olds
average 31 cm.

Survival: Changes in habitat, especially bottom types,
affect commercial abundance.

Behavior: Larvae believed not pelagic in all stages
since none were collected in plankton tows (Klawe
and Dickie 1957).

Adult stage

Physical appearance: Length up to 370 mm. Width up to
11 mm. Segments up to 300. Parapodia with'2 sharply
conical presetal lobes throughout the length of the
body. Two shorter, bluntly conical:postsetal lobes
in the anterior region, the upper being shorter and
rounded; the lower one longer and bluntly conical; in
the middle region the 2 postsetal lobes are both bluntly
conical, the upper one shorter than the lower one. In
,the posterior parapodia there may be a single rounded
postsetal lobe with a conical tip. Branchiae 2, digit-
iform to ligulate,, nonretractile; the upper one occurs
between the dorsal cirrus and notopodium; the lower one
occurs anterior to the ventral cirrus; they are thin

Appendix 15
93

Physical appearance (Continued)

walled and contractile, with a thin layer of spiral
muscle fibers. Proboscis with proboscidial organs
are similar., small., conical, flattened, with a central
core and surface marked with oblique furrows.(Pettibone
1963). Vascular system lacking, but have corpuscles
containing hemoglobin in the coelomic (body cavity)
fluid.

Development:- Mean lengths of potential male and female
spawners between 32 and 36 cm. (3-4 yrs) (Maine);
spawning worm length is 14-20 cm in Maryland.

Survival: Maximum age - 5 yrs in Maine. Growth appar-
ently does not occur during June to August.

Behavior: Perform lateral movement in sediments. Appar-
ently emerge from sediments only during period of
spawning activity.

Ecology
ffaitat (Physical/chemical)

Substrate: Typical flat consists of soft dark mud about
12,inches in deep over hard, dark gray, mud-sand mixture
(Canada).

Salinity range: Lower limit probably 10 o/oo

Temperature range: Summer temperatures probably critical
since no growth takes place.

Depth/pressure: Near high tide line on beac h to 100
fathoms.

Associated communities: Common in eelgrass communitie,s
(Wass 1972), and sand bottom communities.

Food Requirements: Organic detritus feeders. Rarely found
in cleart san y soils.

Consumers

Natural predators: Herring gulls and striped bass consume
large numbers when the worms are pelagic during spawning.

Man: Bait-worm industry in Maine and Canada. In 1954 and
1955 annual landings of 4 million worms were valued at
$40,000 to Canadian diggers. The 1970 production in
Maine amourited to 8080186 lbs, valed at $1,381,676.

.A-Dpendix :L5
94,

Bibliogr4p hy

Creaser, E. P., Jr. 1973. Reproduction of the bloodworm
(Glycera dibranchiata in the Sheepscot Estuary, Maine.
J. FISH. Res. Bd. Canada 30(2):161-166.

Klawe, W. L., and L M. Dickie. 1957. Biology of,the
bloodworm,' Glycer; dibranchiata Ehlers, and its relation
to the blooU-w-o-r-m-Tishery of the Maritime Provinces. Fish.
Res. Bd. Canadat Bull. 115, 37 p.

Pettibone, M. H. 1963. Marine polychaete worms of the New
England Region. I. Aphroditidae through Trochochaetidae.
U. S. Natl. Mus. Bull. 227, Pt. 1, pp 215-220. -

Simpson, M. 1962. Reproduction of the polychaete Glycera
dibranchiata at Solomons, Maryland. Biol. Bull. M(Z):
396-411.

Wass, M. L. 1972. A checklist of the biota of Lower
Chesapeake Bay. Virginia Inst. Mar. Sci. Spec. Sci.
Rept. 65, 290 p.

Ap9eifd:UC I-S
95

Category: Invertebrates

Common Name: Coot clam, dwarf surf clam

Inventory Prepared by: Hayes T. Pfitzenmeyer
Natural Resources Institute
University of.Maryland
Solomons, Maryland

Classification

Phylum: Mollusca
Class: Pelecypoda
Order: Eulamellibranchia
Family: Mactridae
Species: Mulinia lateralis (Say)

Distribution

Known range: Maine to northern Florida, south to Texas
and Mexico.

Distribution in Chesapeake Bay

Areas of greatest density: Upper meso- and polyhaline
(above 8 o/oo). Peak populations in silt areas but
low reservoir populations apparently in nearshore sand
(Wass, 1972).

Occurrence in other areas: Also found where salinity is
less than 8 0/66-but populations are temporary.

Population

Structure: Sex ratio 50:50; maximum longevity appear-'s to
be 2 years.

Densities: In Tangier Sound 221,000/sq. m. (Wass, 1972)

Dynamics

Trends and fluctuations: Opportunistic species.with
highly variable densities.
Affecting factors: Ubiquitous set in sand and mud sedi-
ments of Pamlico River but adverse dissolved oxygen'
levels prevented permanent establishment in mud (Tenore,
1970).

Reproduction

Method: Sexes separate, eggs and sperm expelled into
water mass where fertilization takes place at 16.to 200C.

Appe@nffix- is
96

Behavior: Sirce it is a shallow burrowing @lecies, it is
subject to iqind-wave acti-ii which.oftenti-., -, washes tre-
mendous ni.,:-')ers in windrc along beaches.

Ecology
Habitat (Physical/chemical)

Substrate: Prebably preferE ind bottom! ut large
numbers may be found in s.i1i./clay sedii ts.

Salinity range: Usually o/oo I-tu been found
as low as 5 o/oo.

Temperature range: No sig,,'@[j :L M,.: lity at 21 to
270C in early developmeni L Lages; 0' of sensitive
'cleavage stages would be @-Iititinated iii 4 min. in water
at 26 to 380C (Kennedy etal.,, 1974).

pH range: 7.25 to 8.25 (CaJabrese and Da, s, 1970).

Dissolved oxygen range: Tolerances unknown but mass mor-
talities in channel areas aLtributed t(-) summer oxygen
deficiencies.

Food Requirements

Food: A primary consumer whicli probably fc@-Is on phyto-
plankton and detrital matter,

.Feeding: Filter feeder which extends its slilhon to water-
sediment interface and pumps large quanti;ies of water
from which it extracts its food..

Consumers

Natural predators and parasiv Highly in.!',--sted with
digenetic trematode cercari,4 iid metacercaria-P Cercaria
imbecilla and granosa (Gymnol.;-,illinae) flulliman (1961).
Provides .food T-o-F-f-is-h. stari_k@;11, oyster LOills, and
waterfowl (Calabrese, 1970).

Man: No direct value to man

Influence of Toxic Substances

Thermal shock: LC50 between 30 and 330C for specimens
acclimated between 2 and 250C (Kennedy, 1971).
Other toxins: No information available in published
literature on the influence of toxic substances. How-
evert Pfitzenmeyer (1971) did not find Mulinia in a
biological study of Baltimore Harbor, wH-ereas they were
abundant-in the Chester River. It is believed that this
species is sensitive to man-induced pollutants.

Appendix 15
97

Bibliography

,Abbott, R. T. 1954. American seashells. D. van Nostrand
Company. New York. 541 p.
Andrews, J. 1971. Seashells of the Texas Coast. Elma Dill
Russell Spencer Found. Series.No. 5, Univ. Tex. Press.
298 p.

Calabrese, A. 1969. Individual and combined effects of
salinity and temperature on embryos and larvae of the coot
clam, Mulinia lateralis (Say). Biol. Bull. 137(3):417-428.

1969. Mulinia lateralis: molluscan fruitfly?
Proc. Nati. Shellf. Assoc. 59:65-66.

1970. Reproductive cycle of the coot clam,
Mulinia lateralis (Say), in Long Island Sound. The Veliger
5 - 2 6 9.

'and H. C. Davis. 1970. Tolerances and require-
ments ot emDryos and larvae of bivalve Mollusca. Helgo-
lander. Wiss. Meeresunters 20, 553-564.

Chanley, P., and J. D. Andrews. 1971. Aids for identification
of bivalve larvae of Virginia. Malacologia 11(l);45-119.

Hollimant R. B. 1961. Larval trematodes from Apalachee Bay
area, Florida# with a checklist of known marine Cercaria
arranged in a key to their superfamilies. Tulan-F-9=7in
Zool. 9(l):1-74.

Kennedy, V. S., and J. A. Mihursky. 1971. Upper temperature
tolerances of some estuarine bivalves. Chesapeake Sci. 12.
(4):193-204.

Pfitzenmeyer, H. T. 1971. B. Benthos. In: A biological
study of Baltimore Harbor. Unpubl. Final Rept. to Maryland
Dept. Water Resources, University of Maryland, Natural
Resources Inst. Ref. No. 71-76, p. 20-49.

Tenore, K. R. 1970. The macrobenthos of the Pamlico River
estuary, North Carolina. Water Resources Res. Inst., Univ.
of North Carolina. Rept. No. 40, 113 p.

Wass., M. L. et al. 1972. A checklist of,the biota of lower
Chesapeake Bay. Virginia Inst. Mar. Sci. Spec. Sci. Rept.
No. 65, 290-p.

9PFPeft-d1x -15-
98

Category: Invertebrates

Common Name: Brackish-water clam (other proposed names have
Bee-n---m-a-rs'n clam, Gulf clam and wedge clam - editor).
Inventory Prepared by: Hayes T. Pfitzenmeyei
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification,

Phylum: Mollusca
Class: Pelecypoda
Order: Eulamellibranchia
Family: Mactridae
Species: Rangia cuneata Gray

Distribution

Known range: Pleistocene - New Jersey to northern South
America; recent - Maryland to Mexico.

Distribution in Chesapeake Bay

Greatest density: Areas of most dense populations were
first found in upper Potomac River in 1964 (Pfitzenmeyer
and Drobeck). Large specimens taken in oligohaline part
of James River in 1963; introduced in Rappahannock River
later.

Occurrence elsewhere: Small populations are found in.most
major tributaries of Chesapeake Bay. Since low salinity
conditions associated with storm AGNES in June 1972 were
correlated with spawning season, populations may be
found over a wide area. No established populations
found in Patuxent or York rivers.

Population

Structure: Populations quite often made up of single year-
class. Healthy populations should include several-year-
classes.

North Carolina and Maryland. (Average lengths).
1 yr. - 15 mm, 2 yrs. - 30 mm, 3 yrs..- 40 mm, 4 yrs. 45
mms, 5 yrs. 50 mm (Wolfe' and Petteway, 1968). -
Louisiana 1 yr. - 15 mm, 2 yrs. - 20 mm, 3'yrs. - 24 mm.,
Texas - 1 yr. - 19 mm, 2 yrs. - 31 mm., 3 yrs. 41 mm, 4
y
rs. - 48 mm, 5 yrs. - 51 mm.
Clams 5 to 7--year- old are. up to 63-64 mm in length.

Appendix 15-
99

Reproduction (Continued)

Seasons and conditions: Spawning completed by end of
Sept. or early Oct. in Long Island Sound. Some ripe
clams found at all seasons, but gametogenesis most
active mid-July through August (Calabrese, 1970).
Shaw (1965) reported setting throughout summer (May
to Nov.) in Maryland. Fall set in Pamlico River
(Tenore, 1970).

Fecundity: Three to 4-million eggs produced at one
spawning.

Life Stages

Early stages

Physical appearance: Larvae usually slightly pale or
light. No apical flagellum or pigmented eyespots.
Hinge undifferentiated except for faint irregularity
at either end. Posterior ligament appears at about
200 u. Rounded umbos at 80-100 u; becoming higher
and angular at 130-160 u; anterior end longer,
slightly more pointed than posterior. Metamorphosis
from 185 to 240 u (Chanley and Andrews, 1971).

Development: Larvae grew satisfactorily within salinity
range from 20 to 30 or 32.5 o/oo; 25 o/oo optimum.
Temperature range of satisfactory growth was from 20
to 30OC; 27.50C optimum (Calabrese, 1969).

Survival: Maximum development of fertilized eggs to.
straight hinge larvae and maximum growth of larvae
occur at 20 and 270C, respectively (Calabrese, 1969).

Adult stage

Physical appearance: Up to 20 mm in shell length. Beaks
quite prominent and near the center of the shell and
point'ing toward each other. Exterior whitish to cream
and smoothish except for a fairly distinct, radial ridge
near the posterior end (Abbott, 1954).

Developm ent: Life-span appears to be about 2 years.
Overcrowding probably affects growth rate. Generation
period approximately 60 days (Calabrese, 1969).

Survival: Large numbers of set can be found in soft
bottoms of deep water (>25 ft) of Chesapeake Bay.
These usually-die-off following summer during oxygen
dep!,@tion in these deep areas. Trematodes in various
stages must have some effect since infections up to
100% have been observed.

Appendix-15
100

Population (Continued)

Densities: Variable
; maximum reported in upper Chesapeake
Bay averaged 1,200 m2. This was single year-class aver-
aging 23 mm in shell length. Multi-aged populations
average up to 600/m2. Maximum length about S2 mm.

Dynamics.

Trends and fluctuations: Spawning and setting not
successful every year due to adverse environmental
conditions. Prolonged salinities near 0 or above
15 o/oo are also detrimental. Winter kill is also.
a factor in northern range.

Affecting factors: Adult populations made up of single
age-classes may be found in areas where salinities are
between I and 15 6/oo. These may not all be breeding
populations but were set and survived during periods
when conditions were more optimal. A change in salin-
ity, either up from near 0 or down from 15 o/oo is
necessary to induce spawning (Cain, 1972).

Reproduction

Method: Sexes separate. Eggs and sperm expelled into
water where fertilization takes place. Eggs 69 microns
in diameter'. Develop into veligers in 24 hrs., 75 to
130 microns long (Chanley, 1965).

Seasons and-conditions: Spawning takes place in summer
months when ambient temperature probably above 220C.-
Spawning can be induced artificially by raising temper-
ature a few degrees and/or raising the salinity up from
near 1 o/oo or down from near 15 o/oo.

Fecundity: James River clams in 14-20 mm length group
(1-yr.) had recognizable sex products (Cain, 1972).
Adult.may produce 1 to 3 million eggs.

Life Stages

Early stages

Physical appearance: Hinge teeth lacking; umb-o round,
inconspicuous. Straight-hinge line 55-60 u long.
Height S-10 u less than length. Umbo develops at
120-130 u. Larvae dark yellow, with a conspicuous
apical.flagellum. in all pelagic stages. Larvae develop
a foot and metamorphose at 160-175 u (Chanley, 1965).
Set wider (20-30 u less than length) than all other
species (Cain, 1972).

Appendix 15
101

Early stages (Continued)

Development: Straight-hinge larvae stage is reached after
24 hours (75-175 u). Set occurs after 6 to 7 days as
veliger larva (ave. 300 u). Rangia set are tolerant to
temperature and salinity chani-esand grow at same rate
up to 41 days (Hopkins et a!., 1973).

Survival: Embryos and early larvae can survive best in
salinities between 5 and 10 o/oo, and 20, 25, and 300C
(Cain, 1972).

Behavior: Recruitment of clams into marginal non-repro-
ductive areas is by selective swimming or by passive
,transport of larvae in a water mass.

Adult stage

Physical appearance: Shell highly variable in size, 20
mm in length and depth to about 70 mm in length and 60
mm. in depth, obliquely ovate, very thick and heavy.
Exterior whitish but covered with a strong, smoothish,
gray-brown periostracum. Interior glossy, white and
with blue-gray tinge. Pallial sinus small, but moder-
ately deep and distinct (Abbott, 1964).

Development: Maximum length of about 74 mm reached in
approximately 10 years (Wolfe and Petteway, 1968).
Largest size attained in lower salinities. Sand is
more favorable substrate than clay'-silt. High phos-
phate and high organic concentrations gave greater
growth in sand (Tenore et al., 1968).

Survival: High densities of single year-classes often
found. Howeverf mass mortalities often occur as pop-
ulation exceeds food supply or encounters adverse
seasonal factors.

Behavior: Natural position in bottom is with anterior-
end pointing downward, siphon-end vertical with its
tip just above sediment surface so umbones, lunule,
and most of shell buried. No lateral movement, only
vertical in sediment for purposes of'burial (Fairbanks,
1963).

Ecology
Habit-at (Physical/chemical)

Substrate: Greatest percentage found in sand, clay, and
silt, in that order. High concentrations of organic
matter and phosphates beneficial in sand but harmful
in silt-clay (Tenore et al., 1968).

Appendix 15
102

Salinity range: 1 o/oo to 15 0/00, mainly oligohaline

Temperature range: 0.5 - 31.30C - Maryland
2 - 400C - Louisiana
4 - 350C - Texas
30 - 350C is. critical range

Dissolved oxygen range: Consumption highest at 5 and 10
o/oo (Hopkins, 1973). Found in 5.36 to 13.22 mg/1
(Cain, 1972).

Benthic composition:
Scolecolepides viridis Brachidontes recurvus
Cyathura poTi-ta- Congeria leuc-opN-aeta
Corophiu@m_I_acustre CIFIronomid larvae
U-ammarus sp. Leptocheirus Plumulosus
R-acoma mitchelli Re-reis succ!'n-ea

Turbidity/light: Commonly found in highly turbid
environment.

Fluctuations effects: Short-term changes in salinity as a
result of increases or decreases in freshwater inflow
determine the success of recruitment.

Associated communities: Occupies the low salinity brackish-
water zone which overlaps the typical freshwater community
upstream and slightly overlaps the oyster bar community
towards the seaward border (Hopkins et al., 1973).

Food Requirements

Food: A filter-feeder which also utilizes detritus. Lar-
vae grow well on mixture of unicellular algae, probably
Isochrysis and Monochrysis (Chanley, 1965). Dunaliella
peircei used as-To-od in controlled experiments.

Consumers

Natural predators and parasites: Food for fishes, shrimps,
crabs, and waterfowl. Trematode sporocysts and cercaria
in gonads (Fairbanks, 1963), probably Fellodistom-la-t-M-e
and Bucephalidae.

Man: Shells utilized in place of gravel for-roadbeds
.(Gooch, 1971). Also calcium carbonate in manufacturing
of water purification apparatus. Meat used for food in
North Carolina (Hopkins et al., 1973).
Influence of Toxins

Heavy metals: Mercury, copper, and chromium are toxic to
Rangia at all salinities. Copper was most toxic ion in

Appendix 15
103

Heavy metals (Continued)

freshwater and chromium a close second (Olson and Harreli,
1973).

Radionuclides: Concentrations of caesium-137 variable
depending on rainfall'and amount of potassium in water
(Wolfe, 1967).

Bibliography

Abbott, R. T. 1954. American Seashells. D. van Nostrand
Co., New York., 541 p.

Cain, T. D. 1972. The reproductive cycle and larval toler-
ances of Rangia cuneata in the James River, Virginia. Ph.D.
Dissertat-l-on-.--Dept. of Marine Science, Univ. of Va. 120 p.

Chanley, P. 1965. Larval development of the brackish-water
mactrid clam, Rangia cuneata. Chesapeake Sci. 6(4):209-213.

Fairbanks, L. D. 1963. Biodemographic studies of the clam,
Rangia cuneata Gray. Tulane Stud. Zool. 10:3-47.

Gooch, D. M. 1971. A study of Rangia cuneata Gray in
Vermilion Bay, Louisiana. M.S. Thesi-s-7--UnFiv. Southwestern
Louisiana, 61 p.

Hopkins, S. H., J. W. Anderson, and K. Horvath. 1973. The
brackish-water clam, Rangia cuneata, as indicator of eco-
logical effects of salinity -cYa-nges in coastal waters.
Contract Rept. H-73-1, U. S. Army Corps of Engineers.
Texas A & M Univ., Dept. of Biology, 250 p.

Olson, K. R.P and R. C. Harrel. 1973. Effect of salinity on
acute toxicity of mercury, copper, and chromium for Rangia
cuneata (Pelecypoda Mactridae). Univ. of Texas. Con_t_r_F6-.
i
'W-
n arine Science 17:9-13.

Pfitzenmeyer, H. T'., and K. G. Drobeck. 1964. The occurrence
of the brackish-water clam, Rangia cuneata, in the Potomac
River, Maryland. Chesapeake S-cl. STTT=.-215.

Tenore, K. R. et al. 1968. Effects of bottom substrate on
the brackish-water bivalve Rangia cuneata. Chesapeake Sci.
9(4):238-248.

.Wolfe., D. A. 1967. Seasonal variation of caesium-137 from
fall-out in a clam, Rangia cuneata Gray. Nature 215(5107):
1270-1271.

V and E. N. Petteway. 1968. Growth of Rangia cuneata
_-G-r-ay. Chesapeake.Sci. 9(2):99-102.

Appendix 15
104

Category: Invertebrates

Common Name: Copepod

Inventory Prepared by_: Rogers Huff
Natural Resources Institute
University of Maryland
SolomonsP Maryland
,47
Classification

Phylum: Arthropoda
Class: Crustacea
Order: Copepoda
Suborder: Calanoida
Family: Temoridae
Species: Eurytemora affinis (Poppe, 1880)

Distribution

Known range: Northern Hemisphere. Coastal and estuarine
waters of Eastexn North America from the Gulf of St.
Lawrence to the Florida Keys; the Baltic, North, and
Caspian Seas, freshwater lakes in Central Asia and
Eastern North America, and rivers and estuaries of the
Gulf of Mexico.

Distribution in Chesapeake Bay: Entire Bay into fresh-
water tributaries. Present year-round in upper regions
of brackish tributaries. In higher salinities (up to
20 o/oo) it occurs in significant numbers from January
to May.

Population

Structure: Adult population usually predominantly male;
up to S:1 ratio. Age-group structure changes from over-
wintering adults and copepodites to predominantly nau-
pliar stages in the late spring and summer.
Denities: Density ranges from 1,000 up to 3 x 106 per
M . with highest populations recorded in sediment trap
regions during March and April.

Dynamics: Numbers highest in late winter and early spring.
Highest densities in tributaries and upper Bay.

Trends and fluctuations: Large, high-salinity winter
population in years when Acartia clausi-populations
"Ok are low. Spring population peaTs in low salinity
succeeded rapidly with emergence of Acartia tonsa.
Controlling factors are probably comFe't1tjon-`w`j-tff,
and possible predation by, Acartia spp., and predation
by finfish and Neomysis american-ain the spring months.

Appendix 15
105

Reproduction

Method: Reproduction sexual. Male attaces spermato-
phore to urosome of female. Female carries eggs in a
clutch until they hatch. Female requires fertilization
before each clutch of eggs.

Seasons and conditions: Capable of reproduction from 2
to 260C and at salinities ranging from 0 to35 0/00.

Fecundity: Egg clutches vary from 10 to over 100 eggs.
Egg development time ranges from 12.5 days at 50C to 1
day at 250C. New clutch of eggs is immediately ready
to be laid upon hatching or release of the previous
clutch.

Life Stages
Stages of life cycle: Life stages 13, egg, six naupliar,
and six copepodite. The final copepodite is the adult.

Early stages
Physical appearance: See Davis (1943)-Larvel stages
of the calanoid copepod Eurytemora hirundoides.
Nauploiar stage: Usual calanoid form. Approximately
2:1 length'width ratio. Living nauplii nearly
colorless except for blue-red eye spot. Preserved
specimens usually opaque. Distinguised by unequal
development of caudal spines in stages II through
VI. S ize mm (Stage VI).

Copepodite stage: Division into cephalosome, metasome,
and urosome; by Stage IV. lenght .475 mm to 1.275 mm to
1.275 mm (Stage V female).

Development: Duration of develoopmental stages equal at
constant temperature. Stage I nauplius molts to Stage
II within six hours at 20 C. Growth rates (days per
stage) range from approximately 6 days at 5 C to 1 day
at 25oC. Length and lenght-weight relation is dependent
on food concentration.

Suvival: Assumed to be nearly 100% in the absence of
predation.

Behavior: Nauplii hatched free-seimming and independent
of mother. Feeding begins with the development of mouth
in the Stage II nauplii. Vertical migration data
unavailable.

Appendix 15
106

Adult stage (see Davis, 1943)

Physical appearance: Male 1.4-1.65 mm. Females 1.5-1.8
mm. Female with nine segments; male eleven. Adult has
two sets of antennae, mandible, two sets of maxillae,
maxilliped, four pairs of swimming legs, and sexually
dimorphic-fifth legs. Right first antennae modified
for grasping in the male. Fifth legs asymmetrical and
longer in the male. Fifth thoracic segment modified
into pointed "wings" in the female and the first uro-
somal segment (genital) is swollen on the female.

Development: Little or no growth as adult. Animals
maturing at higher rate due to higher temperature are
smaller and of lower weight at all stages.

Survival: Mean survival time at 20C over 3 months for
females, 80 days for males. Decreases with increasing
temperature. At 23.50C adults live for 10-16 days.
Mortality largely due to predation.

Behavior: Swim by several different techniques, using
swimming legs, antennae and urosome for propulsion.
Considered planktonic, but adults, particularly fe-
males., may be concentrated,-clinging to litter and
aquatic plants on the bottom. This behavior may
partially account for the preponderance of males in
plankton tows.

Ecology
Habitat
PRy-sical/chemical habitat

Classification: Planktonic, true estuarine species.

Salinity range: Tolerates 0-35 o/oo.
Temperature range: Tolerates 1-300C.

Dissolved oxygen range: Resistant to very low dis-
solved oxygen concentrations--as low as .04 ug/l.

Turbidity/light: Occurs under lighted and turbid
conditions.

Depth/pressure: Essentially a shallow water species,
but occurs at all depths in the Chesapeake Bay.

Effects of fluctuations: Range expands seaward with
lowered salinity/temperature in winter and retreats
with increasing temperature 4nd salinity in spring.
Reproduces most successfully at 5-15 o/oo salinity
and up to 200C. Growth rate higher than Acartia tonsa
below 12-150C.

Appendix 15.
107

Food Requirements

Food: Herbivorous, grazing on phytoplankton. Large early
spring blooms could not be supported by the existing
phytoplankton populations. Animals are therefore acting
as detritovores or feeding on protozoan and bacterial
communities associated with detritus. Utilizes particles
from 2-63 um. Feeding efficiency lower than in marine
copepods.

Feeding: Probably feeds continuously throughout the day on
an intermittent basis. Filter-feeder, selective in it,s
ingestion. Filtering rates and selectiviiy under study.

Consumers

Natural predators and parasites: Consumed by larval stages
of most estuarine fish and by adult zooplankters,both
filter and individually selective feeders, including cten-
ophores, medusae, and many other invertebrates. Quantita-
tive data on predation does not exist. Parasites include
Zoothamnium and other protozoans.

Non-nutritional Role

Competition: Competes with other estuarine filter-feeding
herbivores and detritovores.

Non-nutritional Role of Other Species

Competition: Other filter feeders compete.

Protection: In presence of Acartia tonsa and predators,
Eurytemora concentrates on the bo Tom-, using vegetation
or litter tor protection.

Influence of Toxic Substances

Biocides: Pesticides under study, also effects of chlorine
in secondarily-treated sewage.
Thermal shock: Exposure to a temperature of 300C for 24
hrs killed all animals acclimated at 250C Eurytemora
adults acclimated at lower temperatures, i. ID9 15, and
200C, showed higher tolerance for thermal shock, with
maximum survival at 10-150C.

Bibliography
Burrell., V. J.V Jr. 1972. Distribution and abundance of
calanoid copepods in the York River estuary, Virginia,
1968 and 1969. Ph.D. dissertation, School of Marine
Science, College of William and Mary.

.Appendix 15
108

Davis, C. C. 1943. The larval stages of the calanoid copepod
Eurytemora hirundoides (Nordquist). Maryland Bd. of Nat..
Pub. No. S8.

Heinle, D. R. 1969. Temperature and zooplankton. Chesapeake
Sci. 10:186-209.

Heinle, D. R. 1970. Population dynamics of exploited cul-
tures of calanoid copepods. Helgolander wiss. Meersunters.
20:360-372.

Heinle, D. R., Flemer, D. A., Ustach, J. F., Murtagh, R. A.V
and Harris, R. P. 1973. The role of organic debris and
associated micro-organisms in pelagic estuarine food chains.
Univ. of Maryland Nat. Res. Research Ctr. Tech. Rept. 22.

Jeffries, H. P. 1962. Copepod indicator species in estu-
aries. Ecology 43:730-733.

Jeffries, H. P. 1962. Salinity-space distirbution of the
estuarine copepod genus Eurytemora. Intern. Rev. Hydrobiol.
47:291-300.

Jeffries., H. P. 1967. Saturation of estuarine zooplankton
by congeneric associates. Pages 500-508 in George H. Lauff,
ed. Estuaries, Am. Assoc. Adv. Sci.

Katona, S. K. 1970. Growth characteristics of the copepods
Eurytemora affinis and E. herdmani in laboratory cultures.
Helgolan -il-s-s. MeersiTnters. 20:373-384.

Katona, S. K. 1971. Ecological studies on some planktonic
marine copepods. Ph.D. thesis, Harvard Univ., 146 pp.

Katona, S. K. 1973. Evidence for sex pheromones in plank-
tonic copepods. Limnol. Oceanogr. 18:574-583.

Wilson, C. B. 1932. The copepods of the Woods Hole region,
Massachusetts. U. S. Nat. Mus. Bull. 158:110-112.

Appendix 15
1 109

CategorX: Invertebrates
Common Name: Grass, or glass, shrimp (collectively with
others of this genus)

Inventory Prepared by: D. G. Cargo
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification

Phylum: Arthropoda
Class: Crustacea
Order: Decapoda
Family: Palaemonidae
Species: Palaemonetes pugio (often confused with P.
intermedius where ranges overlap.

Distribution

Known range: Massachusetts to Port Aransas, Texas
(Williams 1965)

Distribution in Chesapeake Bay: Bay-wide, especially in
vegetation.

Population

Structure: Sexes even, life span annual.

Density: Abundant in quiet, weedy areas.

Affecting factors: Abundance of vegetation, especially
Zostera and Ruppia.

Reproduction

Method: Sexual by copulation, eggs carried by female.

.Seasons: May through September
Fecundity: '200-300 personal estimate

Life Stages

Stages of life cycle: Zoea, post larvae, adult

Early stages:
Physical appearance: Elongate zoea unarmored except for
rostrum. Prezoeal molt occurs prior to hatching.
Approx. 2.6 mm. long. Abdomen of 6 somItes, telson with

Appendix 15
110

Early stages (Continued)

Physical appearance (continued)

16 spines. Nine more zoeal stages. Tenth 6.3 mm; post
larval 6.3 mm. Similar to P. vulgaris in many respects.
Abdominal somite 2 has a paTr of chroFafophores, lacking
in vulgaris (Broad 1957a, 1957b).

Development: Developmental rates variable, depending on
larval diet (Broad 1957a).

Survival: With no food or unicellular algae, 2 molts -
100% mortality. Survival past 7 molts with Artemia
nauplii, <20% mortality (Broad 1957b).

Behavior: Very seasonal in Chesapeake Bay. Young
numerous in late spring.

Adult stage

Physical appearance: Lobster like, small chelae on lst
and 2nd walking legs.

Development: With adequate diet, 7th inter-molt yielded
post larvae at,18 days after hatch (Broad 1957b).

Behavior: Adults abundant in late summer, especially in
beds of vegetation; hibernation appears to be initiated
at about 100C.

Eco logy
Habl-tat (Physical /chemical)

Substrate: Estuarine - weedy areas.
Salinity range: Oligo-polyhaline (Wass 1972). 5.4 o/oo
to approx. 30 o/oo.
Temperature range: 30-300Chibernates at 100C and below.

PH range: 7-8.5

Benthic composition: Weeds, muddy sand

Effects of fluctuations: Presence or absence of weed beds
appears to have a major effect upon local abundance.

Associated communities: Shallow Zostera and Ruppia.

Food Requirements
Plant and animal., scavenges@, -bats detritusalgae and
plant food alone is inadequate (Bro-ad 1957b).

Appendix 15

Consumers

Natural predators and parasites: Fish and jellyfish, para-
sitized by Probopyrus@pandalicola.

Man: Small local fisheries in Chesapeake Bay for sport
fish bait in recent past; minor use now.

Non-nutritional Role

Protection: Rostrum, telson spines and armored periopods.

Influence of Toxins

Biocides: Probably very susceptible to insecticides.

Heavy metals: Cadmium chloride (0.42 mg/1), lethal to 50%
of P. vulgaris (Eisler, 1971).
Thermal shock: LD50-(24 hr)-32-37.50C depending on acclima-
tion temp. (Mihursky, et al.., 1971).
Bibli2graphy
Broad, A. C. 1957a. Larval development of'Palaemonetes pugio
Holthuis. Biol. Bull. 112(2):144-161.

. 1957b. The relationship between diet and larval
develo@m_ent of Palaemonetes. Biol. Bull. 112(2):162-170-.

Eisler., R. 1971. Cadmium poisoning in Fundulus heteroclitus
and other marine organisms. J. Fish. Res. Bd. Can. 28(g):
1225-1234.

Faxon., W. A. 1879. On the development of Palaemonetes
vulgaris. Bull. Mus. Comp. Zool. Harvard. 5:303

Mihursky, J. A., J. Gatz, D. R. Heinle, V. S. Kennedy, A. J.
McErlean, R. P. Morgan, and W. H. Rosenburg. 1971. Effects
of thermal pollution on productivity and stability of estu-
arine communities. Comp. Rep. Nat. Res. Inst. Office of
Water Resources Research) May 1965-June 1969. 65 p.

Wass, M. L. 1972. A check list of the biota of lower
Chesapeake Bay. Spec. Sci. Rep. No. 65. V.I.M.S.,
Gloucester Pt., Va. 90 p.,

Williams., A. B. 1965. Marine decapod crustaceans of the
Carolinas. Fish. Bull. U.S.D.I., FWLS. 65(l):59-61.

Appendix 15
112

Category: Invertebrates

Common Name: Sand shrimp, salt and pepper shrimp

Inventory Prepared by: David G. Cargo
Natural Resources Institute
University of Maryland
Solomons, Maryland
Y-

Classification

Phylum: Arthropoda
Class: Crustacea
Order:, Decapoda
Family: Crangonidae
Species: Crangon septemspinosa (Say), Crago septemspinosus
(old name) was changed by Holthuis, 1951.

Distribution

Known range: Baffin Bay to eastern Florida, Alaska and
Japan (Whiteley, 1948).

Distribution in Chesapeake Bay

Areas of active reproduction: Tributaries and Bay proper
from Swan Pt. to outside Bay mouth; more abundant in
lower Bay (Wass, 1972); 4.0-31.5 o/oo.

Occurrence in other areas: Farthest upriver in summer

Population

Structure: Sexes even; spawn at 1 year (Whiteley, 1948;
.Price, 1962); may live to age 3.

Dynamics

Trends and fluctuations: Size varies - seasonally

Reproduction

Method: Sexual

Seasons: Ovigers found at all seasons; in deeper waters
in winter. Most abundant in summer (Price, 1962).

Fecundity: At 70 mm. length, 3-4 thousand eggs/seison.

Life Stages

Early life stages

Appendix.15
113

Early life stages (Continued)

Physical appearance: At least 2 zoeal stages, reaches
2nd zoeal stage at 5 days after hatching.
Development: Hatching time 6-7 days at 210C, 30 days at
160C and 90 days at SOC

Adult stage

Physical appearance: Lobster-like, no chelae

Development: Time of hatching and embryonic development
controlled by temperature.

Survival: Boreal, not present in N. C. in summer.

Behavior: Surface swarming of juveniles has been observed
in spring (Solomons, 1974, Cargo).

Ecology
Ha5TJtat (Physical/chemical)

Substrate: Marine to mesohaline - sandy bottoms and
hydroids, not confined to benthos.

Salinity range: 4-31.5 o/oo
Temperature range: 0-260C

Depth/pressure: Shoal to 1801

Food Requirements

Food: Detritus, crustaceans, molluscs, invertebrate eggs,
also scavengers.

Consumers

Natural predators and parasites: Fish, skates (E!jLa) and
rays (Price,.1962), (Fitz, 1956).

Non-nutritional Role

Competition: Probably competes with xanthid crabs, por-
tunid crabs and other decapods for living space and food.

Influence of Toxins

Biocides

Chlorinated/hydrocarbons: Very susceptible to malathion
and methoxychlor in amounts of 33-83 ppb (Eisler &
Weinstein, 1967).

Appendix 15

Heavy metals: Sensitive to cadmium and mercury at .32 mg/1
much more so after long exposure.

Thermal shock: More sensitive than other local decapods
to high temps.,31C max. even under high temperature
acclimation (Mihursky et al., 1971).

Bibliography

Cowles, R. P. 1930. A biological study of the offshore
waters of the Chesapeake Bay. U. S. Bur. of Fish. Vol.
46:277-381.

Eisler., R. 1971. Cadmium poisoning in Fundulus heteroclitus
and other marine organisms. J. Fish. R_e_s_._TJ_. Can. 28:
1225-234.

Eisler, R., and M. L. Weinstein. 1967. Changes in metal
composition of the quahaug clam, Mercenaria mercenaria
after exposure to insecticides. Chesapea Sci. 8(4T;-
253-2582 2 fig.., 2 tables, 18 refs.

Fitz, E. S. 1956. An introduction to the biology of Raja
eglanteria Bosc 1802 and-Rajja erinacea Mitchill 1825 as
they occilr- in Delaware Bay. M-a-s-t-e-r-s-7hesis, Univ. of Del.
93 p.

Mackay, D. W., W. Halcrom, and I. Tho rnton. 1972. Sludge
dumping in the firth of Clyde. Mar. Poll. Bull. 3(l):7-11,
6 fig., 5 tabls., 13 refs.

Mihursky, J. A. et al. 1971. Effects of thermal pollution
on productivity and stability of estuarine communities.
Compl. Report. May 1965 - June 1969. OWRR, U. of Md.,
College Park.

Price, K. S... Jr. 1962. Biology of the sand shrimp, Crangon
septemspinosa, in the shore zone of the Delaware Bay re-
gion. Chesapeake Sci. 3:244-25S.

Whiteley, G. C. 1948. The distribution of larger planktonic
Crustacea on Georges Bank. Ecol. Monogr. 18:2'33-264.

Williams, A. B. 1965. Marine decapod crustaceans of the
Carolinas. Fish. Bull. U. S. F. W. L. S. Vol. 6S. No. 1.
298 p.

Wilsont.K. W., and P. M. O'Connor. 1971. The use of a
continuous flow apparatus in the study of longer-term
toxicity of heavy metals. Reprint, International Council
for Exploration of the Sea, Fisheries Improvement Committee,
Reference "C". 9 p., 6 fig. 7 refs.

Appendix 15
115

Category: Invertebrates

Common Name: Mud crab (Miner, 1950)

Inventory Prepared by: Robert E. Miller
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification

Phylum: Arthropoda
Class: Crustacea
Division: Eucarida
Order: Decapoda
Suborder: Reptantia
Tribe: Brachyura
Subtribe: Brachygnatha
Superfamily: Brachyrhyncha
Family: Xanthidae
Species.: Rhithropanopeus harrisii (Gould)
Distribution

Known range: Netherlands; Schleswig-Holstein, West Germany;
Copenhagen, Denmark; Vistula mouth and adjacent waters,
Poland; northwestern France; southwestern France (once);
Black Sea, Sea of Azov; Caspian Sea; W. Coast of Atlantic,
in estuaries from Nova Scotia to Mexico; northeastern
Brazil; W. coast of America in San Francisco Bay and in
Coos Bay, Oregon (Christiansen, 1969 and Williams, 1965).

Distribution in Chesapeake Bay:. Primarily in the upper Bay
and in tributaries of the lower Bay in depths of 0 to 10
meters * Specimens have been found in waters ranging from
fresh to 18.6 o/oo. Larvae have been found in water from
4 to no higher than 28.S o/oo salinity. Surface to 1S
meters (Christiansen, 1969; Williams, 1965; and Ryan,
19S6).
Poeulation: D .uring the years 1945 to 1951, approximately
1,,00U specimens were collected at 113 stations in Chesapeake
Bay (Ryan, 19S6).

Reproduction

Method: Sexual

Seasons and conditions: Ovigerous females are taken from
May through September. Copulation occurs at tempera-
tures between 140C and 320C. Molting immediately before
copulation is not required for this species as -it is for
many other hard shell1crabs (Turoboyski, 1973).

Appendix 15
116

Reproduction (Continued)

Fecundity: Females taken in the Dead Vistula had between
1,280 and 4,800 eggs. These females averaged 3.51 mm
wider in carapace width than those in the Chesapeake
Bay. The egg mass varied with the size of the females.

Life Stages

Stages of life cycle: Four zoeal stages and one megalopa.

Early life stages

Physical appearance: Typical xanthid zoea. A very long
rostral spine and second antennal spines serve as dis-
tinguishing features. The number of setae on the ex-
opodite of the first and second maxillipeds increases
as molting into successive stages occurs (Connolly,
1925 and Hood, 1962).

Development: The normal rate of development for the
larval stages of R. harrisii from hatching to crab stage
is about 18 days 57t 25 G and 25 6/oo of salinity
(Costlow, Bookhout, and Monroe, 1966). The initial
portion of this period is marked by four zoeal stages,
each about 72 hours duration.

Eyestalk removal affects the rate of development in R.
harrisii (Kalber and Costlow,, 1966).

The removal of eyestalks also causes production of one
or two supernumerary zoeal stages. Injection of a
variety of extracts had little effect on normal larvae
(Costlow,, 1965).

Survival: Under laboratory conditions, the rate of sur-
vival for R. harrisii is very good (Costlow,.1965).
Bousfield T1955) tound good retention of zoea in the
Miramichi Estuary but little other work has been done
on survival rates.

Behavior: Retention of crab larvae in an estuary is
effected by the vertical distribution of the larvae.
This vertical movement is the result of behavioral
responses which place the larvae in water currents
beneficial to estuarine retention (Bousfield, 1955).

Adult stage
Physical appearance: Two transverse lines of granules
on each protogastric region, one on mesogastric region
interrupted at middle, two branchial, one of which is
opposite the tip of the posterior lateral tooth. Front

Appendix 15
117

Adult stage (Continued)

Physical appearance (continued)

little produced, edge nearly straight, channeled, upper
and lower margins granulate; median notch triangular.
Lateral teeth not prominent; a sinus in coalesced tooth;
third and fourth teeth pointing obliquely forward; last
tooth smaller. Outer orbital hiatus a nearly closed
fissure opening on 'a broad shallow notch. No subhepatic
tubercle.

In old crabs the chelipeds are nearly smooth. In small
specimens the wrist is rough with lines and bunches of
granules, distal groove deep; two granulate ridges on
upper margin of palm; upper edge of fingers granulate.
Fingers slender, prehensile edges evenly dentate. Legs
long, slender, compressed.

The third segment of the male abdomen does not touch
the coxae of the last pair of legs; terminal segment
subquadrate.

Color: Brownish, paler below; fingers white. Yellow
with red spots (Rathbun, 1930).

Development: Ryan (1956) summarized life history data
for R. harrisii in the Chesapeake Bay area. Ovigerous
females were collected from June to September (also in
April in Louisiana and Brazil). Though juveniles were
found in all months of the year, they occurred most fre-
quently in samples taken from July to October. Immature
forms of undetermined sex ranged from 2.2 to 2.6 mm. in
width. Immature males ranged from 3.2 to 5.0 mm and
similar females ranged from 3.3 to 5.7 mm. in width.
Ryan considered maturity to be reached the following
summer at a carapace width of 4.5 mm, for males and 4.4
to 5.5 mm in females.

Adults continue to grow and molt after maturity is
reached, and males finally attain a larger size than
females (up to 14.6 and 12.6 mm. wide, respectively).
No concrete data on,number of instars throughout life
are available but it is estimated that there may be
four instars between attainment of the 5 and 10 mm.
carapace widths (Williams, 1965).

Ecology
MaYi-tat (Physical/chemical)

Substrate: Ryan (1956) found this species in some kind
of shelter - oyster bars, living and decaying vegeta-
tion, old cans, and other debris.

'Appendix 15
118

Habitat (Continued)

Salinity range: Fresh to 18.6 o/oo (Ryan, 1956 and
Pinschmidt,, 1963). Bousfield (1955) found larvae
from 4 to 25.5 o/oo.

Temperature range: 0 to 34.10C.

Benthic composition: Shelter of some type, oysters,
cans or vegetation needed.

Turbidity/light: It has been suggested that R. harrisii
larvae exhibit a reversed pattern of diurnal v_er_t_1-_c_a_1_
migration dependent on a persistent internal rhythm
modified by lighting conditions (Forward, In press).

Water flow: Bousfield (1955) concluded that current
flow was utilized by R. harrisii zoeae to maintain
their horizontal dist'Fibution within the estuary.

Associate biological communities: R. harrisii.are often
found in oyster bar communities.

Food Requirements

Food: Probably dead organic matter of animal origin and
several aquatic plants in the detritus stage (Turoboyski,
1973).

Consumers

Natural predators and parasites: The oyster toad is a
natural predator. R. harrisil is cannibalistic when
finding a soft-shell crab, personal'observation in ten-
gallon aquariums. Eaten by several diving ducks.

A common parasite in the Chesapeake Bay is the sacculinid
barnacle, Loxothylacus panopaei.

Non-nutritional Role

Concentration of toxic substances: Not applicable; work
done on several other species of xanthid crabs but not
R. harrisii.

Non-nutritional Role of Other Species

Fertilization: Loxothylacus castrates the sexual organs.

Appendix 15
119

Bibliography

Bousfield, E. L. 1955. Ecological control of the occurrence
of barnacles in the Miramichi Estuary. Bull. Nat. Mus.
Can. 137, 1-69.

Christiansen., M. E. 1969. Crustacea Decapod Brachyura.
Universitetsforlaget Oslo.

Connolly, C. J. 1925. The larval stages and megalops of
Rhithropanopeus harrisii (Gould). Contr.@Can. Biol. Fish.
(N.s.) zo 329-3310

Costlowt J. D., Jr. 1966. The effect of eyestalk extirpation
on larval development of the mud crab, Rhithropanopeus
harrisii (Gould). Gen. & Comp. Endocr. 7, Zbb-Z14.

Forward., R. B., Jr. and J. D. Costlow, Jr. 1974. The ontog-
eny of phototaxis by one larvae of the crab, Rhithropanopeus
harrisii (Gould). In press.

Hood, M. R. 1962. Studies on the larval development of
Rhithropanopeus hartisii (Gould) of the family Xanthidae
TBrachyura). GuIF-Ire-s. Repts. 1(3):122-130.

Kalber, F. A., Jr. 1966. The ontogeny of osmoregulation and
its neurosecretory control in the decapod crustacean,
Rhithropanopeus harrisii (Gould). Amer. Zool. 6, 221-229.

Miner, R. W. 1950. Field Book of Seashore Life. Van Rees
Presst N. Y.P 888 p.

Pinschmidt, W., Jr. 1963. Distribution of crab larvae in
relation to some environmental conditions in the Newport
River Estuary, North Carolina. Duke Univ., unpubl. Ph.D.
Dissertation.

Rathbun, M. J. 1930. The cancroid crabs of America of the
families Euryalidae, Portunidae, Atelecyclidae, Cancridae
and Xanthidae. U. S. Nat. Mus. pp. 609.

Ryan, E. P. 1956. Observations on the life histories and
the distribution of the Xanthidae .(mud crabs) of Chesapeake
Bay. Amer. Midland Nat. 56(l):138-162.
Turoloyski, K. 1973. Biology and ecology of the crab
Rhithroeanopeus harrisii subsp. tridentatus. Mar. Bio.
73:3U3-313.

Williams, A. B. 1965. Marine decapod crustaceans of the
Carolinas. Fish. Bull. 65(l):298.

Appendix 15
120

Category: Fish

Common Name: Blue-backed herring

Inventory Prepared by: Linda L. Hudson and Jerry D. Hardy, Jr.
Department of Natural Resources
University of Maryland
Solomons, Maryland

Classification

Class: Osteichthyes (bony fishes)
Order: Clupeiformes
Family: Clupeidae
Species: Alosa aestivalis (Mitchill)
Subspecies: ITo-ne currently recognized
Synonyms: Clupea aestivalis Mitchill, 1815
Al'osa cyanonoton Storer, 1857
P-6-m-oTobus aesti-valis (Mitchill) Jordan &
EvermaF. 1896-190'U
Pomolobus cyanonoton Storer, Dean'. 1903
Other common names: menhaden, gTut herring, blueback,
summer herring, blackbelly, kyack.

Distribution

Known range: New Brunswick and Nova Scotia, Canada to
St. Johns River, Florida (Hildebrand, 1963; Scott and
Crossmann, 1973).

Distribution in'Chesapeake Bay: Occurs throughout the
region (Hildebrand and Schroeder, 1928).

Area of active reproduction: Spawns in both fresh and
brackish water in rivers and ponds (Davis, 1973;
Hildebrand, 1963;.Raney and Massmann, 1953). Chittenden
(1972) reported spawning 105 kilometers above the tide
in the Delaware River.

Occurrence in other areas: Outside the spawning season
occurs in a narrow band of coastal water offshore at
the bottom (Hildebrand, 1963; Hildebrand and Schroeder,
1928; Bigelow and Schroeder, 1957).

Population

Dynamics

Affecting factors: Hildebrand (1963) has noted that
overfishing, pollution, and impassable dams have
diminished the abundance of "alewives."

Appendix 15
121

Population (Continued)

Reproduct ion

Method: External fertilization.

Seasons and conditions: Late April through early May in
Potomac River (Hildebrand, 1963). Spawning takes place 41
at temperatures of 14 to 250C. Streams used for spawn-
ing typically have relatively deep ingresses, swift
currents., and rocky substrates (Bigelow and Schroeder,
1953; Loesch, 1970).

Fecundity: Probably an average of 100,000 (Smith, 1907).

Life Stages

Stages of life cycle: Egg, larva, juvenile, adult.

Physical appearance: Eggs demersal; adhesive; stick to
sticks, stones, gravel and other objects with which
they come in contact (Scott and Crossman, 1937);
average diameter about 1.0 mm; yellowish, semi-trans-
parent; perivitelline space about 4th egg radius;
capsule finely corrugated; yolk granular; oil globules
very small, scattered. Hatching length about 3.5 mm.
Body of larva long, slender; anus about 5/6th of body
length from snout; pectorals absent at hatching, con-
spicuous at 4.0 mm; dorsal finfold never extended to
head; chromatophores over yolk mass, along intestine
and, toward end of stage, at base of ventral finfold
posterior to vent. At 5.2 mm, yolk absorbed, mouth
open, auditory vesicles greatly enlarged. In juveniles
between lengths of 20.5 to 25.0 mm, the body depth
increases markedly and pigment develops on the head,
dorsum, and upper sides. Scales develop at about 45
MM. and in specimens of this size, the tongue is pig-
mented laterally and the peritoneum is usually dark
(Hildebrand, 1963; Kuntz and Radcliff, 1917; Mansueti
and Hardy, 1967).

Development: Hatching occurs in about 2 to 3 days at
temperatures of 22.2 to 23.90C (Scott and Crossman,
1973). When reared at "laboratory temperatures", eggs
develop as follows: early blastomeres large, spheri-
cal: three somites visible just prior to closure of
blastopore (16 hrs after fertilization); at 24- to 26-
somite stage embryo about 2/3rds around yolk, optic
and auditory vesicles developed; just prior to hatch-
ing, embryo longer than yolk circumference, relatively
opaque, slightly pigmented (Kuntz and Radcliff, 1917).
Young may reach a-length of 30 to 50 mm. in 1 month
(Scott and Crossman, 1973). Hildebrand and Schroeder

Appendix 15
122

Development (Continued)

(1928) presented the following growth data for the
Potomac River: In June, 30 to 37 mm; in July, 30 to
59 mm; in August, 34 to 64 mm; in September, 40 to
69 mm; in October, 40 to 74 mm; in November, 50 to
74. Hildebrand recorded lengths of 65 to 120 mm, at
I year.

Behavior: In the Chesapeake Bay area, the young remain
in upstream "nursery areas" until late summer or fall
(Hildebrand, 1963; Hildebrand and Schroeder, 1928;
Bigelow and Schroeder, 1957). Davis et al. (1967),
working in North Carolina, found that the seaward
migration is associated with increased water level
and decreased temperature. Some young may remain in
lower Chesapeake Bay during their first or possibly
their second winter (Hildebrand and Schroeder, 1928).
North of Chesapeake Bay, the movement to sea apparently
occurs much earlier: Scott and Crossman (1973) found
a rapid downstream movement when the young were 30-to
50-mm, long. Perlmutter et al. (1967) and Chittenden
(1972) found "young" in brackish water in summer.
Warrinner and Miller (1970) have presented detailed
data on the distribution of youngin the Potomac River.

Adult stage

Physical appearance: Dorsal 15 to 20, anal 16 to 21,
ventral 10 to 11, pectoral 14 to 18. Body elongate,
laterally compressed; depth 22.1 to 2S.2% of total
length; lower jaw extended beyond upper jaw; maxil-
lary to below middle of eye; scales large, deciduous;
lateral line not de"veloped; ventral scutes well devel-
oped; prepelvit scutes 18 to 21; postpelvic scutes 12
to 16. Back grayish, bluish-green or dark blue; sides
and belly silvery; rows of'scales on back and upper
sides with distinct dark lines; shoulder with a dark
spot usually followed by several other discrete, dark
spots; fins greenish or yellowish. Maximum length
380 mm. (Scott and Crossman, 1973; Hildebrand, 1963;
Mansueti and Hardy, 1967).

Development: Marcy (1969) found that 47% of the males
first spawn at age group 111, 50% at age group IV;
75% of the females mature at age group III. Hildebrand
(1963) stated@that maturity occurred at 205 mm, or less.

Behavior: A schooling species. In Chesapeake Bay re-
gion, move up to spawning areas during first half of
April (or when 'temperatures reach 70 F), remain until
June Ist or later, return to sea after spawning
(Bigelow and Schroeder, 1953; Hildebrand, 1963).

Appendix 15
123

Behavior (Continued)

There is some evidence that this species may overwinter
near the bottom (Scott and Crossman, 1973).

Ecology
Habitat (Physical/chemical)

Classification: Fresh,- brackish, and marine waters.

Salinity: Fresh to full-strength sea water. Chittenden
(1972) found this species to be highly tolerant to
abrupt changes in salinity.
Temperature: Minimum reported, 6 to 70C (Recksick and
McCleave, 1973). 'Gift and Westman (1971) have dis-
cussed responses to increasing thermal gradients.

Dissolved oxygen: Mortalities in excess of 35% occurred
when test animals were held at 02 concentrations of 2
to 3.0 mg/liter for 16 hours (Dorfman and Westman.,
1970).

FoodRequirements

Food: Mostly crustaceans and crustacean eggs; also cope-
pods, cladocerans, ostracods, amphipods,hydracarina,
dipterans (and presumably other insects), insect eggs,
fish eggs and larvae (Davis et al., 1967; Scott and
Crossman, 1967). Brooks and Dodson (1965) have studied
feeding habits in a fresh-water population and list
.various fresh-water zooplankters including Cyclops
and Daphnia.

Consumers

Predators and parasites: Alosa aestivalis is preyed upon
by predatory fish inhabiting fresh, br-a-c-kish, and marine
waters; this appears to be especially true of the weak-
fish' Cynoscion regalis (Hildebrand, 1963). Parasites
include the acanthocephalan, Echinor@xnchus acus, the
nematodeI Heterakis foreolata, and the copep-oa-,-Ergasilus
clupeidarum. The 9'Pecies may also be infested with the
coloniaT=ydroid, Obelia commensuralis (Gudger, 1937;
Sumner et al.1 l9lT_-,_J_oFnson and Ro-gers, 1972).
Man: Utilized by man, but generally not distinguished from
alewife., Alosa pseudoharengus, and therefore exact catch
statistics not available (Hildebrand and Schroeder, 1928).

Influence of Toxins

Other: Jensen (1969) points,out that some blueback eggs
and larvae are lost through power-plant intakes.

Appendix 15,
124

Bibliography

Bigelow, H. B. and W. C. Schroeder. 1953. Fishes of the
Gulf of Maine. U. S. Fish. and Wildl. Serv., Fish. Bull.
53(74):vii+ 577.

Brooks, J. L., and S. I. Dodson. 1965. Predationt body
size, and composition of plankton. Sci. 150(3692):28-35.

Chittenden, M. E.J. Jr. 1972. Salinity tolerance of young
blue-back herring, Alosa aestivalis. Trans. Amer. Fish.
Soc. 101(l):123-S.

Davis, J. 1973. Spawning sites and nurseries of fishes of
the genus Alosa in Virginia. Proceedings of a Workshop on
Egg, Larval-,-and Juvenile Stages of Fish in Atlantic Coast
Estuaries. National Oceanic and Atmospheric Administration,
Middle Atlantic Coastal Fisheries Center, Technical Publi-
cation (1):140-1.

Davis, J. R. and R. P. Cheek. 1967. Distribution, food
habits, and growth of young clupeids, Cape Fear River
System, North Carolina. Proc. 20th Ann. Conf. S.E. Assoc.
Game Comm. (1966):250-60.

Dorfman, D. and J. Westman. 1970. Responses of some anadro-
mous fishes to varied oxygen concentrations and increased
temperatures. New Jersey Water Resources Research Institute,
Rutgers University, Research Project Partial Completion and
Termination Report, OWRR Project B-012-N.J., 76 p.

Gift.9 J. J. and J. R. Westman. 1971. Responses of some estu-
arine fishes to increasing thermal gradients. Selected
Water Resources Abstracts 5(14):52.

Gudger, E. W. 1937. A glut herring, Pomolobus aestivalist
with an attached colonial hydroid, Obelia coRmensuralls.
Amer. Mus. Novitates (945), 6 p.
Hildebrand, S. F. 1963. Family Clupeidae, p. 257--'385, In
Fishes of the Western North Atlantic. Part Three. Soft-
rayed bony fishes. Class Osteichthyes. Order Acipenseroidei,
Order Lepisostei, Order Isospondyli, Suborder Elopoidea,
Suborder Clupeoidea, Suborder Salmonoidea. Memoir Sears
Found. (1):xxi+ 630.

. and W. C. Schroeder. 1928. Fishes of Chesapeake
Day. U. S. Bur. Fish. Bull. 43(Part 1), 366 p.

Jensen, A. C. 1969. Fish and power plants. The Conserva-
tionist. N. Y. St. Cons. Dept. 24(3):2-5.

Appendix 15
125

Johnson, S. K., and W. A. Rogers. 1972. Ergasilus clupeidarum
sp. n. (Copepoda: Cyclopoida) from Clupeid (blueFacks) fis
of the Southeastern U. S., with a synopsis of the North
American Ergasilus with a two-jointed first endopod. J.
Parasit. 58(2):3857-92.

Kuntz, A., and L. Radcliff.. 1917. Notes on the embryology
and larval development of twelve teleostean fishes. U.-S.
Bur. Fish. Bull. 33(1913):1-19.

Loesch, J. A. 1970. A study of the blueback herring, Alosa
aestivalis (Mitchill), in Connecticut waters. Diss. AT--
stracts Int. 30B:326S-3266.

Mansueti, A. J., and J. D. Hardy, Jr. 1967. Development of
Fishes of the Chesapeake Bay Region: An Atlas of egg, lar-
val, and juvenile stages. Part 1. Univ. of Maryland, 202 p.

Marcy, B. C., Jr. 1969. Age determination from scales of
Alosa aestivalis (Mitchill). Trans. Amer. Fish. Soc. 98(4):
622-63U-.

Perlmutter., A.V E.E.-Schmidt, and E. Leff. 1967. Distri-
bution and abundance of fish along the shores of lower
Hudson River during the-summer of 196S. N. Y. Fish. Game
J. 14:49-75.

Raney, E. C., and W. H. Massmann. 1953. The fishes of the
tidewater section of the Pamunkey River, Virginia. J. Wash.
Acad. Sci. 43(12):424-32.

Scott$ W. B., and E. J. Crossman. 1973. Freshwater fishes
of Canada. Bull. Fisheries Res. Bd. of Canada (184.):xiii+
966.

Smith, H. M. 1907. The fishes of North Carolina. North
.Carolina Geological and Economic Survey 2:xiv+ 453.

Sumner, F. B.19 R. C. Osburn, pLnd L. J. Cole. 1913. A bio-
logical survey of the waters of Woods Hole and vicinity.
Part 23, Section 3. A catalogue of the marine fauna. Bull.
U. S. Bur. Fisheries 31(1911):549-794.

Teck'siek,, C. and J. D. McCleve. 1973. Distribution of
pelagic-fishes in the Sheepscot River - Black River estuary,,
Wiscasset, Maine. Trans. Amer. Fish. Soc. 102(3):S41-51.
Warrinner, J. E.S J. P. Miller, and J. Davis. 1970. Distri-
bution of juvenile river herring in the Potomac River.
Proc. 23rd Ann. Conf.0 SE Assoc. Game & Fish Comm. (1969):
384-8.

Appendix 15
126

Category: Fish

Common Name: Mummichog

Inventory Prepared by: Linda L. Hudson and Jerry D. Hardy, Jr.
Department of Natural Resources
University of Maryland
Solomons Maryland

Classification

Class: Osteichthyes (bony fishes)
Order: Atheriniformes
Family: Cyprinodontidae
Species: Fundulus heteroclitus (Linnaeus) 1766
Subspecies: Several subspecies have been proposed (fonti-
cola, bermudae, macrolepidotus grandis, and badius.Of
these, only bermudae of Bermuda is recognized.-
Synonyms: Cobitus heteroclita Linnaeus, 1766
Cobitus macrolepidota Walbaum, 1792
Cobitus killfish Walbaum, 1792
Esox pisciculus Mitchill, 1815
Esox pisculentus Mitchill, 1815
Hydrargyra nigrofasciatus LeSueur, 1817
Hydrargyra ornata LeSuer, 1817
Hydrargyra swampina Lacepede, 1817
Poecilia caenicola Bloch and Schneider, 1801
Zygonectes funduloides Evermann, 1891
Fundulus bermudae Gunther, 1874
Fundulus rhizophorae Goode, 1877
Fundulus viridescens DeKay, 1842
Fundulus zebra DeKay, 1842
Fundulus floridensis Girard, 1859
Fundulus mudfish Lacepede, 1859
Fundulus nisorius Cope, 1870
Fundulus heteroclitus macrolepidotus (Walbaum)
Fundulus heteroclitus badius Garman, 1895
Other common names: Common mummichog, common killifish,
salt-water minnow, mummy, minnow, pike minnow, mud-
minnow, mud-dabbler, cobbler.

Distribution

Known range: Newfoundland and Nova Scotia to Mantanzas
River, Florida; Bermuda (Briggs, 1958; Collette, 1962;
Livingstone, 1951; Miller, 1955; Scott and Crossmann,
1964). Introduced into Ohio River drainage in western
Pennsylvania (Raney, 1938).
Distribution in Chesapeake Bay: Found throughout the Ches-
apeake Bay region (Hildebrand and Schroeder, 1928).

Appendix 15
127

Distribution in Chesapeake Bay (Continued)

Area of active reproduction: Spawns in salt, brackish
and fresh water in ponds, shallow pools, rivers, and
"pure" sea water.

Occurrence in other areas: All salinities from fresh to
salt water. In inshore areas, recorded from large
rivers, fresh-water streams and creeks lakes, salt
marshes, barrier beach ponds, and ditcLs. Detailed
descriptions of the habitat are available in the fol-
lowing papers: Brown (1957), Carr and Goin (1955),
Chidester (1920), Fisher (1920), Fowler (1912, 1952)p
Greeley (1935), Heilner (1920), Hildebrand and Schroeder
(1928), Hoedeman (1954), Livingstone (1951), Moore
(1922), Newman (1914), Raney (1950), Scherzinger (1915),
Seal (1908), Tracy (1910).

Population

Structure: Schmelz (1964) observed a sex ratio of 0.98S
females to one male.

Densities: Munro (1973) found that Fundulus heteroclitus
comprised '81.5% of the total fish Fauna-in her study area.
The density appeared to vary considerably with the tide.

Reproduction

Method: External fertilization.

Season and conditions: April to August. Peak activity
variously reported: late May or late June (Chidester,
1916; Fowler, 1916; Hildebrand and Schroeder, 1928;
Newman,, 1919; Schwartz, 1967). Spawning takes place
in shaded areas over gravel or hard bottom having
sparse to dense vegetation; also among emergent vege-
tation so close inshore that eggs may be stranded by
tide (Fanara, 1964; Fowler, 1906; Moore, 1922; Newman,
1907; Nichols and Breder, 1927; Pearcy and Richards,
1962).

Fecundity: Estimates of the number of mature eggs vary
from 4 to 800 (Hildebrand and Schroeder, 1928; Kagan,
1935; Moenkhaus, 1904; Munro, 1973; Schwartz, 1967).
Munro estimates 4 to 215 mature eggs in specimens from
the Patuxent River, Maryland. Ehnle (1910) pointed out
that a maximum of 30,eggs are deposited during one
spawning.

Life Stages

Stages of life cycle: Egg, larva, juvenile, adult.

Appendix 15

Early stages

Physical appearance: The eggs are demersal, sometimes,
attached to plant stems and to one another; sometimes
under algal mats and exposed to air; and sometimes
buried in mud (Battle, 1949; Bigelow and Schroeder,
1953; Breder, 1917; Brinley, 1933; Carranza and Winn,
1954; Chidester, 1916; Newman, 1918; Ryder, 1886;
Schwartz,, 1.967; Pearcy and Richards', 1962; Solberg,
1938; Stockard, 1921; Tracy, 1910). Eggs spherical;
diameter 1.5 to 2.5.mm; yellowish, amber, or almost
colorless, essentially,transparent; chorion heavy,
firm adhesive in newly deposited eggs, and with or
without (depending on geographic location) a thick
mat of attachment filaments; oil globules opaque,
unequal, small, numerous (Armstrong and Child, 1965;
Battle., 1944; Bigelow and Schroeder, 1953; Brinley,
1938; Brummett, 1966; Kuntz, 1918; Nelson, 1953;
Newman, 1908, 1915, 1918; Nichols and Breder, 1927,
1929; Ryder, 1886; Stockard, 1915a, 1915b, 1915c,
1921; Solberg, 1938; Tracy, 1910). Hatching length
4.0 mm or less to 7.3 mm (larger individuals may hatch
without yolk). Total myomeres, about 35. In yolked
hatchlings, head flexed over yolk; oil globules still
evident; pectoral rays developed; origin of dorsal
finfold over midpoint of body; urostyle oblique; a
double line of melanophores mid-dorsally and mid-
ventrally, and a series of red chromatophores mid-
laterally; yolk sac pigmented. In more advanced
larvae, a triangle of chromatophores on head and
scattered chromatophores along mid-dorsal ridge.
Towards end of larval stage (up to*20 or 25 mm.),
6 to 8 vertical pigment bars on flanks. Juvenile
males olive above, yellow below; young females
paler than males. This composite, brief description
is based on information presented by Agassiz, 1882;
Armstrong and Child, 1065; Bancroft, 1912; Bigelow
and Schroeder, 1953; Carpenter and Siegler, 1947;
Chidester, 1916; Cooke, 1965; Denny, 1937; Evermann,
1901; Gabriel, 1942; Gilson, 1926; Hildebrand and
Schroeder, 1928; Jordan and Gilbert, 1883; Newman,
1900; Oppenheimer, 1937; Richards and McBean, 1966;
Smith, 1892; Solberg, 1938al- 1938b; Stockard, 1907a,
1907b, 1907c; Truitt et al., 1929. In our own recent
laboratory studies, we have not observed the mid-
lateral red chromatophores described by earlier
workers. -We have noted, in very recent hatchlings,
the presence of large white chromatophores on the
body and at the base of the pectoral fin, and a
mass of yellow spots on the body just behind the
anus.

Appendix 15
.129

Early stages (Continued)

Development: A number of authors have presented detailed
developmental sequences or have commented,on certain
aspects of development (Bancroft ' 1912; Gilson, 1926;
Hyman, 1921; Jones, 193-9; Kagan, 1935; Manery et al.,
1933; Milkman, 1954; Moenkhaus, 1904, 1911; Newman,
1908.9 1914; Oppenheimer, 1936a, 1936b, 1936c, 1937;
Solberg, 1938; Stockard, 1915, 1921; Richards and
Porter, 1935; Rogers, 1952; Wyman, 1924). The follow-
ing condensed description is based on the Solberg
series (1938). Rearing temperature was 250C.
1 hour blastodisc formed; 2 hours - 4-cell stage;
4 hours 64-cell stage; 10 to 14 hours- blastula
flattened into yolk; 17 hours - embryonic shield
formed; 24 hours - eye and brain divisions evident;
26 hours - blastopore closed; 28 hours - 4 somites
formed; 33 hours - auditory placodes formed; 38 hours
optic lobes formed; 40 hours - pigment on yolk;
42 hours - pigment on embryo; 44 hours - heart
pulsating; 46 hours - circulation established;
60 hours - otoliths developed; 72 hours - 35 somites;
78 hours - pectoral buds evident; 84 hours - eye pig-
mented; 90 hours - liver evident; 102 hours - pectorals
rounded; 114 hours - peritoneum pigmented; 126 hours -
caudal rays formed; 144 hours - gas bladder formed;
168 hours - vertebrae well-differentiated; 192 hours -
head noticeably more straightened than in earlier
stages; 240 hours - mouth open; 264 hours - hatching.
Incubation varies with temperature as follows: At
250C$ 11 days (Solberg, 1938); at 24.50C, 9 to'20 days
(Gabriel, 1942); at 19.4 to 21.4 C. average 17 days
(Scott and Kellicott, 1917); at 13 to 170C. about 24
days (Ryder, 1886). The maximum incubation period is
40 days, but no temperature was specified (Scott and
Kellicott, 1917). Nothing is known concerning the
growth of the young fish.

Behavior: Newly hatched larvae are phototropic and
remain off bottom. More advanced larvae swim at the
surface, but will occasionally make forays to the -
bottom. Juveniles have been recorded from eelgrass
along sandy beaches; in warm, shallow pools; and in
ditches associated with salt marshes (Armstrong and
Childsp 1965; Bean, 1903; Fisher, 1920; Moore, 1922;
Richards and McBean, 1966; Stockard, 1907).

Adult stage

Physical appearance: Dorsal 10 to 14; anal 9 to 12;
caudal 17 to 20; pectoral 16 to 20; ventral 6 to 7.
Body robust, deep, short. Teeth pointed and in
villiform bands. Dorsal origin somewhat anterior to

''Appendix 15
130

Physical appearance (Continued)

anal origin. Typically olivaceous to dark green above,
pale to yellow-orange below, but color highly variable.
Scales sometimes with white spots arranged in vertical,
longitudinal, or diagonal stripes; dorsal fin sometimes
with a dark ocellus; sides of females with 13 to 15
crossbands (Bigelow and Schroeder, 1953; Brown, 1954;,
Carpenter and Siegler, 1947; Carr and Goin, 1955;
Chidester, 1916; Garman, 1895; Hildebrand and Schroeder,
1928; Hubbs, 1926; Parker, 1925; Schwartz, 1961; Scott
and Crossmann, 1973; Smith, 1892, 1907; Truitt et al.,
1929).

Development: "Yearlings" may possible spawn in late
August, otherwise probably mature during 2nd winter.
Females mature at a minimum of 28 mm SL; males at a
minimum of about 32 mm. TL (Chidester, 1916; Hildebrand
and Schroeder, 1928; Schmelz, 1964; Tracy, 1910).

Behavior: Typically a schooling species. Apparently
ubiquitous in some areas, but showing marked preference
for muddy water and muddy bottom in some areas. Some-
times moves overland or buries in mud when stranded by
tide; can remain out of water for up to 4 hours. Some-
times found in extremely foul water. Migratory, moving
into marshes and fresh-water creeks when spring temper-
atures reach 15 C (sometimes as early as March). Peak
migrations in mid-April. Run in and out with the tide.
Hibernate in deep holes near mouths of rivers or bury
6 to 8 inches in mud in salt marshes or sheltered la-
goons in winter. Seldom more than 100 yards from shore
or in water deeper than "a couple of fathoms" (Bean,
1902; Bigelow and Schroeder, 1953; Butner and Brattstrom,
1960; Carranza and Winn, 1954; Chidester, 1916, 1920,
1922; deSylva et al., 1962; Fowler; 1914; Hildebrand
and Schroeder., 1928; Moore,,1922; Newman, 1908, 1918;
Nichols and-Brederl, 1927; Radcliff, 1915; Schwartz,
1961; Smith, 1907).

Ecology
Ha at (Physical/chemical)

Classification: Fresh, brackish, and marine waters.

Salinity: Loeb (1900) found that newly hatched larvae
could survive in distilled water, but died in sodium
chloride solutions equal in strength to seawater.
Maximum salinity, 35 o/oo (deSylva et al., 1962).
Burden (1956) has shown that Fundulus heteroclitus
can withstand abrup"t salinity anges.

Appendix 15

Habitat (Physical/chemical) (Continued)
Temperature: Eggs can be reared at 26 to 270C with only
2% mortality (Solberg, 1938). Advanced eggs can sur-
vive temperatures as low as 0 to 20C for rather long
periods, but early eggs are killed or develop abnor-
mally at reduced temperatures (Kellicott, 1916; Loeb,
1915). -Garside and Jordon (1968) found an upper lethal
temperature for adults of 33.9 C (at a salinity of 14
o/oo). Umminger (1969, 1970a, 1970b, 1970c, 1971) and
Benziger and Umminger (1973) studied physiology and
biochemistry at temperatures near freezing (minimum
acclimation temperature minus 1.50C). Pickford et al.
(1971) noted that mummichogs become cDmatose when
adapted at 200C and immersed for 3 minutes at 10C.
McNabb and Pickford (1970) studied thyroid function
as it is affected by high and low temperatures. Gift
and Westman (1971) studied responses to increasing
thermal gradients.

Dissolved oxygen: Bigelow and Schroeder (1953)-noted
that this species is resistant to "a lack of oxygen."
Voyer and Hennekey (1972) found that dissolved 02
concentrations of 0.74 to 0..89 were lethal to 50%
of their experimental adult animals. They presented
similar data for eggs.

Food Requirements

Food: Diatoms, foraminifers, amphipods, and other crusta-
ceans, molluskst insect larvae, fish eggs, small fishes,
and vegetation. Mud is sometimes ingested, but this is
probably by accident (Scott and Crossmann, 1973; Linton,
1901; Schmelz, 1964).

Consumers

Natural predators and parasites: Predators include blue-
fish (Grant, 1962), chain pickerel (Meyers and Muncy,
1962), white perch (Schmelz, 1964), brook trout, bull-
frogs, otter, mink, and kingfishers (White, 19S3; White
et al., 196S). Hoffman (1967) found that mummichogs
were infested with protozoans, trematodes, nematodes,
acanthocephalids, and crustaceans. Stromberg and Crites
(1972) recorded the cucullonid,, Dichelyne bullocki, from
the species, and two parasites,tDistomum -sp,)and ro-
Gyro
dactylus sp. were recorded by afford (190 and
Gowanlock. (1927). respectively. More recently, Lawler
(1967) described a new parasitic dinoflagellate ' Oodinium
cyprinodontum, which occurs on the gills of heter-o-cT-itus.

Man: While this species is not consumed by man, it is
sometimes harvested in large numbers for bait (Richards
and Castagna, 1970).

Appendix 15
132

Influence of Toxins

Biocides: Eisler (1970a, 1970b) and Eisler and Weinstein
(1967) studied the effects of several insccticides on
Fundulus heteroclitus under a variety of experimental
conditions.

Heavy metals: Data on the toxicity of 6eryllium, cadmium,
copper, lead, mercury, and zinc has been presented by
Eisler (1968, 1971), Eisler and Gardner (1973), Eisler
et al. (1972), Gardner and LaRoche (1973), Garside and
Yevich (1970), Jackim, (1973), Jackim et al. (1970) and
White (1912). Gardner and Yevich (1970) found patholog
ical changes in the intestinal tract, kidneys, and gills
After exposure to 50 ppm of cadmium. Gardner and LaRoche
(1973) found that hatchlings of Fundulus heteroclitus
were much more sensitive to copper toxicity than were
adults. Fletcher et al. (1971) studied the effects of
yellow phosphorus waste production on the species.

Radionuclides: Angelovic et al. (1969) studied the effects
of cobalt-60 and sodium-22, and pointed out that mummi-
chogs become more sensitive to radiation as temperature
or salinity increases.

Bibliography

Agassiz, A. 1882. On the young stages of some osseus fishes.
Proc. of the Amer. Acad. of Arts and Sci. 9(16):271-303.

Angelovic, J. W., J. C. White, and E. M. Davis. 1969. Inter-
actions of ionizing radiation, salinity, and temperature on
the estuarine fish, Fundulus heteroclitus. Proc. 2nd Nat.
Symp. Radioecology, Ann Arbor, Mich. CI'M):131-41.

Armstrong, P. B., and J. S. Child. 1965. Stages in the
normal development of Fundulus heteroclitus. Biol. Bull.
128(2):143-68.

