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Nor -lNvt:o IGATION OF AMERICAN SHAD IN THE cm SAPEAKE'BAY' 0.,31-STALZONE INFORNIATION CENTER 1980 c DALE R..WEINRICH MARY ELLEN DORE W..R. CARTER I CECIL COUNTY Conowingo Dam (;y Susquehanna River Northe t RiveT HARFORD COUNTY eA- T N L QL 'berdeen Proving Tur lilt Grou 638 C64 158 1984 Tidewater Administration MARYLAND DEPARTMENT OF NATURAL RESOURCES SEPT-c-MBE:-HI UNITED STATES DEPARTMENT OF INTERIOR FISH AND WILDLIFE SERVICE FEDERAL AID REPORT State: MARYLAND Project No.: F-37-R Project Title: Investigation of American shad in the Upper Chesapeake Bay Status: Annual Report Period Covered: January 1, 1980 to December 31, 1980 Prepared By: Dale R. Weinrich, Project Leader Date: Sept.2, 1981 Mary Ellen Dore, Staff Biologist W. R. Carter, III, Program Leader Approved By: Date: 9/2/81 William P. Jensen, Director Tidal Fisheries Division, Maryland Tidewater Administration Date: 9/2/81 Howard J. King, Federal Aid Coordinator Tidal Fisheries Division, Maryland Tidewater Administration Property of CSC Library U.S. DEPARTMENT OF COMMERCE NOAA COASTAL SERVICE CENTER 2234 SOUTH H0BSON AVENUE CHARLESTON, SC 29405-2413 L ABSTRACT During 1980, adult American shad (Alosa sapidissima) were collected at the head-of-the-Chesapeake Bay with various commercial fishing gears. Of the 399 fish observed, 147 were successfully tagged and released. Based on 13 recaptures, a population estimate of 2,675 American shad (UL=4,740, LL=1,607 @ 95% CL) was made utilizing Chapman's modification of the Petersen formula. Analysis of length, w eight, sex ratios, age; and spawning history indicated that the 1979 and 1980 head-of-the-Bay shad runs were similar and could be characterized as a population supported by two remnant age classes with approximately 11% repeat spawners. Major differences were noted with other east coast shad stocks particularly the stable and increasing runs on the Delaware and Connecticut Rivers. Only one American shad was reported captured during the 1980 Susquehanna River sport fishing survey. 1980 sport catches for other clupeid species were also well below previous reported levels. White perch, channel catfish, and striped bass made up 81% of the estimated sport angling harvest in 1980. No young-of- the-year American shad were cap tured by haul seine or otter trawl from 10 upper Chesapeake Bay sampling stations in 1980. Severe declines in numbers and standing crop for all Alosa species from the late 1960's through 1980 in the Susquehanna estuary was noted. An American shad literature review was initiated to broaden Maryland's biological and management data base. Comparison of this state's present situation with the successful management.practices of other areas was. undertaken in hopes of restoring the severely depleted shad stocks to levels allowing for the perpetuation of the species and eventual consumptive use of the resource. WW ACKNOWLEDGEMENTS 11 We would like to acknowledge the assistance of Bill Hogans and Tim Sughrue who provided tireless field help under arduous conditions. Thanks are due those people who also helped as creel lerks; John Foster, Mike Burch, Howard King, Rudy Lukacovic, Joan Williams, and Bob Lunsford. We extend our gratitude to c Captains Frank and Henry Pratt, Howard Sexton, and Alvin Price and their respective crews in helping us obtain adult American shad for tagging. Special thanks are due Nick Carter, Harley Speir, and Steve Early for their field help and acute editorial assistance. le also thank Rose Safford for typing the manuscript. MN iv TABLE OF CONTENTS Page Introduction 1 Job I. Tagging And Population Estimation 2 Job II. Population Characterization 16 Job III. Creel Census 37 Job IV. Juvenile Recruitment Survey 50 Job V. Literature Review And Survey. 112 Conclusions --nd Recommendations 119 Literature Cited 123 LIST OF TABLES 1. Capture-recapture dates, locations, and gear types 11 for thirteen recaptures of tagged American shad during 1980. 2. Comparison.of total catch, number tagged, number 12 lost, and % net mortality by location and gear type for American shad captured in the Susquehanna River, Susquehanna Flats, and Northeast River during 1980. 3. Population estimate of adult American shad utilizing 13 the Susquehanna River, Susquehanna Flats, and Northeast River for 1980. 4. Age composition of Susqueh anna River American shad 24 collected by the Conowingo Dam Fish Lift and by sport anglers from 1972 through 1979. 5. Mean fork length (mm), mean weight (kg), and length 26 and weight ranges by sex and age class for American shad collected from the Susquehanna drainage during 1979 and 1980 by various gear types. 6.. Age frequency,.number, and percent repeat spawners 28 by sex for American shad collected from the Susquehanna drainage during 1979 and 1980 by various gear types. V Page 7. Age frequency, number, and percent repeat spawners 30 by sex for American shad collected from selected east coast rivers during 1978 and 1979 by various gear types. 8. Mean fork length (cm) and length ranges'by sex 34 and age classes for American shad collected from the Connecticut and Delaware Rivers during 1979. 9. Access points and comparison of associated sampling 42 probabilities for the lower Susquehanna River Creel Surveys, 1970, 1979, and 1980. 10. Time blocks, time units, and associated sampling 43 probabilities for creel census of the lower Susquehanna River, May-June, 1980. 11. Comparison and characterization of data collected 44 from the 1970-, 1979, and 1980 Susquehanna River Sport Fishing Surveys. 12. Catch per angler hour for selected species caught 45 during the 1970, 1979, and 1980 Susquehanna River Sport Fishing Surveys. 13. Comparison of the species composition and harvest 46 of finfish caught by sport anglers during the 1979 and 1980 Susquehanna River Sport Fishing Surveys. 14. Sampling periods during the 1980 Juvenile Recruitment 63 Survey. 15. Station numbers, names, locations, and mode of 64 sampling during the 1980 Juvenile Recruitment Survey. 16. Trawl station number, name, location, and compass 65 bearings during the 1980 Juvenile Recruitment Survey. 17. Number of seine hauls and trawl runs by period and 66 site during the 1980 Juvenile Recruitment Survey. 18. Number of hauls and area swept by haul seine' for 67 each sampling period during the 1980 Juvenile Recruitment Survey. 19. Area swept by otter trawl for each sampling period 68 by site during the 1980 Juvenile Recruitment Survey. 20. Area swept by haul seine and otter trawl, number 69 of hauls taken and trawl runs completed, and total area swept during the 1980 Juvenile Recruitment Survey. 21. Species caught during the 1980 Juvenile Recruitment 70 Survey. vi Page 22. Species and numbers of individual finfish collected 72 by haul seine during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 23. Species and numbers of individual finfish collected 74 by otter trawl during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 24. Species and number of individual finfish collected 76 by haul seine at ten sampling stations from 23 June through 1.10ctober for the 1980 Juvenile Recruitment Survey. 25. Species and number of individual finfish collected 78 by otter trawl at six sampling stations from 23 June thiough 31 October for the 1980 Juvenile Recruitment Survey. 26. Species and weight (grams) of finfish collected by. 80 haul seine during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 27. Species and weight (grams) of finfish collected by 82 otter trawl during t(sn@- sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 28. Species and weight (grams) of finfish collected by 84 haul seine at ten sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 29. Species and weight (grams) of finfish collected by 86 otter trawl at six sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. 30. Total numbers collected, total area swept, and 88 standing crop in numbers per hectare for all species combined for each gear type by sampling period during the 1980 Juvenile Recruitment Survey. 31. Total area swept, total weight of species collected, 89 and standing crop in kilograms per hectare for all species combined for each gear type by period, during the 1980 Juvenile Recruitment Survey. 32., Total numbers collected, total area swept, and 90 standing crop in numbers per hectare for al.1 species combined for each gear type by station during the 1980 Juvenile Recruitment Survey. vii F Page 33. Total area swept, total weight of species collected, 91 and standing crop in kilograms per hectare for all species combined for each gear type by station r during the 1980 Juvenile Recruitment Survey. 34. Numbers caught and catch-per-unit-effort (CPUE) 92 by sampling period, total catch, and total CPUE for young-of-the-year Alosa &estivalis, Alosa IP pseudoharengus, Morone-!i-a-xat s, and Morone americana for haul seine and otter trawl during the 1980 Juvenile Recruitment Survey. 35. Numbers caught and catch-per-unit-effort (CPUE) 93 by sampling station, total catch, and total CPUE for young-of-the-year Alosa aestivalis, Alosa ppeudoharengus, Morone saxatilis, and Morone americana by hau e and otter trawl during the 1980 Juvenile Recruitment Survey. 36. Standing crop as numbers per hectare for young- .94 of-the-year Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone americana collected by haul seine and otter trawl in each sampling period during the 1980 Juvenile Recruitment Survey. 37. Standing crop as numbers per hectare for young- 95 of-the-year Alosa aestivalis, Alosa pseudoharengus,@ Morone saxatilis, and Morone americana collected by haul seine and otter trawl at each sampling station during the 1980 Juvenile Recruitment Survey. 38. Reported commercial catch as pounds caught of 96 American shad and alewife/blueback herring combined from the Susquehanna River, Susquehanna Flats, and the Northeast River from 1968 through 1980.- 39. Species and number of individual finfish collected 97 by haul seine during six sampling periods for the 1979 Juvenile Recruitment Survey. 40. Species and number of individual finfish collected 99 by haul seine at ten sampling stations during the 1979 Juvenile Recruitment Survey. t 41. Species and weight (grams) of finfish 'collected by 101 haul seine during six sampling periods for the 1979 Juvenile Recruitment.Survey. t 42. Species and weight (grams) of finfish collected by 103 haul seine at ten sampling stations during the 1979 Juvenile Recruitment Survey. IP VII.L Page 43. Total catch and catch per haul by haul seine by 104 sampling period for young-of-the-year Alosa sapidissima, Alosa aestivalis, Alosa pseudo arengust Morone saxatilis, and Morone americana. during the 1979 Juvenile Recruitment Survey. 44. Total catch and catch per haul by sampling station 106 for young-of-the-year Alosa sapidissima,'Alosa aestivalis, Alosa pseudoha-rengus, Morone'saxatilis, and Morone americana during the 1979 JuveRi-le Recru.i.tment Survey. 45. Comparison of the population density (numbers per 107 hectare) of young-of-the-year American shad, and blueback herring captured by alewife herring, haul sei-e and otter trawl from the Susquehanna drainage during 1968, 1969, and 1980. 46. Reported commercial catch of American shad from all 118 waters in Florida, Georgia, South Carolina, North Carolina, Virginia, Maryland, and the DelawAre, Hud�on, ahd Connecticut Rivers from 1962 through 1980. LIST OF FIGURES I. Gear and locations utilized in tagging adult 14 American shad during 1980. W4 Ii. Numbers of American shad caught for tagging by all 15 gear types and by date from the Susquehanna River, Susquehanna Flats, and Northeast River during 1980. III. Length frequency distribution for male American 35 shad collected from the Susquehanna System in 1980. IV. Length frequency distribution for female American 36 shad collected from the Susquehanna System in 1980. V. Interview sites for the 1980 Susquehanna River 47 Sport Fishing Survey. Vi. Interview form for the 1980 Susquehanna River Sport 48 Fishing Survey. I VII. Survey stations for the 1980 American shad Juvenile 108 Recruitment Survey. VIII. 109 Numbers of young-of-the-year Alosa aestivalis and Alosa pseudoharengus caught by haul seine per sampling period during the 1980 Juvenile Recruitment, Survey. ix Page Ix. Numbers of young-of-the-year Alosa aestivalis and 1-10 Alosa pseudoharengus caught by otter trawl per sampling period during the 1980 Juvenile Recruitment Survey. X. Numbers of young-of-the-year Alosa aestivalis and ill Alosa pseudoahrengus caught by haul seine per sampling station during the 1980 Juvenile Recruitment Survey. 4 Xi. Numbers of young-of-the-year Alosa aestivalis and 112 Alosa pseudoharengus caught by otter trawl per sampling station during the 1980 Juvenile Recruitment Survey. 114TRODUCTION Historically, the principal shad river in Maryland has been the Susquehanna (Mansueti and Kolb 1953). Prior to 1980, a commercial shad fishery had existed there for over 200 years. Similarly, a successful sport fishery had existed in this regio n since the early 1930's. Because of the sharp, continuous statewide decline in the numbers of adults harvested since the early 1970's the 1980 Maryland shad season was closed. The most precipituous decline occurred in the Susquehanna drainage: The 1971 reported commercial catch of American shad from the Susquehanna River and Flats combined was 184,221 pounds while the reported 1979 catch for this samearea was 14,319 pounds (Maryland Tidewater Administration MTA in-file data) Concerned by the seriousness of this situation, the tw@ Tidewater Administration of Maryland's Department of Natural Resources proposed a long term investigation of American shad in the upper Chesapeake Bay. The primary objective of this study is to assess the status of head-of-the-Bay shad stocks, specifically those utilizing the Susquehanna-River drainage. The information obtained will be used to formulate management policies to restore American shad to stable, harvestable levels. To meet the primary objective, five separate jobs were initiated: tagging and population estimate, population characterization, creel census, juvenile recruitment survey, literature review and survey. The five year project, initiated in February, 1980, is funded under The Federal Aid in Fish Restoration Act, PL 81-691, and the Power Plant Siting Program of the Maryland Department of Natural Resources. 2 JOB .1, TAGGING AND POPULATION ESTIMATION' INTRODUCTION IP A'lprerequisite to effectively manage an exploited fish stock is to determine how many individuals comprise the -population under investigation. .Since 1965, the state of Connecticut has been utilizing a mark-recapture program in estimating the numbers of American shad ascending the Connecticut River each spring co spawn (Crecco 1979). -lie data accumulated from this procedure has been one of the major factors in that state's efforts to effectively manage their shad stocks. Similar efforts on the Delaware River by New Jersey and Delaware state conservation personnel have also aided in effective management of.that river's American shad stocks (Lupine 1980). FeW population estimates for -k-nerican shad in Maryland waters have been made. Wall=g (1954) estimated the American shad population (in pounds) in Maryland waters from 1.944 to 1952 based on a single tagging experiment conducted in 1952 and the commercial catch records from 1944 to 1952. These estimates appear below: F YEAR COMIMERCIAL CATCH ESTIMATED POPULATION (lb.s.) (lbs.) 1944 661,005 2,412,427 1945 556,141 1,951,372- 1946 653,863 1,841,882 1947 768,830 1,800,539 1948 892,852 1,988,535 1949 949,690 2,168,242 1950 1,342,401 3,274,149 1951 1,486,616 3,046,344 1952 1,487,085 2,836,193 St. Pierre (1978) estimated the average annual population of American shad in the Susquehanna River and the extreme northern portion of Chesapeake Bay from 1890 to 1904 to be 1,790,000 fish. This computation was based on the average annual commercial harvest for this 15 year period plus the estimate that approximately 24% of the total population was harvested during this time. Because of the time lag between past and present population estimates of American shad and the inadequacies of pfevious efforts, a tagging exp eriment was undertaken to determine the numbers of American shad utilizing the Susquehanna River, Susquehanna Flats, and Northeast River to spawn. An extensive population evaluation would aid the Maryland Department of Natural Resources in its attempts to monitor the American shad in what was historically its most important spawning/nursery area, and in using the accrued data for future management decisions. METHODS AND MATERIALS Tagging of adult American shad was undertaken at various sites within the Susquehanna River, Susquehanna Flats, and Northeast River between April 22 and May 31, 1980 during the peak of the spawning run for this species (Figure I, p. 14). Fish were captured in commercially operated pound nets and anchor gill nets. Drift gill nets were also employed but wereunsuccessful in catching shad. Three pound net sites were located along the shore of the Northeast River at its juncture with the Susquehanna Flats. A fourth pound net site was located at the mouth of the Susquehanna River near Perryville. Drift gill nets were fished along the east shore of the Northeast River and in the Susquehanna River near Port Deposit and Havre-de-Grace. Gill net dimensions (both anchor and drift) were 1,000' x 6' and ranged from five to five and one half inch stretched mesh. All gill net sampling was done between 12:00 MI and 6:00,AM. Pound nets were sampled every day from 6:00 AM to 12:00 PM. All tagging was done with a Dennison Floy Tagging Gun, Model FD-67, using plastic anchor t@Lgs four inches in"length. 