[Federal Register Volume 80, Number 19 (Thursday, January 29, 2015)]
[Notices]
[Pages 4886-4906]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-01692]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XD512
Takes of Marine Mammals Incidental to Specified Activities; Low-
Energy Marine Geophysical Survey in the Ross Sea, January to February
2015
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an Incidental Harassment Authorization
(IHA).
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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA),
notification is hereby given that NMFS has issued an IHA to the
National Science Foundation (NSF) Division of Polar Programs, and
Antarctic Support Contract (ASC) on behalf of Louisiana State
University, to take marine mammals, by Level B
[[Page 4887]]
harassment, incidental to conducting a low-energy marine geophysical
(seismic) survey in the Ross Sea, January to February 2015.
DATES: Effective January 24 to April 9, 2015.
ADDRESSES: A copy of the IHA and the application are available by
writing Jolie Harrison, Chief, Permits and Conservation Division,
Office of Protected Resources, National Marine Fisheries Service, 1315
East-West Highway, Silver Spring, MD 20910 or by telephone to the
contacts listed below (see FOR FURTHER INFORMATION CONTACT).
An electronic copy of the IHA application containing a list of the
references used in this document may be obtained by writing to the
address specified above, telephoning the contact listed here (see FOR
FURTHER INFORMATION CONTACT) or visiting the Internet at: http://www.nmfs.noaa.gov/pr/permits/incidental/. Documents cited in this
notice, including the IHA application, may also be viewed by
appointment, during regular business hours, at the aforementioned
address.
NSF and ASC prepared an ``Initial Environmental Evaluation/
Environmental Assessment to Perform Marine Geophysical Survey, Collect
Bathymetric Measurements, and Conduct Coring by the RVIB Nathaniel B.
Palmer in the Ross Sea'' (IEE/EA) in accordance with the National
Environmental Policy Act (NEPA) and the regulations published by the
Council of Environmental Quality (CEQ). It is posted at the foregoing
site. NMFS has independently evaluated the IEE/EA and has prepared a
separate NEPA analysis titled ``Environmental Assessment on the
Issuance of an Incidental Harassment Authorization to the National
Science Foundation and Antarctic Support Contract to Take Marine
Mammals by Harassment Incidental to a Low-Energy Marine Geophysical
Survey in the Ross Sea, January to April 2015.'' NMFS also issued a
Biological Opinion under section 7 of the Endangered Species Act (ESA)
to evaluate the effects of the low-energy seismic survey and IHA on
marine species listed as threatened or endangered. The NMFS Biological
Opinion is available online at: http://www.nmfs.noaa.gov/pr/consultations/opinion.htm.
FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Jolie Harrison,
Office of Protected Resources, NMFS, 301-427-8401.
SUPPLEMENTARY INFORMATION:
Background
Sections 101(a)(5)(A) and (D) of the MMPA, (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce (Secretary) to allow, upon request,
the incidental, but not intentional, taking of small numbers of marine
mammals by United States citizens who engage in a specified activity
(other than commercial fishing) within a specified geographical region
if certain findings are made and either regulations are issued or, if
the taking is limited to harassment, a notice of a proposed
authorization is provided to the public for review.
An authorization for incidental takings shall be granted if NMFS
finds that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking and requirements
pertaining to the mitigation, monitoring and reporting of such takings
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103
as ``. . . an impact resulting from the specified activity that cannot
be reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival.''
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as: Any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild [Level A harassment]; or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering [Level B harassment].
Summary of Request
On July 15, 2014, NMFS received an application from NSF and ASC
requesting that NMFS issue an IHA for the take, by Level B harassment
only, of small numbers of marine mammals incidental to conducting a
low-energy marine seismic survey in International Waters (i.e., high
seas) in the Ross Sea during January to February 2015. The IHA
application includes an addendum which includes incidental take
requests for marine mammals related to icebreaking activities.
The research will be conducted by one research institution, the
Louisiana State University (Baton Rouge). NSF and ASC plan to use one
source vessel, the RVIB Nathaniel B. Palmer (Palmer), and a seismic
airgun array and hydrophone streamer to collect seismic data in the
Ross Sea. The vessel will be operated by ASC, which operates the United
States Antarctic Program (USAP) under contract with NSF. In support of
the USAP, NSF and ASC plan to use conventional low-energy, seismic
methodology to perform marine-based studies in the Ross Sea, including
evaluation of the timing and duration of two grounding events (i.e.,
advances of grounded ice) to the outer and middle shelf of the Whales
Deep Basin, a West Antarctic Ice Sheet paleo ice stream trough in the
eastern Ross Sea (see Figures 1 and 2 of the IHA application). The
studies will involve a low-energy seismic survey, acquiring core
samples from the seafloor, and performing radiocarbon dating of benthic
foraminifera to meet a number of research goals. In addition to the
planned operations of the seismic airgun array and hydrophone
streamer(s), NSF and ASC intend to operate a single-beam echosounder,
multi-beam echosounder, acoustic Doppler current profiler (ADCP), and
sub-bottom profiler continuously throughout the survey. NMFS published
a notice making preliminary determinations and proposing to issue an
IHA on November 17, 2014 (79 FR 68512). The notice initiated a 30-day
public comment period.