Bancroft, F. W. 1912. Heredity of pigmentation in Fundulus
hybrids. J. of Exptl. Zool. 12(2):153-78.

Battle, H. 1. 1944. Effects of dropping on the subsequent
hatching of teleostean ova. J. Fish. Res. Bd. Canada 6(3):
252-6.

Bean, T. H. 1902. The fishes of Long Island. N. Y. Forest,
Fish and Game Comm. 6th Ann. Rept.:373-47-8.

1903. Catalogue of the fish'es of New York. N.Y.
St. Mus.', Bull. 60 (Zoology 9). 784 p.

Appendix 15
133

Benziger, D. and B. L. Umminger. 1973. Role of hepatic
glycogenolytic enzymes in the cold-induced hyperglycemia
of the killifish, Fundulus heteroclitus.. Comp. Biochem.
& Physiol. 45(3A):767_-77_.

Bigelow, H. B. 4 W. C. Schroeder. 1953. Fishes of the Gulf
of Maine. U. S. Fish. & Wildl. Serv., Fish. Bull. 53(73):'
vii+ 577.

Breder, C. M., Jr. 1917. Notes on Fundulus heteroclitus.
Aquatic Life 3(2):29.

Briggs, J. C. 1958. A list of Florida fishes and their
distribution. Bull. Fla. St. Mus., Biol. Sci. 2(8):223-318.

Brinley, F. J. 1938. Eggs of fishes. Tabulae Biol. 16(l):
51-9.

Brown, J. L. A review of the cyprinodont genus Fundulus of
eastern United States. M.S. thesis, Cornell Univ., V+ 98.

1957. A key to the species and subspecies of
tEe cyprinodont genus Fundulus in the United States and
Canada east of the Conl-In-e-n-f-a-T Divide. J. Wash. Acad. Sci.
4 7 (3) :69 - 7 7 .

Brummett, A. R. 19-66. Observations on the eggs and breeding
season of Fundulus heteroclitus at Beaufort, North Carolina.
Copeia l96T(3T=--20.

Burdent C. E. 1956. The failure of hypophysectomized
Fundulus heteroclitus to survive in fresh water. Biol.
Bull. 110(l):8-28.

Butner, A., and B. H. Brattstron. 1960. Local movements in
Menidia and Fundulus. Copeia 1960(2):139-41.

Carpenter, R. G., and H. R. Siegler. 1947. Fishes of New
Hampshire: A sportsman's guide to the fresh-water fishes
of New Hampshire. New Hampshire Fish and Game Comm., 87 p.

Carr, A. and C. J. Goin. 1955. Guide to the reptiles, am-
phibians., and freshwater fishes of Florida. Univ. of Fla.
Press, Gainsville, ix+ 341.

Carranza, J.* and H. E. Winn 1954. Reproductive behavior
of the blackstripe topminnLw, Fundulus notatus.. Copeia
1954 (4) :273-81.

Chidester, F. E. 1916. A biological study of the more
important of the fish enemies of the salt-marsh mosquitoes.
New Jersey Agric. Exptl. Sta. Bull. 300, 16 p.

Appendix 15
134

Chidester, F. E. 1920. The behavior of Fundulus heteroclitus
on the salt marshes of New Jersey. Amer.Nataur. 54(635):
551-7.

. 1922. Studies of fish migration. II. The
influence of salinity on the dispersal of fishes. Amer.
Natur. 56(645):373-80.

Collette, B. B. 1962. Hemiramphus bermudensis a new half-
beak from Bermuda, with a survey of endemism in Bermudian
shore fishes. Bull. Mar. Sci. - Gulf and Caribbean 12(3):
432-49.

Cooke, P. H. 1965. Head scale pattern as characteristic for
the identification of Fundulus heteroclitus and Fundulus
majalis. Trans. of the Amer. Fish. Soc. 94(3):265-7.

Denny, M. 1937. The lateral-line system of the teleost,
Fundulus heteroclitus. J. of Compar. Neurology 68(l):
49-65.

deSylva, D. P., F. A. Kalber, Jr., and C. N. Shuster, Jr.
1962. Fishes and ecological conditions in the shore zone
of the Delaware estuary, with notes on upper species col-
lected in deeper water. Univ. Dela. Mar. Lab., Inf. Ser.
Publ. No. 5 ii + 164.

Ehne H. 1910. Fundulus pallidus, Fundulus heteroclitus.
and Fundulus chrysotus. Blatter fur Aquarien und Terrarien
Kunde 21(43):685-6.

Eisler, R. 1967. Acute toxicity of zinc to the killifish,
Fundulus heteroclitus. Ches. Sci. 8:262-4.

. 1970a. Factors affecting pesticide-induced toxic-
ity in an estuarine fish. U. S. Bur. Sports Fish. & Wildl.,
Tech. Paper (45), 20 p.

. 1970b. Acute toxicities of organochlorine and
organgophosphorus insecticides to estuarine fishes. U. S.
Bur. Sport Fish. and Wildl., Tech. Paper (46), 12 p.

1971. Cadmium poisoning in Fundulus heteroclitus
(Pisces: Cyprinodontidae) and other marine organisms. J.
Fish. Res. Bd. Canada 28(9):1225-34.

and G. R. Gardner. 1973. Acute toxicology to an
estuarine teleost of mixtures of cadmium, copper, and zinc
salts. J. Fish. Biol. 5(1973):131-42.

,and M. P. Weinstein. 1967. Changes in metal com-
position of the quahaug clam, Mercenaria mercenaria, after
exposure to insecticides. Ches. Sci. 8(4):253-8.

Appendix 15
135

Eisler, R., G. E. Zaroogian, and R. J. Hennekey. 1972.
Cadmium uptake by marine organisms. J, Fish. Res. Bd.
Canada 29(9):1367-9.

Evermann, B. W. 1901. Bait minnows. Forest, Fish and Game
Comm. of New York, 6th Ann. Rept.:307-52.

Fanara, D. M. Notes on the biology of a salt-marsh minnow,
Cyprinodon variegatus. N. J. Mosquito Exterm. Assoc., Proc.
Slst Ann. Mtg.:15Z-9.

Fisher, G. C. 1920. Salt-water minnows in fresh water.
Copeia (79):18.

Fletcher, G. L.1 R. L. Hoyle, and D. A. Horne. 1971. The
relative toxicities of yellow phosphorus production wastes
to seawater-maintained fish. Fish. Res. Bd. Canada. Tech.
Rept. 2552 14 p.

Fowler, H. W. 1906. The fishes of New Jersey. Ann. Rept.
of the N. J. St. Mus. Part 11. 35-477.

. 1912-13. Records of fishes for the middle Atlantic
--S-tates and Virginia. Proc. Acad. of Nat. Sci. of Phila.
64:34-59.

1914. Notes on the fishes at Ocean City, Maryland.
---C-opeia 1914(2):

1916. Some features of ornamentation in the killi-
_-T-I'sKes or toothed minnows. Amer. Natur. 50(600):743-50.

. 11952. A list of fishes of New Jersey with offshore
records. Proc. Phila. Acad. Nat. Sci. 104:89-151.

Gabriel,, M. L. 1942. The effect of temperature on vertebral
numbers in Fundulus. The Collecting Net 17(5):85-6.

Gardner, G. R. and G. LaRoche. 1973. Copper-induced lesions
in estuarine teleosts. J. Fish. Res. Bd.. Canada 30(3):
363-8.

and Paul P. Yevich. 1970. Histological and
hematoro-gical responses of an estuarine teleost to cadmium.
J. Fish. Res. Bd. Canada 27(12):2185-2191.

Garman, S. 1895. The Cyprinodonts. Memoir of the Mus. of
Comp. Zool. 19(l):1-179.

Garside E. T. & C. M. Jordan. 1968. Upper lethal tempera-
tures at various levels of salinity in the euryhaline
cyprinodontids Fundulus heteroclitus and F. diaphanus
after isosmotic acclimation. J.-P'ish. Re"g. Bd. Canlda
25(12):1537-1551.

Appendix 15
136

Gift$ J. J. and J. R. Westman. 1971. Responses of some
estuarine fishes to increasing thermal gradients. Selected
Water Res. Abst. S(14):S2.

Gilson, A. S., Jr. 1926. Melanophores in developing and
adult Fundulus. J. Expt. Zool. 45(2):41S-SS.

Gowanlach, J. N. 1927. Notes on the occurrence and control
of the trematode, Gyrodactylus, ectoearasitic on Fundulus.
Proc. Trans. Nova Scotia Inst. Sci.

Grant, G. C. 1962. Predation of bluefish on young Atlantic
menhaden in Indian River, Delaware. Ches. Sci. 3(l):45-7.

Greeley, J. R. 1935. Fishes of the watershed with annotated
list, p. 63-101$ 4 plates. In A biological survey of the
Mohawk-Hudson watershed. Su@7pl. 24th Ann.- Rept., St. N. Y.
Conserv. Dept. (1934), 379 p.

Heilner, V. C. 1920. Immunity enjoyed by sticklebacks.
Copeia (82) :38.

Hildebrandt S. F., and W. C. Schroeder. 1928. Fishes of
Chesapeake Bay. Bull. U. S. Bur. Fish. 43(Part 1):1-366.

Hoedeman, J. J. 1954. Aquariumbibliotheek (Aquariumvissen-
enclopoedie). Uitgoverij de Bezige bij Amsterdam, 527 p.

Hoffmann, G. 1. 1967. Parasites of North American fresh-
water fish. Univ. Calif. Press, 486 p.

Hubbs, C. L. 1926. Studies of the fishes of the order
Cyprinodontes. VI. Material for a revision of the
American genera and species. Univ. Mich., Mus. Zool.,
Misc. Publ. No. 1619 79 p.

Hyman, L. H. 1921. The metabolic gradients of vertebrate
embryos. I. Teleost embryos. Biol. Bull. 40(l):32-74.

JackimX E. 1973. Influence of lead and other metals on
fish aminolevulinate dehydrase activity. J. Fish. Res.
Bd. Canada 30(4):560-2.

P J. M. Hamlin,, and S. Sonis. 1970. Effects of
meta-r-poisoning on five liver enzymes in the killifish
(Fundulus heteroclitus). J. Fish. Res. Bd. Canada 27:
383-90.

Jones, R. W. 1939. Analysis of the development of fish
embryos by means of the mitotic index, V. The processes
of early differentiation of organs in Fundulus heteroclitus.
Trans. Amer. Microscop. Soc. 58(1.):1-23.

Appendix 15
137

Jordon, D. S., and C. H. Gilbert. 1883. Notes on fishes
observed about Pensacola, Florida, and Galveston, Texas,
with description of new species. Proc. of U. S. Nat.
Mus. 5:241-307.

Kagan, B. M. 1935. The fertilizable period of the eggs of
Fundulus heteroclitus and some associated phenomena. Biol.
Bull. 69(l):l85-ZU1_.

Kellicott, W. E. 1916. The effect of low temperature upon
the development of Fundulus. A contribVtion to the theory
of teratogeny. Amer. J. of Anat. 20(3):449-82.

Kuntz,, A. 1918. Notes on the embryology and larval develop-
ment of twelve Teleostean fishes. Bull. U. S. Bur. of Fish.
23(1915-1916):87-133.

Lawler, A. R. 1967. Oodinium cyprinodontum n. sp., a para-
sitic dinoflagellate on gills ot Cypr-l-n-off-ontidae of Virginia.
Ches. Sci. 8(l) :67-8.

Linton, E. 1901. Parasites of fishes of the Woods Hole
Region. U. S. Fish. Comm. (1899):40S-92.

Livingstone, D. A. 1951. The fresh-water fishes of Nova
Scotia. Proc. of the N. S. Inst. of Sci. 23(l):1-90.
Loeb, J. 1900. On ion-proteid compounds and their role in
the mechanics of life phenomena. 1. The poisonous charic-
ter of a pure NaCl solution. Amer. J. of Phys. 3(7):327-38.

. 191S. On the role of electrolytes.in the diffusion
of acid into the egg of Fundulus. J. of Biol. Chem. 23(l):
139-44.

Manery, J. F., V. Warbri tton, and L: Irving. 1933. The
development of an alkali reserve in Fundulus eggs. J.
Cell. and Comp. Phys. 3(3):277-90.

McNabb, R. A. and G. Pickford. 1970. Thyroid function in
male killifish, Fundulus heteroclitus, adapted to high and
lower temperatures and to fresh w and sea water. Comp.
Biochem. Phys. 33(4):783-92.

Meyers, C. D. and R. J. Muncy. 1962. Summer food and growth
of chain pickerel, Esox niger, in brackish waters of the
Severn River, Maryl-an-&-. Ches. Sci. 3(2):125-8.
Milkman, R. 1954. Controlled observations of hatching in
Fundulus heteroclitus. Biol. Bull. 107(2):300.

Appendix 15
138

Miller, R. R. 1955. An annotated list of the American
Cyprinodontid fishes of the genus Fundulus with the
description of Fundulus ersimilis from Yucatan. Occ.
Papers, Mus. Zool., . Mich.) No. 568, 25 p.

Moenkhaus, W. J. 1904. The development of the hybrids
between Fundulus heteroclitus and Menidia notata with
5-e F-
especial reference to the Favior o t e aternal and
paternal chromatin. Amer. J. of Anat. 3(l):29-57.

. 1911, Cross fertilization among fishes. Proc.
of the Indiana Acad. of Sci. (1910):353-93.

Moore, J. P. 1922. Use of fishes for control of mosquitoes
in northern fresh waters of the U. S. U. S. Bur. Fish.
Doc. No. 923 (App. 4, Rept. U. S. Comm. Fish., 1922), 60 p.

Munro, E. 1973. Age. growth, and reproduction of Fundulus
heteroclitus in Gott's Gut Marsh. Nat. Res. Inst-.,-Un-iv.
Md. , ReF_77T-81.

Nels en, 0. E. 1953. Comparative embryology of the verte-
brates. The Blakiston Co., New York, Toronto, xxiii+ 982.

Newmant H. H. 1907. Spawning behavior and sexual dimorphism
in Fundulus heteroclitus and allied fish. Biol Bull.
12:314-45.

1908. The process of heredity as exhibited by
t development of Fundulus hybrids. J. Exptl. Zool. 5(4):
503-61.

1908. A significant case of hermaphroditism
in Flis-R-7-Biol. Bull. 15(5):207-14.

1914. Modes of inheritance in teleost hybrids.
J. of Expli. Zool. 16(4):447-90.

. 1915. Development and heredity in heterogenic
teleast hybrids. J. of Exptl. Zool. 18(4):511-76.

1918. Hybrids between Fundulus and mackerel.
A study of parental heredity in heterogenic hybrids. J.
Exptl. Zool. 26(3):391-417.

Nichols, J. T., and C. M. Breder, Jr. 1927. The marine
fishes of New York and southern New England. Zoologica
(N.Y.) , 9(l) :1-192.
Oppenheimer, J. M. 1936a. Processes of localization in
developing Fundulus. J,. Exptl. Zool. 73(3):405-44.

Anpendix 15
139

Oppenheimer, J. M. 1936b. The development of isolated
blastomeres of Fundulus heteroclitus. J. of Exptl. Zool.
7 2 (2) : 24 7 - 69.

1936c. Transplantation experiments on
developing tel sts (Fundulus and Perca). J. Exptl. Zool.
72 (3) :409 - 37.

1937. The normal stages of Fundulus
heteroclitus. -Biol. Bull. 68(l):8.

1937. Experimental analysis of early
stages in -te-I-eost development. The Collecting Net 12(l):
1, 5-6.

Parker, G. H. Melanism and color changes in killifishes.
Copeia 1925 (148):81-3.

Pearcy, W. G., and S. W. Richards. 1962. Distribution and
ecology of fishes of the Mystic River estuary, Connecticut.
Ecology 43(2):248-S9.

Pickford, G. E., A. K. Spivastava, A. M. Slicher, and P. K.
T. Pang. 1971. The stress response in the abundance of
circulating leucocytes in the killifish, Fundulus heterocli-
tus. I. The cold shock sequence and the ettects of
H-yp-ophysectomy. J. Expt. Zool. 177(l):89-96.

Radcliffe., L. 1915. Fishes destructive to the eggs and larvae
of mosquitoes. U. S. Bur. of Fish., Econ. Circ. (17), 19 p.

Raney, E. C. 1938. The distribution of fishes of the Ohio
drainage basin of western Pennsylvania. Ph.D. Thesis,
Cornell Univ... xii+ 1021.

1950. Freshwater Fishes, p. 151-194. In The
--J-ames River Basin, Past., Present, and Future.

Richards, A., and R. P. Porter. 193S. Analysis of early
development of fish embryos by means of the mitotic index.
II. The mitotic index of preneural tube stages of Fundulus
heteroclitus. Amer. J. Anat. 56(3):365-93.

Richards, C. E. and M. Castagna. 1970. Marine fishes of
Virginia's eastern shore (inlet and marsh, seaside waters).
Ches. Sci. 11(4):235-48.

Richards, S. W., and A. M. McBean. 1966. Comparison of post-
larvae and juveniles of Fundulus heteroclitus and Fundulus
majalis (Pisces: Cyprino2fontidae). Trans the Amer. Fish.
goc. 95(2):218-26.

Appendix 15
140

Rogers, K. T. 1952. Optic nerve pattern evidence for fusion
of eye primordia in cyclopia in Fundulus heteroclitus. J.
Exptl. Zool. 120(2):309.

Ryder, J. A. 1886. The development aE Fundulus heteroclitus.
Amer. Natur. p. 824.

Scherzinger, C. A. 1915. Fundulus heteroclitus. Aquatic
Life 1(4):65.

Schmeiz,, G. W. 1964. A natural history study of the mummi-
chog Fundulus heteroclitus (Linnaeus), in Canary Creek
MarN. M.S. Thesis, Uni'v. of Del. 65 p.

Schwartz, F. J. 1961. Fishes of Chincoteague and Sinepuxent
Bays. Amer. Midl. Natur. 65(2):384-408.

. 1967. Bull Minnows? Maryland Conservation-
ist 44(3):Z- .

Scott$ G. G., and W. E. Kellicott. 1917. The consumption of
oxygen during development of Fundulus heteroclitus. Anat.
Rec. 11(6) :531-30.
Scott$ W. B., and E. J. Crossmann. 1973. Fresh-water fishes
of Canada. Bull. Fish. Res. Bd. Canada (184):

Seal, W. P. 1908. Fishes and the mosquito problem. Their
serviceability as mosquito exterminators. Sci. Amer. Suppl.
(1691):351-2.

Smith, H. M. 1892. Notes on a collection of fishes from the
lower Potomac River...Maryland. Bull. U. S. Fish. Comm. 10
(1890):63-72.

. 1907. The fishes of North Carolina. North
Carolina Geol. and Econ. Surv. Vol. 2. xi+ 453.

Solberg, A. N. 1938. The susceptibility of Fundulus hetero-
clitus to x-radiation. J. of Exptl. Zool. 78(4):441-68.

1938. The development of a bony fish. Prog.
Fish Cult. (40):1-19.

Stafford, J. 1907. Preliminary report on the trematodes of
Canadian marine fishes. Contr. Canada Biol. 1902-5.

Stockard, C. R. 1907a. The influence of external factors,
chemical and physical, on the development of Fundulus
heteroclitus. Sci. 2S(646):780-1.

Appendix 15
141

Stockard, C. R. 1907b. The art ificial production of a
single median cyclopean eye in the 'fish embryo by means
of sea-water solutions of magnesium chloride. Arch. fur
Enwicklungsmechanik der Organismen.

. 1907c. The influence of external factors,
chemical and physical, on the development of Fundulus
heteroclitus. J. Exptl. Zool. 4(2):165-201. 4.

1909a. The development of artificially
produced cyi@lopian fish - "the magnesium embryo". J.
Exptl. Zool. 6(2):285-337.

. 1909b. The artificial production of one-
eyed monsters and other defects, which occur in nature, by
use of chemicals. Anat. Rec. 3(4):167-73.

1915a. An experimental study of the origin
of blood vascular endothelium in the-teleost embryo.
Anat. Rec. 9(l):124-7.

1915b. The origin of blood and vascular
endotheli in embryos without a circulation of the blood
in the normal embryo. Amer. J. of Anat. 18(2):227-37.

. . 1915c. A study of wandering mesenchymal
cells on living yolk sac and their development products:
Chromatophores, vascular endothelium and blood cells. Amer.
J. of Anat. 18(3):525-94.

. 1921. Developmental rate and structural
expression: An experimental study of twins, 'double mon-
sters' and single deformities, and the interaction among
embryonic organs during their origin and development.
Amer. J. Anat. 28(2):115-266.

Stromberg, P. C., and J. L. Crites. 1972. A new nematode
Dichelyne bullocki sp. n. (Cucullonidae) from Fundulus
teroclitus (Linnaeus). Proc. Helm. Soc. WasR_73TUT:
131-4.

Symons, P. E. K. 1971. Spacing and density in schooling
three-spine sticklebacks (Gasterosteus aculeatus) and
mummichog (Fundulus heteroclitus). J. Fish Re97. Bd.
Canada 28 (7T79=- 004.

Tracy, H. C. 1910. Annotated list of fishes known to in-
habit the waters of Rhode Island. Rhode Island Comm. of
Ini., Fish., 40ih Ann. Rept. (1910):35-176.

TruittP R. V.2 B. A. Bean, and H. W. Fowler. 1929. The
fishes of Maryland. State of Md., Cons. Dept. iv+ 120.

Appendix 15
1112

Umminger, B. L. 1969. Physiological studies on supercooled
killifish (Fundulus heteroclitus). II. Serum organic
constituents and the problem of supercooling. J. Expt.
Zool. 172(4):409-24.

. 1970a. Physiological studies on supercooled
kil ish (Fundulus heteroclitus). III. Carbohydrate
metabolism and survival at subzero temperatures. J.
Expt1. Zool. 173(2):159-74.

. 1970b. Effects of temperature on serum protein
components in the killifish, Fundulus heteroclitus. J.
Fish. Res. Bd. Canada 27 (2) :404-9.

. 1970c. Osmoregulation by the killifish, Fundulus
heteroclitus, in fresh water at temperatures near freezing.
Nature 225(5229):294-5.

. 1971. Patterns of osmoregulation in fresh-water
fishes at temperatures near freezing. Physiol. Zool. 44(l):
20-27.

Voyer, R. A. and R. J. Hennekey. 1972. Effects,of dissolved
oxygen on two life stages of the mummichog. Prog. Fish.
Cult. 34(4):222-5.

White, G. F., and A. J. Thomas. 1912. Studies on the absorp-
tion of metallic salts by fish in their natural habitat.
I. Absorption of copper by Fundulus heteroclitus. J. Biol.
Chem. 11:381-6.

1953. The eastern belted kingfisher in the
Maritime Provinces, Fish. Res. Bd. Canada Bull. (97), 44 p.

. J. C. Medcof, and L. R. Day. 1965. Are killi-
fish poisonous? J. Fish. Res. Bd. Canada 22(2):655-7.

Wyman, L. C. 1924. The reactions of melanophores of embry-
onic and larval Fundulus to certain chemical substances.
J. of Exptl. Zool. 40(1):161-80.

Appendix 15
143

Categ2r
y: Fish

Common Name: White perch

Inventory Prepared_by: Linda L. Hudson and Jerry D. Hardy, Jr.
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification

Class: Osteichthyes
Order: Perciformes
Family: Percichthyidae
Species: Morone americana (Gmelin)
Subspecies: None-currently recognized.
Synonyms.: Perca americana Gmelin, 1789
P-erca immacuiata Walbaum, 1792
Morone rufa Mi-t-c-hill, 1814-
MoroniF -pa=ida Mitchill,' 1814
Roccus americanus (Gmelin)
Other common names: Wriite p h. silver perch, sea perch,
blue-nosed perch, gray perch, black perch.

Distribution

Known range: New Brunswick, Nova Scotia, and Prince Edwards
Island to Georgia (records from Florida and the Gulf Coast
are questioned). Introduced into the Great Lakes, into
freshwater lakes and ponds in New England, and into lakes
and rivers in Nebraska (Mansueti 1964; Woolcott, 1962;
Webster,, 1942; Thoits and Mullan: 1958; Raney, 1965;
Dence, 1952; Larsen, 1954; Scott and Christie, 1963;
Hergenrader and Bliss, 1971).

Distribution in Chesapeake Bay: Found throughout the region
(Hildebrand and Schroeder, 1928).

Area of active reproduction: In Chesapeake Bay region in
tidal fresh or slightly brackish water, mostly in'lower
parts of large rivers on sand and gravel bars, on rocky
ledges, or under banks or debris (Mansueti, 1961, 1964;
Woolcott, 1962; Webster, 1942; Smith, 1971; Hildebrand
and Schroeder, 1928. Raney (1965) suggested that spawn-
ing takes place at the surface, while Mansueti (1961)
felt that it occurred under shelters beneath the surface.

Occurrence in other areas: Bays, estuaries, brackish and
fresh-water ponds, lakes, unprotected coastal waters,
creeks., and streams (Woolcott, 1962; Raney, 196S;
Radcliff and Welsh, 1917; Whitworth et al., 1968;
Miller, 1963). Congregates around piers, timbers,
bridges, and water lilies. Hibernates in deep water
or bays (Goode et al., 1884; Smith, 1971).

Appendix 15

Population

Structure: Reported sex ratios vary from 0.76 to 0.89
males to 1 female (Cooper, 1941; Thoits and Mullan,
1958).

Den'sities and totals: A total of 13,259 pounds of white
perch were recovered from a 185-acre lake. This repre-
sented 51% of the total weight of fish recovered (Thoits
and Mullan,' 1958). In other ponds, white perch accounted
for less than 1.0t of the total fish population (Stroud
and Bitzert 19SS).

Dynamics

Trends and fluctuations: The white perch tends to become
over-populated when stocked. This results in conspic-
uously stunted growth (Everhart, 1950; Stroud, 1955a;
Thorpe, 1942).

Factors affecting density: Biological and physical con-
ditions of the environment, fishing pressure, spawning
success, and predation may all influence population
densities (Stroud., 1952, 1955b).

Reproduction:

Method: External fertilization.

Season and conditions: Over entire range, late March
(Mansueti, 1961; Dovel, 1971; Conover, 19S8) to late
July (Mansueti, 1964). In Chesapeake Bay region late
March (MansuetiP 1961), but in some years, eggs not
evident in upper Bay until early April (Radcliff and
WelshP 1917; Rinaldo, 1971; Johnson, 1972). Winter
spawning in lower Chesapeake Bay has been suggested
(Hildebrand and Schroeder, 1928), but Mansueti (1961,
1964) has questioned this. Estuarine populations gen-
erally spawn in April and May and fresh-water popula-
tions in May, June, and July (Raney, 1965; Richards,
1960; Lagler, 1961). Spawning takes place during
daylight hours or at dusk (Mansueti, 1961; Raney,
1965). Spawning congregations typically occur in
lower reaches of large coastal rivers in estuarine
populations (Woolcott, 1962); also in fresh-water
spillpools of larger creeks (Smith, 1971). Spawning
usually occurs over fine sand or gravel, but has also
been observed over pulverized snail shell, and over
predominantly clay bottom (Webster, 1942; Thoits and
Mullan, 1958; Richards, 1960). Spawning temperatures
vary from 10 to 190C (Mansueti, 1961, 1964; Smith,
1971); in York River Virginia, peak activity was
observed at 11 to-166C (Rinaldo, 1971). The maximum

A'Dpendix 15
145

Seasons and conditions (Continued)

salinity in which spawning has been observed is 4.2
o/oo (Smith, 1971). A report of spawning in oceanic
water (Schwartz, 1960) is questioned.

Life Stages

Stages of life cycle: Egg, larva, juvenile, adult.

Early stages

Physical appearance: Eggs demersal, usually attached to
grass, rocks, and debris, either singly or in small
clumps or thin layers (sometimes, however, not attached
and float from point of deposition). Eggs spherical;
diameter 0.65 to 1.09 mm; chorion thick, tough, yellow-
ish-brown to brownish-grey, rarely transparent, occa-
sionally opaque; eggs initially adhesive but with
adhesiveness varying greatly during development; yolk
usually wi-th a single large amber oil globule 0.20 to
0.44 mm in diameter; sometimes several to many addi-
tional smaller oil globules; perivitelline space about
24% egg diameter (Schwartz, 1960; Mansueti, 1964;
AuClair, 1958, 1960; Everhart, 1958; Dovel, 1971; Wong,
1971). Hatching length 1.7 to 3.0 mm. Total myomeres
11 to 14, posterior myomeres 10 to 12. Body tadpole-
like, mouth and pectoral buds lacking at hatching.
Yolk sac not projected beyond head. At hatching,
virtually without pigment. At about 2.8 to 3.0 mm
(age 1 day) larvae transparent with orange and brown
chtomatophores; pigment concentrated on head, anterior
region of oil globule, posterior part of yolk sac,
ventral edges of hind gut and trunk, and sparsely on
dorsal edge of trunk. Yolk absorbed by 3.4 mm. At
3.4 to 19.0 mm, anus 55% of body length. At 12.0 to
14.0 mm, pigment very sparse. Juveniles at 20.0 mm
have small chromatophores.scattered on snout, head,
operculum, dorsolateral part of body, entire posterior
part of trunk, on spinous and soft dorsal, anal, and
caudal, and along lateral 1ine. At ca. 2S to 75 mm,
5 to 7 dusky vertical bars on sides and, sometimes,
faint horizontal stripes. Young-of-the-year have
dark brown horizontal stripes on sides which are lost
by age group I. "Young" less than 100 to 125 mm, long
are usually silvery-grey and lack blue pigment on the
head (Mansuetil 1964; Webster, 1942; Raney, 1965;
Taub, 1966; Hildebrand and Schroeder, 1928).

Development: A typical developmental sequence follows,
based on a temperature of 650F. About 10 minutes -
perivitelline space developing. About 20 minutes -
one- and 2-cell stages. About 45 minutes - two- and

ApDendix 15
146

Development (Continued)

4-cell stages; 1 hour - 4- to 16-cell stages; 2 hours -
some approaching 32-cell stage; 3 hours - blastoderm
berry-like, up to 64 cells; 6 hours - morula stage; 10
hours - blastoderm over it yolk; 14 hours - blastopore
closed; 18 hours - embryo surrounds 3/4th of yolk; 24
hours - embryo pigmented, somites visible; 30 hours -
tail free; 36 hours - pigment increased, tail longer;
44 hours - prehatching embryo, about 25 somites; 44-50
hours - hatching (based on Mansueti 1964). The incu-
bation period varies greatly with t;mperature as follows:
At 450F. "little-development" (Thoits and Mullan, 1958).
At 520F. about 6 days (Conover, 1958).- At 580F, about
3 to 41-2 days (Thoits and Mullan, 1958- AuClair, 1956;
Richards., 1960; Foster, 1919). At 604, variously
reported: 24 to 30 hours (AuClair, 1956); 48 to 52
hours @Titcomb, 1910); 72 hours (Schwartz, 1960). At
ca. 63 F., about 48 hours (Raney, 1965). At 650F, 44 to
50 hours (Raney, 1965). At ca. 650F, 44 to 54 hours
(Mansueti, 1964). At 680F, 24 to 30 hours (Foster,
1919; Richards, 1960; Thoits and Mullan, 1958). At 68
to '770F) 20 to 42 hours (Taub, 1966). Hatchlings grow
rapidly and the yolk is absorbed in *4 to 13 days
(Rinaldo, 1971; Mansueti and Mansueti, 1955) and the
young reach lengths of about 37 to 62 mm by July and
August (Thoits and Mullan, 1958). By the end of the
first year of growth, the average length is about 80
to 85 mm (Wallace, 1971).
Survival: At temperatures o f SOOF or lower, few eggs
survive. At normal temperatures, a sudden drop of 4
or SOF may destroy the eggs (Auclair, 1956, 1960;
Rinaldo, 1971).. Egg mortality can also result from
siltation (Morgan, Rasin, and Noe, 1973). In some
areast''Iyoung" white perch are preyed upon by various
species of gamefish (Cooper, 1941).

Behavior: Yolk-sac larvae settle to bottom and lie on
their sides. Larvae remain in the spawning area. Spec-
imens 8 to 13-mm long over mud bottom; also recorded
from quiet water in shore zone and on current-swept
sand and gravel bars. Maximum depth for larvae, 12
feet. As larval development proceeds, there is a gen-
eral downstream movement (Mansueti, 1964; Mansueti and
Mansueti, 1955; Raney, 1965; Webster, 1942; Rinaldo,
1971). Juveniles remain in the nursery areas to at
least 20 or 30 mm, or sometimes apparently to an age
of one year. Generally found along shore line in
shallow sluggish water over silt and mud bottom or
F_ among plants; also sometimes along sandy shoals and
beaches, particularly at evening. Juveniles may form
large schools. Estuarine populations remain in schools

Appendix 1.5
147

Behavior (Continued)

during summer months, but move toward brackish water
between August and late November, at which time the
schools break up. Juveniles up to 75-mm long move
inshore in evening and when water is rough or turbid
(Man.sueti, 1964; Woolcott., 1962; Webster, 1942; AuClair,
1956P 1958; Raney, 1965; Brice, 1898; Goode, 1888;,
Abbott, 1876; Dovel, 1971; Rinaldo, 1971; Richards,
1960; Smith, 1971).

Adult stage

Physical appearance: First dorsal with 8 to 11 spines;
2nd dorsal with 1 spine and 11 to 13 rays; anal 8 to
10 rays; pectoral 10 to 18 rays; ventral I spine and
5 rays. Body oblong, ovate, compressed; back moder-
ately elevated. Teeth small, pointed. Two dorsal
fins barely connected. Silvery, greenish, greyish
or almost black above, sometimes brassy. Large indi-
viduals with bluish lustre on head. Sides paler and
sometimes with indistinct lateral stripes. Belly
silvery-white, immaculate. Melanophores on rays
and membranes of all fins. Anal and ventrals some-
times rosy at base (Woolcott, 1962; Hildebrand and
Schroeder., 1928; Thoits and Mullan, 1958; King, 1947;
Whitworth et al., 1968; Richards, 1960; Scott and
Christie., 1963; Raney, 1965). Maximum length 485
mm, (Taub,, 1966).

Development: Size at maturity varies greatly. The
minimum size at maturity is 72 mm. for males and 98
mm for females (Miller, 1963). Mansueti (1961),
working with Chesapeake Bay material, found 50% of
the males mature at 100.3 mm, SL and,50% of the fe-
males mature at 105.5 mm SL. In Lake Ontario, the
smallest male was 140 mm FL and the smallest female
172 mm FL (Sheri and Power, 1968). Maturity occurs
in age groups II to IV (Mansueti., 1961, 1964; Thoits
and Mullan, 1958; North Carolina Wildlife Resources
Commission, 1962).

Survival: Meyers (1967).reported on an extensive kill
of white perch. He attributed this to the bacteria
Pasteurella sp.

B-ehavior: A schooling species usually found in summer
at depths of 15 to 30 feet during daylight hours and
at 3 to 4 feet at night; and, in winter, at depths of
40 to 60 feet. Maximum depth - 138 feet. Maximum 41
distance from shore, 10 miles. Anadromous or semi-
anadromous in some areas but not in others (in Patuxent
River, may move up,to 60 miles during spawning run).

Appendix 15
148

Adult stage (Continued)

Behavior (continued)

Marine and estuarine populations move shoreward and
generally upstream in spring, entering tidal creeks
and fresh-water areas. Summer movements are generally
local and random., although adults may move inshore at
night when water is rough or turbid. Apparently con-
gregate in large numbers to spawn. Hibernate in deep
waters of Chesapeake Bay (Thoits and Mullan, 1958;
Schwartz, 1960; King, 1947; AuClair, 1956; Richards,
1960; Miller, 1963; Hildebrand and Schroeder, 1928;
Woolcott.9 1962; Raney, 1965; Goode et al., 1884;
Smith, 1971; Lagler, 1961; Mansueti, 1961; Webster,
1942; Anonymous, 1953).

Ecology
Hab t (Physical/chemical)

Classification: Fresh, brackish, and marine waters.

Salinity: Larvae usually at less than 1.5 o/oo (Rinaldo,
1971), experimental upper limit 8 o/oo (Mansueti,
1964). "Young" (larvae or juveniles?) collected at 13
o/oo (Dovel, 1971). Juveniles mostly at less than 3
o/oo (Rinaldo, 1971). Adults at maximum salinity of
at least 30 o/oo (Smith, 1971).

Temperature: 2.0 to 32.50C, but optimum highly variable.
In some areas seldom above 15.50C. in other areas sel-
dom below about 270C. In still other populations mor-
tality results from temperatures close to about 2iOC,
if sustained for several days (Smith, 1971; Richards
1960; AuClair, 1956). On the other hand, Dorfman and
Westman (1970) were able to hold white perch at temper-
atures up to 870F. and found that they could survive
brief exposures (2 minutes) to 1000F. Meldrin and Gift
(1971) noted that avoidance responses to temperature
increases ranged from 44 F to 950F, depending on time
of year and acclimation temperature. Avoidance re-
sponses to decreased temperatures occurred at 3 to SOF
below ambient acclimation temperature. McErlean and
Brinkley have correlated temperature tolerance and
thyroid activity.

Dissolved oxygen: Prefer 02 content of over 3 ppm
(Thoits and Mullan, 1958), but experience 50% mortal-
ity in 02 concentrations of O.S to 1.0 mg/liter; growth
is impaired when diurnal fluctuations of Qxygen average
less than 3.8 mg/liter (Dorfman and Westman, 1970).
pH range: 6 to 9 (Richards., 1960).

Ap pendix 15
149

Benthic composition: Larvae sometimes over sand and
gravel bars; juveniles over silt, mud, sand, or vege-
tation (Woolcott, 1962; Raney, 1965; Goode, 1888;
Richards, 1960; Smith, 1971).

Turbidity/light: Schubel and Wang (1973) found that
concentrations of suspended sediment up to 500 mg/
liter did not influence hatching success. Morgan,
Rasin, and Noe (1973) found that suspended sediment
levels as high as 5,250 ppm did not effect hatching
success, but that levels above 1,500 ppm did increase
the incubation period.
41
Depth: Maximum depth for larvae, 8 to 12 feet (Webster,
1942). for adults, 138 feet (Hildebrand and Schroeder,
1928).

Water flow: Morgan, Ulanowicz, Rasin, Noe, and Gray
(1973) have presented data on the effects of water
movement on eggs and larvae of this species.

Associated biological communities: Found in close asso-
.ciation with all species of fish with which it shares
its environment (Anonymous, 1917; Thorpe, 1942).

Food Requirements

Food: "Fry" feed on plankton (Hover, 1948; Stroud, 1955b).
Adults primarily insectivorous: mayfly nymphs, caddisfly
larvae, dragonfly nymphs, midge larvae. Also eat fish
(smelt, yellow perch, white perch, young eels), fish
eggs, crabs, crayfish, fresh-water shrimp, and small
amounts of vegetation (Cooper, 1941; McCabe, 1944-45;
Thorpe, 1942; Goode, 1888; Alsop and Forney, 1962; Reid,
1972; Linton, 1901).

Feeding: Appear to feed mainly during evening (Webster,
1942).

Consumers

Natural predators and parasites: In some areas, young of
the white perch are preyed upoil by game fish (Cooper,
1941). The following parasites have been recorded from
the white perch: Ergasilus sp., Lernaeca cruciata,
Glochidia sp., PiscicolariT sp., LeptorhyncHoides
thecatus Neoechinorhync"Eu-s cylindratus, tomum
cornutum', Crep'lTo-stomum cooperi, bunodera sacculata,
Bunodera'lucioperca, Minostomum marginaFun, Diplostomulum
scheuringi, Posthodiplostomum. minimum AZygia angusti-
cauda, Poteocephalus ambloplitis, othrium crassum,
Spinitectus gracilis !5pinitectus carolini, Metabronema
Sp., Camallanus truncatust Vichylene cotylopHo-ra.

Appendix 15
. 150

Natural predators and parasites (Continued)

Dichylene robusta. This list is based on the works of
DeRoth (1'9337_,_Ru_nter (1942), McCabe (1953),, Meyer (1954).
and Thorp (1942), as well as the review table by Thoits
and Mullan (1958).

Man: Widely utilized by man as sport and food fish. Total
Chesapeake Bay catches for 1953 amounted to 1,364,-000
pounds (Anderson and Power, 1956).

Influence of Toxins

Biocides: Morgan, Fleming, Rasin, and Heinle (1973) doc-
umented sublethal changes in blood morphology and bio-
chemistry in white perch from Baltimore Harbor water
which contained, among other pollutants, the insecticide
dieldrin.

Heavy metals: Morgan, Rasin, Noe, and Gray (1973) and
Morgan, Fleming, Rasin, and,Heinle (1973) discuss mor-
tality rates and sublethal changes in blood morphology
and biochemistry resulting from water from various
sources known to contain cadmium, chromium, copper,
iron, mercury, and zinc. Rehwoldt et al (1971) pre-
sented data on the toxicity of copper, nickel, and
zinc. Zitko et al (1971) recorded 0.75 to 1.07 ppm
(wet weight) of methyl-mercury in muscle tissue of
white perch.

Petroleum: Mortalities of white perch in Baltimore Harbor
resulted from the effects of a combination of pollutants,
one of which may have been petroleum waste (Morgan, Rasin,
,Noe, and Gray, 1973).

Other: Tsai (1970) commented that spawning runs of white
perch in the Patuxent River were probably blocked by the
outflow of chlorinated sewage effluents.

Bibliography

Abbott, C..C. 1878. Notes on some fishes of the Delaware
River. The larger acanthopterous fishes of the Delaware
River. Rept. U. S. Fish. Comm. 4(1875):825-45.

Alsop, R. G., and J. L. Forney. 1962. Growth and food of
the white-perch in Oneida Lake, N. Y. Fish. and Game J.
9(2):133-6.

Anderson, A. W. and E. A. Power. 1956. Fishery Statistics
of the United States 1953. Statistical digest No. 36, Fish
and Wildl. Serv.J. U. S. Dept. of Int., U. S. Govt. Prtg.
Off. . Wash. D. C.

Appendix 15
151

Anonymous. 1917. Reports of the Division of Fisheries and
Game, Massachusetts. Publ. Doc. (25):66-7.

1953. Homeloving fish. Maryland Tidewater News.

AuClair, R. P. 19S6. The white perch, Morone americana
(Gmelin) Sebasticook Lake, Maine. M.S_._7Fe`s`is, Univ.
Maine. 84 p.

. 1958. Sea bass family (Serranidae), p. 73-6, In
--1`V_e-rFart, W. Henry. 19S8. Fishes of Maine, Maine Dept.
Inland Fish. & Game, Augusta, Maine. 94 p.

1960. White perch in Maine. Maine Dept. Inland
-7-is-F.- and Game, Augusta, Maine. 16,p.

Brice., J. J. 1898. The fish and fisheries of the coastal
waters of Florida. U. S. Fish. Comm. Rept. 22(1896):263-
342.

Conoverl, N. R. 19S8. Investigations of white perch, Morone
americana (Gmelin), in Albemarle Sound and the lower-Wo-a-n-oke
River, N67rth Carolina. M.S. Thesis, N. C. State Coll.,
viii+ 58.

Cooper, G. P. 1941. A biological survey of lake and ponds
of the Androscoggin and Kennebec River drainage systems in
Maine. Maine Dept. Inland Fish. and Game, Fish Surv. Rept
(4), 238 p.

Dence., W. A. 1952. Establishment of white perch, Morone
americanus., in central New York. Copeia 1952(3):Tn--I-.

DeRoth 31 G. C. 1953. Some parasites from Maine freshwater
fishes. Trans. Amer. Microscopical Soc. LXXII(l).

Dorfman, D. and J. Westman. 1970. Responses of some anadro-
mous fishes to varied oxygen concentrations and increased
temperatures. New Jersey Water Resources Research Insti-
tute, Rutgers University, Research Project partial completion
and termination Report. OWRR Project B-012-N.J., 76 p.

Dovel, W. L. 1971. Fish eggs and larvae of the upper Chesa-
peake Bay. Natural Resources Inst., U. of Md., Spec. Rept.
(4):iii+ 71.

'Everhart, W. H. 1958. Fishes of Maine. Maine Dept. of
Inland Fish. and Game, Augusta, Maine. 94 p.
Foster, F. J. 1919. WhitesKerch notes and methods of prop-
agation. Trans. Amer. Fi Soc. 48(3):160-S.

Appendix 15
152

Goode, G. B. 1884. The fisheries and fishery industries of
the United States. Section I. Natural history of useful
aquatic animals. Wash., D. C., Gvt. Prtg. Off. xxxiv+ 895.

1888. American fishes. A popular treatise
upon game and food fishes of North America with especial
reference to habits and methods of capture. Standard Book
Co.3% N. Y., N. Y. 496 p.

Hergenrader, G. L., and Q. P. Bliss. 1971. The white perch
in Nebraska. Trans. Amer. Fish. Soc. 100(4):734-8.

Hildebrand, S. F., and W. C. Schroeder. 1928. Fishes of
Chesapeake Bay. Bull. U. S. Bur. Fish. 43, Part 1(1927):
1-366.

Hover, E. E. 1948. Preliminary biological survey of some
New Hampshire Lakes. New Hampshire Fish and Game Dept.,
Surv. Rept. (1) :

Hunter, G. W. 1942. Studies on the parasites of fresh-water
fishes of Connecticut. Conn. St. Geol. and Natural Hist.
Surv., Bull. (63).

Johnson, R. K. 1972. Production and distribution of fish
eggs and larvae in the Chesapeake and Delaware Canal.
Final Rept. Phila. Dist., Corps of Eng., U. S. Army, Con-
tract DACW 61-71-C-00621, ii+ 143.

King, W. 1947. Important food and game fishes of North
Carolina. Dept. Cons. and Dev., Div. Game and Inl. Fish.,
Raleigh, N. C., 54 p.

Lagler, K. F. 1961. Freshwater Fisheries Biology. William
C. Brown Dubuque, Iowa xii+ 421.

Larsen, A. 1954. First record of the white perch (Morone
americana) in Lake Erie. Copeia 1954 (2):154.

Linton., E. 1901. Parasites of fishes of the Woods Hole
region. Bull. U. S. Fish. Comm. (1899):405 492.

McCabe, B. C. 1944-5. Fisheries report for lakes of central
Massachusetts. Mass. Div. Fish. and Game., Boston.

1953. Fisheries report for lakes and ponds of
__N-orth_7Ce'_ntra1 Massachusetts. (19SO). Mass. Div. Fish. and
Game.

McErlean, A. J., and H. J. Brinkley. 1971. Temperature tol-.
erance and thyroid activity of the white perch Roccus
(=Morone americanus. J. Fish. Biol. 2(4):97-il4.

Appendix 15
153

Mansueti, R. J. 1961. Movements, reproduction, and mortality
of the white perch, Roccus americanus, in the Patuxent River
estuary, Maryland. CH-es. Sci. 2(3-4T:142-205.

1964. Eggs, larvae, and young of the*white
perch, Ro s americanus, with comments on its ecology in
the estuary. Ches. Sc1_. S(I-2):3-45.

and A. J. Mansueti. 1955. White perch eggs
and larvaF-studied in lab. Maryland Tidewater News 12(7):
1-3.

Meldrin'. J. W. and J. J. Gift. 1971. Temperature preference,
avoidance and shock experiments with estuarine fishes.
Ichthyological Assoc. Bull. (7), iii+ 75 p.

Meyer, M. C. 1954. The large animal parasites of the fresh-
water fishes of Maine. Maine Dept. Inland Fish. and Game.,
Management Div. Bull. (1):

Meyers, C. D. 1967. Final report on fish mortality investi-
gations in Chesapeake Bay and tributaries June 1964 to
September 1967. Natural Resources Inst., U. of Md., Ref.
No. 67-113, 133 p.

Millerl, L. W. 1963. Growth, reproduction and'food habits of
the white perch, Roccus americanus (Gmelin), in the Delaware
River estuary. U_.__o=e1., M.S.-Thesis, v+ 62.

Morgan, R. P., II, R. F. Fleming, V. J. Rasin, Jr., and D. R.
Heinle. 1973. Sublethal effects of Baltimore Harbor on
the white perch Morone americana and the hogchoker,
Trinectes maculitus. 7li-es. Sci. 1"4(l):17-27.

V and V. J. Rasin, Jr. 1973. Hydrographic and ecolog-
1-c-aT effects of enlargement of the Chesapeake and Delaware
Canal. Appendix X. Effects of salinity and temperature on
the development of eggs and'larvae of striped bass and white
perch. Natural Resources Inst., U. of Md.V Ref. 73-109D
37 p.

.0 . and L. A. Noe 1973. Hydrographic
an-T-ecological effects of enlargement of the Chesapeake and
Delaware Canal. Appendix XI. Effects of suspended sediments
on the development of eggs and larvae of striped bass and
white perch. Natural Resources Inst., U. of Md., Ref. 73-
1100 21 p.
;fand G. B. Gray.
1973a.-Ilydrographi-ca'nd ecological fects of enlargement
of the Chesapeake and Delaware Canal. Appendix XIII.
Effects of water quality in C and D Canal region on the
survival of eggs and larvae of striped bass and white
perch. Natural Resources Inst., U. of.Md., Ref. 73-112,
17 p.

Appendix 15
154

Morgan, R. P., II, R.E. Ulanowicz, V. J. Rasin, Jr., L. A.
Noe, and G. B. Gray. 1973. Hydrographic and ecological
effects of enlargement of the Chesapeake and Delaware
Canal. Appendix XII. Effects of water movement on eggs
and larvae of striped bass and white perch. Natural
Resources Inst., U. of Md., Ref. No. 73-111, 28 p.

North Carolina Wildlife Resources Commission. 1962. Some
North Carolina freshwater fishes. North Carolina Wildl.
Resources Comm., Raleigh, N. C., 46 p.

Radcliff, L., and W. W. Welsh. 1917. Notes on a collection
of fishes from the head of Chesapeake Bay. Proc. of the
Biol. Soc. of Washington. 30:35-42.

Raney, E. C. 1965. Some pond fishes of New York. Informa-
tion Leaflet, N. Y. State Cons. Dept., Div. Cons. Educ.
16 p.

Rehwoldt, R., G. Bida, and B. Nerrie. 1971. Acute toxicity
of copper, nickel, and zinc ions to some Hudson River fish
species. Bull. Environ. Contamination and Technology 6(5):
44S-8.

Reid., W. F., Jr. 1972. Utilization of the crayfish,
Orconectes limosus, as forage by white perch (Morone
americana) in a Maine lake. Trans. Amer. Fish. Soc.
101(4):608-12.

Richards, W. J. 1960. The life history, habits and ecology
of the white perch, Roccus americanus (Gmelin) in Cross
Lake, New York, M.S. Thesis, State Univ., College of For-
estry, Syracuse, N. Y., 113 p.

Rinaldo, R. G. 1971. Analysis of Morone saxatilis and
Morone americanus spawning and nursery areas in the York-
Pamunkey River, Virginia, M.S. Thesis, College of William
and Mary, vii+ 56.

Schubel, J. R., and C. R. Wong. 1973. The effect of sus-
pended sediment-on the hatching success of Perca flavescens
(yellow perch), Morone americana (white perch), Morone
saxatilis (striped bass), and Alosa pseudoharengus alewife)
eggs. Chesapeake Bay Institute, Johns Hopkins Univ., Ref.
73-3,

Schwartz, F. 1960. The perches. Maryland Conservationist
37(2):20-3.

Scott, W. B., and W. J. Christie. 1963. The invasion of the
lower Great Lakes by the white perch, Roccus americanus,
(Gmelin). J. Fish. Res. Bd., Canada 20(5):1189-95.

Appendix 15
155

SheriS A. N. and G. Power. 1968. Reproduction of white
perch, Roccus americanus, in the Bay of Quinte, Lake
Ontario. J. ish. Res. Bd. Canada. 25(10):2225-2231.

Smith* B. A. 1971. The fishes of four low-salinity tidal
tributaries of the Delaware River estuary. M.S. Thesis,
Cornell Univ.,, viii+ 304.

Stroud, R. H. 19S2. Management of warm-water fish popula-
tions in Massachusetts lakes, ponds, and reservoirs.
Trans. 17th N. A. Wildl. Conf., Wildl. Mgt. Inst., Wash.,
D. C.

1955a. Fisheries re port for some central, eastern,
anT-western Massachusetts lakes, ponds, and reservoirs
(1951-1952). Mass. Div. Fish. and Game.

and H. Bitzer. 1955b. Harvests and management of
warm-water fish populations in Massachusetts lakes, ponds,
and reservoirs. Prog. Fish-Cult. 17(2):Sl-63.

Taub, S. H.. 1966. Some aspects of the life history of the
white perchI Roccus americanus (Gmelin), in Quabbin Reser-
voir, Massachusetts. M.S. T is$ U. of Mass. vii+ 63.

ThoitsP C. F., III. and J. W. Mullan. 1958. A compendium
of the life history and ecology of the white perch, Morone
americana (Gmelin). Mass. Div. of Fish. and Game., Fish.
Bull. (ZT), 19 P.

Thorp, L. H. 1942. A fishery survey of important Connecticut
lakes. Connecticut State Geol. and Natural Hist. Surv.,
Bull. (63), 339 p.

Titcomb., J. W. 1910. Fish culture practices in the United
States Bureau of Fisheries. Bull. U. S. Bur. Fish. 28
(Part 2):699-757.

Tsai., C. F. 1970. Changes in fish populations and migration
in relation to increased sewage in Little Patuxent River,
Maryland. Ches. Sci. 11(l):34-41.

Wallace, D. C. 1971. Age, growth, ye.ar-class strength, and
survival rates of the white perch, Morone americana (Gmelin)
in the Delaware River in the vicinity of Artificial Island.
Ches. Sci. 12(4):2-50218.

Wang, J. C. S. 1971. A report on fishes taken in the Chesa-
peake and Delaware Canal and contiguous waters, p. 47-158,
1 fig., 15 tables, 46 appendix tables, In Ichthyological
Associates 1971. An ecological study ZoT the Delaware -
River in tAe vicinity of Artificial Island. Prog. Rept.,
Jan. to Dec. (1970), Part 2, 158 p.

Appendix 15
156

Webster, D. 1942. Food progression in young white perch.
Morone americana (Gmelin) from Bantam Lake, Connecticut.
T-rans. Amer. Fis-,b. Soc. (1942):136-44.

Whitworth, W. R.0 P. L. Berrien, and W. T. Keller. 1968.
Fresh-water fishes of Connecticut. State Geol. and Natural
Hist. Surv., Conn., Bull. (101):vi+ 134.

Woolcotts W. S. 1962. Intraspecific variation in the white
perch, Roccus americanus (Gmelin). Ches. Sci. 3(2):94-113.

Zitko, V., B. J. Finlayson, D. J. Wildish, J. M. Anderson,
and A. C. Kohler. 1971. Methylmercury in fresh-water and
marine fishes in New Brunswick, in the Bay of Fundy and on
the Nova Scotia banks. J. Fish. Res. Bd. Canada 28(9):
1285-91.

14-

Appendix 15
157

Category: Fish

Common Name: Spot

Inventory Prepared by: Linda L. Hudson and Jerry D. Hardy, Jr.
Department of Natural Resources
University of Maryland
Solomons, MaTyland

Classification

Class: Osteichthyes
Order: Perciformes
Family: Sciaenidae
Species: Leiostomus xanthurus (Lacepede)
Subspecies: None curi:-ently recognized.
Synonyms: Mugil obliquus Mitchill, 1815
Sciaena multotasciata Le Sueur, 1821
LeiosFomus riumeralis Cuvier and Valenciennes,
183T-
Other common names: Spot, Norfolk spot, flat croaker,
silver gudgeon, goody, Lafayette, chub, roach, jimmy,
spot croaker, oldwife (Dawson, 1958).

Distribution

Known range:. Coastal waters from Massachusetts Bay to Bay
of Campeche, Mexico (Bigelow.and Schroeder, 1953; Springer
and Bullis, 1956).

Distribution in Chesapeake Bay: Found throughout the area
(Hildebrand and Schroeder, 1928).

Areas of active reproduction: Moderately deep offshore
oceanic waters (Hildebrand and Schroeder, 1928; Dawson,
1958).

Occurrence in other areas: Inshore when not actively
spawning.

Population

Structure: A sex ratio of 50 females to 61 males has been
reported (Thomas, 1971).

Densities: Large yearly fluctuations apparently occur in
population densities (Thomas, 1971).

Reproduction

Method: External fertilization.

Appendix 15
.158

Reproduction (Continued)

Season and conditions: In Chesapeake Bay region November
to February, but mainly December and January (Hildebrand
and Cable, 1931); in South Carolina October to March,
peak December and January (Dawson, 1958); on Gulf Coast
October through March (Gunter, 194S; Pearson, 1928).

Fecundity: 70,000 to 90,000 (Dawson, 1958), with several
sizes of ova present in the ovary simultaneously
(Hildebrand and Cable, 1931).

Life Stages

Stages of life cycle: Egg, larva, juvenile, adult.

Early stages:

Physical appearance: Eggs undescribed. Hatching length
unknown. Smallest specimen described 1.5 mm. In lar-
vae of this size, yolk absorbed; mouth well developed,
very oblique; peritoneum dark; sometimes a row of dark
chromatophores along venter posterior to anus, and
another mid-laterally; few scattered chromatophores
on head. At 4.0 mm, urostyle usually oblique, caudal
rays developing, finfold still prominent. At 7.0 mm,
dorsal and anal rays developing, pectoral and ventral
fins forming, dark peritoneum still visible, a dark
chromatophore slightly in advance of anal origin, and
pigment spots in row mid-ventrally. At 15 mm, dark
peritoneum no longer visible. In juveniles at 20 mm,
dorsal outline convex., margin of caudal concave. At
25 mm., body proportionately deeper, pigmentation no-
ticeably.increased. At 30 mm, preopercular spines
absent; lateral line and scales well developed; lower
parts..silvery; body with dark chromatophores which
extend onto fins; sides usu *ally with row of dark
blotches; back sometimes with faint saddlelike
blotches. At 50 mm, form and color adultlike
(Hildebrand and Cable, 1931). Sundararaj (1960)
has described juveniles in which the scales are
visible at ca 22 mm.

Development: Growth rate varies considerably. For
example, Welsh and Breder (1923) recorded a total
length of 80 - 100 mm at 1 year, 170 - 220 mm, at 2
years, and 240 - 290 mm, at 3 years. Pacheco (1957)
obtained an average of ca 196 mm at the end of the
-first year and 247.9 mm at the end of the 2nd year.

Behavior: "Fry" (larvae?) found throughout the water
column, but are most abundant on the bottom; from
February to April, schools of young occur along shore,

Appendix 15
159

Behavior (Continued)

particularly in protected coves and around breakwaters
and jetties; later on, fish about 25 mm. long and longer
are abundant in vegetation; "young" ascend brackish-
water ditches to fresh water in spring and early summer;
immature fish remain in channels in shallow water or,
sometimes, over shallow-water grass flats throughout
winter., except during extremely severe cold snaps.
Apparently only immature fish move northward as far
as Massachusetts (the northern limit of the range),
making the trip in fall (Hildebrand and Cable, 1931;
Daiber and Smith., 1970).

Adult stage

Physical appearance: First dorsal triangular and with
10 spines, 2nd dorsal with 1 spine and 30 to 34 rays.
.Caudal concave. Pectorals pointed. Body bluish-grey
with golden reflections above, silvery below, and with
12 to 15 oblique yellowish cross bars. A conspicuous
black spot behind upper corner of each gill opening.
Fins yellowish or dusky (Bigelow and Schroeder, 1953).
Maximum length 330 mm. (Sundararaj, 1960).

Development: Spot apparently reach maturity in two
years. In the Chesapeake Bay region, the minimum size
at maturity is about 214 mm, on the Gulf Coast, 170 mm
(Hildebrand and Schroeder, 1928; Pearson, 1929).

Behavior: A schooling species. In late September and
October, migrate from Chesapeake Bay to North Carolina
to spawn (Hildebrand and Cable, 1931; Pacheco, 1962a).

Ecology
ITa-U-1tat (Physical/chemical)

Classification: Estuarinet marine, and fresh-water.

Salinity range: 0 to 60 o/oo (Massmann, 1954; Tagatz,
1968; Hedgpeth, 1967).
Temperature: 5 to 36.70C (Dawson, 1958; Hildebrand and
Cable, 1931).

Dissolved oxygen: Thus fa r, recorded in a range of 3.8
to 10.8 ppm (Thomas, 1971).
Benthic composition: "Young" in low salinity water over
bottom of thick loose mud (Reid, 1955).

Appendix 15
160

Food Requirements

Food: A benthic feeder (Thomas, 1971). Worms, crustaceans,
ostracods, copepods, mysids, amphipods, isopods, decapods,
shrimp, mollusks, echinoderms, fish, mites, insect larvae,
and plants (Dawson, 1958). Roelofs (1954) found that, in
"young", the diet consisted of 50% copepods and 25% anne-
lids. Hildebrand and Cable (1931) found that, up to a
size of 25 mm, the food consists wholly of small crusta-
ceans (principally copepods), but that, beyond that size,
young ingested plant fragments and sand. Plant material
may constitute up to 70% (by volume) of the stomach con-
tent; generally about 30% of the volume of the stomach
content consists of copepods (Thomas, 1971).

Consumers

Natural predators and parasites: Predators include sharks
(Dawson, 1958) and striped bass (Hollis, 1952), as well
as, to a very slight degree,_other game fish (Knapp,
1950). Worms occur in the gut (Hargis, 1957; Huizinga
and Haley, 1962; Korathe, 1955a, 1955b) and parasitic
copepods on the gills (Dawson, 1958).

Man: Man consumes large quantities of spot, for example,
up to 8,000,000 pounds per year in Virginia (Pacheco,
1962b).

'Influence of Toxins

Biocides: Lowe (1964, 1967) has studied the effects of
sublethal concentrations of toxaphene and prolonged
exposure to Sevin.

Radionuclides: Baptist (1966) studied the uptake of mixed
fission products on spot.

Bibliography

Baptist, J. P. 1966. Uptake of mixed fission products by
marine fishes. Trans. @mer. Fish. Soc. 95(2):145-52.

Bigelow, H. B., and W. C. Schroeder. 1953. Fishes of the
Gulf of Maine. Bull. U. S. Bur. Fish. 53(74):vii +S77.

Daiber, F. C., and R. W. Smith. 1970. An analysis of fish
populations in the Delaware Bay area. Ann. Dingell-Johnson
Rept., 1969-1970, Project F-13-R-12, 52 p.
Dawson, C. E. 1958. A study of the biology and life history'
of the spot 11 Leiostomus xanthurus Lacepede, with special
reference to South CaFo-lina. CoFtrib. Bears Bluff Lab.
(28), 48 p.

,Appendix 15
161

Gunter, G. 1945. Studies on marine fishes of Texas. Publ.
Inst. Mar. Sci. Texas l(l):9-190.

Hargis, W. J., Jr. 1957. The host specific 'ity of monogenetic
trematodes. Expt. Parasitology 6:610-25.

Hedgpeth, J. W. 1967. Ecological aspects of the Laguna Madre,
a hypersaline estuary, p. 408-19, In G. H. Lauff, editor.
Estuaries. Amer. Assoc. AdvancemeFF Sci. Publ. (83).

Hildebrand,, S. F. and L. E. Cable. 1931. Development and
life history of fourteen teleostean fishes from Beaufort,
N. C. Bull. U. S. Bur. Fish. XLVI (1930)'-383-488.

and W. C. Schroeder. 1928.' Fishes of Chesapeake
--Na-y. Buii. U. S. Bur. Fish. 43(Part 1), 366 p.

Hollis, E. H. 1952. Variations in the feeding habits of the
striped bass,, Roccus saxatilis (Walbaum), in Chesapeake Bay.
ogr.
Bingham Ocean ol 1. 14(TT-111-131.
Huizinga, H. W. and A. J. Haley. 1962. Occurrence of the
acanthocephalan parasite, Telorentis tenuicornis, in the
spot., Leiostomus [email protected],-i-n--CHes-ape-a-ke--Bay. Ches. Sci.
3 (1) : 37--TT-.

Knapp, F. T. 1950. Menhaden utilization in relation to the
conservation of the Texas Gulf Coast. Trans. Amer. Fish.
Soc. 79:137-44.

Koratha, K. H. 1955a. Studies on the monogenetic trematodes
of the Texas Coast - I. Results of a survey of marine
fishes at Port Aransas, with a review of Monogenea reported
from the Gulf of Mexico and notes on euryhalinity, host
specificity, and relationship of the Remora and the Cobia.
Publ. Init. Mar. Sci. Texas 4(l):233-49.

. 1955b. Studies on the monogenetic trematodes
of the Texas Coast - II. Descriptions of species from marine
fishes of Port Aransas. Bull. Inst. Mar. Sci. Texas 4(l):
253-73.

Lowe., J. 1,. 1964. Chronic exposure of spot 11 Leiostomus
xanthurus, to sublethal concentrati,ons of toxaphene in
awater. Trans. Amer. Fish. Soc. 93(4):396-9.

1967. Effects of prolonged exposure to Sevin on
an estuarine fish, Leiostomus xanthurus. Bull. Environ.
Contam. Toxical 2:147-55.

Massmann., W. H. 1954. Marine fishes in fresh and brackish
waters of Virginia rivers. Ecology 35(l):75-87.

Appendix 15
162

Nicholst J. T., and C. M. Breder, Jr. 1927. The marine
fishes of New York and southern New England. Zoologica
(New York) 9(l), 192 p.

PachecoP A. L. 1957. The length and age composition of
spot, Leiostomus xanthurus in the pound-net fishery of
lower Chesapea Bay. M7. Thesis, College of William
and Mary, 34 p.

1962a. Movements of spot, Leiostomus
xanthurus, in the lower Chesapeake Bay. ches! Sc1_. 3(4):

1962b. Age and growth of spot in lower
Chesapeake Bay, with notes on distribution and abundance
of-juveniles in the York River system. Ches. Sci. 3(l):
18-28.

PearsonX J. C. 1929. Natural history and conservation of
redfish and other commercial sciaenids on the 'Texas Coast.
Bull. U. S. Bur. Fish. 44:129-214.

Reid,, G. K., Jr. 195S. A summer study of the biology and
ecology of East Bay, Texas. Part II. The fish fauna of
East Bay, the Gulf Beach, and summary. Texas J. Sci. 7(4):
430-53.

Springer, S., and H. R. Bullis, Jr. 1956. Collections by
the OREGON in the Gulf of Mexico. U. S. Fish and Wildl.
Serv.1. Spec. Sci. Rept. Fisheries (196), 134 p.

Sundararaj, B. 1. 1960. Age and growth of the spot,
Leiostomus xanthurus Lacepede. Tulane Studies in Zool.
8(2):41-67.

Tagatz, M. E. 1968. Fishes of the St. Johns River, Florida.
Quart. J. Fla. Acad. Sci. 30(l):25-50.

Thomas, D. L. 1971. An ecological study of the Delaware
River in the vicinity of Artificial Island. Progress
Report for the period January - December, 1970. Part III.
The early life history and ecology of six species of drum
(Sciaenidae) in the lower Delaware River, a brackish-tida.1
estuary. Ichthyological Assoc. Bull. (3),'xvi+ 247.

Townsendt B. C., Jr. 19S6. A@study of the spot Leiostomus
xanthurus Lacepede, in Alligator Harbor, Florida. M.S.
Thesis,- Florida State Univ. 43 p.

Welsh, W. W. and C. M. Bredert Jr. 1923. Contributions to
the life histories of Sciaenidae of the eastern United
States coast. Bull. U. S. Bur. Fish. 39:141-201.

Appendix 15
163

Category: Fish

Common Name: Northern puffer

Inventory Prepared by: Linda L. Hudson and Jerry D. Hardy, Jr.
Department of Natural Resources
University of Maryland
Solomons, Maryland

Classification

Class: Osteichthyes
Order: Tetraodontiformes
Family: Tetraodontidae
Species: Sphoeroides maculatus (Bloch and Schneider)
Subspecies: None currently recognized
Synonyms: Tetraodon hispidis var. maculatus, Bloch and
Schn r ;_1=
Tetraodon turgidis,' Mitchill, 1815
Sphaeroides maculatus, Fraser-Brunner., 1943
Other common names: Futter,, swelitish, swell toad, sea
squab, balloonfish, bellowfish, globefish.

Distribution

Known range: Atlantic coast of North America from Bay of
Fundy, Canada, to Flagler County, Florida (Bigelow and
Schroeder, 1953; Shipp and Yerger, 1969a).

Distribution in Chesapeake Bay: North at least to Love
Point, Maryland (Hildebrand and Schroeder, 1928).

Areas of active reproduction: Shoal waters close inshore
(Bigelow and Schroeder, 1953).

Occurrence in other areas: A typically inshore species,
usually not found in water over 20 meters deep or more
than a mile or two from land. May run up into nearly
fresh water (Hildebrand and Schroeder, 1928; Shipp and
Yerger, 1969a).

Population

Reproduction

Method: External fertilization.

Seasons and conditions: Spawning begins in mid-May in
Chesapeake Bay. In Massachusetts, it begins somewhat
later (early June) and continues through summer
(Bigelow and Schroeder, 1953).

Appendix 15
164

Reproduction (Continued)

Fecundity: In a 268-mm specimen, about 176,000 eggs
(Bigelow and Schroeder, 1953).

Life Stages

Stages of life cycle: Egg, larva, juvenile, adult.

Early stages

Physical appearance: Eggs demersal, adhesive, trans-
parent, spherical; diame'ter 0.85 to 0.91 mm (average
0.874 mm); chorion finely reticulated; perivitelline
space narrow; yolk with numerous oil globules forming
clusters 0.34-mm wide. Hatching length, about 2.4 mm.
At hatching, pectorals formed; minute tubercles over
most of body; red, orange, yellow and black chroma-
tophores scattered over body; iris and anterior part
of yolk sac with purple chromatophores. By age of
one day, red chromatophores reduced, orange and yellow
more prominent. Mouth open at two days. At this age,
green pigment forming, especially in iris; a prominant
chrome-yellow spot on tail; dorsal pigment limited to
a few black chromatophores on head. At 7.35 to 7.80
mm fins formed, young essentially adult-like in appear-
ance (Welsh and Breder, 1922; Bigelow and Schroeder,
19S3; Hildebrand and Schroeder, 1928).
Development: Incubation takes about 112 hrs at 19.50C
(Welsh and Breder, 1922); 3h to S days at about 200C
(Bigelow and Schroeder, 1928).

Adult stage

Physical appearance: Dorsal 8, anal 7, pectoral 15-17.
Body heavy anteriorly, tapering to a noticeably slender
caudal peduncle; depth 3 times in length. Mouth small
and lacking teeth. Eyes near top of head. No ventral
.fins, caudal fin weakly rounded, but with angular cor-
ners. Parts of body covered with small close-set prick-
les. Dark green, ashy, or dusky above; sides with'6 to
8 vertical bars posterior to pectorals; belly white; in
mature specimens, dorsal and lateral surfaces with tiny
jet-black spots. Maximum length about 356 mm'. (Bigelow
and Schroeder, 1953; Shipp and Yerger, 1969b).

Development: Welsh and Breder (1922) noted that a 140-mm
male was mature. Shipp and Yerger (1969b) mention
"mature specimens" 70-mm long.

Appendix 15
165

Adult stage (Continued)

Behavior: Sometimes runs into estuaries having low
salinity; may make seasonal inshore-offshore move-
.ments in areas north of Cfiesapeake Bay (Bigelow and
Schroeder, 1953).

Ecology
Tra-6-1-tat (Physical/chemical)

Classification: Estuarine, coastal marine.

Depth: Not much beyond 20 meters (Bigelow and Schroeder,
1953).

Food Requirements

Food: Primarily crabs, shrimp, isopods, and amphipods;
also mollusks, annelids, barnacles, sea urchins, and
seaweed. Young feed on copepods as well as crustacean
and molluscan larvae (Bigelow and Schroeder, 19S3; Welsh
and Breder, 1922; Linton, 1901).

Consumers

Natural predators and parasites: No natural predators are
known. Linton (1901) listed the following kinds of para-
sites: Acanthocephala, cestodes and trematodes.

Man: The puffer is consumed by man, but only in limited
numbers. Popular in Virginia.

Influence of Toxins

Biocides: Eisler and Edmunds (1966) studied the effects of
endrin on blood and biochemistry of puffers. Johnson
(1968) reported a lethal concentration of 0.0031 ppm
based on 96 hrs exposure. Eisler and Weinstein (1967)
and Eisler (1967, 1970) commented on mortalities and
physiological and behavioral changes resulting from
exposure to methoxychlor and methyl parathion, and
presented toxicity levels on seven organochlorine and
six organophosphorus insecticides. End 'rin was found
to be most toxic, methyl parathion least toxic.

Bibliography
Bigelow, H..B., and W. C. Schroeder. 19S3. Fishes of the
Gulf of Maine. U. S. Fish and Wildl. Serv.0 Fish. Bull.
53(74) :vii+ 577.

Eisler, R. 1967. Tissue changes in puffers exposed to
methoxychlor and miethyl parathion. U. S. Bur. Sports
Fish. Wildl,, Tech. Paper (17), IS p.

Appendix 15
166

Eisler, R. 1970. Acute toxicities of organochlorine and
organophosphorus insecticides to estuarine fishes. U. S.
Bur. Sports Fish. & Wildl., Tech. Paper (46), 12 p.

and P. H. Edmunds. 1966. Effects of endrin on blood
an& tissue chemistry of a marine fish. Trans. Amer. Fish.
Soc. 95:153-9.

and M. P. Weinstein. 1967. Changes in metal compo-
sition of the quahaug clam, Mercenaria mercenaria, after
exposure to insecticides. Ches. Sci. 8(4):253-8.

Hildebrand., S. F., and W. C. Schroeder. 1928. Fishes of
Chesapeake Bay. Bull. U. S. Bur. Fish. 43(Part 1), 366 p.

Johnson, D. W. 1968. Pesticides and fishes - a review of
selected literature. Trans. Amer. Fish. Soc. 97(4):398-
424.

Linton, E. 1901. Parasites of fishes in the Woods Hole
region. U. S. Fish. Comm. Bull. (1899):405-92.

Shipp, R. L., and R. W. Yerger. 1969a. Status, characters,
and distribution of the northern and southern puffers of
the genus Sphoeroides. Copeia 1969:425-532.

, and . 1969b. A new puffer fish, Sphoeroides
parvis, from the western Gulf of Mexico, with a key to
species of Sphoeroides from the Atlantic and Gulf Coast
species of Sphoeroides from the Atlantic and Gulf Coasts
of the United States. Proc. Biol. Soc. Wash. 82:477-88.

Welsh, W. W., and C. M. Breder, Jr. 1922. A contribution to
the life history of the puffer, Sphoeroides maculatus
(Schneider) . Zoologica, (New York) 2(12) :261-76.

Appendix 15
167

Category: Reptile

Common Name: Snapping Turtle

Inventory Prepared by: Herbert S. Harris, Jr and Jerry D.
Hardy, Jr.
Natural Resources Institute
University of Maryland
Solomons, Maryland

Classification

Class: Reptilia
Order: Chelonia
Family: Chelydridae
Subfamily: Chelydrinae
Species: Chelydra serpentina serpentina Linnaeus
Subspecies: serpeH-tina (North erica and Mexico)
osceol-a-7eninsular Florida)
rossignoni (Guatemala to Costa Rick)
acutiFo-stris (Panama to Ecuador)
Synonyms: Chelydra lacertina Schweigger, 1812
do longl--- 1831
Testu caucra- Shaw,
Chely( emargi-na-ta Agassiz, 1857
Other common names: common snapping turtle

Distribution

Known range: Southern Canada to Ecuador. Range of the
subspecies serpentina southern Canada through Mexico
(Conant, 1958; Carr, 1952).

Distribution in Chesapeake Bay: Found in appropriate
.habitats throughout the region (McCauley, 1945; Harris,
1969).

Areas of active reproduction: Mating takes place in bays,
tributaries, ponds, creeks, and ditches. Eggs are
deposited on land at various distances from water
(Carr, 1952).

Occurrence in other areas: Found in almost any aquatic
situation,, but prefer habitats-with soft muddy bottom
(Carr, 1952).

Population

Structure: The sex ratio is approximately 1:1. In two
different studies ratios of males to females were 27 to
28 and 74 to 77 (Mosiman and Bider, 1960; Lagler and
Applegate, 1943).

APPendix 15
168

Population (Continued)

Densities and totals: Lagler (1943a) estimated approxi-
mately 2 snapping turtles per acre of surface in a
Michigan lake. Hammer (1969) estimated a total of
2,415 adult turtles in a South Dakota marsh, with an
average of 1 turtle per 2 acre area. The species
congregates in large numbers to hibernate (Carr, 1952).

Reproduction

Method: Internal fertili-zation (Carr, 1952).

Season and conditions: Mating may take place from late
April to November, but eggs are apparently deposited
only between May and October. Deposition occurs on
land (Carr, 1952).