4 Fish were taken from the nets, measured for length, scale samples taken, sex determined, and tagged as expeditiously as conditions would allow. Under certain circumstances, to minimize stress, IP the fish were only tagged and immediately returned to the water. Data from dead shad found in the nets, including weights, was also collected. Tags were inserted into the dorsal musculature posterior to th e dorsal fin at an angle conducive to streamlining. Tag retention appeared to be satisfactory and did not seem to affect tag return data. A $5.00 reward was offered for each _J tag returne,@. RESULTS A total of 399 American shad were examined during the 40 days of sampling. Breakdown of collection by gear types is presented in Table 2, p. 12. Figure II, p.13 illustrates the time frame in which pound net and gill net captures were made. Of the 399 fish examined, 147 were t@igged successfully and release d from the four pound nets and two anchor gill nets. Stress among captured fish may have caused some post-release Ir mortality. Fish taken from the four pound nets were tagged and released with good success and did not seem to exhibit the degree of stress that was observed in fish captured by, tagged, and released from the anchor gill nets. Mortali ty for fish captured in the anchor gill nets appeared to be higher than those captured in the pound nets. Another problem encountered with the use of the anchor gill nets was that of immediate recapture of the newly marked. fish from the same net. Fish were initiallyreleased on the downstream side of the gill net but since this gear is fished under no flow river conditions there was no current to carry the tagged fish downstream away from the nets. The use of a holding tank to transfer the newly marked fish to deeper water away from the tagging area was moderately successful. Initially, population estimates were to be made using multivariate population models such as the Jolly-Seber stochastic and Bailey triple catch deterministic models (Ricker 1975). However, since there were only thirteen recaptures, these population models could not be utilized. An estimate for the adult spawning population of American shad in this area was attained, to an acceptable degree, by using Chapman's version of the standard Petersen estimate (Chapman 1951). Appropriate confidence limits were set by using tabulated limits for a Poisson dist--ibution as set forth by Ricker (1975). These computations are presentedin Table 3 while recapture data,is summarized below: Of the 13 recaptures- a) 10 were made by commercial fishermen 2 were made by sport anglers 1 was made by the Conowingo Dam Fish Lift b) 9 were originally tagged f rom pound nets 4 were originally tagged from anchor gill nets C) 5 fish were recaptured from the same location 5 fish were recaptured upstream from their tagging locations 3 fish were recaptured downstream from their tagging locations d) shortest recovery 1 day longest recovery 21 days average recovery 6.4 days Of the three shad recaptured downstream of their tagging location, two were recaptured one day after tagging by a commercial fisherman from Rock Hall, Maryland,approximately 30 nautical miles south of their tagging location. Leggett (1976) found that a majority of the American shad he tagged with ultrasonic tags (both internal and external) on the Connecticut River initially moved downriver as a possible 6 result of physiological shock and disorientation related to capture and tagging. The third downstream recovery was that of a spent individual tagged 19 days previously and recaptured at the most southerly pound net, possibly indicating it was IF returning to the ocean. Specific information concerning e ach of the 13 recaptures is presented in Table 1, p. 11. F DISCUSSION Several problems were encountered in both collectingand analyzing tho data needed to estimate the number of American shad U, in the head of Chesapeake Bay. 1. A lack of sufficient capture sites within the specific spawning U area combined with a lack of time synchrony between netting effort and adult fish spawning waves caused the number of fish captured to fall below what was originally anticipated. Anchor gill nets, which ultimately caught a majority of the fish, were not successfully used until the latter part of the run. F American shad are not as hardy as other fish and it was feared IP that those caught in the anchor gill nets would be unfit for tagging. Pound nets on the other hand, permit the continuous movement of captured American shad thus minimizing much of the IP stressing conditions imposed on gill net caught fish. As a result of trial and error, however, it was found that by fishing only one or two boxes of gill-net at a time, continuously checking the nets for fish, and using an aerated holding tank this gear would be used to collect shad for tagging. The majority of the shad lost in the anchor gill nets occurred before these techniques were employed and perfected, and most of the fish captured by this gear during the latter part of the run were.successfully tagged and returned to the water. Of the 31 fish lost in the pound nets, 19 were the result of the late arrival of the tagging team to the pound nets on April 22. Table 2 presents a comparison of gear types employed to catch American shad and their relative success. 7 2. As stated previously, the lack of sufficient numbers of recaptures eliminated the use of multivariate population models such as the Jolly-Seber which are specifically designed for use with open populations that are subject to immigration and emmigration. Ricker (1975) states that if the number of recaptures is small, say less than four for any of the several recapture periods Ue. one week) the population estimate is subject to bias. 3. A number of problems were associated with the use of a Petersen population estimate. Ricker (1975) notes six conditions thatshould be satisfied to obtain a valid Petersen estimate; a. the marked fish suffer the same natural mortality as the unmarked fish b. the marked and unmarked fish are equally vulnerable to fishing C. the marked fish do not lose their marks 0 d. the narked fish become randomly mixed with the unmarked fish e. all marks are recognized and reported on recovery f. there is only negligible recruitment to the catchable population during the time the recoveries are being made. Tagging equipment and procedures were quite similar to those employed on the Delaware (Lupine 1980) and on several rivers in South Carolina (Crochet et al. 1976). Data from these studies indicated little tag induced mortality and good tag retention. Because of the thinness of the spagetti tag used and its placement at a streamlined angle, tag-induced excess fishing mortality from these areas was found to be virtually non-existent. These same observations were also noted for-the 1980 Susquehanna tagging operation. It would be difficult to prove or disprove whether the tagged fish become randomly distributed with the untaggedindividuals but i.t seems reasonable to 8 assume that if the tagged fish were released in good physical r condition their ability to keep up with the untagged fish should not be impaired. No mention of this problem was made in other shad tagging studies (Crochet et al. 1976, IP Minta etal.1980, Lupine 1980). The offering bf a*$5.00 reward for each tag returned was thought to provide sufficient incentive for reporting the recapture of American shad during the present study. Violation of assumption f interjects a source of bias into the Pet(_rsen estimate. Since American shad enter their natal rivers in several spawning waves or pushes, they are not all available for possible capture, tagging and recapture at one time. The general trend on the Susquehanna River during previous years has been for the shad run to begin during the last two weeks of April and continue until the end of May, depending on water temperatures and river conditions. Figure IIindicates that during the course of the 1980 tagging experiment possibly three'different spawning pushes were noted. Ricker's assumption f may possibly be met if IP -one considers the fact that once the migrating American, shad reach the Susquehanna area they can go nowhere else r because of the presence of the Conowingo Dam. Since all of the fish that were observed and collected by the various gear types were fish homing to this area, one is dealing with only Susquehanna fish regardless of the time frame in which they were observed. This problem of timing with respect to the various spawning pushes does not seem to deter the use of the Petersen statistic in estimating populations of American shad in other east coast rivers (Lupine 1980, Crec'co 1979). Ricker (1975) states that the violation of assumption f will produce a population estimate that is too high assuming that the other five assumptions are satisfied. It seems tj . thon, that tisinq the modified Petersen formula probable 9 overestimated the 1980 spawning population of American shad in the Susquehanna drainage. Since the estimated population was only 2,675 spawning adults, the overestimated figure further emphasizes the severely depleted shad stocks utilizing the upper Chesapeake Bay. 4. Another source of bias associated with a Petersen estimate is the low number of recaptures. Bailey (1951) states that a large scale recapture effort may be necessary to make a reliable population estimate. Ricker (1975) noted that lower numbers of recaptures cause the Petersen estimate to become biased and, therefore, less reliable, although some confidence is gained through the use of a Poisson distribution as was done for the Susquehanna data (Table 3, p. 13). The sources of recaptures during the 1980 study were to have been the local sport and commercial fisheries. However, the progresive, drastic decline in the spawning stocks of American shad necessitated a statewide closure of Maryland waters for the 1980 season. Because of this closure, the incidental sport and commercial fishing effort for American shad produced a limited number of returns, with the bulk coming from commercial watermen specifically hired by the Department of Natural Resources to capture fish for tagging. Admittedly, this made for a somewhat limited population estimate, but in analyzing the current situation the Department considered the protection of the remaining brood stocks to be of greater importance than extreme precision of,estimates. Although overall stock size is greatly reduced, sufficient numbers of American shad.may be present in this area to allow for a more reliable population estimate, provided the number of recaptures increases. This will be attempted in 1981 through greater utilization of local commercial watermen in an effort to improve sampling techniques and timing. It is hoped that these changes will increase data reliability and allow the use of more sophisticated statistical techniques to provide more accurate information. 10 S UMMA RY 1. Of the 399 American shad collected at the Head-of-the-Bay, 147 were tagged and released. Thirteen of these were recaptured. 2. A population estimate of 2,675- American shad was made utilizing the Petersen formula. 3. Stress and mortality problems associated with the use of anchor gill nets to capture shad for tagging were encountered. After corrective measures were implemented, these problems were reduced, allowing for the successful tagging of gill net caught shad. 4. Increased tagging and re capture' efficiency may permit the use of more accurate population models in estimating future Susquehanna shad populations. TABLE Capture-recapture dates, locations and gear types for thirteen recaptures of tagged American shad during 1980. Date Date Tagging Gear Recapture Gear Tagged Recaptured Location Type Location Type 4-22-80 5-7-80 NE River PN Perryville GN d 4-25-80 4-30-80 NE River NE River PN 4-29-80 4-30-.80 NE River PN Rock Hall GN 4-29-80 4-30-80 NE River PN Rock Hall GN 5-7-80 5-13-80 Susq. River GN Susq. River GN 5-12-80 5-13-80 Susq. Flats PN Susq. River GN 5-8-80 5-13-80 Susq. River GN Susq. River GN 6d 5-12-80 5-14-80 Susq. River GN Susq. River GN 5-12-80 5-14-80 Susq. River GN Susq. River GN 5-6-80 5-11-80 Susq. Flats PN Con. Te. HL I;J 5-10-80 5-23-80 Susq. Flats PN Con. Te. FL 4-23-80 5-14-80 NE River PN Con. Te. HL 5-12-80 5-31-80 Susq. Flats PN NE River PN Gear Type Abbreviations GN = gill net PN = pound net HL = hook & line FL = fish lift IX Location Abbreviations Con. = Conowingo Dam NE = Northeast River Con. Te. = tailrace 12 TABLE 2. Comparison of total catch, number tagged, number lost, and % net mortality by location and gear type for American shad captured in the Susquehanna River, Susquehanna Flats, and Northeas t River during 1980. Total No. No. % Net Location Catch Tagged Lost Mortality A. Pound'Aets TP 50 29 21 8 7 cc 1 1 cc 11 17 16 1 Pp 45 37 8 Sub Totals 120 89 31 26 B. Anchor Gill NE R. 0 0 0 Nets Sus. R. 144 65 79 Sub Totals 144 -6-5 7 -9 55 C. Conowingo Fish Lift Dam 135 0 ? D . Drift Gill NE R. 0 0 0 Nets Sus. R. 0 0 0 E. Grand Totals 399 154* 110 42** tagged used in Petersen estimate = 147: 7 fish were recaptured in anchor gill nets immediately after tagging, died, and were not included in number tagged but as.I.ost in population estimate. figure based on pound net and anchor gill net totals only @0 13 TABLE 3. Population estimate of adult American shad utilizing the Susquehanna River, Susquehanna Flats, and Northeast River for,1980. FROM CHAPMAN (1951): N = (M + 1) (C + 1) where: N = population estimate C = number of fish R + 1 examined for-marks R = number of fish recaptured M = number of fish marked For the 1980 Survey C = 252 R = 13 M = 147 Therefore - N (147 + 1) (252 + 1) 13 + 1 148 x 253- 14 37,444 14 2,675 IN FROM RICKER (1975): Calculation of sampling error using recapture numbers in conjunction with a Poisson distribution approximation and acceptable confidence limits. Using Chapman (1951) N* (M + 1) (C + 1) where: R tabular value Rt + 1 (from Ricker p343) Upper N1 (147-+ 1) (2 5Z + 1) = 4,740 @ 95% confidence 6.9 + 1 limits Lower N* (147 + 1) (252 + 1) = 1,607 @ 95% confidence limits 22.3 + I iou Punod 9W TTT5 1Oq3Uv TTT-5 -4-;T-TP -0861- bUTjnp Pp1qf5,. UUDTX;Durv qTnpp 5uT5Bt,4 UT 2MIS fi UOTIVOOT PUP TT4n s' 1 4 PM ;,w c 9 9 14 1 ww%m 11,112, 1w, c . , ;6. t a a r (5 C, C. 311A" FIGURE II. Numbers of American shad caught for tagging by all gear types and by date from the Susquehanna River, Susquehanna Flats, and Northeast River during 1980. 50 40 E-1 @D 4 30 20 10 0 22 1 -15 31 <-APRIL MAY DATE CAUGHT 16 JOB 11, POPULATION CHARACTERIZATION INTRODUCTION Effective management policies can only be implemented when an extensive data base exists from which to draw information. Such a data base exists in Connecticut where the population characteristics of American shad have been monitored for many years (Fredin 1954, Judy 1961, Jones et al. 1976, Leggett 1976, Crecco 1979, Minta et a?. 1980). In this system such parameters as growth and survival rates, total, fishing and natural mortality rates, and annual fishing rates have been determined from length and weight frequencies, sex and age composition, adult spawning history, and commercial and sport fishing data since 1966 (Crecco 1979). Other estim ates made for Connecticut River shad include recruitment, escapement, and return per spawner based on adult age structure. The accumulated data are then utilized for determining different yields associated with changes in fishing effort for the exploited shad fishery. A stable shad population has been the result of this research and subsequent management which allows sufficient escapement while permitting a viable economic harvest. Most of the literature concerning Maryland American shad stocks discusses historical overviews of the commercial fishery, catch records, and catch-per-unit-effort (CPUE) estimates of those landings (Mansueti and Kolb 1953, Walburg 1955, Mansueti 1958, Walburg and Nichols 1967, Forester and Reagan 1977, St. Pierre 1978). Very little is known about the fluctuations in American shad stocks for the Susquehanna River other than these historical reviews. There has been no long term monitoring program of the U. population characteristics of Susquehanna River American shad. La Pointe (1958) presented sex ratios, age class, spawning history and length data for Susquehanna shad. RMC (1979) summarized In, sex and age composition data for shad collected at the Conowingo Dam fishli-ft and from sport anglers between 17 1972 and 1979. In that eight year period, however, only 451 fish were examined, and in one year, as few as six fish were collected (Table 4, p. 24). . In 1979, a pilot study of Susquehanna River American shad stocks was made. The study, designed to gather information concerning population characteristics of upper-Bay shad, was expanded in 1980 to measure length and weight frequency distributions, sex and age composition, and adult spawning history data for five years. This will allow estimation of the parameers needed for effective management of Maryland shad stocks. For example, since the gear used by upper Chesapeake Bay shad fishermen is highly size selective, accumulation of length-weight data would allow the Department of Natural Resources to better protect a safe number of virgin spawners who make up the majority of the adult population and older, more fecund repeat spawning individuals through limitations in net mesh sizes. METHODS American shad were collected at various locations in the Susquehanna system as described in JOB I. A sample of approximately 12 or more scales was taken midway between the dorsal fin and the midline on the left side of each fish and placed in a scale 60 envelope. The date and location of capture, net type, fork length (mm), sex, and weight (grams) were recorded on each envelope. Weight measurements were taken from dead fish only. On occasions when it appeared that a fish was stressed due to 4W handling or confinement in the sampling gear, scale samples were not taken so as to minimize handling and possible mortality@, since the fish were being tagged for use in a population estimate. Scale samples were prepared for age and spawning history determinations by selecting 4 to 6 non-regenerated scales from each envelope and cleaning each one thoroughly with soap and 18 water. Clean scales were impressed on 25 mm. by 76 mm. acetate jr slides with a roller press. The slides were then placed in a microprojector and read at 2.5X magnification. Two biologists read each scale for age and spawning marks according to the techniques developed by Cating (1953). If the two readers were in disagreement, the slide was set aside to be re-read later. If agreement could not be reached after reading the slide a second time, that-sample was discarded. Age was determined by the number of true annuli present plus the outer edge of the scale (Cating 1953). Spawning history wac indicated by the presence or absence of a spawning mark near the scale periphery. F RESULTS To reduce stress-induced mortality of captured American shad, not all physical measurements were taken for each fish collected. Consequently, sampling sizes for such measured parameters as length, weight, age and spawning marks are not equal. The sample sizes for sex, length, weight, and age of male, female, and spent shad are presented below: SAMPLE SIZE Variable Female Male Spent Sex 160 97 Length 124 69 5 Weight 57 16 Age 117 67 4 The sex ratio of 257 shad examined was 1.6:1, female to male (Table 6, p.28). The mean fork length for females was 461 mm, while that for males was 428 mm (Table 5., p.26). The mean weights for female and male shad werel,580 grams and 1,240 grams, respectively (Table 5 , p. 26) Figures IdIand IV present the length frequency distributions by sex for adult shad. 19 There,were196 scale samples collected for age structure data and spawning history. Because some scale samples were discarded as unusable, there were 188 slides from which age and spawning history could be determined. Table 6, p. 28, presents scale analysis data. The dominant age class, age IV, comprised 57.4% of the shad examined, while age V individuals made up 33% of all shad collected. Only 11.7% were determined to be repeat spawners (Table 6). The percentage of male shad which were virgin fish was 83.6%, while the female population consisted of 90.6% vi-:gin recruits. DISCUSSION Tables 6, 7, and 8 (p. 28, 30, and 34) present character- ization data collected from Susquehanna American shad captured in 1979 and 1980, and for othereast coast shad rivers. Of note arethe following: 1. Little age structure change was noted for upper Chesapeake Bay shad captured in 1979 and 1980; the dominant age class for both years was IV. The incidence of repeat spawners increased ,Mi slightly in 1980, although this level was far below the 37% reported by LaPointe (1958) for Susquehanna River American shad. Slight increases were noted in mean length for both males and females in 1980 while length at age ranges were similar for both years. The most noticeable change between the two year's catch was in the sex ratio 4M which changed from.strongly female in 1979 to slightly female in 1980. During 1979, approximately 90% of the American shad examined from the Susquehanna River and Flats were collected by gill nets. In 1980, nearly 50% of the fish sampled were taken from commercial pound nets, a less selective gear. This change in sex ratios appears to be an artifact of the various sampling gears employed for the two years. 