Fecundity: Eleven to 87 eggs with averages reported as
25 and 37 (Carr, 1952; Hammer, 1969; Yntema., 1970).
Bleakney,(1957) reported that a 362 mm specimen con-
tained 83 eggs. Larger females apparently produce
larger eggs (Yntema, 1970).

Life Stages

Stages of life cycle: Eggs, juveniles, adults.

Early life stages

Physical appearance: The eggs are round and vary from 23
to 32 mm in diameter with an average of 26.8 mm (Yntema,
1970). Juveniles approximately 30 mm long at hatching
and similar to adults (ConantV 1958).

Development: Incubation period normally about 60 to 90
days. The young usually remain in the nest no more
than 10 to 15 days, although both eggs and juveniles
have been known to overwinter in the nest (Carr, 1952;
Ernst, 1966; Hammer, 1969; Toner, 1933; Yntema, 1.960).

Survival: Gibbons (1970) reported an average growth rate
of 32 mm per year through the first 6 years. Survival
of young is affected by predators and climate. In a
marsh in South Dakota, 59% of the nests were destroyed
by skunks, minks, and raccoons. In the same area,
hatchlings emerged from less than 20% of the undis-
turbed nests (Hammer, 1969). Ernst (1966) pointed
out that severe drought conditions may hamper hatchling
success. Yntema (1970) found that snapping turtle
embryos did not survive sustained temperatures of
340C or more.

Appendix 1.5
169

Adult stage

Physical appearance: A large dark-brown or black turtle
with a long tail. The shell has three keels and is
serrate posteriorly. The plastron is very small and
cross-shaped (Conant, 1958). Yntema (1970) and Lagler
and Applegate (1943) give average lengths of about 265
mm.

Development: Sexual maturity is attained at a carapace
length of about 200 mm. (Mosiman and Bider, 1960).

Behavior: The snapping turtle is primarily restricted to
the aquatic environment, although Gibbons (1970) col-
lected a number of individuals on land using pitfall
traps. Klimstra (1951) reported a maximum distance
from water of 610 yards. Hammer (1969) reported that
there was "little movement" in this species; but re-
corded a movement of 3.75 miles in 3 years in one
specimen, and pointed out that one female moved 2.11
miles in ten days. Carr (1952) mentioned that snapping
turtles congregate in large numbers to hibernate.
Langlois (1964) found hibernating individuals beneath
damp soil. Breeding behavior has been described by
Hamilton (1940) and Pell (1941). McBride (196,3) re-
ported on apparent defense behavior in a large male.

Ecology
F=aItat (Physical/chemical)

Classification: Fresh and brackish water., also terrestrial.

Salinity range: Fresh to "brackish" water (Neill, 1958).
Temperature range: Upper lethal temperature 38 to 410C
(Baldwin, 1925; Boyer, 1965).

Food Requirements

Food: Omnivorous: principal food - fish and aquatic plants
(Lagler, 1943a; Alexander, 1943). Other animal food in-
cludes other reptiles (snakes and young alligators),
frogs, tadpoles, salamanders, birds, small mammals, and
a variety of invertebrates, as well as carrion. Plant
food includes algae, duckweed, waterlilies, and skunk
cabbage (Carr, 1952; Lagler, 1943b; Brown, 1969). B 'ush
(1959) recorded a population which consumed 75% (by
weight) of crayfish (Cambarus sp.) and 2S% (by weight)
of tree frogs (Hyla versicolor). He pointed out that
the amount of pT-ant material eaten varied from 36.2 to
80.2%. Pell (1941) believed the species was carnivorous
in spring and largely herbivorous in summer. Coulter
(1957) found that snapping turtles destroyed 10 to 13%
of the duckling population in a South Dakota marsh.

Appendix 15
1-7-0--

Food Requirements (Continued)

Feeding: Opportunistic (Conant, 1958).

Consumers

Natural predators and parasites: Predators include bull-
frogs, fish, reptiles, crows, hawks, skunks, minks, and
raccoons (Brown, 1969; Conant, 1958; Korschgen and
Baskett, 1963). The snapping turtle is parasitized by
nematodes., trematodes, and leeches (Ernst et al., 1969;
Brown, 1969).

Man: Both the eggs and flesh are consumed by man (Brown,
1969; Conant, 1958).

Non-nutritional Role

The shell is utilized by various species of algae (Dixon,
1961).

Influence of Toxins

Meeks (1968) reported high accumulations of DDT in the fat,
liver, and testes of snapping turtles 15 months after
ap.plication.

Bibliography

Alexander, M. M. 1943 Food habits of the snapping turtle
in Connecticut. J. Wildl. Mgt. 7(3):278-282.

Baldwin, F. M. 1925. The relation of body to environmental
temperatures in turtles, Chrysemys marginata belli (Gray)
and Chelydra,serpentina (Linn.). Bioi. BUTI _T97.T32-4S.
Bleakney,'S. 1957. A snapping turtle ,Chelydra serpentina
ser entina, containing eighty-three eggs. copeia 195 =-.3.

Boyer, D. R. 1965. Ecology of the basking habit of turtles.
Ecology 46:99-118.

Brown, R. 1969. Snapping turtles. Herpetology 3(2):9-12.

Bush F. M. 1959. Foods of some Kentucky herptiles.
Herpetologica 15:73-7.

Carr, A. 19S2. Handbook of turtles. The turtles of the
United States, Canada, and Baja California. Comstock
Publ. Assoc., Ithaca, N. Y.', 542 p.
Conant, R. 1958. A field guide to reptiles and amphibians
of the United States and Canada east of the 100th Meridian.
Houghton Mifflin Co., Boston, Mass. 366 p.

Appendix 15
171

Coulter, M. W. 1957. Predation by snapping turtles upon
aquatic birds in Maine marshes. J. Wildl. Mgt. 21(l):
17-21.

Dixon, J. R. 1961. Epizoophytic. algae on some turtles of
Texas and Mexico. Texas J. Sci. 12:36-8.

Ernst., C. H. 1966. Overwintering of hatchling Ch 1 dra
serpentina in southeastern Pennsylvania. Bull
[Terp. soc. 14(Z) :8-9.

Ernst, J. V.* T. B. Stewart, J. R. Sampson, and G. T. Fincher.
1969. Eimeria chelydrae n. sp. (Protozoa:Eimeriidae) from
the snaFp-lng turtle,, ChFlydra serpentina. Bull. Wildl. dis.
Ass. 22:410-11.

Gibbons, J. W. 1970. Terrestrial activity and the population
dynamics of aquatic turtles. Amer. Midl. Nat. 83(2):404-14.

Hamilton, W. J., Jr. 1940. Observations on the reproductive
behavior of the snapping turtle. Copeia 1940(2):124-6.

Hammer, D. A. 1969. Parameters of a marsh snapping turtle
population, Lacreek Refuge, South Dakota. J. Wildl. Mgt.
33:995-1005.

Harris., H. S., Jr. 1969. Distributional survey, Maryland
and the District of Columbia. Bull. Maryland Herp. Soc.
5(4):67-161.

Klimstra, W. D. 1951. Notes on'late summer snapping turtle
movements. Herpetologica 7:140.

Korschgen, L., Jr., and T. S. Baskett. 1963. Food of im-
poundment-and stream-dwelling bullfrogs in Missouri.
Herpetologica 19(2):89-99.

-Lagler, K. F. 1943a. Methods of collecting freshwater
turtles. Copeia 1943(l):21-5.

1943b. Food habits and econo mic. relations of
the turtlF oE Michigan with 'special reference to game man-
agement. Amer. Midl. Nat. 29:257-312.

1. and V. Applegate. 1943. Relationship between
the le-n-gffff and weight in the snapping turtle, Chelydra
serpent@na Linnaeus. Amer. Nat. 77:476-8.

Langlois, T. 1964. Amphibians and reptiles of the Erie
Island. Ohio J. Sci. 64(l):11-25.

McBride, B. 1963. Observations on a newly captured snapping
turtle, Chelydra serpentina serpentina. Bull. Phil. Herp.
Soc.

ADDendix 15
172

McCauley, R. H. 1945. The reptiles of Maryland and the
District of Columbia. Hagerstown, Md.

Meeks) R. L. 1968. The accumulation of 36C1 ring-labeled
DDT in a freshwater marsh. J. Wildl. Mgt. 32(2):376-98.

Mosimann, J. E.,, and J. R. Bider. 1960.. Variation, sexual
dimorphism, and maturity in a Quebec population of the
common snapping turtle, Chelydra serpentina. Canada J.
Zool. 38(l):19-38.

Neill, W. T. 1958. The occurrence of amphibians and rep-
tiles in saltwater areas, and a bibliography. Bull. Mar.
Sci. Gulf Carib. 8(l):1-97.

Pell., S. M. 1941. Notes on the habits of the common snap-
ping turtle, Chelydra serpentina (Linn.) in central New
York. M.S. Thesis, Cornell Un-1v., 85 p.

Toner, G. C. 1933. Overwinter eggs of the snapping turtle.
Copeia 1933(4):221-2.

Yntema, C. L. 1970. Observations on females and eggs of the
common snapping turtle, Chelydra serpentina. Amer. Midl.
Nat. 87(l):68-76.

Appendix 15
173

Categor Reptile

Common Name: Diamondback terrapin

Inventory Prepared by: Herbert S. Harris, Jr., and Jerry D.
Hardy, Jr.
Department of Natural Resources
University of Maryland -0
Solomons, Maryland

Classification

Class: Reptilia
Order: Chelonia
Family: Testudinidae
Subfamily: Enydinae
Species: Malaclemys terrapin terrapin Schoepff
Subspecies: terrapin (Cape Cod to Cape Hatteras)
centrii-ta (Cape Hatteras to northern Florida)
tequesta (east coast of Florida)
rhizo-pYo-rarum (the Florida Keys)
macrospilota (west coast of Florida)
pileata (Florida and Louisiana)
littoralis (Texas and possibly Mexico)
Synonyms: Malaclemys terrapin terrapin Lindholm, 1929
Testudo concentrica TFa_w_=,02
Testu ocellata =inkl 1807
F
Em s macrocephala Gray, 1844
s
al-aclemys tuEe-rculifora Gray, 1844
Other common names: Northern di-a-m-o-n-c1back terrapin

Distribution

Known range: Cape Cod, Massachusetts to Mexico. The sub-
species terrapin ranges from Cape Cod to Cape Hatteras,
North Carolina (Conantf 1958).

Distribution in Chesapeake Bay: Found throughout the re-
gion (McCauley, 194S; Harris, 1969).

Area of active reproduction: Copulation takes place in
the water (Carr, 19S2).

Occurrence in other areas: Coastal marshes, tide flats,
coves, estuaries, al 'ong inner edges of barrier beaches;
generally any sheltered and unpolluted body of salt or
brackish water (Conant, 1958), also probably in tidal-
fresh water (Warden., 1920).
P2pulation -W
Structure: Hildebrand (1932) reported a sex ratio of 1
male to 5.9 females in a captive breeding population.

Appendix 15
174

Structure (Continued)

He also stated that a ratio of 1 male to 8 females would
ensure fertility in his captive breeding program.

Dynamics

Trends and fluctuations: Overexploitation has caused
serious fluctuations in population density. In 1891,
the total Maryland catch was estimated at 89,150
pounds; in 1920, the total catch was 823 pounds and
the species was apparently close to extinction in the
area (McCauley, 1945).

Affecting factors: Diamond-back terrapins are killed by
man and several other predators. Pollution and destruc-
tion of the wetlands habitat are serious threats to the
species.

Reproduction

Method: Internal fertilization, promiscuous; females
produce fertile eggs for three or four years from a
single mating (Hay, 1907; Hildebrand and Hatsel, 1926).

Season and conditions: Mating takes place in spring;
eggs are deposited on sandy beaches 'from May to August
(Hay, 1904; Hildebrand and Hatsel, 1926; Schwartz,
1967).

.Fe cundity: 5 to 18 (Hay, 1904; Truitt, 1939).

Life Stages

Stages of life cycle: Egg, juvenile, adult.

Early stages

Physical appearance: Eggs oblong; average size 31.1 x
21.2 mm; pinkish-white when deposited; shell fragile,
easily dented. Hatchlings are about 30 mm long and
similar to adults (McCauley, 1945).

Development: Hatching occurs (in various subspecies) in
61-90 days (Cunningham, 1939; Hay, 1904; Reid, 1960).
Allen and Littleford (1955) observed a growth rate of
31.28 mm in the first year and 27.70 mm in the second
year. Hay (1904) stated that the young grow an inch
a year during the first 5 years.

Survival: Hay (1904) states that the hatchlings spend
the first winter buried in marshes. When they emerge,,
they are especially vulnerable to predation.

Appendix 15
175

Adult stage
Physical appearance: Body color light-grey on brown;
plastron yellow to greenish-grey. Carapace with a
central keel; concentric grooves and ridges on all
large dorsal scutes (Conant, 1958; Schwartz, 1967).
Maximum length of Chesapeake Bay female, plastron
8.1 in. (206 mm); male about 2/3 size of female
(Carr, 19S2).

Development: Maturity is reached at an age of 5 years
(Hildebrand and Hatsel, 1926).

Survival: Both Hildebrand and Hatsel (1926) and Truitt
(1939) point out that adult diamondbacks have no impor-
tant enemies except man. Crab traps cause death of
many in Va. (Editor).

Behavior: An aquatic species which frequently bask out
of water. In winter, hibernates at bottoms of ponds
and rivers (Hay, 1904; Reid, 1960; Schwartz, 1967).

Ecology
Habitat (Physical/chemical)

Classification: Salt, brackish, or, rarely, tidal-fresh
water (Conant, 1958; Worden, 1920).

Salinity range: Possibly fresh water (Worden, 1920) to
full-strength sea water (Neill, 1958).

Temperature range: Upper lethal temperature for eggs
95OF; development of eggs temporarily stopped at SSOF
(Qunningham, 1959).

Food Requirements

Food: Omnivorous (Reid, 1960). Primarily.crustaceans and
molluscs, also insects and plant material; in captivity
eat cut-up fish (Carr, 1952).
Time: Feed most actively while the tide is in (T ruitt,
1939).

Consumers

Natural predators: Fish, birds, rats, muskrats, skunks,,
raccoons (Hildebrand and Hatsel, 1926; Schwartz, 1967;
Truitt, 1939).

Man: During the early part of the 20 th century, the diamond-
back terrapin was heavily exploited by man; since that
time, it has been less actively sought and the species
is now making a strong comeback (Conant, 1958; Reid, 1960).

Appendix 15
176

Man (Continued)

A number of authors have described culture methods for
the diamondback terrapin (Hildebrand and Hatsel, 1926;
Hildebrand, 1929, 1932; Truitt, 1939; Hildebrand and
Prytherch, 1947).

Influence of Toxins

In 1960, the senior author observed a number of diamondback
terrapins in Baltimore Harbor which were dying after being
heavily coated with oil and grease.

Bibliography

Allen, J. F., and R. H. Littleford. 1955. Observations on
the feeding, habits and growth of immature diamondback
terrapins. Herpetologica 11:77-80.

Carr, A. 1952. Handbook of turtles. The turtles of the
United States, Canada, and Baja California. Comstock
Publ. Assoc., Ithaca, N. Y. 542 p.

Conant, R. 1958. A field guide to reptiles and amphibians
of the United States and Canada east of the 100th meridian.
Houghton Mifflin Co,', Boston, Mass. 366 p.

Cunningham, B. 1939. Effect of temperature upon the devel-
opment rate of the embryo of the diamondback terrapin
(Malaclemys centrata Lat.). Amer. Nat. 73:381-4.

Harris, H. S., Jr. 1969. Distributional survey, Maryland
and the District of Columbia. Bull. Md. Herp. Soc. 5(4):
67-161.

Hay, &. P. 1904. A revision of Malaclemys, a genus of
turtles. Bull. U. S. Bur. Fish. Z4(19UST:1-20.

Hildebrand, S. F. 1929. Review of experiment on artificial
culture of diamondback terrapins. Bull. U. S. Bur. Fish.
45:25-70.

. 1932. Growth of diamondback terrapins - size
attained. sex ratio and longevity. Zoologica (New York)
9(15):551-563.

and C. Hatsel. 1926. Diamondback terrapin
CuFt-ure at Beaufort, North Carolina. U. S. Dept. Comm.,
Bur. Fish., Econ. Circ. 60-, 20 p.

and Herbert F. Pryth6rch. 1947. Diamondback
terrapin culture. U. S. Dept. Interior, Fish. Leaflet
(216), 6 p.

Appendix 15
177

McCauley, R. H. 1945. The reptiles of Maryland and the
District of Columbia. Hagerstown, Maryland.

Neill, W. T. 1958. The occurrence of amphibians and
reptiles in salt-water areas, and a bibliography. Bull,
Mar. Sci. Gulf and Carib. 8(l):1-97.

Reid, G. K. 1960. A turtle of taste. Nat. Hist. 69(10): 4
22-7.

Schwartz, F. J. 1967. Maryland turtles. Univ. Md., Nat.
Resources Inst. Educ. Ser. (79), 38 p.
Truitt, R. V. 193@. Our water resources and their conser-
vation. Ches. Biol. Lab., Contrib. No. (27), 103 p.

Worden, D. B. 1820. Description statistique, historique et
politique des Etats-Unis de l'Amerique septemtrionale.
ParisJ, Chez Rey et Gravier 1820, Sv.

Appendix 15
178

Common Name: Whistling Swan Scientific Name: Olor columbianus

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality:

Fall migration: Oct. 15-25 to Nov. 20-30, with peak
falling between Oct. 25 and Nov. 20. Spring migration:
Mar. 1-10 to Apr. 20-30; with peak falling between Mar. 10
and Apr. 5 (Stewart, 1962). Usually migrates in flocks of
5 to 200 or more.

Preferred Habitat

Generally restricted to fairly extensive areas of open
estuarine waters not more than 5 ft.. deep; locally will occa-
sionally inhabit saltwater estuarine bays.
The 1955-58 Fish & Wildl. Serv. average ecological
distribution of wintering population reads as follows:
brackish estuarine bays - 76%, salt estuarine bays - 9%,
fresh estuarine bays - 8%, slightly brackish estuarine
bays - 6%, coastal impoundment-bay complex - 1%, fresh &
brackish estuarine bay marshes - t%.
Fall & spring migration: occur regularly in open shallow
tidewater areas of fresh & slightly brackish estuarine bays
(Stewart, 1962).

Nesting

' Large bulky mass of sticks, moss, grass, rubbish and
other materials, lined lightly with feathers or down, placed
on ground near water; in artic regions usually on a small
island in a secluded area or a bank marsh close to pond
(Bailey, 1913).

Food Habits

Rarely dives but obtains food by extending head under
water and sieving. Primarily aquatic plants, also: grasses,
sedges, eelgrass, wild celery and foxtail grass (the latter
3 being preferred during winter as Back Bay, Va.); grain,
tadpoles, frogs, small fish, worms, insects and shellfish
(Bailey, 1913). Recently began feeding in wheat fields in
Md., Del., N.C., and Va.

Reproduction

Mate for life when 3 years old, begins nesting at ages
4 to 6 (Banko and Mackay, 1964).

Season: Late May and early June; incubation period
about 32 days.
Appendix 15.
.179

Clutch Size: 4-7, usually 4; 1 brood per season (Banko
and Smith, 1964).

Fledging Period: 50 to 60 days (Reilly, 1968).

Reproductive Success: Between 2 and 3 survive to fly
(Banko and Mackay, 1964).

Growth Rate
Age at 'maturity: 4-6 years (Banko and Mackay, 1964).
Longevity: Swans live long lives, some living as long
as@70 years in captivity (Brooks, 1922). Record in nature
19 years.

Mortality

Predation: Coyote (minor cause)

Natural: Storms destructive to nests and young: early
winter storms "ground" large numbers. Aquatic vegetation
apparently much reduced in estuaries in recent decades. High
mortality from visceral gout, lead poisoning, heart worm and
aspergillosia.

Man-made: Natives in artic region, limited hunting season
in Western U.S. and minor illegal harvest elsewhere.

Mortality rate: Unknown, probably under 30% after age 1.

Competition

Ducks and geese also eat aquatic vegetation and grain crops.

Abundance

In area: Large numbers migrate through, and winter in,
upper Ches. Bay region - F.&W.S. 1953-58 wintering populations
given as 17,000 in 1958 to 71,600 in 1955. Atlantic Flyway
population in 1974 was 64,200, up 12% from 1973 (Ferguson and
Smith, 1974).

Over total range: Breed in Arctic islands or ponds north
of Arctic Circle from n. Alaska to Baffin Is., s. to barren
grounds of Canada, Alaskan Peninsula and St. Lawrence Islands.
Maximum density ca. 1 pr./sq. m. Winters - mainly Ches. Bay,
Back Bayand Currituck Sound N.C., Del., Texas and in n.Calif.,
Nev. and Utah (Banko and Mackay, 1964).

Known reasons for decline or increases: Protected by
law (except Arctic nTt-ives allowed to take them. This has
resulted in steady increases. All-time high Christmas Bird
Count was 37,670 set at Sacramento, Calif. in 1973 (Monroe,
1973). Use of upland food habitats may reduce winter mortality
caused by lack of nutrition.

Appendix 15
180

Bailey, H. H. 1913. The Birds of Virginia. 362 p.

Banko., W. E. and R. H. Mackay. 1964. Our native swans.
In: Waterfowl Tomorrow, Linduska, J. P. (ed.), Fish
and Wildl. Serv., pp. 155-164.

Bent, A. C. 1925. Life Histories of North American Wild
Fowl, 11. 314 p.

Ferguson, E. L. and M. M. Smith. 1974. Results of the 1974
mid-winter waterfowl survey in the Atlantic States.
Bur-Sport Fish. and Wildl., 3 p.

Monroe, B. L., Jr. 1973. Summary of all-time highest counts
of individuals for Canada and the U. S. American Birds
27:541-547.

Reilly, E. M., Jr. 1968. The Audubon Illustrated Handbook
of American Birds. McGraw-Hill, New York, N. Y. 524 pp.

Stewart, R. E. 1962. Waterfowl Populations in the Upper
Chesapeake Region. Fish Wildl. Serv., Spec. Sci.
Rep. Wildl. No. 65.

Appendix 15
181

Common Name: Canada Goose Scientific Name: Branta canadensis

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality

Migrate Feb. - Apr. with peak Mar. 10 to Apr. 10; Sept.
Dec. with peak Oct. 15 to Nov. 5 (Stewart, 1962).

Preferred Habitat

water shallow enough to allow easy feeding. Also deeper
water near open fields where grasses & other vegetation offer
sufficient food.

Nesting

Variety of situations: usually hollow in ground or mound
of grasses, reeds, etc. lined with feathers, occasionally high
on cliffs., rarely in old crow and eagle nests. Now frequently
on artificial platforms in United States. Nest usually well-
made structureS well-hidden.

Food Habits

Great variety of aquatic plants & roots, grain and grasses;
also small vertebrates and invertebrates, including frogs,
toads, fish, worms, crustaceans and mollusks. Feed either on
shore or bring food up from bottom by thrusting head and neck
under water. Probably most of winter feeding is now in grain
fields.

Reproduction

Pair for life, young usually mate before migration of second
or third year.
Season: Apr. - June.

Clutch: 4 to 10, usually 5 or 6; 1 brood/season (Bent,
1925)*

Incubation: 28 to 30 days by female only (Bent, 1925).
Fledging Period: Young leave nest shortly after hatch-- 41-
ing, unable to__F1_y__Tor 50 days or more-(Reilly, 1968).

Reproductive sticcess: Nests 64% successful in southern
end of range, up to 87T-Tin Arctic (Hansen and Nelson, 1964).

Growth Rate

Age at maturity: Mate in 2nd to 4th year.

Appendix 15
182

Longevity: Up to 33 year's (Kortright,, 1943).

Mor-tality

Predation: Crows, raccoons and skunks in southern end
jaegers, gulls and foxes in Arctic. Predation
little in Arctic except when lemmings are low (Hansen and
Nelson, 1964).

Natural: Parasitic diseases, botulism, storms., over-
crowded nesting grounds.

Man-caused: Shooting, unstable levels in impoundments;
spills and lea2r poisoning.

mortality rate: Unknown, likely under 30% after first
year in most popul tions.

Competition

Competes with other geese' including brant and swans,
also plant-eating ducks and coots.

Abundance

In area: Some bred in captivity in Ches. Bay area, esp..
at Patuxent Refuge. Has also bred at Chincoteague NWR.

Over total range: Most widely distributed of water-
fowl; from Atlantic to Pacific Oceans, and from Gulf of Mexico
to Arctic Coast. Formerly bred from n. North America south
to c. Calif., Mont 1, se. Canada; now breeds south to St.
Marks, Fla. Altho@gh all-time CBC high was set in 1950 at
Sacramento, Calif., species is still increasing. Winter
survey in 1974 showed Canada Goose up to 19.3% over 10-yr.
average in Atlantic Flyway (Ferguson and -Smith, 1974).

Known reasons for increase: Benefits have come from
increased numbers oF refuges affd greater food supplies from
farm fields.

Literature Cited

Bent, A. C. 1925. Life Histories of North American Wild
Fowl, 11. 314 p.
Ferguson, E. L. and M. M. Smith. 1974. Results of the 1974
mid-winter waterfowl survey in the Atlantic Flyway
states. Bur. Sport Fish. and Wildl., 3 p.

Appendix
183

Hansen, H. A. and H. K. Nelson. 1964. Honkers large and
small. Pages 109-124 in J. P. Linduska, ed. Waterfowl
Tomorrow. Fish and WiMl. Serv.

Kortright, F. H. 1942. The ducks, geese and swans of North
America. Amer. Wildl. Inst., Wash., D. C., 476 p.

Reilly, E. M., Jr. 1968. The Audubon Illustrated Handbook
of American Birds. McGraw Hillf New York, N. Y.@ 524 p.

Stewart, R. E. 1962. Waterfowl Populations in the Upper
Chesapeake Region. Fish & Wildl. Serv., Spec. Sci.
Rep. Wildl. No. 65. 208 p.

ADD-endix 15
184

Common Name: Black Duck Scientific Name: Anas rubripes

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality

Sept. 10-20 to Dec. 1-10, peak around Oct. 20 - Nov. 25;
Feb. 15-25 to Apr. 15-25, peak around Feb. 25 - Mar. 25.
Breeds throughout area in suitable salt marshes (Stewart,
1962).

Preferred Habitat

Bottomlands, swamps, freshwater impoundments of coastal
plain, estuarine and coastal bays and marshe�_.

Nesting

Nearly 60% in wooded areas, 18t on duck blinds, 16% in
marshes and 5% in cultivated areas and borders.

Food Habits

Consumes about 3 times as much animal food as the mallard
does. Examination of 390 stomachs showed plants 76%, animals
24%. Plants (t) included pondweeds 32, grasses 11, sedges 11,
smartweed S. seeds of burr reed) watershield, water lilies and
coontail 9. miscellaneous 13. Animal percentages were molluscs
12., crustaceans 89 insects 2. fishes 1. miscellaneous 1.
During summer and autumn, food is 90% vegetable (Kortright,
1942).

Reproduction

Season: Breeding: Mar. - mid-Aug. Apr. - June peak;
peak egg dates: last Apr. - first May, hatching mainly May -
June.

Clutch: In Kent I., Md. study, average clutch (360
clutcH-e-sT-Ueclined from 10.9 early in season to 7.5 near end;
max. 14.

Incubation: Average 26.2 days (Sl clutches).
Fledging Period: Eight to nine weeks.

Reproductive success: Of 574 nests, 38% hatched one or
more eggs, 11.51 were ff-es-erted and 50% were destroyed (34% by
crows). In Md., 5.1 young were produced per nest.

Appendix- 1-5
185

Growth Rate

Age at maturity: One year, but not all breed during
first year.

Longevity: Up to 10 yrs. (Kortright, 1942).

Mortality

Predation: Mainly on eggs by fish crow in Md.; less by
common crow and raccoon.

Natural: Storms, botulism, parasitic diseases. Tidal
flooding caused 30% of nest desertion in Md. (Stotts and
Davis, 1960).

Man-caused: Hunting, pesticides, and lead poisoning; loss
of nesting habitat probably most important. Humans collected
eggs in 1955 in Md. (Stotts and Davis, 1960).
MortalitZ rate From hatching to flying, 9.2%; of adult
females 50 few surviving to age 4 or 5 (Stotts and Davis,
1960).

Competition

With Canvasback, Mallard and other waterfowl for aquatic
,plants and upland grains.

Abundance

In area: Breeds s. to se. Va. and upper James. Up to
21 pairs per acre on some islands in Eastern Bay, Md. (Addy,
1964).

Over total range: Breeds from Hudson Bay east to n.
Lab. -&-NM. s. to Great Lakes & e. N.C.
Winters from Ont., Quebec, Prince Edward I. and
Nfld., south to Gulf coast and Fla. Atlantic Flyway popula-
tion now at lowest point in 20 years (Ferguson and Smith,
1974). All-time CBC high was 36,000 at Oceanville, N.J. in
1966; 3.5 times the 1974 high.

Known reasons for increase or decline: Species is now
one of the 70-point ducks, which allows only 2 per day to be
taken. However, numbers in Atlantic Flyway were down 10.5%
(to 246,700) from 1973,population, which still made it
second in duck numberst but only a third of the Canada Goose
population.

Literature Cited
Addy, C. E. 1964. Atlantic Flyway, 167-184. In: Linduska,
J. P. (ed.),, Waterfowl Tomorrow, Bur, Sport Fish.
Wildl.

---App-end-ix--l5
186

Kortright, F. H. 1942. The ducks, geese and swans of North
America. Amer. Wildl. Inst., Wash., D. C. 476 p.

Stewart, R. E. 1962. Waterfowl populations in the upper
Chesapeake Region. F. 4 Wildl. Serv., Spec. Sci. Rep.
Wildl. No. 65. 208 p.

Stotts$ V. D. and D. E. Davis. 1960. The black duck in the
Chesapeake Bay of Maryland: Breeding behavior and biol-
ogy. Chesapeake Sci. 1:127-154.

'Appendix 15
187

Common Name: 'Bufflehead Scientific Name: Bucephala albeola

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality

Fall migration: Oct. 20-30 to Dec. 10-20; peak: Nov. 1-
30.
Spring migration: Mar. 10-20 to Apr. 20-30; peak: Mar.
25-Apr. 15 (Stewart, 1962).
Late migrant both fall and spring;.usually travels in
flocks of 20 to 50 during peaks of migration (Reilly, 1968).

Preferred Habitat

Ponds, lakes and rivers; estuarine and inshore marine
waters in winter, and Great Lakes.

Nesting

Almost entirely dependent on holes made by flickers in
poplars, cottonwoods and Douglas fir in the boreal-montane
coniferous forest biome. Use of nest boxes is increasing
(Erskine, 1971).

Food Habits

Mainly insects on freshwater, crustaceans on saltwater.
Plant material may predominate in autumn (Erskine, 1971).
Overall - 80% animal, 20% vegetable (Cottam, 1939).

Reproduction

Season: Late April through July.

Clutch Size: 5-17., usually 5-11; 9 being most common
(dump-nesting T-Ossible in large clutches). Clutches started
Apr. 23 - May 31 in B.C. Largest clutches laid first wee@ in
May. Late clutches may be renestings (Erskine, 1971)..

Incubation Period: 28-33 days after last egg hatched,
usually between Z9-31-days (Erskine, 1971).

Fledging Period: 50-55 days (Erskine, 1971).

Reproductive success: Nest success averages 75-80%,
much higher than for i-round-nesting ducks. Hatching in
successful nests was 90% in B.C. Probably only 50% or less
of young survive to flight age (Erskine, .1971).

Appendix- -1-5-
188

Growth Rate

. Age at maturity: Breed at age 2, although less success-
fully-than older birds do (Erskine, 1971).

Longevity: 4 banded at Kent I., Md. lived from ll;i to
1331 yrs.

Mortality

Predation: Once preyed on by Peregrine Falcon (Kortright,
1942).

Natural: Summer storms may cause loss of young; fowl cholera,
1970 TL-573 =e, et. al., 1970).
Man-caused: Some shooting, grouped with ducks valued.at
25 points, thi only 4 may be legally shot in one day. Cutting
of nest trees possibly most detrimental. Oil spills are significant.

Mortality rate: 72% first year, 53t thereafter, calcu-
lated from banUing data. Annual adult mortality probably only
about 30% (Erskine, 1971).

Competition

Competes with goldeneyes and scaups for food in summer
and winter; with starlings, tree swallows, squirrels, and
goldeneyes for nests in parts of range (Erskine, 1971).

In area: Migrant and wintering flocks common in upper
Chesap--ea-g-e-region (Stewart, 1962). Population holding better
than any other duck, being 34.8% above 10-yr. average in
Atlantic Flyway (Ferguson and Smith, 1974).

Over total range: Breeding: from Hudson Bay to Alaska
& B.C # s. to Calif. (Reilly, 1968); probably 2/3 of total
popul@tion breeds in the interior of B.C. and Alberta
(Erskine, 1971).
Winter: Gulf Coast and Calif.; north to British
Columbia, Ontario and Nova,Scotia.

Known reasons for increase or decline: Recent increase
likely due to less hunting and natural predation.. It is also
largely unaffected by drouths. Coastal refuges and inland
reservoirs also help it. Permanent decline since 19th'cen-
tury largely due to loss of 100 x 800 mile "parklands" in w.
Canada.

Literature Cited

Cotfam, C. 1939. Food habits of North American diving
ducks. U. S. Dept. Agr. Bull. No. 643:1-139.

Append-i-x -15--
189

Erskine, A. J. Buffleheads. Canadian Wildl. Serv.
Monog. 4. 240 p.

Ferguson, E. L. and M. M. Smith. 1974. Results of the 1974
mid-winter waterfowl survey in the Atlantic flyway
states, 3 p.

Locke, L. N., V. Stotts, and G. Wolfhand. 1970. An outbreak
of fowl cholera in waterfowl on the Chesapeake Bay.
Wildl. Dis. 6: 404-7.

Reilly, E. M., Jr. 1968. The Audubon Illustrated Handbook
of American Birds. McGraw-Hill, New York, N. Y. 524 pp.

Stewart, R. E. 1962. Waterfowl populations in the upper
Chesapeake Region. F. & Wildl. Serv., Spec. Sci. Rep.
Wildl. No. 65. 208 p.

A,Ppendix--15
190

Common Name: Oldsquaw Scientific Name: Clangula hyemalis

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality

Oct. 20-30 to Dec. 10-20; peak: Nov. 5-Dec. S.
Mar. 1-10 to Apr. 20-30; peak: Mar. 15-Apr. 15.
(Stewart, 1962).

Preferred Habitat

Ponds on tundra in summer; Great Lakes, estuaries and
coastal waters in winter.

Nesting

Hollow lined with down from breast of femalef located on
ground of tundra of sub-Arctic regions (Bent, 1925).

Food Habits

In examination of 227 stomachs: crustaceans - 48%,
mollusks - 16%, insects - 11%, fishes - 10%, miscellaneous
animal food - 3%; grasses - 3.5%, pondweeds - 1.5%. mis-
cellaneous plant food - 7% (Cottam, 1939). Able to dive to
depths of 200 feet.

Reproduction

Season: May to July, occasionally as late as Aug.
Clutch size: As many as 17, usually 5 to 7; 1 brood/
season, with as many as 2 replacement sets (Bent, 1925).

Incubation period: 3h weeks, by female alone; male
stays close y until hatched.

Fledging-Period: Age at first flight unknown (Reilly,
1968).
Ruroductive success: Unknown, apparently low recently,
down Z9t on Atlantic FTyWay in 1974 from 1973.

Growth rate

Age at maturity: Around 2 years (Kortright, 1942).
LongevitV Unknown, possibly 15 years.

Appendix 15
191

Mortality

Predation: Dogs, foxes, jaegers, gulls, and coyotes
destroy eggs and young (Bent, 1925).

Natural: Storms during breeding season. Fowl cholera,
1970. (Locke, et. al., 1970).

Man-caused: Although not very tasty, many are still hunted
during duck season because of their quick flight which presents
a challenge. Bag limit is 7-10 per day (since this is a 10-pt.
duck), and season is over 3 months long; oil spills and gill nets.

Mortality: Unknown, probably currently high.

Competition

Competes with scoters, goldeneye and bufflehead for food.
Large blue crab population possibly detrimental.

Abundance

In-area: Common transient and winterresident along
coast and throughout brackish/salt estuarine bays of Chesapeake
region (Stewart, 1962).

Over total range: Circumpolar; breeds on all Arctic tundras
from Atlantic to Pacific s. along mountains into extreme n. B.C.;
winters s. to Calif. and Fla. (rarely), also Great Lakes. All-
time CBC high of 35,500 set on Lake Michigan in 1956. Atlantic
Flyway count was 7,900 in Jan., 1974; down 29% from 1973 (Ferguson
and Smith, 1974).

Reasons for increase or decline: Early decline due to large
kills by gill nets in Great Lakes. Dead hen found in Ware R.,
Va., 1972 had 6 lead shot in gizzard; 4 would probably kill this
species. Oil spills and fowl diseases also a factor.

Literature Cited

Bent, A. C. 1925. Life histories of North American wildfowl.
Part II. U. S. Nat. Mus. Bull. 130: 1-314.

Cottam, C. 1939. Food habits of North American diving ducks.
U. S. Dept. Agr. Bull. No. 643: 1-139.

Kortright, F. H. 1942. The ducks, geese and swans of North
America. Amer. Wildl. Inst., Wash., D. C. 476 p.

Locke, L. N., V. Stotts, and G. Wolfhand. 1970. An outbreak
of fowl cholera in waterfowl on the Chesapeake Bay. Journ.
Wildl. Dis. 6: 404-7.

Reilly, E. M., Jr. 1968. The Audubon Illustrated Handbook
of American Birds. McGraw-Hill, New York, N. Y. 524 pp.

Stewart, R. E. 1962. Waterfowl populations in the upper
Chesapeake Region. F. & Wildl. Serv., Spec. Sci. Rep. -
Wildl. No. 65. 208 p.

Appendix 15.
192

Common Name: Ruddy Duck Scientific Name: Oxyura jamaicensis

Prepared by: Marvin L. Wass
Virginia Institute of Marine Science
Gloucester Point, Virginia

Seasonality

Sept. 15-25 to Dec. 5-1S; peak: Oct. 25-Nov. 30.
Mar. 1-10 to May 10-20; peak: Mar. 1S-Apr. 10.
(Stewart, 1962).

Preferred Habitat

Freshwater ponds, lakes, marshes; enters marine waters
in winter (Reilly, 1968).

Nesting

Nests near prairie sloughs wherever vegetation provides
a thick cover; forms a basket-like structure of materials from
surrounding vegetation, cleverly matching it with environment;
built about 8 inches above water level and attached firmly to
reeds (Kortright, 1942).

Food Habits

Diet mostly vegetation, for which it dives to bottom.
Examination of 181 stomachs yielded: pondweeds - 30%, sedges -
18%, muskgrass - 4%. wildcelery - 2.5%, smartweeds - l.S%,
watermilfoils - 1%. grasses - 1%, miscellaneous plants and
gravel - 13%; animal content: insects - 22%. mollusks - 3%9
crustaceans - 1 S% miscellaneous - S% (Cottam, 1939)- Diet
mostly animal i@ brackish waters of Ches. Bay (Stewart, 1962).
Reproduction

Season: Apr. - Aug.

Clutch size: As many as 19 or 20, usually 6 to 9 or 10;
eggs are very large; Z broods may be raised per season
(Bent, 1925).

Incubation period: Unknown, probably around 30 days by
female alone, but contrary-to other ducks, male remains near
until young are fully grown.(Bent, 1925).
.V
Fledgling period: Age at first flight around 52-66 days
(Reilly, 196

Reproductive success: Unknown, probably near 6 per nest.

Growth rate

Age at maturity: I year (?) (Kortright'. 1942).

Appendix 15
193

Longevity: May live up to 20 years (Kortright, 1942).

Mortality

Predation: Foxes, dogs, coyotes, raccoons, mink; prob-
ably higher n for hole and Arctic nesting species.

Natural: Storms

Man--cau-sed: Lead poisoning, oil spills, chemicals, destruc
tion of wet lands, sport kill likely less than for-most other ducks.

Mortality rate: Unknown

Competition.

Apparently not great, food similar to that of Bufflehead,
but containing more plant material.

Abundance

In area: Migrant and winter resident along Ches. region;
common in many areas.

Total range: Breeds mainly in prairie states and prov-
inces from Nebr. to n. Sask. and from B.C. to Minn... rarely
on e. coast. Winters from B.C. to Guatemala, incl. most of
Mexico; and from N.J. to s. Fla.

Reasons for decline or increase: Increasing, only common
duck setting an all time high on a Christmas Bird Count in the
United States since 1968 (in 1971 and again in 1974). Atlantic.
Flyway population 281 above 10-yr. average in Jan., 1974
(Ferguson and Smith, 1974).

Literature Cited

Ferguson, E. L. and M. M. Smith. 1974. Results of the 1974
mid-winter waterfowl survey in the Atlantic States.
Bur. Sport Fish. and Wildl., 3 p.

Kortright, F. H. 1942. The ducks, geese and swans of North
America. Amer. Wildl. Inst., Wash., D. C., 476 p.

Reilly, E. M., Jr. 1968. The Audubon Illustrated Handbook
of American Birds. McGraw-Hill, New York., N. Y. S24 pp.

Stewart, R. E. 1962. Waterfowl Populations in the Upper
Chesapeake Region, Fish & Wildl. Serv., Spec. Sci.
-Rep. Wildl. No. 65.

Appendix 15
194

Common Name: Osprey Scientific Name: Pandion haliaetus

Prepared by: Donald W. Meritt
Center for Estuarine and Environmental Studies
Chesapeake Biological Laboratory
Solomonsf Maryland

Seasonality

In the Chesapeake Bay area, birds occur from March
through November (Stewart and Robbins, 1958). Main migration
occurs late March through early April, and mid-September
through early October. Some immatures start south as early
as late August (Henny and Van Velzen, 1972).

Preferred habitat

Along the Coast in bays, rivers, and estuaries. Inland
near lakes or rivers.

Nesting

Formerly in trees (Reese 1969), but adapt well to
available man-made structures (duckblinds, channel markers,
telephone poles); occasionally on the ground. Chesapeake
site selections are broken down as follows: trees (31.7%);
duck blinds (28.7%); channel markers (21.8%); other man-made
structures (17.8%) (Henny et al., 1974); often nesting in
loose colonies.-

Food habits

Diet made up almost entirely of fish: menhaden, eels,
killifish, hogchoker, and toadfish. Seldom, if ever, feeds
upon dead fish.

Reproduction

Season: Late March through late August (peak, late
April tgr-ough early July) (Stewart and Robbins, 1958).

Clutch size: 2-4; 1 clutch normally laid; relaying may
occur if eggs are removed or destroyed early in the season
(Reese, 1970).

Incubation period
: Bent (1938) and Ames (1964) give
incubation pe_r1`5-d-s-_oT Z8-33 days. Garber and Koplin (1972)
report California ospreys incubating as long as 38-43 days,
Thirty-eight day incubation periods have also been recorded
in Chesapeake populations (Reese, pers. comm.). Both sexes
are known to incubate (Garber an Koplin, 1972; Reese, pers.
comm.) with the male incubating about 30% of the time (Garber
and Koplin, 1972).

Appendix 15
195

Fledging period:, About 48-59 days (Reese, pers. comm.;
Statts and Henry, 1975).

Reproductive success: Number of birds fledged per
active accessible nest; . 4 to 1.16 (527 nests, Talbot Co.,
Md.Y 1963-69) (Reese, 1970); .87 to 1.43 (422 nests, Talbot
C0.0 Md. 1970-73) (Reese, pers. comm.); .43 to .81 (88 nests,
Queen Annes Co., Md. 1966-69) (Reese, 1970); .87 (20 nests,
Queen Annes Co., Md. 1973) (Reese, peTs. comm.); .73 to 1.2S
(86 nests, Choptank River Md. 1968-71) (Reese, 1972); 1.43
(28 nests, Choptank River, Md. 1973) (Reese, pers. comm.);
.45 to .98 (104 nests, Potomac River, Md. 1963, 1967-68)
(Reese, 1970); .70 (46 nests,, Potomac River, Md. 1970)
(Wiemeyer 1971); 1.6 (46 nests, Smith's Pt., Va. 1934
(Tyrrell, .9 1936).

Production rates required to maintain a stable popula-
tion are estimated at 1.22 - 1.30 young per active nest.
Maryland osprey populations are currently declining 2-3%
annually (Henny and Ogden, 1970). Preliminary 1974 data
indicate Va. nests increased to near 606; fledge rate near
1.2 (vs. .75 in 1972). Several nests fledged 4 young in
1974 whereas none did so before 1972. However, James R.
had no nests in 19741, following 5 years of complete hatching
failure. Nest on navigation aids are twice as successful
as other nests.

Growth rate

Age at maturity: At least 3 years. Although some birds
return to the nesting grounds and build nests as 2-yr olds,
no eggs are laid (Henny and Van Velzen, 1972).

Longevity: Band recoveries indicate ospreys live at
least 18 years (Henny and Wight, 1969).

Mortality

Predation: Adults have few problems with predators;
eggs and youH-g are more vulnerable, crows and rats have been
seen in the act of egg robbing, and raccoons, otters, snakes,
muskrats, diamond-backed terrapins, gulls, herons, owls, and
foxes are probable or potential predators (Reese, 1970).

Natural: Violent summer storms with heavy rain, high
winds d-n-a-T-Ides take a major toll of eggs and young (Reese,
1970); exposure to the sun is also known to cause nestling
mortality (Tyrrell, 1936).
Man-caused: The US. Coast Guard, through maintenance
to navigational aids, h@s caused substantial egg and nestling
losses (Reese, 1970); water-oriented recreational activities
disturb nesting ospreys and reduce egg hatchability and nest-
ling survival (Reese, 1970; Ames and Mersereau, 1964).

Appendix IS
196

Mortality Rate: 53.3% for the lst year; 19.6% for 2nd
througN_1 =t, for 29.6% overall (Henny and Wight, 1969).

Competition

Bald Eagles rob ospreys of fish but this is not a major
factor due to the small population of eagles in the Chesapeake
system.

Abundance

In area: 1450 + 30 pairs estimated in Chesapeake Bay
area TRenny et al., 1974).

Over total range: Cosmopolitan; American subspecies P.
h. carolinensis breeds from N. Alaska to Baja California a5d
97onFra, east Fo S. LabradorP Newfoundland, and south to
Florida. Winters from southern United States to South America
(Bureau of Sport Fisheries & Wildlife, 1973). Population
declining over most of the United States at a rate of 2-14%
annually with the exception of the Florida Bay population,
which is stable (Henny and Ogden, 1970).

Known reasons for increase or decline:. Major reason for
population declines in the U.S. is egg--T-ailure (Reese, 1970;
Ames and Mersereau, 1964; Kury, 1966); chlorinated hydrocar-
bons have been shown to cause thinning in eggshells which
could account for eggs being broken (Hickey and Anderson,
-1968; Porter and Wiemeyer, 1969; Wiemeyer and Porter, 1970).
Maryland osprey eggs have been shown to contain chlorinated
hydrocarbon concentrations of 3.0 microgrammes per milliliter
of total egg volume.(Ames, 1966).

Literature Cited

Ames, P. L. 1964. Notes on the breeding behavior of the
osprey. Atlantic Nat. 19:15-27.

1966. DDT residues in the eggs of the osprey
Northeastern United States and their relation to
nesting success. J. Appl. Ecol., 3 (Suppl.):87-97.

and G. S. Merser'eau. 1964. Some factors in the
-a-ed-ri-ne of the osprey in Connecticut. Auk 81:173-185.

Bent, A..C. 1937. Life histories of North American birds
of prey. Vol. II. U. S. Natl. Mus., Bull. 195:352-379.

Garber, D. P., and J. R. Koplin. 1972. Prolonged and bi-
sexual incubation by.California ospreys. Condor'. 74,
F No. 2. 201-2.

Appendix 15
197

Henny, C. J., M. M. Smith, and V. D. Stoots. 1974. The 1973
distribution and abundance of breeding ospreys in the
Chesapeake Bay. Chesapeake Scii 15(3): 125-133..

' and W. T. Van Velzen. 1972 . Migration patterns
and wintering localities of American ospreys. J. Wildl.
Mgmt. 36(4): 1133-1141.

, and J. C. Ogden. 1970. Estimated status of
osprey populations in the United States. J. Wildl. Mgmt.
34(l): 214-17.

and H. M. Wight. 1969. An endangered osprey
population: estimates of mortality and production. Auk
86(2): 188-198.

Hickey, J. J., and D. W. Anderson. 1968. Chlorinated hydro-
carbons and eggshell changes in raptorial and fish-eating
birds. Science 162 (3850): 271-273.

Kury, C. R. 1966. Osprey nesting survey. Wilson Bull.,
78: 470.

Porter, R. D., and S. N. Wiemeyer. 1969. Dieldrin and DDT:
Effects of sparrow hawk eggshells and reproduction.
Science 165, 199-200.

Reese, J. G. 1969. A Maryland osprey population 75 years
ago and today. Maryland Birdlife 25(4): 116-119.

1970. Reproduction in a Chesapeake Bay osprey
population. Auk 87(4) : 747-759.

. 1972. Osprey nesting success along the Choptank
River, Maryland. Chesapeake Sci. 13(3) : 233-235.

Stewart, R. E., and C. S. Robbins. 1958. Birds of Maryland
and the District of Columbia. U.S. Dept. of Int. Fish
and Wildl. Ser. No. 62.

Stotts, V. and Henry. 1975. The age of first flight for
young American ospreys. Wils. Bull. 87(2) : 277-8.

Tyrrell, W. B. 1936. The ospreys of Smith's Point, Virginia.
Auk 53: 261-268.

U.S. Bureau of Sport Fisheries and Wildlife. 1973. Threat-
ened Wildlife of the United States. Resource Publication
114.

Wiemeyer, S. N. 1971. Reproductive success of Potomac River
ospreys-1970. Chesapeake Sci. 12(4): 278-280.

, and R. D. Porter. 1970. DDE thins eggshells of
captive American kestrels. 'Nature 227, No. 5259, 737-738.

Appendix 15
.198

CHAPTER VI

ECOLOGY OF SELECTED CHESAPEAKE BAY COMMUNITIES

To complement information on species life histories,
presented in Chapter V, consideration is made here of
two of the more important biological communities.
The community concept recognizes that many of the
plants and animals in an aquatic environment are
dependent in various degrees on one another, and that
interrelationships between even microscopic life forms,
and other subtle environmental variables, may have
crucial effects on higher animals in the community.
Thus, in an effort to provide water resource managers
with a foundation for their decisions regarding human
activities which influence community stability, the
following was prepared by Dr. Forrest E. Payne of
the Smithsonian Institution.

STATUS OF KNOWLEDGE

Delineation of the various types of Chesapeake Bay
communities is a formidable task because an overall,
concrete community concept does not exist. It is
not unusual for one investigator to designate a
group of organisms living together as a community,
whereas another investigator will consider this same
group as either several distinct communities or
merely as a subdivision of an even larger community.
Scarcity of literature on estuarine community structure

Appendix 15
199

is another obstacle. A few studies on Chesapeake Bay
community structure have been conducted (e.g., Stone,
1963; Marsh, 1970; Boesch, 1971; Orth, 1971; and
Richardson, 1971), but they deal with communities
found only in limited Bay Regions, whereas information
on other Bay localities and other Bay communities is
practically nonexistent. A few more inclusive works
on general estuarine community structure and on
detailed descriptions of particular communities exist
(e.g., Allee, 1934; Day, 1951; Thorson, 1957; Carriker,
1967; Sanders, 1968; Remane and Schlieper, 1971).
Some information included in these publications can
be directly applied to Chesapeake Bay communities,
thereby increasing the knowledge base.

An attempt will be made in this chapter to describe
in detail the interactions between organisms that
compose the community and the interactions between
the community and its environment. A correspondent
of H. T. Odum, B. J. Copeland and E. A. McMahan
(1974) expressed the problems associated with a
study such as this when he stated:

What needs emphasis is that we have almost
none of the hard, detailed information
which is needed to intelligently manage
most of our shore areas. Written material
like this is likely to give would-be man-
agers the illusion that they know a whole
lot, and can now proceed with safely pre-
dictable results. It seems to me this
could lead to great damage. What these
managers really need is a brochure set-
ting out the complexity of the problems
to be faced, and pointing out the neces-
sity of making detailed local studies of e
each particular situation before making
drastic changes therein!

This chapter attempts to demonstrate the complexity
of the problem for water managers. The Zostera
marina (eelgrass) community and the Crassostrea
virginica (oyster) community will be discussed in
detail. The fish, bottom and plankton communities
will be reported in more generalized terms. Choice
of the communities studied in detail was not solely
because of economical importance but also for their
economical significance, trophic relationships, vul-
herability to stress and/or spatial distribution.

Appendix 15
200

Although the two communities are discussed rather
thoroughly, it must be emphasized that much of the
information utilized in their preparation was not
from research concerned with the Chesapeake ray.
Therefore, a water manager must not accept statements
verbatim but must conduct his own investigation in
the locality where a decision will be nothing more
than an educated guess; but if he attempts to utilize
all channels of available information, then the chances
of an unfavorable decision are greatly diminished.

CHESAPEAKE BAY COMMUNITY STRUCTURE

In Chapter III of this appendix the concepts of community
and "limiting factors" and the environmental parameters
that act as "limiting factors" were reviewed. It is
these basic ideas and parameters that are the foundation
of this report. Hopefully, it is understood that one
cannot deisgnate the boundaries of a Bay community as
one would a community of people. If a person says he
is from Baltimore, a specific geographical region is
brought to mind. However, mention of a specific Bay
community, e.g., the NepthL7s-Ogyrides-Retusa community,
may provide a different picture in the mind of a Maryland
investigator who usually thinks only in terms of upper
Bay communities than in the mind of a Virginia researcher
who usually considers only lower Bay communities. In
other words, managers must recognize that community
boundaries are not only indistinct, but often form a
continuum and also that "one" community can be dis-
tributed in many localities throughout the Bay.

This section will present the major ecological communities
found in the Chesapeake Bay. The basis of classification
.for these communities was given in the discussion of the
community concept, i.e., by physical habitat or by a
dominant structural feature. The use of energy flow,
as a means of classification, was not attempted at this
time. Copeland (1970) used this method for generalized
separation of estuarine system types. He based this
separation on the maj-or energy source factors of each
@W7 system. For example, the major energy source(s), of
a grass bottom is light, of a clam flat is circulation,
and of a marsh is (are) light and land runoff.

Appendix 15
201

The criteria necessary for the Chesapeake Bay classi-
fication scheme are demonstrated in Table 15-5. This
system is based on the division of the estuary into geo-
graphical divisions. Four of these divisions were first
designated by Day (1951) in his discussion of an ideal
estuary. Carriker (1967) added one other division': the
lower reaches of the estuary. Both investigators based
their division on salinity, water movement and substrate.
It must be emphasized that neither Carriker nor ray
intended these divisions to be precise boundaries, but
rather rough approximations. Carriker (1967) character-
ized the central regions of these divisions thusly:

1. "Head of estuary - where fresh water enters
the estuary from streams, and salinity during
high spring tides may reach a maximum of 5 ppt.
Currents and substrate vary broadly and are
dependent on the physiography of the region."

TABLE 15-5
CLASSIFICATION OF APPROXIMATE GEOGRAPHIC
DIVISIONS, SALINITY RANGES, TYPES, AND
DISTRIBUTION OF ORGANISMS IN ESTUARIES
(Carriker, 1967)

Venice system Ecological classification

Divisions Salinity 7ypes of organisms and approximate range of
of ranges distribution in estuary, relative to divisions
estuary % zones and salinities

River 0.5 limnetic limnetic

Head 0.5 - 5 oligobalinfit oligohaline

LWer Reaches 5 - 18 mesobaline aline
'ue
Middle Reaches 18 - 25 polybaline est ine

Lower Reaches 25 - 30 polyhaline

Pbuth 3D.-- 40 eubaline iohaline eurybaline migrants
IF marine marine

Appendix 15
202

2. "Upper reaches of estuary - muddy bottoms,
slow movement of water, and salinities from 5 to
18 ppt.11

3. "Middle reaches of estuary - sandy mud bottoms,
fairly fast movement of water, with salinities from
18 to 25 PPt."

4. "Lower reaches of estuary - sandy mud to
clear sand or gravel bottoms, fast movement of water,
and salinities from 25 to 30 Ppt."

5. "Mouth or inlet of estuary - clean sand,
,gravel, or rock bottom, very rapid flow of water,
with salinities above 30 ppt and depending on the
salinity of neritic water outside."

In addition to delineating geographical divisions.,
zones and salinity ranges of organisms in estuaries,
Carriker (1967) also demonstrated the approximate range
,of distribution of types of estuarine organisms in
relation to these criteria. The terminology Carriker
used in classifying estuarine organisms has been applied
in this review to Chesapeake Bay organisms. For example,
an oligohaline organism is one that generally does not
survive a salinity content greater than 5 PPt, whereas a
'true estuarine organism can survive in a range of about
0.5 PPt to 30 Ppt- "True" estuarine species have marine
affinities, but do not occur in the sea or in freshwater.
They have adapted to the estuarine environment and require
its conditions for their survival. Euryhaline organismss,
by definition, tolerate a wide range of salinities, i.e.,,
they can live in seawater and in salinities sometimes as
low as 5 PPt- On the contrary, stenohaline organisms do
not tolerate a wide salinity range, e.g., stenohaline
marine organisms are limited in their penetration into
estuaries by a salinity content no lower than 25 Ppt-
Migrant organisms are characterized as those organisms
that move in and out of a community and/or which only
spend a portion of their life in a bay. Distribution of
salinity zones in Chesapeake Bay is illustrated in Figurel5-16.
This scheme is arbit.rary and subject to change. Using
these definitions, salinity zones and divisions, an attempt
has been made to classify Chesapeake Bay communities.
4
It is not the intention of this report to present
a rigid classification of Chesapeake Bay communities
because it is not unusual for different communities to
overlap and form ecotone communities. Instead, a

An ecotone is the area of overlap between two more or
less diverse communities (Odum, 1959)

Appendix 15
203

C&D conol

&ALTIMORE

VKWY MAP

04.
WASHINGTON

0 q@-
C
0 ---Ca
011,
SALINITY
ZONES
11-00
I-Bay Mouth BM
2. PolyhalineP
3. MesobalineM
4.0figobaline0
5. fresh Water: EW

IUCHMOND
0

sme in mi.es

im 01

CHESAPSEAKE.
OLK BAY
7@i , @

FIGURE 15-16: SALINITY ZONES OF CHESAPEAKE BAY
From Boesch (unpublished).

Appendix 15
204

generalized scheme of community delineation by means of
salinity zones is given (Table 15-6).

The decision by which communities were chosen for
investigation was arbitrary. It may appear that a partic-
ular community was not important since it was not initially
chosen for further study. On the contrary, all Bay commu-
nities are important because of the complex interactions
between inhabiting organisms of a community and between
one community and another. It is our purpose to present as
complete a picture of certain Chesapeake Bay communities
as possible to enable an estuarine manager to make perti-
nent and timely decisions.

ZOSTERA COMMUNITY

The Zostera community derives its name from the domi-
nant species of a distinct assemblage of organisms. Re-
member that the dominant species is one way of naming a
community. In thig.case, Zostera (eelgrass) is
the dominant species. It is also the comptroller of the
energy flow among the species living in the community. A
water manager, therefore, must understand the natural his-
tory of eelgrass in order to appreciate the intricacies of
community relations.

One question a water manager will ask when he is faced
with a decision that could result in the removal of a
Zostera bed is: "Why is eelgrass important?" Orth (1971)
listed several reasons, both physico-chemical and bio-
logical:

(1) It provides a habitat for a wide variety
of microorganisms.

(2) It provides a substrate for epifauna.

(3) It is utilized as a nursery ground by fish.

_(4) It is a food source for ducks and brant.

(5) The organic detritus formed by Zostera, plus
the microorganisms absorbed on it, represent the main
energy source for animals living in the Zostera com-
-4; munity and for animals outside the community to which
detritus is transported.
(6) The plant physically acts as a stabilizing
factor for bottom sediments, which allows greater
faunal diversity.

(7) It plays a role in reducing turbidity and
erosion in coastal bays.

Appendix 15
205

TABLE 15-6
(D
WO COMMUNITY STRUCTURE BY SALINITY ZONE97IN CHESAPEAKE BAY

MOUTH MIDDLE and LOWER UPPER REACHES HEAD RIVER
REACHES
[UHALINE POLYHALINII ZONE MESOHALINE ZONE OLIGONALINE ZONE LIMNETIC ZONE
Benthk Aquatic plants, e.g. Zoatera Aquatic plants, *. 9 - Ruppla Aquatic plants, e.g. RugWa, Aquatic plants, e.g. P_mjRmggjjin0
MyrI&ohXlhM Zennitheill
lnt*rtldal (beach) Ilenthic Benthic Benthic Benthic
Sand Mud Sand, Mud Sand Mud
Sand-mud combinations Sand-mud combinations Sand-mud combinations
Epif ouna Epifouno-on or upon solid Eplfauno-on or upon solid Eplfauna-on or upon solid Eplfauna
substrata, *. g. rocks, jetties, substrata, e.g . rocks, Jetties, substrata, *.9. rocks, jetties,
piers piers piers
Plankton Plankton Plankton Plankton Plankton
Phytoplankton Phytoplankton Phytoplankton Phytoplankton Phytoplanktow
Zooplankton Zooplankton Zooplankton Zooplankton Zooplankton
Mereplankton Moroplankton Maroplankton Moroplankton Meroplankton
Migratory Cwnponent Migratory Component Milratory Components Milratory Components Migratory Components
Fish Fish Ish Ish risk
Blue crabs (females) Blue crabs Blue crabs Blue crabs Blue crabs
Oyster bar
Salt marsh Brackish marsh Ollgohallne Marsh Fresh-water marsh and swetnis
Plants, e.g.: Ap,rtin, Plants, e.g. Sporting Plants Plants
alterniflora LROtens, alternifla r, 'L CXnasurold*s Invertebrates Invertebrate
Juncus Invertebrates Reptiles and amphibians eptiles and :mphlblans
Invertebrates Reptiles and amphibians Birds :Irds
Reptiles and amphibians Birds Mammals Mammals
Birds Manimals
Mammals

GEOGRAPHIC DISTRIBUTION

Hedgpeth (1957) stated that Zostera is widespread in
the cooler temperate regions of the northern and southern
hemispheres and is present in the warm latitudes. On the
east coast of North America, Zostera has been observed
from Hudson Bay to Cape Hatteras, North Carolina (Phillips,
1969). Cottam and Addy (1947) reported the distribution of
eelgrass from Maine to North Carolina. Their report was
written after Zostera started recovering from the "wasting
disease".

Ostenfeld (1918) observed eelgrass as far as 650N
during his investigations for the Danish Biological Station.
In general, eelgrass is distributed along Denmark's east
coast and extends into the Baltic Sea (Ostenfeld, 1908).
Apparently growth is not as luxuriant in the Baltic (a
brackish environment) as in the true marine environment.
Segerstrole (1957) reported Zostera in the Baltic and
Black Seas. The Zostera beds along the French Atlantic
coast have been investigated by Blois, Francax, Gaudichon
and LeBris (1961) and Ledoyer (1964). Aleem and Petit
(1952) reported eelgrass in the Canet Marshes of Southern
France. Casper (1957) and Zenkevich (1957) investigated
Zostera from the Mediterranean, Black, Caspian, and Aral
Seas. Casper (1957) reported extensive beds of Zostera
marina and Zostera nana in the northewestern part of.the
Black Sea on sandy-clay bottoms. Zostera is widely dis-
tributed in the Caspian, especially along the Eastern shore.

Millard and Harrison (1952), Scott, Harrison and Macnae
(1952), Day, Millard and Harrison (1952) and Day (1967)
have observed Zostera in South African estuaries, such as
the Knysna, Richards Bay and the Klien River Estuary.

Many excellent studies on the community structure of
Zostera have been conducted in Japan. Kikuchi (1966) In-
vestigated Z. marina in Tomioka Bay, southwest Japan.
Sando (1964T worked in Aomori Bay at the northern end of
Honshu, whereas Fuse (1962), Kita and Harada (1962),
Kitamori,Nagata and Kobayashi (1959), Nagata (1960) and
Azumo and Harada (1968) conducted research in the Seto
Inland Sea.

The saline water habitat of Z. marina provides it with
a ready "vehicle" for passive dispersion. Detached eelgrass
may be carried by currents into a new, suitable locality
(Tutin, 1938). Setch6ll (1929) observed that Zostera bed
formation can be initiated by floating rhizomes settling in
a locality suitable for growth, but not conducive to seed

Appendix 15
207

production. Therefore, to keep the bed thriving, a contin-
uous supply of live plants from an outside source is nec-
essary. McRoy (1968) observed that the reproduction stem
of Zostera, on which the seeds are found, can become detached,
along with several leaves. The entire unit is capable of
floating, thereby providing a means of transporting seeds
to a new site. This structure (stem, leaves and seeds) has
been observed in turtle grass several hundred miles from the
coast (Menzies, Zaneveld, and Pratt, 1967). Another form
of passive dispersion is by ducks eating Zostera and ingest-
ing the seeds. Arasaki (1950) recovered seeds that had
passed through duck alimentary tracts and found that a high
percentage of germination could be obtained. Likewise,
marine animals have been observed to be seed carriers
(Ostenfeld, 1914).

McRoy (1968) believed that Zostera marina originated
in the western Pacific and reached the Atlantic by one of
two routes. One theory, less accepted by McRoy, is that
eelgrass was dispersed from the Pacific through the Indian
Ocean to both sides of the Atlantic in early Tertiary times
when the Tethys Sea covered much of the Eurasian continent.
A second theory is that eelgrass migrated through the Arctic
region when the climate was milder. McRoy holds to the
latter theory because relict populations exist in the White
Sea, the Barents Sea, the Kara Sea and Hudson Bay. This
theory is also aided by the location of its fossil ancestors
and because some marine invertebrates have a similar dis-
persal pattern (McRoy, 1968).

Within the Chesapeake Bay, Zostera marina isfound in
the polyhaline zone of the lower and middle reaches of the
Bay. Its distribution in the lower Bay can be described
with some accuracy. In the summer and fall of 1973, Robert
Orth (personal communication) observed and reported the
destruction of Zostera beds by cownose rays. Personnel at
the Virginia Institute of Marine Science, concerned over
the destruction, conducted aerial flights and ground obser-
vations to determine the extent of the loss. These obser-
vations were compared with high altitude photographs taken
by NASA in October 1971. Dr. M. Wass, using the NASA photo-
graphs, results of the aerial and ground observations and
his own extensive knowledge of the Bay, provided a descrip-
tion of eelgrass distribution before and after the destruc-
tion of the beds by the rays.

Before October 1973, eelgrass beds were generally
dense around the Guinea Marshes; the north side of the York
River up to Clay Bank, areas of Ellen and Mumfort Islands,
south. side of the York around the VEPCO plant; and along
Goodwin Neck and Goodwin Islands. By October, little eel-
grass was present in the York, and it was quite sparse in
the Guinea Marshes.

Appendix 15
208

. In 1971, Zostera was present along the Severn, Ware,
North and East Rivers and within Mobjack Bay. By October
1973, it was sparse on the south side of Mobjack Bay and
around the Ware and North Rivers. However, there are some
fairly dense beds in Brown's bay.

Zostera was not sighted in the Piankatank River or the
Rappahannock River in October 1973. In 1971, it was abundant
around Gwynn's Island, along the north and south shore of the
Piankatank River up to Ginny Point. In the Rappahannock, it
was present up to Whiting Creek on the north side and to
Monaskon on the south side.

Between the Back River and Tue Marsh there are sparse
patches in the vicinity of the Drum Island flats and the
Poquoson flats. In October of 1973, Zostera beds were
densest along the eastern shore of the Bay, in particular
from the south side of Pocomoke Sound to Cherrystone Inlet.

The above-mentioned distribution cannot be taken at
face value because Zostera dies off in October and November;
therefore, some of the sparse areas may be more representative
of normal die-off conditions rather than cownose ray activity.
A survey will have to be made when Zostera is at its growth
peak (i.e., in May or June 1974) to determine the true extent
of damage caused by the rays.

In Figure 15-17, the black circles (*) represent appro-
priate locations of eelgrass beds in the lower Bay as of
fall 1973. The symbols do not represent abundance. This
information was made available by the Virginia Institute
of Marine Science. Also in Figure 17 are circles enclosing
numbers. These symbols are representative of locations
where eelgrass beds were observed between 1971 and 1973,.
This information was made available through the courtesy of
J. Kerwin and R. Munro of the Migratory Bird and Habitat
Research Laboratory of the Department of the Interior. Table
correlates the numbers with the location of the bed within
the Bay. The frequency percentage for 1971, 1972 and 1973
also is reported as well a@s the number of samples taken at
each station. The only exception is location number 24 in
the Potomac. Neither Kerwin and Munro nor the Virginia
Institute of Marine Science reported any beds in the
Potomac River; however, one bed has been observed in the
4 Potomac (May, personal communication).

Scientists cannot always keep abreast of the development
.and decline of eelgrass beds. Therefore, it Is imperative
that sites of "development" be checked for the organisms
present. Just because"an organism has not been observed at
a specific site, does not necessarily mean it has not settled
in the location.

Appendix 15
209

susqu hanna .:TS.
River

C
N

IIALTL . . . . . . .

6 %ILO %A%

OAp ximate locations of eelqrass
be%o Information from Dr.Marvin
Wass of the Virginia Institute of
Marine Science
3

23
rass
'A Approximate locations of eeig
b ds. Information from J. Kerwin
16 a*nd R. Munro of the Migratory Bird
and Habitat Research Laboratory-
Department of the Interior

%Vinforneation from Elizabeth May
10 0 10 20 personal communkation

FIGURE 15-17: DISTRIBUTION OF EELGRASS IN THE CHESAPEAKE BAY
(From M. Wass, J. Kerwin and R. Munro, personal
AppendiX 15 communication).
210 -

TABLE 15-7
EELGRASS FREQUENCY DISTRIBUTION
1971, 1972, 1973

Location Frequency Number of Sampling Stations
1971 1972 1973 1971 1972 1973

1. Eastern Bay 4.26 11.63 0.00 47 43 47
2. Choptank River 5.00 5.17 0.00 60 58 57
3. Little Choptank River 5.26 0.00 0.00 19 19 19
4. James Island-Honga River 41.18 2.94 0.00 34 34 34
S. Honga River 26.67 16.67 0.00 30 30 30
6. Bloodsworth Island 20.00 15.91 2.17 40 44 46
7. Fishing Bay 4.00 4.00 .0.00 25 25 25
8. Manokin River 33.33 40.00 13.33 is is is
9. Big and Little Annemessex Rivers 60.00 50.00 15.00 20 20 20
10. Pocomoke Sound 18.18 10.00 4.76 22 20 21
11. Patuxent River 2.00 0.00 0.00 so 47 so
12. Smith Island 29.41 45.45 0.00 17 11 12
13. Smith Island-Tangier Island 52.00 25
14. Mobjack Bay 20.00 30
is. Clump Island and Watts Island 20.00 20
16. Hampton Roads 9.09 22
17. Pocomoke Sound 16.92 65
18. Cape Charles 30.77 13
19. Mattawoman Cr. and Matchotank Cr. 24.14 29
20. Great Wicomico-Rappahannock Rivers 3.85 26
21. Rappahannock River 1.25 80
22. York River 11.63 43
23. Poquoson and Black River (VA) 68.18 22
24. Potomoc River Elisabeth May personel communication

From J. Lerwin and R. Munro of the Migratory Bird & Habitat Research Laboratory, Laurel, Md.
M
to ts
P.

DEPTH

There is not a "clear cut" range of depths where Pelgrass
is found, Tutin (1938) observed the lowest depth limit
of growth in England to be 4 meters below the'low spring
tide. Moffit (1941) reported eelgrass at a depth of 10 meters.
Along areas of the Pacific coast, eelgrass has been reported
at depths greater than 10 meters: 20 meters in the Black
Sea (Caspers, 1957) and 30 meters on the slope of La Jolla
Submarine Canyon in California (Cottam and Munro, 1954).
Ostenfeld (1908) found that eelgrass grew in the coastal
waters of Denmark at a maximum depth of 11 meters in clear
water and 5.4 meters in turbid water. In Puget Sound,
Phillips (1969) observed that eelgrass was limited to the
same maximum depth at high tide that Ostenfeld observed for
clear waters (11 meters). This water level is equivalent
to 6.6 meters below mean lower-low water. To some extent,
the depth of occurrence appears to depend on light pene-
tration and substrate.

Apparently a correlation can be made between leaf size
and depth. (In the next discussion, on substrate, it will
appear that a similar correlation can be made between leaf
size and substrate.) In a study by Phillip and Grant (1965)
it was reported that there is a change In leaf characteristics
with tidal zones. Narrow-leaved plants were found in the
intertidal zone and wide-leaved plants in the sublittoral
zone. They conducted field transplanting experiments and
found that intertidal narrow-leaved plants would grow wide
leaves when placed in the sublittoral zone and vice-versa.
McRoy (1966), also, found a correlation between leaf width
and plant density with depth. Subtidal depths illustrated
wide leaves of intermediate characteristics. McRoy stated
that gradient in the physical environment determines the
charactersitics of the eelgrass beds.

In Puget Sound, the upper limit of Zostera is the mean
lower-low water (Phillips, 1969). -Arasa-k-i-T-1950) found the
upper limit in Japan to be 10 cm below low tide. Keller
and Harris (1966) determined that the upper limit of eelgrass
occurrence depended on the length of exposure of the plant
to air. To survive and grow, it could not be exposed to air
any longer than 15% of the time. For optimum growth, Zostera
should not be exposed longer than 5% of the time. Keller
and Harris (1966) stated that in those areas where growth
is most luxuriant, eelgrass stranded during low tide is
capable of retarding the water drainage, thereby preventing
its own dessication. They believe the area of optimum
depth for eelgrass to be -1.0m below mean lower-low tide

Appendix 15
212

During their study, Keller And Harris (1966) calculated an
eelgrass resource index. They determined for South
Humboldt Bay that 90% of the total biomass of eelgrass and
about 60-67% of the eelgrass-producing acreage occurred
below mean lower-low tide. Therefore., they contended
that "in any management program designed to sustain eel-
grass stocks for waterfowl or other reasons, it would be
imperative that at least those portions of the bay below
mean lower-low tide should be preserved in an undisturbed
state". The validity of this statement needs to be deter-
mined for Chesapeake Bay.

Marsh (1970) determined in Chesapeake Bay that although
most of the epibiotic species were common to all stations,,
there were differences in their relative abundance at each
station in relation to depth. An average of 70 species
was collected from station A (0-7 m at mean low water);
76 from B (1.2 m at mean low water) and 88 from C (1.6 m
at mean low water). (Note: Marsh collected a:ll his samples
at Mumfort Island which is site 3 in Figure 21). These data
plus the average "number of organisms/g of Zostera (A=96.8
organisms/g; B=114.3 organisms/g and C=19_27T -organisms/g)
suggests that depth either directly or indirectly influences
the composition of the eelgrass community. It must be
pointed out that,statistically,station B did not differ from
station A (Marsh, personal communication). More detailed work
will have to be completed before the generality Marsh observed
can be applied over the entire Bay area where Zostera is
found.

SUBST,RATE
Tutin (1938) conceived the typical substratum for Zostera
to be firm, muddy sand, often covered with a layer of coarse
sand. Caspers (1957) found Zostera exclusively in the sandy-
clay substrate of the northwestern part of the Black Sea.
Ostenfeld (1908) found eelgrass in firm sand and soft mud
substrates. Contrarily, Phillips (1969) never observed
eelgrass in pure sand substrate. Both Marsh (1970) and Orth*
(1971) found that fine sands or very fine sands were an inte-
gral part of the total substrate composition in the areas
where they sampled in the Chesapeake Bay and York River.
Orth (1973) noted that dense beds of eelgrass can increase
the amount of finer sediments in the substrate by hindering
wave action and trapping fine grain fractions.

It was reported on page 2-63 that there appears to be a
correlation between leaf size and depth. Ostenfeld (1908)
discovered that a correlation also exists between leaf size
and the nature of the substrate. On wave-exposed coasts, he
found a narrow-leaved plant in the firm sand as deep as six

Appendix 15
213

fathoms. Conversely, in the sheltered areas, he found a
narrow-leaved form in a mixed sand and mud substrate and
a wide-leaved plant in the deeper waters where mud was the
dominant substratum.

As simply a note of interest, Phillips (1969) always
noted an odor resembling hydrogen sulfide 5-6 cm below the
surface of the substrate. Boysen-Jensen (1914) almost
always found ferrous sulfide in the muddy substrate of
eelgrass. Wood (1959 a and b) believes that Zostera sp.
is normally found in reducing conditions, which are don-
ducive to the acceleration of sulfate reduction by Microspira
(sulfur bacteria). Phillips (1969) stated that "eefp-rass
conditions the substrate and is also an integral interacting
part of it. Careless treatment (e.g. additions of pollutants,
etc.) of the marine soil may render it unfit for colonization
by seagrasses."