2. 1978 sex ratios for Chesapeake Bay shad stocks from the York, James, Rappahannock, and Pamunkey Rivers, Virginia were similar to 1979 Susquehanna sex ratios. This similarity may, again, be due to the fact that fish collected 20 in all the Virginia rivers in 1978 and from the Susquehanna r in 1979 were taken with size selective gill nets. Age structure, however, appears to be different between the two with age class VI individuals dominating the Virginia runs as opposed to age IV for the upper Chesapeake Bay population. Few age III and IV individuals were collected from these Virginia rivers in 1978. No data on repeat spawning was available from these Virginia caught fish. 3. Age striicture of 1978 caught shad from Albemarle s.-Sound North Carolina was similar to age structure of Virginia shad. However, certain differences between the two.were noted: a) the dominant age class for the North Carolina fish was V instead of VI, b) the numbers of younger age classes (III and IV) was much greater for North Carolina shad. Sex ratios of Albemarle Sound fish were quite different from Maryland and Virginia Chesapeake Bay stocks and more closely represented the.l:l ratio reported by Leggett (1976). The percentage of repeat spawners for 1978 Albemarle Sound fish 1PO was lower than for Susquehanna shad. This agrees with the findings of Leggett and Carscadden (1978) who concluded that the incidence of repeat spawners decreased with decreasing latitudes and was virtually non-existent in South Carolina, Georgia, and Florida. 4. Delaware River American shad captured in 1978 and 1979 exhibited a similar age structure to upper Chesapeake Bay fish with age IV individuals dominating. Beginning in 1978, however, an influx of three year old males occurred on the Delaware which increased greatly in 1979. Both mean length and length ranges at age were usually greater for 1979 Delaware shad as opposed to their 1979 and 1980 Susquehanna counterparts (Table 6, P. 28). Numbers of repeat spawners were significantly less for Delaware River shad due primarily to adult mortality during seaward migration (Sykes and Lehman 1957, Chittenden 1969). 21 5. Mean length and length ranges by age for both male and female Connecticut River American shad collected in 1979 were greater than 1979 and 1980 Susquehanna fish. However, the differences between 1979 Connecticut and 1979 Susquehanna shad were very slight for all age groups. The 1979 Connecticut River sex ratio was also quite similar to that found for 1980 Susquehanna fish. The greatest difference between the two stocks appears to be in the spawning history. The percentage of repeat spawners utilizing the Connecticut River in 1979 lid was 20%, with a 15 year average (1965-1979) of 36% (minta et aL1980). Susquehanna River American shad exhibited only a 10.4% and 11.7% incidence of repeat spawning during 1979 and 1980,respectively. The data presented in Tables 6, 7, and 8 and summarized above were from American shad collected with various commercial gear types; therefore, some degree of sampling bias has been introduced. Measured parameters reflect characteristics of the commercially harvested sample and not the entire spawning population. The mesh size of commercial gill nets fished in the non-Maryland areas is unknown. However, it seems reasonable to assume that the mesh size employed by each system's commercial fishermen does not drastically change within that system. This is because a river's watermen are all fishing on the same stocks. Upper Chesapeake Bay gill net fishermen select large net sizes (54 to 5 3/4 inch stretch mesh) designed to capture the larger, more robust shad. Males, which are normally smaller than females at any given age are less likely to be captured by these larger mesh nets. An extra economic incentive also exists for taking females because of their roe. Preliminary pound net samples from the Connecticut River (minta et al. 1980) indicated that there we re major differences in the sex ratios of pound net vs gill net captured American shad in 1980. Connecticut DEP personnel theorize that the probability of tagging and recapturing small adult shad was reduced by gill net fishing L that is highly size selective. Adult collections of American shad from the Delaware River are made with less size selective haul seines (Friedersdorff and Baren 1978, Lofton 1979, Lupine 22 1980). The 1979 Delaware sex ratio, 53% males and 47% females is very similar to the 1:1 proportion as reported by Legg ett (1976). It would appear from analysis and comparison of the 1979 and 1980 Susquehanna shad data that this stock can be characterized as a run primarily supported by two very small, virgin age classes with relatively few repeat spawners. These conditions provide little buffering against man-induced and natural environment:-,l problems. The situation on the Connecticut River is such that each year's run is supported by more than one large year class and a large number of more fecund repeat spawners. Consequently, this is the most stable shad fishery of all major east coast rivers. With few repeat spawners present, the recent increases in Delaware River shad runs are due primarily to the presence of several strong year classes that have successfully passed through the Philadelphia pollution zone. Chittenden (1975) found that large increases in the 1962 and 1963 Delaware shad runs were the result of extremely large year classes produced in 1958 and 1959. Chittenden noted'a shift in the sex ratios from strongly female in 1960 to strongly male in 1961 and 1962. He concluded that since males tend to enter the fishery one year before females, a sudden large increase in the proportion of male fish appears to be a strong indicator of year class strength and hence run size for the following year(s) as the females return to spawn. The 1963 Delaware shad run was one of the largest in the previous 45 years. Similar increases in the proportion of males in 1978 and 1979 indicated strong year class production in 1974 and 1975. Subsequent Delaware River sport and commercial catches of American shad for the past four years have also increased dramatically. As previously stated, the shift in the sex ratio of Susquehanna shad (Table 6) from 1979 to 1980 was probably due to changes in the gear types employed to capture adults. If an actual increase in male fish did take place a significant increase in 1980 23 Susquehanna age III male fish should have occurred as it did on the Delaware in 1978 and 1979. However, this did not happen on the Susquehanna and it appears that two very reduced, virgin age classes, with little help from stronger year classes and more fecund repeat spawners will continue to support the already limited upper Chesapeake Bay American shad runs. SUMMARY 1. General similarity was noted between 1979 and 1980 upper Chesapeake Bay American shad runs. 2. Although similarities existed for some characteristics, Susquehanna stocks exhibited definite differences with other east coast American shad populations. 3. The 1979-1980 upper Chesapeake Bay runs may be characterized as being supported by two remnant virgin age classes with a small percentage of repeat spawners. 4. Comparison with both Connecticut and Delaware River American shad runs indicates that with no significant increase in the numbers of virgin males, an indicator of increased year class strengths, and in the numbers of more fertile repeat spawn ers, the present reduced levels of American shad utilizing the head-of-Chesapeake Bay will continue for the forseeable future. 24 TABLE 4,-. Age composition of Susquehanna River American shad collected by the Conowingo Dam Fish Lift and by sport anglers from 1972 through 1979. YEAR AGE CLASS FISH LIFT SPORT ANGLERS TOTALS M f M f 1972 111 8 0 - 8 IV 37 15 - 52 V 10 19 - 29 VI 0 9 - 9 Total 55 43 98 1973 IV 1 0 1 V 1 2 3 VI 0 1 1 VII 0 1 1 Total 2 4 6 1974 111 1 0 4 0 5 IV 2 1 7 14 24 V 2 3 2 8 15 VI 0 0 0 1 1 Total 5 4 13 23 45 1975 IV 4 7 15 9 35 V 0 2 4 8 14 Vi 0 0 1 1 -2 Total 4 9 20 18 51 1976 111 0 0 1 0 1 IV 4 .3 7 8 22 V 2 8 .2 8 20 VI 2 1 1 0 4 VII 0 1 0 0 1 Total 8 13 11 16 48 25 TABLE 4 - continued. YEAR AGE CLASS FISH LIFT SPORT ANGLERS TOTALS m f m f 1977 111 0 0 2 0 2 IV 2 6 18 5 31 V 2 8 13 33 56 VI 0 0 0 7 7 Total 4 14 33 45 96 1978 V 2 1 8 6 17 vi 0 2 4 12 18 VII 0 2 1 1 4 Total 2 5 13 19 39 1979 111 1 0 0 0 1 IV 4 3 2 1 10 V 7 17 3 7 34 VI 6 8 1 4 19 VII 2 1 0 1 4 Total 20 29 13 68 TOTALS 1972 1979 100 121 96 134 451 TABLE 5 Mean fork length (mm), mean weight (kg), and length and weight ranges by sex and age class for American shad collected from the Susquehanna drainage during 1979 and 1980 by various gear types. GILL.NET 1,rUND NET RANGE RANGE AGE SEX VARIABLE NO. MEAN MIN. MAX. AGE SEX VARIABLE NO. MEAN MIN. MAX. A. 1979 III m length 3 375 361 385 weight 3 0.72 0.68 0.74 IV M length 29 420 375 457 weight 27 0.98 0.45 1.39 f length 152 447 365 487 weight 152 1.47 0.74 2.16 V m length 11 455 408 504 weight 9 1.27 0.91 1.59 f length 126 461 420 522 weight 125 1.66 0.91 2.07 VI M length 2 508 498 519 weight 2 1.76 1.71 1.81 f length 3 495 470 520 weight 3 1.85 1.64 2.04 TABLE 5 - c.-)ntinued. GILL NET POUND NET RANGE RANGE AGE SEX VARIABLE NO. MEAN MIN. MAX. AGE SEX VARIABLE NO. MEAN MIN. MAX. B. 1980 III m length 2 38-11 373 402 111 m length 10 379 350 412 weight 1 0.70 - - weight 1 1.80 - - IV m length 12 417 387 436 IV m length 23 429 408 459 weight 4 0.97 0.80 1.10 weight 3 1.16 1.00 1.40 f length 32 445 398 "475 f length 37 446 415 483 weight 21 1.39 -0.90 2.30 weight 11 1.55 1.00 2.40 V m length 6 456 441 482 V m length 12 461 440 483 weight 3 1.26 1.20 1.30 weight 1 1.50 - - f length 23 476 444 499 f length 20 481 440 530 weight 18 1.67 1.20 2.30 weight 3 2.03 1.80 2.40 VI m length 0 - - VI m length 2 495 487 503 weight 0 - - - weight 2 1.85 1.70 2.00 f length 1 537 - - f length 2 527 527 528 weight 1 2.00 - - weight 1 2.00 - VII f length 1 524 - - VII f length 0 - weight 0 - - weight 0 a"-,, O@M_ elm i., I% "M. 19- @J' -,OR, or, - "R or-, EF-1. me - EF-i on: MIR or M TABLE 6 Age frequency, number, and percent repeat spawners by sex for American shad collected from the Susquehanna drainage during 1979 and 1980 by various gear types. GEAR SEX AGE CLASS % REPEAT YEAR TYPE SEX RATIO NO. III IV V VI VII SPAWNERS 1979 gill m 14% total= 45 3 29 11 2 net repts= 15 0 7 6 2 33.0 f 86% total=281 152 126 3 repts= 19 2 14 3 6.8 TOTALS total=326 3 181 137 5 repts= 34 0 9 20 5 10.4 1980 gill m 26% total= 20 2 12 6 net repts= 2 0 0 2 10.0 f 74% total= 57 32 23 1 1 repts= 7 1 5 0 1 12.3 TOTALS total= 64 2 44 29 1 1 repts= 9 0 1 7 0 0 11.7 pound m 44% total= 47 10 23 12 2 net repts= 9 0 8 1 0 19.1 f 56% total= 60 38 20 2 co repts= 4 0 3 1 6.7 TABLE 6 continued. GEAR SEX AGE CLASS % REPEAT YEAR TYPE SEX RATIO NO. III IV V VI vii SPAWNERS 1980 pound sp total= 4 3 1 net repts= 0 0 0- 0.0 TOTALS total=lll 10 61 32 4 repts= 13 0 8 4 1 12.1 NJ RM". @M__ MMI R-M I" - ULM qp: " "M-1- Me- TABLE 7. Age frequency, number, and percent repeat spawners by sex for American shad collected from selected east coast rivers during 1978 and 1979 by various gear types. GEAR SEX AGE CLASS % REPEAT YEAR TYPE SEX RATIO NO. III IV V VI VII VIII SPAWNERS 1 A. Connecticut River 1979 gill m 32% total=174 9 92 67 6 net repts= 40 no individual data 23.0 f 68% total=374 147 205 19 2 1* repts= 70 no individual data 10.0 TOTALS total=548 9 239 272 25 2 1 repts=180 no individual data 20.1 B. Delaware River 1978 2 haul m 69% total=4 07 48 245 112 2 seine repts= ? no data available NA 31% total=188 1 39 118 25 5 repts= ? no data available NA TOTALS total=595 49 284 230 27 5 repts= ? no data available NA 00 TABLE' 7 continued. GEAR SEX AGE CLASS % REPEAT YEAR TYPE SEX RATIO NO. III IV V VI VII VIII SPAWNERS 19793 haul m 53% total=429 115 260 51 3 seine repts= 10 no individual data 2.3 f 47% total=387 5 183 160 39 repts= 6 no individual data 1.5 TOTALS total=836 120 443 211 42 repts= 16 no individual data 1.9 C. Rappahannock River 4 1978 gill 22% total= 43 1 11 24 6 1 net repts= ? no data available NA f 78% total=149 1 34 102 12 repts= ? no data available NA D. York River4 1978 gill m 30% total= 74 35 34 5 net repts= ? no data-available NA f 70% total=172 1 39- 123 9 repts= ? no data available NA IL GEAR SEX AGE CLASS % REPEAT YEAR TYPE SEX RATIO NO. IV V VI VII VIII SPAWNERS Pamunkey River4 1978 gill m 17% total= 30 1 1 9 17 2 net repts= ? no data Available NA f 83% total=149 36 101 12 repts= ? no data available NA F. James River4 1978 gill m 28% total= 39 1 12 26 net. repts= ? no data available NA f 72% total= 99 2 29 60 8 repts= ? no data available NA .G. Albemarle Sound4 1978 unkwn. m 58 total=285 3 54 188 39 1 repts= 19 no individual data 6.7 42 total=205 9 110 78 8 repts= 11 no individual data 5.4 TOTALS - - - - - tatal=490 3 63 298 117 9 repts= 30 no individual data 6.1 TABLE 7 continijed. fish was recorded as VII+ in original. text (Minta. et a.1.1980)_ I from Minta, et al.1980 2 from Lofton 1979 3 from Lupine 1980 4 from Johnson, et al.1978 "T 34 TABLE mean fork length (cm) and length ranges by sex and age classes for American shad collected from the Connecticut and Delaware Rivers during 1979. RIVER GEAR SYSTEM, YEAR TYPE SEX VARIABLE III IV V 'V1 VII Conn.1 1979 gill m number 30 180 100 10 net R len5th 39 43 46 48 range 33-42 39-46 44-48 45-51 f number 0 189 268 24 2 -A length 47 49 53 57 range 40-50 45-52 50-55 55+ Del.3 1979 haul m number 115 260 51 3 seine R length 43 45 46 45 range 32-47 39-51 42-49 45-46 f number 5 185, 160 39 R length 45 49 50 51 range 43-48 43-54 43-55 47-58 1 from Minta, et al.1980 2 from Minta, personal communication 3 from Lupine 1980 FIGURE II. Length frequency distribution for male American shad collected in the Susquehanna System in 1980. N 69 X LENGTH 428mm 8- F R. E Q 6- U E N C 4 Y 2 3 3 3 3 3 3 3 3 3 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 6 6 7 7 8 8 9 9 0 0 1 1 2 .23 3 4 4 5 5 6 6 7 7 8 8 9 9 0 0 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 0 5 LE14GTII (rm) Ln ow MR.:. 1"k, W-a W, FIGURE III-Length frequency distribution for female American shad collected in* Susquehanna System in 1980. 12- N 124 LENGTH 461mm F 10- R E Q .U 8- E N C 6- Y 4- 2- 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 5 5 5 5 5. 5 5 5 9 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 0 0 1 1 2 2 3 3 4 5 0 5 0 5 01 5 0 5 0.,5 0 5 0 5 0 5 0 5 0 .5 0 5 0 5 0 5 0 5 0 LENGTH (mm) 37 JOB 111. SPORTFISHING SURVEY INTRODUCTION A non-uni form probability creel census (Pfeiffer 1966) was conducted from 3 May through 30 June 1980 in the area of the Susquehanna River from Conowingo Dam south to the river's mouth at Hav re de Grace. The non-uniform probability sport angli'ng survey makes use of prior fishing knowledge on a particular body of water, in this case the Susquehanna River (Whitney 1961, Carter 1973, RMC 1979). Selection of sampling probabilities, locations, and interview days and times is proportional to expected intensity as determined from these previous surveys. The non-uniform probability census also provides more reliable information with less expendit ure of effort and money (Pfeiffer 1966). The purpose of this survey was to determine fishing pressure, catch per unit of effort, harvest, and catch composition. Data from vow this survey is compared with previous surveys (Carter, 1973; RMC, 1979) to assess trends that have taken place in the sport fishery of the lower Susquehanna River. METHODS AND MATERIALS Thirteen access points were utilized in the 1970 survey but the present survey dropped the Riverside site because of low fishermen usage (fig. V). Probabilities for the twelve access points, time blocks, time units and associated sampling probabilities utilized in the 1980 survey are presented in Tables 9 and 10. The probabilities were the same as those used by RMC in 1979. The day and time probabilities were changed slightly to reflect the differences in fishing pressure during weekday holidays. Interviews were conducted with fishermen who had comple ted their fishing trips during the assigned time interval at a' 38 given access point. Anglers were canvassed concerning their mode of fishing, number in their party, state of residence, hours spent fishing, species catch composition and catch disposition. The survey questionnaire is presented as FigureVI. observed angler catch was expanded using the assigned probabilities for day, time and location. The expanded values estimated number of anglers, angler hours, harvest (fish kept), and total catch for the Susquehanna Rive r during the survey period. Anglers were also asked their opinion of the possible construction of a fishway at the Conowingo Dam and of the 1980 American shad fishing closure. RESULTS A total of 314 party interviews, comprising 74 9 individual anglers,' were conducted on 27 census days between 3 May through 30 June,1980. Of these, 565 (75%) were Maryland residents and 184 (25%) nonresidents. The average party trip length was 5.0 hr with 2.5 anglers per party. Interviewed shore and boat anglers spent 3,668 hours fishing and caught 4,741 fish of 19 different species. Catch, harvest, and success rate data are presented in Table 11. Anglers kept approximately 40% of their total catch. The dominant species caught was white perch (Morone americana). Channel catfish (Ictalurus punctatus), stripedbass (Morone saxatilis), and carp (Sj@in@us carpio) were also commonly taken. Sixty-one percent of the carp caught were retained, and anglers kept twice as many striped bass as they released. However, twice as many white perch and channel catfish were released as were kept. American shad were released because of the closure of the commercial and sport shad fisheries by the Maryland Department of Natural Resources. Catch per angler hour (CPUE) for selected species caught during this creel survey are found in Table 12. The CPUE for 39 white perch was 0.7375, while the CPUE for channel catfish and striped bass were 0.1892 and 0.1270, respectively. American shad CPUE was 0.0003. Estimated harvest of fish kept for the survey period was 50,432 with nearly half consisting of white perch (Table 13). Striped bass comprised 18% of the estimated harvest while channel catfish and brown bullheads comprised 16.2% and 7.4%, respectively. The CPUE for boat fishermen was greater (1.38 fish caught-per angler hour) than that experienced by shore angler's (1.21 fish caught per hour) . Of the 547 anglers responding to the opinion question, 68% favored construction of a fish ladder at Conowingo Dam while 30% had no opinion. Fifty-six percent of the anglers agreed with the imposed ban on commercial and sport fishing for American shad, while 38% offered no opinion. DISCUSSION Estimated sport fishing pressure in 1980 was similar to that observed in 1979 (RMC, 1979). There were 26,291 anglers in 1979 that fished 107,503 hours (Table 11). In 1980, the number of anglers (21,063) was 20% fewer than the previous year while the number of hours fished (109,764) increased by 21%. Susquehanna anglers caught 1.12 and 1.29 fish per hour during 1979 and 1980, respectively. Estimated sport fishing pressure in 1970 was greater than in 1980 (Tablell). There were fewer estimated anglers and less estimated fishing time expended in the present survey, but, the success rate, a possible measure of angler satisfaction, was greater than that observed a decade earlier. There was a 62% decrease in hours fished between 1970 and 1980, and a 63% decrease in the number of anglers. However, the success rate for 1980 was 1.29, 38% greater than the 1970 survey,success rate of 0.93. 