SALINITY

Orth (1973) observed eelgrass in the York River at a
salinity as low as 13 ppt and in the Bay as high as 26.5
ppt. Figures 15 and 16 present the relationship of salinity
and "Zostera distribution. Figure 16 is not representative
of total,Zostera distribution. Ostenfeld (1908) considered
10-30 PPt to be the optimum growth range. Arasaki (1950)
determined that eelgrass grows best in the salinity range
of 23.5-30.7 ppt. The growth rate was poor at 18.0 ppt and
non-existent at 9.1 ppt although death did not occur (Arasaki,
1950). Salinities as high as 42 ppt were tolerated in an
English bay, and in the laboratory the plants have tolerated
fresh water for two days (Tutin, 1938). Martin and Uhler
(1939) found eelgrass extending upstream,in estuaries with
salinities of 8.5 PPt. Osterhout (1917) at Mount Desert
Island, Maine, found eelgrass distributed in a locality
where therewas an alternate change of fresh and sea water
every six hours. The peculiarity of the environment led him
to propose the possibility of physiological types of Zostera.
That is, there might be a type of Zostera that cannot survive
when exposed to fresh water, whereas another type can. His
experiments revealed that the protoplasts of the leaf cells
from marine waters were affected detrimentally by freshwater,
whereas those froin the mouths of streams withstood freshwater
for several hours. Root cells from either area were killed
after exposure to freshwater for just a few minutes. Dif-
ferent reactions to different salinities by the various
structural parts of eelgrass were also Oserved by Arasaki
(1950).

Biehl and McRoy (1971), when investigating eelgrass
taken from Izembek Lagoon,.discovered that the osmotic
resistance of eelgrass over a 24-hour period ranged from

Appendix 15
214

distilled water to seawater three times that of normal sea-
water (normal seawater for the experiment = 31 PPt). When.
the salinity went above three times normal seawater (93 PPt),
the leaves were completely dead within 24 hours. Biehl and
McRoy (1971) also observed that within the salinity limit of
93 PPt for 24 hours, photosynthesis decreased in distilled
water, reached its maximum in normal seawater (31 ppt) and
then decreased again as the salinity concentration became
greater.

Once again, "hard and fast" limits cannot be established
for an environmental factor. To make decisions in regard to
the Chesapeake Bay and the-role of salinity in.Zostera pro-
duction, water managers will either have to (1) conduct
investigations themselves, (2) talk to scientists that have
worked directly upon the Bay and not published their results
or (3) make value judgements from available literature.

TEMPERATURE

Setchell (1922) proposed that the normal distribution
range for Zostera marina is in the North Temperate zone
where waters average summer temperatures from 150 to 20*C.
Any extension northward is possible because of insolation
of shallow enclosed waters, and any extension southward is
possible because of seasonal temperature lower ing during
winter and spring. According to Setchell (1922, 1929), a
temperature range of 15* to 20*C is necessary because it
is required for reproductive growth. He divided seasonal
succession into 50 increments:

1. Cold rigor period - lowest temperature
experienced-below or to 100C

2. Vegetative period - 100 to 150C

3. Reproductive period - 15* to 200C

4. Heat rigor period - 200 to the highest temp-
erature experienced

5. Recrudescent rigor period - 20* to 10*C

Setchell was emphatic in his belief that the various
stages of growth and reproduction are dependent on tempera-
tures, not on a particular length of illumination. On the
other hand, Phillips (1969) disputed Setchell's hypothesis
on the grounds that not enough emphasis has been placed on
illumination and its relationship to the flowering eelgrass
plant. In Puget Sound, Phillips observed flowers when the
temperature was well below Setchell's 150C; flowering was
initiated during April and May, months of increasing day

Appendix 15
215

length. Apparently, there was no correlation between plant
activity and water temperature. However, in Izembek Lagoon,
Alaska which is still farther north and where one would
expect the water to be even colder than Puget Sound, McRoy
(1966) observed that tidal pool plants flowered after the
pool warmed about 150C. He credited the warming to isolation
of shallow water areas instead of illumination. On this basis,
McRoy accepted Setchell's temperature regimes. In Newburyport 4
Harbor, Ispwich River, Barnstable Harbor and to some extent
Cape Cod Bay, flowering and fruiting were observed occurring
at temperatures of 24-25*C in July and August (Addy and
Aylward, 1944). This observation again does not fully agree
with Setchell's hypothesis; therefore, some doubt exists as
to the usefulness of Setchell's temperature regimes in all
localities. Investigations will have to be conducted in the
Chesapeake Bay to determine the validity of Setchell's regimes.

Zostera marina is an eurythermal plant. Biehl and
McRoy (1971) observed eelgrass experimentally survived temp-
eratures from-a low of -6*C (12 hours) to 340C (12 hours).
However, extended periods of exposure at either temperature
extreme can result in death. A point of interest arising
from Biehl and McRoy's investigation isthat tidepool Zostera
and subtidal Zostera exhibit different survival rates. Another
interesting aspect is that other environmental factors also
can affect the rate of survival, because of temperature
fluctuations. For example, Biehl and McRoy (1971) observed
that an increase in salinity allows a slightly higher resis-
tance of tidepool eelgrass to increased temperatures. Among
other temperature observations, McRoy (1969) found live eel-
grass under ice 100 cm thick with an additional 50 cm of snow
on top. In the Chesapeake Bay, Marsh (1970) and Orth (1971)
observed live eelgrass in the winter when the water temper-
ature was at O.OOC and a thin layer of ice formed on the sur-
face, and at 310C during late summer at low slack water. An
investigation similar to that of Biehl and McRoy (1971) needs
to be done for the Chesapeake*Bay to determine both the
maximum and minimum temperatures that can be withstood by
Zostera and the duration of survival.

OXYGEN

In Holland, eelgrass beds were observed to become anoxic
for several hours at night (Broekhuysen, 1.935). The anoxic
condition did not seem to affect the plants in a detrimental
manner. McRoy (1969) reported that eelgrass in Safety Lagoon,
Alaska tolerates anoxic conditions for several weeks or
months. As already mentioned, eelgrass has been observed
under 150 cm of snow and ice. McRoy (1966) determined that
Zostera is capable of active anaerobic respiration (ferm- K
entation). During anoxic conditions, this metabolic pathway
may be important for plant survival. McRoy (1969) believes
that some slow photosynthesis may occur when the plant is

Appendix 15
216

under ice and snow, but it will be very slow. The photo-
synthesic rate is dependent upon varying temperature and
light. Re lief from anaerobic conditions may occur from the
oxygen produced and stored in the leaves' lacunal system
from which oxygen can be recycled in respiration during
anoxic conditions.

When McRoy (1969) investigated anoxic conditions under
ice, he also took a few bottom samples from which he recovered
a gastropod, a bivalve, a polychaete and a filamentous alga.
How these organisms lived in anoxic waters is an intriguing
question.

IJH

Shelford and Fowler (1925) observed a diurnal pH range
of 8.8 to 7.7 for eelgrass in the San Juan channel and
adjacent areas of Washington. In general, the pH of the
water bathing eelgrass is more basic during the day because
of photosynthesis (Cameron and Mounce ' 1922). Cameron and
Mounce (1922) almost always found that the water covering an
eelgrass bed was higher in pH than the water outside the
bed. Allee (1923 a) concluded that pH has a greater effect
than dissolved oxygen on the occurrence and behavior of
organisms living in an eelgrass bed. His investigations
indicated a vertical pH gradient in the bed in the mid-
afternoon.' From bottom to top of the bed, the DH ranged from
7.3 (substrate level) to 8.5 (24 inches off the bottom) to
9.0 (30 inches off the bottom). A similar gradient was
observed at low tide, but only in the absence ofa moving
tide. McRoy (1969) observed a pH of 7.09 intheeelgrass bed
buried under 150 cm of ice and snow. This pH is low for the
marine environment; it reflects the anoxic conditions present
in the bed when McRoy made his observations. Apparently,
the effects of pH as an environmental factor have been con-
sidered less in Zostera research than salinity and temperature
factors.

WAVE, SURGE , AND CURRENT

One of the prerequisites that Ostenfeld (1908) reported
as necessary for the growth of Zostera was shelter. Where
the waves beat heavily, eelgrass is not found because the
water motion prohibits the establishment of a substrate
stable enough for the plant to become established. Ostenfeld
observed plants in regions of strong wave action, but the
leaves were narrow and short, the root--stock was strong and
the flowering shoots were not observed as often as in sheltered
bays. Phillips (1969) agreed with Ostenfeld.that persistent
shock will uproot and destroy the plants, but he also
observed luxuriant growths of eelgrass in areas where there
is.a moderate current (up to 3.5 knots).

Appendix 15
217

NUTRIENTS

The Zostera community plays an important role in the
cycling of nutrients. When nutrients enter the community,,
,they become "caught. up" in what Reid (1961) describes as
.a cycle of "biological assimilation, decomposition and
inorganic processes". Figuke 15-18 illustrates the basic
principles of nutrient cycling in the''Zostera community. 4
Nutrient X enters the community from a reservoir pool".
'This "reservoir pool" is defined by Odum (1971) as a large,
slow-moving, generally nonbiological component of nutrient
cycling (biogeochemical cycles). Examples of nutrient
sources within a reservoir pool in Figure 15-18 are
runoff, weathering, wastes and evaporation. In a broad
sense, it is physico-chemical reactions that move nutrients
from a point a to a point b. Once a nutrient is assimilated,
it becomes part of an "exchange or cycling pool", another
descriptive component of nutrient cycling designated.by
Odum (1971). It is a smaller, more intense cycle, represented
in Figure 15-18 by the solid black circle. Within this cycle,,
a nutrient is actively exchanged between organisms and the
environment. The efficiency of the system is proportional
to the loss of the nutrient into the "reservoir pool".

At the International Seagrass Workshop in Leiden, the
Netherlands, Fenchel (1973) chaired a group of scientists
who concerned themselves primarily with nutrient-cycling.
They believe that the sediments associated with eelgrass are
important sites of nutrient regeneration and that the
anoxic layer (reducing zone) of the sediments might act as
a nitrogen sink. Depicted in Figure 15-19 is a model conception
based on the one Fenchel's group proposed. It depicts how
the sediments interrelate to seagrass and the water column.
The sediments receive nitrogen as either organic nitrogen
in detritus or as dissolved organic nitrogen from the water
column. This organic nitrogen (amino acids, polypeptides
and/or proteins) is returned to the ecosystem via decomposi-
tion and as nitrogenous animal waste. Decomposition results
in oxidation of nitrogen to ammonia in both the oxic layer
(layer where oxygen is available) and anoxic layer (layer
where oxygen is not available. Ammonia can diffuse into the
water column, be further oxidized into nitrate or nitrite,
adsorbed onto sediment particles, thereby being retained in
the interstitial waters, or bound to metals present in the
sediments. Nitrate and nitrite can be further denitrified
to molecular nitrogen. Part of the N can, in turn, by
nitrogen fixation, become ammonia. IR fact, several aquatic
macrophytes and algae are capable of nitrogen fixation.
McRoy (1973) tested a theory that epiphytes living on the
leaves and b4cteria associated with the roots, might supply

Appendix 15
218

BIOSPHERE ATMOSPHIKRI

TINANSTRIAt. RUNOFF
'WX1 I WEATHIRING
WASTES.
MunicPal
Industrial

ustritus
Assimilat n
EVA ATION plankton
fish
nvert bratis Inorganic
eplf no Proc4sses
Infau a
aquatic 4; ts
(eelgra 'Ilk

YADecorm" Qs*r$
fungi - ->
bacteria
- - - - - - - - - -

(D
t'10 FIGURE 15-18: THE BIOGEOCHEMICAL CYCLE OF NUTRIENT X.
F- 0-
The large circle represents the general cycle of the
nutrient in the biosphere; whereas the smaller circle
represents the intensive recycling of the nutrient in
an ecosystem. In this case, the eelgrass community
is the represented ecosystem.

C111

H2 M02 H*3 ""4 Dissolved Sedimentation
Organic N of organic N
In petritus

#Hoxlc
5aDIMINT
Parliculato
Organic N
7
?A
N No N03 N 41 icrobes
2 4 2 t 1 0 . I toss
. ..............................4Dissolved
organic N

FIGURE 15-19: CIRCULATION OF NITROGEN IN SEAGRASS ECOSYSTEM
(From Seagr ass Ecosystems, 1973)

seagrasses with a nitrogen supply by nitrogen fixation.
His results did not reveal any measurable nitrogen fixation
associated with Z. marina. Zostera can utilize nitrate,
nitrite, ammonia and7or dissolved organic nitrogen for
plant growth,

A water manager may say "Yes, this is very interesting,
but what does it mean to me?" Boysen-Jensen (1914) was able
to show that 'Zostera is a primary contributor of nitrogen to
the sea bottom in the sheltered waters of fjords. His
analysis revealed that the nitrogen content of Zostera
was about 3%. A similar investigation should be conducted in
the Chesapeake Bay to determine if nitrogen is made avail-
able to the areas outside the bed as was observed in Boysen-
Jensen's (1914) study.

When conducting a study of sulphate reduction in Zostera
mud flats, Woods (1953) found that autoclaved Zostera, placed
in autoclaved sand and seawater, yields ferrous sulphide.
Further investigations showed that living Zostera could
cause the reduction to occur. Zostera is partially comprised
of a nitrogenous base and a sulphur compound, responsible
for Zosteral's reduction capability. Wood (1953) believed that
these two substances were of "great importance in Zostera
muds in two ways.: they may produce ferrous sulphide directly.,
and may also bring about reducing conditions that greatly
accelerate sulphate reduction by Microspirall (a bacteria).
Wood's investigation was a "break through" into understanding
the process of sulphur cycling in eelgrass beds, although
it does not explain the complete cycle.

.Zostera roots are normally in the reducing environment
of th anoxic sediment layer. In fact, its root hairs are
often in actual contact with hydrotolite (FeSH(OH)) particles
(Wood, 1959). It is known that certain bacteria (i.e. sul-
phate reducing bacteria, thiobacteria, purple bacteria and
green bacteria) are components of the. sulphur cycle. Such
algae forms are also important. The specific pathways for
the cycling of sulphur are not well known and should be
investigated.

The phosphorus cycle is probably the best-known nutrient
cycle in the aquatic environment because of the investigations
of McRoy and Barsdate (1970), McRoy, Barsdate and Nebert
(1972), and Pomeroy (1960), Pomeroy, Johannes., Odum, and
Roffman (1969), and Pomeroy, Smith and Grant (1965). Phos-
phates generally accumulate where there is a great deal of
metabolic activity (e.g. an area of cell division). Great-
est biomass of benthic plants (including eelgrass) in Great
Pond, Massachusetts was correlated with areas of highest
phosphate concentration (Conover,, 1958). Large standing
crops of eelgrass were correlated by Rockford (1951) to

Appendix 15
221

high concentrations of phosphates in interstitial waters.

McRoy and Barsdate (1970) determined sites of phospho-
rus uptake and subsequent transport by the use of radioactive
phosphorus (P). Their studies indicated that phosphate
absorption occurred in both roots and leaves, the leaves
having the greatest absorption rates. There is a tendency
for phosphate to accumulate in the roots or the leaf base
since these are the areas of the most rapid cell division.
McRoy and Barsdate (1970) were able to show that although
sediments pool phosphorus, the roots can pick it from the
sediment and transport it to the leaves which release it
into the water. Therefore, a positive feedback mechanism
keeps the phosphorus cycling. It must be pointed out, how-
ever, that the direction of transport depends upon the
relative concentration of phosphorus in the water column
and in the sediments (McRoy, Barsdate and Nebert, 1972).

McRoy, et al. (1972) demonstrated that there was a
net movement of phosphorus out of Glazenap Pass from Izembek
Lagoon to the Bering Sea.* This movement makes phosphorus
available for phytoplankton production in the open ocean.
Although there is a flux of phosphorus out of the eelgrass,
the sedimentation rate is so rapid in the bed that'there
is also local internal recycling.

Pomeroy, Smith and Grant (1965) demonstrated that
phosphate was exchanged between the water and sediments by
two processes. The first process, absorption, consists of
two steps. The more rapid of the steps.is initial absorption,,
whereas the slower is the reaction of phosphate with the
clay lattice.work. The second process is a biological process:
microorganisms control the exchange between the water column
and sediments. Pomeroy., et al. (1965) demonstrated the bio-
logical process by poisoning sediment samples. In the poisoned
samples, absorption was the only process observed, because
It is a physico-chemical process not dependent on micro-
organisms. In the unpoisoned samples, the microorganisms
were involved in the exchange of phosphate between the water
column and sediments. Pomeroy,, et al. (1965) ascertained that
the biologically controlled exchange was trivial because
the organisms involved live only in the oxidized zone of
the sediment below the surface where they exchange phosphate-
with the interstitial water, which in turn diffuses slowly
into the overlying water. The two mechanisms of exchange are
sufficient to provide benthic plants and phytoplankton with
enough phosphate for utilization even during periods of
great production (e.g.,blooms) and increased flushing (etgop
spring tide or runoff). Figure 15-20 illustrates a conceptual
idea of phosphate cycling by Fenchel, et al. (1973).

Appendix 15
222

Orgonle P
Dissolved

Phosphate
Dissolved

V
A@K kX
X
<
V.
<
x
xX/
I'K
A..
XX

noxic

10. Pholfhnte -1
DI S d

(D
too

FIGURE 15-20: CIRCULATION OF PHOSPHORUS IN SEAGRASS ECOSYSTEM
(From Seagrass Ecosystem, 1973)

MeRoy (1970) discussed the elemental composition of
eelgrass. Table 15-8 lists those elements he identi-
fied through his own experimentation or through liter-
ature research.

TABLE 15-8
ELEMENTAL COMPOSITION OF EELGRASS (McROY, 1969)

Major Elements Min or Elements Trace Elements

Oxygen Sodium Bromine
Hydrogen Chlorine Rubidium
Carbon Magnesium Fluorine
Phosphorus Potassium Nickel
Nitrogen Sulphur Barium
Calcium Molybdenum
Boron Cadmium
Silicon Copper
Iodine Cobalt
Zinc Beryllium
Iron
Aluminum
Manganese

AnDendix 15
224

SEASONAL ACTIVITY OFZOSTERA MARINA

Because of the lack of information about the seasonal
development of Zostera marina var. typica, which is the
variation found along the Atlantic coast, Setchell's (1929)
observations on development of var. latifolia, found along
the Pacific coast, will be extensively used in this report.

In Paradise Cove., California, Setchell (1920) observed
seed germination in February. Phillips (1969) observed
seed gemination in Puget Sound in June and July, whereas
Arasaki (1950) noted it between April and May in Japan.
Taylor (1957) observed germination off Prince Edward Island,
Canada in May and early June. In Japan, Arasaki (1950)
determined that the best germination rate occurred in low
salinity waters at a temperature range of 5-10*C (Taylor,
1957). However, continued low salinities checked the growth
of seedlings.

When the seed germinates, the ribbed seed covering
splits longitudinally, and the embryo protrudes. The
caulicle* elongates, carrying up the cotyledon which covers
the primary leaf bud (plumule of the embryo). (Figure 15-21A'.)
After the sheath ruptures, the plumule expands and projects
beyond it. At the same time, two adventitious roots with
root hairs grow out from the opposite side of the first
node. (Figure 15-21B) As growth continues, the first turion
(A bundle of 6 to 7 leaves) and two bundles of roots are
formed. (Figure 15-21C) After formation of the first
turion, the first season of growth generally can ge consid-
ered closed for var. typica. Figure 15-.22A@s a schematic
generalization of Setchell-'s (1929) diagram illustrating
progressive development of Zostera through four seasons.
From the scale-like, outermost leaves of the first turion
will grow a short plant of 6-7 internodes which will later
elongate and,teminate into either another turion., or
develop an erect stem on which the reproductive structure's
will be produced (Figure 15-21 D & E).

In var. latifolia, there is no rest period between
the first and second stages, but apparently there is in var.
typica. Ostenfeld (1908) found seedlings in July and August
which were known to be less than a year old because they had
not put forth a visible creeping shoot. He expected seed
germination to occur the following spring. From Ostenfeld's
(1908) information, Setchell (1929) believed var. tYDica might
have a shorter season of growth than lat-ifolia. Thererore,
var. typica would go through the first growth stage the first
season, then through a period of quiescence with the onset of
unfavorable environmental conditions, and finally into the

*Caulicle: The initial area between the radicle (rudimen-
tary root) and the cotyledons of the embryo.

Appendix 15
225

-@Cetvledeft sheath
swrrounding the planowle
D-Poteping
Ist Terfew

Seed test

Hypecolyi -Cotyl*den Sheath (ruptured)

caulldle

H"Osety'
Seed cont

soce"My W*Qts

Ist laview

Ist jolats of the
rhissume, we dweWping

Jo-

FIGURE 15-21: PROGRESSIVE DEVELOPMENT OF ZOST tRA MARINA
@modified from Setchell, 1929).

Appendix 15
.226

boll
yet
Goa wtore%

ILbuledwo

forowe

sloom

Appeudi%.
15-21 (COTL

lot Tgrion ("d)

qwleece*40
Lateral &AS

seed

Ist season

2nd season

Doveiopm*nt of the
Ist erect stem and
repred"ttlow stem ores

@lnfkmes- as
3
121 Terminal Bud
t2)
T'

Old or portion of
.rhisome disappears
leaving behind 2
rhiaome 'f -.mw 1

3rd season

end of 3rd season

FIGURE 15-22: DIAGRAM OF PROGRESSIVE DEVELOPMENT OF EELGRASS

Explanat ion: Ust season) The seed germinates and the first turion
develops. The plant enters a period of quiescence with
the onset of unfavorable conditions (2nd season). The
2nd turion develops with lateral buds. Again, the plant
enters a quiescence (3rd season). The 2nd turion gives
rise to the erect stem with its productive structures
(inflorescens). on alternate branches. The lateral buds
of the 2nd season become turions 3 with lateral buds
(end of 3rd season). The 2nd turions with erect stem
becomes disjunct. The 3rd turion and its rhizomes are
o'W@2ni

left behind. (From Setchell, 1929).

Appendix 15
228

.104

r Turlea With
fruiting stem

TWMI"I sud

4th season

(2)
.004 .13)

to,

(iL

end of 4th season

FIGURE 15-22 (cont'd)

Explanation (cont'd): The terminal bud of the 3rd season
(3) becomes the turion with the erect fruiting
I 4ZtZtth--

stem. The two lateral buds of the previous
season are now the terminal bud (end of 4th
season). Erect fruiting stem and rhizome have
become disjunct.

Appendix 15
229

second period the following growing season, Whenever the
second period of growth for either variety occurs, it is
characterized by elongation of the internodes of the old
turion, with a corresponding loss of leaves along the elon-
gated rhizome with at least two lateral turions. Figure 15-22
(second season) illustrates the formation of the second
turion with lateral turions. The new terminal turion may
have six to seven leaves; whereas, the laterals have fewer
leaves when they develop. Variety typica may produce fewer
internodes.

Both var. latifolia and var. typica undergo a period
of quiescence. However., var. latifolia and var. typica
differ in the degree to which the quiescence is enforced.
Variety typica's quiescence is generally enforced by
severe conditions of the environment, whereas the conditions
that enforce quiescence in var. latifolia are mild in com-
parison. In Zostera marina, it is during the quiescent
period that tHe -earliest produced internodes of the rhizome
die. This dying off is represented in Figure 15-22 by b.rol0n
lines in the Zostera plant at the end of the third season.

Differentiation occurs with the advent of the third
.season of growth. As the terminal turion matures., the
internodes elongate, resulting in separation of leaves
(this event may occur in the second or third season, de-
,pending on the variety). Reproductive structures (inflorescence)
are produced on alternate lateral branches of the turion (Figure
15-22 . third season). The lateral buds of the plant will
become terminal buds which in turn become the terminal turion
in the next growth season. Pollination and maturation of the
seeds continues as long as environmental conditions remain
favorable. Stems of Zostera marina var. typica reach a
length of 1-4 feet, with seven internodes and 1-5 branches.
When conditions become unfavorable, the plant again enters
a period of quiescence. Disjunction of the older portion
of the rhizome may occur during the period of growth (par-
ticularly when sampled), but the disjunction is increased
during the quiescent period. As unfavorable conditions set
in, not only do older plants of the rhizomes die and decay,,
the erect fruiting stem end its associated rhizome also
die. As the stem and rhizome die, the plant hold within the
substrate is loosened. Often, windrows of Zostera are ob-
served on,shore, the result of the reproductive stems float-
ing off after the rhizomes hold on the substrate has been
loosened. In the previous discussion of geographic distrib-
ution, it was pointed out that these floating reproductive
stems of Zostera are one means of dispersion.

Appendix 15
230

When the new season begins, the lateral turions
of the.previous growing season develop in the same manner
as the terminal turion of the previous season. The leaf
structures associated with the internode detach themselves,
and a terminal turion forms with 6-7 leaves and two smaller
lateral turions Figure 15-22 fourth season). The erect
fruiting stem forms; the reproductive structure matures
and pollination occurs. The lateral buds of the new ter-
minal turion become terminal buds. When unfavorable conditions
set in, quiescence occurs and disjunct stems and rhizomes
float away. The following season, the same cycle will occur.
Barring any adverse actions by the environment on the beds,
a geometric progression of turions should occur, and the
bed will continue to increase ad infinitum.

COMMUNITY COMPOSITION AND TROPHIC STRUCTURE

Community composition is the crux of this part of the
report on eelgrass. All previous information was presented
so that water managers would have a grasp of the ecological
factors that regularly affect Zostera marina because these
same ecological factors impinge on each and every organism
found within the Zostera bed. In the final analysis,
community structure at a particular time.or place depends on
the ability of the assembled life stages to adapt physio-
logically to the prevailing environment.

As mentioned previously, there are two definitive
investigations of the Chesapeake Bay region, [email protected], 1,970
and Orth, 1971. It is fortuitous that these works comple-
ment each other. Marsh studied eelgrass epifauna for 14
months in the lower York River Estuary in the vicinity of
big Mumfort Island, whereas Orth collected infauna in the
York River Estuary, in Back River and from both sides of
the Eastern Shore of Virginia. Figure15-23 indicates the
approximate areas investigated.

Other studies have been conducted on fauna associated
with eelgrass, such as Dodd's (1966) and McKeough's (1968)
research on the epiphytes and epizoans of Zostera blades in
Great South Bay, Long Island, New York. In Japan, Kikuchi
(1966, 1968) conducted excellent research on the ecology of
the animals living within the 'Zostera community located in
Tomioka Bay, Kumamoto Prefecture on the west coast of Kyushu.
Hatanaka and Iizuka (1962) studied the fishes that utilize
Zostera as a habitat. Work on microalgae and small animals
.of the Zostera community was conducted by Kita and-Harada
(1962) studied the fishes that utilize Zostera as a habitat.
Work on microalgae and small animals of the Zostera community
was conducted by Kita and Harada (1962). Japanese scientists
have produced several significant works related to Zostera

Appendix 15
231

Susqu hanno
River

IPA

-Owe

10A
IF
k*

W4.

Back River

York River mouth
Olviumfort Island
Clay Bank
Chesapeake Bay
Chincoteague Bay

10-- 10 20

FIGURE 15-23: SITES OF EELGRASS INVESTIGATIONS BY MARSH (1970)
Appendix 15 AND ORTH (1971)
, 232

and its associated fauna. This may in part be because of
their greater dependence on estuaries and the sea as a
protein food source. There has been some work on eelgrass
communities in Europe and North Ameican such as Blois,
Francax, Gaudichon and LeBris (1961) and Ledoye (1964 a,
and 1964 b)., Ostenfeld (1908) reported on some of the
organisms assoicated with eelgrass on the Danish Coast.
However, European and American scientists have not investi-
gated the eelgrass community as extensively as have the
Japanese.

Marsh (1970) collected 112 epibiotic invertebrate
species plus 28 macroalgal species in the Zostera beds.
His collection does not include such organisms as diatoms,
nematodes ostracods, copepods, and other small inverte-
brates which were not retained by a 0.5 mm mesh seive.
Orth (1971) collected 117 infaunal invertebrate species.
Table 15-9 represEn-ts a composite of the organisms observed
during the two investigations associated with the eelgrass
community. The value of Table 15-19 to water managers is not
intended as a "laundry list" of scientific names, but as
a revelation of the complexity of the community. However,
finding an organism in both the.infauna and epifauna, does
not necessarily indicate a normal situation.. For example,
Marsh found a very small Callinectus sapidus (blue crab)
one time in the epifauna although its normal habitat is on
the bottom. Table 15-19 is:not ccnplete. The fish associated
with eelgrass beds"are not listed because that information
is not available in the literature. Other investigations
are necessary to provide a complete list.

The five most abundant epifaunal organisms in Marsh's
study were Bittium varium, Paracerceis caudata, Crepidula
convexa. Ampi@_hoe longimana and Erichsonella attenuata.
These organisms constituted 59% he total fauna observed.
The 22 most abundant epifaunal organisms accounted for
95.5% of the fauna. In terms of dominant taxa 43.2% were
Gastropoda, 18.5% Amphipoda, 16.7% Isopoda and 15% Poly-
chaeta. Orth (1973) reported that Polychaeta constituted
36% of the total infaunal population., Amphipoda 16%.
Gastropoda 11% and Bivalvia 7%. The remaining percentage
belonged to various other taxa. Although most of the
epibiotic species of Marsh's study were common at all stations,,
differences in their relative abundance in relation to depth
were evident. An average of 70 species were collected from
station A. 26 from B, and 88 from C. This data and the
average number o 'f organisms/g of'Zost'e-ra (A - 96.8
organisms/g, B - 114.3 organisms/i -and C - 192.4 organisms/g)
suggest that depth either directly or indirectly influences
the composition of the eelgrass community. It must be
pointed out that btatistically Station B did not differ
from Station A (Marsh, personal communication).

Appendix 15
233

TABLE 15-9
ORGANISMS OF THE CHESAPEAKE EELGRASS COMMUNITY
(MARSH, 1970, and ORTH, 1971)

Marsh (1970) Orth (1971)

Porifera

1. Microciona prolifera X
2. Haliclona loosanoffi X
3. Halichondria bowerbanki X
4. Mycale sp. X
5. Prosuberites microsclerus X

Cnidaria

6. Edwardsia sp. X
7. Dynamena cornicina X
8. Halocordyle tiarella X
9. Hydractinia arge X
10. Aiptasiomorpha luciae X
11. Diadumene leucolena X

Platyhelminthes

12. Euplana gracilis X
13. Stylochus ellipticus X
14. Zygonemertes virescens X X
15. Tetrastemma elegans X
16. Amphiporus ochraceus X X
17 Amphiporus bioculatus X
18. Cerebratulus lacteus X
19. Tetrastemma sp. X
20. Tubulanus pellucidus X
21. Nemerteans (unidentified) X

Bryozoa

22. Electra crustulenta X
23. Bowerbankia gracilis X
24. Membranipora tenuis X

Polychaeta

25. Nereis succinea X X
26. Platynereis dumerilii X X
27. Sabella microphthalma X X
28. Polydora ligni X X

Appendix 15
234

TABLE 15-9 (cont'd)
ORGANISMS OF THE CHESAPEAKE EELGRASS COMMUNITY
(MARSH, 1970, and ORTH, 1971)
Marsh (1970) Orth (1971)

29. Brania clavata X X
30. Hydroides hexagona X
31. Podarke obscura X X
32. Nereiphylla fragilis X
33. Exogone dispar X X
34. Pista palmata X
35. Odontosyllis fulgurans X X
36. Lepidonotus variabilis X
37. Amphitrite ornata X
38. Asabellides oculata X
39. Clymenella torquata X
40. Eteone heteropoda X
41. E. eactea X
42. Diopatra cuprea X
43. Phyllodocidae (unidentified) X
44. Glycera americana X
45. G. dibranchiata X
46. Glycinde solitaria X
47. Gyptis vittata X
48. Heteromastus filiformis X
49. Hydroides dianthus X
50. Lepidonotus sublevis X
51. Loimia medusa X
52. Lumbrineris tenuis X
53. Melinna maculata X
54. Parahesione luteola X
55. Paraprionospio pinnata X
56. Pectinaria gouldii X
57. Phyllodoce fragllis X
58. Prionospio heterobranchia X
59. Pseudeurythoe paucibranchiata X
60. Sabellaria vulgaris X
61. Scoloplosacutus X
62. Ampharetidae (unidentified) X
63. Capitellid A (unidentified) X
64. Scoloplos armiger X
65. S. fragilis X
66. S. robustus X
67. S. sp. X
68. Spio filicornis X
69. S. setosa X
70. Spiochaetopterus oculatus X
71. Spiophanes bombyx X
72. Streblospio benedicti X
73. Tharyrx setigera X
74. Sphaerosyllis hystrix X

Oligochaeta (unidentified) X

Appendix 15
235

TABLE 15- (cont'd)
ORGANISMS OF THE CHESAPEAKE EELGRASS COMMUNITY
(MARSH, 1970, and ORTH, 1971)

Marsh (1970) Orth (1971)

Mollusca

75. Bittium varium X X
76. Crepidula convexa X
77. Mitrella lunata X X
78 Triphora nigrocincta X
79. Nassarius obsoletus X X
80. N. vibex X X
81. Odostomia impressa X X
82. 0. bisturalis X
83. Elysia catula X
84. Stiliger fuscata X
85. Polycerella conyma X
86. Doridella obscura X
87. Doris verrucosa X
88. Tenellia fuscata X
89. Gemma gemma X
90. Cratena pilata X
91. Hermaea cruciata X
92. Anadara transversa X X
93. Mya arenaria X X
94. Ensis directus X
95. Laevicardium mortoni X
96. Lyonsia hyalina X
97. Macoma balthica X
98. Mercenaria mercenaria X
99. Mulinia lateralis X
100. Acteon punctostriatus X
101. Eupleura caudata X
102. Mangelia plicosa X
103. Pyramidella candida X
104. Retusa canaliculata X
105 Triphora perversa X
106. Turbonilla interrupta X
107. T. sp. X
108. Urosaplinx cinerea X X

Arthropoda

109. Balanus improvisus X
110. Neomysis americana X X
1ll. Mysidopsis bigelowi X
112. Paracerceis caudata X X
113. Erichsonella attenuata X X
114. Idotea baltica X X
115. Edotea triloba X
116. Cyanthura burbancki X
117. Ampithoe longimana X X

Appendix 15
236

TABLE 15-9 (cont'd)
ORGANISMS OF THE CHESAPEAKE EELGRASS COMMUNITY
(MARSH, 1970, and ORTH, 1971)
Marsh (1970) Orth (1971)

118. Cymadusa compta X
119. Elasmopus laevis X X
120. Gammarus mucronatus X X
121. Caprella penantis X
122. Batea catharinensis X X
123. Corophium acherusicum X X
124. C. simile X X
125. Melita appendiculata X
126. Colomastix halichondriae X
127. Paracaprella tenuis X
128. Rudilemboides nageli X
129. Ampelisca vadorum X X
130. A. abdita X X
131. A. verrilli X
132. Jassa falcata X
133. Leptocheirus sp. X
134. Listriella barnardi X
135. Lysianassa alba X
136. Melita appendiculata X
137. M. nitida X
138. Stenothoe minuta X
139. Unciola irrorata X
140. Callinectes sapidus X X
141. Crangon septemspinosa X X
142. Lembos smithi X
143. Monoculodes edwardsi X
144. Heterophoxus sp. X
145. Cucumaria pulcherrima X
146. Thyone briareus X
147. Anoplodactylus parvus X
148. Cylindroleberis mariae X
149. Sarsiella zostericola X
150. S. texana X
151. Callipallene brevirostris X
152. Cyclaspis varians X
153. Oxyurostylis smithi X
154. Leptochelia savigny X
155. Hippolyte pleuracantha X
156. Palaemontes pugio X
157. P. vulgaris X
158. Neopanopa texana sayi X
159. Libinia dubia X
160. Molgula manhattensis X
161. Botryllus schlosseri X

Echiodermata

162. Cucumaria pulcherrima X
163. Thyone briareus X

Appendix 15
237

Orth (personal communication) revealed some interesting
points on community composition. Comparative data of a
bare sand habitat and a Zostera bed indicated an approximate
fourfold increase innumbers of organisms within the ' Zostera
bed. He also has determined that the majority of organisms
inhabiting Zostera beds are tube dwellers rather than mud
dwellers. In Zostera, tube dwellers are not subject to the
same degree of stress they would be subjected to in bare
sand. An organism living in bare sand must burrow rapidly
or be enclosed in a long tube to prevent smothering by shift-
Ing sand.

Marsh (1970) used Sanderls (1960) index of affinity on
.each collection date to indicate faunal similarity between
stations off Mumfort Island (site 3 in Figure 15-23), and he
also used Duncan's multiple range test (Steel & Torrie, 1960)
to indicate significant differences in the average faunal
affinity between station pairs. He found the affinity between
stations A and B averaged 69.9%, between B and C averaged
58.3% and between A and C averaged 46.1%. Station C was
distinct because of the appearance of eelgrass, its lower
biomass and the abundance of certain algae epiphytes. The
affinity values calculated by Marsh were relatively high in
comparison to other community studies (Sanders, 1958:
McCloskey, 1968) when affinity values were determined.
These values establish a distance relationship of continuity
between the epifauna.

In describing faunal similarity, Orth (1970). used the
dominance affinity index or percentage similarity, Kendall's
coefficient of association T and the Wisconsin variant of
percentage similarity. All three tests were used to compute
values between station pairs, whereas just the percentage
similarity index and Kendall's T were used to compute dif-
ferences between peasonal samples. In general, the mean
index for the station pairs within seasons was 39% in March
and 41% in July. The similarity of the infauna between
seasons was found to be relatively low with a mean of only
31%. The results indicate that a similarity pattern of the
infauna of 'Zostera within the Chesapeake exists, especially
between adjacent stations.

The information function of Shannon (Shannon & Weaver.,
1933) is a common diversity index which Marsh (1970) used
because it is sensitive to the number of forms present and
the equitability of their distribution, yet relatively in-
dependent of sample size.. The equitability component of
diversity also was utilized to describe the theoretical
distribution of individuals among species. The two com-
putations demonstrated that on a seasonal basis there is

Appendix-15
23@

not a marked seasonal diversity. Orth (1973) calculated
diversity, evenness and species richness. His results
appeared quite similar to Marsh?s in that there was not a
distinct seasonal pattern for diversity (although the
species components decreased from stations A to D both
seasons).

Thus far, we have been concerned only with the inverte-
brate epifauna and infauna of the Zostera bed, which com-
prises only part of the total picture. Zoitera provides
a substrate for many epiphytes. Table 15-10 is a list of macro-
algal epiphytes found on Zostera leaves by Marsh. Marsh
(1970) did observe a distinct seasonality among algal genera.
In the winter, Desmotrichum and Elachistia (brown algae)
were dominant, whereas Champia, Spyridia and Agardhiella
(red algae) were dominant in summer and fall. Depth
apparently affected some of the algae because Champia and
Fosliella were found at shallow inshore stations., whereas
in deep waters Enteromorpha intestinalis and Ceramium rubrum
were common. Also during his investigation, Marsh took
surface scrapings of the eelgrass blades which revealed-great
numbers of nematodes, rotifers, diatoms and other microorgan-
isms as well as quantities of-detritus and sediments.

Marsh concluded that there are three primary food
sources within a Zostera bed:

1. "Detritus and microorganisms found on the
plant surfaces"

2. "Suspended particulate organic matter and
plankton"

3. "Epiphytic algae"

A fourth food source is the detritus formed from dead
Zostera leaves (Kita and Harada, 1962). In our area,
live Zostera does not appear to be directly utilized for
food except by ducks and geese, such as the Brant, Canada
Goose, Scaups and Redheads. Of the three food sources
reported by Marsh, 21 of the 22 most abundant species
(equivalent to 95% of the total fauna) in the Chesapeake
Bay were dependent on at least one of them. The exception,
Odostomia impressa, is an ecotoparasite on various inverte-
brates.

Appendix 15
239

TABLE 15-10
MACROALGAE OBSERVED ON ZOSTERA LEAVES (MARSH, 1970)

Chlorophyta Rhodophyta

1. Ulva lactuca 13. Grinnellia americana

2. Bryopsis plumosa 14. Porphyra leucosticta

3- -Enteromorpha plumosa 15. Agardhiella tenera
4. E. intestinalis 16. Callithamnion byssoides

5. E. linza 17. Ceramium fastigiatum
6. Cladophora gracilis 18. C. rubrum

7. C. glaucescens 19.- C. diaphanum

8. Chaetomorpha linum 20. C. rubriforme

21. Polysiphonia nigrescens

Phaeophyta 22. P. subtillislma

9. Desmotrichum undulatum 23. P. 1-arveyi

10. Asperococcus siliculosus 24. Dasya pedicellata

lls Elachistia sp. 25. Champia parvula

12. Scytosiphon lomentari.a 26. Spyridia filamentosa

27. Fosliella lejolisii

Appendix 15
240

It has already been mentioned that numerous nematodes,
rotifers, diatoms-and other microorganisms as well as
detritus and sediment are found on Zostera leaves. This
material is grazed upon by many mollusks, isopods, amphipods
and polychaetes. Sponges, tunicates and bryozoans are some
of the common suspension feeders. Other organisms such
as caprellid amphipods, mysid shrimp and polychaetes are
known to utilize both suspended particles and detrital
material as food sources. Other studies have similar
relationships, but one of interest that will be discussed
here is Nagle's (1968) study on the distribution of epibiota.

Nagle observed that infauna can "spill" over onto
the plants, but numbers of organisms decrease with the
increasing distance up the stem, whereas suspension-feeding,
fouling organisms increase up the stem. Marsh believed
that m-acroalgae are not an important food source, but
rather supplement the diet of organisms such as the poly-
chaete.s Platynereis dumerili and Nereis succinea. Nagle
found a similar situation in both field observations and
laboratory experiments. The epiphytes serve as detrital
traps, and the grazers clean the epiphytes by utilizing
the detritus as a food source. Only in time of distress
will the epiphytes be used as food. The epiphytes benefit
because they remain strong and healthy.

Another aspect or interest Nagle demonstrated was
that the organisms relatively immune to fish predation,
such as snails and amphipods of the genus Corophium,
demonstrate a peripheral zonation. Those amphipods more
susceptible to predation live nearer the center or the
stem where there is more protection. A striking resem-
blance often is discerned between the coloration and bars
of diatoms and those of snails.

Nagle also was able to show that some organisms prefer
areas of high physical energy, whereas others prefer lower
energy areas. Usually this difference is related to the
ability of the organism to gather food and is dependent on
morphological adaptation. One last point of interest is
that interspecific organisms often have staggered reproduc-
tive periods. This staggering allows niche coexistence
since the adult form of one species and the larval form
of another species are present at the same time. The
different life stages have different food requirements,
and therefore do not compete for the same food. A
similar study to Nagle's would be beneficial for the
Chesapeake Bay..

Appendix 15
241

Several organisms are predators of the invertebrate
fauna, such as Urosalpinx cinerea and Odostomia im2ressa
(Marsh 1970). In summer, fishes such as common silver-
sides (Menidia menidia), the four-spined-stickleback
(Apeltes iTu-adracus) and the pipefish (Syngnathus fuscus)
utilize amphipods, mysids, other small crustaceans and some
polychaetes as food sources. Figure 15-24 taken from Marsh
(1970), demonstrates an apparent trophic relationship of
the common epifaunal genera.

Work has been published by the Japanese on the
relationship of fish and Zostera. An interesting study was
conducted by Kikuchi (196ET on-the fish community of Zostera
marina in Tomioka Bay. A comparison was attempted for this
report to see if parallelism could be demonstrated between
the Tomioka (1966) and Chesapeake Bays. For the most
part, it could not. However, a similar study for the
Chesapeake would be valuable.

Kikuchi (1966) described microhabitats within the
Zostera belt:

1. "the surface layer water above the vegetation"

2. "the bottom layer water in the vegetationli

3. "the surface of Zostera blades"

4. "the surface of the substratum"

5. "the inside of the substratum"

He then related the fish to these microhabitats and described
their behavior, social.relations and feeding rites. Behav-
ior included such activities as swimming slowly or resting
on Zostera, whereas social relations included their manner
of interacting with others of their species (e.g. did
they school or were they solitary?) The rite refers.to
the microhabitat fish utilize for obtaining food. He
carried his investigation one step farther, and described
the various fishes as to how long they lived in the Zostera
belt. Table 15-11 generalizes how he accomplished this task.

Appendix 15

sl xTpuaddV

m 00

C,
ON a 10
0

Vs,

10
Q

4ft

TABLE 15-11
KIKUCHI'S CLASSIFICATION OF FISHES
ASSOCIATED WITH ZOSTERA (1966)

1. Residents (fish residing in the Zoastera belt
year round).
a. Fishes which utilize the belt as their
only habitat
b. Fishes in common with rocky coast.
c. Fishes in common with muddy or sandy
bottoms.

2. Seasonal residents (fishes which spend definite
seasons or definite life stages in the Zost'era belt).
a. In spawning season
b. In juvenile and subadult stages

3. Transients (fishes which forage about a larger
area in the bay and come to the Zostera belt as
part of their foraging range). '

4. Causal species (fishes which casually appear
in the Zostera belt).

Although the method in Tablel5_11 may not be entirely
utilized in the Chesapeake Bay, a good part of it is
appropriate for the Bay. A generalized statement Kikuchi
made that would be worth investigation is that "the year
round residents are small in their adult size, large
species are transients, and juvenile seasonal inhabitants
are of a size similar to those of year-round residents."
Kikuchi (1966) continued his study with investigators
of decapod crustaceans. Decapods are important because of
their significance as fish food. Crustaceans show noctur-
nal behavior so they were collected at night, something
that has not been done in the Chesapeake Bay to my know-
ledge. -The crustaceans were classified much like the
fish in Table 15-11.

In his study of other invertebrates, Kikuchi (1966)
portrayed an organism in its microhabitat similar to the
way he did fish except he substituted the mode of life
(swimming, creeping or crawling sessile) and mode of
feeding (seston, plankton, herbivore, or predator) into
the classification. In general, he found that the infauna

Appendix 15
244

of the Zostera belt were similar to that of the surrounding
bare muddy bottom or muddy sand bottom. The epifauna exists
only on the Zostera vegetation and was not observed on
bare bottom. He considers a Kost'era community relatively
independent.

WASTING DI*SEASE

Another reason the Zostera community was chosen for
additional study in this report was because of its reported
decline in 1931 and 1932 which resulted in the death of a
dominant organism, Zostera marina, over large areas. By
the end of the fall of 1931, about 90% of the eelgrass located
along the Atlantic coast had been eliminated by some unknown
factor (Moffit, 1941). From 1931 to 1941, Zostera was re-
ported declining in several parts of the globe. Lewis and
Taylor (1933) noted its decimation from Nova Scotia to North
Carolina,, whereas Taylor (1933) noted the decline on the
French and Netherlands coast. Blegvad (1935) reported the
progressive destruction of eelgrass along the coasts of
Portugal, France, and Holland during the early part of 1932
and early 1933. In the Limfjord, he observed the first
effects on growing Zostera in deep water on soft bottoms.
In 1941, the Danish stock was 1/13th of its former total and
was limited to slightly saline water (Lund, 1941). Fischer-
Piette, Heim and Lami (1932) reported the disease in France,
where they described the symptoms and isolated a gram-
negative rod bacterium which they believed might be the
causative agent. On the English coast, Atkins (1947) reported
a 70-75% loss of Zostera in Guernsey in 1932,, and Wilson (1949)
reported a decline in Salcombe Harbor and the resultant effects
upon the shore. During a ten-year period (1941-1951), Zostera
slowly regained its population, but the decimation that struck
then could strike again. As late as 1964, a decimation of
Zostera was observed in the vicinity of Auckland, New Zealand
(ArmTg-er, 1964).

Many theories have arisen as to what caused the destruc-
tion of the eelgrass. Tutin (1938) suggested that a lack of
sunshine might be the reason, but Atkins (1938) quickly pointed
out that Tutin's theory could not be correlated with the
meteorological data available from 1897 onward. Butcher (1934),
and Duncan (1933) suggested crude oil spillage, but this
theory has little support. Cottam (1933), for one did not
believe oil pollution could be correlated with the decline.
There was a lot of speculation, but the controversy seems to
reside in two fungal-like organisms. In Canada, Ophiobolus
lamimus was reported by Mouance and Biebl (1934) to be asso-
ciated with the rhizomes and fertile shoots of Zostera. They
also demonstrated its development on the leaves of Zostera
kept in seawater in the laboratory. Petersen (1935T-believed
that in Danish waters the fungus Ophiobolus was the pathogen

A-Ppendix 15
245

and not a bacterium or the protozoan Labyrinthula which was
first reported by Renn (1934), after a superficial examina-
tion, as the causative agent. After a more detailed investi-
gation, Renn (1936) stated that although Ophiobolus lamimus
was reported as abundant along the Canadian, Danish and English
coasts, it was an infrequent species from Maine southward.
He believed that the ameoba-like organism, Labyrinthula with
Its mycetozoan affinities was the causative agent. by means
of histological examinations and inoculation experts, he
was able to make a fair assumption that Labyrinthula was the
causative agent. Young (1943) gave support to Renn's theory
because his work also led him to believe that Labyrinthula
was the etiologic agent of the eelgrass "wasting disease. TV
His investigation revealed that the optimum temperature for
Labyrinthula was 140 to 200C, but he also found it active
from 0-30C to 300C. Salinity appeared to be an inhibitor of
the organism's growth; the vegetative stage did not do well
in low salinity waters. Cottam and Munro (1954) stated that
in both Maryland and Virginia low salinities in the adjacent
tributaries of the Chesapeake Bay were conducive to the
recovery of eelgrass., whereas along the oceanic coast, It
was at the time of their publication still non-existent.

A water manager's prime concern should be the effect
of disruption on a community If it Is disturbed. In regard
to Zostera, he can get an excellent idea because as the eel-
grass was decimated, a noticeable decline occurred in several
marine Industries. Milne and Milne (1951) reported the
reduction of cod, flounder, shellfish, scallops and crabs.
Dexter (1944) stated soft-shelled clams and razor clams,
lobsters, and mud crabs declined severely. Mya arenaria, the
soft-shell clam, became so scarce that the industry became
non-existent. Moffit and Cottam (1941) reported the decline of
perch and herring. Stauffer (1937) observed, after Zostera dis-
appeared, a reduction of 1/3 of the total number of species
of the Woods Hole area reported by Allee (1932). Table 15-12
illustrates the relative abundance of characteristic species
before and after the disappearance of eelgrass. Moffit and
Cottam. (1941) reported a decline of 80% of the sea brant
along the Atlantic coast. They also pointed out a decline
in numbers of Canada geese, black duck, scaups, and red-
heads.

However, in one location, the decline of eelgrass helped
an industry. In the Niantic River in Connecticut, the
scallop population increased (fdarshall, 1947). The increase
was probably because the currents carried nutrients to the
area that had been stifled previously by the Zostera. Not
all the organisms associated with Zostera disappeared.
Dexter (1944) observed that some members survived by living
on algae such as Laminaria. It should be apparent that

Appendix 15
246

TABLE 15-12
SPECIES OCCURRENCE BEFORE AND AFTER
DISAPPEARANCE OF EELGRASS

Occurrence
I. ANIMALS FORMERLY GROWING
ON THE PLANTS
Before After

Coelenterata: *4
Sagartia luciae
Bryozoa:
Bugula turrita
Arthropoda:
Idothea baltica
Mollusca:
Bittium alternatum
Lacuna vincta
Littorina sp.
Mitrella lunata

Total number of characteristic
epiphytic species 7 1

II. ANIMAIS FORMERLY SWIMMING
AMONG THE PLANTS

Annelida:
Podarke obscura
Arthropoda:
Crago septemspinosus

3Allee (1923) listed 138 species found in the eelgrass
areaj,from 1915 to 1921.
Occasional: Before--found in less than 33 per cent
of Allee's collection.
After --- forming less than 2 per cent of
the 1936 population.
"Common: Before--in 33 per cent to 50 per cent of
Allee's collections.
After --- forming 2 per cent to 5 per cent
of total population.
-***Abundant: Before--in over 50 per cent of Allee's
collections.
After --- forming S per cent or more of
the total population.

Note: The relative abundance of characteristic species
in N.W. Gutter lagoon befo e and after the dis-
appearance of the eeigrassi. (From Stauffer, 1937)

Appendix 15
247

TABLE 15-12 (cont'd)
SPECIES OCCURRENCE BEFORE AND AFTER
DISAPPEARANCE OF EELGRASS

Occurrence
II. ANIMALS FORMERLY SWIMMING
AMONG THE PLANTS
(cont'd) Before After

Gammarus sp. ** **
Palaemonetes vulgaris ** **
Virbius zostericola **
Mollusca:
Pecten irradians **

Total number of characteristic
swimming species 6 3

III. ANIMALS LIVING ON THE SURFACE 0F THE MUD

Coelenterata:
Hydractinia echinata ** **
Arthropoda:
Carcinides maenas ** **
Libinia dubia ** **
Libinia emarginata ** **
Pagurus longicarpus *** ***
Pagurus pollicaris * *
Neopanope texana sayi ** **
Limulus polyphemus ** *
Mollusca:
Crepidula convexa ** **
Crepidula fornicata * *
Crepidula plana ** *
Nassa obsoleta *** **
Nassa trivittata ** **
Modiclus demissus ***
Mytilus edulis **
Ostraea virginica * *

Total number of characteristic
mud surface species 16 12

IV. BURROWING FORMS

Nemertea:
Cerebratulus lactens * *
Micrura leidyi ***

Appendix 15
248

TABLE 15-12 (cont'd)
SPECIES OCCURRENCE BEFORE AND AFTER
DISAPPEARANCE OF EELGRASS

Occurrence
IV. BURROWING FORMS
(cont'd) Before After

Echinodermata:
Leptosynaeta inhaerens
Thyone bri-areus
Anneliaa:
Amphitrite ornata
Arabella opalina
Cistenides gouldi
Clymenella torquata
Diopatra carea
Glycera sp.
Lumbrinereis tenuis
Raldane urceolata
Nerei-sv-irens.
Scoloplos I-r-agilis
S setosa
P olosoma gouldi
Arthropoda:
Pinnixia chaetopterana
Mollusca:
C tellinoides
E rectus
R -ac -tr a -1-a-t e-r-aT i s
M arenaria
olemya velum
Tellina tenera
Venus mercTn-aria
Chordata:
Dolichoglossu5 kowalevskyi

Total number of characteristic
burrowing species 25 20
Grand total of characteristic
species 55 36

Appendix 15
249

the Zostera loss resulted in a loss of feeding grounds,
support and shelter for fish, invertebrates., and epiphytes.
Stauffer (1937) pointed out that indirect effects could
result in changes in patterns of the water circulation,
amounts of dissolved'oxygen and pH.

The loss of eelgrass resulted in the shifting of mud
and sand by the tides which killed a great many other plants
and animals. As a final result, the whole ecological
community was altered (Clarkes 1954). Probably no one
could accurately estimate the economic effect of the
loss of Zostera.

After 1941, Zostera started making substantial growth
gains. Dexter (1-9-5-0T -in his study in Goose Cove at Cape
Ann, Massachusetts showed that the whole complex of animals
returned when eelgrass returned. Although eelgrass has
returned, the "wasting disease" could possible decimate it
again. As already pointed out by Orth (personal communi-
cation) the cownose ray is causing extensive damage in the
lower bay. What, effect will this destructi-on have on fish
that use the eelgrass beds as nursery grounds? If it
continues, we can expect the same results observed in the
1930's.

OYSTER COMMUNITY

Oyster bars represent another type of community. Here,
an animal rather than a plant is the dominant controller of
energy flow. This type of community, found mainly in the
mesohaline zone, is formed when young oysters attach them-
selves to a suitable substrate. Succeeding generations
of oysters attach to the original settlers, increasing the
length, width and height of the area suitable as a substrate.
An oyster bar, as it increases in size, has a great effect
on altering current patterns and velocity,and on structure.
The bar also provides a substrate for species which in turn
form a distinct faunal composition. The pictorial portrayal
presented in Figure 15-@25 shows several of the organisms associated
with an oyster bar community. Many forms of algae, hydroids,
bryozoans, barnacles., mussels and tube-building worms can
be found in such a community Chestnut (1974).

Because of the commercial value of oysters, information
on them is abundant. This portion of the oyster community
description will be limited to the oyster Crassostrea
virginica, found in the Chesapeake Bay and associated
tributaries. A detailed description will not be presented
here because much of the literature has already been synthe-
sized by Korringa (1952) and Galtsoff (1964). both infinitely
better prepared than I to prepare such a report.

Appendix 155
250

IX I

%
AAN,

Ve
0.1 .1.

A-Z

FIGURE 15-25: SKETCH OF AN OYSTER CLUMP FROM SOUTH BAY, NEAR PORT ISABEL, TEXAS.

Animals represented include the anemone, Aiptasia pallida; the brittlestar,
Ophiothrix angulata;.the cucumber, Thyonacta sabanallensis; a chiton,
Ischnochiton papillosus; Brachidontes exustus, Crepidula fornicata, and
Anachis avara, various wormis, barnacles, anTa small xanthid crab (Odum
and Copeland, in press).

Appendix 15
251

The material presented is an extract of the information
most directly applicable to the Chesapeake Bay. Both
Korringa's (1952) and Galtsoff's (1964) reports have been
relied on heavily; other literature sources have been
used as supplemental material.

In general,, the various species of oysters occupy many
square miles of littoral and intertidal zones in coastal
waters between 64*N and 44*S (Galtsoff, 1964). Galtsoffts
(1964) observations over the years led him to believe that
certain major environmental factors are common to all oyster
bottoms. He considered these factors as representing two
major subdivisions: the positive factors of the environ-
ment, including type of bottom, water movements, salinity,
temperature and food, and the negative factors of environment,
e.g., sedimentation and disease.

These positive and negative environmental factors will
be discussed in succeeding paragraphs. All information for
this discussion was derived from Galtsoff (1964)-,unless
another literature source is,cited.

POSITIVE FACTORS OF ENVIRONMENT

Oysters cannot survive on bottoms of shifting sand and
soft mud. As a rule of thumb,, a water manager can assume
that a bottom that will not support the weight of one shell
will be entirely unsuitable for oyster bar development.
Normally, oysters will be found on hard rocky bottoms on
semi-hard mud. They may also be found on submerged logs.,
or on man-made objects, (e.g. jetties, piers, etc.). If
the suitable surfaces, however, are exposed to several
hours of temperature below freezing, oysters will not occupy
the habitat.

There are several ways to convert bottoms in order
to obtain the desired firmness for oyster bar growth. One
of the most practical ways is to deposit empty oyster and
clam shells along the bottom where other environmental
conditions are favorable for oyster growth. This substrate
will provide the desired firmness for attachment of the
spat. Another method to provide a suitable substrate is
to dump gravel and/or slag from blast furnaces on the
bottom,-but this action is more expensive than the above-
mentioned method. Oysters themselves have been known to con-
vert a soft muddy area into a suitable area for settlement
and development. Several larvae attach themselves to a
hard object on the surface of the mud. A cluster is formed,
and as the oysters die, shells fall from the cluster, pro"
viding additional hard substrate, Obviously this method,
although more natural, is slower than the depositing of
shells, gravel or slag.

Appendix 15
252

Another positive environmental factor is water move-
ment. Growth, fattening and reproduction all depend upon
the oyster having a free circulation between its body
tissues and the surrounding water. Galtsoff cited the ideal
condition as a steady, nonturbulent flow of water over an
oyster bed, strong enough to carry away the liquid and
gaseous metabolites and feces and capable of supplying
oxygen and food.

The increased distribution of oyster bars depends on
water movement since the larvae are carried by currents.
When it is time for the larvae to set, the currents are the
determining factor of whether or not the larvae contact a
hard surface. Estuaries have been noted for a long time as
suitable for the expansion of oyster communities and for the
rehabilitation of populations which have been reduced by
harvesting. The oscillating movement of tidal waters carries
the larvae back and forth so that eventually they will re-
settle somewhere beyond their place of origin, whether it is
the same bar or further up or down the estuary.

As mentioned previously, the type of oscillation
that prevails in a specific estuary depends on a variety of
physical factors (i.e. size, depth, bottom configurations,
river flow and the vertical salinity gradient from the
head to the mouth of the estuary). The distribution of
oysters and the transport of sediments, pollutants and
plankton, including larvae of other sedentary invertebrates,
depend upon circulation patterns and mixing of the waters.
These factors determine where the larvae will set and the
sedimentation rate. If the sedimentation rate is great,
oysters can be smothered, but if the mixing water maintains
the particles in suspension, they may not affect the oyster
community at all. The circulation pattern will determine if
pollutants contact the oysters, and the amount of mixing
will determine the concentration of the pollutant. to which
the oyster is exposed. If mixing is fairly good, the pol-
lutant will be diluted to such an extent that its effect
on the community is minimal.

Since oysters are sedentary, their food source must be
carried to them. Certain phytoplankters are one food
source. The plankton may be brought in contact with the
oyster bar or may be carried over it, depending on the
circulation pattern and mixing. Water movement also in-
fluences the amount of competition to which the oysters
are exposed. If the larvae of other sedentary invertebrates
settle in close proximity to the oyster bed, they may com-
pete with the oyster for living space and food.

Oyster larvae, as well as other bivalves and barnaclesq
have a tendency to swarm; therefore, their distribution

Appendix 15
253

may not be uniform, even in a homogeneous environment.
Observations by Carriker (1951), Manning and Whaley (1955).
and Nelson (1952) led to the conclusion that there is a
tendency of the late umbo larvae of Crassostrea virginica
to remain in the lower and more saline waters of an estuary.
They are probably stimulated to swim by salinity changes at
flood tide (Galtsoff, 1964).

Turbulent patterns of water movement with high vel-
ocities are not conducive to oyster development. A high
velocity current will carry the young larvae away, making
rehabilitation of the bed impossible. In addition, the
small pebbles and sand carried by ahigh velocity turbulent
current can cause abrasion of the shells and valves of the
oyster.

Calculations from Galtsoff's investigations show that
an average Crassostrea virginica can filter 15 liters of
water per hour under optimal conditions. There are 250
oysters to a bushel and 1,000 bushels per acre. At this
rate, 3.75 million liters of water would be needed per acre
of water per hour. Since oysters cannot take in water more
than two inches from the shell, it should be apparent to
a water manager that a large quantity of water will have to
pass over an oyster to insure adequate waste removal, re-
plenishment of oxygen and food supply.

Crassostrea virginica, because it occupies estuaries,
tidal rivers and streams,'faces diurnal, seasonal and
annual fluctuations. The average salinity range for oysters
is between 5 and 30 PPt. Populations living above or below
this range exist under marginal conditions. Beaven (1946)
was able to demonstrate that each period of excessive
stream flow from the Susquehanna River resulted in a period
of low salinity in the upper Bay. In contrast, precipi-
tation did not cause a corresponding decline in salinity.
It is Beaven's contention that periods of heavy mortalities
in the upper Bay are correlated with periods of frequent
and prolonged exposure to low salinities that result from
runoff of the Susquehanna River. These low salinities are
also responsible for the erratic production and slow
growth characteristic of the oyster.areas above Kent Island.
Because the bars with the greatest death rate were above
Baltimore, Beaven (1946) ruled out the mortalities being
caused by industrial pollutants. Freshets in the James
River, Virginia also have been observed to cause oyster
mortalities.
Oysters can be "conditioned" to low salinities. 4
Andrews, Haven and Quayle (1959) found that oysters
living in low salinities exhibit a low physiological state,

Appendix 15
254

characterized by absence of heart beat, absence of
ciliary motion and loss of mantle sensitivity. This "con-
ditioning" permits an oyster to survive both low salinities
and low temperatures for a prolonged period of time. The
degree of survival needs to be tested. It has long been
known that oysters can survive adverse conditions if
not exposed to them indefinitely. Loosanoff and Smith
(1949) and Loosanoff (1952) demonstrated that oysters con-
ditioned to live in low salinities can tolerate still
lower salinities for a period of time, but those oysters
conditioned to high salinity waters cannot withstand the
very low salinities the oyster of lower salinities can
tolerate. Loosanoff showed that C. virginica can withstand
short durations of a change from T-ow to high salinity with-
out experiencing physiological injuries; however, tissue
starvation can occur with prolonged exposure to low salinities
(Korringa, 1952). Korringa (1952) believes that C. virginica
is like many other estuarine species in that it has a wide
tqlerance of environmental changes, but thrives especially
well under estuarine conditions because its normal compet-
itors in the more saline waters cannot endure the low sal-
inities of estuaries. Butler (1949 a) showed that repro-
ductive capability of oysters'is inhibited by the low
salinities of the marginal areas of the upper Chesapeake
Bay because the gonads fail to develop.

There are also areas of high salinity which are less
conducive to oyster production because of the presence of
predators such as drills, starfishes and boring sponges.
Galtsoff reported on observations made by Parker (1955).
Parker noted that central Texas bays experienced increased
salinity because of the six-year drought (1948-1953).
With increasing salinity, there was a gradual replacement
of most of the C. virginica by Ostrea equestris. Other
reasons for thi*@_c nge are not known. The C. virginica
that survived developed different shell char5Tet-eristics:
the valves became crenulated, and the shell became thin,
sharp and highly pigmented. Such morphological changes
have not been reported for the Chesapeake Bay but a
permanent salinity change could cause them.

Temperature is always an important factor for any
organism; oysters are no exception. Galtsoff reported
that C. virginica has been known to exist from 1*C in winter
in no7thern stat(@s to 36*C in Texas, Florida and Louisiana.
Korringa (1952) stated that C. virginica has survived
freezing of body tissues under'certain conditions (Needler,
1941 a; Loosanoff, 1946). When thawed carefully with a min-
imum of handling, they survive. Normally exposure of two
to three hours is maximum for oysters in the tidal zone to
withstand before death results.

Appendix 15
255

The physiological aspects of oyster well-being, such
as rate of water transport, respiration, feeding, gonad
formation and spawning are all.controlled to a large extent
by temperature. Galtsoff reported that at 6* to 70C, C.
virj@inica ceases to feed. At 250 to 26*C, ciliary activity,
which is responsible for water transport, is at its maximum
rate. Above 320C, the movement of cilia rapidly declines.
At 42*C nearly all of the body functions cease or are reduced
.to a minimum. The temperature has to be 20*C or above for
mass spawning and setting to occur.

The actions of salinity and temperature often integrate
to such a degree that it is difficult to separate the single
effect of either one. For example, oysters were moved
from low salinities (10 to 12 ppt) of the upper Bay and
were transplanted to Sinepuxent Bay, where the salinity
ranged from 32 to 33PPt. All the oysters perished in three
to four weeks. It has already been pointed out that oysters
can survive a change from low to high salinity without
physiological injury. So what caused the mortalities?
Galtsoff stated that the transplant was made when the tem-
perature was high and that the heat, coupled with high
salinity, caused the mortalities. Transplanting during
cooler weather caused only minimal casualities.

During this discussion on positive environmental
factors, something should be said concerning oxygen and
pH. Anyone who has ever bought oysters at the docks knows
that oysters can withstand prolonged periods out of the
water. They simply close their shell. Korringa (1952)
was not sure whether the limits to length of exposure were
a result of loss of moisture or respiratory difficulties.
It also is not known whether or not oysters are influenced
by oxygen in the air. When processing oysters for marketing,
it should be remembered that the metabolic rate is greatly
increased to satisfy the oxygen debt incurred by removal
from water and maintenance in air. As far as pH is con-
cerned, Korringa (1952) reported that Loosanoff and Tommers
(1947) observed that a lowering of pH below 7.0 reduces
the rate of water pumping in C. virginica. An acidic
situation does not occur ofteH-, but with increase in pol-
lution, it could happen. A large scale acid spill or dump-
ing of acidic wastes into an estuary would cause this con-
dition. It must be pointed out that oyster populations can
themselves create an acidic condition by overcrowding and
fouling of shells. Water managers should be aware that the
Chesapeake Bay is one of the most productive estuaries in
the world. Any contaminant that irritates the oyster's
neuromuscular system causes increased shell movement, which
in turn increases oxygen demand and results in the burning-
up of the reserve supply in the body tissues.

Appendix 15
256

A decrease in pH reduces oxygen consumption, and at a
pH of 5.5 respiration slows down to 10% of its normal
rate. Oxygen consumption increases if there is a sudden
decrease in salinity, e.g. from 31 to 24 ppt. Oxygen
demand is greater during the spawning season; therefore,
when bottoms are selected as spawning grounds, there must
be enough oxygen to supply the additional amount necessary
during spawning.

Korringa (1952) discussed the various aspects of oyster
feeding. Ciliary action is capable of driving a current
of water through the ostia (gill slits). During passage
through the Ostia particulate matter is filtered off
and wrapped in mucous. This mucous is transported to the
labial palps where the oysters ingest it or reject it as
pseudofeces. Environmental disturbances can stop mucous
secretion, but may not necessarily stop the pumping of
water; therefore, water managers should be aware that the
water flow does not necessarily indicate feeding. The -
mucous feeding sheets are believed to be important in deter-
mining which small particles may be used as a food source.
Korringa (1952) pointed out that MacGinitie (1945) stressed
the need to obtain the small particles because most of the
organic matter is dissolved. Korringa (1952) believed
that the electrical properties of food particles and feeding
sheets are importnt because usitive @olyvalent ions such
as Al++, Ca++, Fe +, Zn++, Hg + and Mg + are caught and
accumulated, whereas the positive monovalent ions like
Na+ and K+ and the negatively charged ions are not.

Cerruti (1941) recorded the stomach contents of Ostrea
edulis in Mar Piccolo, Italy. His findings revealed large
quantities of organic detritus, diatoms and flagellates,
annelid larvae, sand, silt, sponge spicules, mollusk larvae,
eggs and gastrulae of a variety of marine invertebrates,
plant fibers,.pollen grains and smuts from nearby marine
wharfs. Whether all this material was being utilized as
food or not is a matter of conjecture.. It is known that
many things pass through an oyster's digesti've tract
completely unchanged. Because detrital particles are often
covered with bacteria, Nelson (1947) assumed that bacteria
could be an important food source. Galtsoff (1964)
stated that although the energy requirement of certain
filter feeders are known, there is no information available
about the specific foods needed for growth and reproduction.

Oysters are known to feed on plankton. However, it
has been difficult to determine which ones. It is known
that the planktonic genera Rhizosolenia and Chaetoceras
cannot be ingested by the oyster because of size and shape.
Apparently, Chlorella and certain phytoplankters have

Appendix 15
257

antibiotic properties that are harmful to some bivalves,
The "red tide" caused by Gymnodinium breve is known to kill
oysters along the shores of an affected area, Galtsoff
pointed out that analysis of the plankton sampled near the
oyster bar is needed. Sampling of the plankton by using
the vertical haul method is useless because there is no way
to determine which plankton are caught at the water.surface
and which at the bottom near the oyster bar.

Loosanoff and Engle (1947) conducted experiments
concerned with the effects of different concentrations of
micro-organisms on the feeding of the oyster C. virginica.
The micro-organisms used were the green algae, Chlorella
sp.; the diatom, Nitzschia closterium; the dinoflagellate,
Prorocentrum triangulatum; and the euglenoid Euglena
viridis. (Note: Martin (1929) reported Prorocentrum
triangulatum as sometimes the most abundant organism in
the Chesapeake Bay). The experiments showed that there are
rather definite densities at which a micro-organism begins
to interfere with the oyster's ability to feed. In very
heavy concentrations, pumping may cease entirely or large
quantities of pseudofeces may be formed as the oysters
try to clear their gills and palps. Lesser concentrations
of micro-organisms often result in a greater pumping rate
than when the oysters are kept in sea water. Cell size is
important, as illustrated by the need for a greater number
of small Chlorella to produce the same effect as caused
by smaller number of Euglena. Characteristics displayed
by an oyster maintained in a heavy concentration for a
prolonged period of time were (1) the tonus of the abductor
muscle became either totally or partially impaired and (2)
the oyster became sluggish and its response to stimuli
decreased.- It was mentioned earlier that certain plankters
produce antibiotics harmful to oysters. Loosanoff and Engle
(1947) found that the filtrate of cultures containing cell
metabolic products and the CE11S themselves both affected
the oyster by reducing or entirely stopping the rate of
pumping when the oyster was exposed to strong concentrations
of either component. Galtsoff stated that the ideal time
for oyster feeding is when the water is free of pollutants,
the concentration of diatoms and dinoflagellates is low and
the water flow over the bottom is nonturbulent.

So far, feeding of only the adult oyster has been dis-
cussed. Davis (1950) conducted experiments on the types of
organisms that the larvae of C. virginica utilize as food.
He concluded that the types of microorganisms the larvae can
use as food are limited. The most satisfactory organism for
laboratory feeding was Chlorella sp., but it occassionally IL
appeared to be insufficient nutritionally, especially forthe
early larval stages of the oyster. If they reach 125 microns,

Appendix 15
258

however, all continued to grow and metamorphose to adults
on the Chlorella sp. diet.

NEGATIVE FACTORS' OF ENVIRONMENT

Sedimentation is considered by Galtsoff to be a neg-
ative factor of the environment because, in general,
sedimentation affects oyster development adversely. In
the discussion on environmental conditions of the Chesapeake
Bay, sedimentation was one of the factors presented and
should be reviewed for the present discussion. -

Several factors influence sedimentation: periodic
changes in current velocities; turbulence; salinity;
temperature; density and viscosity of water; size, shape,
roughness and specific gravity of the particles; and the
ability of the particles to flocculate. Galtsoff reported
that in both the Rappahannock and the York Rivers of Virginia,
layers of loose sediments, 1 to 2 mm thick, have caused the
surface of shells and rocks to become unsuitable for the
attachment of larvae, therefore resulting in failure of
oyster setting. Sedimentation is a natural occurrence. It
is not particularly harmful until it increases to the degree
that it interferes with reproduction. High sedimentation
rates have destroyed many formerly productive oyster beds
in the United States.

Loosanoff (1961) conducted experiments on the effects
of turbidity on larvae and adult C. virginica. The materials
he used to create turbid conditions were fine silt from
the tidal flats of Milford Harbor; Kaolin (aluminum
silicate), a clay-like substance; powered chalk; cal-
cium carbonate; and Fuller's earth. All of these materials
can be found in estuarine waters.

Under natural conditions, as little as 0.1 g/liter
of silt can cause a reduction of pumping action in the
oyster. However, Loosanoff discovered that one or two of
the oysters appeared to be stimulated by the silt. As
concentrations.of silt increase, reduction in the rate
of pumping increase proportionally. At concentrations of
3.0 to 4.0 g/liter, the average pumping reduction was 90%.
Loosanoff was quick to point out that although a concen-
tration as high as 3.0 to 4.0 g/liter seldom occurs naturally,
it does occur during periods of heavy floods and in areas
of extensive dredging. Whenever the oysters were returned
to regular sea water, they quickly recovered; both the
pumping rates and shell movement returned to normal. The
experiment described so far was of short duration (3 to
6 hours). During a longer experiment (48 hours), when
the oysters were returned to clean water after being

Appendix 15
259

subjected to turbid conditions, they did not demonstrate
the return to normal rates of shell movement and pumping,
indicating that possibly their ciliary mechanisms had been
damaged. Another aspect of this problem is that during
exposure to continuous high temperatures, the oysters are
forced to function at higher metabolic rates. If the water
is turbid, and they are unable to open their shells, they
will die of starvation and suffocation. According to 01
Loosanoff, this result is a logical inference because oysters
keep their shells open from 97 to 99% of the time at tempera-
tures of 20 C and above.

The other substances used by Loosanoff in his experi-
ments produced similar effects in that the pumping rate
was reduced, shell movement became abnormally vigorous
and large quantities of pseudofeces were discharged.
Loosanoff reported on the observations of Harry C. Davis
(unpublished data) with regard to the effects of turbidity
on larvae. Davis demonstrated that at concentrations of
0.25 g/liter of silt only 73% of the oyster eggs survived
and at 0.5 g/liter only 31% survived. At higher ratios,
the survival rate was almost nil. Contrarily, in suspension
of kaolin or Fuller's earth at 1.0 g/liter, nearly all the
oyster eggs developed to the straight hinge stage. Even
at concentrations of 4.0 g/liter some of the oyster eggs
developed. It must not be construed that these substances
aided development, but merely that this result was noted.
These results should be investigated more fully because the
findings may improve handling of larval cultures.

So far, sedimentation has been discussed as a physical
factor. Biologically, certain organisms such as mud-
gathering and mud-feeding invertebrates can cause an ac-
cumulation of silt over oyster bottoms. As an example,
Galtsoff reported that the mud worm, Polydora ligni, was
observed to reproduce so rapidly in Delaware Bay that nearly
every live oyster was smothered by a deposit of mud several
inches thick.