40 Because sport anglers were required in 1980 to release all American shad caught, there was little data concerning sport angling for this species during the present survey. Only one shad was reported caught and subsequently released. It was rumored among anglers that more shad were taken from the Susquehanna River than were reported. However, there was no evidence to substantiate or refute this rumor. In 1970, the actual reported catch of American shad by sport anglers was 694. This comprised approximately 9% of the total sampled catch. In 1980, only one American shad was reported taken by hook and line which made up less than 1% of the entire sampled catch for this year. Observed catch per angler hour (CPUE), and species composition, both observed and expanded, for white perch, striped bass, and channel catfish can be found in Tables 12and 13. Approximately half of all white perch landed by anglers were recorded from the Lapidum access point; 45% by boat anglers and 5% by bank fishermen. An additional 25% of the white perch landed were caught by shore anglers in Shures Landing. These percentages are not simply an artifact of sampling intensity or sampling probability. The boat angler CPUE was 1.46 white perch caught per hour at the Lapidum site, twice the total calculated CPUE for this species in the 1970 survey (Table 1@. CPUE's for shore anglers at Lapidum and Shures Landing were 0.32 and 0.52 fish caught per hour, respectively. White perch CPUE for all sites experienced a 93% increase between F-4 1970 and 1980, although there was a 15% decline in actual numbers of fish caught. Forty-two.percent of the striped bass were landed by bank fishermen utilizing Shures Landing. CPUE for striped bass at this site was 0.15 per hour. An additional 32% were caught by boat anglers (CPUE 0.17) who had launched from Lapidum. Catch per angler hour of striped bass in 1980 was approximately 214% and 147% greater than in 1970 and 1979, respectively. There were 3.1 striped bass caught per trip with 1.8-stripers 41 kept per angler per trip in the present survey. In 1979, only 0.3 striped bass were kept per angler per trip. For shore and boat anglers, respectively, striped bass success rates were 450% and 27% better than in 1979. Seventy-six percent of the channel catfish caught during the pres ent survey were caught by shore anglers at Shures Landing. The CPUE for channel catfish at this site was 0.40 fish caught per hour which was twice the CPUE calculated for this species for the present 3urvey over all access points. The 1980 CPUE-for channel catfish increased 219% over 1970 but decreased 27% since 1979. The boat angler success rate for channel catfish in 1980 was 0.06, a 65% decline from 1979, while the shore angler success rate for this species increased by 43% from 1979 to 1980. SUMMARY 1. Seven hundred for ty-nine individual anglers were interviewed on 27 census days between 3 May and 30 June. 2. Sampled anglers spent 3,668 hours fishing and caught 4,741 fish of 19 species. 3. The four most frequently caught species were white perch, channel catfish, striped bass, and carp. 4. An estimated 26,291 anglers fished 109,764 hours and harvested 50,432 fish from the Susquehanna River. 5. Only one American shad was reported caught during the 1980 creel survey. woo 42 Table 9. Access points and comparison of associated sampling probabilities for the lower Susquehanna River Creel survevs,1970, 1979, and 1980. 1970 May-June 1979 1980 Access Point Probability Probability Probability 1. Shures Landing 0.16 0.17 0.17 2. Mouth of Deer Creek 0.03 0.03 0.03 3. Susquehanna State Park 0.05 0.03 0.03 4. Lapidum ' 0.30 .0.32 0.32 5. Baldwins Dock 0.05 0.03 0.03 6. Tidewater Marina 0 .03 0.02 0.05 7, Penn's Beach Marina 0.05 0.05 0.05 8. Tydings Park'Marina 0.05 0.05 0.05 9. Riverside* 0.01 0.01 0.01 10. Spanglers Rock Run Marina 0.05 0.09 0.09 11. Port Deposit Marina 0.05 0.04 0.04 12. Logan's Wharf 0.11 0.11 0.11 13. Owens.Fish House 0.06 0.05 0.05 *site dropped because of low fishermen usage. 43 Table 10. Time blocks, time units and associated sampling probabilities for creel census of lower Susquehanna River, May-June, 1930 Sampling Day Time Block Time Unit Probability Sunday A 0800-1200 0.10 1200-1600 0.50 1600-2000 0.40 1.00 Monday B 0800-1200 0.02 1200-1600 0.04 Tuesday 1600-2000 0.07 .0800-1200 0.02 1200-1600 0.05 1600-2000 0.12 Wednesday 0800-1200 0.02 1200-1600 0.09 1600-2000 0.11 Thursday 0800-1200 0.03 1200-1600 0.05 1600-2000 0.16 Friday @0800-120.0 0.02 1200-1600 0.04 1600-2000 0.16 1.00 Saturday C 0800-1200 0.10 1200-1600 0.50 1600-2000 0.40 1.00 44 Tablell. Comparison and characterization of data collected from the 1970, 1979, and 1980 Susquehanna River Sport Fishing surveys. A, NON-EXPANDEO TOTALS 1970 1979 1980 Survey Dates 3/28-6/21 4/28-6/30 5/3-6/29 No. of Interview Days 34 .29 27 No. of Anglers Interviewed 1,607 937 749 No.of Hours Fished 8,314 3,462 3,668 Mean Trip Length 5.17' 4.10 5.03 Total Catch (in numbers of fish) 7,738 .3,886 4,741 No. of Fish Kept (11arvest) 4,703 1,575 2,030 No. of Fish Released 3,033 2,311 21711 No. of Fish Caught per Hour 0.93 1.12 1.29 (success) No. of Marylanc, Residents/ Non-residents 818/789 750/187* 565/184 B. EXPANDED TOTALS Total Anglers 56,977 26,291 21,062 Total Hours Fished 291,510 107,530 109,764 Total Harvest 205,280** 48,914 50,432 Total Catch 337,611 N/A 129,611 Trips 56,384 26,226 21,821 *Obtained by taking 80% of anglers interviewed (RMC 1979, p. 3). **Obtained by multiplying the estimated total fish caught by the ratio of numbers of fish kept to total fish caught. ti, t t. 45 TABLE 12. Catch per angler hour for selected species caught during the 1970, 1979 and 1980 Susquehanna River sport Fishing Surveys. 1970 1979 1980 SPECIES CPUB1 CPUE2 CPUE Morone americana 0.3830 0.6912 0.7375 Morone saxatilis 0.0404 0.0517 0.1270 Alosa -pseudoharenclus/. A. aestivalis 0.2609 0.0295 0.0016 Alosa sapadissima 0.0835 0.0043 0.0003 Ictalurus punctatus 0.0593 0.1944 0.1892 1. From Carter 1973. 2. From RMC 1979. J!L TABLE 13. Comparison of the species composition and harvest of finfish caught by sport anglers during the 1979 and 1980 Susquehanna River Sport Fishing Surveys. Estimated Percent of Species No. Kept No.Released Total Caught Harvest Est. Harvest 1979 1980 1979 1980 1979 1980 1979 1980 1979 1980 Morone americana 864 1,051 1,529 1,654 2,393 2,705 26,833 23,739 54.9 47.'1 Ictalurus punctatus 356 276 317 418 673 694 11,056 8,184 22.6 16.2 Ictalurus nebulosus - 120 - 146 - 266 - 3,724 - 7.4 Cyprinus carpio 108 193 96 80 204 273 3,354 3,267' 6.9 6.5 Morone saxatilis 59 278 120 188 179 466 1.832 8,991 3.7 17.8 Alosa P-seudoharengus/ A.,aestivalis (combined) 48 0 54 6 102 6 1,491 0 3.0 0.0 Dorosoma, cepedianum 47 17 56 54 103 71 1,460 265 3.0 o.5 Micropterus; dolomieui 16 33 47 27 63 60 497 601 1.0 1.2 Perca flavescens 14 26 23 50 37 76 435 211 0.9 0.4 Alosa sapidissima 13 0 2 1 15 1 404 0 0.8 0.0 Pomoxis spp. 13 6 8 37 21 43 404 104 0.8 0.2 Lepomis macrochirus 8 11 12 15 20 26 248 535 0.5 1.1 Anguilla rostrata 7 2 25 6 32 8 217 91 0.4 0.2 Other spp. 22 17 22 29 44 46 683 720 1.4 1.4 TOTALS 1,575 2,030 2,311 2,711 3,886 4,741 48,914 50,432 99.9 1100.0 .Conowingo Dam 47 FIGURE V. Interview sites for 1980 Susquehanna Octoraro River Sport Fishing Survey. Creek 05 Deer Creek N 2 3* 0 12 4 1. Shure's Landing !Port Deposit 2. Mouth of Deer Creek 10 9 3. Susquehanna State Park 64-- 4. Lapidum 5. Riverside* 6. Logan's Wharf 7. Penn's Beach 8. Baldwin's Dock 9. Owen's'Fish House 10. Port Deposit Marina OKI 11. Tidewater Marina 12. Spangler's Rock Run 13. Tydings Park Marina Dropped site. -V I I I U S. 40_ 8 ;Perryville Havre-de-Grace *Ai ---.U'S* 40 ;Perryvjl ell ell 7 48 J FIGURE V1. INTERVIEW FORM FOR 1980 SUSQUEHANNA RIVER SPORT FISHING SURVEY. 1. Interviewer Code FIF 1 (1-2) 2. Month/Day/Year (3-8) 3. -Site Code (9-10) 4. Total Number of Anglers Leaving Site (both those interviewed and not interviewed) 5. Interview Number 6. Mode (16) Boat, rod " I Bank, rod = 2 Dipnet =3 7. Number of People in Party (17-18) 8. State of Residence (19-20) Maryland = MD Pennsylvania = PA F Delaware = DL Virginia = VA F District of Columbia = DC F Other = OT t 9. Party Hours Fished (21-22) F t t'jl 49 FIGURE VI, con't. 10. Catch Information: Species Species code (see code sheet) Disposition Kept = I Thrown back = 2 Used for bait = 3 Number of fish for each disposition type Species Species Code Disposition No. of Fish F-1 (23-27) El (28-32). F-1 (33-37) (38-42) F-1 (43-47) (48-52) El (53-57) (58-62) (63-67) (68-72) 11. opinion of Fish Ladder at Conowingo Dam (76) For = 1 Against = 2 Don't care = 3 12. opinion of White Shad Fishing Closure E 1 (80). For= 1. Against = 2 Don't care = 3 50 JOB IV. JUVENILE RECRUITMENT SURVEY INTRODUCTION Numerous authors have noted a possible significant relationship between numbers of juvenile American shad and the numbers of spawning adults three to five years later (Chittenden 1975, Marcy 1976, Minta, Crecco, and Jacobs 1980). Chittenden (1975) investigated year class strengths by studying age.and sex composition data and comparative run sizes for adult populations of Delaware River American shad between 1963 and 1965. He back-calculated by age class to determine the year class IF which exerted the greatest influence on the adult population for a particular year. Marcy (1976) collected juvenile American shad IF from the Connecticut River and calculated their yearly abundance between 1967 and 1973. He then developed an equation which indicated a significant relationship between juvenile shad, adults potentially available to spawn, water temperature, and river flow. Marcy stated that this equation could be successfully used to predict juvenile shad production in a particular year. From data derived by Marcy (1976), Minta, et al. (1980) r regressed the realtive young-of-the-year and adult abundances of Connecticut River American shad and noted a strong positive correlation indicating year class strength is established before Meg the juvenile stage. From further analysis of Marcy's 1965-72 juvenile index data and corresponding numbers of age V virgin females collected between 1970 and 1977, Minta also noted t the apparent influences that the juvenile year classes exerted upon yearly abundances of adult American shad. He concluded that relative young-of-the-year abundances could be a useful management tool in forecasting adult year class strength five years in advance. Management strategies can be developed from a historic data base; therefore, beginning in 1979 an extensive juvenile recruitment survey was initiated in the Susquehanna River, Susquehanna Flats, and Northeast Rivers to provide an adequate 51 juvenile data base for developing management policies for Maryland shad stocks. METHODS AND MATERIALS To measure the spawning success of clupeid spe cies at the head-of-Chesapeake Bay during 1980 a detailed young-of-the-year sampling survey was conducted on the Susquehanna River, Susquehanna Flats, and Portheast River. Sampling was carried out on a bi-weekly schedule from late June through October (Tablel4). Ten shallow water shore sites were sampled with one of two different haul seines during each sampling period. At seven Md locations below Port Deposit, a 2001xlOlxl/2" stretch mesh haul seine was set by boat in a semi-circular shape. The area swept by this seine set was calculated to be 0.0591 hectares. Because of the rocky nature of the Susquehanna River above Port Deposit, the three upper river sites had to be sampled with a 100'x6lxl/2" stretch mesh haul seine. The corresponding area swept by this gear, also set in a semi-circular shape, was calculated to be 0.0148 hectares. Locations and de-scriptions for each seine site can be found in FigureVIIand Table 15, respectively. Six open water sampling stations were established in the Susquehanna Flats and Northeast River as close to their corresponding seine sites as water depths and the presence of bottom snags would permit (Figure VI; Tablel-5). Open water sampling was done with a modified 16' headrope semi-balloon shrimp (otter) trawl with 1/2" stretch mesh open end, 1 1/2" stretch mesh cod end, and 1/2" stretch mesh cod end liner. The area swept by this gear was calculated as: 3.0175 m*x trawl run length (m) = area swept in hectares 10,000 M4 *3.0175 m effective trawl mouth opening 52 Starting and stopping points for each run were determined from compass sightings of nearby fixed shore and navigational structures. Appropriate compass bearings are found in Table 16. Trawl and seine samples were collected nearly simultaneously with replicate seine pulls and trawl runs made at each station per.sampling period except where precluded by inclement weather or equipment failure. Tables 17, 18, 19, and 20 present sampling effort data by site and period for all gear types. RESULTS A total of 182 seine hauls and 101 trawl runs were made at sampling stations on the Susquehanna River, Susquehanna Flats, and Northeast River from 24 June through 31 October 1980. This effort captured 44,321 fish of 33 species (Table 21). Numbers and weights for each species caught by gear type by period and station are presented in Tables, 23through 29. Calculations of standing crop arranged by period and station for each gear type for all species combined are detailed in Tables30, 31, 32, and 33. Of note - 1. Standing crop for haul seine effort was greatest - during,Periods II and VII for number and weight per unit area, respectively - at Station 2 for both number and weight per unit area 2. Standing crop for otter trawl effort was greatest - during Period V for both number and weight per unit area - at Station 2 for both number and weight per unit area 3. For the six common seine and trawl stations mean standing crop - was 49% greater (#/ha) for haul seine vs. otter trawl captures - was 18% greater (kg/ha) for otter trawl vs. haul seine captures 53 4. For the nine common seine and trawl sampling periods mean standing crop - was 40% greater (#/ha) for haul seine vs otter trawl captures - was 39% greater (kg/ha) for otter trawl vs haul seine captures Young-of-the-year catch and catch per unit of effort for four important commercial and sport species, blueback herring (Alosa aestivalis),- alewife herring (Alosa pseudoharengus), striped bass (Morone saxatilis), and whiteperch (Morone americana), by gear type, sampling period, and station are presented in Tables 34 and 35. General trends indicated by this data were: 1. The haul seine caught more juvenile alewife and blueback herring and striped bass than the otter trawl. 