Sedimentation can be created by the oysters themselves.
They are known to discard large quantities of organic sediments
as pseudofeces. Also, the material used during feeding can
be discharged as fecal ribbons at the rate of several
centimeters/hour. This fecal mass, in conjuction with slug-
gish water movement, can result in a contaminated bed. Ito
and Imai (1955) observed a decline in productivity of oyster
beds because of contamination by fecal material. Galtsoff
dontended that the biochemical changes associated with
bacterial decomposition of organic components of sediments
which results in carbon dioxide, ammonia, phosphates,
sulphates and various organic acids plus hydrogen sulphide

Appendix 15
260

and methane formed during anaerobic oxidation, are respon-
sible for the slower growth of oysters on the bottom of
the bed than ones kept above the bottom on trays.

The second factor that Galtsoff considered as a negative
environmental factor is disease. Symptoms for the most part
are nonspecific. Galtsoff listed several symptoms usually
indicative of disease: slow growth; failure to fatten;
failure to develop gonads; recession of the mantle; valves
slightly agaped, probably resulting from a weakened adductor
muscle; abnormal deposition of shell material, which causes
formation of short and thick shells; a watery and discolored
dirty green or brown body; and/or a bloody body with ac-
cumulated blood cells on the mantle and surface.

Galtsoff listed several diseases as affecting oysters.
Among them are the Malp*eque Bay Disease; Dermocystidium
marinum, a fuAgus; a disease associated with Haplosporiduem,
better--known by the acronym MSX; shell disease, thought
to be a fungus; foot disease, another thought by Korringa
to be the same causative agent as shell disease; Hexamita,
a flagellate; Nematopsis ostrearum; and parasitic trematodes
and copepods. The above-m@_n_tioned diseases will not be
discussed to any great extent. The symptoms exhibited by
oysters are reviewed in Galtsoff's work. It should be
noted that several of the "diseases" are caused by organisms
that belong to the community associated with oysters.
For this reason, they will be discussed at greater length
in the following discussion of the oyster bar community.

.COMPONENTS OF THE OYSTER COMMUNITY

The organisms associated with the oyster community
are probably better known than the organisms that make-up
other communities in the Bay. In fact, the oysters and
associated animals hauled up onto a boat deck led Karl
M8bius (1877) to introduce the term biocoenosis
The oyster, the dominant organism, provides a.habitat for
a number of organisms. Wells (1961) listed the various types
of habitats that exist in oyster-dominat.ed areas. The oyster
shell provides a substrate for many encrusting organisms such
as protozoans, sponges, coelenterates, bryozoans, barnacles
and ascidians. Other animals such as many of the annelids,
decapods, amphipods, isopods, insects, pycnogonids,
nemerteans, flatworms, echinoderms.., fishes., gastropods and
sipunculids live between the encrusting organisms or in the
crevices between the shells. Some organisms actively burrow
into the shell. The substrate between or under the oyster
provides a conducive habitat for still more animals. Table
16-13 is a list of organisms found by Wells (1961) during
his study in Newport River, North Carolina, 1955-.56.
Many '6-f the organisms are common to the Chesapeake

Appendix 15
261

TABLE 15-13
FAUNAL COMPOSITION OF AN OYSTER COMMUNITY

Protozoa:

Poreoponides cf. lateralis

Porifera:

Cliona celata
Cliona lobata
Cliona spirilla
Cliona trutti
Cliona vastifica
Dictyociona adioristica
Haliclona permollis
Halisarca
Hymeniacides heliophila
Lissodendoryx isodictyalis
Microciona prolifera
Scypha barbadensis

Coelenterata:

Aiptasia eruptaurantia
Aiptasia pallida
Astrangia astreiformis
Bunodosoma cavernata
Diadumene leucolona
Diadumene luciae
Epizoanthea americanus
Eudendrium carneum
Hydractinia echinata
Leptogorgia setacea
Leptogorgia virgulata
Obelia sp.
Oculina arbuscula
Tubularia crocea

Platyhelminthes:

Bdelloura candida
Euplana gracilis
Gnesioceros floridana
Latocestus whartoni
Oligoclado floridanus
Prosthiostomum lobatum
Stylochus ellipticus

Appendix 15
262

TABLE 15-13 (cont'd)
FAUNAL COMPOSITION OF AN OYSTER COMMUNITY

Nemertea:

Amphiporus ochraceus
Micrura leidyi
Tetrastemma elegans
Tubulanus pellucidus

Mollusca: Amphineura:
Chaetopleura apiculata

Gastropoda: Prosobranchia:

Anachis avara avara
Anachis floridana
Anachis translirata
Bittium varium
Busycon canaliculatum
Busycon carica
Busycon contrarium
Caecum pulchellum
Calliostoma euglyptum
Cantharus tinctus
Cerithiopsis greeni
Cerithiopsis sublata
Cerithium floridanum
Crep dula convexa
Crepidula fornicata
Crepidula plana
Diodora cayenensis
Epitonium apiculatum
Epitonium humphreysi
Eupleura caudata
Fasciolaria hunteria
Hydrobia minuta
Littorina irrorata
Mangelia guarani
Mangelia plicosa
Melanella conoidea
Mitrella lunata
Murex fulvescens
Nassarius obsoletus
Nassarius vibex
Neosimnia uniplicata
Niso interrupta
Pleuroploca gigantea
Rissoina chesnell
Rissoina decussata
Seila adamsi
Thais floridana
Trphora nigrocincta
Urosalpinx cinerea

Appendix 15
263

TABLE 15-13 (cont'd)
FAUNAL COMPOSITION OF AN OYSTER COMMUNITY

Opisthobranchia:

Ancula evelinae
Aplysi morio
Berghia coerulescens
Catriona tina
Chromodoris aila
Corambella baratariae
Cratena kaoruae
Dondice occidentalis
Doriopsilla leia
Doriopsilla pharpa
Hermaea dendritica
Miesea evelinae
Odostomia dianthophila
Odostomia dux
Odostomia impressa
Odostomia modesta
Odostomia seminuda
Okenia impexa
Polycera hummi
Tritonia wellsi
Turbonilla interrupta

Pelecypoda:

Abra aegualis
Aeguipecten irradians concentricus
Anadara ovalis
Anomia simplex
Arca, umbonata
Acropsis adamsi
Atrina rigida
Barbatia candida
Brachidontes exustus
Brachidontes recurvus
Chama macerophylla
Ch one cancellata
Chione grus.
Congeria leucophaeata
Corbula swiftiana
Crassostrea virginic
Cumingia tellinoides
Diplodonta punctata
Diplodonta semias2era
Gemma gemma purpurea
R-iatella striata
Lima pellucida
Lithophaga bisulcata
Lyonsia hyalina
Martesia smithi
Mercenaria mercenaria

Appendix 15
264

TABLE 15-13 (cont'd)
FAUNAL COMPOSITION OF AN OYSTER COMMUNITY

Modiolus americanus
Modiolus demissus
Mulinia lateralis
Musculus lateralis
Mytilus edulis
Noetia ponderosa
Ostrea equestris
Petricola pholadiformis
Pteria colymbus
Rangia cuneata
Rocellaria hians
Rupellarla typica
Tagelus plebius

Annelida: Oligochaeta:

Enchytraeus albidus

Polychaeta:

Amphitrite ornata
Armandia agilis
Autolytus varians
Axiothella mucosa
Capitella capitata
Cistenides gouldii
Dexiospira spirillum
Diopatra cuprea
Dorvillea sociabilis
Eteone heteropoda
Eumida sanguinea
Eunice rubra
Eupomatus dianthus
Glycera americana
Haplosyllis spongicola
Harmothoe aculeata
Heteromastus filiformis
Hypsicomus torquatus
Lepidametria commensalis
Lepidonotus sublevis
Lepidonotus variabilis
Loimia medusa
Marphysa sanguinea
Naineris laevigata
Neanthes succinea
Nereiphylla fragilis
Nereis occidentalis
Petaloproctus socialis
Pista palmata
Podarke nr. guanica
Polydora websteri
Prionospio treadwelli
Pseudopotamilla reniforms

Appendix 15
265

TABLE 15-13 (cont'd)
FAUNAL COMPOSITION OF AN OYSTER COMMUNITY

Sabella melanostigma
Sabella microphthalma
Sabellaria vulgaris
Spiopbanes bombyx
Streblospio benedicti
Terebella rubra
Tharyx setigera
Thelepus setosus

Sipunculida:

Aspidosiphon parvulus
Physcosoma capitatum

Arthropoda: Amphipoda:

Caprella acutifrons
Caprella linearis
Carinogammarus mucronatus
Corophium cylindricum
Gammarus locusta
Jassa marmorata
Melita appendiculata
Melita dentata

Isopoda:

Cassidisca lunifrons
Chiridotea caeca
Cilicaea candata
Cyathura carinata
Dynamene perforat
Erichsonella filiformis
Idothea baltica
Leptochelia rapax
Leptochelia savignyi
Ligia exotica
Limnonria lignorum
Sphaeroma quadridentata

Decapoda:

Alpheus armillatus
Alpheus heterochaelis
Alpheus packardi
Callinectes ornatus
Callinectes sapidus
Cancer irroratus
Clibanarius vittatus
Eurypanopeus depressus
Heterocrypta granulata
Hexapanopeus angustifrons

Appendix 15
266

TAME 15-13 (cont'd)
FAUNAL CONPOSITION OF AN OYSTER COMMITY

Hippolysmata wurdemann-i
Hippolyte Pleurocantha
Libinia dubia
Libinia emarginata
Menippe mercenaria
Metoporhapis calcarata
Neopanope texana sayi
Neopanope sp.
Neopontonides beaufortengis
Pachygrapsus transversus
Pagurus longicarpus
Pagurus pollicaris
Palaemonetes intermedius
Palaemonetes pugio
Palaemonetes vulgaris
Panopeus herbsti
Pelia mutica
Penaeus aztecus
Petrolisthes izalathinus
Pilumnus dasypodus
Pilumnus lacteus
Pilumnus sayi
Pinnixa cylindrica
Pinnotheres ostreum
Plagusia depressa
Porcellana soriata
Portunus sp.
Rithropanopeus harrisi
Sesarma cinerea
Sicyonia laeviGata
Synalpheus townsendi
Thor floridanus
Uca pugilator

Cirripedia:

Alcippe lampas
Balanus amphitrite niveus
Balanus eburneus
Balanus improvisus
Balanus tintinnabulum
Chthamalus fragilis

Insecta:

Anurida maritima

Pycnogonida:

Anoplodactylus lentus
Nymphon ubrum
Tanystylum orbiculare

Appendix 15
267

TABLE 15~-13 (cont~d)
FAUNAL COMPOSITION OF AN OYSTER c~qo~8qMT~qI~%~TITY
X~qiphosurida~:

L~qimulus Polyphemus

Bryozoa--Entoprocta:

Pedicellina cernua

Bryozoa--Ectoprocta:

Aeverrillia setigera
Alcyon~q-I~8qT~qI~q-um ~6qhauf~qf
Alcyon~f~q-~6qd~q-~l~qum ~q-p~q-~o~4ql~q-~qy~6qm~2qm
Amath~qi~q5~q@~q-~qconv~q-o~8q=~4qT~4q=
A~r~nathia distans
Anguine~q-l~qia pa~qlmata
Bower~0qU~0q=a~qna7~q-g-r~q-a~2q=~cis
Bugul~-a-~qc~0q=af~q-o~qf~0qf~0qn~q-~2qf~q-~qca
Bugul~q-a ner~ql~2qt~qi~-~qn~q-a
~2qTr~q-~qy~-~qp~- ~8qT ~-o~- s~q-u I -a- ~-~qP =a a s i a n a
E 1 e c t r ~0qT~q-~c ~qr u~-s~-~qt~-u~-~ql~-e-n-~qt~0q=
Electr~qd ~6qhast~qings~0qTe~-~q-
Memb~0qFa-n~qipora te-n~u~~qls
Microp~q-~o~qr~q-~0q=ea ~q-~c~8qTI~8qT~-a~-ta
Nolella~q--~-s~2q=p~qdta
~qFarasm ~qt~-~6qf~n~q-a~q--~6qMspinosa
~qSch~qlzop~q-~qo~q-r~0q=e~qg corn~6qa~6q=
~qSchizo~qpore~qi~qla un~qic is
Victore~2qlla ~qpavida

Ech~qinodermata:~

Arbac~qia punctulata
Asterias forbes~8qT~q-
Lytechinus var~qi~-~8q6gatus
Ophiothri~qx angu~qlata
Thyone ~qbr~qiareus

Chordata: Urochordata:

Ascidia interrupta
Didemnum lutar~qium
Molgula manhattens~qis
Perophora vir~ql~2qU~8ql~q-s
Styel plicat~6qF~q-

Vertebrata:

~-Ancylopsetta quadrocellata
Chaetodipterus raber
Chasmodes bosqu~4qianus
Fundulus ma~8qjalls
Gobiesox v~4qirgu~2ql~q'~56qdtus

Appendix 15
268

TABLE 15-13 (dont'd)

FAUNAL COMPOSITION OF AN OYSTER COM MUN ITY

Gobionellus boleosoma
Gobiosoma bosci
Hippocampus hudsonius
Hypleurochilus geminatus
Hypsoblennius hentz
Opsanus tau
Orthopristis chrysopterus
Paralichthyes dentatus
Synodus foetens

Appendix 15
269

Bay area, but others are not. Wells' study was in the
Beaufort area of North Carolina, a geographic location
noted as the demarcation line between northern and southern
species. An extremely rich fauna is found here because
of the overlap between the two regions.

Not every animal within the oyster community will be
discussed, but the more important ones will be mentioned as
to their affect on the community sturcture as a whole. In
addition, references will be made to important papers that
water managers should be aware of for their context of
oyster bar locations within the Bay and for the organisms
associated with the bars.

Frey (1946) wrote a report concerning the oyster
bars of the Potomac River for the U.S. Fish and Wildlife
Service of the Department of the Interior. In this
report, he described the bars of the Potomac.and reviewed
their past history. It is an important document from a
historical perspective and for information that managers
could apply to their programs.

Frey (1946) reported that oysters can be found from
the mouth of the Potomac to Maryland Point, a distance of
61 miles. At the time of his report, however, commercial
oystering was conducted from Lower Cedar Point downstream.
The river was fairly free of oyster enemies. Frey (1946)
reported observations of Polydora websteri, the mud worm;
Cliona truitti, the boring sponge; Pinnotheres ostreum,
the oyster crab; Bucephalus, the trematode worm, and
there was a high probability that the parasite Nematopsis
was present, but it was not found.

Although Frey's (1946) study was primarily a survey,
he also collec 'ted most of the organisms he encountered
with the oysters, preserved them and then transferred them
to the collections of the National Museum of Natural History.
Table 15-14 lists the organisms Frey found associated with the
oysters in the Potomac River.
Table 15-15lists the organisms found in the York River
by Galtsoff, Chipmon., Engle and Calderwood (1947). As in
Frey's (1946) study, not all inhabiting organisms were col-
lected and identified, but only those organisms which were
intimately associated with the oyster or which constituted
a definite danger to them were reported.

Table 15-16 is the lastlist used to illustrate the oyster
community structure of the Chesapeake Bay. This list was
taken from Merrill and Boss's (1966) work on the lower
Patuxent' River in Kirylafid. Merrills Emery and Rubin (1965)

Appendix 15,
270

TABLE 15-14
ORGANISMS OBSERVED ASSOCIATED WITH OYSTER BARS
IN THE POTOMAC RIVER (From Frey, 1946)

Sponges

Microciona prolifera
Haliclona permollis
Cliona truitti

Coelenterates

Clytia longicyatha
Thuiaria argentea
Bimeria tunicata
Anemones (unidentified but abundant)
Dactylometra quinquecirrha

Ctenophores (not collected for identification)

Mnemeopsis sp.
Beroe.sp.

Flatworms

Stylochus ellipticus
Bucephalus sp.

Nemerteans

Micrura leidyi

Bryozoa

Acanthodesia tenuis
Membranipora crustulenta

Polychaete worms

Neanthes succinea
Polydora websteri
Nereis culveri
Scolelepis viridis
Nereiphylla fragilis

Leech

Homibdella sp.

Appendix 15
271

TABLE 15-14 (cont'd)
ORGANISMS OBSERVED ASSOCIATED WITH OYSTER BARS
IN THE POTOMAC RIVER (From Frey, 1946)

Amphipods

Carinogammarus mucronatus
Corophium lacustre
Grubia compta
Melita nitida
Gammarus sp.
Caprella acutifrons

Isopods

Cassidinidea lunifrons
Erichsonelia attenuata
Cyathura carinata

Decapods

Palaemonetes carolinus
Pakaemonetes vulgaris
Crangon septemspinosus
Pinnotheres ostreum
Eurypanopeus depressus
Rhithropanopeus harrisii
Callinectes sapidus
Sesarma cinereum

Molluscs

Odostomia trifida
Nassarius vibex
Littori irrorata
Crepidula convexa
Melampus lineatus
Epitonium lineatum
Mya arenaria
Brachidontes recurvus
Volsella demissa
V. papyria
Mulinia lateralis
Congeria leucopheata
Arca campechiensis
Macoma balthica
Tellina tenera
Gemma emma manhattensis
Corambella sp.

Tunicates

Molgula manhattensis

Appendix 15
272

TABLE 15-14 (cont'd)
ORGANISMS OBSERVED ASSOCIATED WITH OYSTER BARS
IN THE POTOMAC RIVER (From Frey, 1946)

Spermatophytes

Potamogeton pertinatus
Potamogeton perfoliatus
Ruppia maritima
Zostera marinus

Algae

Ulva sp.
Enteromorpha sp.
Polysiphonia
Ceramium
Dasya
Gracilaria

Appendix 15
273

TABLE 15-15
ORGANISMS FOUND IN ASSOCIATION WITH OYSTERS INTHF YORK RIVER
(From Galtsoff, Chipman, Engle and Calden,@,ood, 1947)

Sponges

1. Cliona celata - sulfur sponge (boring)
2. Microciona prolifera - red-bearded sponge

Coelenterates

3. Thuiaria
4. ylometra quinquecirrha
5. Cyanea sp.
6. elia sp.
7. Sea anemones were seen on many shells and oysters
brought in from all parts of the river.

Ctenophores

8. Mnemiopsis gardeni: several other species observed.
9. Unknown turbel-i-a-rTan worm

Nemerteans

10. Cerebratulus lacteus
11. Bryozoan colonies

Annelids

12. Nereis limbata Ehlers - clam worm
13. Hyd oides hexagonus
14. Polycirrus eximius
15. Polydora ligni Webster
16. Polydora calca Webster
17. Polydora sp. - probably anaculata Moore

Arthropods

18. Eurypanopeus dissimilis - mud crab
19. Panopeus herbstii - mud crab
20. Neopanope texana texana mud crab
21. Rhithr9panopeus harrisii mud crab
22. Callinectes sapidus
23. Hermit crabs
24. Libinia dubia and L. emarginata - sp-ider crabs
25. Fiddler crabs
26. Ocypode albicans - sand crabs
27. Barnacles
28. Pinnotheres ostreum. - oyster crab

Appendix 15
. 274

TABLE 15-15 (cont'd)
ORGANISMS FOUND IN ASSOCIATION WITH OYSTERS IN TTT@ YORTI, RP77
(From Galtsoff, Chipman, Engle and Calderwood, 1947)

Gastropods

29. Nassa sp. - mud snail
All 30. Littorina
31. Urosalpinx or Eupleura
32. Polynices sp.
33. -Busycon carica
34. B. canaliculatum
35. Purpura
36. Crepidula
37. Modiolus demissus - horse mussel
38. Mytilus edulis - mussel
39. Ensis directus - razor clam
40. Diplothyra - boring clam
41. Asterias forbesi - starfish
42. Tunicate Molgula sp.

Appendix 15
275

TABLE 15-16
BENTHIC FAUNA IN LOWER PATUXENT RIVER, MARYLAND

DM
10
ORGANISM NUMBERS OF INDIVIDUALS PER 5-MINUTE TOW
STATION I z 3 4
F,
x (depth, ft.) (130) (65) (16) (130) (65) (10)
@-j Porifera,
Ln

Wcrociona olifera
(Ellis 4 - - - abundant

Coelenterata

Aiptasia eutauran'tia, (Field) 400 - 52 308
Aiptasimorpha. luciae-TVerrill) - 4
Diadumene le" olena CVerrill) - 2 - 66
Thuiarla arizentea (Linnaeus) - - - some - -

Annelida,

Nereis (Neanthes) succinea. - 5 S4 32 114 122
(Frey & Leuck tT-
Polydora ligni Webster
Mllodoce -aitides) maculata. 6 11
(Linnaeus
Glycera. dibranchiata Ehlers 2
Polyclad worms 3 3

Crustacea

Balanus improvisus Darwin many many
%Ta-nus eburneus (Gould) COMOn common
Ca-Flinectes sa idus Rathbum common common - rare rare
Eurypanopeus us (Smith) 4 - - -
Rithropanopeus harrisii (Gould) 8 101 1 23 66 52
36 12 - 12 2 -

NOTE: Stations 1, 2, 3: June 1964,
Stations 4, 5, 6: December 1964

TABLE 15-16 (cont'd)
BENTHIC FAUNA IN L014ER PATUXENT RIVER, MARYLAND

ORGANISM FUMBERS OF INDIVIDUALS PER 5-MINUTE TOW

STATION 1 2' 3 4 5 6
(depth, ft.) (130) (65) (10) (130) (65) (16)
Cjpgon septempinosus (Say) 2 - - 7 -
Va-laemonetes u io Holthuis - 6 - -
Falaemonetes Wgaris (Say) - 1 10
PalaemonetFs- Intermedius Holthuis .6

Mollusca.

Nassarius vibex (Say) 6 1 18
@m (Kurtz) 16 - 2
. @um 'rupicola
Udostomia 1@2ressa (Say) - 2 - -
ZMstomia bisuturalis LW) - - - - 4
Hardnoea olitaria (S"ay) - 34 - -
Crassostrea. virginica. (Gmelin) 2S8 1677 227 49 10S8 162
Tr-a-H-clidontes recurvus (Rafinesque) 1004 1356 47 51 S46 62
%-1-1m-a lateralis (Say) - - - - S
I-7o-tten) - - 12
La (Linnaeus) 3 18 4
W 41
Tagelus ple ius (Solander) - -
Macoma h`YFUH-ca (Linnaeus) 5 8 1
Laevicardiinn mortoni (Conrad) 1 -

Tunicata

Molgula manhattenensis (DeKay) 200 120 5 30,000 648 293

Pisces

10 Gobiosoma bosci (Lacepede) - 6 4 3 2 1
Wlesox strtmosus cope - - 2 1 2 -
ChasmoTe-s (Lacepede) - - 1 1 6 1
9L 'E@Uanus
Opsanus tau (Linnaeus) - - 3 3 2 -
Sy@nathus fuscus Storer - - - 3 2

estimated that., in the Chesapeake Bay, six meters is the
average depth at which oysters are found. In the vicinity
of Point Patience in the lower Patuxent, oysters were
found at a depth of 120 to 130 feet. This depth differ-
ence prompted Merrill and Boss's (1966) study. They estab-
lished three stations: at 104, 65 and 130 feet. They sa mpled
each station twice, in June and December, 1964 (Table 15-16).

Merrill and Boss's work can be utilized to determine
some aspects of depth limitation and seasonal cycles of
certain organisms, but it will take more sampling to firmly
establish any conclusions.

The three tables presented can be utilized by
water managers in determining the common occurrence of
organisms within the oyster community. They also represent
three distinA locations in the Bay, therefore increasing
their value. An idea of the type of organisms associated
with oysters should now be apparent.

Galtsoff (1964) discussed the commensals and competi-
tors that are a part of the oyster community's make-up. '
To avoid confusion in terminology, the same terminology will
be used as that Galtsoff used. His definition of a commensal
is an "organism which stores food gathered by the host."
Parasites "live 'at the expense of their host and sometimes
inflict serious injury .11 "Competitors are organisms which
live in close proximity to one another and,struggle for
food and space available in the habitat."

One of the most,common animals associated with sponges
is the boring sponge; there are seven species of Cliona
found along the Atlantic coast. Almost a@l oyster bottoms
are affected to a certain degree by sponges. In a heavy
infestation, the oyster shell will become brittle and break
under the slightest pressure. Species identification is
based on type of cavity formed by the sponge and by the
type of spicules present.

Although the boring sponge does not derive nourish-
ment from the oyster body, it may from the shell.
Apparently this sponge has cytoplasmic filaments which
penetrate calcite by secretion of minute amounts of
acid. The excurrent canal of the sponge carries out the
fragments that break off the shell. The oyster generally
is able to deposit shell material quickly enough to prevent
the sponge from actually contacting its body. However, if
the sponge does come in contact with the body of the oyster,
there is a lysis of the epithelium and underlying connective
tissue. Obvious features are dark pustules on the oyster
tissue opposite the shell h6les, flabby tissue and a mantle
easily detached from the shell surface.

Appendix 15
278

Diplothyra smithii., better known as the boring clam.,
has a distribution from Cape Cod (Provincetown, Massachu-
setts) to Florida, Louisania and Texas. Galtsoff has col-
lected specimens from dead oyster shells around Tangier
Sound in the Chesapeake Bay. As with the boring sponge,
the boring clam rarely comes in contact with the oyster's
tissues because the oyster keeps,depositing layers of con-
chiolin over the areas that are nearly perforated. The
presence of the clam is indicated by a small hole. The
main effect of this organism on the oyster is the weakening
of shell structure.

Mud worms were mentioned earlier in the discussion of
Frey's survey in the Potomac River. The two that affect
the oyster are Polydora websteri and P. ligni. P. websteri,
found inside the shells or on the inner surface near the
valve, builds a U-shaped tube from accumulated mud. The
oyster secretes a semi-transparent shell material over
the tube, forming a blister. P. websteri is not considered
to cause visible injuries although Loosanoff believes
that heavily infested oysters are generally in poor con-
dition; therefore, it is not beneficial nor neutral in
its effects on the oyster (Loosanoff and Engle, 1943).

P. ligni makes U-shaped or straight tubes by holding
together mud particles with a mucous secreted by the
antennae and body surface. These mud worms become de-
structive when they become so numerous that they smother
the oyster population with their-shells.

The oyster crab, Pinnotheres ostreum, is abundant,
especially in the Virginian part of the Bay. This crab
enters the mantle cavity.of the oyster when its carapace
is 0.59 to 0.73 mm long. Although male crabs do not perman-
ently attach to the host, the females remain attached,
especially in various part-s of the water-conducting system.
The crabs can cause a form of "lesion" on the oyster gills
which impairs their function. Severe lesion cause leakage
from the water tubes and a reduction in the efficiency
of the food-collecting apparatus and gills. Oysters, for
the most part, are able to rapidly regenerate damaged
gills; however,'infestation interferes with gill function
and causes the oyster to be in poor physical condition.

Spirochaetes are bacteria, often found in the crystalline
style sac of the oyster and in the gonads after spawning.
Dimitioff (1926) identified ten spirochaetes'found in oysters.
They are Saprospira grandis.,-�.-lepta,'S, puncta, Cristispira
balbiani,, C. anodontae, 'C-* 's-RI" u'li'fe*ra,, C. modiola C. mina,
C. tem, and Sgirillum ostrae, Of the oyi-ters in tte-Bal-ti-
more area, 91% were affected. Apparently these organisms are
harmless to man and oysters.

Appendix 15
279

Occasionally in shallow bays and estuaries oy sters
are infested by a perforating alga. In most cases, this
alga is Gomontia polyrrhiza, which is distributed from
North Carolina to Connecticut and on up to New Brunswick,
Canada. It does not appear to be harmful to the oyster except
possibly for causing the,greenish color found on the inner
surface of the valve. Continuous growth of the algae in em-
pty shells is thought to accelerate the shell's disintegration
and return calcium salts to the sea.

So far the organisms that have been discussed live
within the oyster shell. There are also numerous organisms
that utilize the shell as a convenient place for attachment.
The effect these organisms have on the oyster is that they
compete for food and space and have been known to accumulate
to such an extent that they actually smother the oysters.

One of these fouling organisms is the slipper shell,
Crepidula fornicata, which attaches to hard objects near
or below low water. Crepidula and the gastropod Anomia
have both been observed in the Chesapeake Bay (Beaven, 1947).
However, they are not serious fouling organisms as far as
the Chesapeake Bay is concerned (Beaven,,1947). Generally
they are limited to salinities above 15 PPt-

Molgula manhattensis, the sea squirt, has been observed
so popuious in the Ch-e-s-f-er River, Maryland, that they hide
the oysters. Beaven (1947) reported that, although they
interfere with harvesting, they do not interfere with setting.
If heavy aggregations die en masse in the late winter or
early spring, the decaying animal matter may form a
smothering deposit, killing the oysters underneath.

Barnacles are more abundant at salinities under 20 ppts
but can be found throughout the Bay (Beaven, 1947). The
setting of the barnacle Balanus improvisus was reported
in Broad Creek, in Talbot County, Maryland by Shaw (1967).
In higher salinities, the barnacles are either killed by
drills or have to compete with sponges and other organisms.
Beaven (1947) reported two periods of intense setting of
barnacle larvae. 'The first set occurs in April or May and
the second in November or December. In either case,
the setting peaks when the water temperature is about 15*C.
The setting of the barnacles can interfere with the setting
of the oyster spat. Oyster spat may attach to barnacles
if there is not a natural surface available, but the setting
efficiency is greatly decreased.

Galtsoff observed that the appearance of bryozoans
usually preced 'e the time of oyster setting, making the
oyster shell surface unsuitable for the setting of spat.

Appendix 15
280

The bryozoans Acanthodesia tenuis and Membranipora
crustulenta occur throughout the oyster-producing waters,
but are especially abundant at 10-18 ppt salinity (Beaven,
1947). Setting of the bryozoans occurs when the water tempera-
tures are 200C or higher. Because the setting occurs pri-
marily in late summer, the oyster sets are not interfered'
with until then. Beaven (1947) also stated that it was
fortunate that the bryozoans do not thrive in the oyster
seed areas. In the Solomons area, Beaven (1947) observed
a decrease in the late summer setting . spring-planted
oyster shells; therefore, he suggested a delay in shell
planting until sure of an imminent oyster set. Shaw
(1967) suggested the placing of shells or asbestos
plates in July to avoid fouling that occurs in the spring
by several organisms, including the bryozoans Electra
crustulenta and Membranipora tenuis.

In Broad Creek, Maryland, Shaw (1967) reported that the
mussel Branchidontes recurvus is a fouling organism of
oyster shells. Beaven (1947) stated that mussels are
common in the upper Bay and tributaries where the salinities
are low. He observed one bar comprised of one-half oysters
and one-half mussels. Such a condition decreases oyster
production. The bivalve Mytilopsis is commonly found on the
oysters and cultch in the lowermost salinities where oysters
occur (Beaven, 1947). Galtsoff (1964) observed that with
the exception of the mussel Mytilus edulis, most fouling
organisms die off in the winter. Mytilus edulis has been
known to cover an oyster bed with a thick layer of mud and
excreta.

Annelid worms live between oyster clusters and/or
in the shells. Galtsoff reported that Hartman (1945)
listed seven species of worms found between clusters of
living oysters. Korringa, (1951) observed 30 species in
Dutch water. Beaven (1947) noted that in salinity ranges
above 15 Ppt serpulids could be found; they can easily be
recognized by their calcareous tubes. The sabellids or
membranous tube worms have a more general distribution
Bea'ven stated that generally the worms are not harmful: but
occasionally Sabellaria has been observed encrusting shells
with deposits an inch or more in thickness. These deposits
prevent the attachment of the spat and smother the oysters.
The locations where such deposition has occurred are where
the bottom is comprised of fine sand or silt and the wave
action keeps it in suspension over the bed. The worms use
the material from the heavily laden water for building their
tubes.

Beaven (1947) found that encrusting sponges are
abundant among the deeper rocks of Tangier Sound during the
fall when the salinities are above 20 ppt. These sponges.

Appendix 15
281

make harvesting difficult and also smother some spat and small
oysters. The boring sponges are common at hither salinities.
After an area has been prepared by shell deposition to at-
tract spat, the sponges do not seem to have much effect the
first season, but cause decline in productivity in succeeding
seasons. Galtsoff (1964) observed that the red sponge Micro-
ciona prolifera is often found in highly productive oyster
arei-s.

Folliculid protozoans are often found on clean shells.
They are present year round. Beaven (1947) reported that
they do not appear to affect oyster setting or survival.
Andrews (1915) recorded a mass occurrence in the Chesapeake
Bay.

Galtsoff (1964) reported on the different types of
algae that have been known to attach themselves to oyster
shells. Among those mentioned as affecting oysters are
Enteromorpha, Ulva, Griffitsia, Ceramium, Chondria, Champia
and Scytosiphon. Gracillaria confervoides has been known
to sometimes completely cover an oyster bottom.

Seaweeds also often cover oyster bottoms. One such
seaweed is 'Zostera marina which was previously discussed
in detail. One seaweed., knownas the "oyster robber"
(Codium fragile), was introduced to Cape Cod waters with
oTsters from Peconi Bay, Long Island, New York. On sunny
days, the branches of the seaweed fill-up with gas produced
by photosynthesis. The gas-filled branches float up and
out with the tide, carrying off the oysters to which they
were attached. Another seaweed of particular importance to
the Chesapeake Bay is the Eurasian watermilfoil, Myriophyllum
spicatum, which became established on the Maryland and
Virginia sides of the Potomac River in 1933. Since then its
distribution has increased to more of the Bay. This plant
became a problem when it died after a period of spectacular
growth. The decomposing leaves and stems smothered the
oyster by using up available oxygen necessary for the de-
composition process.

Beaven (1947) noted an organic film often found on
oyster shells. This film consists of diatoms, algae,
bacteria, other small organisms and silt. It usually
develops over most of the shell surface. It can cause
a decrease in the number of fouling organisms and-spat
that may attach, and in fact, has been observed to accu-
mulate so heavily it can be peeled off in sheets.

So far in considering the oyster community, only the
commensals and competitors have been discussed. Now
attention must be turned to the predators., those organisms

Appendix 15
282

which utilize the oysters as food. Oyster predators include
flatworms, mollusks, echinoderms, crustaceans, fishes., birds,
and mammals.

Among the carnivorous gastropods that feed on oysters
are Urosalpinx cinerea, Eupleura caudata, Busycon carica,
and ff. canaliculatum. Urosalpinx cinerea. has a distribution
range from Canada to Florida. Its migration rate is limited
in that it can average, under its own power, 15 to 24 feet
a day in the direction of food. This distance can be in-
creased if it attachs to floating debris or to organisms,
such as the hermit and horseshoe crabs. This drill, Urosal-
pinx, is particularily detrimental to young oysters.
Galtsoff stated that between Chincoteague and Cape Charles
oyster drills have killed 60 to 70% of the seed oysters
and in certain locations have killed the entire crop.
Urosalpinx cinerea. is limited to some extent by the com-
bined influence of the salinity and temperature factors.
At summer temperatures, the minimum survival salinity varies
from 12 to 17 ppt. Given a choice between barnacles and
oysters, the drill seems to prefer barnacles.

The drill Eupleura caudata is less abundant than
Urosalpinx cinerea, but is found in the same waters.
MacKenzie (196-1T-reported that E. caudata becomes active
in the York River when the temp@_rature goes above 100C.
It starts spawning in May when the water temperature reaches
18* to 200C and peaks in June or early July as the water
temperature reaches 210 to 260 C.

The whelks Busycon carica, and B. canaliculatum. are
common in the shallow Atlantic coast waters. Occasionally
they attack oysters. They get inside the oyster by a com-
bination of chipping the oyster shell with the edge of
their shell and by the rasping action of the radula.

Odostomia, are small parasitizing snails which
congregate at the edge of the oyster shell. When the
valves are open, the snail extends its proboscis to the
edge of the oyster mantle where it feeds on mucous and tis-
sue. It is not c -onsidered a particularily important
nuisance. Two species that have been reported as associated
with C. virginica are Odostomia bisuturalis which ranges
from New England to Delaware Bay and 0. impressa, which
ranges from Massachusetts to the Gulf of Mexico.

The starfish Asterias forbesi is a highly destructive
predator of the oyster. This predator is usually found in
waters of high salinity and is not found in brackish water.
Galtsoff reported that salinities of 16-18 ppt represent
the limits of distribution of'Ast'e@r'i:as. This predator

Appendix 15.
283

can be controlled by mopping, dredging or by dispersing
chemicals such as calcium oxide to kill it.

"Oyster leeches" are flatwoTms that are oyster and
barnacle predators. The flatworm that managers of the Chesa-
peake Bay are primarily concerned with is Stylochus elli-
ticus. The predatory activity of S. ellipticus is retarded
at temperatures below 100C. Salinit 'ies as low as 5 pPt
cause only a temporary pause in activity (Landers and Rhodes,
1970). Webster and Medford (1961) observed a high predation
correlation between the worms and oyster spat. Landers
and Rhodes (1970) came to the same conclusion although
they reported a worm 20 mm long killed an oyster 61 mm
long in the Tred Avon River. The collections made by
Webster and Medford (1961) occurred in the Maryland sector
of the Bay. The greatest numbers were reported off the
oyster beds in the lower Potomac.

Landers and Rhodes (1970) reported,that S. ellipticus
is a predator of either oysters or barnacles, but not
both. Scientists of the Virginia Institute of Marine
Science were unable to induce the worm to oyster predation,
but they did prey on barnacles and several species of bi-
valves. At Cape Charles where salinity averages 27 PPtq
the woTms.prey on barnaclesbut in the Tred Avon River where
salinity averages 9-12 ppt, it preys on oysters. Landers
and Rhodes were not able to determine the discrepancy in
food sources. This difference needs to be researched
in greater detail.

Other predators of oysters that deserve mention are
the blue crab (Callinectes sapidus), the common rock crab
,(Cancer irroratus) the green crab (Carcinides moenas).
G@Tl-tsoff (1964) iTtated that although there was not any
evidence that the crabs were attracted to oysters, they
have been observed destroying many small oysters by
cracking the oyster's shell. Mud prawns or burrowing shrimp
and fish also represent predators. Mud prawns belonging
to the genera Upogebia and Callianassa evacuate deep burrows
under oyster bars. It is known that oysters of the genus
Ostrea lurida have been destroyed by material thrown-up
by the mud prawns during burrowing. The black drum fish,
Pogonias cromis., has been observed feeding on both mollusks
and oysters by crushing the shells between their p Iowerful
pharyngeal teeth.

Galtsoff did not give specific examples of birds on
the Atlantic coast that utilize oysters as a food source,
but he did report on birds of the Pacific coast. Among
the examples he gave were the bluebills and white,-winged
scoters.

Appendix 15
284

Galtsoff discussed disease in connection with negative
environmental factors. It was stated earlier that those
organisms that cause disease would be discussed when the
oyster community was described. One of the organisms men-
tioned as a causative agent of disease was the fungus
Dermocystidium marinum. The distribution of this organism
has been reported from Delaware Bay to the Gulf of Mexico.
Andrews (1965) experimented with this fungus in the Chesa-
peake Bay. He determined that in the 1950's D. marinum
was prevalent in all the areas of the Bay where the salinity
was above 15 Ppt. It requires a temperature above 250C
to proliferate readily. It causes mortalities in Virginia
from July thorugh October. Infections can persist into
December, but its effects become subclinical until the
following June or July. Some facts about the disease and
some suggestions to water managers concerned with oysters
were:

1. This organism is density dependent; therefore,
it requires several years to become epidemic on isolated,
disease free or fallowed beds. Short rotation of crops
(as in agriculture) with regular harvesting and inten-
sive clean-ups of beds will greatly limit damage by
the fungus.

2. Less than 10% mortality occurred in oysters
from disease-free low salinity locations in the
first summer. 1

3. Private beds of oysters demonstrated more
D. marinum than sparsely populated public beds.

4. Those areas where oysters do not normally
reside, such as isolated private grounds which are
harvested regularly, do not have losses as great
as plantings near natural oyster reefs.

5. If a bed were allowed to become fallow,
(until nearly all the oysters were dead) and then
replanted, the epizootics would be slow to develop.

It was interesting to *note that dyinginfected oysters in
proximity to healthy oysters hasten the development of
the disease. Andrews (1965)'observed that since the
appearance of the disease MSX, D. marinum. has most'
been eliminated as a cause of oyster mortality. It has
a slightly greater tolerance of low salinities that allows
it to persist along the fringe of the MSX range. However,
if MSX research leads to the development of a means of
eradication, D. marinum@-could become a pr6blem-again.

Appendix 15
285

The disease MSX is associated with a Haplosporidium.
(Haplosporidia is one of 4 subclasses of Sporozoa, a class
of the phylum of Protozoa). This organism invades the
connective tissue surrounding the intestine and digestive
diverticulum. Andrews (1966) characterized the disease in
the Chesapeake Bay by its occurrence in waters above 15 Ppt
and its continuation of activity in the absence of appreci-
able oyster populations. Andrews and Wood (1967) reported
that the disease kills during all seasons. Infections occur
during the five warm months of the year and have variable
inoculation periods. Infections have not been obtained in
the laboratory. A classification has been developed for
the type of infections in various localities in the Bay
by Andrews and Wood (1967). The authors attempted to deter-
mine the origin of the disease, but for the most part the
origin still remains obscure. It is speculated that a
large scale importation of oysters from Virginia's sea-
side into Delaware Bay in thb. 1950's may have provided the
circumstances needed to produce a virulent race of MSX.
Because Virginia's seaside does not appear to be a favor-
able location for the diseaseit is postulated that salinities
close to oceanic salinities may be an inhibiting factor. ,
Puzzlement about the disease arises because some populations
in the infested areas do not appear to be affected. There
may possibly be some sort of resistance.

Galtsoff (1964) listed a shell and a foot disease.
The shell diseasetthought to be caused by a branching
fungus which causes green or orange brown warts on the
inner surface of the shell,is not'very important in C.
virginica. The foot disease is thought by Korringa to be
the same as the shell disease (Galtsoff,, 1964). Whether
or not they are one and the same, the foot disease caused
by fungus affects the attachment of the adductor muscle.
In advanced cases the muscle may become detached from the
shell. This organism has been found in C. virginica,
particularily in the muddy waters of the uthern states.
It is not considered a serious problem.

The flagellate Hexamita and the vegetative stage of the
gregarine Nematopsis"probably should be mentioned. Neither
organism is considered to be a major problem to the oyster.

The trematode Bucephalus haimeanus has been found in
C. virginica. Cheng and Burton (196-5-Fconducted a study
on the relationship between this trematode and C. virginica.
However, they did not identify Bucephalus to species. Areas
reported by Cheng and Burton as sites of infection in the
Chesapeake Bay were Lambstone Bar, upper Tangi6rs Sound, and
Hooper Strait Bar in Maryland. In the Virginia part of the
Bay, Egg Island Bar near the York River was reported to be
infected by the trematode. Trematode sporocysts were found

Appendix 15
286

in the area occupied by the gonad, but there were few or
none in the digestive gland. Oysters collected in Niniget
Pond, Washington County, Rhode Island, demonstrated in-
fections primarily in the spaces between the digestive
diverticula? At.sporocysts increase in size they may
infiltrate the connective tissue enveloping the digestive
tract and then later spread to gonads and other tissue.
Cheng and Burton (1965) made no,.statements regarding mor-
talities of C. virginica caused by Buce2halus, but the
extensive tissue damage the trematode causes cannot help
but impair the oyster's health.

A group of organisms often not considered when one
considers a community is the bacteria. Lovelace, Tubiash
and Colwell (1968) studied Marumsco Bar where oyster
mortalities occur annually and Eastern Bay, a productive,
commercial oyster area. Qualitative differences were ob-
served between the two areas. In Marumsco Bar, there was
greater abundance of Vibrio and Pseudomonas than of
Cytophage/Flavobacterium. The bacteria Achromobocter,
Corynebacterium.Micrococcus,Bacillus and enterics were
approximately equal in both areas. Vibrio and Pseudomonas
appear to be more dominant in late spring and early autumn,
and as far as the Marumsco Bar samples were concerned, they
were dominant especially in the water and in the animals.
Vaughn and Jones (1964) in their bacteriological survey of
an oyster bed in Tangier Sound, showed the bottom samples
consistently contained higher coliforms than the overlying
water.

The final predator to be discussed is the one that
represents the top of the food chain, namely man. Although
man is not part of the oyster community, the oyster is part
of his because he can control the energy flow of the oyster
to a large extent. Oysters represent both a commodity and
a food source to the human species. Our actions probably
affect this population more than those of any other organism.
Bars have been destroyed and/or condemned because of mankind's
pollution, e.g. bars in the upper Bay near Baltimore,
on the other handbars have been "built up" by those
interested in farming oysters. Galtsoff (1964) made a
statement that I feel should be emphasized: "A balance
between the needs associated with industrial.progress and
population pressure on one side and effective conservation
of natural aquatic resources on the other can and must
be found."

APPendix 15
287

POLLUTION

The oyster is a sedentary animal, meaning that it
stays in one location. It does not have a means of loco-
motion to assist it in escaping predators or contaminants
dissolved in the water. Because of this lack of mobility,
there is a great concern both by commercial watermen and the
Public Health Services about the quality of the water flow-
ing over the bar. Galtsoff (1964) recognized two types of
pollution common to oyster beds: domestic sewage and In-
dustrial wastes. Pesticides represent a third type of
contaminant, presently of increasing interest.

Untreated domestic sewerage affects oysters in one or
all of three ways: 1) the sludge can be of such quantity
that it covers the oysters; 2) the sewage utilizes dissolved
oxygen as it decomposes, thereby causing the oyster physio-
logical stress, and 3) the sewage greatly increases the
bacterial content of the water. This increase does not
necessarily affect the development of an oyster bar, but
it does af f ect the utilization of the bar by commercial
fisheries. The numbers of Escherichia coli (an intestinal
bacteria of humans that passes out with the feces) found
in water flowing over a bar is an index of pollution
utilized by State and Federal Health officials. The
bacterial counts indicate whether or not the bar should be
closed.

Domestic sewage., per se, does not necessarily have to
be deleterious. Tenore and Dunston (1973) ran growth com-
parisons on the American oyster, q. virginica, the blue
mussel, Mytilus edulis, and the bay scallop, Aequipecten
irradians. Some of the animals were fed algae in a 20%
dilution of "f medium" (Guillard and Rytber., 1962), and
the others in a 10% dilution of secondary treated sewage
effluent. Both the organisms grown on the nutrient
medium and on the sewage effluent showed statistical
growth and no apparent harmful effects. Both media were
dominated by diatoms especially Stephanopryxis costata.
Tenore and Dunston (1973) were quick to point out that more
research is necessary before the use of sewage effluent
as an inexpensive source of nutrients for aquaculture is
wholeheartedly recommended. The reasons they gave are:
1) the experiment was too short (3 months) to determine
what the long-term effect of any pollutant, e.g., a harmful
trace metal or organic compound, might be on the organisms
and 2) juveniles were not used in the experiment, although.
many juveniles are more sensitive to pollutants than adults.
This sewage effluent utilized in the experlment was from an
efficient secondary treatment plant, and trace metal con-
centrations were low. Tenore and Dunston (1973) suggested

Appendix 15
288

the use of chemical analyses and bioassay test 's-to determine
the suitability of a particular effluent before it is usect
in aquaculture.

Another waste source is industrial waste. Galtsoff,
Chipman, Engle and Calderwood (1947) researched the effects
of pulp mill waste on oysters in the York River, Virginia.
These investigators were able to demonstrate that the
morphological and physiological characteristics of the
oysters of the upper York River are closely correlated to
the effluent of the pulp mill. These oysters, in a fairly
emaciated condition, do not accumulate glycogen and have
an abnormal shell condition as a result of a disturbance
of calcium metabolism. They were able to recover when
removed to cleaner waters. The poor productivity of the
area could not be blamed on the oysters' condition because
the available food sources of the area were equivalent to
or surpassed the availability of similar areas. Galtsoff
et al. (1947) conducted laboratory experiments with the
pulp mill effluent. He observed that it had a general
depressive effect on the physiology of the oyster. It
reduced the time the shell was open, thereby decreasing
feeding time; affected the efficiency of the ciliated
epithelium of the gills; and reduced the rate of pumping
by the gills. The actual toxic substances in the pulp mill
liquor could not be determined at the time of the experi-
ment because there was not a chemical test available for
the detection and determination of these substances.

The type of study conducted by Galtsoff et al. (1947)
needs to be conducted on several "Problem" ar@Ta`s of the Bay.
It was detailed and included the experiences and observa-
tions of several scientists working in collaboration to
solve a specific problem.

On 30 June 1965, there was an industry-wide conversion
by detergent manufacturers to a biodegradable linear alkylate
sulfonate type of detergent known under the acronym LAS.
Calabrese and Davis (1967) conducted experiments on the ef-
fect of this soft detergent on oyster eggs and larvae.
Their observations revealed that oyster eggs have a low tol-
erance of active LAS. Only 51 to 64% of the eggs developed
in concentrations of 0.05 and 0.10 mg/1 and even then., many
of the eggs were of abnormal s-ize and/or shape. At concen-
trations of 0.'25 mg/1 none of the eggs developed. Calabrese
and Davis compared their study to Hiduls (1965) results
which revealed that the old detergent base of alkyl benzene
sulfonate (ABS), in concentration as high as 0.50 mg/1
affected only 53% of the oyster eggs, allowing the rest to
develop normally. From the evidence it appeared that active
LAS is more toxic than active ABS.

Appendix 15
289

Larvae have a higher tolerance of LAS, but this tol-
erance decreases significantly between concentrations of
0.50 mg/l and 1.00 mg/l. Between concentrations of 0.25
mg/l and 0.50 mg/l of active LAS, development of the larvae
was Interrupted. At 1.00 mg/l, all the larvae died. Con-
centrations of treated LAS that reached 200 mg/l apparently
did not hinder normal growth of the oyster. It is therefore
assumed by Calabrese and Davis that LAS loses its toxicity
when passed through a sewage treatment plant and that if
there is any residual toxicity, it is masked by the toxicity
of the effluent itself.

A source of contamination that is rapidly becoming in-
creasingly important is pesticide pollution. Scientists
are still not able to fully define the problem or to eval-
uate the long-range effect on man and the coastal environ-
ment (Butler, 1964). They do know that they have caused
fish kills and other wildlife mortalities. However, this
grim picture does not present the benefits o,f pesticides.
The destructive and beneficial aspects of pesticides can
be illustrated in the following examples. Cottam and
Higgins (1946) reported that DDT is harmful to fish, amphi-
bians, crustaceans, birds and insects. Loosanoff (1947)
reported that if a cultch of oysters is sprayed with a
DDT suspension, the cultch's value is enhanced for catching
spat because fouling organisms are inhibited by DDT.
Several experim6nts with pesticides and herbicides have
been conducted on the Chesapeake Bay; both the beneficial
and detrimental observations will be presented.

Castagna, Chanley, Wass and Whitcomb'(1966) reported
the effects of Polystream and Sevin upon an oyster bed near
'Hog Island Bay, Wachapreague, Virginia. The purpose was to
see if Polystream and Sevin could be used as a drill control.
Results demonstrated only limited mortality, but there were
adverse effects noted on several macroinvertebrates. There
was a heavy mortality of polychaetes, amphipods, mantis
shrimp (Squilla empusa), sand shrimp (Crangon septemspinosa)
mud shrimp ('Upogebia afrinia and short razor clams (Tagelus
divisus) within three days of treatment. Many blue crabs
and mud crabs showed abnormal coordination of muscles, and
a few died. Of the drills, no moralities were noted, although
about 50% did not firmly attach to the substrate. Another
2% had swollen foot tissue and 10-15% were unable to retract
their foot quickly when stimulated.

The effects of Polystream and another pesticide called
Drillex were studied by Shaw and Griffith (1967). Their
observations were similar to those of Haven et al...In the
Tred Avon River, it was.observed that at the 5%-significance
level, more spat settled on the Polystream-treated shells

Appendix 15
290

than on the controls. Treatment with Drillex. did not
result in significant differences. However, in both
the Tred Avon River and Broad Creek, the -barnacle
Balanus improvisus set two and one-half to three times
more heavily on chemically treated shells than on un-
treated shells. The conclusions drawn from their report
are: 1) neither pesticide repelled the principal fouling
organisms of Chincoteague or Chesapeake Bay, 2) shell
growth of oysters was neither improved nor hindered by the
pesticides and 3) the treatments did not protect spat
from drill predation.

A set of experiments by Shaw and Griffith (1967)
involved dipping shells in Polystream and then adding
sand mixed with Drillex. The sediment containing treated
sand resulted in death of the shrimps Crangon and Palae-
monetes, the mud crabs and polychaetes. Boxes (empty
oyster shells) were observed immediately after application
of the treated sand, but fatalities ceased after two weeks.
After all the negative statements made above, it must be
noted that on rocks in Chincoteague Bay treated with
Drillex- treated sand and Polystream shells, over seven
times more spat settled than on plots with only Polystream-
treated shells. Because of significant differences between
chemically treated and untreated plots, further investigations
need to be conducted.

Earlier, effects of DDT were glossed over. Brodtmann
(1970) attempted to isolate the entry site and uptake me-
chanism of DDT. His data showed that uptake is apparently
caused by diffusion and that the primary entry site is the
gills. The gut may also be an entry site, but it is of
secondary importance. As with many of the heavy metals,
the oyster is able to accumulate DDT, but Brodtmann found
that there is a rapid rate of elimination of pesticides
when placed in uncontaminated water. Butler (1964) re-
ported essentially the same results as far as accumulation
and elimination is concerned. Butler (1964) observed that
under experimental conditions, if DDT concentration in-
creased from 1.0 ppb to 1.0 ppm, oyster growth decreased
20 to 90%. Butler (1964) also reported that DDT is stored
in the eggs of oysters. He was un -able to continue experi-
ments at that time on the development of contaminated
eggs and sperm, but he did report that Davis (1961) ob-
served 100% mortality in the oyster larval culture within
six days.

Rawls (1965) conducted experiments on the toxicity
of some estuarine animals to herbicides. The.herbicides
were to be utilized to control the Eurasian milfoil
Myriophyllum. spicAtUm L. The usual practice is to apply
herbicides during its most vulnerable period, just before

Appendix 15
291

flowering. This period is from mid May to mid June, after
the water warms to about 18 C. Rawls (1965) recommendation
was that 2,4 - DBE (2, 4 D butoxyethanol ester) or IOE
(Iso octyl ester) be utilized at rates of 20 to 30 lb acid
equivalent/acre in areas subject to tidal flushing. The
reason for advocating use in an area of total flushing is
that in one test, Rawls noted that the dead milfoil sank
to the bottom and smothered the oysters while it decomposed.
If a tidal current had carried it off 'however, this would
not have happened. 'Rawls (1965) pointed out that he does
not advocate control of aquatic vegetation by chemical
application. He feels that a bio-control 'developed through
,research would be more advantageous. Rawls (1965) paper
should be read closely by all water manager, not only
to understand the results of his own experiments, but to
glean the results he summarizes for other experiments on
studies of juvenile and/or eggs and the effects of herbi-
cides on them.

Lowe, Wilson, Rick and Wilson (1971) conducted experi-
ments on the insecticides DDT, toxaphene and parathion.
Two experiments were conducted. In the first experiment,
the oysters were exposed to all three pesticides simul-
taneously. Each pesticide was in a concentration of
about 1.0 ppb, making a total pesticide quantity of 3.0
ppb. The results revealed that there was a statistical
difference in body weight between the experimental oys-
ters and the controls. The controls outweighed the ex-
perimental by an average of 2.8 g. The organophosphate
parathion did not accumulate in the tissue, but DDT
and toxaphene did. Histopathological studies revealed
that there was a pathological response in the kidney
visceral ganglion, tissues beneath the gut, possibly
the gills and frequently the digestive tubes. After
36 weeks, the experimental oysters were infected by
a mycebial fungus which caused lysis of the mantle,
gut, gonads, gills, visceral ganglion and kidney tu-
bules. Intense inflammation and leucocytic infiltration
also was observed. The control oysters remained normal.

The second experiment conducted by Lowe, Wilson, Rick,
and Wilson (1971) consisted of raising the oysters in
separate containers, each containing 1.0 ppb of either
DDT or parathion or toxaphene. After twelve weeks, the
mean weight of the control oysters was consistently higher,
but there were no statistical-differences. Again DDT and
toxaphene were accumulated in the body tissues. Histopatho-
logical studies after 12 weeks did not show significant
observable effects, but after 36 weeks, there was a sug-
gestion of harm by parathion and toxaphene. Long-term
experiments need to be run to obtain more conclusive
evidence. The authors were not sure whether the

ADpendix 15
292

difference in effects was a result of total pesticidal
exposure or a synergistic effect of the three or both.

It is well known that oysters and many other marine
invertebrates are capable of accumulating various heavy
metals, such as zinc, copper, iron, manganese, lead
and arsenic, even when the concentrations in the wa-
ter are low. This accumulation can become a health
problem. Galtsoff (1964) reported that Hunter and
Harrison (1928) demonstrated that oysters from coastal
areas of Connecticut, New York, and New Jersey contained
traces of lead and arsenic. In the Chesapeake Bay,
Roosenberg (1969) observed an apparent relationship
between copper uptake in oysters and power plant op-
eration. The copper probably came from the condensor
tube in the plant, but Roosenberg (1969) stated that
the rate of accumulation is probably affected by mul-
tiple factors such as temperature, time of exposure
and physiological activity. It must be pointed out
that oysters had been observed to take copper before
the plant began to operate, but the addition of copper
plus the changes associated with the plant and the en-
vironment caused an increase in accumulation. Additional
work will have to be conducted to determine the mechan-
isms that stimulated copper accumulation. Copper af-
fects the oyster economic value because Of the greening
effect and the bitter taste. In extreme cases, the
toxic effect will leave the oysters totally unmarketable.

So far, man-made types of pollutants have been
discussed. Nature can cause considerable damage herself.
The tropical storm AGNES was responsible for damage still
felt by the oystermen in the summer and fall of 1974.
The fresh water associated with the storm disrupted the
set for the year 1972 even though the more mature oysters
survived. Since it takes two to three years for a young
oyster to reach the three-inch limit necessary for market-
ing, it is understandable why oyster production is down.
On the positive side, officials of Maryland and Virginia
have reported a healthy set which can be taken as a good
sign for future harvests (Richards, 1974).

MISCELIANEOUS COMMUNITIES

The benthic organisms Mya, Macoma and Gemma occupy the
mesohaline,region. They are dominant organisms controlling
energy flow to some extent and represent benthic organisms
of different substrates in the Bay, 'Mya: arenaria is of
economic importance. Around 1951, Maryland began to supply
the market with softshell clams when New England product-
ion declined primarily because of green crab predation

Appendix 15
293

(Pfitzenmeyer, 1962). Also, Ward, Rosen, and Tatro
(1966) showed that Mya might be used as a source of
glycogen. Oysters presently are used for this purpose,
but due to declining numbers and rising costs; Mya
could be utilized as a replacement.

Mya, Macoma and Gemma live in sand or mud. To a
casual observer a sand or mud flat appears barren, but
when covered by overlying water the bivalves extend their
siphons; horseshoe crabs, rays and flounders dig in
substrate for food; and large polychaete worms such as
Arenicola excrete castings forming fecal mounds. A flat
also contains a tremendous number of smaller organisms.
"Each gram of substrate may contain 500,000 bacteria,
thousands df diatoms and other algae, nematodes, copepods.,
ostracods, amphipods., etc.." (Pearse, Humm, and Wharton,
1942). Intertidal flats are not composed of a uniform
distribution of organisms, but rather exhibit discontinu-
ities. "The reasons for the irregularities are not.apparent,
but usually are associated with such factors as type and
stability of substrate, strength of current, wave action
and salinity" (Gray, 1974).

So far salinity zones in relationship to the organism
involved have been discussed. Every zone reflects the
plankton community, made up of both zooplankton and phyto-
plankton. Plankton forms the basic step in the estuarine
food web (,review Figure 15-15,). Phytoplankton fixes energy
of the sun for utilization as an energy source in the
upper levels of an estuary. Zooplankton are the primary
and secondary consumers on which still larger organisms
can feed. A great deal of information on Chesapeake Bay
plankton communities is lacking, but a few generalities
are known. Smayda (1973) reported the results of Cowles'
(1930) investigations:

1. "A winter-spring diatom bloom and a fall
maximum are interspersed by a summer minimum."

2. I'Dinoflagellates predominant in the summer,
and diatoms at other seasons."

3. "Phytoplankton pulses tend to be associated
with lower surface salinities" (Note: it is impossible
to state to what extent this reflects higher nutrient
levels through runoff, or is due to reduced mixin.g.
of the water column caused by the halocline or neither)."

Appendix 15
2 94

4. "There is inconclusive evidence whether diatom
growth is stimulated in the vicinity of river mouths."

Cowles (1930) found that Skeletonema costatum, Cerataulina
pelagica, Rhizosolenia fragilissima and R. stolterfothii
are the dominant winter diatoms in Chesapeake Bay.
Ceratium furca and Prorocentrum micans are the dominant
dinoflagellates. Whaley and Tayl-o-r-Tl-968) agreed with
Cowles findings in almost every respect except they found.
Asterionella japonica instead of Rhizosolenia stolterfothii
in their collections and were unable to demonstrate phyto-
plankton stimulation through river discharge.
7j@
Generalities about zooplankton communities in Chesapeake
Bay are scarce. It generally appears that copepods are the
dominant organisms in the water column. Two species, in
particular, are important. They are Acartia clausii,
dominant in the winter, and A. tonsa, dominant in ti@e
spring (Smayda, 1973). The substitution that occurs
between the two appears to be caused by salinity and
temperature changes. Plankton in general are difficult
to study because little is known about their life cycles,
and because they are subject to water currents as a mode
of transportation.

Fish are also difficult to study because of their
movement throughout an estuary, both by swimming and by
being transported by water currents. The Chesapeake Bay
is well known as a nursery ground for many sport and
commercial fish. Dovel (1970) considered fish as belonging
to three major groups depending on the salinity zone in
which they spawn: freshwater spawners, estuarine spawners
and marine spawners. Table 15-17 illustrates the fish involved
in each zone. Although he applied this division only to
the upper Bay, it also applies to many Chesapeake tributaries.

White and yellow perch, several species of herring
and the striped bass are freshwater spawners. (Note:
Dovel (1970) found these fish in salinity concentrations
up to 13 Ppt.) Striped bass spawn in the Nanticoke,
Choptank, Potomac, Patuxent, Rappahannock, York and James
Rivers (Saila and Pratt, 1973). Dovel (1970) concluded
that juveniles move into the higher salinities, utilizing
the plankton available there as a food source. In fresh-
water they do not appear to require nutrients in the imme-
diate environment because they posses yolk sacs.

Appendix 15
295

TABLE 15-17
COMMON FISHES OF UPPER CHESAPEAKE BAY
BY SALINITY ZONE (Dovel, 1970)

Common Name Scientific Name

FRESHWATER SPAWNERS

Blueback herring. Alosa aestivalis
Alewife Alosa pseddoharengus
American shad Alosa sapidissima
Silvery minnow Hybognathus nuchalis
White catfish Ictalurus catus
Channel catfish Ictalurus Dunctatus
White perch Morone americana
Striped bass Morone saxatilis
Warmouth Chaenobryttus Rulosus
Pumpkinseed Lepomis Aibbosus
Bluegill Lepomis Macrochirus
Johnny darter Etheostoma nigrum
Yellow perch Perca flavescens

ESTUARINE SPAWNERS

Bay anchovy Anchoa mitchilli
Atlantic needlefish Strongylura marina
Halfbeak Hyporhamphus unifasciatus
Northern pipefish Syngnathus fuscus
Naked goby Gobiosoma bosci
Striped blenny ChasmFd-es Fo-squianus
Rough silverside Membras martinica
Tidewater silverside Menidia beryllina
Atlantic silverside MeniTi-a menidia
Winter flounder Pseudopleuronectes americanus
Hogchoker Trinectes maculatus
Skilletfish (clingfish) Gobiesox strumosus
Oyster toadfish Opsan au

Appendix 15
296

TABLE 15-17 (cont'd)
C0101ON FISHES OF UPPER CHESAPEAKE BAY
BY SALINITY ZONE (Dovel, 1970)

Common Name Scientific Name

MARINE SPAWNERS

Atlantic menhaden Brevoortia tyrannus
American eel Anguill rostrata
Bal lyhoo Hemiramphus brasiliensis
Threespine stickleback Gasterosteus aculeatus
Silver perch Bairdiella chrysur
Weakfish Cynoscion regalis
Spot Leiostomus xanthurus
Southern kingfish Menticirrhus americanus
Atlanti-c croaker Micropogon undulatus
Seaboard goby Gobiosoma ginsburgi
Southern harvestfish Peprilus alepidotus

AnDendix 15
297

Estuarine spawners reproduce and mature in brackish
water areas. Some may stay in the same relative area where
they hatched whereas others, such as the bay anchovey and
hogehoker, move to the low salinity areas in the summer and
fall (Dovel, Mihursky and McEarlean, 1969).

Marine spawners, i.e., menhaden, American eel, spot,
weakfish and Atlantic croaker use the Bay as a nursery ground.
The larvae or juveniles of these species, expect for menhadbn,
appear in the Atlantic coast estuaries from late summer to
early winter., Juvenile menhaden appear in early spring.

Dovel (1970) listed several generalities of particular
application to the upper Bay. They are:

1. In the early spring the channel area displays
the greatest biological activity as a result of fish
moving downstream.

2. When the water temperature rises in the early
summer, the developing fish move to shallow areas
and feed. among the vegetation.

3. As summer progresses, the estuarine and
marine fish move upstream or inshore toward the
fresh-saltwater interface.

4. The deeper., warmer channels contain numerous
fish in the winger.

Figure l&-26 illustrates the movement of estuarine-dependent
fish larvae and juveniles to a low salinity nursery. Inter-
esting to note is that many juveniles appear to prefer the
low salinity nursery during the cold period (December through
March). It is felt by Clark (1967) and Dovel, et al. (1969)
that this exposure to cold might be necessary for the bio-
logical success of the species.

The last community that is under consideration
really comprises several communities, all of which fall
under the calssification "wetlands". Marcellus (1972)
defined wetlands as "all that land lying between and
contiguous to mean low water and an elevation above mean
low water equal to the factor 1.5 times the tide range ...
At the present time many governmental agencies, both state
and Federal, are concerned about wetlands'protection. They
are beginning to appreciate the practical value of maintaining

App endix 15
298

OCEAN BRACKISH A E FRESH WATER

LL<', -- - ---- F9

ESTUAR0,JE

MARINE

-717@
t
lt%t4
look

FIGURE 15-26: MOVEMENTS OF ESTUARINE-DEPENDENT FISH LARVAE AND JUVENILES TOWARD A
COMMON LOW SALINITY NURSERY AREA (Dovel, 1970)

Note: Ntunbers represent approximate salinity in parts per thousand.
4AT E

it v

the status quo.

Wetlands are-important for numerous reasons. Some
of these, as listed by Wass and Wright (1969) are:

1. "By converting inorganic compounds (nutrients)
and sunlight into plant tissue, they are of prime
importance as energy transfer mechanisms to consumer
organisms in the marsh and estuary."

2. "At the same time that nutrients are being
converted into vegetation, sediment and suspended
materials are being mechanically and chemically re-
moved from the water and deposited in the marsh."

a. "Were the nutrient not removed in
the marsh, they might stimulate blooms of
undesirable algae."

b. "Were the sediments not removed, some
of it would come to rest in navigation channels
and shellfish beds."

3. "Marsh vegetation slows flood waters and
helps stabilize channels, banks and water levels."

4. Yeast and bacteria transform the complex
molecules of cellulose "into other carbon compounds
digestable by animals and the changing of nitrogenous
wastes of animals into compounds available to plants
or lower animals".

5. 11 ... seeds of several brackish and freshwater
marsh plants and the leaves and rest of some submerged
aquatic plants are prime duck food."

Figures 15-27 and 28 vividly demonstrate the complexitv
of reactions that occur between the biotic and abiotic factors
of the wetland. Wass and Wright (1969) explained the use
of the plant material (detritus) to the rest of the estuary.
As plant material sinks, it is utilized by many juvenile
species because it is not yet,fine enough for suspension
feeders. That material not used by the juvenile forms is
mechanically worn down until it is small enough to be used
as a food source by small amphipods (e.g., Ampelisca abdita)
and opposum, shrimp. As the detritus moves out into the
channels and downstream, bivalves utilize this material.

Appendix 15
300

TOE
gl xxpuaddV

(696T .';q2TaM puv ssvm) xavflisa cinaciumEsux v xi
SlOHdaH.'IVOIS,&Hcl CKV DIIOIq dO SNOIIDVUalNI :LZ-s;T aaaDia

SNoi.LOV.U3lNl kHvn.LS3-HthiVW

PC
OSION
co
lll@ LAND ER
50
SQo
SrR.

A.
14,
110

>
v

. \ - xx@
he-\ I " I % 1.
A'
iR

@.l
Ilk,

wo/
Pal
ly
3&nj

164 T.0c

fhosep lk" VA"Se, #hGw M4*&N, Q.a.4 Tq q

:D. 094C.4 4-94- T,or-vrco M..4.0,M
id 01A."ftw I.. V.-n4 Fildip
fd C;:;@ Y..M& P" -Tft
(D
CA) :3
0

orm :@4qcz.

me.

afteom
SLIA Cm*o

beq.
Sir "#1 4111

RIW"

JI.A. a

o'd[wo-Im"

FACA
MAY
..Ko
%*A"
'1/
flit
ima I -U

LOW MAAO*, L.W7.0c m-#, Low r..

FIGURE 15-28: FEEDING INTERRELATIONSHIPS OF ANIMALS IN THE
LOW AND HIGH SALT MARSH (Shuster, 1966)

Dr. Marvin Wass prepared a detailed classification scheme
for the wetlands of Chesapeake Bay in Attachment 15-B.
In Attachment 15-C, Dr. Donald Boesch has listed the
dominant organisms of the polyhaline, mesohaline, tidal
freshwater, and oligohaline zones.

Appendix 15
303

LITERATURE CITED

Addy, C. E. and David A. Aylward. 1944. Status 'of eelgrass
in Massachusetts during 1943. J. Wildl. 8(4):269-275.

Aleem, A. A. and G. Petit. 1952. Charact6ristiques et
dvolution de la v6gdtation d1un etang des Pyren6es
Orientales: Comp. Rend. Acad. Sci., Paris. 235:632-634.

Allee, W.C. 1923. Studies in marine ecology: I. The
distribution of common littoral invertebrates of the Woods
Hole Region. Bio. Bull. 44(4):167-191.

1934. Concerning the organizati on of marine coastal
communities. Ecol. Monogr. 4(4):541-554.

Andrews, E. A. 1915. Distribution of Folliculina in 1914.
Bio. Bull. 29:373-380.

Andrews, J. D. 1965. Infection experiment in nature with
DermocXstidium marium in Chesapeake Bay. Ches. Sci.
b:bO-b7.
. 1966. Oyster mortality studies in Virginia. V.
Epizootiology of MSX, a protistan pathogen of oysters.
Ecology. 47:19-31.

Andrews, J. D.3 D. Haven and D. B. Quayle. 1959. Fresh-water
kill of oysters (Crassostrea virizinica) in James River,
1958. Proc. Nat. Shellfish Assjc-. 49:29-49.

Andrews, J. D. and J. L. Wood. 1967. Oyster mortality studies
in Virginia. VI. History and distribution of Minchinia
nelsoni, a pathogen of oysters, in Virginia. Ches. Sci.

Arasaki, M. 1950. The ecology of Amane (Zostera marina) and
Koamano (Zostera nana). Bull. Jap. Soc. Sci. Fisff_.
15(10):567-572.

Armiger, L. C. 1964. An occurrence of Labyrinthula in
New Zealand Zostera. New Zealand J. Bot. 2(l):3-9.

Atkins, W. R. G. 1938. The disappearance of Zostera marina.
J. Mar. Biol. Assoc. U. K. 23(l):207-21U. -

1947. Disappearance of Zostera marina. Nature (London)
159(4040):477.

Ai3Dendix 15
304

Azuma, M. and T. Huruda. 1968. Ecological studies on the
significance of Zostera region for the biological pro-
duction of fishes. (1) On the seasonal variation of
fauna in the Zostera region in the Seto Inland Sea.
Progress Report of Fishery Ground Improvement Project.
1967. 29 pp. Okayama Pref. Fish. Exp. Sta. (In Japanese).

Bader., R. G. 1954. The role of organic matter in determining
the distribution of pelecypods in marine sediments. J.
Mar. Res. 13:32-47.

1962. Some experimental studies with organic com-
pounds and minerals. In N. Marshall (ed.), Symposium on
the environmental chemistry of marine sediments, p. 42-57.
Occ. Publ. no. 1. Narragansett Mar. Lab., Univ. R. I.,
Kingston, R. I.

Beaven, G. F. 1946. Effect of Susquehanna River flow on
Chesapeake Bay salinities and history of past oyster
mortalities an upper Bay bars. Ches. Biol. Lab. Contr.
68:1-11.

1947. Observations of fouling of shells in Chesapeake
area. Conv. Add., Natl. Shellfish. Assoc. 1947:11-15.

Biebl, R. and C. P. McRoy. 1971. Plasmatic resistance and
rate of respiration and photosynthesis of Zostera marina
at different salinities and temperatures. Mar. Biol.
(Berlin). 8(1):48-56.

Blegvad, H. 1935. An epidemic disease on the eelgrass
(Zostera marina L.). Rept. Danish Biol. Sta. 39:3-8.
Blois, J. C.3 J. M. Francaz, M. Gaudichon and L. LeBris. 1961.
Observations sur les herbiers A Zoster-_@s de la R6gion de
Roscoff. Cah. Biol. Mar. 2:223-262.

Boesch, D. F. 1971. A distribution and structure of benthic
communities in a gradient estuary. Ph. D. Dissertation.
.Fac. Sch. Mar.-Sci. Coll. William and Mary. 120 pp.

Boysen-Je"nsen, P. 1914. Studies concerning the organic
matter of the sea bottom. Rep. Danish Biol. Sta.
2:1-39.

Brett, C..E. 1963. Relationships between marine invertebrate
infauna distribution and sediment type distribution in
Bogue Sound, Nor'th Carolina. Ph. D. Dissertation. Univ.
N. C., Chapel Hill., N. C.

Appendix 15-
305

Brodtmann, N. V. 1970. Studies on the assimilation of 1.1.1-
Trichloro - 2,2 - bis (p-chlorophenyl) ethane (DDT) by
Crassostrea virginica Gmelin. Bull. Environ. Contamin.
Toxicol. 3:455-462.

Broekema, M. M. M. 1941. Seasonal movements and 'osmotic
behaviour of the shrimp Crangon cranron L. Archiv.
Neederland de Zool. b(l):1-11b.

Broekhuysen, G. J. 1935. The extremes in percentages of
dissolved oxygen to which the fauna of a Zostera field
in the tidal zone at Nieuwediep can be exposed. Archiv.
Neederland de Zool. 1:339-346.

Bullock,, T. H. 1955. Compensation for temperature in the
metabolism and activity of poikilotherms. Biol. Rev.
30:311-342.

Bumpus, D. F., R. E. Lynde and D. M. Shaw. 1973. Physical
oceanography, p. 1-1 - 1-72. In: Saila (Prog. Coord.),
Coastal and Offshore EnvironmeFTal Inventory. Cape
Hatteras to Nantucket Shoals. Mar. Exp. Sta. Grad.
Sch. Oceanogr. Mar. Pub. Ser. No. 2. Univ. R. I.,
Kingston, R. I.

Butcher, R. W. 1934. Zostera. Report on the present con-
dition of eelgrass on the coast of England, based on a
survey during August to October, 1933. Cons. Perm.
Internat. Explor. Mer. Jour. Conseil. g(l):49-65.

Bulter, P. A. 1949. Gametogenesis in the oyster under
conditions of depressed salinity. Bio. Bull. 96:263-269.

1964. The problem of pesticides in estuaries. Amer.
Fish. Soc., Spec. Publ. No. 3:110-115.

Calabrese, A. and H. C. Davis. 1967. Effects of soft detergents
on embryos and larvae of the American oyster (Crassostrea
virginica). Proc. Nat. Shellfish Assoc. 57:11-16

Cameron, A. T. and I. Mounce. 1922. Some physical and
chemical factors influencing the distribution of marine
flora and fauna in the Strait of Georgia and adjacent
waters. Contr. Canad. Biol., N. S. 1:39-72.

Carriker, M. R. 1951. Observations on the penetration of
tightly closing bivalves by Busycon and other predators.
Ecology. 32:73-83.

. 1957. Preliminary study of behavior of newly
hatched oyster drills. Urosalpinx cinerea (Say).
J. Elisha Mitchell Sel. Soc. 73:328-351.