2. A large total catch and catch-per-unit-of-effort (CPUE) of young-of-the-year herring and striped bass by one gear type was generally not accompanied by a corresponding large catch by the otner gear type. 3. The haul seine captured young-of-the-year blueback herring, striped bass, and white perch in all sampling periods except X. 4. Of the four species, only juvenile striped bass were captured upstream from Station 6. In the Susquehanna River,standing crop calculations (numbers/ha @J only) by gear type, period, and station for these four species OL are presented in Tables36 and 37. Each of these four species were generally more prevalent during the middle sampling periods. Both young-of-the-year blueback and alewife herring were more abundant at one particular station (Wild Duck Cove and Camp Rodney, respectively) while juvenile striped bass and white perch were concentrated in at least three different sampling locations. No young-of-the-year American or hickory shad were captured during the 1980 Juvenile Recruitment Survey. However, a yearling 54 American shad was captured by otter trawl at Havre de Grace, Station 6 on 22 July 1980. Of the 302 juvenile herring captured by haul seine, 64% (194) were alewife. The.species ratio for otter trawl captures was 58% (38) alewife and 42% (27) blueback herring. Haul seine catches of blueback herring indicated a bi-modal capture distribution, for both total numbers caught and CPUE, with peaks F in Periods I and VII/VIII (FigureVIIT Table34). Following Period I, otter traoil catches of bluebacks, however, were greatly reduced (Figure !X , Table 34) Haul seine and otter trawl catches of alewife herring were concentrated more during the survey's middle periods, peaking in Period V for haul seine and Period VI for otter trawl captures (Figures VIIIand IX , Table 34 Site specificity for haul seine catches of both herring species was also noted (Figures X and XI, Table 35 ) . Station 4 had 66% of all alewife herring haul seine catches while Station 1 had 46% of all blueback herring captured by this gear type. Site specific differences in trend of catch by otter trawl for both 114 species were less obvious due to the small numbers captured, although alewives appeared to be more evenly distributed over the open.water stations than bluebacks. t DISCUSSION No young-of-the-year American shad were captured during the 1980 juven'ile survey. The failure of the two gear types employed to capture any juvenile shad could be due to a number of factors. These include poor sampling techniques (i.e., poor timing, improper sampling locations, etc.), insufficient sampling, and a general recruitment failure. With regard to the first two, poor sampling techniques and inadequate sampling, the sampling design for the 1980 survey was based upon a study carried out in the late 1960's by Carter (1973) in the same Susquehanna region. Carterls conclusions 55 were that the sampling techniques and gear he used were effective in capturing juvenile American shad. Data gathered over the past twenty-two years by the Maryland Estuarine Fish-Recruitmer)t Survey, Federal Aid Project F-27-R-6, show that no young-of-the-year American shad have been captured from any of ten upper Bay stations since 1972 (Boone 1980). Four of these ten sites are located close to four of the 1980 survey sites. Boone found that prior to 1972, juvenile shad were frequently taken by haul seine and tl.at catch.rates had been as high as 17 juveniles per haul during years of good reproduction. During 1980, the Maryland Anadromous Fish Stream Survey Program (AFC-8) conducted extensive sampling in the Susquehanna area with a bow-mounted push trawl. This apparatus, developed by the Virginia Institute of Marine Science has proved successful in collecting Juvenile American shad in Virginia waters (Kriete and Loesch 1980). Push trawl sampling on the Susquehanna was initiated in June and continued through September on a tri-weekly basis. All sampling was conducted at night. No young-of-the-year American shad were collected by this gear during 1980 although two juvenile hickory shad were captured at.Station 4, Port Deposit, during June (MTA infile data). It appears that the 1980 sampling in the Susquehanna region by these various projects was adequate in both technique and IJ magnitude to note the presence of juvenile American shad. mi The lack of juveniles, then, is the result of a near total recruitment failure during the 1980 spawning season. This failure to reproduce may be-the result of certain chemical, physical, and biological conditions, some of which are briefly discussed below. Chemical contaminants from nearby locations and upstream in the Susquehanna watershed may derive from urban non-point source runoff, agricultural runoff,. and sewage treatment plant (STP) discharges, particularly chlorine. Colston (1974) found that COD and BOD from urban non-point sources averaged 91% and 67%, respectively, that of raw sewage. lie also noted that 56 concentrations of heavy metals were from two to fifty times greater than in raw sewage. Increased sedimentation as a@result of greater agricultural and urban land use 'can be highly detrimental jPj to fish eggs. Morgan et al. (1973) found that only 0.5 to 1.0 mm of sediment cover caused greater than 50% mortalities-in white perch eggs and that 1.2 mm of deposited sediment resulted L in 100% mortality. Concerning chlorine, Middaugh et. al. (1977) found that larval development in striped bass, white perch and blueback herring was inhibited by increased chlorine concentrations; the length.of larval fish hatched decreased, and that the incidence t of larval deformities also increased with increases in chlorine '7 1- concentrations. A delay in hatching or a change in the number of eggs hatching or nearing hatch may be very detrimental to a larval population. A delay in hatching may cause changes in the distribution and density of larvae both in time and space, plus a possible desynchronizing of larval food availability. Deformed larvae are less able to capture food or avoid predation. In an attempt to mitigate some of these problems the Maryland Departments 1@" LO of Natural Resources and Health and Mental Hygiene have selected certain STP's in the upper Chesapeake Bay and asked that their chlorine discharges be reduced or eliminated during the spring OR Lj spawning season. A number of biological factors may be adversely affecting American shad reproduction. Contamination of the eggs and milt by pesticides, heavy metals, and PCB's through accumulation in the adults could result in abortion/reabsorption of eggs, production of non-fertile eggs and milt, and deformities in eggs and larvae. During 1979 the Maryland Department of Health and Mental Hygiene analyzed body tissue and gonadal samples from six adult American shad taken from the Ousquehanna River. This testing showed generally low levels of metals, pesticides, or PCB's in either flesh or reproductive organs- (MTA infile data). Also during 1979, in a controlled lab experiment, Susquehanna River shad eggs were artificially fertilized to determine egg viability and hatching success. Examination of both fertilized eggs and developing 57 larvae revealed no discernable physical deformities that suggested gonadal deficiencies. Although these data are not conclusive, they suggest that reproductive organ failure is not the major factor contributing to the lack of recruitment. A second biological factor to consider is the problem of drastically reduced spawning stocks in the upper Bay area. Leggett (1969) estimated that survival for American shad from egg to adult was approximately one in 100,000 indicating tremendous mortality for eggs and larvae. Since 1974 the tch of adult American shad from the Susquehanna area commercial ca dropped precipitously (Table 38) resultingin the closure of the shad fishing season for 1980. The decline in spawning stock size, as indicated by declining commercial catch, was also mirrored by the juvenile survey work of Boone (1980) and this current study. These two trends are strong indications that the number of juveniles produced by the remaining adult stocks in the Susquehanna area are not sufficient to replace individuals lost to both natural and man-induced mortalities. Conowingo Dam at river mile 10 physically affects reproduction of American shad in several ways. 1. The area available for finfish spawning in the Susquehanna River is severely limited. Prior to the 64 dam's completion in 1928, other dams along the river periodically restricted shad migration which historically had been as far as Binghamton,*New York at river mile 218. By contrast, the Connecticut River with fish passage facilities at both Holyoke and Turners Falls Dams has 120 miles of river open for spawning, while the Delaware has approximately 270 river miles. available. 2. Conowingo Dam.is designed as a peaking plant, with the volume of water discharged constantly changing depending upon power demand and available water. Because 58 of this change in demand water depths may fluctuate as much as 15 feet while river flow may range from 0 to 86,000 cfs. These drastic fluctuations create unstable and unsuitable spawning habitat and conditions. Also, reduced flows have led todissolved oxygen deplettons which have resulted in four major fish kills and numerous minor ones below the dam since 1965. Either of these conditions could be caus ative factors in the reproductive failure of American shad in the Susquehanna Region and because,of the possible interrelationships behind them elimination of one may not solve this problem. During 1979,a preliminary juvenile recruitment survey was conducted in the head-of-the-Bay region with haul seine only. This sampling utilized the same ten stations as the 1980 survey, with each station being checked every two weeks. The 1979 survey, however, encompassed only six sampling periods, resulting in 115 seine hauls or 67 less than the following year. All other sampling techniques and equipment were identical for both year's work. Results of the 1979 survey appear in Tables39 through 44. The 1979 seine survey captured three juvenile American shad during the six sampling periods. Young-of-the-year were captured at the Cara Cove (#3) and the Camp Rodney (#4) stations on 7/24/79 and at the Robert Island station (#9) on 8/24/79. Catch per.haul was calculated as 0.03. No juvenile American shad were captured during the 1980 survey. Catch in 1980 of ju venile blueback and alewife herring was markedly different from the 1979 catch. The total seine catch of alewife in 1980 was 194 as compared to only 18 in 1979, a 10.4 fold increase. Ca-11-ch per-seine haul in 1980 was 1.07 as opposed to only 0.16 in 1979, a 669% increase. For bluebacks, however, the total catch and catch per haul decreased in 1980; total catch was down by 244 individuals (326%) and catch per haul was down from 3.06 to 0.59 fish per haul, a five fold decrease. The large increase in the alewife 59 herring juvenile CPUE in 1980 could have been due to the increase in numbers of yoy over 1979 (Tables 43 and 44). Total catch and catch per unit effort for juvenile striped 1.4 bass was down in 1980, with 33% fewer juveniles being captured. Catch by site for both numbers and rate were greatest at Station 1 during both years. Data for juvenile white perch captures (Tables43 and 44) indicated that even though 672 more young-of-the-year were takenin 1980, catch per haul in 1979 was 21.3 while catch per haul for 1980 was 22.1. This indicated similar young-of-the-year populations in both years. The greatest numbers were captured from late August until the end of the survey during both years. Similarity in juvenile captures by site was also noted for the two years with the greatest numbers and highest rates occurring at Station 2. Data gathered by Carter (1973) in 1968 and 1969 provides an adequate data base from which to note changes in the clupeid catch. J Procedures and techniques used by Carter for his earlier survey were utilized during 1980. Of the 12 sites sampled in 1968-69, seven sites were resurveyed in 1980. These common sites are listed below: NAME SITE CODE 68-69 1980 Wild Duck Cove 12 1 Seneca Point 9 2 Cara Cove 8 3 Camp Rodney 7 4 Fishing Battery 3 5 Tydings Park 2 6 Quarry 1* 7* *haul seine only@. Summation and comparison of the seven common sampling stations for the two surveys noted t;iat- 60 1. Additional computations from Carter 1973, Table 53, page 61, indicated that a total of 281 young-of-the-year shad were captured by haul seine in 1969* and that 95 were collected by otter trawl during 1968/1969. During this study, juvenile shad were taken by haul seine at two sampling stations, Cara Cove and the Quarry. Otter trawl captures of young-of-the-year American shad for 1968/1969** were from four different locations; Cara Cove, Camp Rodney, Battery Island, and Tydings Park. EstillLates for standing crop of juvenile shad by gear type derived from Carter (1973, Table 53, page 61) were 103/ha for haul seine and 4/ha for otter trawl samplings. No juvenile American shad were captured during 1980. 2. During the 1968 and 1969 samplings (Carter, 1973, Table 53, page 61) a total of 233 and 1,476 young-of-the-year alewife herring were captured by haul seine and otter trawl, respectively. Alewife herring were captured at five of the seven seine sites and at all six otter trawl stations. Standing.crop, derived from Carter's data (Table 53, page 61) for alewives was calculated to be 86/ha for haul seine in 1969 and 66/ha for otter trawl captures during 1968/1969. In 1980, 194 and 38 juvenile alewife herring were collected by the same two gear types respectively. Calculated standing crop for haul seine was 23/ha and 1.4/ha for otter trawl. During 1980 this species was collected at four sites by seine and at five sites by trawl. haul seine data for 1969 only 1968 and 1969 otter trawl data combined 61 3. For blueback herring, Carter (1973, Table 53, page 61) collected a total of 5,281 by haul seine in 1969 and 520 by otter trawl for both years combined. Bluebacks were collected at all surveyed stations by both gear types during the earlier survey. Standing crops calculated for the 1969 seine haul captures was 1,944/ha and 23/ha for the 1968/1969 otter trawl. The 1980 seine sampling captured 108 young-of-the-year blueback herring from five cifferent stations while the otter trawl collected 27 from three separate sites. Numbers per hectare in 1980 were calculated to be 13 and 1 for haul seine and otter trawl captures, respectively. Comparisons of the results of these two surveys indicate a drastic decline in abundance of American shad, alewife and blueback herring during the 1970s (Table 45). The magnitude and severity of this decline is also mirrored by the commercial catch of these three species from the Northeast and Susquehanna Rivers and the Susquehanna Flats combined for the previous 12 years (Table 38). The numbers of American*shad upper bay brood stock may continue to decrease simply because there are not enough recruits to replace dying adults. This condition will necessitate further intensive management to insure that the number of mature adults does not fall below a level where natural recovery is impossible, a level that may have already been attained. SUMMARY 1. One hundred eighty-two. seine hauls and 101 trawl runs were made at 10 seine and six trawl stations on the Susquehanna River/Flats and Northeast River. There were 44,321 fish of 35 species captured. 2. No young-of-the-year American shad were captured in 1980. 3. Among the 35 species captured, juveniles from four important commercial and sport species were represented; Iola blueba ck and alewife herrings, striped bass, and white perch. 62 4. Comparisons with previous studies indicate drastic declines in total numbers and standing crop of juvenile American shad and alewife and blueback herrings in the Head-of-the-Bay between the late 1960's through 1980. 63 TABLE 14. Sampling periods during the 1980 Juvenile Recruitment Survey. SAMPLING PERIOD DATES Period I June 23, 24, 25, July 1 Period II July 7, 11, 12 Period III July 21, 22, 23 Period IV August 4, 5, 6 Period V August 18, 19, 20 Period Vi September 2, 3, 4 Period VII September 17, 18, 19 Period VIII October 1, 2, 3 Period Ix October 15, 16, 17 Period X October 30, 31 64 TABLE Station numbers, names, locations, and mode of sampling during the 1980 Juvenile Recruitment Survey. STATION SAMPLING MODE LOCATION No. Name F 1 Wild Duck Cove seine & trawl Susquehanna Flats 2 Seneca Point seine & trawl Northeast River F. 3 Cara Cove seine & trawl Northeast River 4 Camp Rodney seine & trawl Susquehanna Flats 5 Battery Island trawl only Spoil Island #1 seine only Susquehanna Flats 6 Tydings Park seine & trawl Susquehanna Flats 7 Quarry seine only Susquehanna River F1 8 Spencer Island seine only Susquehanna River 9 Robert Island seine only Susquehanna River 10 Spangler's Rock Run seine only Susquehanna River t t t F1 TABLE 16 Trawl station number, name, location, and compass bearings 1during the 1980 Juvenile Recruitment Survey. SITE STATION NAME & LOCATION COMPASS BEARINGS (in degrees magnetic) Point of Reference Start Finish 1 Wild Duck Cove, Susq. Flats Stump Pt. water tank 290 290 Concord Pt. Lighthouse 274 272 Carpenter Point 155 136 2 Seneca Pt., Northeast River Microwave Tower 96 102 311 Fire Tower 132 140 Carpenter Point 205 218 3 Cara Cove, Northeast River Red Flasher #6 264 222 Red Marker #8 352 40 Black Can #7 305 258 Microwave Tower 60 311 Fire Tower 110 @4 Camp Rodney, Susq. Flats Red Nun #4 12 257 Red Cha'nnel Marker #2 210 206 5 Battery Island, Susq. Flats Plum Pt. water tank 264 252 Concord Pt. Lighthouse 7 12 6 Tydings Park, Susq. Flats Concord Pt. Lighthouse 4 355 Perryville Elev. water tank 33 39 Black Can #15 190 192 1. Refer to NOAA National Ocean Survey Chart #12274, "Head of Chesapeake Bay" L-- EJ Pl- E- LL'' LL-, L" L] 66 TABLE 17. Number of seine hauls and trawl runs by period and site during the 1980 Juvenile Recruitment Survey. A. Effort By Period No. of Hauls/Runs by Period Period I II III IV V VI VII VIII Ix x seine 20 20 20 20 20 20 18 18 18 14 trawl 12 11 11 9 12 12 11 11 12 0 B. Effort By Site No. of Hauls/Runs by Site Site 1 2 3 4 5 6 7 8 9 10 seine 20 20 20 20 20 20 20 10 16 16 trawl 17 18 17 13 18 18 0 0 0 0 67 TABLE Number of hauls and area swept by haul seine for each sampling period during the 1980 Juvenile Recruitment Survey. LOCATION NO. OF HAULS AREA SWEPT/HAUL TOTAL AREA SWEPT (hectares) (hectares) eriod 1 14 0.0591* 6 0.0148** 0.9162 Period 11 14 0.0591 0 0.0148 0.8274 Period 111 14 0.0591 6 0.0148 0.9162 Period IV 14 0.0591 6 0.0148 0.9162 Period V 14 0.0591 6 0.0148 0.9162 Period VI 14 0.0591 6 0.0148 0.9162 Period VII 14 0.0591 4 0.0148 0.8866 Period VIII 14 .0.0591 4 0.0148 0.8866 Period IX 14 0.0591 4 0.0148 0.8866@ Period X 14 0.0591 0 0.0148 0.8274 Total 8.8956 area swept by 200 ft. seine area swept by 100 ft. seine 1!11L NIR .I.'i@@ TABLE 19. Area swept by otter trawl for each sampling period by site during the 1980 Juvenile Recruitment Survey. AREA SWEPT BY SITE TOTAL AREA (ha) SWEPT (ha) PERIOD 1 2 3 4 5 6 0.4414 0.4690 0.5518 0.6070 0.5518 0.5518 3.1728 0.4414 0.4690 0.5518 0.3035 0.5518 0.5518 2.1728 0.2207 0.4690 0.5518 0.6070 0.5518 0.5518 2.9521 IV 0.4414 0.4690 0.2759 0.0000 0.5518 0.5518 2.2899 V 0.4414 0.4690 0.5518 0.6070 0.5518 0.5518 3.1728 VI 0.4414 0.4690 0.5518 0.6070 0.5518 0.5518 3.1728 VII 0.4414 0.4690 0.5518 0.3035 0.5518 0.5518 2.8693 VIII 0.4414 0.4690 0.5518 0.3035 0.5518 0.5518 2.8693 Ix 0.4414 0.4690 0.5518 0.6070 0.5518 0.5518 3.1728 x TOTAL 26.5411 a% Co 69 TABLE 20 Area swept by haul seine and otter trawl, number of - hauls taken and trawl runs completed, and total area swept by site during the 1980 Juvenile Recruitment Survey. LOCATION NO. OF HAULS AREA SWEPT TOTAL AREA (ha) SWEPT (ha) A. Haul Seine Site 1 20 0.0591 1.1820 Site 2 20 0.0591 1.1820 Site 3 20 0.0591 1.1820 Site 4 20 0.0591 1.1820 Site 5 20 0.0591 1.1820 Site 6 20 0.0591 1.18.20 6J Site 7 20 0.0591 J.1820 Site 8 10 0.0148 0.1480 Site 9 16 0.0148 0.2368 Site 10 16 0.0148 0.2369 TOTAL 8.8956 B.@ Otter Trawl Site 1 17 0.2207 3.7519 hJ Site 2 18 0.2345 4.2210 Site 3 17 0.2759 4.6903 Site 4 13 0.3035 3.9455 Site 5 18 0.2759 4.9662 Site 6 18 0.2759 4.9662 TOTAL 26.5411 70 TABLE 21. Species caught during the 1980 Juvenile Recruitment Survey. SCIENTIFIC NAME COMMON NAME Alosa aestivalis Blueback herring Alosa pseudoharengus Alewife herring Alsoa sapidissima American shad Anchoa mitchilli Bay anchovy Anguilla rostrata American eel Brevoortia tyrannus Atlantic menhaden Carassius auratus Goldfish Carpiodes cyprinus Quillback Cyprinus carpio Carp Dorosoma cepedianum Gizzard shad Etheostoma olmstedi Tesselated darter Fundulus diaphanus Banded killifish Fundulus heteroclitus Mummichog Hybognathus nuchalis Silvery minnow Hypentilium, nigricans Northern hogsucker Ictalurus nebulosus Brown bullhead Ictalurus punctatus Channel catfish Leiostomus xanthurus Spot Lepomis auritus Redbreasted sunfish Lepomis gibbosus Pumpkinseed Lepomis macrochirus Bluegill Lepomis megalotis Longear sunfish 71 TABLE 21 -, con't. SCIENTIFIC NAME COMMON NAME Membras martinica Rough silverside Menidia beryllina Tidewater silverside Microptr@rus dolomieui Smallmouth bass Micropterus salmoides Largemouth bass Morone americana White perch Morone saxatilis Striped bass Notropis hudsonius Spottail shiner Notropis spilopterus Spotfin shiner kJ Perca flavescens Yellow perch Pomatomus saltatrix Bluefish Pomoxis nigromaculatus Black crappie Strongy1ura marina Atlantic needlefish Trinectes maculatus Hogchoker TABLE 22. Species and numbers of individual finfish collected by haul seine during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS III IV V Vi. VII VIII Ix x Alosa aestivalis 21 9 5 1 3 6 16 25 2 108 A-Eo--sa pseudoharengus 3 27 39 38 46 36 18 7 214 Alosa sapidissima 0 Anchoa mitc-hilli-'- 2 3 21 181 4 2 213 Anguilla rostrata 3 3 6 2 3 8 2 3 30 Brevoortia tyrannus 2,097 588 252 227 40 755 986 74 328 5,347 @@-a-rassius auratus 0 Carpiodes cyprinus 0 Cyprinus carpio 4 6 1 4 2 5 1 23 Dorosoma cepedianum 4 5 44 101 1,051 35, 246 214 31 981 2,712 Etheostoma olmstedi 1 3 9 6 14 36 10 79 Fundulus diaphanus 4 1 36. 7 10 5 4 67 Fundulus heteroclitus 2 12 4 11 4 2 3 38 Hybognathus nuchalis 1 2 1 4 Hypentelium nigricans 1 1 1 .3 Ictalurus nebulosus 1 1 Ictalurus punctatus 4 8 5 13 8 44 8 3 2 95 Leiostomus xanthurus 1 2 5 71 13 55 87 234 Lepomis auritus, 2 2 Lepomis gibbosus 3 9 6 9 14 2 9 52 Lepomis macrochirus 1 17 1 8 1 28 Lepomis megalotis 2 1 3 Membras martinica 46 3 1 2 12 3 67 Menidia beryllina 71 42 23 15 8 60 170 160 44 56 649 Micropterus dolomieui 5 4 5 4 18 Micropterus salmoides 1 2 2 5 Morone americana 657 220 409 289 299 746 347 317 79 73 3,436 Morone saxatilis 1 12 5 5 16 11 21 4 1 76 TABLE 22 con' t. SPECIES SAMPLING PERIODS TOTALS I II III IV V VI VII VIII Ix x Notropis hudsonius 173 69 94 164 335 384 433 421 123 176 2,372 Notropis spilopterus 8 8 Perca flavescens 8 10 14 12 18 6 37 24 9 17 155 Pomatomus saltatrix 1 1 Pomoxis nigromaculatus 2 1 1 4 Strongylura marina 2 2 4 Trinectes maculatus 1 2 5 1 9 TOTALS Species 18 19 22 20 24 19 22 is 13 12 32/ Numbers 1,012 2,533 1,263 924 2,149 1,456 1,178 2,476 412 1,653 16,057 L- U E- LLL: LL,,@ L Ll nwk,4 ow- NMI,. Wqn OR- TABLE 23. Species and numbers of individual finfish collected by otter trawl during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS I II III IV V VI VII VIII Ix x Alosa aestivalis 24 1 2 27 Alosa pseudoharengus 6 1 3 7 11 12 2 2 22 @@-losa sapidissima 1 1 Anchoa mitchilli 50 35 75 5 166 Anguilla rostrata 85 6 35 4 130 Brevoortia tyrannus 38 15 15 1 1 5 5 22 24 120 Carassius auratus 1 1 Carpiodes cyprinus 2 2 Cyprinus carpio 19 9 17 5 5 3 2 2 2 64 Dorosoma cepedianum 2 17 72 207 71 64 28 461 Etheostoma olmstedi 1 1 2 1 3 6 5 19 Fundulus diaphanus 0 Fundulus heteroclitus 0 Hybognathus nuchalis 0 Hypenteli nigricans 1 1 Ictalurus nebulosus 6 15 5 1 3 1 3 34 Ictalurus punctatus 35 58 130 20 129 199 206 25 26 828 Leiostomus xanthurus 16 160 31 548 144 422 459 183 1,963 Lepomis auritus 0 Lepomis gibbosus 1. 3 1 1 1 1 1 9 Lepomis macrochirus 0 Lepomis megalotis 0 Membras martinica 0-' Menidia beryllina 0 Micropterus dolomieui 0 Micropterus salmoides 0 Morone americana 1,751 3,710 3,468 2,635 4,091 2,417 3,052 1,190 432 22,746 Morone saxatilis 3 12 3 1 3 4 1 5 2 34 TABLE 2 3 con't. SPECIES SAMPLING PERIODS TOTALS I II III IV V vi VII VIII Ix x Notropis hudsonius 205 223 60 56 64 75 90 84 18 875 Notropis spilppterus 0 Perca flavescens 89 64 58 44 41 15 32 27 54 424 Pomatomus saltatrix 0 Strongylura marina 0 Trinectes maculatus 2 6 31 44 42 164 10 10 309 TOTALS Species 13 16 17 13 15 15 15 15 12 21/ Numbers 2,264 4,141 3,992 2,820 5,069 3,161 4,127 1,905 785 28,264 F" IL .9, L @. w"- - 0% - TABLE 24. Species and number of individual finfish collected by haul seine at ten sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 50 23 13 8 9 108 Alosa pseudoharengus 53 2 30 120 214 Alosa sapidissima 0 Anchoa mitchilli 176 19 12 4 1 1 213 Anguilla rostrata 3 6 7 12 1 1 30 Brevoortia tyrannus 602 1,484 1,216 1,897 148 5,347 Carassius auratus 0 Carpiodes cyprinug 0 Cyprinus carpio 3 4 4 9 1 1 1 23 Dorosoma cepedianum 121 1,353 193 51 288- 60 646 2,712 Etheostoma olmstedi 16 16 10 6 4 26 1 79 Fundulus diaphanus 20 23 1 14 15 4 67 Fundulus heteroclitus .5 2 2 20 8 1 38 Hybognathus nuchalis 1 1 1 1 4 Hypentelium nigricans 3 3 Ictalurus nebulosus 1 1 Ictalurus punctatus 1 35 36 15 2 3 3 95 Leiostomus xanthurus 22 35 14 11 53 99 234 Lepomis auritus 2 2 Lepomis gibbosus 8 4 1 11 5 13 10 52 Lepomis macrochirus 1 1 1 12 4 9 28 Lepomis megalotis 1 2 3 Membras martinica 1 54 12 67 Menidia beryllina 89 54 48 98 114 179 66 1 649 Micropterus dolomieui 1 8. 4 5 18 Micropterus salmoides 3 2 5 Morone americana 313 914 438 1,128 302 325 15 1 3,436 Morone saxatilis 15 8 7 16 7 12 11 76 TABLE 24 con't. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Notropis hudsonius 603 290 283 430 313 234 215 4 2,372 Notropis spilopterus 4 4 8 Perca flavescens 13 19 33 31 5 27 @20 6 1 155 Pomatomus saltatrix 1 1 Pomoxis nigromaculatus 3 1 4 Strongylura marina 2 4 Trinectes maculatus 7 2 9 TOTALS Species 18 - 20 18 20 18 19 18 8 7 7 32/ Numbers 2,096 4,298 2,360 3,853 1,337 1,008 1,003 40 29 33 16,057 fL TABLE 25. Species and number of individual finfish collected by otter trawl at six sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 6 20 1 27 Alosa pseudoharengus 12 9 3 9 11 44 Alosa sapidissima 1 1 Anchoa mitchilli 17 26 4 49 70 166 Anguilla rostrata 1 10 112 6 1 130 Brevoortia tyrannus 15 43 39 2 27 126 Carassius auratus 1 1 Carpiodes cyprinus 1 1 2 Cyprinus carpio 4 8 18 7 11 16 64 Dorosoma cepedianum 17 224 194 3 3 20 461 Etheostoma olmstedi 9 3 1 2 4 19 Fundulus diaphanus 0 Fundulus heteroclitus 0 Hybognathus, nuchalis 0 Hypentelium nigricans 1 1 Ictalurus nebulosus 28 4 2 34 Ictalurus punctatus 24 73 94 468 46 123 828 Leiostomus xanthurus 410 291 249 277 519 217 1,963 Lepomis auritus; 0 Lepomis gibbosus 7 1 1 9 Lepomis macrochirus 0 Lepomis megalotis 0 Membras martinica 0 Menidia beryllina 0 Micropterus dolomieui 0 Wi-cropterus salmoides 0 Morone americana 3,395 6,024 5,935 2,042 2,6q2 2,658 22,746 co Morone saxatilis 2 2 1 2 10 17 34 TABLE 2 5 con SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Notropis hudsonius 20,0 84 252 68 95 176 875 Notropis spilopterus 0 Perca flavescens 60 178 122 9 29 26 424 Pomatomus saltatrix 0 Pomoxis nigromaculatus 0 Strongylura marina 0 Trinectes maculatus 21 4 17 233 12 22 309 TOTALS Species 17- 17 15 15 14 15 21/ Numbers 4,195 7,028 7,046 3,127 3,508 3,360 28,264 W Wj "IR, RM TABLE 26. Species and weight (grams) of finfish collected by haul seine during ten sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS I II III IV V VI VII VIII Ix x Alosa aestivalis 21 10 5 1 6 17 91 69 6 226 Alosa pseudoharengus 34 345 200 218 375 285 125 46 1,630 Alosa sapidissima Anchoa mitchilli 9 4 21 214 4 2 254 Anguilla rostrata 48 80 105 22 62 209 46. 66 638 Brevoortia tyrannus 7,638 3,516 2,601 2,294 613 10,757 13,020 1,000 9P40 50,479 Carassius auratus 0 Carpiodes cyprinus 0 Cyprinus carp 9,200 8,600 11,000 8,400 1,800 40,000 Dorosoma cepedianum 1,450 530 534 900 12,194 298 4,836 2,278 220 15,149 38,389 Etheostoma olmstedi 1 4 25 16 36 103 25 210 Fundulus diaphanus 12 2 154 35 41 22 15 281 Fundulus heteroclitus 9 50 26 60 18 4 7 174 Hybognathus nuchalis 34 10 62 Hypentelium nigricans 134 128 265 527 Ictalurus nebulosus 230 230 Ictalurus punctatus 486 2,090 478 27 242 365 27 12 9 3,736 Leiostomus xanthurus 12 47 138 1,437 409 1,162 1,961 5,166 E6`pomis auritus 168 168 Lepomis gibbosus 115 427 360 442 480 223 429 2,476 Lepomis macrochirus 81 223 2 57 5 j73 Lepomis megalotis 109 72 181 Membras martinica 180 14 3 10 60 15 282 Menidia beryllina 213 106 62 30 13 154 294- 277 78 98 1,325 Micropterug dolomieui 272 280 185 317 .1,054 Micropterus salmoides 94 4 102 200 Morone americana 14,095 4,253 6,737 2,694 3,943 8,226 5,046 3,107 575 862 49,538 R-o-rone saxatilis- 18 510 14 33 152 107 160 58 8 1,060 co C@ TABLE 26 , con't. SPECIES SAMPLING PERIODS TOTALS I II III IV V vi VII VIII Ix x Notropis hudsonius 2,790 684 483 501 2,199 2,090 2,207 3,351 606 1,173 16,084 Notropis spilopterus 52 52 Perca flavescens 283 245 461 211 588 116 923 474 171 586 4,058 Pomatomus saltatrix 140 140 Pomoxis nigromaculatus 90 44 100 234- Strongylura marina 19 - 19 Trinectes maculatus 1 5 10 2 26 44, TOTALS Species 18 19 22 20 24 19 22 20 13 12 32/ Numbers 28,922 25,468 13,706 8,447 35,696 13,599 35@,947 27,635 2,806 27,064 219,290 Co Im. - rmn "M @n TABLE 27. Species and weight (grams) of finfish collected by otter trawl during nine sampling periods from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS I II III IV V VI VII VIII Ix Alosa aestivalis 28 3 11 42 Alosa pseudoharengus 74 3 30 46 97 102 19 16 387 Alosa sapidissima 70 70 Anchoa mitchilli 3 147 29 52 5 236 Anguilla rostrata, 6,520 278 1,624 281 8,703 Brevoortia tyrannus. 151 68 81 5 16 45 40 336 315 1,057 Carassius auratus' 750 750 Carpiodes cyprinus 1,500 1,500 Cyprinus carpio 37,250 1,300 26,850 8,400 13,200 3,800 7,300 2,500 4,400 105,000 Dorosoma cepedianum 14 135 687 1,155 951 1,030 -745 4,717 Etheostoma, olmstedi 3 4 12 2 12 18 12 63 Fundulus dia2hanus 0 Fundulus heteroclitus 0 Hybognathus nuchalis 0 Hypentelium nigricans 104 104 Ictalurus nebulosus 650 1,552 322 310 245 86 332 3,497 Ictalurus punctatus 2,283 4,204 9,664 1,085 6,705 4,207 6,795 2,023 2,350 39,316 Leiostomus xanthurus 363 2,013 774 10,866 3,130 11,594 11,695 4,059 44,494 Lepomis autitus Lepomis.gibbosu 65 109 35 38 35 36 55 373 Lepomis macrochirus Lepomis megalotis Membras martinica Menidia beryllina. Micropterus dolomieui Micropterus salmoides Morone americana 34,332 8Z408 85,806 83,89+56,316 79,'108 89,515 27,759 1.0,111 649t3OO Morone saxatilis 37 163 -210 93 37 132 138 307 75 TABLE 27 con' t. SPECIES SAMPLING PERIODS TOTALS I II III IV V VI VII VIII Ix Notropis hudsonius 1,812 2,359 753 690 663 586 1,043 1,056 --152 9,114 Notropis spilopterus 0 Perca flavescens 2,000 1,243 2,297 672 966 294 653 750.1,323 10,198 Pomatomus saltatrix 0 Pomoxis nigromaculatus 0 Strongylura marina 0 Trinectes maculatus 33 38 244 497 225 4,740 80 236 6,093 TOTALS Species 13 16 17 13 15 15 15 15 12 Numbers 85,285 94,844 131,516 96,12@190,735 92,939122,991 47,943 23,833 00 IL L-, L- LL@ IL ll@ TABLE 28. Species and weights (grams) of finfish collected by haul seine at ten sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 131 52 25 9 9 226 Alosa pseudoharengus 616 17 159 838 1,630 Alosa sapidissima 0 Anchoa mitchilli 210 19 19 4 1 1 254 Anguilla rostrata 50 141 143 239 6 9 638 Brevoortia tyraEn--us 4,974 21,875 10,454 11,651 1,525 50,479 Carassius auratus 0 Carpioaes cyprinus 0 Cyprinus carpio 3,400 14,400 4,450 11,750 1,300 4,700 40,000 Dorosoma cepedianum 2,196 17,090 2,670 249 2,090 841 13,253 38,389 Etheostoma olmstedi 42 40 24 15 9 78 2 210 Fundulus diaphanus 47 73 2 83 67 9 281 Fundulus heteroclitus 13 10. 7 97 45 2 174 Hybognathus nuchalis 19 18 10 15 62 Hypentelium nigricans 527 527 Ictalurus nebulosus 230 230 Ictalurus punctatus 28 799 376 2,193 3 80 257 3,736 Leiostomus xanthurus 706 706 540 292 837 2,085 5,166 Lepomis auritus 168 168 Lepomis gibbosus 342 294 8 373 203 706 550 2,476 f-ep-om@is macrochirus 1 2 5 104 8 253 3 73 Lepomis megalotis 72 l0q 181 Membras martinica 8 214 60 282 ffe--n=dia beryllina 146 80 97 183 290 378 148 3 1,325 M@c-ropterus dolomieui 1 109 495 449- 1,054 Micropterus salmoides .196 4 200 Morone americana 3,985 10,720 6,199 19,416 4,261 4,452 459 46 49,538 00 Morone saxatilis 77 117 80 107 89 532 58 1,060 4@- ; W'.-: qw-:@ RE Irk TABLE 28. Species and weights (grams) of finfish collected by haul seine at ten sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 131 52 25 9 9 2-26 Alosa pseudoharengus 616 17 159 838 1,630 ,E@-losa sapidissima 0 Anchoa mitchilli 210 19 19 4 1 1 254 Anguilla rostrata 50 141 143 239 6 9 638 Brevoortia tyrannus 4,974 21,875 10,454 11,651 1,525 50,479 Carassiii-s-auratus 0 Carpiodes cyprinus 0 Cyprinus carpio 3,400 14,400 4,450 11,750 1,300 4,700 40,000 Dorosoma cepedianum. 2,196 17,090 2,670 249 2,090 841 13,253 38,389 Etheostoma olmstedi 42 40 24 15 9 78 .2 210 Fundulus diaphanus 47 73 2 83 67 9 281 Fundulus heteroclitus 13 10 7 97 45 2 174 Hybognathus nuchalis 19 18 10 15 62 Hypentelium n' 527 12Eicans 527 Ictalurus; nebulosus 230 230 Ictalurus punctatus 28 799 376 2,193 3 80 257 3,736 Leiostomus xanthurus 706 706 540 292 837 2,085 5,166 Lepomis auritus 168 168 Lepomis gibbosus 342 294 8 373 203 706 550 2,476 Lepomis macrochirus 1 2 5 104 8 253 3 '73 Lepomis megalotis 72 109 181 Membras martinica 8 214 60 282 Menidia 'beryllina 146 80 97 183 290 378 148 3 1,325 Micropterus dolomieui 1 109. 495 449- 1,054 Micropterus salmoides 196 4 200 Morone americana 3,985 10,720 6,199 19,416 4,261 4,452 459 46 49,538 co Morone saxatilis 77 117 80 107 89 532 58 1,060 TABLE 2 8 , con t. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Notropis hudsonius 4,999 2, 266 1,549 3,278 1,566 1,347 1,075 4 16,084 Notropis spilopterus 37 15 52 Perca flavescens 212 292 685 753 128 739 827 385 32 4,058 Pomatomus saltatrix 140 140 Pomoxis nigromaculatus 190 44 234 Strongylura marina 19 19 Trinectes maculatus 13 8 18 5 44 TOTALS Species 18 20 18 20 18 19 18 8 7 7 32/ Numbers 21,840 68,924 27,820 51,489 11,456 1Z045 21r465 995 1,470 1,786 219,@90 00 L WIR WE, wk@@ W,- RE IP--: or-- W-F- IP,-. MEN- TABLE 29. Species and weights (grams) of finfish collected by otter trawl at six sampling stations from 23 June through 31 October for the 1980 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 12 29 1 42 Alosa 2seudoharengus 98 45 80 59 105 387 Alosa sapidissima 70 70 Anchoa mitchilli 19 30 7 127 53 236 Anguilla rostrata 45 573 7,869 211 5 8,703 Brevoortia tyrannus 105 199 325 28 400 1,057 Carassius auratus 750 750 Carpiodes cyprinus . 1,500 1,500 Cyprinus carplo 6,100 11,400 32,050 14,350 17,450 23,650 105 '000 Dorosoma' ZTepedianum 177 1,667 2,190 46 80 557 4,717 Etheostoma olmstedi 23 12 4 6 -18 63 Fundulus diaphanusf 0 Fundulus heteroclitus 0 ,Hybognathus nuchalis 0 Hypentelium nigricans 104 104 Ictalurus nebulosus 2,800 362 335 3,497 Ictalurus punctatus 1,476 4,207 8,599 17,956 2,303 4,775 39,316 Leiostomus xanthurus 8,491 7,230 6,163 5,882 11,119 5,609 44,494 Lepomis auritus 0 Lepomi-s gibbosus 272 65 36 -373 Lepomis macrochirus 0 Lepomis megalotis 0 Membras martinica 0 ff e, -nid i aberyllina 0 MicropEerus dolomieui 0 Micropterus salmoides 0 co Morone americana 87,92A176,190 158,845 63,239 74,364 88,735 649,300 Morone saxatilis 244 54 28 27 327 512 1,192 TABLE 29 con't. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Notropis hudsonius 2,090 737 2,622 .645 964 2,056 9,114 Notorpis spilopterus 0 Perca flavescens 1,011 3,444 3,187 364 1,474 718 10,198 Pomatomus saltatrix 0 Pomoxis nigromaculatus 0 Strongylura marina 0 Trinectes maculatus 391 48 99 5,249 57 249 6,093 TOTALS Species 17 17 15 15 14 14 21/ Numbers 109,06A210,165 222,6161-108,151109,07A127,130 886,206 Co tj (L- 88 TABLE 30 Total numbers collected, total area swept, and standing crop in numbers per hectare for all species combined for each gear typeby sampling period during the 1980 Juvenile Recruitment Survey. F ir PERIOD TOTAL NUMBERS COLLECTED NUMBERS/HECTARE F Seine Trawl Seine Trawl 1.,012 2,264 1,104.6 713.6 11 2,533 4,141 3.,061.4 1,443.2 111 1,264 3,992 1,379.6 1,352.3 IV 924 2,821 1,008.5 1,231.9 V .2,149 5,058 2,345.6 1,594.2 VI 1,456 3',161 1,589.2 996.3 VII 2,178 4,127 2,456.7 1,438.3 VIII 2,476 1,905 2,790.4 663.9 F Ix 412 785 464.7 247.4 x 1,652 - 1,996.6 - F TOTALS 16,057 28,264 Md 89 TABLE 31. Total area swept, total weight of species collected, and standing crop in kiloqrams per hectare for all species combined for each gear type by period during the 1980 Juvenile Recruitment Survey. PERIOD TOTAL WEIGHT (kg) KILOGRAMS/HECTARE Seine Trawl Seine Trawl 1 28.922 85.285 31.567 26.880 11 25.468 94.844 30.780 33.054 111 13.706 131.516 14.959 44.549 IV 8.447 96.120 9.219 41.975 V 35.696 190.735 38.960 60.115' VI 13.599 92.939 14.842 29.292 VII 35.947 122.991 40.544 42.864 VIII 27.635 47.943 31.169 16.708 Ix 2.806 23.833 3.167 7.511 x 27.064 - 32.709 TOTALS 219.290 886.206 wad 90 TABLE 32 Total numbers collec ted, total area swept, and standing crop in numbers per hectare for all species combined for each gear type by station during the 1980 Juvenile Recruitment Survey. STATION TOTAL NUMBERS COLLECTED. NUMBERS/HECTARE Seine Trawl Seine Trawl 1 2,095 4,195 1,772.4 1,118.1 2 4,298 7,028 3 636.2 1,665.0 3 2,360 7,046. 1,996.6 1,502.2 4 3JI853 3,127 3,259.7 792.5 5 1,337 3,508 1 131.1 706.4 6 1,008 3,360 852.8 676.6 7 1,003 847.7 - 8 40 270.3 9 29 122.5 10 33 - 139.4 TOTALS 16,057 28,264 91 TABLE Total area swept, total weight of species collected, and standing crop in kilograms per hectare for.all soecies combined for each gear type by station during the 1980 Juvenile Recruitment Survey. STATION TOTAL WEIGHT (kg) KILOGRAMS/HECTARE Seine Trawl Seine Trawl 1 21.840 109.063 18.477 29.068 2 68.924 210.165 58.311 49.790 27.820 222.616 25.536 47.463 4 51.489 106.155 43.560 27.412 5 11.456 109.077 .9.962 21.831 6 12.045 127.130 10.190 25.445 7 21.465 - 18.159 - 8 0.995 - 6.722 - 9 1.470 - 6.207 - -p- 10 1.786 - 7.542 - TOTALS 219.290 886.206 1W TABLE 34. Numbers caught and catch-per-unit-effort (CPUE*) by sampling period, total catch, and total CPUE for young-of-the-year Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone americana for haul seine and otter trawl during the 1980 Juvenile Recruitment Survey. SPECIES GEAR SAMPLING PERIOD TOTAL I III IV V VI VII VIII Ix x A. Total Catch By Gear Type Alosa hs 21 9 5 1 3 6 36 25 2 0 108 aestivalis ot 24 1 0 2 0 0 0 0 0 0 27 Alosa hs 2 10 39 38 44 36 18 7 0 0 194 pseudoharengus ot 1 1 2 7 11 12 2 2 0 0 38 Morone hs 0 4 5 4 11 10 17 3 1 1 55 saxatilis ot 0 4 0 0 1 1 0 1 1 0 8 Morone hs 1 33 49 130 146 463 171 215 .65 42 1,315 americana ot 2 2 372 120 237 121 277 225 98 0 1,453 B. CPUE* By Gear Type Alosa hs 1.05 0.64 0.25 0.05 0.15 0.30 2.00 1.38 0.11 0.0 aestivalis ot 2.00 0.09 0.0 0.22 0.0 0.0 0.0 0.0 0.0 0.0 Alosa hs 0.10 0.71 1.95 1.90 2.20 1.80 1.00 0.38 0.0 0.0 pseudoharengus ot 0.08 0.09 0.18 0.77 0.91 1.00 0.18 0.18 0.0 0.0 Morone hs 0.0 0.29 0.25 0.20 0.55 0.56 0.94 0.17 0.06 0.0 saxatilis ot 0.0 0.36 0.0 0.0 0.08 0.08 0.0 0.09 0.08 0.0 Morone hs 0.05 2.35 2.45 6.50 7.30 23.15 9.50 11.94 3.61 3.00 americana ot 0.16 0.18 33.81 13.33 19.75 10.08 25.18 20.45 8.16 0.0 *CPUE: total number of a species/total number of hauls or runs TABLE 35. Numbers caught and catch-per-unit-effort (CPUF*) by sampling station, total catch, and total CPUE for young-of-the-year Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone americana by haul seine and otter trawl during the 1980 Juveni Recruitment Survey.' SPECIES GEAR SAMPLING STATION TOTAL 1 2 3 4 5 6 7 8 9 10 A. Total Catch By Gear Type Alosa hs 50 23 18 8 9 0 0 0 0 0 108 aestivalis ot 6 20 1 0 0 0 0 0 0 0 27 Alosa hs 34 2 30 128 0 0 0 0 0 0 194 pseudoharengus ot 12 5 0 2 9 10 0 0 0 0 38 Morone hs 15 6 6 12 1 4 11 0 0 0 55 9-axatilis ot 0 1 0 1 2 4 0 0 0 0 8 Morone hs 127 441 172 312 121 142 0 0 0 0 1,315 americana ot 339 505 402 20 73 115 0 0 0 0 1,453 B. CPUE* By Gear Type Alosa hs 2.50 1.15 0.90 0.40 0.45 0.0 0.0 0.0 0.0 0.0 aestivalis ot 0.35 1.11 0.05 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Alosa hs 1.70 0.10 1.50 6.40 0.0 0.0 0.0 0.0 0.0 0.0 pseudoharengus ot 0.70 0.27 0.0 0.15 0.50 0.55 0.0 0.0 0.0 0.0 Morone hs 0.75 0.30 0.30 0.60 0.05 0.20 1.10 0.0 0.0 0.0 saxatilis ot 0.0 0.60 0.0 0.08 0.11 .022 0.0 0.0 0.0 0.0 Morone, hs 6.35 22.05 8.60 15.60 6.05 7.10 0.0 0.0 0.0 0.0 americana ot 19.94 28.05 23.64 1.53 4.05 6.38 0.0 0.0 0.0 0.0 CPUE: total number of a species/total number of hauls or runs do & A m6- 667 m6', J&,- iih tj- A TABLE 36. Standing crop as numbers per hectare for young-of-the-year Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone american@@ -colle-cted by haul seine and otter trawl in each sampling j;e-riod during tHe 1980 Juvenile Recruitment Survey SPECIES GEAR SAMPLING PERIOD I ii III IV V" VI VII VIII Ix x Alosa hs 23.0 11.0 5.0 1.0 3.0 7.0 41.0 28.0 2.0 0.0 aestivalis ot 8.0 0.4 0.0 0.9 0.0 0.0 0.0 0.0 0.0 0.0 Alosa hs 2.0 12.0 43.0 41.0 48.0 39.0 6.0 9.0 0.0 0.0 pseudoharengus ot 0.3 0.4 0.7- 3.0 3.0 4.0 0.7 0.7 0.0 0.0 Morone hs 0.0 5.0 5.0 4.0 12.0 11.0 19.0 3.0 0.0 0.0 saxatilis ot 0.0 1.0 0.0 0.0 0.3 0.3 0.0 0.3 0.3 0.0 Morone hs 1.0 40.0 53.0 141.0 159.0 505.0 192.0 248.0 73.0 47.0 americana ot 0.6 0.7162.0 52.0 75.0 38.0 97.0 78.0 31.0 0.0 TABLE 37. Standing crop as numbers per hectare for young-of-the-year Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone americana collected by P@-a-u-l seine and otter trawl at each sampling H-a-tion during the 1980 Juvenile Recruitment Survey. SPECIES GEAR SAMPLING STATION 1 2 3 4 5 6 7 8 9 10 Alosa hs 42 19 15 7 8 0 0 0 0 0 aestivalis ot 2 5 0.2 0 0 0 0 0 0 0 Alosa hs 29 2 25 108 0 0 0 0 0 0 pseudoharengus ot 3 1 0 1 2 2 0 0 0 0 Morone hs 13 5 5 10 0.8 3. 