-Appendix-15
306

1961. Interrelation of functional morphology,
behavior, and autecology in early stages of the bi-
valve Mercenaria mercenaria. J. Elisha Mitchell Sci.
Soc. 77:168-2T-l.

. 1967. Ecology of estuarine benthic invertebrates:
a perspective, p. 442-487. In Lauff (ed.), Estuaries.
AAAS Pub. 83. Washington, U7. C. 757 pp.

Caspers, H. 1957. Black Sea and Sea of Azov, p. 801-889.
In J. W. Hedgpeth (ed.), Treatise on marine ecology and
paleoecology. I. Ecology. Geol. Soc. Amer. Memoir 67.
1,269 pp.

Cerruti, A. 1941. Observazioni ed esperimenti sulle cause
di distruzione della larvae dlostrica nel Mar Piccolo
e nel Mar Grande di Taranto. Arch. di Oceanogr. Limnol.,
Roma. 1:165-201.

Cheng,-T. C. and R. W. Burton. 1965. Relationships between
Bucephalus sp. and Crassostrea virginica: Histopathology
and sites of infection. hes. Sci. 6:3-16.

Chestnut, A. F. 1974. Oyster Reefs, p. 171-203. In H. T.
Odum, B. J. Copeland and E. A. McMahan (eds.). 'Coastal
ecological systems of the United States. The Conservation
Foundation, Washington D. C.

Clark., George L. 1954. Elements of Ecology. John Wiley and
Sons, Inc. 534 pp.

Clark, J. 1967. Fish and man, conflict in the Atlantic
estuaries. Spec. Pub. No. 5, Amer. Litt. Soc.

Collier, A. W. 1970. Oceans and coastal waters as life-
supporting environments, p. 1-94. In 0. Kinne (ed.),
Marine Ecology, Vol. 1, Part 1. Wilii-y - Interscience,
John Wiley and Sons. N. Y. 681 pp.

Conover, J. T. 1958. Seasonal growth of benthic marine plants
as related to environmental factors in an estuary. Univ.
Texas. Inst. Mar. Sci. 5:96-147.

Cooper, L. H. N. and A. Milne. 1938. The ecology of the Tamar
Estuary. II. Underwater illumination. J. Marine Biol.
Assoc., U. K. 22:509-527.

Copeland, B. J. 1970. Estuarine classification and responses
to disturbances. Trans. Amer. Fish. Soc. No. 4:826-835.

Cottam, C. 1933. Disappearance of eelgrass along the
Atlantic Coast. Plant Dis. Rept. 17(6):46-53.

Appe-ndix-1-5
307

Cottam, C. and D. Munro. 1954. Status of eelgrass. J.
Wildl. Mgmt. 18:449-460

Cottam, C. and E. Higgins. 1946. DDT: its effects on fish
and wildlife. U. S. Fish and Wildl. Circular 11. 14 pp.

Cottam, Cand C. E. Addy. 1947. Present eelgrass condition
and problems on the Atlantic Coast of North America.
Trans. N.Amer. Wildlife Conf. 12:387-397.

Cowles, R. P. 1930. A biological study of the offshore
waters of Chesapeake Bay. Bull. Bur. Fish. 46:277-381.

Cronin, L. Eugene. 1967a. The condition of the Chesapeake
Bay. Trans. 32nd N. A. Wildl. and Natl. Res Conf.,
Washington D. C. P. 138-150.

. 1967. The role of man in estuarine processes., p.
667-689. In George H. Lauff (ed.), Estuaries. AAAS
Publ. no. T3-., Washington, D. C. 757 PP.

.. 1971. IV. Prevention and monitoring pollution
prevention. Proc. Roy. Soc. Lond., B. .177:439-450.

Cronin, L. E. and J. J. Mansuetti. 1970. The biology
of the estuary, p. 14-39. In A symposium on the
biological significance of @T-stuaries. Sponsored by
the Sport Fishing Inst. in cooperation with Sportsmen's
Clubs of Texas, Inc. and Nat. Wildl. Fed. 111 pp.

Davis, H. C. 1949. On food requirements of larvae of Ostrea
virginica. Anat. Rec. 108:620. (Abstr. 230)

.. 1961. Effects of some pesticides on eggs and larvae
of oysters (Crassostrea virginica).and clams (Venus
mercenaria). Co . Fish Rev. 23:8-23.

Day, J. H. 1951. The ecology of South African estuaries.
Part I. A review of estuarine conditions in general.
Trans. Roy. Soc. S. Africa. 33:53-91.
'. 1967. The biology of Knysna estuary., South Africa,
P. 397-407. In G. H. Lauff (ed.), Estuaries. AAAS
Publ. no. 83--752 pp.

Day, J. H., N. A. H. Millard and A. D. Harrison. 1952.
The ecology of South African estuaries. Part III.
Knysna, a clear open estuary. Trans. Roy. Soc. S. Africa
33:367-413.

-App-en.dix- 15,
308

Dehnel', P. A. 1955. Rates of growth of gastropods as a
function of latitude. Physicol. Zool. 28:115-144.

Dexter, Ralph W. 1944. Ecological significance of the
disappearance of eelgrass at Cape Ann, Massachusetts.
J. Wildl. Mgmt. 8:173-176.

Dimitroff, V. T. 1926. Spirochaetes in Baltimore market
oysters. J. Bact. 13:135-177'.

Dodd, C. A. 1966. Epiphytic diatoms of Zostera marina
in Great South Bay. M. S. Thesis. Dept of Biol.
Adelphi University.

Dovel, W. L. 1960. Fish eggs and larvae, p. 42-49.
In Gross physical and biological effects of overboard
Tp-oil disposal in upper Chesapeake Bay. NRI Special
Report No. 3,,Contr. No. 397. NRI. Univ Md. '66 pp.

Dovel, W. L., J. A. Mihurskey and A. J. McErlean. 1969.
Life history aspects of the hogehoker, Trinectes
maculatus, in the Patuxent River Estuary, Maryland.
Ches. Sci. 10:119-140.

Duncan., F. M. 1933. Disappearance of Zostera marina.
Nature. 132:483.

Emery, K. 0. and R. E. Stevenson. 1957a. Estuaries and
lagoons. I. Physical and chemical characteristics,
p. 673-693. In J. Hedgpeth (ed.), Treatise on Marine
Ecology and P@Ueoecology, Vol. I Ecology. Geol. Soc.
.America. Memoir 67. 1296 pp.

. 1957b. Estuaries and lagoons. III. Sedimentation
in estuaries, tidal flats and marshes. In J-. Hedgpeth
(ed.)., Treatise on Marine Ecology and Pal-eoecology, Vol.
I. Ecology. Geol. Soc. America. Memoir 67. 1296 pp.

Evans, F. C. 19 56. Ecosystem as the basic unit in ecology,
p. 166-167. In Kormondy (ed.), Readings in ecology.
Prentice-Hall, Inc. Englewood Cliffs, N..J. 219 pp.

Fenchel,.T. 1973. Decomposition working group, p. 25-39.
In C. P. McRoy (Chairman), Seagrass Ecosystems: Recom-
mendations for Research Programs. Proceedings of the
International Seagrass Workshop. Leiden, The Netherlands
22 to 26 October 1973. 62 pp.

Fischer-Piette, E., Roger Heim et Robert Lami. 1932. Note
preliminare sur une maladie bact6rienne des Zost6res.
Compt. Rend. Acad. Sci. (Paris). 195:1420-1422.

Appendix 15
309

Frazier, J. M. 1972. Current status of knowledge concerning
the cause and biological effects of heavy metals in
Chesapeake Bay, p. S149-S153. In McErlean, Kerby and
Wass (eds.), Biota of the ChesaFeake Bay. Ches. Sci.
l3(SuPPl-):Sl-Sl97-

Frey, D. G. 1946. Oyster bars of the Potomac River. Fish
and Wildl. Ser. Spec. Sci. Rept. 32:1-93.

Flemer, D. A. 1972. Current status of knowledge concerning
the cause and biological effects of eutrophication in
Chesapeake Bay, p. S144-sl4q. In McElean, Kerby and
Wass (eds.), Biota of the ChesaFe-ake Bay. Ches. Sci.
13(SuPpl):Sl-Sl97.

Fuse, S. 1962. The animal community in the Zostera belt.
Physiol. and Ecol. Kyoto. 11:1-22. (In Japanese with
English summary.)

Galtsoff, P. S. 1960. Environmental requirements of oysters
in relation to pollution. In Biological problems in water
pollution. Trans. 1959 Semi-nar, Robert A. Taft San.
Eng. Ctr. Tech. Rep. w60-3:128-133.

1964. The American Oyster Crassostrea vir inica
Gmelin. U. S. Fish Wildl. Serv. Fish. Bull. 6-4:1-4dO.

Galtsoff,. P. S., W. A. Chipman,, J. B. Engle and H. N.
Calderwood. 1947. Ecological and physiological studies
of the effects of sulfate pulp mill wastes on oysters
in the York River., Virginia. U. S. Fish Wildl. Ser.
Fish. Bull. S1:59-189-

Gray, I. E. 1974. Worm and clam flats, p. 2o4-243. In
H. T. Odum, B. J. Copeland and E. A. McMahan (eds-.7,
Coastal Ecological Systems of the United States. The
Conservation Foundation, Washington, D. C.

Grim, R. E. 1953. Clay mineralogy. McGraw-Hill Co., N. Y.
Guillard, R. R. L. and J. H. Ryther. 1962. Studies on
marine planktonic diatoms. Can. J. Microbiol. 8:229-239.

Hartman, 0. 1945. The marine annelids of North Carolina.
Duke Univ. Mar. Station Bull. 2:1-151.

.Harvey, H. W. 1945. Recent advances in the chemistry and
biology of sea-water. Cambridge Univ. Press.

Appendix 15
310

Haskin, H. H. 1964. The distribution of oyster larvae,
P. 76-80. In Symposium on experimental marine ecology.
Occ. Publ. Fo-. 2. Narragansett Mar. Lab., Univ. R. 1.3
Kingston, R. I.

Hatanaka, M-and K. Iizuka. 1962. Studies on the fish
community of the Zostera area. I. The ecological order
for feeding in th@@__Yish group related to the dominant
species. Bull. Jap. Soc. Sci. Fish.. 28:5-16.

Haven, D., M. Castagna, P. Chanley, M. Wass and J. Whitcomb.
1966. Effects of the treatment of an oyster bed with
Polystream, and Sevin. Ches. Sci. 7:179-188.

Hedgpeth, J. W. 1953. An introduction to the zoogeography
of the northwestern Gulf of Mexico with reference to
the invertebrate fauna. Univ. Texas, Inst. Mar. Sci.
Pub. 3:107-224.

1957. Concepts of Marine Ecology, p. 29-52. In
Hedgpeth (ed.)j Treati8e-on Marine Ecology and Pai-eo-
ecology, Vol I. Ecology. Geol. Soc. Amer. Mem. 67.
1296 pp.

1957. Estuaries and lagoons.- II. Biological aspects,
P. 693-729. In Hedgpeth (ed.), Treatise on Marine Ecology
and Paleoecology, Vol. 1. Ecology. Geol. Soc. Amer.
Mem. 67. 1269 pp.

Hindu, H. 1965. Effects of synthetic surfactants on the
larvae of clams and oysters (Crassostrea virginica).
J. Water Poll. Contr. Fed. 37-7272-270.

Hunter,, J. F. 1912. Erosion and sedimentation in Chesapeake
Bay around the mouth of Choptank River. U. S. Geol.
Surv. Prof. Paper 90-B.

Hunter, A. C. and C. W. Harrison.. 1928. Bacteriology and
chemistry of oysters, with special reference to regula-
tory control of production, handling and shipment.
U. S. Dept. Agr. Tech. Bull. 64. 75 PP.

Ito, S. and T. Imai. 1955. Ecology of oyster bed. I. On
the decline of productivity due to repeated cultures.
Tohoku J. Agr. Res. 5:251-268.

Keller., M. and S. W. Harris. 1966. The growth of eelgrass
in relation to tidal depth. J. Wildl. Mgmt. 30:280-285.

Appendix 15
311

Kester, D. R. and R. A. Courant. 1973. Chemical oceanography
p. 2-1 - 2-36. In Salia (prog. coord.), Coastal and
offshore environFe-ntal inventory, Cape Hatteras to
Nantucket Shoals.- Mar. Exp. Sta. Sch. Oceanogr. Mar.
Publ. Ser. 2. Univ. R. I.J, Kingston, R. I.

Kikuchi., T. 1962. An ecological study on animal community
of Zostera belt, in Tomioka Bay, Amakusa, Kyushu.
II. Community composition (2) Decapod Crustaceans.
Records of Oceanographic works in Japan. Spec. No. 6.
P. 135-146.

. 1966. An ecological study on animal communities of
the Zostera marina belt in Tomioka Bay, Amakusa, Kyusha
Publ. Amakusa Mar. Biol. Lab. 1:1-106.

. 1968. Faunal list of the Zostera marina belt in
Tomioka Bay, Amakusa, Kyushu. Publ. Amakusa Mar. Biol.
Lab. 1:163-192.

Kinne, 0. 1964. The effects of temperature and salinity on
marine and brackish water animals. II. Salinity and
temperature -salinity combinations. Oceanogr. Mar.
Biol. Ann. Rev. 2:281-339.

1970. Temperature. General introduction, P. 321-346.
In 0. Kinne (ed.), Marine ecology, Vol I, Part.1. Wiley-
Yn-terscience, John Wiley and Sons, N. Y. 681 pp.

Kita, T. and E. Harada. 1962. Studies on the epiphytic
communities. I. The abundance and distribution of
microalgae and small animals on the Zostera blades.
Publ. Set. Mar. Biol. Lab. 10:245-257.

Kitamori., R.,.K. Nagata and S. Kobayashi. 1959. The ecological
study on "Moball (Zostera marina area). (II). Seasonal
changes. Bull. Naikai Reg. Fish. Res. Lab. 12:187-199.

Korringa, P. 1951. The shell of Ostrea edulis as a habitat.
Archives Neerlandaises de Zoologie, tome. 10:32-152.

1952. Recent advances in oyster biology. The Quart.
Rev. of Biol. 27:266-365.

Landers, W. S. and E. W. Rhodes. 1970. Some factors
influencing predation by the flatworm, Stylochus
ellipticus (Girard), on oysters. Ches Sci. 11:55-60.

Appendix 15
.312

Ledoyer, M. 1964a. La faune vagile des herbiers de Zostera
marina et le quelques biotopes d'algues infralit rales
dans la zone intertidale en Planche et comparaison avec
de milieux M6diterran6ens identifique. Rec. Trav. Sta.
Mar. Endoume. 34:227-24o.

1964b. Les migrations nyethemerales de la faune
vagile au sein des herbiers de Zostera marina de la zone
intertidale en Manche et comparYson avec les migrations
en Mediterrane6. Rec.Trav. Sta. Mar. Endoume. 34:241-
247.

Lewis, I. F. and W. R. Taylor. 1933. Notes from the Woods
Hole Laboratory. 1932. Rhodora. 35:147-154.

Loosanoff., V. L. 1946. Survival and mortality of frozen
oysters (Ostrea virginica). Anat. Rec. 96:199

1947. Effects of DDT upon setting growth and
survival of oysters. Fishing Gaz. 64:94-96.

1952. Behavior of oysters in water of low salinities.
Nat. Shellfish Assoc. Convention Addresses. 135-151.

1961. Effects of turbidity on some larval and adult
bivalves. Proc. Gulf and Carib. Fish Inst. 14th Ann.
Sess. Nov. 1961. p. 80-95.
Loosanoff, V. L. and F. D. Tommers. 1947. Effect of iow
pH upon the rate of water pumping of oysters, Ostrea
virginica. Anat. Rec. 99:668-669 (Abstr. 2457. -

Loosanoff., V. L. and J. B. Engle. 1943. Polydora in oysters
suspended in the water. Biol. Bull. 735:69-78.

1947. Effect of different concentrations of micro-
organisms on the feeding of oysters (0. virginica).
U. S. Fish Wildl. Serv. Fish. Bull. 42:31-57.

Loosanoff, V. L. and P. B. Smith. 1949. Some aspects of
behavior of oysters accustomed to different salinities.
Anat. Rec. 105:627 (Abstr. 309).

Lovelace, T. E., H. Tubiash an d R. R. Colwell. 1967.
Bacteriological studies of Crassostrea virginica in
Chesapeake Bay. Bacterial. roc. 1967:4b.

Lowe, J. I., P. D. Wilson., A. J. Rick and A. J. Wilson. 1971.
Chronic exposure of oysters to DDT, toxaphene and para-
thion. Proc. Nat. Shellfish. Assoc. 61:71-79.

Appendix 15
313

Lund, S. 1941. Tangforekomsterne i de danske Farvande og
Mulighederne for deres Udnyttelse. (The occurrence of
algae in the Danish waters and the possibilities for
their utilization.) Dansk. Tidsskr. Farm. 15(6).

Lund, J. W. G. 1969. Phytoplankton, P. 306-330. In
Eutrophication: Causes, Consequences, Coerrectlv-es.
Proceedings of a Symposium. NAS. Washington, D. C.
661 pp.

McCloskey, L. R. 1968. Community dynamics of the fauna
associated with Oculina.arbuscula Verrill (Coelenterata,
Scleractinia). Ph.D. Dissertation., Duke Univ. 187 PP.

McErlean, A. J. and C. J. Kerby. 1972. Biota of the Ches-
apeake Bay: Introduction, p. S4-S7. In McErlean,
Kerby and Wass (eds.). Biota of the Ch@T_sapeake Bay.
Ches. Sci. l3(SuPPl-):Sl-Sl97-

McHugh, J. L. 1966. Management of estuarine fisheries,
P. 133-154. In A symposium on estuarine fisheries.
Spec. Publ. N@E_- 3. Amer. Fish. Soc., Washington, D. C.

. 1967. Estuarine nekton, P. 581-620. In Lauff (ed.),
Estuaries. AAAS Publ. 83., Washington D.-C. 757 Pp.

.McKeough, M. 1968. The epiphytes and epizoans of-Zostera
marina in Great South Bay, L. I., N. Y. M. S. Thesis.
Dept. Biol., Adelphi University.

McNulty, J. K.p R. C. Work and H. B. Moore. 1962. Some
relationships between the infauna of the level bottom
and the sediment in South Florida. Bull. Mar. Sci.
Gulf Carribean. 12:322-332.

McRoy, C. P. 1966. The standing stock and ecology of
eelgrass Zostera marina. Izembek Lagoon, Alaska. M. S.
Thesis., Univ. Wa'gh-.,Seattle. 138 p.

1968. The distribution and biogeography of Zostera
marina (Eelgrass) in Alaska. Pac. Sci. 22:507Z-513.--

1969. Eelgrass under Arctic winter ice. Nature
224:818-819.

. 1970. Standing stocks and other features of eelgrass
(Zostera marina) populations on the coast of Alaska.
J. Fish. Re-s.Bd'. Can. 27:1811-1821.

McRoy, C. P. and R. J. Barsdate. 1970. Phosphate absorption
in eelgrass. Limnol. Oceanogr. 15:6-13.

Appendix 15
314

McRoy, C. P., R. J. Barsdate and M. Nebert. 1972. Phosphorus
cycling in eelgrass (Zostera marina L.) ecosystem. Limnol.
Oceanogr. 18:58-67. -

McRoy, C. P., J. J. Goering and B. Chaney. 1973. Nitrogen
fixation associated with seagrasses. Limnol. Oceanogr.
18:998-loO2.

MacGinitie, G. E. 1945. The size of the mesh openings in
mucous feeding nets of marine animals. Biol. Bull.
Woods Hole. 88:107-111.

MacKenzie., C. L. 1961. Growth and reproduction of the oyster
drill Eupleura caudata in the York River, Virginia.
Ecology. 42:317-33*8-

Manning, J. H. and H. H. Whaley. 1955. Distribution of
oyster larvae and spat in relation to some environmental
factors in a tidal estuary. Proc. Nat'. Shellfish.
Assoc. 45:56-65.

Marsh, G. A. 1970. A seasonal study of Zostera epibiota
in the York River., Virginia. Ph.D. Dissertation. Fac.
Schl. Mar. Sci. Coll. William and Mary. 156 pp.

Marshall, N. 1947. Abundance of bay scallops in the absence
of eelgrass. Ecology. 28:321-322.

Martin, A. C. and F. M. Uhler. 1939. Food of game ducks in
the United States and Canada. U. S. Dept. Agri. Tech.
Bull. 634. (Reprinted 1951 as U. S. Fish and Wildl. Serv.
Res. Rep. 30).

Martin, G..W. 1929. Three new dinoflagellates from New
Jersey. The Bot. Gaz. 87:556-558.

Massman,, W. H. 1971. The significance of an estuary on the
biology of aquatic organisms of the Middle Atlantic
region, p. 96-109. In A symposium on the biological
significance of estugries. Sponsored by the Sport
Fishing Inst. in cooperation with Sportman's Clubs of
Texas, Inc., and the Nat Wildl. Fed. 111 pp.

Mastrangelo, J. 1972. Map. The Washington Post, based on
data from the Chesapeake Research Consortium.

Menzies, R. J., J. S. Zaneveld and R. M. Pratt. 1967.
Transported turtle grass as a source of organic
enrichment of abyssal sediments off North Carolina.
Deep Sea Res. 14:111-112.

Appendix 15
315

Merrill, A. S.) K. 0. Emery and M. Rubin. 1965. Ancient
shells on the Atlantic continental shelf. Science.
147:398-4oo.

Merrill-, A. S. and K. J. Boss. 1966. Benthic ecology and
faunal change relating to oysters from a deep basin in
the lower Patuxent River., Maryland. Proc. Nat. Shellfish.
Assoc. 56:81-87.

Millard, N. A. H. and A. D. Harris on. 1952. The ecology of
South African estuaries. Part V. Richard's Bay. Trans.
Roy. Soc. S. Africa. 34:157-179.

Milne, L. J. and M. J. Milne. 1951. The eelgrass catastrophe.
Sci. Amer. 184:52-55.

YLobius, K. 1877. An oyster-bank is a biocoenose, or a
social community. p. 121-124. In Kormondy (ed.),
Readings in ecology. Prentice-Hall,, Inc. Englewood
CliffsA N. J. 219 pp.

Moffitt, J. 1941. Eelgrass depletion on the Pacific Coast
and its effect upon Black Brant. U. S. Dept. of Interior
Fish and Wildl. Serv. Wildl. Leaflet. 2o4:1-26.

Moore. H. B. 1955. Faecal pellets in relation to marine
deposits, P. 516-524. In P. D. Trask (ed.), Recent
Marine Sediments, a Symposium, Spec. Publ. 4, Soc.
Econ. Paleontologists Mineralogists.

1958. Marine ecology. John Wiley and Sons, New York.
493 pp.

Mounce, I and W. W. Diehl. 1934. Note on a new Ophiobolus
on eelgrass. Can. J. Res. 11:31.

1934. A new Ophiobolus on eelgrass. Can. J. Res.
11:242-246.

Munson, T.'O. and R. J. Huggett. 1972. Current status of
research on the biological effects of pesticides in
Chesapeake Bay, p. S154-S156. In McErlean, Kerby and
Wass (eds.), Biota of Chesapeakii-Bay. Ches. Sci.
13 (SuPpl.):Sl-Sl97.

Nagata, K. 1960. Preliminary notes on benthic gammaridean
Amphipoda from the Zostera region of Mihara Bay, Seto
Inland Sea, Japan. -F-ubl. Seto. Mar. Biol. Lab. 8:163-
182.

Appendix 15
316

Nagle, S. J. 1968. Distribution of the epibiota of
macroepibenthic plants. Contrib. Mar. Sci. Univ. Texas
13:105-144.

Needler, A. W. H. 1941. Oyster farming in Eastern Canada.
Bull. Fish. Res. Bd. Can. 60:1-83.

Nelson., T. C. 1926. Report of the department of biology.
Rep. Dept. Biol., N. J. Agr. Exp. Sta., 1925. p. 281-288.

1928. Pelagic dissoconchs of the common mussel,
Mytilus edulis, with observations on the behavior of the
larvae of allied genera. Biol. Bull. 55:18o-192.

-. 1947. Some contributions from the land in determining
conditions of life in the sea. Ecol Monogr. 17:337-346.

. 1952. Some observations on the migration and setting
of oyster larvae. Nat. Shellfish. Assoc. Convention
Address:99-104.

Nelson, B. W. 1962. Important aspects of estuarine sediment
chemistry for benthic ecology, p.27-41. In Marshall
(ed.), Symposium on the Environmental CheFfstry of
Marine Sediments. Occ. No. 1. Narragansett Mar. Lab.
Univ. R. I., Kingston, R. 1.

Nelson, J.. 1916. Report of the biologist. Rep. Biol. Dept.
N. J. Agr. Expt. Sta. 1915. p. 239-260.

Newcombe3 C. L.31 W. A. Horne and B. B. Shepard. 1939. Studies
on the physics and chemistry of estuarine waters in
Chesapeake Bay. J. Mar. Res. 2:87-116.

Odum, E. P.. 1959. Fundamentals of ecology. W. B. Sanders
Co., Philadelphia. 546pp.

1969. The strategy of ecosystem development.
Science. 164:262-270.

Odum, W. E. 1969. The structure of detritus based food
chains in a South Florida mangrove system. Ph. D.
Dissertation. Inst. Mar. Sci.J. Univ. Miami. Coral
Gables, Fla.

1970. Insidious alteration of the estuarine
environment.. Trans.Amer. Fish. Soc. No. 4:836-847.

Odum, H. T. and B. J. Copeland. 1974. A functional class-
ification of the coastal ecological systems, P. 5-84.
In H. T. Odum, B. J. Copeland and E. A. McMahan (eds.),
Coastal Ecological Systems of the Unit.ed States. The
Conservation Foundation, Washington, D. C.

Appendix 15
317

Olson, R. A.,$ H. F. Brust and W. L. Tressler. 1941. St'udies
of the effects of industrial pollution in the lower
Patapsco River area. CBL Pub. No.43. 40 pp.

Orth) R. J. 1971. Benthic infauna of eelgrass,Zostera
marin beds. M. S. Thesis. Dept. Mar. Sci.,Univ
Va. 79 Pp.

1973. Benthic infauna of eelgrass, Zostera marina,
-beds. Ches. Sci. 14:258-269.

Ostenfeld, C. H. 1908. On ecology and distribution of the
grass-wrack (Zostera marina) in Danish waters. Rep.
Danish Biol. a. No. 16. 62 pp.

1914. On the geographic distribution of seagras ses.
Royal Soc. Victoria Prov. 27(n. s.):179-190.

1918. Report on the Danish oceanographic expeditions
1908-1910 to the Mediterranean and adjacent seas. Biology,
Vol. 2.,,Seagrasses. 2:16.

Osterhout., W. J. V. 1917. Tolerance of fresh water by marine
plants and its relation to adaptation, Bot. Gaz. 63:
146-149.

Parker, R. H. 1955. Changes in the invertebrate fauna,
apparently attributable to salinity changes in the bays
of central Texas.@ J. Paleontol. 29:193-211.

Pearse, A. S. and G. Gunter. 1957. Salinity. Geol. Soc.
Am. Mem. 67:129-157.

Pearse, A. J., H. J. Humm and G. W. Warton. 1942. Ecology
of sand beaches at Beaufort. Ecol. Monogr. 12:135-190.

Percival, E. 1929. A report on the fauna of the estuaries
of the River Tamar and the River Lynher. J. Mar. Biol.
Assoc., U. K. 16:81-108.

Petersen, H. E. 1935. Preliminary report on the diease of
the eelgrass (Zostera marina L.). Rept. Danish Biol.
Sta. 4o:1-8. -

Pfitzenmeyer, H. T. 1962. Periods of spawning and setting
of the soft shell clam, M-ya arenari , at Solomons,
Maryland. Ches. Sci. 3:114-120.

Phillips, R. C. 1974. Temperate grass flats, p.244-299.
In H. T. Odum, B. J. Copeland and E. A. McMahan (eds.),
U-oastal ecological systems of the United States. The
Conservation Foundation, Washington, D. C.

Appendix 15
. 318

Phillips, R. C. and S. Grant. 1965. Environmental effect
on Phyllospadix scouleri Hooker and Zostera marina L.
leaves. (Abstr.) 16th Ann. AIBS Meet.

Pomeroy, L. R. 1960. Residence time of dissolved phosphates
in natural waters. Science. 131:1731-1732.

Pomeroy, L. R., E. E. Smith and C. M. Grant. 1965. The
exchange of phosphate between estuarine waters and sedi-
ments. Limnol. Oceanogr. 10:167-172.

Pomeroy, L. R., R. E. Johannes, E. P. Odum and B. Roffman.
1969. The phosphorus and zinc cycles and productivity
of a salt marsh, p. 412-419. In D. J. Nelson and F. C.
Evans (eds.), Symp. Radioecol. Proc. 2nd Nat. Symp.
Ann Arbor, Mich.

Pratt, S. D. 1973. Benthic fauna, P-5-1 - 5-70. In Saiia
(Prog. Coord.), Coastal and offshore environmeE-tal
inventory. Cape Hatteras to Nantucket Shoals. Mar.
Exp. Sta. Grad. Sch. Oceanogr. Mar. Publ. Series No. 2.
Univ. R. I.,Kingstop, R. I.

Pritchard, D. W. 1952. Salinity distribution and circulation
in the Chesapeake Bay estuarine system. J. Mar. Res.
ll(No. 2):106-123.

1955. Estuarine circulation patterns. Proc. Am.
Soc. Civil Engrs. 81:1-11.

. 1967. What is an estuary: physical viewpoint p.
3-8. In Lauff (ed.), Estuaries. AAAS Pub. No. 63.
Washini-ton, D. C. 757 PP.
Rawls,'C. K. 1965. Field tests of herbicide toxicity to
certain estuarine animals. Ches. Sci. 6:150-161.

Reid, G. K. -1961. Ecology of inland water and estuaries.
Reinhold Publ. Corp., N. Y. 375 PP.

Remane, A. and Carl Schlirper. 1971. Biology of Brackish
Water. Wiley Interscience Div. John Wiley and Sons,
Inc. N. Y. 372 pp.

Renn, C. E. 1934. Wasting diease of Zostera in American
waters. Nature. 134:416.

1936. The wasting diease of Zostera marina. Biol
Bull. 70:148-158.

Appendix 15

Richards., B. 1974. Oystermen in trouble. The Washington
Posti. 26 Sept. 01 pp.

Richardson., M. D. 1971. Benthic macroinvertebrate communities
as indicators of pollution in the Elizabeth River,
Hampton Roads, Virginia. M. A. Thesis. Fac. Sch. Mar.
Sci.,Coll. William and Mary. 104 pp.

Ricketts, E.'F. and J. Calvin. 1948. Between Pacific Tides.
Stanford Univ. Press. Stanford, Calif. 516 pp.

Rochford, D. J. 1951a. Hydrology of the estuarine environ-
ment. Proc. Indo. Pac. Fish. Coune. 1950. Sec. 3.
P. 157-168.

_. 1951b. Studies in Australian estuarine hydrology.
I. Introduction and comparative features. Austral.
J. Mar. Freshw. Res. 2:1-116.

Rosenberg, W. H. 1969. Greening and copper accumulation in
the American Oyster, Crassostrea virginica, in the
vicinity of a steam electric generating station. Ches.
Sci. 10:241-252.

Ryther, J. H. 1954. The ecology of phytoplankton blooms
in Moriches Bay and Great South Bay, Long Island,
New York. Biol. Bull. 106:198-209.

Saila, S. B. and S. D. Bratt. 1973. Fisheries, p. 8-1
8-138. In Saila (Prog. Coord.), Coastal and Offshore
Environmental Inventory. Cape Hatteras to Nantucket
Shoals. Mar. Exp. Sta. Grad. School Oceanogr. Mar. Pub.
Ser. No. 2.

Sanders, H. L. 1956. The biology of marine bottom communities.
X. In Oceanography of Long Island Sound 1952-1954.
Bull. Bingham Oceanogr. Coll. 15:345-414.

. 1958. Benthic studies in Buzzards Bay. I. Animal
sediment relationships. Limnol. Oceanogr. 3:245-358.

. 1960. Benthic studies in Buzzards Bay. III. The
structure of the soft-bottom community. Limnol.
Oceanogr- 5:138-153.

1968. Marine benthic diversity: A comparative study.
Amer. Nat. 102:234-282.

Sanders, H L., E. M. Goudsmit., E. L. Mills and G. E.
Hamps@n. 1962 * A study of the intertidal fauna of
Barnstable Harbor, Massachusetts. Limnol. Oceanogr.
7:63-79.

Appendix 15
320

Sando, H. 1964. Faunal list of the Zostera marina region
at Kugurizawa coastal waters. Aomori Bay. Bull. Mar.
Biol. Sta. Asamushi. 12:27-35.

Schubel, J. R. 1972. The physical and chemical conditions
of Chesapeake Bay: An evaluation. Spec.-Rep. 21.
CBI John Hopkins Univ., Baltimore, MD. 73 pp.

Scott, K. M. F., A. D. Harrison and W. Macnae. 1952. The
ecology of South African estuaries. Part II. The Klein
River estuary, Hermanus Cape. Trans. Roy. Soc. S.
Africa. 33:283-331.
J-
Segerstrale, S. G. 1957. Baltic Sea, P. 751-800. In
Hedgpeth (ed.), Treatise on marine ecology and Fa-leo-
ecology. Vol. I. Ecology. Geol. Soc. Amer. Memoir
67. 1269 pp.

Seitz, R. C. 1971. Drainage area statistics for the
Chesapeake Bay fresh water drainage basin. CBI Ref. No.
71-1. 'Johns Hopkins Univ., Baltimore, Md. 21 pp.

Setchell, W. A. 1922. Zostera marina and its relation to
temperature. Science. 56:575-577.

1. 1929. Morphological and phenological notes on
Zostera marina L. University of California Press.
Berkeley Calif. P-389-452.

Shannon, C. E. and W. Weaver. 1963. The mathematical
theory of communication. Univ. Ill. Press, Urbanna.
117 Pp.

Shaw, W. N. 1967. Seasonal fouling and oyster setting on
asbestos plates in Broad Creek, Talbot County, Maryland.
1963-65. Ches. Sci. 8:228-236.

Shaw, W. N. and G. T. Griffith. 1967. Effects of Polystream.
and Drillex on oyster setting in Chesapeake Bay and
Chincoteague Bay. Proc. Nat. Shellfish. Assoc. 57:17-23.

Shelford, V. E. and E. D. Towler. 1925. Animal communities
of the San Juan Channel and adjacent areas. Univ. Wash.
Puget Sound Biol. Sta. Pub. No. 5:33-73.

Sherk, J. A. 1972. Current status of the knowledge of the
biological effects of suspended and deposited sediments
in Chesapeake Bay, p. S137-S144. In McErlean, Kerby and
Wass (eds.), Biota of the Chesapea7-e Bay. Ches. Sci.
l3(SuPPl-):Sl-Sl97-

Appendix 15
321

Schuster, C. N. 1966. The nature of -a tidal marsh. The
Conservationist. 21:

Smayda, T. J. 1973. Phytoplankton, P. 3-1 - 3-100. In
Saila (Prog. Coord.), Coastal and offshore environmental
inventory. Cape hatteras to Nantucket Shoals. Mar.
Exp. Sta. Grad. School Oceanogr. Mar. Publ. Ser. No. 2.

Stauffer, R. C. 1937. Changes in the invertebrate community
at a lagoon after disappearance of the-eelgrass. Ecology.
18:427-431.

Steel., R. G. D. and J. H. Torrie. 1960. Principles and
procedures of statistics. McGraw-Hill Co., N.'Y.
481 pp.

Stephenson, W. 1951. Preliminary observations upon the
release of phosphate from estuarine mud. Proc. Indo-Pac.
Fish. Coune. 1950. Sec. 3. pp. 184-189.

Stone., R. B. 1963. A quantitative study of benthic fauna.
in lower Chesapeake Bay with emphasis on animal-sediment
relationships. M. A. Thesis. School of Mar. Sci.
Coll. of William and Mary. 40 pp.

Swartz, R. C. 1972. Biological criteria of environmental
change in the Chesapeake Bay, p. S17-S41. In McErlean
Kerby and Wass (eds.), Biota of the Chesapeake Bay.
Ches. Sci. 13(SuPP1.):Sl-Sl97.

Taylor, A. R. A. 1957. Studies of the development of
Zostera marina L. I. The embryo and seed. Can J. Bot.
35'@.77499.

. 1957. Studies of the development of Zostera marina
L. II. Germination and seedling development. Can.
J. Bot. 35:681-695.

Taylor, W. R. 1933. Epidemic among Zostera colonies.
. Rhodora. 35:186.

Tenore, K. R. and W. M. Dunstan. 1973., Growth comparison
of oysters, mussels and scallops cultivated on algae
grown with'artificial medium and treated sewage effluent.
Ches. Sci. 14:64-66. 41-

Thorson, G. 1950. Reproductive and larval ecology of marine
bottom invertebrates. Biol. Rev. 25:1-45.

Appendix 15
322

1957. Bottom communities (sublittoral or shallow
shelf), p. 4061-534. In Hedgpeth (ed.), Treatise on
marine ecology and pal-eoecology. I. Ecology. Geol.
a.
Soc. Amer. Memoir 67. 1296 pp.

Tully, J. P. 1949. Oceanography and prediction of pulpmill
pollution in Alberni Inlet. Bull. Fish. Res. Bd.
Canada 83. 169 pp.

Tutin.,, T. G. 1938. Autecology of Zostera marina in relation
to its wasting disease. New Phytologist. 37:50-71.

Vaughn, M. W. and A. W. Jones. 1964. Bacteriological
survey of an oyster bed. Ches. Sci. 5:167-171.

Ward, J., B. Rosen and M. C. Tatro. 1966. Extraction of
glycogen from soft shell clams (Mya arenaria).
Ches. Sci. 7:213-214.

Wass, M. L. 1967. Biological and physiological basis of
indicator organisms and communities. Section II.
Indicators of pollution, p. 271-283. In Olson and Burgess
(eds.), Pollution and marine ecology. Interscience
Publ. John Wiley and Sons, N. Y. 364 pp.

Wass, M. L. and T. D. Wright. 1969. Coastal wetlands of
Virginia. Interim Report of the Governor and General
Assembly. Spec. Rep. Appl. Mar. Sci. and Ocean Eng.
No. 10. VIMS, Gloucester Point, Va. 154 pp.

Webster, J. R. and R. Z. Medford. 1961. Flatworm distribution
and associated oyster mortality in Chesapeake Bay. Proc.
Nat. Shellfish. Assoc. 50:89-95. .

Well, H. W. 1961. The fauna of oyster beds with special
reference to the salinity factor. Ecol. Monog.
31:239-266.

Whaley, R. C. and W. R. Taylor. 1968. A plankton survey
of the Chesapeake Bay using a continuous underwater
sampling system. Tech. Rep. CBI. Ref. 68-4. Johns
Hopkins Univ., Baltimore, Md. 89 pp.

Williamson, F. S. L. 1972. Biology and the Chesapeake
Bay. J. Wash. Acad. sci. 62:88-102.

Wilson., D. P. 1949. The decline of Zostera marina L. at
Salcombe and its effects on the i-hore. J. Mar. Biol.
Assoc... U. K. 20:395-412.

Appendix 15
323

Wood 3E. J. F. 1953. Reducing substances in Zostera. Nature
172:916.

. 1959a. Some east Australian seagrass communities.
-Linneas Soc. New S. Wales Proc. 84:218-226.

1959b. Some aspects of the ecolo,r-,,, Lake Macquarie,
N. S. W. with regard to an alleged de,@,-etion of fish.
Cn.
Aust. J. Mar. Freshwater Res. 10:322-340.

Young, E. L. 111. 1943. Studies on Labyrinthula, the etiologic
agent of the wasting diease of eelgrass. Amer. J. Bot.
30:586-593.

Young, J. S. and C. I. Gibson. 1973. Effects of thermal
effluent on migrating menhaden. Mar. Poll. Bull.
4:94-95.

Zenkevich, L. A. 1957. Caspian and Aral Seas, p. 891-916
In Hedgpeth (ed.), Treatise on marine ecology and paleo-
ecology. I. Ecology. Geol. Soc. Amer., Memoir 67.
1296 pp.

Appendix 15
324

CHAPTER VII

WATER QUALITY STANDARDS AND CRITERIA

As concern about water pollution has grown, water.quality
standards have understandably developed as a consequence
of the desire to simplify and objectivize pollution con-
trol procedures. From the start, standards and water use
classifications have been controversial, often thought
to be too restrictive by those discharging wastes, or
oversimplified by those seeking to preserve or enhance
water quality. However, current trends are toward both
proliferation and formalization of standards affecting
water quality.

This chapter, prepared by Drs. Donald F. Boesch and
Marvin L. Wass, of the Virginia Institute of Marine Sci-
ence, and coordinated through the Chesapeake Research
Consortium (CRC), will review existing water quality
standards and criteria, especially as they relate to
Chesapeake Bay biota. In continuance of studies pre-
sented in the Existing Conditions Report, the CRC under-
took to: 1) identify all Federal and State standards,
criteria and guidelines concerning or affecting water
quality; 2) indicate which of these are most pertinent
to water quality in Chesapeake Bay; 3) evaluate the bio-
logical bases of these regulations and objectives with
particular emphasis on the biota occurring in the Bay;
4) indicate those areas where water quality may not
conform to the standards or guidelines; and 5) assess
the impact of compliance with these standards on Chesa-
peake Bay ecosystems.

The Existing Conditions Report presented summaries of
the water quality criteria existent or biing proposed at
the time of its release and identified those pertinent
to the Chesapeake Bay. This report updates that compen-
dium. For the indepth evaluation of these criteria and

Appendix 15
325

standards (goals 3, 4, and 5 above), the Consortium
planned to address eight specific water quality problems
identified as being of importance in Chesapeake Bay.
These together with a brief description of the reasons
for selection, are (order of listing of no particular
significance):

1) Nutrients (specifically nitrogen and phosphorus
compounds): even with the broad application of
secondary treatment of sewage, nutrient loading
will continue to be a problem as the area
population grows; nutrient loading is implicated
in algal blooms in tidal-freshwater Potomac and
James rivers and, may be a factor in the "red
tides" in higher salinities.

2) Dissolved oxygen: low DO phenomena occur
annually in deeper waters of the Bay (e.g.,
upper Bay and Rappahannock River) and the
feeling exists that they are increasing in
frequency, duration, and distribution; exten-
sive oxygen depletion of waters below 17 ft.
in the lower Potomac in summer; even though
direct organic loading via sewage and indus-
trial wastes should diminish, the secondary
effects of nutrient loading,may cause oxygen
depletion.

3) Temperature: effects of power plants have
generated much controversary; power plant
siting has thus become a serious problem.

4) Chlorine: residual chlorine has been respon-
sible for mortalities of plankton entrained
in power plant cooling waters and for fish
kills near sewage treatment plants (e.g.,
James River, summer 1973); and may become
an increasing problem because of new limita-
tions for coliform bacteria in sewage
effluents.

5) Fecal pathogens: high fecal coliform counts
have recently caused closure of extensive
shellfish grounds, particularly in Maryland
and there is widespread feeling that coliform
determinations are inadequate and/or inappro-
priate.

Appendix 15
326

6) Dredge spoil: local agencies increasingly
disfavor overboard disposal of "polluted"
spoil; availability of "land" disposal sites
is decreasing, although the material from
maintenance dredging requiring disposal is
probably increasing.

7) Heavy metals (particularly mercury, copper
lead, zinc, chromium and cadmium): con-
centration occurs in sediments and organ-
isms; association with sewage and industrial
effluents and dredge spoil.

8) Oil: increasing transport occurs in the Bay;
several refineries are planned; there is a
potential onshore impact of outer contin-
ental shelf oil development.

Because of the mid-contract reduction of funding, however,
the Consortium was able to complete analyses for only
two--chlorine and oil. It is unfortunate that the
other topics could not be covered similarly, but
fortunate that these two represent pollutants whose
potential importance in the Chesapeake Bay is just
becoming realized and thus has not been reviewed
before.

Nonetheless, there is an effort to point out, where
possible, the implications of new water quality cri-
teria and effluent standards for Chesapeake Bay environ-
mental quality problems in addition to those thoroughly
reviewed.

INTRODUCTION

Considerable misunderstanding exists concerning the
semantics of the various regulations and recommendations
4, related to water quality. The terms "standard" and
"criteria" have distinctly different and now rather
formal meanings as shown in Figure 15-29.(4)

Appendix 15
327

. CRITERIA for specific Recreational.and
Qualities and quantities, > Aesthetic Waters
based on scientific Public Water Supplies
determinations$ which uses in Fresh Waters
must be identified and Marine Waters
may-havo to be c6-ntrolled. Agricultural Waters
Industrial Water
Supplies
Identification
pathway

IDENTIFICATION
Analytical methods (The operation needed
(chemist, biologist, for detecting and
measuring charac-
engineer, recreational
specialists & others). teristics of water.)

MONITORING
Deployment of measuring (The chronological
instruments to provide and spatial sam-
criteria and information pling operations
for assessment and control needed.)

STANDARDS
Definition of acceptable
quality related to unique
W local situation involving
political, economic and
social factors and including
plans for implementation
and questions of water use
and management.

FIGURE 15-29: RELATIONSHIP OF WATER QUALITY CRITERIA AND STANDA.RDS
(NAS/NAE, 1973)

,kppendix 1.5
328

Standard applies to a definition, established by govern-
mental authority, of acceptable quality for an intended
use. As such it has official regulatory or quasi-
legal status. Standards reflect political, economic
and social, as well as scientific, factors and may
include plans for implementation and questions of water
use and management.

Criterion applies to a scientifically based recommenda-
tion of the limits of alteration which do not affect
the suitability of water quality for an intended use.
Criteria are taken into consideration and often form
the bases of standards. Neither "standard" nor "cri-
terion" are synonyms for such commonly used terms as
"objectives" and "goals." Objectives represent aims
or goals toward which to strive to achieve certain
desirable conditions. As such they are not rigid
regulations, but may in fact include certain standards
and schedules which may be enforced. An example is
the National Pollution Discharge Elimination System
(NPDES) which is discussed below. Despite the rather
precise definitions of the terms "standard" and
11criterion" to be found in such sources-as McKee and
Wolf(l), Federal Water Pollution Control Administration
tion(2), Warren(3), and National Academy of Sciences/
National Academy of Engineering(4), confusion is often
propagated by alternate uses of these terms or by the
introduction of new terms.

Standards and criteria are generally developed to apply
to particular water use classes. Thus, water use
classifications are made with the intention that all
waters within a certain class be maintained suitable
for a particular designated use. The proposed Environ-
mental Protection Agency water quality criteria apply
to five classes of usage: Recreation, Public Water
Supply, Freshwater Life and Wildlife, Marine Life and
Wildlife, and Agriculture. State water use classifi-
cations are generally based on suitability for public
water supplies, contact recreation, shellfish harvest-
ing, and propagation of trout.

Other terms are often used concerning regulations
and recommendations related to water quality, e.g.,
'Iguidelines", "requirements" and "limitations."
Of these, the meaning of "limitations" deserves
elaboration because its usage is becoming widespread
in the context of effluent limitations. These are
in reality effluent "standards" in that they set

Appendix 15
329

specific limits on the permissible characteristics of efflu-
ents which must be met in obtaining dischar ge permits. Thus,
although effluent limitations may not relate specifically to
the quality of natural water bodies, their effect on water
quality may be profound.

BACKGROUND
Early water quality criteria concerned tho suitability of
water for human consumption and evolved from simple physical
tes-'s of taste, odor or appearance to microbiological cri-
teria, once the germ theory of disease was recognized. But
it was not until this centurythat scientific advances were
broadly applied to the measurement of water quality and that
criteria were developed for uses other than public water
supplies.

Water quality criteria and standards have been extensively
promulgated by federal, state and interstate agencies since
the 1940's (see sour 'ces 1 and 3 for a full discussion of these
developments). Of particular significance was the impact
of the Federal Water Pollution Control Acts of 1948 and 1956
as amended by the Water Quality Act of 1965, which required
that the states adopt water quality standards applicable to
interstate waters and a plan of implementation and enforce-
ment of these standards. As a means of assisting the,states
in determining standards, the Federal Water Pollution Control
Administration published in 1968 the Report of the National
Technical Advisory Committee entitled "Water Quality Cri-
teria", often referred to as the "Green Bookil 1 containing
recommendations on criteria for various water uses.

By far the most sweeping legislation on water pollution
control ever passed is the Federal Pollution Control Act
of 1972 (P.L. 92-500). It extends ultimate jurisdiction
of all navigable waters to the Federal government and sets
a national goal of elimination of all discharges by 1985.
P.L. 92-500 requires the development by the states of water
quality standards which must be approved by the Administrator
of the Environmental Protection Agency, and requires that
effluent limitations for point source discharged be promul-
gated. The Act also requires that the Administrator develop
and publish water quality criteria accurately reflecting the
latest scientific knowledge on health and welfare V aquatic
organisms and communities and on the-concentTation and dis-
persal of pollutants. EPA has released proposed water qual-
ity criteria (5), to replace the "Green Book", which are
largely based on recommendations from the National Academies
of Science and Engineering (4). When the full implications
of.the Act are realized, it is apparent that these water
quality criteria will have impacts, unprecedented by their
predecessors, on the water quality standards developed by
the states.

Appendix 15
330

THE SCIENTIFIC BASES OF STANDARDS AND CRITERIA

T11c bases of scientific knowledge upon which water quality
criteria for Dublic., agricultural, and industrial water
supplies are based are far more auequate than those for
aquatic life. Also., in these cases our technology allows
some pretreat.ment of substandard quality. Determination
of acceptable water quality for the survival, reproduction
and rrowth of marine and freshwater organisms is far more
difficult than determining the water quality needs of other
uses.

V._,ater quality Cr4 teria for marine and freshwater life are
typically based on short-term laboratory bioassays in which
.there is a determination of the concentration of pollutant
which is lethal to half of the population of a test species
in a fixed period of time, often 96 hours (96 hour LC50).
The criterion is usually set lower (perhaps by one or two
orders of magnitude) than this lethal level by multiplication
by a more or less arbitrary "application factor". The appli-
cation factors are set with a consideration of the sublethal
effects which are known or predicted for the particular pol-
lutant and the propensity for accumulation and concentration
of the pollutant in the environment and in organisms.

Acute toxicity bioassays have been widely criticized on a
number of grounds. The most basic criticism is that tests
run on one or a few species cannot be expected to reflect
the response of the many species which constitute aquatic
communities. Often, exceptionally hardy species, such as
goldfish, flathead minnows or killifish, are used as the
test organisms because they are generally easily obtainable
and can be maintained in the laboratory with relative ease.
"Fragile" species which are difficult to keep in the labora-
tory, yet are more sensitive to toxicity, are not generally
used for practical reasons. Furthermore adult organisms are
most often used, whereas the juveniles and larvae are gener-
ally the more sensitive life stages. The existence within
species of physiological races with varying susceptibility
to toxicants further complicates the extrapolation of bio-
assay results.
Most bioassays are of short duration and the assessment of
chronic effects, perhaps as measured by the ability to com-
plete a life cycle, although highly desirable, remains often
prohibitively expensive. Acute and chronic bioassays of
lethal toxicity do not, of course, reveal the potential of
sublethal effects, such as those influencing migration and
ot'I'ler behavior patterns, susceptibility to disease and pred-
fp ators, reproduction, genetics, nutrition, or physiology.
Such sublethal effects are of increasing concern and their
assessment offers the biggest challenge to water pollution
biology.

Appendix 15
331

')OsPitc these serious sh0r-c0mings, practical considerations
often leave little choice but to develop criteria based on
acuto lethal bioassays and conservative application factors.
F-drtlior research on chronic and sublethal effects and on the
offects on co-,@Ti,@,,iunities of organisms will undoubtedly enhance
our understanding and should be strongly supported, but within
tile time frame of the implementation of water quality stand-
ards as dictated by the Federal Water Pollution Control Act
of 1972, it will. be acute toxicity data which will provide
the bases of water quality criteria.

TDENTIFICATION OF RELEV.1UNT_,,1jTA.NDAj1D.S -AND CRETERIA

This compilation is limited to criteria and standards for
marine and freshwater life, wildlife, recreation and aes-
thetics . Standards and criteria pertaining to water supplies
and a,7ricultural and industrial uses are not included. In
add;tl? on to water quality standards and criteria, federal
leuislation and effluent limitations are discussed because
they bear importantly on water qual-iLy.

FEDERAL WATER POLLUTION CONTROL ACT OF 1972

In addition to setting the goal of the elimination of the
discharge of pollutants by 1985, providing legislative
T 0
approval of a massive program. of water pollution control
technolo gy, and establishing a discharge permit system, the
Act (especially Title III) includes sections which have far-
reaching consequences for water quality standards and criteria.

The Act requires achievement of effluent limitations for point
sourcesY other than publicly owned treatment works, through
the "best practicable control technology currently availa 'ble",
CBPCTCA) by July 1, 1977; appropriate pretreatment for dis-
charges into public treatment facilities; and "secondary
treatment" of wastes from publicly owned treatment works
by the same date. Effluent limitations for point sources
requiring application of the "best available technology
economically achievable" (BATEA) must be achieved by July 1,
1983 and they must reflect significant progress toward the
goal of elimination of discharge of pollutants. Publicly
owned treatment works mu,st achieve "best practicable control"
by the 1983 date. The Environmental Protection Agency is
currently developing effluent limitations reflecting BPCTA
and BATEA levels for a number of classes of point sources
and for "secondary treatment". These are discussed below
under Effluent Limitations.

The Act requires EPA to review all state water quality
standards, water use classifications and the criteria on
which these are based (for all waters within state), and
to promulgate appropriate standards if a state does not

Appendix 15
332

adopt them. It also requires EPA to develop and publish
criteria for water quality accurately reflecting the latest
scientil'ic knowledge on health and welfare, aquatic organ-
Z> C@
isms and communities, and concentration and dispersal of
pollutants.

Other stipulations of the Act which bear on water quality
relate to enforcement, water quality inventories which must
be conducted by the states and EPA, oil and hazardous sub-
stances,- marine sanitation devices, and thermal discharges.

EPA WATER QUALITY CRITERIA

As directed by the Federal Water Pollution Control Act of
1972, the EPA released in October, 1973, "Proposed Water
Quality Criteria" to be used in the development of stand-
ards by the states. These criteria were to reflect the
latest scientific knowledge on: (1) all identifiable
effects of pollutants on human health, fish and aquatic
life, plant life, wildlife, shorelines and recreation;
(2) concentration and dispersal of pollutants; and (3)
effects of pollutants on biological community diversity,
productivity and stability, including factors affecting
rates of eutrophication and sedimentation.

These criteria are largely based on those developed at the
request of EPA by the Committee on Water Quality Criteria
of the Environmental Studies Board of the National Academies
of Science and Engineering (4) which were summarized in our
Interim Report. The EPA criteria vary little from those
proposed by NAS/NAE, and a full comparison of the two has
been published by the EPA (6).

Included for reference in this report are summaries of the
criteria for marine and freshwater aquatic life (Table 15-18),
wildlife (Table 15-19), and recreation (Table 15-20).

Although some of the criteria are specific numerical limits,
most of those pertaining to aquatic life are put in terms of
acute toxicity to species in the locality under considera-,
tion. They are of the typical form of an application factor
(usually 0.1 - 0.01) applied to the concentration of the
constituent in the water in question which causes death
within 96 hours to 50 percent (LCSO) of a test group of
the most sensitive important species in the locality under
consideration. This is often supplemented by a specific
more liberal numerical limit which should not be exceeded.
It should be noted that for the purposes of the criteria,
an "important species" is defined as an organism that is:
(1) commercially or recreationally valuable; (2) is rare
or endangered; (3) affects the well-being of valuable,
rare or endangered species; or (4) is critical to the
structure and function of the ecological system.

Appendix 15
333

TABLE 15-18
(D FE
wo SUMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LI

Parameter F r e s 1i w a t e rMarine F, estuarine
V
1. Acidity, Alkalinity and p1l

a. pH 6-9 6.5-8.S
no change of 0.5 above
seasonal extremes

b. Alkalinity 75% of natural --------

C. Acidity no addition -------

2. Dissolved Gases
a. Ammonia 0.05 LC50 0.1- LC50*
never >0.02 mg/l never >0.4 Tng/l
b. Chlorine 0.003 mg/1 6.1 LC50
O.OOS mg/l for 30 min. never >0.01 mg/l

c. Dissolved Oxygen Based on seasonal tem-, 6.0 mg/l except by
perature; minimum 4 natural phenomena
mg/1 at 310C
d. Hydrogen Sulfide 0.002 mg/1 0.1 LCSO
never >0.01 mg/l

e. Gas Pressure 110% atmospheric --------

*Means 0.1 *of LC50

TABLE 15-18 (cont'd)
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LIFE

Parameter Freshwater Marine & estu,:Irinc-
3. Inorganics (Ions and Free Elements/Compounds)
a. Aluminum ---------- 0.01 LC so, never >I.S mg/l
b. Antimony ---------- 0.02 LC50, never >0.2 mg/l
c. Arsenic ---------- 0.01 LCSO@ never >O.OS mg/l
d. Barium ---------- 0.05 LC50, never >1 mg/l
e. Beryllium ---------- 0.01 LC never I.S ma/l
50)
f. Bismuth ---------- none prescribed
g. Boron ---------- 0.1 LC so
h. Bromide ---------- 0.1 mg/l
(molecular)

(ionic) ---------- 100 mg/l
i. Cadmium 0.03 mg/l.in hard water 0.01 LCSO (0.001 96 hr LCSO
0.004 mg/l in soft water in presence of other
(one tenth of those where metals). never >0.01. mg/1)
salmonids or crustaceans
develop.)
j. Chromium 0.05 mg/1 0.01 LCSO, never >0.1 mg/l
C3 k. Copper 0.1 LC50 0.01 LCSO, never >O.OS mg/l
C.J

TABLE 15-18 (cont'd)
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LIFE

Parameter Freshwater Marine & estuarine

FA
3. Inorganics (Ions and Free Elements/Compounds (continued)

1. Fluorides ---------- 0.1 LCSO, never >1.S mg/1
M. Iron ---------- 0.3 mg/1

n. Lead 0.03 mg/l 0.02 LC50 24 hr average,
0.01 LC50, never 0.05 mg/l
o. Manganese ---------- 0.02 LC50, never >0.1 mg/l
p. Mercury 0.2 ug/1 0.01 LC50, never >0.1 ng/1
q. Molybdenum ---------- O.OS LC50
r. Nickel 0.02 LC50 0.02 LC50, never >0.1 mg/l
s. Phosphorus ---------- 0.01 LCS(), never >0.1 Aig/l
t. Selenium, ---------- 0.01 LC50, never >0.01 mg/l
u. Silver ---------- 0.05 LCSO, never >5.0 Ug/l
v. Thallium ---------- O.OS 20 day LCSO, never
>0.1 mg/l

w. Uranium ---------- 0.01 LC50, never >O.S mg/l
x. Vanadium ---------- 0.05 LC50
y. Zinc 0.005 LC50 0.01 LC50, never >0.1 mjj/l

TABLE 15-18 (cont'd)
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LIFE

Parameter Freshwater Marine estuarine

4. Organic Compounds

a. Cyanides O.OS LC@0, never >0.005 0.1 LCSO, never >0.01
mg/l mg/l
b. Linear alkylate O.OS LC50, never >0.2 ---------------------
sulfonates mg/l

C. Oils 1. not visible on surface 1. no visible film
2. emulsified concentrations 2. no odor or tainting
never "Ih 0. 05 LC50 3. no deposits on shores
3. fiexane extractable sub- or bottoms
stances in sediments, never
>1000mg/kg dry weight

d. Phthalate esters never >0.3 ug/l ---------------------

Organic Mercury never >0.2 ug/l --------------------
(average total never
>0.05 ug/1)

f. Polychlorinated not >0.002 ug/l --------------------
biphenyls not >0.5 ug/g in tissue
g. Phenolic compounds O.OS LC50, never >0.1 ---------------------
Mg/l

S. Pesticides

a. General 0.01 LC50 0.01 LC
so

TABLE 15-18 (contd)
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LIFE

00 H.
Parameter Freshwater Mari.ne estuarine

5. Pesticides (continued)

b. Organochlorines Recommended permissible
maximum concentration (pg/1)
Aldrin 0.01
DDT 0.002
TDE 0.006
Dieldrin 0.00S
Chlordane 0.04
Endosulfan 0.003
Endrin 0.002
Heptachlor 0.01
Lindane 0.02
Methoxychlor 0.00S
Toxaphene 0.01

c. Organophosphates
Azinphosmethyl 0.001 -------------
Ciodrin 0.1
Coumaphos 0.001
Diazinon 0.009
Dichlorvos 0.001
Dioxathion 0.0,9
Disulfate 0.05
Dursban 0.001
Ethion 0.02
EPN 0.06
Fenthion. 0.006
Malathion 0.008
Mevinphos 0.002
Naled 0.004

TABLE 15-18 (cont'd)
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR AQUATIC LIFE

Parameter Freshwater Marine estuarine

S. Pesticides (continued)

c. Organophosphates (continued)
Oxygenmeton methyl 0.7
Parathion 0.03
Phosphamidon 0.03
TEPP 0.3
Trichlorophon 0.002

d. Carbamates --------------
Carbaryl 0.02
Zectran 0.1

e. Herbicides, Fungicides ------------
and Defoliants
Aminotriazole 300
Dalapon 110
Dicamba 0.2
Dichlobenil 37
Dichlone 0.7
Diquat 0.5
Diuron 1.6
2-43, D (BEE) 4
Fenac (sodium salt) 45
Silver (BEE) 2.5
Silver (PGBE) 2
Simazine 10

f. Botanicals -------------
Allethrin 0.002
Pyrethruni 0.01
Rotenone 10.0

c.n

TABLE 15-18 (cont'd)
(D
SUMMARY OF PROPOSED EPA WATER QTJALITY CRITERIA FOR AQUATIC LIFE

@_j Parameter Freshwater Marine & estuarine

6. Physical (Except Temperature)

a. Color <10% change in compensation ---------------
point, no more than 10% of
biomass of photosynthetic
organisms below compensation
point

b. Turbidity ---------------

7. Radioactivity organisms harvested must organisms harvested
not exceed radiation must not exceed
protection guidelines radiation protection
guidelines

8. Solids

a. Total dissolved solids no significant changes in ---------------
and hardness biological communities

b. Suspended and settle- not >80 mg/l ---------------
able solids
9. Tainting Substances bioassays and organoleptic ---------------
tests
10.1 Temperaturc complex criteria qdepending increase not >2.20C
on thermal tolerances and (4.OOF) during So t.-
requirements of sensitive May or 0.80c.(l.s
species during June-August

TABLE 15-19
SUMMARY OF PROPOSED EPA WATER QUALITY CRITERIA FOR WILDLIFE

Parameter Freshwater Marinel

1. Acidity, Alkalinity and pH
a. pli same as for aquatic life ------
b. Alkalinity and Acidity alkalinity 30-130 mg/l ------
departure from natural
conditions not >50 mg/l

2. Light Penetration
<10% change in compensation ------
point, no more than 10 o/oo
of biomass below compensation
point

3. Solids

a. Salinity close to natural conditions, ------
no rapid fluctuations

b. Settleable solids should be minimized -------

4. Specific Harmful Substances

a. Toxins (botulism factors should be managed as ------
poisoning) to minimize risk of disease
outbreak

b. Oils no visible floating oils ------
C. DDT and derivatives I mg/kg (wet weight) in So jig/kg/wet weight
aquatic plants & animals in fiS11 C011-SUMod
by birds
CA

TABLE 15-19 (cont'd)
SUMMARY OF PROPOSED EPA WATER QUALITYCRITERIA FOR WILDLIFE

0
wa.
Parameter Freshwater Marinel

Ca 4. Specific Harmful Substances (continued)

d. AldrinJ, dieldrin, endrin, ----------- sum of S mg/kc, (wet
C,
and heptachlor weight) in fish eaten
by birds

e. Other chlorinated ---------- 50)19/kg (wet weight)
hydrocarbons in fish eaten by birds

f. Polychlorinated biphenyls no increase O.S mg/kg (wet weight)
(PCB's) in fish eatbn by birds

g. Mercury 0.5 ug/g in fish ------

S. Temperature
no.changes in natural. ------
freezing patterns and
dates

Except for specific substances listed., the marine aquatic life criteria are
acceptable for application to coastal and marine waters inhabited by wildlife.
The freshwater wildlife criteria are in general acceptable for application to
estuarine wildlife.

TABLE 15-20
PROPOSED EPA WATER QUALITY CRITERIA FOR RECREATIONAL WATERS

A. Aesthetic Considerations

1. Aesthetics - General
a. All surface waters should be capable of supporting
life forms of aesthetic value

b. Surface waters should be "free" of
(1) materials that form objectionable deposits
(2) floating debris, oil, scum, etc.
(3) substances producing objectional color, odor,
taste or turbidity
(4) materials which produce undesirable physiol-
ogical responses in humans, fish and other
animal or plant life
(5) substances or conditions which produce
undesirable aquatic life

2. Nutrient (Phosphorus)
-- no limit'is prescribed

B. Recreational Waters

1. Clarity secchi disc visible at 4 ft.
for bathing and swimming waters
bottom visible in "learn to
swim" areas
equal to minimum required
safety standards in diving
areas

2. Microorganisms
a. Bacteriological indicators (fecal coliform
bacteria)

as a minimum be suitable for
recreation where there is
little risk of ingestion (not
to exceed average of 2000/100
ml or maximum of 4000/100 ml)
for intimate contact recreation
average of 200/100 ml and <10%
of samples during 30 day period
>400/100 ml

343

TABLE 15-20 (cont1d)
PROPOSED EPA WATER QUALITY CRITERIA FOR RECREATIONAL WATERS

B. Recreational Waters (continued)

b. Viruses
no limit prescribed

3. pH
bathing waters 6.5 to 8.3
never <5 or >9

4. Shellfish
fit-for human consumption
as per "Sanitation of
Shellfish Growing Areas"

S. Temperature
<300C (860F) in bathing or
swimming waters except where
caused by natural conditions

AppendIx 15
344

The practice of establishing criteria based on toxicit-y da ta
for the locality under conside-ration has the desirable attri-
bute of allowing the criteria (and thus standards) to reflect
local variability, however it also may cause confusion in the
setting and enforcement of standards and may result in uneven
application of the law. However, given the lack or' data or.
C@
the effects of many pollutants and the widely variable natu-
ral conditions, there seems no reasonable alternative to this
practice, at least for some time to come.

It remains to be seen just how the proposed EPA criteria are
to be used in setting water quality standards. EPA plans
that they will be incorporated into revised state water
quality standards under the direction of EPA Regions by
means of policy guidelines developed by the EPA Office of
Water Planning and Standards. These guidelines have not yet
C.
been fully developed but they will have provisions for waters
to be exempted from specific criteria on a case-by-case basis
for specified periods when naturally occurring conditions
exceed limits of EPA criteria or other extenuating conditions
prevail to warrant such exemptions.

EFFLUENT LIMITATIONS

EPA has now promulgated or proposed effluent guidelines,
limitations and new source standards of performance for
,industrial categories. These categories are listed in
Table 15-21,together with reference to the publication of
the final or proposed limitations. Limitations are being
formulated for several other industrial catecories to be
finalized within a year and these are also listed in Table
15-@;21.

The effluent guidelines, limitations and standards of
performance are generally complex, varying with industrial
subcategory and usually stated in terms of mass emission
per unit product. Thus, they are difficult to interpret
in terms of water quality since it is often impossible even
to deduce from them the concentrations of pollutants in
effluents., muchless those that would result in the environ-
ment. Furthermore, they are typically based on standard
waste treatment parameters such as biological and chemical
oxygen demand, suspended and dissolved solids and pH, rather
than considerations of the potentially harmful chemical con-
stituents of these wastes.

We have not here attempted to summarize all of the proposed
effluent limitations. Some are discussed under the detailed
evaluations of criteria and standards related to oil and
chlorine. However, we should point out that the impact of
these reaulations on water quality may be substantial for
two reasons: (1) they are relatively more specific and
enforceable than water quality standards and (2) they mostly

Appendix-15-
345

(D TABLE 15-21
INDUSTRIAL CATEGORIES AND EFFLUENT LIMITATIONS

Industrial Categories for Which Limitations Code of Federal
Have Been Promulgated or Proposed (continued) Regulations Reference

Textile Mills Proposed 39 FR 4628
39 FR 24750
Steam Electric Power Plants Proposed 39 FR 8294
39 FR-17449

Industrial Categories for Which Limitations Are
Being Formulated

Group I, Phase II

Rubber Processing
Electroplating
Timber Products Processing
Inorganic Chemicals Manufacturing
Plastic and Synthetic Materials Manufacturing
Ferroalloy Manufacturing
Organic Chemicals Manufacturing
Nonferrous Metals Manufacturing
Phosphate Manufacturing
Fertilizer Manufacturing
Asbestos Manufacturing
Meat Products and Rendering Processing
Grain Mills
Canned and Preserved Seafood Processing
Glass Manufacturing
Sugar Processing
Iron and Steel Manufacturing
Pulp,.Paper and Paperboard Mills
Builders Paper and Board Mills

TABLE 15-21 (cont'd)
INDUSTRIAL CATEGORIES AND EFFLUENT LIMITATIONS

Industrial Categories for Which Limitations Code of Fedeyal
Have Been Promulgated or Proposed Regulations Reference

Group I, Phase I

Glass Manufacturing 40 CFR 426
Cement Manufacturing 40 CFR 411
Feedlots, 40 CFR 412
Phosphate Manufacturing 40 CFR. 422
Rubber Processing 40 CFR. 428
Ferroalloy Manufacturing 40 CFR 424
Inorganic Chemical Manufacturing 40 CFR. 41S
Electroplating 40 CFR 413
Asbestos Manufacturing 40 CFR 42 7
Meat Product and Rendering Processing 40 CFR 432
Plastic and Synthetic Materials Manufacturing 40 CFR. 416
Nonferrous Metals Manufacturing 40 CFR 421
Sugar Processing 40 CF1Z 409
Canned and Preserved Fruits and Vegetables Processing 40 CFR 407
Grain Mills 40 CFR 406
Soap and Detergent Manufacturing 40 CFR 417
Fertilizer Manufacturing 40 CFR 418
Petroleum Refining 40 CFR 419
Dairy Product Processing 40 Cj'R 40S
Leather Tanning and Finishing 40 CFR 425
Pull), Paper and Paperboard Mills 40 CFJZ 430
Organic Chemicals Manufdcturing 40 CFR 414
Builders Paper and Board Mills 40 CFR 431
Canned and Preserved Seafood Processing 40 CFR 408
Timber Products Processing 40 CFR 429
(D Iron and Steel Manufacturing 40 CFR 420

TABLE 15-21 (cont'd)
INDUSTRIAL CATEGORIES AND EFFLUENT LIMITATIONS
(D

00H.

Industrial Categories for Which Limitations Are
Being Formulated (continued)

Group II

Auto and Other Laundries
Paving and Roofing Materials
Transportation Industries
Paint and Ink Formulation and Printing
Fish Hatcheries and Farms
Canned and Preserved Fruits and Vegetables Industry
Miscellaneous Chemicals
Miscellaneous Food and Beverages
Machinery and Mechanical Products Manufacturing
Coal Mining
C.
Petroleum and Gas Extraction,, Handling Storage and Residues Disposal
Mineral Mining and Processing Water Supply
Ore Mining and Dressing Stream Supply
Structural Clay Products
Pottery and Related Products
Concrete, Gypsum and Plaster Products
Furniture and Fixtures Manufacturing
Point Source Discharge Categories Not Otherwise Covered

require substantial improvements in waste treatment by 1977
and virtual elimination of discharge by 1983. For example,
the effluent limitations for the steam electric power indus-
try stipulate no thermal discharge into natural waters, and
thus the virtually complete reliance on recirculating cooling
systems (c'ooling towers, etc.), by 1983. It is hard to
imagine the proffering of a water quality criterion which
C,
would have an equivalently drastic effect.

With so much at stake.. the development of the effluent limita-
tions has been surrounded by substantial controversy. First,
there is the matter of the degree to which economic, social
and non-water quality environmental impacts should be taken
into account. These were taken into account by EPA in the
-formulation of the effluent limitations as reauired under
the Act (PL 92-500). However it has been fur@her sua.-ested
that a procedure be established whereby, when applying the
limitations in the issuance of discharge permits, other
factors, such@as plant age, size and location and economic
impacts are taken into account. This so-called "matrix
approach" would mean that the limitations would be no more
t@an guidelines on which wide discretional variances could
be applied. Although the matter is still far from resolved,
EPA has issued a policy statement on variances from the
effluent limitations (7).

The second controversy involves the relationship of the
effluent limitations to water quality. It is important
to note that compliance with the effluent limitations does
not provide exemption from water quality standards. The
Act specifically states,that whenever discharges of pollu-
tants, with the application of required effluent limitations,
would'interfere with the attainment or maintenance of water
quality, effluent limitations shall be established which can
reasonably be expected to contribute to the attainment or
maintenance of water quality /Slection 302 (aTT and further
requires.the states to identi-Ey those waters-for which the
effluent limitations are not stringent enough to implement
applicable water quality standards /97ection 303 (dT7. But
the question has been raised that, 'En light of the-substan-
tial costs of meeting the effluent limitations, is it justi-
fiable to meet limitations when it would result in little
or no improvement in water quality. With no industrial
category is this controversy so intense as with the power
generating industry. The cost of meeting the 1983 limita-
tions has been estimated by the industry to be $48 billion,
and industrial representatives argue that this would result
in little environmental improvement,for the receiving waters
of many plants. To further complicate matters, another
section of the Act /Yection 316 (aTT which pertains spe-
cifically to thermal discharge allUws the exemption of'
=
lants from the effluent limitations 'if the operators can
onstrate a lack of environmental damage due to their
operation.

Appendix 15
349

The Act also requires that EPA define the ef.-Huent limitations
for-11secondary treatment" from publicly owned sewage treatment
works. These limitations must be achieved by federally fi-
nanced facilities b July 1, 1977. These limitations are
given in Table 15-21.

TOXIC POLLUTANT STANDARDS

Section 307 (a) of the Federal Water Pollution Control Act
requires that the Administrator of EPA publish a list of
"toxic pollutants", with effluent standards for such pollu-
tants., which take into account their toxicity, persistence,
degradability and importance of organisms which might be
affected by these pollutants.

Proposed regulations on toxic pollutant effluent standards
have been published (8) and are summarized in Table 15-23.
These standards govern the concentrations of nine pollutants
in effluents and set limits on mass emission rates. The
limits depend on the size or flow rate of the water body.

OCEAN DUMPING CRITERIA

The Marine Protection, Research and Sanctuaries Act (P.L.
92-532), as well as the Federal Water Pollution Control Act
(P.L. 92-500), requires the formulation of criteria on which
decisions as to issuance of permits for ocean dumping may be
CP
based. The EPA has therefore published interim ocean dumping
criteria (9) which shall apply to the granting of permits for
dumping materials at approved dumping sites. Two of the ap-
C,
proved sites lie off the mouth of Chesapeake Bay. Further-
more it seems probable that these criteria will be applied
to the disposal of solid wastes, principally dredge spoil,
C.
within the Bay system. Thus they are of great importance
to water quality in the Bay and of obvious importance to the
interests and responsibilities of the Corps of Engineers.

The interim ocean dumping criteria are summarized in Table.
15-24.

STATE WATER QUALITY STANDARDS

.Maryland

New water quality standards have recently been promulgated
C,
by the Maryland Department of Water Resources (10) and are
reproduced in Table 15-25. The Department of Water Resources
has also issued ground water standards, general effluent
limitations, regulations pertaining to the prevention of
oil pollution, and requirements for discharge permits
implementing the National Pollutant Discharge Elimination
System. These recent new regulations and policy statements
reflect the requirements of the Federal Water Pollution
Control Act.

Appendix 15
350

TABLE 15-22
EFFLUENT LIMITATIONS TO BE ACHIEVED BY ALL
SECONDARY FEDERALLY FINANCED TREATMENT PLANTS

Biological Oxygen Demand (BODS)
-- maximum monthly average, 30 mg/l

Suspended Solids

-- maximum monthly average, 45 mg/l

Fecal Coliform Bacteria

maximum monthly average,-200/100 ml
maximum weekly average, 400/100 ml

Appendix 15
351

TABLE 15-23
PROPOSED EPA TOXIC POLLUTANT EFFLUENT STANDARDS (8)
top.