9 0 0 0 saxatilis ot 0 0.2 0 0.3 0.4 0.8 .0 0 0 0 Morone hs 107 373 146 364 102 120 0 0 0 0 americana ot 90 120 86 5 15 23 Recordedin whole numbers except when value less than one un EW NA, �"@- min, 96 TABLE 38 Reported commercial catch as pounds caught of American shad and alewife/blueback herring combined from the Susquehanna River, Susquehanna Flats, and the Northeast River* from 1968 through 1980. YEAR Shad REPORTED CATCH Herring" 1968 175,878 1,506,088 1969 200,321 937,612 1970 118,343 @635,347 1971 228,585 1,112,000 1972 188,278 251,066 1973 179,105 1,132,437 1974 50,389 783,810 1975 22,668 161,759 1976 10,223 63,498 1977 8,025 44,048 1978 2b,359 43,472 1979 2,321 34,647 1980 48 16,610 Sum of NOAA statistical subareas 090, 089, and 064, respectively Alosa aestivalis and Alosa pseudoharengus catch combined TABLE Species and number of individual finfish collected by haul seine during six sampling periods for the 1979 Juvenile Recruitment Survey. SPECIES SAMPLING PERIOOS TOTALS III IV V Vi VII VIII Ix X Alosa aestivalis 89 158 15 17 75 354 Alosa pseudoharengus 1 2 2 7 6 18 Alosa sapidissima 2 1 3 Anchoa mitchilli 1 4 1,129 32 Brevoortia tyrannus 394 1 96 772 39 1,302 Carpiodes cyprinus 1 1 Cyprinus carpio 10 11 6 7 4 2 40 Dorosoma cepedianum 5 3 570 1, 354 427 383 2,742 Etheostoma olmstedi 1 1 1 5 8 Esox lu-cius 1 1 Fundulus diaphanus 36 5 8 3 3 7 62 Fundulus heteroclitus 21 6 4 7 2 40 Hybognathus nuchalis 8 2 1 1 12 Hypentelium nigricans 10 10 Ictalurus punctatus 1 7 8 5 15 2 38 Leiostomus xanthurus 8 76 22 44 19 5 174 Lepomis auritus 2 1 1 1 5 Lepomis gibbosus 2 7 7 6 5 12 39 Lepomis macrochirus 1 4 7 9 4 25 Membras martinica 9 23 7 4 2 45 Menidia beryllina 193 85 71 99 107 144 699 Micropterus dolomieui 1 4 1 2 1 1 10 Micropterus salmoides 1 3 6 1 11 Morone americana 390 463 460 392 449 282 2,436 Morone saxatilis 17 23 18 17 22 7 105 Morone saxatilis X chrysops 1 1 Notropis hudsonius 51 185 283 435 382 316 1,652 Notropis spilopterus 33 74 37 13 2 1 160 Aw she- Nw, NA- aw 1 RE nwl`@ Epp. RM elm-, IM RIP- qw-F-:--- up:@ MR., M, MR_ Elm-, TABLE 3 9 , con SPECIES SAMPLING PERIODS TOTALS I II III IV V VI vii VIII Ix x Perca flavesceris 43 18 14 33 5' 27 140 Pomoxis annularis 1 1 Pomoxis nigromaculatus 1 1 2 Strongylura marina 1 1 1 3 Trinectes maculatus 1 1 2 TOTALS Species 22 24 24 24 27 21 33/ Numbers 1,295 1,179 1,649 2,464 3,444 1,276 11,307 co TABLE 40 Species and numbers of individual finfish collected by haul seine at ten sampling stations during the 1979 Juvenile Recruitment Survey. SPECIES SAMPLING-STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 62 75 126 22 5 11 51 354 Alosa pseudoharengus 4 11 2 1 is Alosa sapidissima 1 1 1 3 Anchoa mitchilli 3 1 34 1 229 575 323 1,166 Brevoortia tyrannus 2 668 620 12 1,302 Carpiodes cyprinus 1 1 Cyprinus carpio 1 5 12 13 3 1 2 1 2 40 Dorosoma cepedianum 527 1,360 .405 29 29 174 19 29 170 2,742 Etheostoma olmstedi 2 3 1 1 1 8 Esox lucius -1 1 Fundulus diaphanus 19 1 1 1 1 11 25 3 1 62 Fundulus heteroclitus 6 3 22 7 2 40 Hybognathus nuchalis 2 7 1 1 1 12 Hypentelium nigricans 10 10 Ictalurus punctatus 4 6 5 5 3 2 10 1 2 38 Leiostomus xanthurus 10 80 3 1 38 33 8 1 174 Lepomis auritus .1 4 5 Lepomis gibbosus 3 2 14 1 10 4 4 39 Lepomis macrochirus 4 20 1 25 Membras martinica 23 3 6 4 7 2 45 Menidia beryllina 135 29 16 27 182 239 56 6 9, 699 Micropterus dolomieui 1 1 3 2 3 10 Micropterus salmoides 1 10 11 Morone americana 456 537 142 329 341 583 2 2 3 41 2,436 Morone saxatilis 43 7 4 22 3 12 1. 2 105 Morone saxatilis X sl@sops 1 1 iTo-i-,@-O-pi-s hudsonius 1.6S 228 256 298 364 286 26 21 6 4 1,652 @@-qtroPis spilopterus 1 48 110 1 160 AN slw@ Iiif An I& I&-- min I& vfii@ ww@- shi-, a& I&- Win- Sim TABLE 40 con't. SPECIES SAMPLING STATIONS TOTAILS 1 2 3 4 5 6 7 8 9 10 Perca flavescens 2 20 18 19 9 39 33 140 Pomoxis annularis 1 Pomoxis nigromaculatus 2 Strongylura marina 1 1 3 Trinectes maculatus 1 1 2 TOTALS Species 20 17 18 17 18 18 20 13 14 16 33/ Numbers 1,464 3,031. 1,674 752 1,037 1,272 441 321 750 565 11,307 CD C) TABLE 41. Species and weights (grams) of finfish collected by haul seine during six sampling periods for the 1979 Juvenile Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS IV V VI VII VIII Ix X Alosa,aestivalis 89 260 29 19 129 526 Alosa pseudoharengus 8 8 16 39 52 123 Klosa sapidissima 8 2 10 Anchoa mitchilli 4 7 3,690 21 3,722 ffrevoortia tyrannus 2,812 1 1,585 13,480 608 18,486 Carpiodes cyprinus 1,500 1,500 Cyprinus carpio 16,042 13,530 12,150 lZ700 7,400 2,170 63,992 Dorosoma cepedianum 1,056 74 5,719 12,273 7,487 6,076 32,685 Etheostoma olmstedi 1 1 2 13 17 Ksox lucius 500. 500 Fundulus diaphanus 191, 20 26 12 10 24 283 Fundulus heteroclitus 115 23 15 27 8 188 ffybognathus nuchalis 70 38 18 13 139 Hypentelium nigricans 1,216 1,216 Tctalurus punctatus 76 289 1,921 324 945 3,561 teiostomus xanthuru-s 96 1,632 499 874 524 76 3,706 'Lepomis auritus 140 58 14 21 233 Lepomis gibbosus 62 189 128 195 140 374 1,088 Lepomis macrochirus 30 138 181 28 11 388 Rembras martinica 38 108 36 16 8 206 Menidia beryllina 371 254 85 165 153 262 1,290 1,Ticropterus dolomieui' 14 302 60 44 126 5 550 Micropterus salmoides 454 7 9 4 474 @4-orone americana 7,403 10,274 9,608 7,198 6,625 1,545 42,653 Morone saxatilis 81 269 148 101 108 74 781 Si -)-r-o-ne 'saxatilis X chrysops 35 35 n-)tropis hudsonius 338 1,294 1,971 2,650 1,993 1,608 8,854 t@lf)tropis spilqpterus 74 210 88 40 6 1 419 F- U W.: ERW RN Wt. Iff- Rw- RRR mpl,@--. ",q- W-.- TABLE con' t. SPECIES SAMPLING PERIODS TOTALS III IV V VI VII VIII Ix x Perca flavescens 1,274 345 364 749 127 280 3,139 Pomoxis annularis 6 6 Pomoxis nigromaculatus 2 30 32 Strongylura marina 50 34 44 128 Trinectes maculatus 12 2 14 TOTALS Species 22 24 24 24 27 21 33/ Numbers 30,633 29,485 36,681 38,728 43,177 13,240 191,944 TABLE 42 - Species and weights (grams) of finfish collected by haul seine at ten sampling stations during the 1979 Juvenile Recruitment Survey. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Alosa aestivalis 85 102 169 47 5 11 105 2 526 Alosa pseudoharengus 14 84 13 12 123 Alosa sapidissima 4 4 2 10 Anchoa mitchilli 6 4 23 2 600 2,037 1,050 3,722 frevoortia tyrannus 10 1Z715 4,903 858 18,486 Carpiodes cyprinus 1,500 1,500 Cyprinus carpio 1,000 4,237 13,420 33,223 3,800 1,362 1,500 3,200 2,250 63,992 Dorosoma Ee--p-eUlianum 3,031 12,575 5,676 510 1,98'0 5,993 218 .277 2,425 32,685 iHheostoma olmsteTT 3 10 1 1 2 13 Esox lucius 500 500 F-undulus diaphanus 72 5 4 .6 50 132 5 9 283 Fundulus heteroclitus 23 18 ill 28 8 188 Hybognathus nuchalis 38 56 14 18 13 139 Hypentelium nigricans 1,216 1,216 Ictalurus punctatus 226 1,062 335 1,132 202 11 523 26 44 3,561 Leiostomus xanthurus 278 1,620 74 20 913 693 96 12 3,706 fepomis auritus 58 175 233 Lepomis gibbosus 42 39 333 30 29 438 88 89 1,088 Eepomis macrochirus 161 156 71 388 Membras martinica 102 14 32 14 34 10 206 Renidia beryllina 135 39 24 49 447 529 40 6 21 1,290 Micropterus dolomieui 78 60 202 48 162 550 Hicropterus salmoides 454 20 474 Morone americana 9,374 5,545 4,632 7,307 6,005 8,048 113 198 106 1,325 42,653 Morone saxatilis 175 137 69 21 279 12 63 21 4 781 .H-orone -saxatilis X chrysops 35 35 Notropis hudsonius 514 1,648 1,309 2,445 1,740 1,928 49 160 37 24 9,854 !@otropis spilopterus 4 121 292 2 419 IL TABLE 42 con t. SPECIES SAMPLING STATIONS TOTALS 1 2 3 4 5 6 7 8 9 10 Perca flavescens 26 146 348 418 198 834 1,169 3,139 Pomoxis annularis 6 6 Pomoxis nigromaculatus 2 -30 32 Strongylura marina 44 50 34 128 Trinectes maculatus 12 2 14 TOTALS Species 20 17 18 17 18 18 .20 13 14 16 33/ Numbers 16,618 39,940 31,407 45,768 10,581 18,166 1-1,376 3,192 6,275 8,621 191,944 1.05 TABLE 43. Total catch and catch per haul by haul seine by sampling period for young-of-the-year Alosa sapidissima, Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, and Morone americana during the 1979 uve e Recruitment Survey. SPECIES SAMPLING PERIODS TOTALS 1 2 3 4 5 6 A. Total Catch Alosa sapidissima 0 2 0 1 0 0 3 Alosa, aestivalis 89 158 15 17 73 0 352 Alosa pseudoharengus 1 2 2 0 7 6 18 Morone saxatilis 14 20 12 14 1:8 4 82 Morone americana 0 35 76 145 165 222 643 B. Catch Per Haul Alosa sapidissima 0.0 0.10 0.0 0.05 0.0 0.0 0.03 Alosa aestivalis 5. 56 7.90 0.75 0.85 3.84 0.0 3.06 Alosa pseudoharengus 0.06 0.10 0.10 0.37 0.30 0.0 0.16 Morone sa'xatilis 0.88 1.00 0.60 0.70 0.95 0.20 0.71 Morone americana 0.0 1.75 3.80 7.25 8.68 11.10 5.40 Wo- qRna IW Rmj.- 1w RM RM RE,- mp--- I",-, TABLE 44. Total catch and catch per haul by haul seine by sampling station for young-of-the-year Alosa sapidissima, Alosa aestivalis, Alosa pseudoharengus, Morone saxatilis, @in-dmorone americana during the,1979 Juvenile Recruitment Survey. SPECIES SAMPLING STATIO NS TOTALS 1, 2 3 4 5 6 7 8 9 10 A. Total Catch Alosa sapidissima V 0 1 0 0 0 0 0 1 0 1 Alosa aestivalis 62-@ 75 126 22 5 11 51 0 0 0 352 Alosa pseudoharengus 0- 0 4 10 2 0 0 0 0 2 18 Morone saxatilis 40 5 3 3 16 3 10 0 2 0 82 Morone americana 42 256 43 63 113 124 1 0 1 0 643 B. Catch Per Haul Alosa sapidissima 0.0 0.0 0.08 0.08 0.0 0.0 0.0 0.00 0.08 0.0 Alosa aestivalis 5.17 6.25 10.50 1.83 0.42 1.00 4.25 0.0 0.0 0.0 Alosa pseudoharengus 0.0 0.33 0.83 0.17 0.0 0.0 0.0 0.0 0.0 Morone saxatilis 3.33 0.42 0.25 0.25 1.33 0.27 0.83 0.0 0.17 0.0 Morone americana 3.50 21.33 3.58 5.25 9.42 11.27 0.08 0.0 0.08 0.0 107 TABLE 45. Comparison of the population density (numbers per hectare) of young-of-the-year American shad,alewife herring, and blueback herring captured by haul seine and otter trawl from the Susquehanna drainage during 1968, 1969, and 1980. SPECIES SEASONAL AVERAGE (No./ha) 1969 1968-1969 1980 1980 Haul Seine Otter Trawl Haul Seine Otter Trawl American shad 103 4 0 0 Blueback herring 1,944 23 13 1 Alewife herring 86 66 23 1 108 FIGURE VII. Survey stations for the 1980 American Shad Juvenile Recruitment Survey. 9 10 1 8 SURVEY STATIONS 144 NUMBER NAME KEY 1 Wild Duck Cove Seine site 2 Seneca Point Trawl site 3 Cara Cove 4 Camp Rodney 5 Battery Island 6 Havre de Grace 7 Quarry 8 Spencer Island 9 Robert Island 7 10 Spangler's Rock Run PERRYVILLE 2 4:;@ CO A. HAVRE DE GRACE 3 F no 5 4 SANDY PT. 109 i FIGURE VIII-Numbers of yo,ung-of-the-year Alsoa aestivalis (0). and Alosa pseudoharengus caught by haul seine per sampling period during the 1980 Juvenile Recruitment Survey. 50 40 30- wd F 20 3 10 0 1 11 111 IN V VT V 1.1 V 11: 1IX x FIGURE IX., Numbers of young-of-the year Alosa aestivalis and Alosa pseudoharengus (Eo) c'aught by otter trawl per sampling period,during the 1980 Juvenile Recruitment Survey. 50 40 30 F@4 U U) z 20 z 10 0 III IV V VI VII VIII Ix x SAMPLING PERIODS wit FIGURE Numbers of young-of-the-year Alosa aestivalis (D and Alosa pseudoharengus (0 ) caught by haul seine ML per sampling station cluring the 1980 Juvenile Recruitment Survey. '128 60- -50- E-4 40- wo U) 30- @D z 20- 10- 0 1 2 3 4 5 6 7 8 9 10 SAMPLING STATIONS 112 FIGURE X-T. Numbers of young-of-the-year Alosa aestivalis (EI) and Alosa pseudoharengus (EI) caught by otter trawl per sampling stations during the 1980 Juvenile Recruitment Survey. 60 50 40 U) 14 rQ X 30 z 20 10 NN 0 1 2 3 6 7 8 9 10 SAMPLING STATIONS 113 JOB V. LITERATURE REVIEW AND SURVEY A. Extensive literature concerning the biology and management of American shad exists primarily due to the species' sport and commercial value and its widespread range along the entire Atlantic coast. Mansueti and Kolb (1954) cited 1,314 literature sources in their publication "A Historical Review of the Shad Fishery of North America" while Dr. Timothy Robbin3 (pers. comm.) estimates that approximately 800 literature sources have been produced on the American shad since 1954. In order to upgrade Project staff familiarity with both .published and unpublished material, a literature search was undertaken by the Maryland Tidewater Administration. Accumulation and analysis of pertinent literature and subsequent comparison with Maryland's situation is a prime requisite for improvement of the state's ability to rationally manage its shad stocks. B. Queried information sources during the past 12 months include 1. Journals/Periodicals- Transactions of the American Fisheries Society Canadian Journal of Fisheries and Aquatic Sciences Ecology Estuaries Progressive Fish Culturist Scientific American Biological.Conservation Fisheries Limnology and oceanography Natural History American Midland Naturalist Marine Fisheries Review Fishery Bulletin, National Marine Fisheries Service Fishery Bulletin, Fish and Wildlife Service 114 Research Reports, Fish and wildlife Service r-J National Marine Fisheries Service Commercial Landings Fish and Wildlife Service Computer Reference System 2. State Governmental Agencies- Florida Department of Natural Resources, Division of Marine Resources Georgia Department of Na tural Resources, Coastal Resources Division South Carolina Wildlife and Marine Resources Department, Mc-rine Resources Division North Carolina Department of Natural Resources and Community Development, Division of Marine Resources Virginia Marine Resources Commission Maryland Department of Natural Resources, Tidewater Administration :.4 Delaware Department of Natural Resources and Environmental Control, Division of Fish and Wildlife New Jersey Department of Environmental Protection, Division of Fish, Game and Shellfish New York Department of Environmental Conservation, Division of Fish and Wildlife Connecticut Department of Environmental Protection, F Marine Region 3. Federal Government Agencies- F Department of Interior, Fish and Wildlife Service Department of Commerce, National Marine Fisheries Service 4. Private Consultants Radiation Management Corporation F Environmental Resources Management, Inc. Martin Marietta Corporation -7 National Environmental Services, Inc. Lawler, Matusky, and Skelly 5. Academic Institutions F University of Maryland, Sea Grant Johns Hopkins University, Applied Physics Laboratory University of Maryland, Center for Environmental and Estuarine Studies College of William and Mary, Virginia Institute of Marine Science (VIMS) V 115 6. Personal Communication A great deal of information was obtained through personal contact with various individuals and groups. Discussions with the Maryland Watermens Association and their various county chapters, individual commercial fishermen, and seafood processors provided insight into the Maryland shad fishery and market system. Further direct contact with specific w,-.termen was invaluable to the Project's field operations as well as providing useful supplemental data such as catch-per-unit of effort. Personal communication with various state conservation agencies was helpful to all aspects of Maryland's program. The Connecticut DEP assisted in the difficult job of ageing American shad scales. New Jersey DEP personnel provided information concerning the resurgence of Delaware River shad runs. This information may well be applicable to Maryland's problem. Agreement was reached.with the VI14S to tag adult American shad in the Virginia portion of the Chesapeake Bay during 1981 so that their movements into Virginia tributaries and the Maryland Bay would become better understood. C. To better understand the value of this literature survey to Maryland's American shad investigation, a brief discussion concerning one aspect of the survey is presented below. Table 46 presents the reported commercial catch.of American shad by state or major tributary along the east coast from 1962 to 19-80. Analysis and comparison of any commercial catch data can be tenuous at times due to differences in effort, gear types employed, gear selectivity, and the accuracy of the.reported totals. Because these conditions 116 which influence this data were unknown, specific conclusions could not be drawn from simple comparisons. However, certain trends appeared obvious with respect to Maryland and warranted mention. All east coast states have experienced both increases and decreases in reported American shad landings from 1962 to 1980. The most dramatic declines appear to be from the Chesapeake Bay south. With the exception of South Carolina, these southern states have experienced declines from their average catch ranging from 434,000 pounds in Georgia to 1,557,100 pounds in Maryland during this 19 year period. Catches from the three northern rivers and South Carolina, however, appear to be stable and increasing. The declining shad catch from the Delaware River during the late 1960's through the mid-.1970's can be attributed to the pollution block created by the cities of Philadelphia and Trenton (Chittenden 1975, Lupine pers. comm.) Poor water qual ity greatly restricted upstream migration of spawning adults in the spring and downrunning juveniles in the fall. Extensive pollution control measures in these problem areas have shortened the duration of this block, thus permitting more nearly unaltered movements of both adults and young-of-the-year. Consequently, Delaware River American shad catches by both commercial watermen and sport anglers have experienced a sharp increase during the past five years. The 1980 Hudson River totals were expected to substantially exceed the,record 1979 totals (Blossum pers. comm.) In each of these three northern rivers and South Carolina a continuous research program has resul.ted in effective regulations cl@ and management policies for their shad fishery (Fredin 1954, Talbot 1954, Walburg 1963, White and Vurtis 1969, Curtis 1974, Leggett 1976, Marcy 1976, Chittenden 1974, Crochet et al-1976, Crecco 1979, Lupine 1980, Minta et al.1980). This has 117 been one of the major factors contributing to stabilized runs and commercial catches in these locations. Specifically, American shad in the Connecticut River have been extensively studied and managed for over 20 years, and the corresponding commercial harvest has been the most stable of any major east coast river. The ability to return Maryland's American shad population to stable harvestable levels is directly related to the state's continued study and monitoring of both the fish and its various limiting fa.ctor s (pollution, stream blockage, habitat alteration, overfishing). Synthesis of this information along with thatobtained from outside sources into an effective management policy, strengthened by enforceable regulations should logically follow. 