Low flow >10 cfs
Low flow <10 cfs Lakes >500 acres
Toxic Pollutant Lakes :@.SOO acres Coastal waters

1. Aldrin & Dieldrin No discharge 0.5 ug/l fresh water
S.5 ua/1 salt water

2. Benzidine No discharge 1.8 ugll

3. Cadmium No discharge 40 ug/l fre sh water
320 ug/l salt water

4. Cyanide No discharge 100 ug/l

S. DDT (including DDD and DDE) No discharge 0.2 ug/l fresh water
0.6 ug/l salt water

6. Endrin No discharge 0.2 ug/l fresh water
0.6 ug/l salt water

7. Mercury No discharge 20 ug/l fresh water
1-00 ug/l salt water

8. Polychlorinated Biphenyls (PCB's) No discharge 280 ug/l fresh water
10 ug/1 salt water

9. Toxaphene No discharge 1.0 ug/l

Note: Limits are also set on mass emission rates. For particulars
the EPA regulations should be consulted.

TABLE 15-24
SUMMARY OF EPA CRITERIA FOR THE EVALUATION
OF PERMIT APPLICATIONS FOR OCEAN DUMPING (9)

Prohibited materials

Completely prohibited:

high-level radioactive-wastes
radiolouical chemical or biological warfare agents
materials insufficiently described to permit eval-
uation of impact
persistent inert materials which may float or remain
in suspension

Prohibited in all but trace concentrations:

organohalogen compounds (total concentration not
>0.01 toxic concentration)
mercury and mercury compounds (not >0.75 mg/ka in
solid phase or 1.S mg/k- in liquid phase)
cadmium and cadmium compounds (not >3.0 ma/kg in
solid phase or 6.0 mg/kg in liquid phase)
oil taken on board for dumping (should not produce
visible sheen in undisturbed water sample)

Materials requiring special care /p-ermit based on demon-
stration by bioassay (0.01 of 76-hr LC50) that adverse
effects will be minimalT

elements- ions or compounds of arsenic, lead,
copper, zinc, selenium, vanadium, beryllium,
chromium and nickel
organosilicon compounds
inorganic processing wastes including cyanides,
fluorides, titanium dioxide, and chlorine
petrochemicals and organic chemicals
biocides
oxygen consuming and/or biodegradable organic matter
lowolevel radioactive wastes I
toxic pollutants and hazardous substances
materials immiscible with seawater

Hazards to fishing and navigation

wastes must not interfere with fishing or navigation

Appendix 15
353

TABLE 15-24 (cont'd)
SUMMARY OF EPA CRITERIA FOR THE EVALUATION
OF PERMIT APPLICATIONS FOR OCEAN DUMPING (9)

Large quantities of materials

dumping must be controlled to-prevent damage to the
environment or to amenities

Acids and alkalis

no adverse affects on pH
no adverse synergistic effects

Containerized wastes

materials disposed of must decay, decompose or radio-
decay to environmentally innocuous material within the
life expectancy of container
only short-term localized effects would result from
rupture
must not pose hazard to fishing or navigation

Materials containing living organisms

must not extend range of biological pests,, viruses,
pathogenic micro-organisms, etc.
must not degrade uninfected areas
must not introduce viable species not indigenous to an
.area

Dredged material

Unpolluted material
considered unpolluted if (1) essentially-sand and
gravel, (2) water quality at dredging site is ade-
quate according to State water quality standards
for propagat io n of fish, shellfish, and wildlife
and associated biota typical of a healthy ecosystem,
or (3) it produces a standard elutriate in which the
concentration of no major constituent is 1.5 times
the concentration in water at the disposal site

Appendix 15
3 5; 4

TABLE 15-24 (cont'd)
SUMMARY OF EPA CRITERIA FOR THE EVALUATION
OF PERMIT APPLICATIONS FOR OCEAN DUMPING (9)

Dredged material (continued)

Polluted material

so classified if it does not'meet above criteria
can be disposed of if it can be shown that the
place, time, and conditions of dumping are such
as to produce a minimum impact on environment

Appendix 15
355

Virginia

The Virginia State Water Control Board's water quality
standards are., like those in Maryland, based on water
use classification. There are six 'Major classes based
on waterbody type and two subclasses based on suitability
lor primary or secondary contact recreation (Table 3-9).
Furthermore the Water Control Board has promulgated special
standards for particular bodies of water. Because of the
obvious importance to Chesapeake Bay, the special bacteri-
ological standards for shellfish growing areas are included
in Table 3-9.

In general, the state water quality standards are far more
limited in scope than the new EPA water quality criteria.
They concern at most only dissolved oxygen, teriperature, pH,
turbidity, and coliform bacteria. State bacteriological
standards comply with the EPA criteria and pH standards are
slightly more'restrictive. However, state dissolved oxygen
standards are lower than those recommended by EPA. Temper-
ature standards are difficult to compare to those complex
criteria proposed by EPA. It remains to be seen the degree
to which EPA will require states to alter their standards
to comply with the criteria and to adopt new standards for
the myriad of other parameters for which there are criteria.

.Appendix 15
356

TABLE 15-25
WATER QUALITY STANDARDS FOR THE STATE OF MARYLAND

REGULATION 08.05.04.03 - RECEIVING INATER QUALITY STANDARDS

This regulation is effective May 1, 1973

The followina receiving water quality standards are
established to protect the uses indicated. Where the waters
of the State* are, or may be, affected by discharges* from
point sources*, these standards shall apply outside of a
mixing zone* designated by the Administration*.

CLASS I WATERS

Water Contact Recreation and Aquatic Life

Bacteriological Standards

There shall be no sources.of pollution* as determined by
a sanitary 'survey, and the fecal coliform* content of these
waters shall not exceed a log mean of 200/100 ml.

Dissolved Oxygen Standard

The dissolved oxygen concentration must be not less than
4.0 mg/liter at any time, with a minimum daily average of not
less than S.0 mg/liter, except where, and to the extent that,
lower value's occur naturally*.

Temperature Standard

1. Thermal effects shall be limited and controlled so
as to prevent:

a. Temperature changes that adversely affect aquatic
life;

b. Temperature changes that adversely affect spawn-
ing success and recruitment; and

c. Thermal barriers* to the passage of fish.

2. Temperature-elevations above natural must be limited
to 50F. and the temperature must not exceed 900F,
outside of designated mixing zone.

Appendix 15
357

TABLE 15-25 (cont'd)
WATER QUALITY STANDARDS FOR THE STATE OF MARYLAND

3. This limitation of temperature cnanges in Class I
waters does not preclude tile discharge of warmed
water. Warming of a -oortion of a body of water is
C,
permissible if it will not,produce substantial
detriment and if the.volune of the new temperature
is of such size and duration that the exposure of
organisms or life staaes thereof,, is less than the
time associated with deleterious biological effects
at that particular temperature.

DIH Standard

Normal pH values must not be less than 6.5 nor greater
than 8.5, except where--and to the extent-that--pH values
outside this range occur naturally.

Turbidity Standard

1. Turbidity shall not exceed levels detrimental to
aquatic life; and

2. Within limits of Best Practicable Control Technology
Currently Available*, turbidity shall not exceed for
extended periods of time those levels normally pre-
vailing during periods of base flow* in the surface
waters; and

3. Turbidity in the receiving water* resulting from any
0
discharge shall not exceed 50 JTU (Jackson Turbidity
Units) as a monthly average, nor exceed 150 JTU at
any time.

CLASS II WATERS

Shellfish Harvesting

Bacteriological Standards

1. The Most Probable NuTber (NPN) of fecal colif orm organisms
must not exceed 14/100 ml, as a median value and not
more than 10 percent of thesamples shall exceed an
MPN of 43J100 ml for a five-tube decimal dilution
test (or 49/100 ml, where the three-tube decimal
dilution test is used), and.

Appendix 15
358

TABLE 15-25 (cont'd)
WATER QUALITY STANDARDS FOR THE STATE OF MARYLAND

2. Must also comply with the sanitary and bacteriolog-
ical requirements as set forth in the 'Latest edition
of "National Shellfish Sanitation Pro-ran Manual of
Operations".

Dissolved Oxygen Standard

Same as for Class I waters.

Temperature Standard

Temperature elevations above natural must be limited to
40F in September through May, and to 1.50F in June through
August, outside of designated mixing zones.

pH Standard

Same as for Class I waters.

Turbidity Standard

Same as for Class I waters.

CLASS III WATERS

Natural Trout Waters

Bacteriological Standards

Same as for Class I waters.

Dissolved Oxygen Standard

The dissolved oxygen concentration must be not less than
5.0 mg/liter at any time, with a minimum daily average of not
less than 6.0 mg/liter, except where, and to the extent that,
lower dissolved oxygen values occur naturally.

Temperature Standard

1. No significant thermal changes; and

Appendix 15
359

TABLE 15-25 (cont'd)
WATER QUALITY STANDARDS FOR THE STATE OF MARYLAND

2. TemDerature must not exceed 681F bevond such distance
from any point of discharge as specified by the
Administration, except where, and to the extent that,
higher temperature values occur naturally.

pH Standard

Same as for Class I waters.

Turbidity Standard

Same as for Class I waters.

CLASS IV WATERS

Recreational Trout Waters

Bacteriological Standards

Same as for Class I waters.

Dissolved Oxygen Standard

Same as for Class I waters.

TemDerature Standard

1. Thermal effects shall be limited and controlled so
as prevent:

a. Temperature changes that adversely affect aquatic
life;

b. Temperature changes that adversely affect spawn-
ing success; a4d

c. Thermal barriers to the passage of fish.
2. Temperature must not exceed 75OF beyond such distance
from any point of discharge as specified by the
Administration, except where, and to the extent that,
higher temperature values occur naturally.

Appendix 15
360

TABLE 15-25 (cont'd)
WATER QUALITY STANDARDS FOR THE STATE OF MARYLAND

pH Standard

Same as for Class I waters.

Turbidity Standard

Same as for Class I waters.

The meaning of this term is described in Regulation
08.05.04.01 DEFINITIONS

Appendix 15
361

XT
.Puaddv

C-3 :F@

.4 IV X: :i@ r-4 @xl n m t@ 0 0
0 r- 0 0 0 0 " 0 tf) w Iri r+
r+ r+ z 0 0 P) r+ z

p r+ r+ (A r+ P) CD
p p r+ C+ 0 0
I.J. 0 03 P n =M
@:5 o ti (n 0 (D H
0 Ln r+ :;@ " (D (n p W P)
@-t P3 rz: - ::;- H. 0
0 @71- UI 0 0 :j ::I
tz CD z " 0
r+ t@4 0 (D cn
0 Cn r.A r+ p X:
@J C+ 0 0 @4- @-j
0 Z F-I 0
r+ >
(D r+
0 It @5 p 0 0 CD
Ln Z@ (n
p
r+ r+
CD @:;, @5
0 0

C% vi 4:@- 4@-- 4::b Ln
CD cl *CD

C\ Lrl L'I Ln

C:l C:l CD

0\ C\ CN t-I
F-3

00 00 co 00 00 00

Ln
'Un

z
t.n Ul C)
f--@ r--@ >
C-4 cn C-4
I (D r+ (D
I LIT Id
It (D

> > o

oro

CD C)

TABLE 15-26 (cont'd)
WATER QUALITY STANDARDS FOR THE COMMONWEALTH OF VIRGINIA

SUBCLASSES TO COMPLEMENT MAJOR WATER CLASS DESIGNATIONS

Subclass A

Waters generally satisfactory for use as public or municipal
water supply, secondary contact recreation, propagation of
fish and aquatic life, and other beneficial uses.

Coliform Organisms. Fecal coliforms (multiple-tube fermenta-
tion or MF count) not to equal or exceed 2000/1000 ml in more than 10% of
samples.

Monthly average value not more than 5000/100 nil (MPN or MF
count). Not more than 5000 MPN/100 ml in more 20% of
samples in any month. Not more than 20,000/100 ml in more
than 5% of such samples.

Subclass B

Waters generally satisfactory for use as public or municipal
water supply, primary contact recreation (prolonged intimate
contact; considerable risk of ingestion), propagation of fish
and other aquatic life, and other beneficial uses.

Coliform Organisms - Fecal coliforms (multiple-tube fermenta-
tion or MF count) within a 30 day period not to exceed a log
mean of 200/100 ml. Not more than 10% of samples within a
30-day period will exceed 400/100 ml.

Monthly average not more than 2400/100 ml (MPN or MF count).
Not more than 2400/100 ml in more than 20% of samples in any
month. Not applicable during, nor immediately following
periods of rainfall.*

*With the exception of the coliform standard for shellfish
waters, the enforceable standards will be those pertaining
to fecal coliform organisms. The MPN concentrations are
retained as administrative guides for use by water treatment
plant operators.

Appendix 15
363

TABLE 15-26 (cont'd)
WATER QUALITY STANDARDS FOR THE COMMONWEALTH OF VIRGINIA

Special Standards for ";@@llfish Growing Areas

In those sections Of Class IA., IB, IIA and IIB waters within
this State where leased private, or public Shellfish beds are
present, the following bacterial Sta'ndards shall be estab-
lished in addition to other bacterial standards adopted for
the Protection of primary or secondary recre'ation:

Coliform organisms - The rnledian IMPN shall not exceed
70/100 ril, and not more than 10% of the sanples ordi-
narily shall exceed an IMPN of 230/100 ml for a 5-tube
decinial dilution test Cor 330/100 ml, where a 3-tube
decimal dilution is used) in those portions of the
area most probably exposed to fecal contamination
during the most unfavorable conditions.

In addition., the shellfish area is not t o be so
contaminated by radionuclides, pesticides, herbi-
cides or fecal material so that consumption of the
shellfish might be hazardous.

REVIEW OF STANDARDS AND CRITERIA RELATED TO OIL

A large number of Federal and State laws and regulations,
as well as water quality standards and criteria, relate to
the discharge of oil into surface waters. In addition,
several international agreements regulate the discharge
of oil from ships at sea; however, these apply to inter-
national waters outside of the concern of this report.

Appendix 15
364

STANDARDS AND CRITERIA

Congress has delcared it a policy of the United States
that there should be no discharges of oil into or upon
the navigable waters, contiguous zones and adjoining
shorelines of the United States (11). The difficulty
of implementing this policy is manifest in the plethora
of overlapping laws and regulations concerning the dis-
charge of oil. A summarization of the various Federal
legal authorities relative to oil pollution control is
given in Reference 12. The two most important legal
authorities are the Federal Water Pollution Control
Act, as amended and the Oil Pollution Act of 1961 as
amended. The former Act largely supercedes the latter
with regard to internal navigable waters such as the
Chesapeake Bay. The Federal Water Pollution Control
Act Amendments of 1972 (PL 92-500) prohibit the dis-
charge, in harmful_quantities, of oil to the waters of
the U.S. The Act establishes fines and penalties for
prohibited discharges., failure to report such discharges,
and other violations of regulations and makes the discharger
liable for removal costs (11). Based on the authority of
this Act, various pollution prevention regulations (12)
and contingency plan s (13) have been promulgated.

A key question-in terms of both minimizing environmental
impact and implementation of these regulations concerns
the definition of "harmful quantities" of oil. PL 92-500
requires that the President determine "those quantities of
oil and any hazardous substance, the discharge of which
. will be harmful to the public health or welfare
Wth*e United States, including but not limited to, fish.,
shellfish, wildlife, and public and private property,
shorelines and beaches." The resultant regulitions
issued by EPA (12, 14) define harmful discharges as those
which: 1) violate applicable water quality standards or
2) cause a film or sheen upon or discoloration of the
surface of the waters or adjoining shorelines or cause
a sludge or emulsion to be deposited'.beneath the surface
of the water or upon the adjoining shorelines. Exempt
from this definition are discharges of oil from a properly
functioning vessel engine.

Appendix 15.,
865

TAis general standard of no visible sheen or sludge is similar
to the relevant state water quality standards., and EPA cri--
teria. For example, the Maryland general standards state that
waters shall be free from "floating debris, oil, grease, scum,
and other floating materials ... in amounts sufficient to be
unsightly-to such a degree as to create a nuisance, or inter-
fere directly or indirectly with'water uses (10).11 The EPA
water quality criteria (5) include a criterion of no visible
sileen or deposits on the shore or bottoms. The criteria for
marine and estuarine waters further stipulate that no odor or
tainting of fish and shellfish occur and those for fresh wa-
ters include bioassay-determined concentrations (0.05 96 hr
LC@o emulsified concentration) and a maximum level of 1000
mg kg dry weight of hexane extractable substances ("oil and
grease") in sediments. Criteria set by EPA for determining
the acceptability of dredged spoil overboard disposal stip-
ulate a maximum of 1500 mc,/kg dry weight (9).
C. 0

Thus the applicable standards and criteria rely, for the Y,-,ost
part, on visual detection of oil in the environment-or, at
bast, gross chemical analysis and, except for the bioassay
criterion for freshwaters, are not based on biological ef-
fects. As will be discussed below, this is attributable to
the complex and variable nature of oils and a general lack
of understanding of the fate and effects of oil in aquatic
environments, as well as the necessity for a quick and,prac-
tical method of detection.

The laws and regulations discussed to this point are geared,
for the most part, to the control of accidental or irregular
discharges of oil from ships and offshore and onshore oil
handlina facilities. Oil nay also be introduced into the
aquatic environment as chronic or continuous discharges from
industrial processes, domestic sewage plants and land runoff.
Relatively few water*quality or discharge standards are aimed
at controlling these chronic discharges which often are not
detectable as slicks or surface films. Effluent standards
for discharlae of oil have been proposed for only a few of
the industrial categories considered by EPA -- this despite
the fact that oil is a wastewater constituent of many indus-
trial processes.

The most obvious industrial category for discharge of oil is
pet.roleum refining. Only one refinery currently discharges
into tidal waters of Chesapeake Bay, however several others
Ilave been proposed. Effluent limitations guidelines have
been promulgated covering total discharge, storm runoff and
treated ballast for several industrial subcategories CTable.
15-27. The refining discharges are given in terms of allow-
able emission per volume of product processed (i.e. in
'Kilograms of oil and grease in the wastewater compared to
the volume of oil entering the refinery), and are difficult
to relate to more familiar effluent concentrations. Using

Appendix 15
366

TABLE 15-27
EFFLUENT LIMITATION GUIDELINES FOR OIL AND GREASE
DISCHARGES FOR THE PETROLEUM REFINING INDUSTRY (15)

Industrial BPCTCAl BATEA2 New Sources
Subcate-ory (in kg/1000 cu m of feed product)
- r, - ---

A Topping
M
'lax.
daily 0.34 1.6
IMax. ave. 2.2 0.28 1.3

B. Low Cracking
Max. daily 4_0 0.Sl 2.6
.%-lax. ave. 3.2 0.40 2.1

C. High Cracking
Max. daily 5.0 0.68 3.3
Max. ave. 4.0 0.54 2.6

D. Petrochemical
Max. daily 6.2 0.74 3.6
IN-lax. ave. 5.0 O.S9 2.8

E. Lube
,vj,ax. daily 8.6 1.4 7.1
Max. ave. 6.9 1.1 5.7

F. Integrated
Max. daily 10.8 1.5 7.4
1
Max. ave. 8.6 1.2 5.9

Special Allocations BPCTA BATEA New Sources
(in ka/cu m Of flow)

Stormwater runoff
Max. daily 0.010 0.002 0.010
Max. ave. 0.008 0.0016 0.008

Ballast water
Max. daily 0.40 0.002 0.010
Max. ave. 0.008 0.0016 0.008

1 BPCTCA: Best practica ble control technology currently
available; standards to be achieved by 1976.
2 BATEA: Best available technology economicall y achieva ble;
standards to be achieved by 1983.

Appendix 15
367

the ratios for product: wastewater volumes used in the
preparation of the guidelines (16) the following are
approximations of oil and grease effluent concentrations
for all industrial subcategories:

BPCTCA BATEA New Source

Maxi-,-1-urn dai1v 10 ppm. 1.5 P-?M 6 -ppm
1 .1
1%,Iaxinum average 8 ppm 1.0 ppm 5 ppm

Ho,@@,ever, as will be later discussed, mass emission rates
based on plant capacity may be more valuable in assessing
im-oact. Thus -lie oil refinery located on the York River
L
whtlc';,l rroduces 50,000 barrels/day would be required to
disc'Aarge on the avera-e no raore than 32 kg (70 lbs. or
rouohly 10 gallons) of oil and grease per day. However
the Vi--,,,Tinia Water Control Board (17) estimates a mass
emission rate of 707 lb/day (320 k-/day) from this facil-
ity,* despite the low effluent concentrations reported
(1-8 ppm).

A new "high cracking" refinery, say of 100,000 barrels/day
capacity, locating on the Chesapeake Bay would be required
to discharge no more than an average of 41.31 kg/day oil
and grease and be required to cut that to 8.58 kg/day by
1983. Thus, its yearly discharge would be 15 metric tons
(ca. 4,500 gallons). initially and 3.1 metric tons (ca. 940
gallons) subsequent to 1983.

Effluent limitations are also aiven for oily storm water
CP
runoff and ballast water treated at a refinery. They would
allow an average discharge.of not more than 8 ppm oil and
grease in the effluent and 1.6 ppm after 1983.

Effluent limitations guidelines for several other industrial
categories also set standards for "oil and grease" discharges,
e. 'a. those for the fertilizer., ferrous and nonferrous metalsP
ferroalloy, meat, seafood and rubber industries. These are
also based on emission rates per unit of production and the
units of production vary widely, making the standards diffi-
cult. to translate into environmentally meaningful terms.
Also the chemical nature of the "oil and grease" (i.e.
hexane extractable materials) emitted varies tremendously,
de-oending on the industry. By way of comparison though, 4(
C,
new source standard mass emission rates of oil and grease

Discharge includes process wastewater, cooling water,
stormwater runoff and ballast water.

Appendix 15
368

would only.be 3.1 kg/day from an average (100,000 tons/year)
amnionia plant. These should be compared with the 41.3 kg/day
from.the hypothetical 100,000 barrel/day oil refinery con-
sidered above.

OIL IN CHESAPEAKE BAY

-A'-e Chesapeake Bay has thus far been spared from large catas-
trophic oil spills of the type that has gained notoriety in
'.recent years. However,, several small biologically damaging
spills have occurred. The United States Coast Guard main-
tains oil spill statistics for the Bay area based on field
observations and investigations. These records show that
the amount of oil spilled annually in the Bay has been
typically 60,000 to 100,000 gallons, or on the average 300
metric tons/year. Oil spills are most frequent in Hampton
Roads and Norfolk port areas, in the lower York-River, and
in the Baltimore Harbor area.

More difficult to estimate are the chronic CLIscharges of oil
into the Chesapeake Bay. The potential sources of discharae
are many, including municipal sewage industrial wastes, ship
generated wastes, commercial and pleasure boats, urban runoff
and river.input.

" T
1'iunicipal Sewage

No data exist on the oil and grease content of sewage dis-
charaed into the Bay. Oil and grease content of Hyperion
Outfall effluents (one-third of which receive secondary
treatment) discharged into the Pacific Ocean off Los Angeles
averaged 19 mg/1 oil and grease (18). Effluents from other
outfalls in Southern California generally had higher oil and
grease concentrations -- up to 70 mg/l. Oil and grease from
municipal sewage has been estimated to be one-half composed
of petroleum oils (15). Thus,- a realistic estimate for the
typical concentration of petroleum oil in sewage is 10 mg/l.
The discharge-of municipal sewage into the tidal waters of
the Chesapeake Bay system is estimated to be roughly 900
mill4on gallons per day (mgd) (20), thus the discharge of
oil from this source would be 36 metric tons/day or just
over 13,000 metric tons/year or approximately 3 million
gallons/year.

Industrial Wastes

Available data on effluent emissions and concentrations for
industrial discharges are generally confined to those re-
ported on permit applications filed with the Corps of
hn,7ineers. They are usually based on the analysis by the
industry of a very few samples and thus are notoriously
'liable. Nonothele-ss it is possible to use these data
unrc@
to lloosely approximate emission rates.

Appendix 15
369

TABLE 15-28
MASS EMISSION OF "OIL AND MMUM" INTO TIDAL
WATERS OF SOUTHEASTERN VIRGINIA (17)

Mass Emission Rate
lbs/day

T
James River Basin
James 71-ver
Fall Line to Appomattox Riv. 57
Appomattox Riv. to Chickahominy Riv. 19 736
Chickaho,miny Riv. to Pagan Riv.
Pagan Riv. to Nansemond Riv. 61
Nansemond Riv. to Elizabeth Riv. (0.02)
Elizabeth River to Mouth (0.26)

Appomattox River
Chickahominy River. 24
Pagan River (0.24)
Nansemond River 74
Elizabeth River 298

Total James River Basin 200294
(below Fall Line)

York River Basin (below Fall Line) 707

Chesap'eake Bay Basin 8
(south of York River Mouth)

Total 211013

Appendix 15-
370

Mass emission rates from industrial sources have Leen compiled
19@ Based
for the southeastern Virginia area (17) (Table 15'@ _"
on these data the mass emission rate for this are--a is 3,500
metric tons/year of oil and grease. Assuming that southeast-
ern Virginia accounts for no more than half of all the indus-
trial emissions to the Bay and again making the admittedly
C.
,unsubstantiated assumption that one-half of this is petroleum
oil., the annual mass emission rate of oil into the Chesapeake
Bay from industrial sources would be at least 3,500 metric
tons (roughly 0-.8 million gallons) or about one-fourth of
the amount from municipal sewage.

J.- Shipping

Waste oil generated by commercial ships may be contained in
bilge or ballast water, the release of which is prohibited
in navigable waters if a visible sheen would be formed.
Thus, technically, very.little oil should be willfully
discharged into'the Bay by the more than 9,000 commercial
vessels which annually call on Chesapeake Bay ports (21).
Illegal or accidental discharges do occur, but it is impossi-
ble-to accurately estimate the magnitude of these emissions.
But it seems improbable that this addition would amount to
more than 1002000 gallons or roughly 400 metric tons would
be discharged from commercial ships.

Federal reaulations regarding the discharge of oil in con-
0 01
tiguous zones, new international agreements on the discharge
of oil from'ships on the high seas, and the possibility of
the extention of territorial seas, all comb *ine to make the
shore based treatment of ship borne oily wastes more desir-
able or necessary. The volume of oily wastes which must be
discharged at Hampton Roads if ships are prohibited from
discharging at sea is estimated to be 102 million gallons
by 1975 (22). This waste contains approximately 2% oil
(i.e. over 2 million gallons), however if this waste is
treated onshore and the resulting discharge is <10 ppm
oil., a mass emission of only about 3 metric tons/year
,(ca. 1000 gallons) results. Thus, although the release
of treated or untreated ship-generated oily wastes may
yet have adverse local environmental effects, in terms
of mass emission to the Bay this source would be minor.

Boats

,01 The input of petroleum into the Bay from small vessels is
similarly difficult to account. In fact, the great vari-
ations in vessel size, engine type, fuel consumption and
operation time makes impossible anything but a crude,
educated.guess.

Appendix 15
37.1.

The total number of registered vessels in the portions of
Maryland, Virginia and the District of Columbia adjacent
to the Chesapeake Bay and its tidal tributaries is over
160POOO (21). Outboard engines discharge 8-10% of their
fuel consumption through the cooling water-exhaust system
(23). Boats with inboard engines lose a considerably
smaller portion of their fuel to the water body. None-
theless, a per boat average of 5 gallons of petroleum lost
per year is probably of the right order. Thus the annual
emission of petroleum from boats is estimated at 800,000
gallons or 3000 metric tons.

Urban Runoff

The National Academy of Sciences (19) estimated an annual
contribution of 0.1 million metric tons (ca. 27 million
gallons) of oil to the world's oceans from urban runoff.
Runoff from suburban Long Island contained from 10 to as
much as 60 ppm of oil and grease, a substantial proportion
of which would be petroleum oil. Comparable data are not
available for Chesapeake Bay urban areas, and extrapolation
is difficult because of lack of information on the volume
of urban runoff. However, if contaminated runoff were 10%
of the total annual rainfall within the 470 square miles
encompassed by Washington, Baltimore, Richmond, Norfolk and
Newport News/Hampton, and if the concentration of petroleum
oil in this runoff were 10 ppm, then over 300,000 gallons
or approximately 1000 metric tons annually enters from run-
off. This hypothetical figure appears a realistic propor-
tion (i.e. one percent) of the NAS global estimate.

River_.Inputs

Estimating the input of petroleum hydrocarbons from-the
rivers draining into the Bay is again made difficult by the
lack of data. NAS (19) estimated the global input from
rivers to be 1.6 million metric tons per year. Based on
their estimate of a concentration of 0.3 mg/1 of petroleum'
hydrocarbons for the Mississippi River and a freshwater
discharge of 6 x 1010 m3/year to the Chesapeake Basin, the
annual addition of petroleum from river runoff is estimated
to be 18,000 metric tons. The NAS report suggested much of
this would be adsorbed to sediment particles.

Summary of Inputs
A balanceIsheet of these crude approximations of inputs of
petroleum to the Chesapeake Bay is given in Table 15_@9-

The overwhelming percentage of total input attributable to
chronic, low-level inputs of petroleum from sewage, industry
and upstream sources is striking. In most minds, oil pol-
lution in the coastal environment is thought of mainly, if.

Appendix 15

TABLE 15-29
SUMMARY OF ESTIMATED ANNUAL INPUTS OF PETROLEUM TO CHESAPEAKE BAY

Source Estimated Annual Input Percentage of Total
(metric tons 1.1 short tons)

Oil Spills 300 0.8%

Municipal Sewage 13SO00 34.9%

Industrial Sources 319500 9.4

Ship Generated Wastes 4010 1.1%

Boats 3.,000 8.1%

Urban Runoff 1$000 2.7%

River Inputs 16.9000 43.0%

Total 37.9200

not exclusively, in terms of marine transportation related
sources. The subject usually brings to mind tanker or ter-
minal spills. This exercise in estimating a mass emission
budget does not suggest that these accidental losses are
unimportant, because they have resulted in documented bio-
logical damage in the Bay, but emphasizes the magnitude and,
thus, potential seriousness of non-accidental chronic inputs.

To be sure, the petroleum inputs from sewage, industry and
runoff come in very small, albeit continuous, doses. The
effective concentrations in the environment would therefore
be expected to be less than in the case of an oil spill.
Disperson of these low concentrations and biodegradation
of the petroleum may be expected to further lessen the
chance of toxic buildup of petroleum. However, petroleum
hydrocarbons may persist in theenvironment for very long
periods of time (some compounds longer than others) and
may have a tendancy to be taken,up and concentrated in
bottom sediments and in organisms (24). Thus the low
levels emitted from the source may allow buildup of toxic
concentrations of petroleum hydrocarbons.

The sources of oil pollution are not spread round the Bay
but are concentrated primarily on the James River estuary
(Hampton Roads and the Richmond-Hopewell area) and in the
Baltimore area. Of course these are sites of input of many
other pollutants as well and the synergistic effects of the
petroleum with other pollutants must be considered. Oil
spills are most frequent in the lower York River, the Hampton
Roads area, and the Baltimore Harbor area. Largest inputs,
of municipal sewage (Fig-15-30) and greatest urban runoff are
at Baltimore, Washington,-Tiampton Roads and Richmond. Indus-
trial sources of petroleum hydrocarbon center at Hopewell,
Yorktown, the Elizabeth River and Baltimore Harbor. Some
ship generated wastes are released in Hampton Roads and
Baltimore harbors and along shipping lanes. Oil pollution
from motor boats may be especially intense in the vicinity
of the many marinas in the Bay area, which are often located
in poorly flushed creeks. The input of petroleum from the
Susquehanna and James rivers must be greater than that from
other rivers entering the Bay, since they have high flow
rates and drain more urbanized or industrialized areas.
Much of this petroleum must be degraded or deposited in
the uppermost Bay.and the upper tidal James where much
of the suspended sediment load is deposited.
Ak
Oil in the Bay Environment

One may ask, in light of these seemingly substantial chronic
inputs of oil to the Chesapeake Bay, what level of contami-
nation exists in Bay environments? Here again, assessment
of the problem is hampered by lack of data. No data exist
for concentrations of petroleum hydrocarbons in water or in

Appendix 15
374

-A R
LOCATION OF MAJOR (>5mgd) A 360
SEWAGE TREATMENT PLANTS

SCALE IN MILES
0- 5 10 ISO

Is -**60
8.5 10.

5.7
296
0.7 .0
015

16.5"'
8"1NP1:0 41

6.8!
6.6' f
653.A
459 38'!
C I I I

9.0

9.6

\0.3
3.9
10 4, I'S *@,D 113

2.8
195

ra.

Note: Numbers are discharge rates in million gallons per day.
4,
Larger numbers are cumulative sums of inputs into the
Bay. (After 20).

FIGURE 15-30: MAJOR MUNICIPAL SEWAGE DISCHARGES IN CHESAPEAKE BAY
Appendix 15
375

fish, shellfish or other organisms. Some data do exist for
"oil and grease" concentrations in sediments. Sediment
samples taken in Baltimore Harbor by EPA's Annapolis Field
Office (25) ranged from 420 to as much as 81,220 mg/kg oil
and grease. Many samples from the inner harbor had concen-
trations in excess of 10,000 mg/kg (i.e. 1% by weight). In
contrast sediments in the vicinity of Tangier Island con-
tained only from 140 to 460 ppm oil and grease. Sediments
collected from the York River Entrance Channel ranged from
30 to 1210 mg/kg, with most with less than 700 mg/kg (26).

"Oil and grease" content represents naturally occurring
lipids and hydrocarbons as well as petroleum hydrocarbons,
thus it is impossible to determine what portion of the "oil
and grease" concentration is petroleum. Also the natural
hydrocarbon-lipid content of bottom sediments and their
ability to concentrate petroleum depend on the grain size
of the sediments and the sedimentation rate. All things
considered, it appears that any "oil and grease" concentra-
tion above 1000 to 1500 mg/kg almost certainly represents
contamination with petroleum. The EPA criterion for over-
board disposal of dredged material of 1500 mg/kg (9) and
the EPA water quality criterion (5) of 1000 mg/kg in fresh-
water sediments thus do not appear unreasonably strict.

ENVIRONMENTAL EFFECTS

In the only study of the effects of oil on Chesapeake Bay
organisms, Bender., Hyland and Duncan (27) described the
effects of a small oil spill on intertidal communities in
the lower York River. The species richness of the inter-
tidal benthos was substantially reduced where the oil
reached shore, compared to adjacent control sites. Fur-
thermoret recovery in terms of both species richness and
similarity of the fauna to control sites was not shown
until two years after the spill. Aqueous extracts of
Bunker C fuel oil, similar to that spilled, proved most
toxic to two of the crustaceans (Gammarus mucronatus and
Pagurus longicarpus) and one polychaete worm (Spio-cNae-
topterus oculatus) tested.

,Oil Spills
The extensive literature on.the environmental effects of
oil spills has been summarized in several reviews (24, 28,
29), thus a detailed rev'iew will' not be attempted here. Al
In summary though, oil can kill marine life directly
through: (1) coatingand asphyxiation, (2) poisoning -
through direct contact or ingestion, (3) exposure to
water-soluble toxic petroleum components, (4) destruction 41
of juvenile forms, and (S) disruption of body insulation
of warm blooded animals. Furthermore, oil may have harm-
ful indirect effects, including: (1) destruction of food

Appendix 15
.376

sources, (2) synergistic effects that reduce resistance to
other stresses., (3) incorporation of carcinogenic and poten-
tially mutagenic chemicals, (4) reduction of reproductive
success) and (S) disruption of chemical clues essential to
survival, reproduction or feeding.

The actual observed effects of oil spills have varied tremen-
dously, though, and many spills have been reported to do
little damage. The severity of an oil spill is dependent
on: (1) the dosage of oil an environment receives 31 (2) the
physical and chemical nature of the oil spilled, including
the effects of weathering, (3) the location of the spill,
(4) the time of year of the spill, (5) the prevailing weather
conditions, and (6) the techniques used to clean up the spill
(30). Biological recovery from the effects of oil spills may
be quite rapid or may extend to more than a decade after the
initial accident (19) depending on the community in question
and whether oil persists in the environment, particularly in
sediments.

Chronic Pollution

Surprisingly, very little research has been conducted on the
effects of chronic inputs of petroleum on coastal and estu-
arine communities. Much of the information available has
been reviewed by the National Academy of Sciences (19),
Copeland and Steed (31) and Baker (32).

Refinery effluents may have considerable impact on benthic
life in confined bodies of water where dispersion of the
effluent is not rapid (32).- For example, animals inhabiting
sediments in Los Angeles Harbor that received large quanti-
ties of oil industry wastes were eliminated or limited to a
single tolerant polychaete (33). The greatest effects were
apparently due to the depletion of oxygen on the bottom by
oxygen-demanding wastes that concentrated in the sediments.
AlsoA saltmarsh plants were killed by a refinery effluent
released in sheltered tidal creeks at Southampton, England
(34). On the other hand, effluents released in more exposed
waters with rapid dispersion seem to have considerably fewer
biological effects (32).

Studies on phytoplankton (35) and zooplankton (36) of Gal-
veston Bay, Texas, indicate decreased species diversity in
the area near the Houston Ship Channel, which is heavily
burdened with petrochemical as well as other toxic wastes.
The effects of lowered salinity and other toxicants compound
the picture, however, and the field evidence that chronic
oil pollution affects planktonic communities is not complete.
However, the more refined experiments of Gordon and ProLse
(37) indicate photosynthesis in chronically polluted coastal
waters may be affected.

Appendix 15
377

Swimming animals may vacate an unfavorable area and thus
avoid harm. Hence, fish may be absent or less diverse
around refinery outfalls or bleedwater discharges (38).
This may effectively reduce fishery productivity in certain
local areas (39).

Among the shallow water ecosystems of the Texas coast, those
receiving oily wastes are characterized by lowered species
diversity, large diurnal fluctuations in dissolved oxygen
concentration, and sometimes near-anaerobic reducing con-
ditions at the bottom (31). Community metabolism -- the
combined amount and relationship of photosynthesis and
respiration of the whole community -- fluctuates wildly.
Under some conditions, both photosynthesis and respiration
are depressed by highly toxic materials; under others,
metabolism is stimulated due to the decomposition of
waste products and release of nutrients.

The effects of oil inputs from such land-based sources as
domestic and industrial wastes and urban runoff have received
even less attention. Farrington and Quinn (40) traced the
cause of high concentrations of petroleum hydrocarbons in
sediments and clams in Narragansett Bay, Rhode Island to
domestic sewage effluents. Hard clams from contaminated
sediments there showed signs of physiological stress and
abnormal growth (41). Pfitzenmeyer (42) found the benthic.
communities in Baltimore Harbor especially depauperate in
black, petroleum-smelling muds, but of course the addition
of a wide range of pollutants there complicates the delim-
iting of causitive factors.

EVALUATION

Adequacy of Standards and Criteria

The legislation and regulations pertaining to oil spills are
certainly adequate for the protection of life in the Bay, in
that they virtually prohibit any spilling of oil. The im-
provements of safety regulations., surveillance and tracing
of spilled oil, control and enforcement would probably reduce
the frequency, magnitude and impact of oil spills in the Bay.
However, it is impossible to completely eliminate the risk
of oil spills. If tanker traffic substantially increases
in the.Bay, maritime traffic control schemes and other
safety precautions should be established to prevent the
chance of collision.

On the other handt the regulations, standards and criteria
pertaining to chronic discharges of petroleum do not seem
adequate. The inputs of petroleum from three major sources,
domestic sewage, boats and urban runoff are largely unreg-
ulated. For those sources for which discharge'standards
apply, the standards are put only in terms of total hexane

Appendix 15
378

extractable "oil and grease", while it may be trace pollu-
tants not easily treatable by conventional means which may
be environmentally harmful. For example, although the
biological treatment of oils in waste water set forth in
the refinery industry effluent limitations guidelines may
be effective in reducing total "oil and grease" concen-
tration, petroleum hydrocarbons less susceptible to
biodegradation, such as the more toxic aromatics and
naphthalenes, may escape treatment. Unfortunately, very
little is known of the hydrocarbon constituents of treated
wastes from refineries and other industrial sources, and
they probably vary widely.

Our uncomfortable ignorance about the effects of chronic
petroleum pollution does not allow a realistic appraisal
of the effects of inputs from chronic sources on Pay
ecosystems. The high levels of oil in sediments in
Baltimore Harbor and probably in the Hampton Roads area
nonetheless provide cause for concern. Furthermore,
the real probability of greatly expanded development
of an onshore petroleum industry in the Chesapeake Bay
area, which may attend recovery of oil under the outer
continental shelf off Delmarva or deep water port devel-
opment, poses a threat of unknown proportions for the
Bay. Clearoly, more information on petroleum pollutants
and their effects is required in order to set standards
and guidelines adequate for the protection of the
environment.

RESEARCH RECOMMENDATIONS

1) Characterization of the chronic petroleum inputs
to the Bay is required.

2) The fate, including processes of degradation and
concentration of oil in the Bay environment needs inves-
tigati.on.

3) Research on the effects of acute and, particularly,
chronic inputs of petroleum on Chesapeake Bay communities
is needed.

4) Sublethal effects of low concentrations of petrol-
eum hydrocarbons on aquatic organisms should be studied.
Particularly worrisome are the possible effects of petrol-
eum hydrocarbons on the detection of chemical clues by
migrating estuarine organisms.

5) Finally, research on the character, fate and
effects of chronic additions of petroleum should be coupled
with research on effective treatment technologies.

Appendix 15
379

REVIEW OF STANDARDS AND CRITERIA RELATED TO CHLORINE

Chlorine is used in many industrial processes but its main
uses which are of greatest importance to water pollution are
(1) as a disinfectant of waste waters for the protection of
public health and (2) for antifouling in water intakes and
cooling water systems, particularly by power plants.

Chlorine is a powerful oxidizing agent and its high toxicity
is the -reason for its use as a biocide.. It is highly soluble
in water, where it may be present as 'free available chlorine
in the form of hypochlorous acid or hypochlorite ion. How-
ever free chlorine degrades rather rapidly, especially in the
presence of light, to chlorides,.major and harmless constit-
uents of marine and brackish wat ers. Chlorine may react with
other compounds in solution, however, and the end product may
be much more stable than free chlorine. Especially in waste
waters, chlorine may react with ammonia to form chloramines
which are slightly less toxic than free chlorine but decom-
pose much more slowly. The sum of free chlorine,inorganic
chloramines and some organochloramines is referred to as
available chlorine.

STANDARDS AND CRITERIA

Neither Maryland nor Virginia have water quality standards
for maximum levels of chlorine permissible in natural waters.
On the other hand., states often have regulations concerning
the minimum levels of residual available chlorine in waste
waters. For example, Virginia requires a residual chlorine
level of 1.0 mg/l for sewage effluent leaving contact tanks
and 2.0 mg/l for facilities discharging into shellfish waters.

The Environmental Protection Agency's Water Quality Criteria
(5) suggest that 0.003 mg/l of residual chlorine be the
maximum for chronic exposure and 0.05 mg/l for short term
exposure for freshwater aquatic life and that an application
factor of 0.1 applied to the 96 hour LCgo should be the cri-
terion for marine and estuarine waters ut that concentra-
tions in excess of 0.01 mg/l are unacceptable. The document
hastens to add, however,, that as more knowledge of toxicity
of chlorine to marine organisms becomes available the cri-
terion should probably be equivalent to that set for fresh
water.

The proposed Effluent Limitations Guidelines for the steam
electric power generating industrial category includes stand-
ards for the discharge of chlorine (43). Under these pro-
posed regulations, free available chlorine concentration
must not exceed an average of 0.2 mg/l nor a maximum of 0.5

Appendix 15
380

mg/l during one two hour period per day under the Best Prac-
ticable Control Technology Currently Available by 1977.
Furthermore, no discharge of available chlorine would be
allowed under the Best Available Treatment Economically
Achievable, the 1983 limitations. Currently, it is common
practice in the operation of power plants to chlorinate to
a 0.5 to 1.0 mg/l residual chlorine level for 30 minutes to
an hour several times a day or to continuously maintain a
residual level of 0.5 mg/l.

There are stipulations both in the proposed effluent limi-
tations and in the Federal Water Pollution Control Act
(PL 92-500) for variances from these rigid standards. The
proposed limitations allow, at the discretion of EPA, for
higher levels of chlorination and/or longer dosing periods
if required to maintain necessary cleanliness in the cooling
water system. Section 316 (a) of the Act further allows
exemption of electric power generating plants from the
effluent limitations if it can be shown that no environ-
mental harm is resulting from its operation.

It is significant to note that no effluent standards for
chlorine have yet been proposed for sewage treatment plants.
.In fact the standards for secondary treatment set by EPA for
maximum concentration of fecal coliform bacteria of 200/100
nil require substantial disinfection. In this country chlo-
rine is almost exclusively used as the disinfectant. It is
not known at this time whether future sewage effluent stand-
ards required by the Federal Water Pollution Control Act will
stipulate effluent standards for chlorine.

CHLORINE AND THE CHESAPEAKE BAY

Al,though known as a water pollution problem in fresh waters
for some time (45), chlorine was not suspected of being
harmful to Chesapeake Bay organisms until recently. The
researchers at the Natural Resources Institute of the
University of Maryland showed that chlorination of cooling
water at the Chalk Point power station reduced primary
productivity of the phytoplankton passing through by as
much as 91%., resulting in as much as a 6.6% maximum loss
in primary production in the adjacent tidal segment of the
Patuxent River (46). Heavy mortalities in zooplanktonic
copepods passing through the plants cooling water system
were likewise attributed to chlorination (47). Experiments
done with populations of the important zooplanktonic cope-
pod Acartia tonsa from the York River showed that residual
chlo-f-ineconcentrations of 0.75 mg/l similar to those
employed at the Yorktown power station were likewise
lethal (48).

Appendix 15
381

Although previously shown by Tsai (49) to be the cause of
serious effects on fish communities in freshwater streams
in the Chesapeake Bay drainage basin, chlorination of sewage
CP
had not been known to have deleterious environmental effects
in the tidal waters of Chesapeake Bay until it was implicated
as the,cause of large fish kills in the James River during
the spring and summer of 1973 (50). An investigation led
by the Virginia State Water Control Board concluded, after
extensive field surveys and bioassays in the field and lab-
oratory, that the cause of the mortality of over one half
million fish was residual chlorine from the James River and
Small Boat Harbor sewage treatment plants of the Hampton
Roads Sanitation District. It was shown that the processed
waste water was routinely overchlorinated largely because of
inadequate application of analytical techniques. In fact,
probably one of the most common causes of environmental prob-
lems with chlorinated discharges is gross overchlorination
(45). Reduction in the level of chlorination resulted in
immediate alleviation of the fish mortality, but necessitated
temporary closure of shellfish grounds.

M
71
easurements of residual chlorine in the vicinity of the
sewage outfalls during the period of the fish kill yielded
concentrations of 0.2 to 0.7 mg/l at the James River treat-
ment plant (at the mouth of the Warwick River) and.1.0 - 2.2
mg/l at the Small Boat Harbor plant (at Newport News Point).
Subsequent monitoring (51, 52) of available chlorine concen-
trations in the James River has found concentrations often
greater than 0.5 mg/l in the vicinity of sewage outfalls and
concentrations of up to 0.4 mg/l, but usually less than 0.1
mg/l at locations quite far removed from outfalls (Fig. 15-31).

Currently, the Virginia State Water Control Board at the
request of the Virginia Marine Resources Commission has
ordered a reduction in the level of chlorination during
the season of larval recruitment to the important James
River seed oyster grounds. However, because of plans to
greatly enlarge the capacity of the James River plant,
necessitated by a burgeoning population and extension of
service, periodic reductions of chlorination can be, at
best, only a temporary solution.

The James River fish kill suggests that deleterious effects--
though not necessarily of equivalent magnitude,--may be
realized in other segments of the Bay receiving chlorinated
sewage effluents. Nearly one billion gallons of sewage is
discharged into the tidal waters of the Chesapeake Bay sys-
tem every day (20). Most of this is chlorinated to varying
degrees.- The distribution of these inputs (Fig.15-30) sug-
gests that the areas where the potential of deleterious
effects of waste water chlorine is most serious are the
Baltimore Harbor-Back River area, the upper tidal Potomac
River, the lower James River-Hampton Roads-Elizabeth River

Appendix 15
382

0.01-
.440 WILLIAMSBURG STP

370 0
07 0.02
0.
14

0.0
0.2
JAMES RIVER STP
0.03

.37

0 1-
.0-09

0.05-
370
0.27

0.02-
0.07 SMALL
BOAT HARBOR
STP

JA IVES R/ VER

760140' -76013d

Note: Values are ranges of monthly measurements taken in spring,
@P

1974 by Adams (51). Circled values were measured by Huggett (52).
FIGURE 15-31: RESIDUAL CHLORINE IN THE LOWER JAMES FSTITARY Appendix 15
383

area and the upper tidal James River. However, this does
not preclude the possibility of deleterious effects result-
ing from small sewage treatment plants, particularly if they
discharge into small or confined bodies of water.

ENVIRONMENTAL EFFECTS OF CHLORINE

Several timely reviews of the effects of chlorine on
aquatic life have recently been published (45, 53, 54)
so no attempt will be made to provide a complete review.
Most of the available information pertains to freshwater
organisms and it indicates that aquatic organisms vary
widely in their tolerance of chlorine. Generally short
term exposure (several minutes to several hours) to con-
centrations of residual chlorine of 0.2 mg/l is lethal
or otherwise harmful to many freshwater fishes and brown
trout are killed after only 2 minutes exposure to 0.04
mg/l. Longer exposure to concentrations of 0.1 to 0.2
mg/l is lethal to most species tested and some crus-
taceans may be killed by concentrations of less than
0.01 mg1l.

Few data exist on the chlorine toxicity levels for marine
and estuarine species. However, it appears that LC50's
for several fishes and invertebrates common to Chesapeake
Bay are in the neighborhood of 0.2 to 0.1 mg/l, i.e.,
similar to those for all but the most sensitive freshwater
species. On this basis and considering the application
factor of 0.1 recommended in the Water Quality Criteria
residual chlorine concentrations greater than 0.01 mg/l
are potential harmful. Concentrations exceeding this
level are routinely encountered in the lower James River.

Free chlorine degrades rapidly in the environment but the
combined forms, chloramines and chlorinated organic com-
pounds, are much longer lived. Given the high concen-
tration of ammonia and reactive organic compounds in
treated sewage, it is unlikely that much of the residual
chlorine discharged would be in the form of free chlorine.
Little is known of the residence time of chloramines and
organochlorides in the estuarine environment.

'Appendix 15
384

.EVALUATION

The seriousness of the problem suggests that states
should adopt water quality standards for residual
chlorine. For these the EPA proposed criteria appear
reasonable. However, analytical problems (45) would
make monitoring and enforcement difficult.

Because the major source of residual chlorine is public
treatment facilities, they cannot simply be turned off
if water quality standards are exceeded. The societal
conflicts between the need for economical waste dis-
posal, public health requirements and environmental
considerations do not meet with easy solutions. From
the environmental perspective, however, it seems imper-
ative to test and implement alternate disinfection tech-
nology in order to eliminate or reduce the input of
toxic chlorine into aquatic ecosystems. Alternatives
include disinfection with ozone and ultraviolet light (51).
Both of these have drawbacks. Ozone is expensive and
ultraviolet light is ineffective with turbid effluent.
More practical seems to be dechlorination of chlorinated
wastes by reaction with sulfur dioxide, sodium bisulfite,
sodium thiosulfate or activated carbon (53). Investiga-
-tions conducted on dechl6rinated effluents in the San
Francisco Bay area (55) indicate that cechlorination by
addition of sodium bisulfite consistently removed all
chlorine-induced toxicity in both primary and secondary
sewage effluents. Furthermore, Dean (53) estimated that
disinfection with chlorine followed by dechlorination
should cost not more than 1.3 times the cost of disin-
fection alone.

Finally, it is obvious that research is urgently needed
on the effects of residual chlorine on estuarine species
and communities, the fate and persistence of combined
chlorine in the Chesapeake Bay, and analytical methods
for the routine analysis of chlorine in estuarine waters.

Appendix 15
385

CONCLUSIONS

Recently promulgated regulations and others in the process
of development--most of whichwere provided for by the
Federal Water Pollution Control Act of 1972--will result
in substantial changes in water quality standards and in
the patterns of input of pollutants into the Nation's
waters. In the immdeidte future, industrial discharges
will be most directly affected as effluent limitations
are applied and the National Pollution Discharge Elimi-
nation System is more fully developed. More difficult
to predict is the success of reducing or eliminating
pollutant discharges from publicly owned sewage treatment
plants and from non-point sources.

To accurately assess the impact of compliance with these
standards and regulations on Chesapeake Bay ecosystems is
a virtually impossible task. In part this is due to a
lack of knowledge about the fate of pollutants introduced
into the Bay. Thus, our ability to predict environmental
concentrations which would result after elimination of
point sources is limited. More basically, though, there
is an embarrassing ignorance of the present effects of
pollutants on Bay ecosystems. This lack of knowledge of
the state of health of the Bay makes difficult any prog@-
nosis for improvement or recovery. Perhaps the forth-
coming National Commission on Water Quality studies on
the environmental impact of the Federal Water Pollution
Control Act will shed some light, but it seems, for the
time being at least, that discharge elimination goals
will be pursued with little or no quantitative knowledge
of the environmental effects of these actions.

Appendix 15
386

1. McKee, J. E. and H. W. Wolf (Editors). 1963. Water
Quality Criteria. 2nd ed. California State Water
Quality Control Board Publication 3-A. 548 p.

2. Federal Water Pollution Control Administration. 1968.
Water Quality Criteria. U. S. Government Printing
Office, Washington, D. C. 234 p.

3. Warren, C. E. 1971. Biology and Water Pollution
Control. Saunders., Philadelphia. 434 p.

4. National Academy of Sciences/National Academy of
Engineering. 1973. Water Quality Criteria, 1972
(in press).

S. Environmental Protection Agency. 1973. Proposed Water
Quality Criteria. Volume I. U. S. Government Printing
Office, Washington, D. C. 425 p.

6. Environmental Protection Agency. 1973. Comparison of
NTAC, NAS, and Proposed EPA Numerical Criteria for Water
Quality. Environmental Protection Agency, Washington,
D. C.

7. Environmental Protection Agency. .1974. Thermal Dis-
charges Proposed Procedures.for the Imposition of
Alternate Effluent Limitations, 39 Federal Register
11434, March 28, 1974.

8. Environmental Protecti on Agency. 1973. Proposed
Environmental Protection Agency Regulations on Toxic
Pollutant Standards, 38 Federal Register 35388.

Environmental Protection Agency. 1973. Environmental
Protection Agency Criteria for Evaluation of Permit
Applications for Ocean Dumping. 40 Code of Federal
Regulations, Part 227.

10. State of Maryland, Department of Water Resources. 1973.
Water Pollution Control Regulations (08.05.04.01-08.05.
04.11).

11. Federal Water Pollution Control Act Amendments of 1972,
PL 92-500. Sec. 311(b).

12. Environmental Protection Agency. 1973. Regulations on
Oil Pollution Prevention. 40 Code of Federal Regula-
tions., Part 112 (38 FR 34164, December 11, 1973).

AT)T3endix 15
387

13. Council on Environmental Quality. 1973. National Oil
-and Hazardous Substances Pollution Contingency Plan.
40 Code of Federal Regulations, Part 1510 (38 FR 21888,
August 13, 1973).

14. Environmental Protection Agency. 1971. Regulations on
Discharge of Oil. 40 Code of Federal Regulations, Part
110 (36 FR 22487, November 25, 1971).

15. Environmental Protection Agency. 1974. Effluent Limi-
tations Guidelines and New Source Standards for the
Petroleum Refining Point Source Category. 40 Code of
Federal Regulations, Part 419.

16. Roy F. Weston, Inc. 1973. Draft Development Document
for Effluent Limitations Guidelines and Standards of
Performance., Petroleum Refining Industry. Environmental
Protection Agency, Washington, D. C.

17. Commonwealth of Virginia Water Control Board. 1973.
James River Comprehensive Water Quality Management
Study. Vol. VII - 8 & 9. Existing Data Base for
Industrial Wastewater Management Systems.

18. Southern-California Coastal Water Research Project.
1973. The Ecology of the Southern California Bight:
Implications for Water Quality Management. Southern
California Coastal Water Research Project, El Segundo,
Calif. 531 p.

19. NationalAcademy of Sciences. 1974. Petroleum in the
Marine Environment. (Draft report). 405 p.

20. Brushl L. M.. 1974. Inventory of Sewage Treatment Plants
for Chesapeake Bay. Chesapeake Research Consortium
Publication No. 28. 62 p.

21. Lucy, J. 1974. Unpublished data.

22. F. R. Harris, Inc. 1973. Report on Port Collection and
,Separation Facilities for Oily Wastes. U. S. Department
of CommerceP Maritime Administration, Washington, D. C.

23. Bender, M. E. Personal communication.

24. Boesch, D. F.1 C. H. HershneT and J. H. Milgrim. 1974.
Oil Spills and the Marine Environment. Ballinger,
Cambridge, Mass. 114 p.

2S. Corps of Engineers, Baltimore District. 1973. Chesa-
peake Bay Existing Conditions Report. Appendix B. The
Land-Resources and Usef Vol. II. Corps of Engineers,
Baltimore,, Md.-

ADDendix 15
388

26. Corps of Engineers, Norfolk District. 1972. Review
Report on York and Pamunkey Rivers, Virginia. Corps
of Engineers, Norfolk, Va.

27. Bender., M. E.V J. L. Hyland and T. K. Duncan. 1974.
Effect-of an oil spill on benthic animals in the lower
York River., Virginia, p. 150-153. In Proceedings,
Marine Pollution Monitoring (Petrolj-um) Symposium
and Workshop. National Bureau of Standards, Gaithers-
burg, Maryland.

28. Nelson-Smith, A. 1972. Oil Pollution and Marine
Ecology. Elek Science, London. 260 p.

29. Butler., M. J. A. and F. Berkes. 1972. Biological
Aspects of Oil Pollution in the Marine Environment.
A Review. Marine Sciences Centre, McGill Univ. Man-
uscript Rept. No. 22, 118 p.

30. Straughan, D. 1972. Factors causing environmental
changes after an oil spill. J. Petrol. Tech., March
1972:250-254.

31. Copeland, B. J. and Steed, D. L. 1974. Petrochemical
waste systems, p. 353-370. In: Odum, H. T., Copeland,
B. J., and McMahan, B. A., eU-itors. Coastal Ecological
Systems of the United States, Vol. III. Conservation
Foundation, Washington, D. C.

32. Baker, J. M. 1973. Biological effects of refinery
effluents, p. 71S-724. In: American Petroleum Insti-
tute. Proceedings of a 'Joint conference on prevention
and control of oil spills, Washington, D. C., March
13-15. Washington, American Petroleum Institute.

33. Reish, D. J. 1965. The effect of oil refinery wastes
on benthic marine animals in Los Angeles Harbor,
California, p. 355-361. Sympos 'ium Commission inter-
nationale exploration,scientifique Mer Mediterranee,
Monaco., 1964.

34. Baker,, J. M. 1971. Refinery effluent. In: Cowell,
E. B. (ed.). Proceedings of the symposiuii-on the
ecological effects of oil pollution on littoral com-
munities, London, 30 November - 1 December, 1970.
London, Institute.of.Petroleum.

35. Hohn, M. 1959. The use of diatom populations as a
measure of water quality in selected areas of Galveston
and Chocolate Bay,, Texas. Publ. Inst. Mar. Sci. Univ.
Texas 6:206-212.

Appendix 15
389

36. Odum, H. T.S Cuzon du Rest, R. P... Beyers., R. J. and
Allbaugh, C. 1963. Diurnal metabolism, total phos-
phorus, Ohle anomaly, and zooplankton diversity of
abnormal marine ecosystems of Texas. Publ. Inst. Mar.
Sci. Univ. Texas 9:404-453.

37. Gordon, D. C. and Prouse, N. J. 1973. The effects of
three oils on marine phytoplankton photosynthesis.
Mar. Biol. 22:329-333.

38. Chambers., G. V. and A. K. Spark s. 1959. An ecological
survey of the Houston Ship Channel and adjacent bays.
Publ. Inst. Mar. Sci. Univ. Texas 6:213-250.

39. Spears, R. W. 1971. An evaluation of the effects of
oil, oil field brine, and oil removing compounds, p.
199-216. In American Institute of Mining, Metallurgical
and PetrolTulm Engineers. AIME Environmental Quality
Conference, Washington, D. C., June 7-9, 1971. American
Institute of Mining, Metallurgical, and Petroleum
Engineers.

40. Farrington, J. W. and Quinn, J. G. 1973. Petroleum
hydrocarbons in Narragansett Bay. I. Survey of hydro-
carbons in sediments and clams (Mercenaria mercenaria).
Estuar. Coastal Mar. Sci. 1:71-7"9.

41. Jeffries, H. P. A stress syndrone in the hard clam,
Mercenaria mercenaria. J. Invert. Pathol. 20:242-251.

42. Pfitzenmeyer, H. T. 1971. Benthos, p. 20-49. In A
Biological Study of Baltimore Harbor. Natural RFs-ources
InstituteX Univ. Maryland. Ref. No. 71-76.

43. Environmental Protection Agency. 1974. Effluent Limi-
tations Guidelines and Standards for the Steam Electric
Power Generating Point Source Category. 39 Federal
Register 8294, March 4,-1974.

44. Beauchamp, R. S. A. 1969. The use of chlorine in the
cooling water system of coastal power station. Chesa-
peake Sci. 10:280.

45. Brung s, W. A.- 1973. Effects of residual chlorine on
aquatic life. J. Wat. Pollut. Cont. Fed. 45:2180-2193.

46. Hamilton, D. H.,, Jr., D. A. Flemer, C. W. Keefe and J.
A. Mihursky. 1970. Power plants: Effects of chlorina-
tion on e'stuarine primary production. Science 169:197-
198.

47. Heinle,, D. R. 1969. Temperature and zooplankton.
Chesapeake Sci. 10:186-209.

Appendix 15
390

48. Dressel., D. M. 1971. The effects of thermal shock and
chlorine on the estuarine cQpepod Acartia tonsa. M.S.
Thesis, Univ. Virginia. 58 p.

49. Tsai, C. 1971. Water quality and fish life below
sewage outfalls. Progress Rept., Natural Resources
Institute., University of Maryland.

50. Virginia State Water Control Board. 1974. Fish Kill
73-025, James River. Virginia State Water Control
Board, Richmond.

51. Adams, -D. D. 1974. Comprehensive Investigations and
Monitoring of Hampton Roads Sanitation District Sewage
Outfalls and Receiving Waters - Monthly Reports, April
June, 1974. Old Dominion University Research Found-
ation, Norfolk.

52. Huggett, Re J. 1974. Unpublished data.

53. Dean, Re Be 1974. Toxicity of waste water disinfect-
ants. News of Environmental Research in Cincinnati,
July 5, 1974. U. S. Environmental Protection Agency,
Cincinnati.

54. Becker, C. D. and T. 0. Thatcher. 1973. Toxicity of
Power Plant Chemicals to Aquatic Life. U. S. Atomic
Energy Commission, Washington, D. C.

55. Esvelt, L. A., We J. Kaufman, and Re E. Selleck. 1973.
Toxicity assessment of treated municipal wastewaters.
J. Wat. Pollute Conte Fed. 45:1558-lS72.

Appendix 15
391

CHAPTER VIII

PROBLEM AREAS AND FUTURE REQUIREMENTS

The purpose of this appendix has been to help Chesapeake
Bay decision makers in their understanding and appreciation
of the estuary for which they are responsible. Managers
and mankind in general have historically been preoccupied
with production to the exclusion of all else. It was
not necessary to be concerned about waste products as
long as "progress" benefited. It has only been in the
past few years that a concerned population has started
complaining about the polluted environment. Until now
gas exchange, water purification, nutrient cycling and
other-protective functions of self-maintaining eco-
systems have been taken for granted. Other population
numbers and environmental manipulations were not of the
magnitude that affected regional and global balances.
It was not obvious,.as it is now, that mankind's actions
were detrimental to natural processes. As Odum. (1969)
stated: "the one problem, one solution approach" is
no longer adequate and must be replaced by some form
of ecosystem analysis that considers man as a part,
not apart from the environment."

PROBLEM SETTING

We live in an age of modernity and development, based
to some degree on the extravagent use of America's
resources. In the headlong rush toward newness and
convenience, little concern has been voiced over the

AnDendix 15
393

loss or degradation of biological systems that are
largely invisible and of no direct economic import.
The long-term effects are now being realized, however,
in marked changes in our finite global air and water
system.

A key part of the problem is the existing and institu-
tional arrangements under which only economic consider-
ations manifest themselves. Legislation is difficult
in coming unless direct economic benefit can be demon-
strated, or a crisis arises prompting action. Reaction
to crisis is, of course, an inefficient approach to
resource management. Also, misallocation of resources
results when the producer is allowed.to pass the
unpleasantness, nuisance, or other aggravations of
his operation to his downstream neighbor or the global
ecosystem. Ideally, the costs of environmental damage
would be charged in sum.to@th,e despoilers. A true cost
of goods and services would thus be attained, along with
much simplified and efficient resource management.

Another problem lies in the diffi'culty in quantifying
environmental damage and the side effects resulting from
man!s activities. The cause-and-effect relationship
between a pollutant discharge and an occurrence in the-
environment may be difficult to perceive if it occurs
at a location remote from the point of emission, is
long delayed in appearing, is of low intensity, or if
it is intermingled with a host of other variables. In
addition, even if causal factors can be satisfactorily
shown, it is often difficult to identify the offender
or, if he can be identified, to assess his share of the
effect.

Although problems in the biologic system exist that are
readily observable, such as oil spills, oxygen depletion,
and bacterial blooms, many difficulties among the biota
Are difficult, if not impossible, to perceive due to
knowledge gaps or lack of sufficient monitoring activity.
Problems in other resource categories of shortage, over-
use, or degredation, are more readily ascertained. The
introduction of DDT, for example, hailed at the time as
a godsend to American agriculture, was only found to be
deleterious after many years, and m&nifold complications
and harmful environmental effects had arisen. With
profligate new chemicals, process wastes of largely unknown
effects on the ecology, and introduction of other toxic

Appendix 15
394

substances, such as herbicides and insecticides, an
obvious need can be seen for more research and inves-
tigation. A comprehensive knowledge of the effects
of introduced materials to the estuarine ecosystem,
along with anunderstanding of the interacting vari-
ables in nature, such as current, salinity and temper-
ature, would enable vastly increased predictability of
effects and a sound basis for qualitative management
decisions.

Discussion of environmental and biological quality
problems, specific to Chesapeake Bay, follow in the
next two sections. All references cited are listed at
the end of Chapter VI.

ENVIRONMENTAL QUALITY PROBLEMS

Estuaries have enormous significance for man, both
ecologically and economically. They are areas of
great amounts of primary and secondary productivity.
Cronin and Mansueti (1971) stated, " . . . they are
organic factories, traps for sediments, reservoirs for
nutrients and other chemicals, and the productive and
essential habitat for a large number of invertebrates,
fish, reptiles, birds, and mammals. Annual plant
growth and decay, providing continuous large quantities
or organic detritus, is one of the major components of
the cycling of nutrients in estuaries." McHugh (1967)
reported that the annual harvest of fish, both sport
and commerical, in the Chesapeake Bay amounts to
125 lb/acre with a potential of 600 lb/acre. He also
estimated that nearly two-thirds of the commerical

-Appendix 15
395

catch of fish off the Atlantic coast are estuarine-
dependent (McHugh, 1966). Oysters, clams,and blue
crabs are other important economical resources of the
Bay.

Chesapeake Bay is also important because it serves
as a wintering area for Canada geese, ducks, whistling
swans and many shore birds (Massmann, 1971). It is also
an important recreational area. Its value in terms of
the pleasure derived from sailing, f@shing and swimming
cannot be overestimated.

It must be recognized that "pollution"* was not
invented by man. Society has merely accelerated processes
,that have always occurred in nature (Williamson, 1972).
This acceleration can be observed by the layman in fish
kills, algal blooms, the restriction of municipal beaches
because of microbiological contamination and the decreased
abundance of shellfish resulting in increased cost.

The Chesapeake Bay therefore faces attacks on its
integrity from nature as well as society. Three natural
forces that may affect the Bay deleteriously are wind,
flooding and storm surges. The problems caused by Tropical
Storm AGNES are still being felt around the region. The
tremendous quantity of freshwater dumped into the Bay by
AGNES caused a salinity reduction. Freshwater runoff
carried huge quantities of sediment., debris and untreated
sewage into the estuary. Because of the decreased salinity,
added sedimentation and the heat wave following the storm,
the oxygen concentration was decreased, resulting in benthic
organism mortalities. Swift currents and salinity reduc-
tions displaced larval,, juvenile and adult fish from their
normal feeding, spawning and nursery grounds. Blue crabs
were also redistributed from their normal habitats.

The Research Planning Committee of the Chesapeake
Research Consortium prepared two tables listing the
causes of biological problems in the Chesapeake Bay
and the geographical areas of particular concern for

Wass (1967) defined pollution as an "environmental
alteration detrimental to most indigenous life".

Appendix 15
396

solution of biological pro)Dlems. (Tables 15-30 and 31) William-
son, 1972). The localities of major concern are illus-
trated in Figurel5-32. The committee also recommended
certain areas for additional study in the near future:
(1) nutrient loading (2) addition of hazardous substances
(3) sedimentation (4) effects of engineering activities
(e.g., dredging) (5) extraction of living resources (6)
problems resulting from alterations and destruction of
wetlands and (7) impact of regional population growth and
.de.struction (Williamson, 1972).

Nutrient enrichment of an estuary results mainly
from human waste or its degradation products. This
enrichment often results in artificial or cultural eutroph-
ication*, which may deleteriously affect the ecosystem.
Eutrophication is not always undesirable; it is a form
of pollution only when its effects prevent the use of a
body of water or associated products (Frazier, 1972).
Frazier (1972) listed some of its harmful effects: W
certain species and/or certain groups of organisms may
flourish at the expense of others (e.g.,, algal blooms),
(2) municipal wastes may cause a lowering of the oxygen
content of the water since they often contain much
phosphorus resulting in fish and shellfish kills
(3) clogging power plant iniake structure
with plant growth, (4) reduction of freshwater flow in an
estuary and (5) aesthetic effects - smells of decay.

Cronin (1967) reported that through a tidal cycle
the release plume of a sewage outfall will be transported
both up and downstream., covering the exact discharge site
continuously or a minimum of two times during the cycle
At the site of a sewage outfall macroinvertebrates areg@nerally
absent from the sludge and soft mud. At zones of increas-
ing distance from this site macroinvertebrates will begin
to appear, but many will obviously still be harmfully
affected by the effluent (e.g., the growth of a clam may
be inhibited). At a greater distance, an abundance of
mollusks, worms, diatoms and other species will be present
and eventually normal communities will be formed.

1utrophication is identified as a natural increase in
nutrient supply (Frazier, 1972). Artificial or cultural
eutrophication is enrichment as a result of man's activities
and is usually a greatly accelerated condition compared to
natural conditions.

Appendix 15
397

TABLE 15-30
CAUSES OF BIOLOGICAL PROBLEMS IN CHESAPEAKE BAY
(Williamson, 1972)

MATMAL PRIMARY SOURCES/CAUSES

EMISSIONS AND ADDITIONS TO THE BAY

Nutr-lents Municipal and domestic wastes,
agriculture
Sediments Agriculture, urbanization, road
building
Biocides Agriculture, pest control
Metals Industry, biocides, mining
Petroleum Boats, municipal and suburban runoff
Radionuclides Nuclear power plants
Leachates Land fills
Other Chemicals Industry, power plants
Heat Thermal discharges
Exotic species Introductions, deliberate or
accidental

DELETIONS FRCM THE BAY

Process or products
Freshwater diversion Dams, consumptive use, Chesapeake &
Delaware Canal
Fishery products Exploitation, poor fishing techniques

ALTERATIONS OF WETLANDS, SHOFELINES AND SHALLOWS

Process
Shoreline erosion Natural processes, wetlands
destruction
Hab'itat destruction Dredging, duiTping, filling
Loss of productivity Dredging, dumping, filling
Flooding, sedimentation Dredging., durrping, filling

CUMULATIVE EFTECTS OF MULTIPLE ENGINEERING CHANGES

Process
Erosion Filling Bulkheading
Sedimntation Dredging Piling placement
Habitat destruction Groin construction Construction
Loss@of productivity Spoil deposition

Appendix 15
.p
398

TABLE 15-31
AREAS OF PARTICULAR BIOLOGICAL CONCERN IN CHESAPEAKE BAY
(Williamson, 1972)

Area Reason for concern Immediacy of problems
(if this is reason for concern)

Maryland- Western Shore
Susquehanna River Nutrients, modification of fresh water flow, Freshwater flow-immediate
sediments, energy,fisheries others-chronic
Bush River Proposed thermal addition Near term
Back River Municipal waste, nutrients Immediate
Patapsco River Municipal and industrial wastes, dredging, Chronic
spoil disposal, all hazardous materials
Magothy, Severn and Residential wastes, agricultural runoff Chronic
South Rivers (nutrients), recreation
West and Rhode Rivers Protected area of low stress for baseline
data and experimental study
Calvert Cliffs Thermal addition. radionuclides, political Immediate
problems
Cove Point Proposed liquid natural gas terminal, dredging, Immediate
spoil disposal
Patuxent River Thermal addition, nutrients, area of immediate immediate
stress
Maryland-Eastern Shore
Chesapeake & Modification of freshwater flow, dredging Immediate
Delaware Canal and spoil disposal, shipping, oil spills
Chester River Heavy metals, biocides Long range
Chuptank River Nutrients. sedimentation Near term
Dorchester County Shoreline erosion Chronic
Maryland & Virginia
Upper Tidal Urbanization, municipal wastes (nutrients), Chronic
Potomac River sediments, legal and institutional problems
Lower Tidal Oil spills, dredging, fisheries Near term
Potomac River
Lower eastern Economy, agricultural wastes. wetlands. Immediate
shore fisheries, erosion, access to water, industrial
development
Virginia
Rappahannock Freshwater flow modification, industrial Freshwater flat -immediate:
River wastes, area of relatively low stress, nutrients others-chronic
Upper York Industrial wastes, freshwater flow modification Freshwater now-immediate.
River wetlands, fisheries others-chronic
Lower York Thermal addition, oil transport, dredging, spoil Immediate
River disposal, wetland alteration, fisheries
residential wastes, VIMS

Upper Tidal James River Industrial and municipal wastes. dredging, Immediate
(above Jamestown) heavy metals, human health (bacterial counts)
Lower Tidal James River Industrial and municipal wastes. transportation Immediate and chronic
(below Jamestown) (water and vehicular), spoil disposal, dredging,
thermal addition, fisheries, heavy metals
Hampton Roads Transportation (water & vehicular), ship waste. Immediate and chronic
spoil disposal,recreation
Nansemond, Elizabeth and Heavy metals, municiple wastes, fisheries, Immediate
LaFayette Rivers urbanization, oil handling and transport,
shipping.shoreline modifications
Lynhaven system Residential development. nutrients. shoreline Chronic
modifications
Bay-mouth area Only exit from sytem to sea/sedimentation Near term
fisheries (crab and spawning area)

Appendix
399

SUSQUEHANNA RIVER
Nutrients Modification 61
fr*Ah-w42t0F flow, sediment S468qw henna
fisheries River
3 CHESAPEAKE and DELAWARE
3
6
NACK RIVER CANAL
Municipal waste, C 0 C'"o% Modification of fresh-water
nutrients low, dredging and spoil
d
Isposel. shipping, off splil@

PATUXENT RiviR e
Thermal addition 5
.nutrients

CALVERT CLIFFS AREAS of POLLUTION
1% 1 Sewage wastes
Thermal additle
09 at 2 Dredging Spoil
Poll 3 lnpoundmbnts
4 Therm
as Poilution
3 *P*troiewm Shoros
6 Petrecherniceis

COVE POINT
-.0
Proposed liquid et
naturo gas terminal
I
dredgl:g
1. spoil
I of a 0
*,a.
VOL
jb

RAPPAHANNOCK It IVER
freshwater flow modillcotior%
Industrial wastes, nutrients

YORK RIVER
Industrial waste S.
or
1, fre.hwat
flow m6dification, wetland
lterat:ons,,fisherl LOWER EASTERN SHORE
es
'herma add ions oil
:?rlcultural.wast*s medificatlea
transport. dredging spoil
dispaso -41fland fisherf*s, eresleiri,
residential wastes
M. .-jaclustrial 41104;@Iopmaat

JAMES RIVER
Industrial. and mun4lpal wastes
dredging. JF A;
.spoil disposal
tali, thermal
.heavy me addition fo,#
transportion (water and vehicwlor)
high bacterial count%

2
NANSEMOND, ELIZABETH and LAFAYETTE
RIVERS
10 20 HAMPTON ROADS Heavy metals. muncipal wastes. flahselog,
TrumspOrtation (water and web cuter - vrisonizatlea, oil Itsmilling WW trenspw&
ship waste i spoil dlspesdsl@ nftwe I AMPP10%. Sherell" asedifigatlem

FIGURE 15-32: AREAS OF POLLUTION IN CHESAPEAKE BAY
AD'Dendix 15
Information modified from Odum and Copeland
400 (1974) and Mastrangelo (1972)

Up to the present time the Chesapeake Bay has been able
to withstand nutrient enrichment, but Frazier (1972) believes
that it faces a serious threat to its stability if this
.enrichment is allowed to continue at an accelerated rate.
The solution to the nutrient pollution problem by d@ilution
is obviously limited. However, no alternate solution to
this problem has been ascertained.

Pesticides, heavy metals, fecal pathogens.and radio-
active materials are examples of hazardous additions to
the Chesapeake Bay. They may cause fish kills and/or the
restriction of shellfish consumption.

Little is known about the effects of pesticides.on.
the biota of Chesapeake Bay. Only in a few cases have
mortalities been attributed directly to pesticides. More
than likely,,,any detrimental effects cau/@ed' by,peqticides
in the Bay are,subtle rather than immediate (Munson and
Huggett, 1972). In other words the effects of a particular
contaminaht will not necessarily be noticed until there
is a continuous numerical decrease of organisms (e.g., soft-
shell clams) over a period of time (months or years).
Pesticides have been shown to be highly concentrated by
Chesapeake Bay mollusks (Williamson, 1972), but the present
levels in the Bay do not appear to be crit 'ical. However,
pesticide levels require continuous monitoring in order
to prevent levels great enough to cause mortalities and
food contamination (e.g., blue crabs and sof tshell clams)
(Williamson, 1972).

Examples of heavy metals of immediate concern for
the Chesapeake Bay are mercury, arsenic, cadmium, lead,
chromium and nickel (Schubel, 1972). Bival-ves are known
to absorb and store copper, mercury, lead and arsenic
(Galtsoff, 1960,,). Oysters, clams and scallops concentrate
zinc 100,000 times that of surrounding water (Cronin, 1967).
It should be realized that the presence of heavy metals
in Chesapeake Bay is not unusual; they occur there naturally.
They result from weathering and erosion and are absorbed by
fine sediment particles. Man has, however, increased the
concentrations of these heavy metals (e.g., in the molecular
makeup of pesticides) and hence has accelerated their harm-
ful biological effects. It must be remembered that these
materials are "non-biodegradable" and thus have a long
lifetime and that physical, chemical and biological
processes may have a combined effect of concentrating
these metals making them potentially dangerous pollutants
(Frazier, 1972). The concentrations of heavy metals in
,the Susquehanna River are associated with suspended sediments

Appendix 15,
401

(Schubel, 1972) and with vegetation (Williamson, 1972).
Concentration in the Bay are greatest at the head of
the estuary (Williamson, 1972); it is here that the
shellfish grounds are closed periodically.

Few reports-regarding radioactive waste in the
Chesapeake have been made, but it is known to be enter-
ing the Bay in increasing quantities (Cronin, 1967). Radio-
active chemicals with a short half life (the time required
for half of a radioactive particle to decay) may not be
critical, but the presence of ones prossessing a long half
life probably have some effect on the biota. As they pass
through the various trophic levels of a biological system,
these chemicals, as well as heavy metals and pesticides,
become more and more concentrated. They may be cycled and
recycled, but eventually,enter human food supplies in
significant enough quantities to be a health hazard (Cronin.
1967). Their presence is especially dangerous because they
are caDable of altering genetic structure.

The process of sedimentation also can affect the biota.
(Some of these effects were mentioned Previously in Chapter III).
Dredging, an activity necessary to keep shiD channels oDen;
involves deposition of spoil which can cause smothering of
benthic organisms. Other engineering activities such as
fillinR for parks, industry, housing and airports, shore-
line construction, dynamiting, cutting of waterways and
canals and some specialized fishing operations, e.g.,
hydraulic dredging for softshell clams, all contribute
to sedimentation problems if they are not controlled (Cronin,
1967a). Other biological effects caused by sediments listed
by Sherk (.1972) are: (1) they can reduce light penetration,
thereby reducing photosynthetic activity, (2) the resus-
pension of sediments can harmfully affect the biota if
the oxygen demand is critical since the suspended particles
exert an oxygen demand eight times greater than bottom
deposits and (3) the suspended particles will also stimulate
community respiration probably by organic matter accompany-
ing inorganic turbidity. The organic matter is absorbed
by inorganic particles or mud and concentrated to 100,000
times its dissolved value. These inorganic-organic
complexes provide a substrate for bacteria by concentrating
substances from the water that attract bacteria and
retarding the diffusion of enzymes.

Appendix 15
402

As mentioned earlier in this section, wetlands are
sediment depositories. The inorganic sediment from the
rivers and the organic sediment originating in the marsh
are transported via the marsh drainage system to the
estuary. The channels that flood and drain these areas
are 11critical transport links in delivering detritus and
nutrients to the estuarine food chain" (Williamson, 1972).
Figure 15-33 clearly demonstrates nutrient exehange between
the marsh and the estuary. It is now apparent to many
state and Federal agencies that a wetland is one of the
most important production units in a bay.

One form of pollution that often makes the headlines
in our environmentally awakening society is that of thermal
pollution. For years the American society has taken power
for granted, but now because of the "energy crisis", every-
one is aware of a power shortage. At the same time that power
companies are trying to expand to produce more power.,
environmentalists are trying to hinder expansion because
of alleged deleterious environmental effects. Opinions
regarding the "harm" of heated effluents from power plants
are controversial. It is known that thermal additions
can and do cause algal blooms out of season and block
fish migration. Young and Gibson (1973) reported the death
of juvenile menhaden due to thermal shock. Few reports of
menhaden kills have been made. However, Young and Gibson
pointed out that the type of fish kill where the dead
fish sink rather than float often goes unnoticed. In this
particular case, the detrimental effect was-observed only
because scuba divers happened to be at the right place at
the right time. The question arises as to how often the
effects of thermal additions have previously not been
reported simply because of the veil of water covering a
bay bottom.

A form of environmental alteration often overlooked
is biological pollution, e.g., the introduction of exotic
species. A review of the literature indicates that "trans-
portation of oysters, oyster shell, and seed has probably
modified the distribution of more aquatic species than any
other human activity" (Cronin,, 1967). For example, the
introduction of the American oyster into the English Channel
resulted in the spread of Urosalpinx cinerea, an oyster
drill. In the Chesapeake bay the introduct-i n of Eurasian
milfoil (previous distribution restricted to Europe, Asia
and Africa) has blocked navigation, prevented boating and
swimming, and interfered with seafood harvests.

Appendix 15
403

S u IN
Vol

P
Off J(

oil

NUTRIENT
S EA WATER
EXCHANGES

Iflustic;1100 shows YCIQ Of exchange
of nutriams b*hv4oft 'norsh vnd see

!.L'ANT P.1;A-0KT0N'.

P
TMA L

ECAY.

FIGURE 15-33: EXCHANGE OF NUTRIENTS BETWEEN MARSH AND SEA
(Odum and Copeland, 1974)
0
L11N

Appendix 15
404

Cronin (1967) reported on the factors that provide the
Chesapeake Bay with resiliency, but at the accelerating
rate of pollution, it will be difficult for the Bay to
continue its cleansing process. Water managers will be
responsible for protecting the environmental quality of
the Bay. Failure can result from several sources of
error or insufficiencies. Cronin (1971) listed these as:

1. "Incorrect population prediction."

2. "Erroneous estimates of. the quality or nature
of industrial activity."

3. "Continuation of the existing philosophy of
the right to use public water for waste disposal."

4. "Inadequate knowledge of the assimilation and
biological effects of unknown new compounds."

5. "Erroneous engineering data or calculation."

6. "Insufficient understanding of the biological
system and population affected."

7. "Deficiency of funds."

8. "Mechanical break-down in equipment."

9. "Operational error."

10. "Inadequate enforcement."

11. "Weakness in legislation."

12. "Political pressure."

Management has a massive job ahead of itself if it is
going to prevent the Bay from reaching a point of no
return. Cronin (1971) listed the capabilities of tech-
nology to control various pollutants (Table 15-32) but
he also pointed out "the levels of results which are
rgenerally' acceptable' are rapidly changing and generally
rising."

AT)Pendix 15

TABLE 15-32
CAPABILITIES OF TECHNOLOGY FOR CONTROL OF VARIOUS POLLUTANTS
(Cronin, 1971)

Pollutant Teahnological Capability

I. Suspended solids
(a) Settleable adequate
(b) Colloidal adequate

II. Dissolved solids
(a) Inorganic
1. Total di6solved solids available*
2. Nitrogen compounds inadequate
3. Phosphates available*
4. Trace metals inadequate
5. Heavy metals adequate
6. Acidity adequate
7. Alkalinity adequate
8. Radioactive elements adequate
(b) Organic
1. Biochemical oxygen demand adequate
2. Refractory materials
(i) Detergents adequate
(ii) Pesticides -inadequate
(iii) Residues inadequate
(iv) Industrial inadequate

III. Thermal pollution adequate

IV. Living organisms
(a) Infectious agents
1. Bacteria adequate
2. Viruses inadequate
(b) Plants
1. Attached available*
2. Algae adequate
(c) Slimes inadequate

Economically limited.

Appendix 15
406

FUTURE NEEDS AND REQUIREMENTS

If the quality of the Chesapeake Bay environment is to
41 be maintained and improved, a sound management structure,
based on planning and expanded research is needed. Unfor-
tunately, the existing state of the art does not always
allow a complete understanding or statement of biologic
factors or conditions as input to management decisions.
An increasingly detailed accumulation of data and knowl-
edge is needed for Bay Area managers to adequately
assess complex interactions.

Information, in a readily interpretable form, must be
madeeavailable to the management decision makers by the
scientific community. A key step in this direction would
be completion of the 1'ife histories of "Important Bay
Area Species:' The life histories completed thus far for
the Chesapeake Bay Study represent about one-fourth of
the species identified as being important in Chapter IV.
The completion of these histories for the remaining
species would represent a significant link toward sys-
temization of available knowledge of the Bay biota.
Also, additional work is needed on the biotic communities
of Chesapeake Bay to supplement the typp of information
presented in Chapter VI.

Expanded and intensified environmental watchfulness and
enforcement of water quality regulations are another'
urgent need. Continued and intensified monitoring cpro-
grams are needed for early problem identification and
to assess the physical effects of water management pro-
grams and policies. Early identification of environ-
mental problems would aid in reduction or localization
of damage.

The status of knowledge of predominant species found in
Chesapeake Bay has been presented partially in this
appendix and partially in the Biota Section of the
Existing Conditions Report (ECR). As part of these
"biological.life summaries," information gaps are iden-
tified which require specific research attention. Other
research needs are also specifically stated in the
Existing Conditions Report concerning the effects of
parameters such as sediments, nutrients, heavy metals,
and pesticides. Shortcomings in knowledge involving
the effects in the environment of oil and chlotine are
included as part of-the presentation in Chapter VII of
this appendix.

Appendix 15
407

In summary, it should be stated that, regardless of the
tangle of laws, programs, and projects considered to
enhance and protect the Bay environment, farsighted and
deliberate leadership will be required to assure results.
As the drive for increased utilization of resources
unfolds in the future, in response to needs for our grow-
ing population and continued economic development,
courageous decisions will be needed to assure an ecological
balance. Economic considerations have historically governed
the decision making process. Society must now begin to
realize the value of its natural heritage and be ready to
make the hard decisions necessary to protect it.

MODEL TESTING APPLICATIONS

As explained in Chapter I, a hydraulic model of Chesapeake
Bay has been part of the Bay Study Program since its
authorization in 1965. The model will prove a valuable
decision making tool in many resource areas, including
biota. The effects of natural and/or man-induced changes
in the Bay, for example, can be evaluated by the scientific
community to predict effects on the biota. Information
derived from model tests concerning salinity distributions,
currents, waste dispersion, tidal surges,, and low fresh-
water inflow, among others, in conjunction with knowledge
of the biota (distribution reproduction, community
structure, limiting factors, etc.), would allow for an
informed decision making process.

Although hydraulic models have been used for many years
in dredging studies relative to navigation, their aid
in attempting to understand biological processes has
been largely neglected. Probably the reasons for this
slow development can be attributed to the relatively
few models constructed of the estuary or river where
biological research is conducted and the comparative
inaccessibility of the actual model to the scientists
Wishing to use them. Another factor may be that the
scientific community was not familiar with the capabil-
ities of the physical models and instruction on its
potential uses was not made available.

Appendix 15
408

With the construction of the Chesapeake Bay Hydraulic
Model on Kent Island, Maryland, many of these limitations
are removed. This model, of the largest and probably
most important estuaries in the world, will soon be
available for investigators who might have use for such
an instrument. Also, this model is probably accessible
to more scientists than any other similar model yet
constructed.

As part of Chesapeake Research Consortium's contract,
an inventory was conducted to identify the problems
among the biota and physical processes.in the Byy that
lent themselves to practical studies on the Bay Model.
In the Existing Conditions Report, 1973, the CRC iden-
tified and inventoried scientists, especially biologists,
who are active in Chesapeake Bay research. (Kerby and
McErlean, 1972). Approximately 1,200 workers were con-
tacted of which 644 responded. This list of respondent
investigators formed the basis of the participants in
the questionnaire survey for data on biological uses
of the hydraulic model. The survey was coordinated
through Dr. Hayes T. Pfitzenmeyer, University of Maryland,
Solomons, Maryland.

A total of 559 questionnaires were sent to scientists
from this above list and a list of other more recent
personnel involved in Bay research, of which 85 were
returned. This rate of response must be considered
good if one examines the type of information solicited
on the questionnaire. It was decided that a "question
and answer" type of survey would provide more infor-
mation than merely a "choice" type questionnaire even
though the percent response would be less. The
respondents were not requested to identify themselves,
which, hopefully, was to give more freedom on imagina-
tive answers.

A sample questionnaire, explanatory cover letter, list
of model capabilities, and "summation of replies" from
the scientific community are found in Attachment 15-D.
It was felt important to retain as much original wording
and individual thought as possible; therefore, the answers
are essentially the same as received. Only word-for-word
duplication of ideas, as.well as personal references, have
been eliminated. Some of the biologicil studies expressed
on the questionnaires, in the wkiter's opinion, cannot
possibly be conducted with the model as detigned; however,
these ideas were also included in the replies. These fall
into the categories of direct observation of particular
biological phenomena.

Appendix 15
409

Possible uses of the hydraulic model as an aid in
understanding particular biologically related problems
have been summarized and presented in Figure 15-34.
These are the physical and chemical parameters upon
which biological systems in the Bay are so dependent.
For an orderly placement, the possible uses as listed
on the returned questionnaires, have been arranged
under,three major headings: hydrographic, or those
studies concerned with water quality or movement;
topographic, those involving physical change; and
instructional,which is concerned with education,
demonstration, and tests to prove some particular
theory or mathematical model. Under each of these
major headings of concern are the general physical and
chemical investigations capable of being tested with the
hydraulic model in order to explain some biological
phenomena. More specific studies are listed below each
of these as one or two word summaries. These are the
areas of investigation, as suggested by the canvassed
scientific personnel, to which the hydraulic model may
be employed.

Studies dealing with specific organisms or biological
activities which may be investigated with the hydraulic
,model are ranked in the order of the number of times
they appeared on the questionnaires. Results are pre-
sent.ed in Table 15-33. Replies to the first question,
pertaining to the research in which they are presently
engaged, are separated from the answers to the second
question which dealt. with their opinion of possible
uses of the model. These two lists are very similar,
which may be expected since both questions were com-
pleted by the same person with specific interests in
a particular field of research. It is of interest to
note that the hydraulic model has uses in practically
all phases of biological research, including algae,
rooted aquatic plants, bacteria, invertebrates, and
vertebrates.

Several investigators pointed out that direct biological
simulation with a hydraulic model as an impossibility
and would probably lead to erroneous results. The research
would have to be of the physical and chemical nature as
diagrammed in Figure 15-34, and then applied to data from
the prototype bef9re it would be-of any biological value.

An inquiry'as to the amount of knowledge various inves-
tigators have had withother hydraulic models indicated
a general lack of experience in this field. The James
River Hydraulic Model used by the Virginia Institute of
Marine Science with reference to oyster larvae distri-
bution was the most well-known. Other models referred

Appendix 15.
410

HYDRAUL I

BIOLOGICAL STUDIES RELATIVE TO
SPECIES ECOLOGY AND TOLERANCES

Hydrographi c@ IT.opograph 1@c lInstructional

Tides an Flushing Spatial and
A
Current Rate Temporal Artificial Nat ral cation]
[Salinity

Circulation Seasonal Mechanics Nutrients Channel Erosion Math Model Student
Pollutants Variation Dredge Sedimen- Energy Flow Public
Upwellings Waste Toxic tation
Surges Vertical Disposal Chemicals Spoil
Storms Mixing Disposal
Silt Residual Suspended
Time Sediments Impoundments
Breakwaters
Anoxic Currents Land-fills
Zone Salinity

Sinks

FIGURE 15-34: MODEL STUDIES APPLICABLE TO BIOLOGICAL PROBLEMS

TABLE 15-33
RANKING OF BIOLOGICAL APPLICATIONS
FOR THE BAY MODEL

Uses Related to Present Research Possible Uses in General

1. Planktonic organisms 1. Plankton distribution
2. Fish movements 2. Shellfish larvae dispersal
3. Menhaden larval transport 3. Menhaden transport
4. Sea nettle distribution 4. Invertebrate larvae
5. Nursery area production S. Oyster spawning
6. Fish distribution 6. Fish larvae
7. Juvenile blue crab 7. Eelgrass distribution
dispersal 8. Bacteria and virus patterns
8. Shellfish setting 9. Algae growth
9. Flora and fauna changes 10. Crustacean recruitment
10. Oyster hatcheryiwork 11. Fish eggs movements
11. Bacterial associations 12. Microbial pollutants
12. Benthic invertebrate 13. Clam spawning/setting
ecology 14. Oyster drills
15. Disease organisms
16. Benthic invertebrate
ecology

ADDendix 15
412

to were the Waterways Experiment Station model of the
Chesapeake and Delaware Canal, the model of the Hudson
estuary and New York Bight, and the Narragansett Bay
Model. Private ownership, availability, and physical
limitations of the model have apparently restricted
usage of the models in the past. These will be eli-
minated with the completion of the Chesapeake Bay
Hydraulic Model.

Prototype data which may be made available to various
investigators for use in conjunction with model studies
appear to cover a wide range of activities. Many of
these data have appeared in previous publications and
are already available to the scientific community. Some
investigative institutions have been collecting data for
many years and these will never appear for public dis-
tribution but are available from their files for general
usage. Specific knowledge of data required and famil-
iarity of the many research institutions of the Chesa-
peake area is necessary. As the Chesapeake Bay Hydraulic
Model matures, a reference library of such available data
and where it may be located can be incorporated in its
facilities for scientific investigators.

Mathematical modeling of entire biological systems is
becoming more common as research data on specific processes
and interactions are made available. These conceptual
models remain more or less in the realm of theory unless
they can be proven to be correct. One method of testing
would be through the use of the hydraulic model. Also,
the hydraulic model can be used in many instances to
obtain input data for the numerical model. The summary
of responses to this question on mathematical biological
techniques is interesting and indicates the importance
of computer science in biological research. More and
more research personnel are being trained in this area
and the hydraulic model will become an essential instru-
ment of their progress.

Appendix 15
413

GLOSSARY

absorption: the process by which a substance is
taken up by, or penetrates into, another.

acclimation: the physiological and behavioral
adjustments of an organism to changes
in its immediate environment.

adsorption: the adhesion of a substance to the
surface of a solid or liquid.

aerobic: refers to life process occurring only
in the presence of oxygen or air.

algae: any of a group of plants found in
water, with chlorophyll, but without
true root, stem, or leaf; includes
diatoms.

amphibian: any of a clan of vertebrate animals
passing through an aquatic larval stage
with gills, and a terrestrial stage
with lungs; includes frogs, toads,
salamanders.

amphipod: any of several crustaceans with one
set of feet for jumping and another
for swimming (e.g., the sand flea).

anadromous: type of fish that ascend rivers from
the sea to spawn.

anaerobic: refers to life or process occurring
in the absence of oxygen or air.

angiosperm: any of a class of plants, including
all the flowering plants, having the
seeds enclosed in an ovary (opposed
to gymnosperm).

anoxic: totally deprived of oxygen.

aquatic: of or pertaining to fresh or salt
water; growing or living in or
upon water.

benthic: of or pertaining to the bottom of
a water body.

Appendix 15
415

benthos: those organisms living on or in the
bottom of a water body.

biomass: total mass or amount of living organisms
in a given area.

biota: the plant and animal life of a region.

bivalve: any of a class of mollusks having
two shells hinged together, e.g.,
clams and oysters.

biochemical oxygen
demand (BOD): a measure of the oxygen depleting
power of the organics in a waste
water discharge.

catadromous: going back or toward the sea to spawn;
said of certain freshwater fishes,
including American eel.

chlorinated hydro-
carbons: a class of generally long-lasting
insecticides, variously hazardous
through accumulation in the food
chain and persistence in the envi-
ronment.

clupeid: any of a family of soft-finned fishes,
as herring.

community: (in biology) an accumulation of diverse
organisms living together in an orderly,
interrelated manner.

consumer, primary: an organism which consumes green plants.

consumer, secondary: an organism which consumes the primary
consumer.

copepods: any of a subclass of small crustaceans
of fresh or saline waters; a components
of the zooplankton.

curstacean: a large class of invertebrate animals,
usually aquatic, bearing a horny shell
(e.g., lobster, shrimp, and barnacles).

DDT: most infamous of the chlorinated
hydrocarbonsinsecticides.

Appendix 15
4 1 CA

dissolved oxygen
(DO): oxygen gas dissolved in water, necessary
for life of fish and other aquatic
organisms; becomes depleted by high
BOD-containing waste.

detritus: a non-dissovled product of disinte-
gration or decay; organic detritus
forms the basis of the estuarine
food chain.

diatom: any of a class of minute, planktonic
or attached unicellular or colonial
algae.

dominnnt: said of an organism that controls the
habitat or has profuund influence in
a biotic community, often the most
conspicuous.

ecology: the interrelationships of living things
to one another and their environemnt;
or the study thereof.

ecosystem: the interacting system of a biological
community and its environment.

endemic: indigenous or characteristic of a
particular locale.

epiphyte: a plant that grows on another plant
but is not a parasite, producing
its own food by photosynthesis.

epizootic: an epidemic disease among the animals.

estuary: the zone of mixing of freshwater runoff
from the land and salt water from the
intruding ocean.

ethology: the scientific study of the behavior
patterns of animals.

euphotic zone: the upper layers of a water body in
which sufficient light penetrates to
allow growth of green plants.

euryhaline: of/aquatic organisms capable of
surviving a wide range of salinities.

Appendix 15
417

eurythermal: of/an organism capable of living
in a wide range of temperatures.

eutrophication: (lit. "well fed") a. process whereby
waterways become overgrown with plant
growth due to overenrichment; generally
cuased by nutrient loads from waste
discharges and agricultural runoff.

fauna: the animals of a given region, as
opposed to the "flora."

flora: organisms of the plant kingdom occurring
in a particular area.

freshet: a stream or rush of freshwater flowing
into an area.

game fish: those species of fish sought by sport
fishermen.

habitat: the total of environmental conditions
affecting an organism, population, or
community.

herbicide: a chemical substance used to kill
plants or inhibit plant growth.

holoplankton; an organism which spends its entire
life cycle as a member of the plankton
community.

hydrophyte: a plant which grows in water or very
wet earth.

indigenous: of/native species, not introduced.

interstitial waters: that occurring in the voids of bottom
sediments.

intertidal: of or having to do with the region of
shoreline extending from low to high
tide marks.

invertebrate: any animal lacking a backbone (e.g.,
insects, mollusks, and crustaceans).

is'ohaline: a line of constant salinity.

Ile
Appendix 15
418

larva: an early developmental stage of an
animal which changes structurally to
become an adult (e.g., caterpillars,
tadpoles).

life cycle: the phases, changes, or stages in which
an organism exists during its lifetime.

limiting factor: a variable in the environment which
limits the distribution or abundance
of a particular organism.

limnology: the study of the biological, chemical,
and physical features of inland waters.

macrofauna: the large (visible to the naked eye)
animals of an area.

marine: of or pertaining to the sea or ocean.

marsh: a tract of low-lying, soft, wet land;
a swamp dominated by grasses or grass-
like vegetation.

meroplankton: organisms that spend only a part of
their life cycle as a member of the
plankton.

microbiota: the microscopic organisms present in
an area.

mollusk: any of a phylum of invertebrate animals,
including clams, oysters, snails, and
octupi.

morphology: the study of the form and structure of
an organism.

muck: soils composed of decaying plant
materials.

nanoplankton: microscopic, free-floating aquatic
organisms.

nekton: free-swimming aquatic animals, whose
movements are largely independent of
water currents, e.g., adult fish and
crabs.

nocttrnal: occurring or actvve during hours of
darkness; said of owls, bats, and
many other animals.

iiPpendix 15
419

non-vascular plants: plants without specialized conductive
tissues, eig., algae, mosses.

nutrients: elements or compounds essential for
biological productivity; a pollutant
when in excess in waterways, causing
excessive plant growth.

nutrient cycling: the movement of nutrients from the
non-living (abiotic) component of
the environment, through the living,
and with time,. back to the abiotic.

nymph: immature stage of arthropods (primarily
insects) that is not markedly different
from the adult.

oligohaline: of or pertaining to low chloride
concentrations.

omnivorous: eating a wide variety of food, both
plant and animal.

organic: of or derived from living organisms;
typically contains carbon and hydrogen.

organism: any individual plant or animal having
parts or organs that function together
to maintain life and its activities.

oxygen sag: a drop in 02 concentration; caused in
streams by gradual decay of organics
in waste discharges.

parameter: a measurable, variable quantity.

passerine: chiefly perching; sonkbirds,as opposed
to waterfowl and raptors.

periphyton: community of organisms usually small
but densely set, clos -ely attached to
stems and leaves of rooted aquatic
plants or other sutfaces projecting
above the bottom.

pesticide: toxic chemical used to kill problem 4q
plants and animals--insecticides,
herbicides.

pH: a numerical expression of acidity;
the negative logarithm of hydrogen
ion concentration.

ADpendix 15
420

photosynthesis: the process in plants of production of
carbohydrates from carbon dioxide and
water, using sunlight as energy, and
chlorophyll as a mediator.

phytoplankton: plankton consisting of plants; e.g.,
algae.

plankton: usually microscopic plant and animal
life found drifting or floating in a
water body; if mobile, only weakly so.

pollution: an additive to a particular environment
rendering it of reduced utility or
benefit.

polyp: any of various coelenterates having a
mouth fringed with many small slender
tentacles at the top of a tube-like
body.

predator: an organism living-by capturing and
feeding upon other animals.

productivity: the rate of production or organic
matter produced by biological activity
in an area (measured in units of weight
or energy per unit volume and time).

protist: any of a large group of one-celled
organisms having both plant and animal
characteristics, e.g., algae, bacteria,
protozoans.

psammofauna: animals living in water held between
sand grains in waterlogged sands.

raptors: any of a group of birds of prey,
including hawks, falcons, eagles,
and owls.

red tide: an excessive bloom of red-pigmented
plankton, capable of causing massive
fish kills.

relict: said of a species "left behind,"
belonging to an earlier period or
community type, now living in isolation
in a small local area.

Appendix 15
421

reptiles: one of the major groups of cold-blooded
vertebrate animals, generally having
scales and true lungs (e.g., snakes,
turtles, lizards).

resilience: in biology, the ability of an ecosystem
to resist or recover from stress.

respiration: breathing; in biology, the oxidative
breakdown of food by organisms to
produce life energy.

salinity: a measure of the concentration of
dissolved solids in water.

salt marsh: grass-dominated, flat, intertidal area,
inundated periodically (seasonally or
by the tides) with saline water.

saprophyte: any organism living on dead or decaying
organic matter, includes some fungi
and bacteria.

sedentary: remaining in one locality; not migratory.

sedge: a type of low grass-like plant with a
triangular cross-section, usually occur-
ring in wet areas.

sessile: attached, stationary, non-moving
(e.g., oysters, barnacles).

seston: a collective term for everything floating
or suspended in water, including plankton
and detritus.

shell fish: aquatic animals having a shell or
exoskeleton, usually mollusks (clams
and oysters).

siltation: a process whereby small suspended
particles are deposited in a water body
as sediment.

spawn: to produce or deposit eggs, sperm, or
young.

species: a distinct kind; a population of plant
or animal all having a high degree of
similarity and that can generally only
breed among themselves.
Appendix 15
422

stenohaline: of/organisms which can endure only a
narrow range of salinities.

succession: the replacement of one community by
another through a regular sequence
of changes over time.

synergism: the superimposed effects of separate
pollutants or substances so that the
total effect is greater than the sum
of the effects independently.

taxonomy: the system of arranging animals and
plants into related groups based on
structure, embryology, biochemistry,
etc.

terrestrial.- of or pertaining to dry ground, as
opposed to "aquatic."

thermal pollution: the abnormal raising or lowering of
water temperatures above or below
seasonal ranges.

toxicity: the quality or degree of being poisonous
or harmful to an organism.

trophic level: comprised by all organisms in a complex
community that derive their food a com-
mon step away from the primary producer.

turbidity: the condition of water containing con-
spicuous amounts of suspended material.

upland: all areas of land above the depressions
occupied by lakes, rivers, swamps, or
seas.

vascular plants: pl-ants that have xylem and phloem to
convey water and food.

vertebrate: those animals possessing a backbone or
spinal column, i@e., fishes, birds,
reptiles, amphibians, and mammals.

waterfowl: birds frequenting water, including game
birds such as ducks and geese.

wetlands: an area characterized by high soils
moisture and high biological productivity,
where the water table is at or near the
surface for most of the year.

zooplankton: plankton consisting of animals, as protozoa.

Appendix 15
423

ATTACHMENTS

ATTACHMENT 15-A
LETTER AND QUESTIONNAIRE CIRCULATED
TO DETERMINE "IMPORTANT" BAY AREA SPECIES

UNIVERSITY OF MARYLAND
NATURAL RESOURCES INSTITUTE

CHESAPEAKE BIOLOGICAL LABORATORY
BOX 30
SOLOMONS. MARYLAND 2008

The Chesapeake Research Consortium is attempting to further summarize
knowledge on the condition of the biota of the Chesapeake Bay by continuing
the program under the sponsorship of the U. S. Army Corps of Engineers.
You may recall, and probably participated in the first comprehensive efforts
which were published in a special supplemental issue of Chesapeake Science.

As a further aid to future resource management.programs of the Bay, we
are presently attempting to compile a list of "important" species as far as
our present knawledge will permit. Realizing that such a list in many in-
stances is a result of subjective opinions, we would like to gain the benefit
of your expertise on a particular group of organisms.

The enclosed form lists species from a particular phylum or group of
organisms with which we think you are quite familiar. These are species we
believed should be considered as important. If in vour opinion thev do not
meet the criteria for 'importance within the Bay system, then eliminate them
from the list. If other species should be considered, then please add them
in the spaces provided.

Included on the form is a list of 15 very general criteria, some of
which are prerequisites for "importance" while others viere included to gain
the benefit of your knowledge of the species. Would you please evaluate
the species on the list, and any species you night add, according to these
characteristics? Many of these categories do not apply to your particular
group since we have tried to use one form for all groups of organisms. We
hope that evaluation according to the brief key shown on the form will not
require an undue amount of time.

Any assistance you may be able to give us on this undertaking will be
appreciated, and you will receive proper acknowledgment in all forthcoming
reports. Thank you for the benefit of your experience and the valuable time
you are able to afford us for this request. If for some reason you are not
able to complete the form, would you please pass it on to one-of your col-
leagues whom you feel would be similarly qualified?
Sincerely,

Hayes T. Pfitzenmeyer
Research Associate

enc.

Appendix 15
A-1

ATTACF(MENT 15-A (cont'd)
LETTER AND QUESTIONNAIRE CIRCULATED
TO DETERMINE "IMPORTANT" BAY AREA SPECIES

IMPORTANT BAY SPECIES

Ccmpiled by Phylum or group

Key:

+ = Yes

- = No

0 = No info available

1. Con-mercial species
2. A sport species

3. Predator of a commercial or sport species

4 Food for a commercial or sport species

5. Damaging to human interests or activities

6 Indicator of presence of pollutants

7 Human influence detrimental

8. A significant biomass at some trophic level

9. Critical link in energy flow in food chain

10. Seasonal in ecological significance

11. An eruptive species

12. Wide geoqraphic distribution
L3- Narrowly defined.habitat
4. Migratory
F5.1 Can becultured in controlled environment

Appendix 15
A-2

ATTACHMENT 15-B
INVENTORY OF WETLAND COMMUNITIES

I. Low saltmarsh community

Dominant plants
Saltmarsh cordgrass (Spartina alterniflora)

Dominant animals
Periwinkle (Littorina irrorata)
Ribbed mussel (Modiolus demissus)
Marsh fiddler (Uca pugnax)
Diamond-back terrapin (Malaclemys terrapin)
Mummichog (Fundulus heteroclitus)
Clapper rail (Rallus longirostris)

II. High saltmarsh community

Dominant plants
Saltmarsh cordgrass (Short-form) (Spartina alterniflora)
Saltmeadow hay (Spartina patens)
Saltgrass (Distichlis spicata)
Black needlerush (June roemerianus)

Subdominant plants
Saltmarsh pluchea (Pluchea purpurascens)
Saltmarsh fimbristylis (Fimbristyis spadicea)
Saltwort (Salicornia - 3 sp.)

Dominant animals
Saltmarsh mosquito (Aedes sollicitans)
Greenhead Fly (Tabanus nigrovittatus)
Saltmarsh snail (Melampus)
Long-horned grasshopper (Orchelimus)
Sharp-tailed sparrow (Ammospiza caudacuta)

Subdominant animals
Willet (Catoptrophorus semipalmatus)
Seaside sparrow (Ammospiza maritima)

III. High salinity creek community

Dominant animals
Mummichog (Fundulus heteroclitus)
Striped killifish (Fundulus majalis)
Blue crab (Callinectes sapidus)
Great blue heron (Ardea cinerea)

Subdominant animals
Atlantic silverside (Menidia menidia)
Sheepshead minnow (Cyprinodon variegatus)

Appendix
B-1

ATTACHMENT 15-B (cont'd)
INVENTORY OF WETLAND COMMUNITIES

White mullet (Mugil curema)
Striped mullet (Mugil cephalus)
Naked goby (Gobiosoma bosci)
Menhaden (Brevoortia tyrannus)
Oyster toadfish (Opsanus tau)
Laughing Gull (Larus atricilla)
Forster's Tern (Sterna forsteri)

IV. Oligohaline marsh community

Dominant plants
Big cordgrass (Spartina cynosuroides)
Punctate smartweed (Polygonum punctatum)
Narrow-leaved cattail (Typha angustifolia)
Saltmarsh bulrush (Scirpus robustus)
Saltmarsh cordgrass (Spartina alterniflora)
Pickerelweed (Pontederia cordata)
Marsh hibiscus (Hibiscus moscheutos)

Subdominant plants
Swamp cock (Rumex verticillatus)
Olney threesquare (Scirpus olneyi)
Common threesquare (Scirpus americanus)
Great bulrush (Scirpus validus)
Saltmarsh mallow (Kosteletskya virginica)

Dominant animals
Muskrat (Ondatra zibethicus)
Raccoon (Procyon lotor)
Red-jointed fiddler (Uca minax)
Great blue heron (Ardea cinerea)

Subdominant animals
Long-horned grasshopper (Orchelima sp.)
Long-billed Marsh Wren (Te1matodytes palustris)
Red-winged blackbird (Agelaius phoeniceus)

V. Oligohaline creek community

Dominant animals
Mummichog (Fundulus heteroclitus)
American eel (Anguilla rostrata)
White perch (Morone americana)
Bluegill (Lepomis gibbosus)
Garfish (Lepisosteus osseis)
Snapping turtle (Chelydra serpentina)
Great blue heron (Ardea cinerea)

Appendix 15
B-2-

ATTACHMENT 15-B (cont'd)
INVENTORY OF WETLAND COMMUNITIES

Subdominant animals
Otter (Lutra canadensis)

Black duck (Anas platyrhynchos rubripes)
Belted kingfisher (Ceryle Alcyon)
Menhaden (Brevoortia tyrannus)
White catfish (Ictalurus catus)
Sheepshead minnow (Cyprinodon variegatus)
Banded killifish (Funduius diaphanus)
Tidewater silverside (Menidia beryllina)
Pumpkinseed (Lepomis gibbosus)
Naked goby (Gobiosoma bosci)
Hogchoker (Trinectes maculatus)

VI. Freshwater tidal marsh community

Dominant plants
Arrow arum (Peltandra virginica)
Pickerelweed (Pontederia cordata)
Wild rice (Zizania aquatica)

Rice cutgrass Leers oryzoides)
Swamp dock (Rumex verticillatus)
Punctate smartweed (Polyonum punctatum)
Narrow-leaved cat-tail (Typha angustifolia)
Beggars-tick (Helenium autumnale)

Subdominant plants
Common cat-tail (Typha latifolia)
Southern wild rice (Zizaniopsis miliacea)
Walter's millet (Echinochloa walteri)
Arrow-leaved tearthumb (Polygonum sagittatum)
Halberd-leaved tearthumb (Polygonum arifolium)

Dominant animals
Raccoon (Procyon lotor)
Muskrat (Ondatra zibethica)
Red-winged blackbird (Agelaius phoeniceus)
Bullfrog (Rana catesbeiana)
Great blue heron (Ardea cinerea)
King rail (Rallus Longirostris elegans)

Subdominant animals
Northern water snake (Natrix s. sipedon)
Green frog (Rana clamitans melanota)
Southern leopard frog (Rana sphenocephala)
Otter (Lutra canadensis)
Mink (Mustela vison mink)
Long-billed marsh wren (Telmatodytes palustris)
Green heron (Butorides virescens)
Yellowthroat (Geothlypis trichas)

Appendix 15
B-3

ATTACHMENT 15-B (cont'd)
INVENTORY OF WETLAND COMMUNITIES

VII. Freshwater tidal creek community

Dominant plants (great variation with locality)
Eurasian water milfoil (Myriophyllum spicatum)
Horned pondweed (Zannichellia palustris)
Yellow pond lily (Nuphar luteum)

Subdominant plants
Readhead grass (Potamogeton perfolatus)
Wildcelery (Valisneria americanana)
Sago pondweed (Pota ogeton pectinatus)

Dominant animals
Snapping turtle (Chelydra serpentina)
Red-bellied turtle (Chrysemys rubriventris)
Eastern painted turtle (Chrysemys p picta)
American Coot (Fulica americana)
Belted kingfisher (Ceryle alcyon)
American eel (Anguilla rostrata)
Carp (Cyprinus carpio)
White catfish rus catus)
Bluegill (Lepomis macrochirus)
Pumpkinseed (Lepomis gibbosus)
Largemouth bass (Micropterus salmoides)
Chain pickerel (Esox niger)
Black crappie (Pomoxis nigromaculatus)

Subdominant animals
Dragonflies (Odonata)
Midges (Tendepedidae)
.Mosquitoes (Culicidae)
Spattail shiner (Notropis hudsonius amarus)
Pirate perch (Aphredoderus sayanus)
Golden shiner (Note igonus c. crysoleucas)
Creek chubsucker (Erimyzon a. oblongus)
Banded killifish (Fundulus diaphanus)
Mosquito fish (Gambusia affinus)
Yellow perch (Perca flavescens)
Eastern mudminnow (Umbra pygmaea)
Northern water snake (Natrix s. sipedon)
Pied-billed grebe (Podiceps auritus)
Canada goose (Branta canadesiss)
Wood duck (Aix sporsa)
Mallard (Anas p. platyrhynchos)
Black duck (Anas platyrhynchos rubripes)
Pintail (Anas acuta)
American widgeon (Anas penelope)
Green-winged teal (Anas carolineansis)
Ring-necked duck (Aythya collararis)
Bufflehead (Bucephala albeola)
Common merganser (Mergus merganser)
Ring-billed gull (Larus delawarensis)
Appendix 15
B-4

a) ZONATION OF DOMINANT MACROBENTHOS IN THE POLYHALINE ZONE

Shallow Deep
Medium Sand Fine Sand Muddy Sand Silt-Clay
Leptosynapta tenuis (E)
Gemma gemma (9)
Ampeli-E-caverrilli (A) z
N s picta (P) A
z
SpiopFan_i@_sbombyx (P)
Te 11 in
a agilis B)
Phoro s psammophila (Ph)
Ampelisca vadorum (A)
s magellanica (P)
- - - - - - q zued-
lymenella tor ta (P) 0
z .4
Turbonilla interrupta (G)
n-t ..........
Macoma_l@e_ a B3__
0
Pelos-CoTe-xgabriellae (0)
Ceriantheopsis americana (An)
Acteocina canalT-culata (G)
Mu I i n i a-1 aTe-r-a-I M Ln
z
meteromastus.fi7iformis (P)
Spioch@i_etopt s oculatus (P)
Pseudeurytioe sp.-T-P7-
Edward@_i_aelegans (An)
Parapr o9_PT6-p3_nnata (P)
Phoronis -muelleri (Ph)
Sigambra tentaculata (P)
Nephtys inc-l-s-a-T-PT-
W'mpellsca abdita (A)
Microp -is atra (E)
Ogyridi@'siimicola (D)
Cirriformia grandis (P)
A
y IT _elon_g-at_a___(_P)
s ch

(D
no A - Amphipoda B - Bivalvia E - Echinodermata 0 - Oligocha:eta
I @1
An - Anthozoa D - Decapoda (Crustacea) G - Gastropoda P - Polychaeta
Ph Phoronida
cn

ATTACHMENT 15-C (cont'd)
INVENTORY AND ZONATIO14 OF BENTHIC COMMUNITIES

b) DOMINANT MACROBENTHOS OF THE MESOHALINE ZONE

Species Largely Restricted to Sand Bottoms

Gernma gemma (B)
Mya arenaria (B)
Cyathura polita (I)
Leptocheirus plumulosus (A)
Eurytopic Species More Common or More Abundant on Sand 'Bottoms

Glycera dibranchiata (P)
Edotea triloba (1-T-
Heteromastus filiformis (P)
Macoma mitchelli--(BT-
Pseudeurythoe @a ucibranchiata (P)
Eteone lactea (P)

Species Largely Restricted to Mud Bottoms

Leucon americana (C)

Eurytopic Species More Common or More Abundant on Mud Bottoms

Nereis succinea (P)
Macoma balthica (B)
Scoloplos, fragilis (P)

Very Ubiquitous Species

Glycinde solitaria (P)
Paraprionospio (P)
Pectinaria goul
Peloscolex gabriellae (0)
Peloscolex heterochaetus (0)
Acteocina canaliculata (G)

A - Amphipod
B - Bivalvia.
C - Cumacea
G - Gastropoda
I - Isopoda
0 - Oligochaeta
P - Polychaeta

Appendix 15
C-2

-ATTACHMENT 15-C (cont'd)
INVENTORY AND ZONATION OF BENTHIC COMMUNITIES

c) DOMINANT MACROBENTHOS IN TIDAL FRESH WATERS

Oligochaeta
Dero digitata
Ilyodrilus templetoni
Limnodrilus cervix
Limnodrilus udekemanus
Peloscolex multisetosus

Bivalvia
Corbicula manilensis (James River)
Pisidium casertanum

Amphipoda
Gammarus fasciatus

,Insecta
Chaoborus punctipe nis
Coeloptanypus sp.
Procladius sp.
Hexagenia mingo

Appendix 15
C-3

ATTACHMENT 15-C (cont'd)
INVENTORY AND ZONATION OF BENTHIC COMMUNITIES

d) DOMINANT MACROSENTHOS OF THE OLIGOHALINE ZONE

Rhynchocoela
Unidentified white nemertean

Polychaeta
Scolecolepides viridis
Laeonereis culveri
Heteromastus filiformis

Oligochaeta
Peloscolex heterochaetus

Bivalvia
Congeria leucophaeta
Macoma balthica
Macoma mitchelli (=phenax)
Rangia cuneata

Isopoda
Chiridotea almyra
Cyathura polita
Edotea triloba

Amphipoda
Gammarus daiberi
LePtocheirus plumulosus

Insecta
Cryptochironomus fuivus

Appendix 15
C-4

ATTACHMENT 15-D
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

a. LETTER

Dear Colleague: May 1974

The Chesapeake Bay Hydraulic Model being constructed by the U. S. Army
Corps of Eagineers on Kent Island, Maryland, near the eastern end of the
Chesapeake Bay Bridge, promises to be very valuable to the engineer, water
resource planner, and scientist. It will provide a means of reproducing on
a manageable and measurable scale some of the physical phenomena that occur
in the Bay system, and will promote effective liaison among the agencies work-
ing in the Bay, help to reduce duplication of research, and assist public
understanding of the Bay and its best uses.

It should be emphasized that the hydraulic model, with inherent capacities
and limitations, is only another instrument of the scientist; there are questions
it cannot answer and it cannot interpret results. It can help define certain
physical effects such as thermal discharges and changes in salinity patterns
resulting from the diversion of fresh or salt water inflows, but the model will
not be able to define the effects of these environmental changes on the organisms
and biological conditions of the Bay. Biologists and others will have to inter-
pret the effects of these physical changes on the biota of the Bay and give the
planners and decision-makers an assessment of the full environmental impact.

The Baltimore District of the Corps, who is responsible for construction
of the model, has requested that members of the scientific co=unity identify
desired testing programs in order to promote greater and more effective uses
of the model. These uses do not necessarily have to be within your particular
area of expertise, but may encompass any phase involving model testing. After
reading the enclosed pamphlet, would you please complete the questionnaire and
return it in the prepaid envelope. Your help will be invaluable and appreciated.

Sincerely,
lr4-4:@ 01-
Hayes T./Pf @tze @yer
Chesapeake Bay Biota Project

Chesapeake Research Consortium, Incorporated
100 Vv%itehead Hall The Johns Hopkins University
The Johns Hopkins University University of Maryland
Baltimore, Maryland 21218 Smithsonian Institution Appendix 15
(301) 366-3300 Extension 766 Virginia Institute of Marine Science D-1

ATTACHKENT.15-D (cont'd)
QUESTIONNAIRE PACKAGE ANDIVRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

b. MODEL CAPABILITIES AND LIMITATIONS

1. To a degree, the limitations of tests will vary according
to the area and the depth of water being tested.

2. Tidal elevations in the model will be measured to 0.001
foot, which represents 0.10 foot in'the prototype.

3. Current velocities will be measured to 0.02 foot per
second (fps) in the model, corresponding to 0.2 fps in
the prototype. Verification procedures will probably
indicate that representative model velocities may vary
up-to a maximum of 20 percent from that in the prototype.

.4. Salinity in the model will be measured to the same accu-
racy as prototype measurements; horizontally, vertically,
and with respect to time.

5. Regarding temperature measurements, the model cannot be
used to predict prototype temperature; however, changes
in model temperatures can be measured to �.0.1 degrees.

6.- Sedimentation and shoaling tests will normally be conduc-
ted with a shoaling material simulant called gilsonite.
Test results are generally qualitative.

7. Dye concentrations in dispersion tests will be measured
to one part per billion. Previous model studies indicate
that the model can be used to predict the distribution of
concentration of conservative water quality constituents.
to an accuracy of about 20 percent.

8. Wind effects and prototype evaporation will not be repro-
duced since the model scale is distorted.

9. A semi-diurnal tidal cycle of 12.41 hours can be repro-
duced in the model to 7.45 minutes, and a year of record
in nature can be simulated in less than 4 days of contin-
uous operation.

Appendix 15
D-2

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
-CONCERNINq USES FOR THE BAY MODEL

.c. MODEL INFORMATION

Uses of the
Model
Hydraulic

The hydraulic model is one of the most versatile instruments available to the hydraulic
engineer and water resource planner, scientist, and engineer. In the Chesape ake Say Study the
hydraulic model will provide a means of reproducing to a manageable scale phenomena that
occur throughout this large and complex estuarine body. Undoubtedly, studies planned in
conjunction with the model will uncover problems of which serious students of the Say regime
are as yet unaware. As an instrument and physical display, the hydraulic model will be
unexcelled in its potential for the education of an Interested public in the scope and magnitude
of the problems and conflicts of use that can beset this water resource in the future. As an
operational focal point, it will promote more effective liaison aniong the agencies working in
1he Say waters, helping to reduce duplication of research and leading also to accelerated
spreading of knowledge among the interested parties of the public. 7:-
J
Research problems that will use the hydraulic model for their study Include:

1. Determine the salinity distribution within the Bay system and study the effects of
various factort on salt water intrusioni
2. Study the mechapics of estuary flushing,
3. Determine the effects of upstream Impoundments and basin diversions on salinity
distribution.' JJ
4
Study seasona I variations of salinity distribution,
.
Determine the effects of navigation projects and hannel geometry changes on currents t
5.
and salinities. A, I
circulation and upwolling current patterns of the Day
6. Develop better Information on the
waters.
IF. Determine preferred site locations of sewage treatment plants, Under water outfalls,
nuclear and fossil fuel power plants, and port facilities.
B. investigate existing waste disposal facilities, outfall locations, etc., for Improvement of
discharge conditions relative Jo the Say systern.
7
9. Investigate waste assimilation capacity of the Bay and its tributaries. (Time of passage
and waste dispersion tests. re-eeration coefficients.)
10. Study shoaling characteristics of the Bay end Its tributaries.
111. Locate ship handling problems, current actions peculiar to Say's waters that may be
dangerous to both recreational and commercial boating, and the effects of storm
conditions on the movement of water mosses.
,t> 12. Make a qualitative Appraisal and location of shore erosion problem areas.
13. Study the dispersion of oysier larvae by tides and currents to Arens suitable for culture.
14. Study the possible biological effects in conjunction with the dispersal of sift particles in
(D
U 0 certain methods of dredging disposal.
I @1 16. Study the possible influences of environmental conditions In the estuarine environment
CA) on the control of noxious weeds. jellyfish, and certain parasites.
Department of the Army aBaltimore District, Corps of Engineers

ATTACHMENT 15-D (cont'd)
QUES IONNAIRE PACKAGE AND WRITTEN RESPONSES
T
FROM BAY AREA SCIENTISTS
tj (D CONCEMING 'USES FOR THE BAY MODEL

General
c. MODEL INFORMATION (Contf'd) Model
Information Inforin-ution
0; _i@@
AUTHORITY: Section 312 of the River and Harbor Act of 1965 Type - Fixed Bed, Distorted
C
SCOPE: Complete investigation and study of water utilization and control of the Shel ter - Approximately 635,000 sq. ft.
Chesapeake Bay Basin including, but not limitad to, navigation, fisheries,
flood control, control of noxious weeds, water pollution, water quality Length 1080 ft
control, beach erosion, and recreation. Width ft.

Construction. operation, and maintenance of. a hydraulic model of the Area of Model:
Chesapeake Say Basin,
M::n Low Water 166.000 sq. ft
ates. M n High Water 184,000 sq. ft.
DESCRIPTION: Chesapeake Bay is the largest estuary in the United St
Length oi Bay - 195 miles +20 Contour 273,000 sq. ft.
Total paved 9 acres
Width of Say - 4 to 30 miles
Average depth of Bay - 28 feet Volume of Water: 0
Water surface area (Maryland & Virginia) - 4,300 square miles
Mean Low Water 60,000 cu. ft.
Chesapeake Say Drainage Basin - 64.170 square miles Ordinary Tide 4,000 cu. I t.
Tidal Shoreline - 7,300 miles Spring Tide 5,000 cu. ft.
Deepest point in Say - 174 feet near Bloody Point Length of ternplets 130,000 ft. 126 Q-
miles) used in model construction.
Fed by nine major river streams:
WaterSupplySump 85,000cu.ft. A-
Choptank Patuxent Rappahannock -
James Pocomoke Susquehanna Pipe Diameters for supply-return 24 to
Nanticoke Potomac York 36in.

Approximately 50% of the total fresh water entering the Say comes from Metal strips embedded in model permit
the Susquehanna River. 'adjustment of frictional resistance to
accurately reproduce the bay's tides,
nts, and salinities.
curre
APPROXIMATE MODEL LIMITS

CONVERS.ION OF MODEL DATA TO PROTOTYPE REOUIREMENTS

This site, the former Model Factor Prototyp)
eastern terminus of the
Sandy Point - Matapeake I ft. Depth 100 ft.
Ferry, will be developed as AA1.A
I ft. Length or width 1,000 ft.
j
10 slope I
Model Comple)
I cu. ft, Volume 100,000,000 cu. It.
the Chesapeake Day
which
will include on@ of the I cu. ft, per,,.. Discharge 1.000,000 cu. ft. per see.
world's largest working I ft. per sec, Velocity 10 ft. rer eec. Vi
scale models of an estuary, 7.45 minute$ Time 12 howl end 25 minutes 0
1 Salinity I

ATTACHMENT 15-.D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES.
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THEZAY MODEL'

d. SAMPLE QUESTIONNAIRE

1. Can the Chesapeake Bay Hydraulic Model be used in any
research in which you are presently involved? If yes,
please explain.

jr-

2. What biological appl ications or tests can you foresee for
the Chesapeake Bay Model?

3. Have you had previous experience with another hydraulic
model P testing some biological parameter? If so, briefly
describe.

4. Do you have any data of unique environmental or biological
conditions which have occurred in the Chesapeake Bay or
tributaries which you think might be used in future re-
search involving the model?

5. Do you work with, or are you aware of, any mathematical
biological techniques that can be utilized with hydraulic
model studies? If so, please specify.

Appendix 15
D-5

ATTACHMENT 15-D.(-cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

e. SUMMATION TO REPLIES TO QUESTIONNAIRE

A. CAN THE CHESAPEAKE BAY HYDRAULIC MODEL BE USED IN ANY
RESEARCH IN WHICH YOU ARE PRESENTLY INVOLVED? IF YES,
PLEASE EXPLAIN.

1. Distribution of planktonic organisms with respect to
salinity gradients and tidal cycles.

2. Modeling and predicting the advection of pollutants,
especially nutrients.

3. Qualitative indications of sediment dispersion at
mouths of rivers.

4. Higher-density, nutrient and trace element enriched
water accumulates in anoxic zone of central Bay during
summer. In what way does this water mix into upper
Bay water and into lateral tributaries? Does this
water act as a nutrient source for late summer plank-
ton blooms (mahogany water) in upper Bay?

5. Transport mechanics of menhaden larvae from the
Atlantic Ocean to the low-salinity tributaries of
Chesapeake Bay.
6. To assist in understanding how certain locations are
hydrodynamically prone to infestation of sea nettles.
Also the production and contribution of nursery areas
of many organisms may be enlightened through this
facility.

7. Salinity ranges throughout Bay and under various
flushing conditions. Could help explain fish and
zooplankton distribution.

8. Estuarine flushing: Possibly residual times of toxic
organic and inorganic compounds.

9. Studies of tidal flushing and salinity gradients will
reveal that physical parameters of a system are as
important as any biological ones.

10. Effects of sewage discharge and power plant discharge
on aquatic organisms.

11. Teaching students about hydraulic modeling.

Appendix 15
D-6

ATTACMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE.AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

12. Study of current direction and velocity relative to
geometric changes, i.e., jetties - manmade structures.
Study of tidal surges - flooding.
Study of nearshore sediment transport.

13. For studies on dispersal of juvenile blue crabs, it
would be helpful to know the current patterns moving
up the Bay, at depth, between June and October.
Halocline patterns would also be useful.

14. The Chesapeake Bay Hydraulic Model could be of use
to us in helping to determine which areas are most
likely to need frequent biological surveys because
of changing environmental conditions. An example
of this would be oyster settings, clam settings,
and fish migration patterns which can be greatly
aff&cted by both environmental and manmade changes
in the topography of the Chesapeake Bay and its
tributaries.

15. We feel the model may bear on our interest in the
persistence of plankton patches in river systems
and the main Bay-stem.

16. Many possible uses by the State of Virginia as a
regulatory agency involving permits for discharges.

17. Remote possibility to study the survival and disper-
sion of phytoplankton species that are natural to or
introduced into the model.

18. The model, with some modifications, will be very
useful in shoaling studies.

19. Physical relationships to magnitudes of specific
populations.

20. Sediment movement; stratified flows; shore erosion.

2-1. In a saline marsh-ecology project conducted in St.
Mark's Wildlife Preserve, Florida. One of the areas
of investigation is loss of nutrients and detritus
to the estuary and quantification of energy movement.
Such a model as you describe would be very useful in
determining nutrient and detrital movement per tidal
cycles. The rate of washing out dyes or tagged detri-
tus could be followed.

X 22. The Model can be used to site sewage-treatment plant
outfalls (i.e., the present siting activity).

Appendix 15
D-7

ATTACM11ENT 15-D (cont'd)
QMTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THEBAY MODEL

23. If model is sufficiently sophisticated,, it may be
used to predict the dispersion and advection of
pollutants from a specified source.

24. 1 am working with the distribution and abundance of
canvasba@cks and other waterfowl in the Bay in rela-
tion to the flora and fauna of the Bay. If the model
can be used to predict the changes and abundance of
the flora and fauna, I should be able to make a cor-
relation with the waterfowl.

25. We are presently involved with shellfish sanitation
work on the estuaries leading into the larger rivers.
We are interested in how these larger rivers (Potomac,
Rappahannock, e.g.) affect flushing characteristics
of the sub-estuarine (e.g., Yeocomico R., Nomini R.,
etc.).

26. The Hydraulic Model should be useful in connection
with the oyster hatchery being built in the Bay area.
The determination of the effect of multiple-layer
oyster-growing trays in the rivers and bays could
be ascertained.

27. Studies of Water Supply Problems.

a. Effects of embayments, impoundments, and other
flow alterations on supply patterns.

b. Consequences of increasing consumptive-use pat-
terns such as possible fresh-water shortages.

Studies of Water Quality Problems.

a. Determination of area and degree of impact of
certain urban and/or industrial wastes and runoff.

b. Patterns of suburban and/or agricultural runoff
and dispersion.

c. Waste-water control and reclamation.

d. Effects of wetlands on water quality.

e. Areas affected by sewage treatment plant effluents.,

f. Dredging and overboard spoil disposal problems.

Conservation of Fish and Wildlife Resources

a. Mechanics of input, transport, and dispersal of
materials toxic to Chesapeake Bay organisms.

Appendix 15
D-8

ATTAC11MENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND '-iRITTEN RESPONSES
FRON BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

b. Dispersal patterns of regulated food contaminants
throughout the habitats of commercially utilized
species.

c. Boundaries and potential effects of basic habitat
alterations such as salinity displacements.

d. Definition of environmental alterations induced
by natural phenomena such as hurricanes and
tropical storms. I .

e. Tides, currents, and dispersal patterns associ-
ated with fish mortalities.

Studies of Erosion and Sedimentation.

a. Patterns of natural erosion and sedimentation in
estuarine waters.

b. Effects of specific human activities on sedimen-
tation rates and patterns.

c. Evaluation of methods of stabilizing shorelines
and protecting tributaries from excessive
sedimentation.

Recreation.

a. Site capacity studies for marinas, fishing piers,
and other recreational facilities.

b. Effects on established recreational areas such as
beaches by other activities such as dredging and
spoil disposal.

c. Studies of the effects of municipal, industrial,,
and agricultural activities on the habitats of
,sports-harvested species.

Feasibility and Impact Studies for PropoAed Projects.

a. Power plant siting studies.

b. Sewage treatment plant siting studies.

c. Waste and spoil disposal siting studies.

d. Any other proposed project involving potential
physiochemical alteration of the environment.

28. We are interested in bacteria associated with sus-
pended particulate matter and with sediment.
Therefore, the effects of current, salinity, and

Appendix 15
D-9

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BkY MODEL

temperature in affecting distribution of particulate
matter., hence, bacteria would be of interest to us.

29. To study changes in benthic invertebrate population
an"d community structure under altered environmental
conditions.

30. Fish movements, effects of alterations upon fish
avoidance or attractions. General zones of salinity
in which fish might be encountered.

31. Studies of water motion and mixing in Bay using
radioactive cesium fallout as a tracer. Model will
be valuable to test tracer method.

32. Scaled-down nutrient enrichment studies. Sedimenta-
tion studies. Dispersion studies.

33. Entrainment of biota at power plant sites.

Appendix 15
D-10

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WTtITTEN RESPONSES
FROM BAY AREA SCIHNTISTS
CONCERNING TISES FOR THr BAY !@07`L

B. WHAT BIOLOGICAL APPLICATIONS OR TESTS CAN YOU FORESEE FOR
THE CHESAPEAKE BAY MODEL:

1. Plankton distributions

2. Biological applications must be inferred from rela-
tively few physicochemical parameters. These can,
howeverk be used to identify geographically the
various hydrographic regimes,,which may require
different management procedures. More biological
information would be indicated.

3. This model could be useful in determining expected
salinities and temperatures along Chesapcake Bay,
which in turn could be used to assess the impact of
power plants and other industrial development along
the Bay.

4. Gross indications of dispersion of larval stages of
shellfish.

5. Physical models may be very important in the testing
and managerial implementation of biological models.
This importance stems from the use of hydraulic models
to predict the spatial and temporal distributions of
nutrient materials, toxic chemical species, suspended
sedimentV currents, and other factors which may be
inputs to biological response models. Hence, even
though biological phenomena cannot be directly con-
sidered using physical models, these models may be
required for the real worlds of application of math-
ematical models to biological processes.

6. With proper light-energy and source-water, would it
be possible to reconstruct the late summer hydro-
graphic conditions and attempt to see effects on
algae growth?

7. Effects of long-term re equivalent to 10-20 years of
perhaps Melon Kovetch cycle studies.

8. Current transport mechanics for menhaden, other fishes
and invertebrate larvae.
Distribution of detritus, plankton and other nutrients.
Sedimentation and cycling of metallic ions.

9. Oyster spawning success - seed areas - characterize
fromknown and look for similarities. Use statistical
reliability criteria.

10. Prediction of extreme salinity conditions under peri-
ods of maximum and minimum discharge.

Appendix 15
D-11

ATTACHMENT 15-D (cont'd)
QUESTIO14NAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL-
11. Analysis of the fate of waste plumes under varying
conditions so that a real extent of discharges and
concentrations can be estimated. Biologists can
then use this information on the planning of lab-
oratory experiments to determine the effects of
living systems.

12. 1 would like to know the relative importance or lack
of importance of the tributaries such as the Anacostia
River to the water-flow down this section of the
Potomac. I would also like to know the proportional
roles played by man-made effluents - sewage plants
and heated power plants.

13. Evaluate impact of STP outfalls on shellfish growing
areas.

14. Life cycle studies.

15. Effect of power plants, pesticide programs, and indus-
trial development. Transport of fish larvae within
Bay. Effect of residential development and resulting
pollution. Recruitment studies involving commercially
important crustaceans.

16. Changes in distribution of fish and invertebrates
related to the impact of power plants and sewage
discharge.

17. Movement of fish eggs due to circulation of water in
the Bay.

18. Distribution and dilution effects on microbial pol-
lutants as related to shellfish resources; public
health aspects of waterborne toxicants and viable,
disease agents.

19. Movement of pollutant chemicals in water and sediment,
intoV within, and out of the estuarine model.

20. If changes in salinity, temperature, turbidity, and
silt deposition occur to an extent whereby marsh,
swamp and other wetland vegetation is affected, or
if pollution deposition occurs to such an extent,
then certainly any research involving marsh and/or
aquatic vegetation would benefit from knowledge of
indicated changes as predicted by the model. How
much change would be required and whether or not
such a degree of change would be within the model's
capability would have to be determined. Effects of
erosion on wetlands. Transport of detritus from
marshes throughout the Bay - greatest and/or most
valuable source of productivity and sinks and trans-
port. Effects of ice formation and scouring.

Appendix 15
D-12

ATTACHMENT 15--D (cont'd)
QUESTIONNAIRE PACKAGE AND 14RITTEII RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MOM?.T,

21. The Chesapeake Bay Model could provide mass transfers
of materialsl species, etc., among sections of the
Bay as inputs to "Seasonal", or quasi-steady state,
ecosystem models.

22. Helping to determine what effects weather changes,
etc... can have on oyster settings, clam settings,
clam/oyster spawnings, etc. An example of this
would be the effects of the changing of a shoreline
pattern by building a bulkhead, etc.

23. Using dye innocula or, with suitable illumination, an
actual phytoplankton introduction which is subse-
quently sampled over time.

6
24. Thermal (Nuclear Power Plant Discharges).

25. Erosion and shoaling in beds of oysters, clams, eel-
grass, and marshland at water's edge. Effects of
unusual storms or seasons on salinity and silt lo,-.d.
Rate of transport for pollutants.

26. Hydrodynamic distribution of pollutants,from point-
sources through dye and chemical studies.

27. Effects of dispersed wastes as related to aquatic
life.

28. The dispersion and rate of degradation of various
pollutants.

29. The model can be used to determine some circulation
change (mostly local) due to natural abnormal stages
(flood or storm surges) or pollutant movements. Then
the results can be applied to ecosystems as input
functions. Direct biological simulation (for in-
stance dispersion of larvae, etc.) is impossible and
the results may be misleading.

30. Flushing rates and relations between net flows, in
and out, surface and bottom and precipitation rates
as they affect change in biological recruitment of
certain species.

31. Investigations of pollution and alteration of estu-
arine systems.

32. Influence of organisms on sedimentation (by deduction).

33. Environmental pollution.
Plankton studies.
Chemical and-physical, ocean or estuarine studies.
Sedimentation.

A]@pendix 15
D-13

ATTACHMENT 15-1) (cont@(i)
QUESTIONNAIRE PACKAGE ANT) WRITTEN RESPONSES
FROM BAY AREA SCIENTIST!)
CONCERNING UISES FOR THE BAY Vnnf?.T.
Vegetative experimentation.
Controlled radiation.

34. Mixing at river junctions and in vicinity of wetlands.
Movement through defined channels in wetland areas.

35. 1 think the model should increase its biological capa-
bility especially in regard to determining the cause
of the decline of vegetation.

36. We need to know dilution, flushing and time of travel
in order to understand coliform and fecal coliform.
patterns throughout the Bay.

37. Sewage effluent tracing.
Bacterial die-off.

38. Comparison of distribution of hypothetically totally
passive plankton organisms with actual distribution,
in a study of intrinsic controls over dispersion.

39. Distribution and setting of oyster larvae.
Intrusion of oyster drills with dredging and increased
salinities.
Intrusion of MSX and other disease organisms.
Modifications of spawning grounds of fishes - and
larval distributions.

40. By determining current patterns in the Bay, it may be
possible to predict and lessen the impact of toxic
pollutant discharges on fisheries.

41. Planktonic larval distribution and dispersal.
Population control by salinity, temperature, etc.
Population dispersal.

42. The ability to define and project certain significant
physical parameters of the physico-chemical environ-
ment allows a more refined focusing of bioassay enter-
E
rises, endowing the model with application in the
iological realm. It is appropriate to state that
this type of relationship exists as a significant
factor in most areas of biological investigation
and given man's tendencies to constantly alter the
existing environment, the model should be of con-
siderable value to future investigations.

43. Biological applications would be to determine the
distribution of bacteria and viruses in the Chesapeake
Bay as affected by current, turbidity, suspended mat- AL
ter, etc.

Appendix 15
D-14

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE ANID WRITTEN RESPONSES
FROM BAY AREA 3CIENTISTS
CONCERNING USES FOI THE BAY MODEL

44. Document herbicide and pesticide run-off to the Bay
and correlate the oyster reproduction with its flow
pattern. Do same for heavily chlorinated sewage
effluents.

45. Study changes in benthic invertebrate populations
and community structure under altered environmental
conditions and studies of production (yield) under
different conditions.

46. Identification of probable sinks for heavy metals and
other toxins introduced in particulate form. Coupled
with data on temperature, turbulence, salinity, and
water depth, predictions should be feasible of the
probability of remobilization of trace toxins by
Tesuspension.

47. Thermal model studies. Electric facilities.

48. Test to check the distribution by currents of repro-
ductive propagules of plants.

49. Widely varied uses - in problems involving circulation.

50. Predict the movement of noxious effluents with respect
to the location of commercial shellfisheries.

51. Distribution of sediment..pollutants, heat and nutri-
ents from point sources with continuous, instantaneous,
or periodic releases.

52. Possibly bioassay application for certain chemicals
such as chlorine, chloraminesp- cyanides, etc.
Phytoplankton distribution studies with respect to
wind and tides.
Schooling behavior of fish (young menhaden) and their
effects on the water quality with respect to uptake
of algae and waste excretion along with respiratory
utilization of oxygen.

53. Estimates of entrainments for multi-site power plant
installation in the northern end of the Bay.

Appendix 15
D-15

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTESTS
CONCERNING USES FOR THE BAY MODEL

C. HAVE YOU HAD PREVIOUS EXPERIENCE WITH ANOTHER HYDRAULIC
MODEL., TESTING SOME BIOLOGICAL-PARAMETER? IFSOP BRIEFLY
DESCRIBE.

1. Mathematical as opposed to physical modeling has been
succe.ssfully used for pollution abatement on the
Potomac Estuary, especially with regard to dissolved
oxygen deficiencies and eutrophication parameters.

2. The use of the James River Model owned by the Virginia
Institute of Marine Science and the U. S. Army Corps
of Engineers was recently considered for projection of
the movement of oil spills and refinery waste products
in the Hampton Roads area of the James River. This
information was to be utilized to assess potential
impacts on the estuarine biotic community. However,
due to alterations in plant design, these experiments
will no longer be required.

3. Water Experimental Station Model of C & D Canal.

4. 1 have heard about the hydraulic model being used on
the James River which has been for the most part very
useful to the biologists in Virginia.

S. Models of Hudson Estuary and New York Bight.

6. A physical model developed by the Alden Laboratories
was used to predict the temperature regime in the
vicinity of a power plant using once-through cooling.
Our company was involved in analyzing the biological
effects of the discharge.

7. James River Hydraulic Model - oyster larvae distribu-
tion study.

8. We are familiar with the Narragansett Bay Model used
a few years ago to predict coliform., D. 0. patterns.

9. Salem Church Dam,proposal. Distribution zone (nursery)
for young-of-the-year alosids, and striped bass., Other
marine fish.

Appendix 15
D@-16

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING ITSES POR THE BAY MODET,

D. DO YOU HAVE ANY DATA OF UNIQUE ENVIRONMENTAL OR BIOLOGICAL
CONDITIONS WHICH HAVE OCCURRED IN THE CHESAPEAKE BAY OR
TRIBUTARIES WHICH YOU THINK MIGHT BE USED IN FUTURE RE-
SEARCH INVOLVING THE MODEL?

1. Plankton data as a result of hurricane AGNES on the
lower Bay. York River distributions.

2. We have extensive data holdings on upper Chesapeake
Bay and some tributaries including the Potomac
estuary. Monthly observations of water quality
parameters, especially nutrients, are available.

3. Rice Division (Nus Corporation) is currently under-
taking a study of chemical and biological water
quality in the Hampton Roads vilcinity of the James
River estuary. These data may be utilized at some
future date in conjunction with model research and/or
model development.

4. Open-water metabolic estimates from Rhode and West
Rivers, 1970 through 1974.

S. Over 10 years of oyster setting records for Tred Avon
River- Broad Creek, and Harris Creek. Also salinity
and t;mperature (weekly and some daily) for Tred Avon
River.

6. 1 have biological data on Potomac River from Chain
Bridge to Piscataway Creek from 1970 to 1971 and 1973
to 1974. Also I have plankton data at 10-mile sites
to Pt. Lookout. Presently, I have an 0. W. R. P.
grant with the Dept. of Interior to study the aufwuchs
microcosms collected on mid-river buoy/floats,and Blue
Plains sewage final sedimentation tanks.

7. Limited *bacteriological data in Virginia tributaries
collected in our efforts to open shellfish areas
closed as a result of hurricane AGNES.

8. Tide recording in Spa Creek and noted frequencies
higher than for a normal tide cycle. We think they
represent seiches.

9. 1 have some data on the effects of declining salinity
and of sedimentation upon the inshore macroinverte-
brate fauna.

10. Salinity fluctuations over past years that may.relate
to spread of disease organisms such as MSX, Paramoeba,
etc.

11. Elizabeth, Back River, etc., from present RANN Contract.

Appendix 15
D-17

ATTACHMENT 1-5-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THP BAY MODEL
12. Much published data concerning waterfowl popul *ations:
abundance, distribution, sex ratios, etc. Also much
unpublished data concerning invertebrate sampling in
the Bay and extensive weights and measurements of
Rangia in Potomac and Baltimore Harbor.

13. Limited data on coliform., fecal coliform, and fecal
streptococcus.

14. Hydrographic nutrient and zooplankton data before,
during, and after flooding from tropical storm AGNES
lower Chesapeake Bay.

15. Worked on "Operation York River" and "Over-Ride" after
hurricane CAMILE hit Virginia. Measured physical
parameters with other people from VIMS.

16. The broad scope and constant nature of the investiga-
tive programs of the Department of Natural Resources
has contributed to compilation of a large and compre-
hensive data band which includes data on most environ-
mental or biological conditions in.recent years.

17. We have data concerning bacteria associated with
particulate matter, and the influence of salinity
and current on the distribution of these bacteria.
(U. of Md. Dept. of Microbiology).

18. Have information on the distribution and abundance of
aquatic.grass beds.

19. Tracer work since 1968 using Cesium, including AGNES
data.

20. We find the upper ends of most tidal embayments or
creeks to be conducive to eutrophication as a result
of the various undefined physical phenomena of flow,
sedimentation rates, etc. It would be nice to be
able to quantify some of these effects.

Appendix 15
D-18

ATTACHMENT 15-D (c,)nt'U-J
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL
E. DO YOU WORK WITH, OR ARE YOU AWARE OF., ANY MATHEMATICAL
BIOLOGICAL TECHNIQUES THAT CAN BE UTILIZED WITH HYDRAULIC
MODEL STUDIES? IF SO, PLEASE SPECIFY.

1. 1 believe that selected studies can be described and
tested.

2. Possibly bacterial densities in tidewater can be
related to runoff and flow conditions, but we have
no hard data pertinent.

3. My doctoral research project is concerned with the
mathematical modeling of biological response. At
present, a model of primary productivity has been
calibrated and tested. A conceptual model of aquatic
food web interactions has been formulated and calibra-
tion efforts have been initiated. The dissertation
paper is entitled "A mathematical model of eutrophi-
cation in Lake Mead.1f

4. Only general loading, productivity models with phyto-
plankton and, to much lesser extent, bacterioplankton
and bacteriobenthos.

5. The Annapolis Field Station of E.P.A. has done much
modeling work.

6. Lehigh University has computer program for the Behrens
Natural Resource Utilization Model.

7. Write College of Fisheries, University of Washington,
concerning Cedar River - Lake Washington study which
looked at this habitat in a systems analysis manner.

8. The Delaware Estuary Water Quality Model of the
O'Connor - Thomann (Manhattan College) variety and
the hydrodynamic model of D. Harleman and his col-
leagues at M.I.T. See Tracor, Inc., Estuarine
Modeling: "An Assessment", E. P. A. (U. S. Govern-
ment Printing Office, Washington, D. C., Cpts. 2, 3,
and 5).

9. Analysis of variance for production data which permits
assessing overtime, characteristic differences in
phytoplankton performance with position in the.Bay.

10. See study of Jamaica Bay.

11. Best way may be to develop numerical models based on
physical data obtained from model experiments.
12. Hybrid computation involving logic gates and track
and store units.

Appendix 15
D-19

ATTACHMENT 15-D (cont'd)
QUESTIONNAIRE PACKAGE AND WRITTEN RESPONSES
FROM BAY AREA SCIENTISTS
CONCERNING USES FOR THE BAY MODEL

13. Systems analysis using differential equations. Use
the model for scalinor.

14. There are a number of computer models (e.g., Univ.
of Oregon, Water Resources Engineers, E.P.A.) that
simulate estuary conditions (temperature, salinity,
sediment flow., etc.) which influence biological con-
ditions: These models could-be (and should be)
tested under laboratory control in the'Bay Model. 1P

15. 1 am aware of some math technique.s that might perhaps
be applied to hydraulic model studies, i.e., statis-
tics, fluid mechanics, similarity conditions, etc.

16. Attached is a list of references we have considered
in some of our Work. (References for Outfall Studies,
see Appendix I.)

17. The Department of Natural Resources is presently con-
tracting for two modeling studies of the Chesapeake
Bay. Both studies are transport models, one involving
the transport of sediments, and the other dealing with
dissolved solids. While neither study is focused on
the biological, both can be applied to problems in-
volving transport of biologically significant mate-
rialsP such as toxicants.

18. Larval fish dispersal may follow some dispersion
tendency such as salinity. Test homing and voluntary
migration versus random involuntary dispersals.

19.1 Use of bottom dwellers, such as clams, as indicators
of tracer and salt concentrations and thus water move-
ment and mixing.

20. Striped bass spawn-entrainment computer models.

Amendix 15
D-20

Ell