1W WE 0, R-1. IFE OR RK qP W. IPP WP qN, IPL RM, RP--. Ok OPP No IM ME TABLE 46. Reported commercial catch of American shad from all waters in Florida, Georgia, South Carolina, North Carolina, Virginia, Maryland, and the Delaware, Hudson, and Connecticut Rivers from 1962 through 1980. CATCH (lbs.) SOUTH NORTH DELAWARE HUDSON CONNECTICUT YEAR FLORIDA GEORGIA CAROLINA CAROLINA RIVER RIVER RIVER 1962 760,000 527,000 115,000 764,000 183,000 218,149 499,369 1963 590,000 331,000 120,000 693,000 196,000 132,564 329,077 1964 613,000 314,000 120,000 640,000 332,000 78,084 311,460 1965 75F,000 376,000 176,000 1,069,000 333,000 119,958 347,835 1966 530,000 386,000 119,000 701,000 221,000 67,908 277,779 1967 319,000 334,000 132,000 777,000 136,000 76,491 278,903 1968 531,000 569,000 110,000 842,000 60,300 113,100 251,699 1969 390,000 618,000 176,000 718,645 23,400 122,676 205 ' 061 1970 218,000 532,000 148,000 953,000 29,400 95,900 199,754 1971 253,000 420,000 99,000 680,212 16,000 70,038 2001941 1972 120,000 344,000 159,000 468,484 35,400 93,660 201,748 1973 99,000 239,000 26,000 321,000 29,300 153,357 249,940 1974 100,000 162,000 24,000 369,000 27,544 163,690 230,349 1975 33,000 182,000 62,000 241,000 54,498 196,000 271,957 1976 28,000 93,000 32,000 167,000 75,808 183,200 374,125 1977 97,000 118,000 80,000 120,201 116,363 120,300 308,217 1978 130,000 172,000 287,000 402,017 141,726 306,500 283,662 1979 95,000 250,000 197,000. 277,818 119,291 430,300 204,879 1980 141,000 172,000 270,000 194,333 93,700* 1,296,970 323,662 reported commercial landings of Delaware state fishermen only co 119 TABLE 46. continued CATCH (LBS.) YEAR MARYLAND VIRGINIA 1962 1,574,681 2,201,200 1963 826,227 2,309,100 1964 888,923 2,940,875 1965 1,309,577 .2,940,875 1966 1,126,996 2,413,356 1967 886,647 2,101,953 1968 911,346 2,579,249 1969 1,095,332 2,117,002 1970 1,037,731 4,095,923 1971 946,426 1,507,163 1972 821,260 2,049,358 1973 597,793 2,419,810 1974 220,482 1,521,318 1975 183,757 1,095,103 1976 109,173 693,935 1977 73;015 1,409,800 1978* 79,439 1,221,880 1979* 33,668 919,560 19 8 0 22,704 874,807 Atlantic Ocean landings not included 1210 CONCLUSIONS AND RECOMMENDATIONS The major conclusion derived from the 1980 data is that American shad stocks in the upper Chesapeake Bay are in a precarious condition. Prior to 1972, it was common for commercial fishermen to catch as many shad in a week as the estimated upper Bay population for 1980. Sport angling success during the 1960's and early 1970's was among the best along the east coast. Though never as plentiful as other species, young-of-the-year American shad were regularly collected in various head-of-the-Bay juvenile surveys through 1972. Closing Maryland's waters to all American shad fishing in 1980 was a serious but necessary step to protect the remaining brood stocks. Mansueti and Kolb (1953) noted that the evidence from the majority of previous investigations clearly indicated that overfishing was the primary cause of reduced and declining shad runs in Maryland. Overfishing was also identified as a major factor in declining shad runs on the Hudson River (Talbot 1954), the Connecticut River (Fredin 1954, Marcy 1976, Leggett 1976, Crecco 1979), and in South Carolina (Crochet et al. 1976). Other factors have been cited as major reasons for Maryland's shad decline. Sidell (1979) stated that barriers preventing anadromous species from reaching their spawning grounds has been the primary cause of fishery declines in the Susquehanna River. Beginning in 1830, construction of dams precluded American shad from ascending the river to their uppermost spawning area, Binghamton, New York, river mile 318. With completion of Conowingo Dam in 1928 all migratory fish were restricted to only the lower 10 miles of the Susquehanna River. The effects of pollution and habitat alteration pose serious threats to spawning adults, eggs, and larvae. These conditions probably operate to make reproduction less successful for already depleted brood stocks. However, insufficient data indicating changes in pollution levels and habitat alterations for specific 121 spawning and nursery areas over time makes quantitative relationships difficult, if not impossible, to ascertain. On the basis' of the information presented in this report, the following management recommendations are presented. I. Continuation of Closed Fishing Season The scarcity of both spawni .ng adults and juvenile American shad precludes any recreational or economic incentive to reopen the fishery. Continuation of the fishing ban through 1984 would maximize protection of the remaining brood stocks and allow their quickest rebuilding. As mentioned in Job IV., several authors have noted a relationship between the numbers of juvenile American shad and the numbers of spawning adults three to five years later (Chittenden 1975, Marcy 1976, Minta et. al. 1980). Because recruits would not return to Maryland waters for three to five years after being spawned a minimum closure of five years is required to permit the return of'at least one unfished generation. A five year closure would also eliminate the problem of immediate "fishing up" whereby individuals who would not normally enter the fishery do so because of nominal increased catches by regular fishermen, thereby overfishing the stocks before they have a chance to rebuild to safe harvestable levels. If the number of spawners in one generation is overfished, thus reducing juvenile recruitment, numbers of fish returning three to five No years later as adults will be decreased. This condition is further compounded if this returning cohort is itself overfished. One successful year class will not'restore Maryland shad runs to harvestable levels. II. Chemical Monitoring @J Overfishing is probably not the only adverse condition limiting Susquehanna brood stocks and successful recruitment. The effect of pollution on both adults and juveniles (see Job IV) needs to be investigated. Analysis of water samples collected at various locations throughout the Susquehanna drainage would be beneficial in determining the types of pollutants presen@,, J 12`2 concentrations, and in certain instances their origin. In addition, chemical analysis of both tissues and gonads from Susquehanna shad is needed to determine if contaminants accumulated in the adults are limiting successful reproduction. Adult contamination may result in production of non-fertile eggs .and larvae and in hatching deformed, diseased, or weakened larvae incapable of survival. A simple and inexpensive method to-test the viability of upper Bay American shad eggs and milt would be to place fe)-tilized eggs in shad hatching boxes stationed throughout the area and monitor their hatching and development. III. Project Continuation and Expansion Few specific trends and conclusions can be drawn from one year's data. Successful management practices such as those for the Connecticut River involve the accumulation and analysis of data gathered over many years. Since this data is non-existent for any Maryland shad stocks, continuation of the present investigation is of paramount importance. Effective management policies are only possible with a comprehensive data base. Data expansion during 1981 centers on a proposed tagging experiment of American shad in the Virginia portion of Chesapeake Bay. The effects of Virginia's fishery on Maryland shad stocks is unknown. This exercise will provide preliminary information concerning effort, the relative importance of 'the Potomac River as a spawning area, and the possible exploitation rates attributable to the by-catch provisions of the 1981 Maryland.closure. As Walburg and Nichols (1967) state, "Successful management probably requires consideration of Chesapeake Bay stocks as units without regard to political boundaries." IV. Supplemental Stocking Supplemental stocking of both adults captured from other areas and hatchery reared eggs and larvae is not recommended at this time for the lower (=Maryland) Susquehanna drainage. From 1875 to 1950 over 199,000,000 shad fry were reared 123 and placed into nine different Maryland rivers; Potomac, Patuxentl Bush, Susquehanna, Northeast, Sassafras, Chester, Choptank, and Wicomico. These releases, however, were not successful in stopping the Maryland shad catches declining from over seven million pounds in 1890 to 1.4 million pounds in 1950. Talbot (1954) concluded that no correlation ex isted between hatchery operations and the estimated population of American shad entering the Hudson River from 1915 to 1950. The recent resu rgence of Delaware Ri-er shad runs has been erroneously concluded by the public to be the result of stocking adults collected from various east coast rivers, particularly the Susquehanna. Chittenden (1975) stated that the dominant factor affecting the abundance of American shad runs on the Delaware River for the past 60 years was the pollution block centered around the Philadelphia area. Delaware River fishery research personnel (Lupine pers. comm.) state that the increase in both sport and commercial landings during the late 1970's is a result of a decline in both the severity and duration of this pollution block. They concluded that artificial stocking of adults into the Delaware, terminated in the late 1960's, had little if any beneficial effect on the river's native brood stock. Until the conditions causing reproductive failure at the head of Chesapeake Bay can be defined, and corrective measures implemented, the stocking of hatchery produced eggs and larvae and transplanted adults will not solve the problem. It is unrealistic to assume that the deleterious factors presently affecting natural populations and reproduction will not produce similar results on artificially propagated and transplanted organisms. 124 LITERATURE CITED Bailey, N. J. J. 1951- On estimating the size of mobile populations from recapture data. Biometrika 38:293-306. Boone, J. and J. Uphoff. 1980. Estuarine fish recruitment survey July 1, 1979 - June 30, 1980. Federal Aid Project F-27-R-6 Performance Report. unpubl. 107 p. Carter, W. R., 111. 1973. Ecological study of the Susquehanna River and its tributaries below Conowingo Dam. Federal Aid Project AFSC-1 Completion Report U. S. Dept. Commerce, NOAA, NMFS. 122 p. Cating, J. P. 1953. Determing age of Atlantic shad from their-scales. U. S. Fish Wild. Serv., Fish Bull. 54(85):187-199. Chapman, D. G. 1951. Some properties of the hyergeometric distribution with application to zoological sample census. Univ. Calif. Publ. Stat. 1:131-160. Chittenden, M. E., Jr. 1969. Life history and ecology of the American shad, Alosa sapidissima, in the Delaware River. Ph. D. Thesis, Rutgers Univ., New Brunswick, N.J., 458 p. 1975. Dynamics of American shad, Alosa sapidissima, runs in the Delaware River. Fish. Bull. 73(3):487-494. Colston, N. V. 1974. Characterization and treatment of urban land runoff. EPA:' Environmental Protection Series: EPA 670/2-74-096. Crecco, V. A. 1979. Population dynamics of the American shad, Alosa sapidissima, in the Connecticut River, 1940- 1977. ---STEa-te logical and Natural History Survey of Connecticut Department of Environemntal Protection. 216 p. Crochet, D. W., D. E. Allen, and M. L. Hornberger. 1976. Commercial anadromous fishery Waccamaw and Pee Dee Rivers. Federal Aid Project AFC-5 Completion Report. South Carolina Wild. Mar. Res. Dept. 114 p. Curtis, T. A. 1974. Anadromous fish survey of the Santee and Cooper River system. South Carolina Wild. Mar. Res. Dept. Annual Progress Report, Proj. AFS-3-3, July 1, 1973-June 30, 1973. 44 p. Fredin, R. A. 1954. Causes of fluctations in abundance of Connecticut River Shad. U. S. Fish Wildl. Serv., Fish. Bull. 54:247-259. 125 Friedersdorff, J. W. and C. F. Barren. 1978. Delaware River Basin Anadromous Fishery Project Special Report No. 4, The 1977 Delaware River Adult American shad Population estimate. 16 p. Foerster, J. W. and S. P. Reagan. 1977. Management of the Chesapeake Bay American shad fishery. Biol. Conserv. 12:179-201. Johnson, H. B., D. W. Crocker, B. F. Holland, J. W. Gilliken, D. L. Taylor,*M. W. Street, J. G. Loesch, W. H. Kriete, and J. G. Travelstead. 1978. Biology and management of mid-Atlantic anadromous fishes under extended jurisdiction. Ann. Rep., AFCS 9-2. 175.p. Jones, R. A., P. Minta, and V. A. Crecco. 1976 A review of- American shad studies in the Connecticut River. Proceedings Am. Shad Workshop, NMFS, Amhurst, Mass. 350 p- Judy, M. H. 1961. Validity of age determination from scales of marked American shad. U. S. Fish Wildl. Serv. , Fish. Bull. 61:161-170. Kriete, W. H., Jr and J. G. Loesch. 1980. Design and relative efficiency of a bow-mounted pushnet for sampling pelagic fishes.. Trans. Am. Fish. Soc. 109:649-652. La Pointe, D. F. 1958. Age and growth of the American.shad... from three east coast Rivers. Trans. Am. Fish. Soc. 87-:139-150. Leggett, W. C. 1969. Studies on the reproductive biology of the American shad,'Alosa sapidissima, A comparison of populations from four,rivers in the Atlantic.seaboard. Ph. D. Thesis. McGill Univ. 125 p. 1976. The American shad, Alosa sapidissima, w4th special re.-Eerence to its migrations and population dynamics in the Connecticut River. In D'. Merriman and L. M. Thorpe (eds.). The Connecticut River ecological study: The impact of a nuclear power plant. Am. Fish. Soc. Monogr. 1. 252 p. and J. E. Carscadden. 1978. Latitudinal variations in reproductive characteristics of American shad (Alosa sapidissima): evidence for population specific strategies in fish. J. Fish. Res. Board Can. 35:1469-1478. Lofton, A. J. 1979. Delaware River Basin Anadromous Fishery Project Completion Report. 1978 American Shad Population Report. 18 p. 126 Lupine, A. J. 1980. Delaware River American shad population estimate. Del. River Fish. Proj. F-38-R Spec. Rep. #1 13 p. Mansuetti, R. 1958.' A brief review of fish and fishes of the lower Susquehanna region in Maryland and Pennsylvania. Md. Dept. Res. Ed. Ref. 14 p. and H. Kolb. 1953. A historical review of the shad fisheries of North America. Md. Dept. Res. Ed., Ches. Biol. Lab. Publ. 97. 293 p. Marcy. B..C., Jr. 1976. Early life history studies of American shad in the lower Connecticut River and the effects of the Connecticut Yankee plant. In D. Merriman and L. M. Thorpe (eds.). The Connecticut River ecological study: The impact of a nuclear power plant. Am. Fish. Soc. Monogr. 1. 252 p. Middaugh, D. P., J. A. Couch, and A. M. Grove. 1977. Responses of early life history stages of striped bass, Morone saxatilis, to chlorination. Ches. Sci. 18:141-153. Minta. P. 1980. Connecticut River shad study. Sixth annual report submitted to Northeast Utilities Company. Conn. Dept. Envir. Prot. 19 P. V. A Crecco, and R. P. Jacobs. 1980. Connecticut Rive-r shad studies, 1977-1979. Fed. Aid Proj. AFC-11 Final Report. unpubl. 23 p. Morgan, R. P., III, V. J. Rasin, and L. A. Noe. 1973. Effects of suspended sediments on the development of eggs and larvae of striped bass and white perch. Nat. Res. Inst. Univ. Md. Appendix XI NRI Ref. No. 73-110. 21 p. Pfeiffer, P. W. 1966. The results of a non-uniform probability creel census on a small state-owned lake. Proc. 20th Ann. Conf. Southeastern Assoc. Game Fish Comm. p 409-412. Radiation Management Corporation. 1979. Report on the sport fishing survey of the lower Susquehanna River below Conowingo Dam. RMC Ecological Division, Drumore, Pa. unpubl. 13 p. Radiation Management Corporation. 1979. Summary of the operation of the Conowingo Dam fish collection facility during the spring of 1979. Fish Facility Operation Rep. 8. 28 p. Ricker, W. E. 1975. Computation and interpretation of biological statistics-of fish populations. Bull. 191 Fish. Res. Brd. Canada. 382 p. 127! 7 Sidell, B. D. 1979. A review of the current status of the American shad (Alosa sapidissima) in the Susquehanna River. Ches. B@@y__Inst. Johns Hopkins Univ. Spec. Rept. (CB-70). 42 p. St. Pierre, R. 1978. Historical review of the American shad and river herring fishery of the Susquehanna River. U. S. Dept. Int. Fish Wild. Serv. unpub. 40 p. Sykes, J. E. and B. A. Lehman. 1957. Past and present Delaware River shad fishery and considerations for "Its future. U. S. Fish Wildl. Serv., Res.. Rep. 46. 25 p. Talbot, G. E. 1954. Factors associated with fluctuations in -bundance of Hudson River shad. Fish. Bull. U. S. 56:373-413. ij Li Ulrich, G., N. Chipley, J. W. McCord, and D. Cupka. 1979. Development of fishery management plans for selected anadromous fishes in South Carolina and Georgia. South Carolina Wildl. Mar. Res. Spec. Sci. Rep. #14. 135 p. Walburg, C. H. 1963. Parent-progeny relation and estimates of optimum yield for American shad in the Connecticut River. Trans. Am. Fish. Soc. 92:436-439. and P. R. Nichols. 1967. Biology and management of the American shad and status of the fisheries, Atlantic Coast of the United States, 1960. U. S. Fish Wildl. Serv. Spec. Sci. Rep. Fish. 550. 105 p. White, M. G., III, and T. A. Curtis. 1969. Anadromous fish survey of the Black River and Pee Dee River watersheds. South Carolina Wildl. Mar. Res. Dept. Job Progress Rep. Proj. AFS 2-4, July 1, 1968 June 30, 1969. 73 p. Whitney, R. R. 1961. The Susquehanna fishery study, 1957- 1960. A report of a study on the desirability and feasability of p*assing fish at Conowingo Dam. Md. Dept. Res. Educ. Contract No. 169. 81 P. I I I I I rl I I I I I I I I I I iiiiin@ililimiiiliii 1 3 6668 00000 9201 I - - I