Acoustic stimuli (i.e., increased underwater sound) generated
during the operation of the seismic airgun array and from icebreaking
activities may have the potential to cause behavioral disturbance for
marine mammals in the survey area. This is the principal means of
marine mammal taking associated with these activities, and NSF and ASC
have requested an authorization to take 18 species of marine mammals by
Level B harassment. Take is not expected to result from the use of the
single-beam echosounder, multi-beam echosounder, ADCP, and sub-bottom
profiler, as the brief exposure of marine mammals to one pulse, or
small numbers of signals, to be generated by these instruments in this
particular case as well as their characteristics (e.g., narrow-shaped,
downward-directed beam emitted from the bottom of the ship) is not
likely to result in the harassment of marine mammals. Also, NMFS does
not expect take to result from collision with the source vessel because
it is a single vessel moving at a relatively slow, constant cruise
speed of 5 knots ([kts]; 9.3 kilometers per hour [km/hr]; 5.8 miles per
hour [mph]) during seismic acquisition within the survey, for a
relatively short period of time
[[Page 4888]]
(approximately 27 operational days). It is likely that any marine
mammal will be able to avoid the vessel.
Description of the Specified Activity
Overview
NSF and ASC plan to use one source vessel, the Palmer, a two GI
airgun array and one hydrophone streamer to conduct the conventional
seismic survey as part of the NSF-funded research project ``Timing and
Duration of LGM and post-LGM Grounding Events in the Whales Deep Paleo
Ice Streams, Eastern Ross Sea Continental Shelf.'' In addition to the
airguns, NSF and ASC intend to conduct a bathymetric survey and core
sampling from the Palmer during the low-energy seismic survey.
Dates and Duration
The Palmer is expected to depart from McMurdo Station on
approximately January 24, 2015 and arrive at Hobart, Australia on
approximately March 20, 2015. Research operations will be conducted
over a span of 27 days (from approximately January 24 to February 26,
2015). At the end of the proposed research operations, the Palmer will
resume other operational activities, and transit to Hobart, Australia.
The total distance the Palmer will travel in the region to conduct the
research activities (i.e., seismic survey, bathymetric survey, transit
to coring locations and McMurdo Station) represents approximately
12,000 km (6,479.5 nmi). Some minor deviation from this schedule is
possible, depending on logistics and weather (e.g., the cruise may
depart earlier or be extended due to poor weather; or there could be
additional days of airgun operations if collected data are deemed to be
of substandard quality).
Specified Geographic Region
The planned project and survey sites are located in selected
regions of the Ross Sea (located north of the Ross Ice Shelf) and focus
on the Whales Deep Basin trough (encompassing the region between 76 to
78[deg] South, and between 165 to 170[deg] West) (see Figure 2 of the
IHA application). The low-energy seismic survey will be conducted in
International Waters. Figure 2 of the IHA application illustrates the
general bathymetry of the proposed study area near the Ross Ice Shelf
and the previously collected data with respect to seismic units and
dated cores. Water depths in the survey area are between 100 to 1,000
m. The low-energy seismic survey will be within an area of
approximately 3,882 km\2\ (1,131.8 nmi\2\). This estimate is based on
the maximum number of kilometers for the low-energy seismic survey
(1,750 km) multiplied by the area ensonified around the planned
tracklines (1.109 km x 2). The ensonified area is based on the
predicted rms radii (m) based on modeling and empirical measurements
(assuming 100% use of the two 105 in\3\ GI airguns in 100 to 1,000 m
water depths), which was calculated to be 1,109 m (3,638.5 ft) (see
Appendix B of the IHA application).
If icebreaking is required during the course of the research
activities in the Antarctica region, it is expected to occur on a
limited basis. The research activities and associated contingencies are
designed to avoid areas of heavy sea ice condition, and the Ross Sea
region is typically clear during the January to February time period
due to a large polynya which routinely forms in front of the Ross Ice
Shelf.
Researchers will work to minimize time spent breaking ice. The
planned science operations are more difficult to conduct in icy
conditions because the ice noise degrades the quality of the
geophysical and ADCP data. Also, time spent breaking ice takes away
from time supporting research. Logistically, if the vessel is in heavy
ice conditions, researchers will not tow the airgun array and streamer,
as this will likely damage equipment and generate noise interference.
It is possible that the low-energy seismic survey can be performed in
low ice conditions if the Palmer could generate an open path behind the
vessel.
Because the Palmer is not rated to routinely break multi-year ice,
operations will generally avoid transiting through older ice (i.e., 2
years or older, thicker than 1 m). If sea ice is encountered during the
cruise, it is anticipated the Palmer will proceed primarily through one
year sea ice, and possibly some new, very thin ice, and will follow
leads wherever possible. Satellite imagery from the Ross Sea region
(http://www.iup.physik.uni-bremen.de:8084/ssmis/) documents that sea
ice is at its minimum extent during the month of February.
Based on the proposed tracklines, estimated transit to the proposed
study area from McMurdo Station, and expected ice conditions (using
historical sea ice extent), it is estimated that the Palmer may need to
break ice along a distance of approximately 500 km (269.9 nmi) or less.
Based on the ship's speed of 5 knots under moderate ice conditions, 500
km represents approximately 54 hours of icebreaking operations. It is
noted that typical transit through areas of primarily open water
containing brash or pancake ice are not considered icebreaking for the
purposes of this assessment.
Detailed Description of the Specified Activity
NSF and ASC plan to conduct a low-energy seismic survey in the Ross
Sea from January to February 2015. In addition to the low-energy
seismic survey, scientific research activities will include conducting
a bathymetric profile survey of the seafloor using transducer-based
instruments such as a multi-beam echosounder and sub-bottom profiler;
acquiring bottom imaging, using underwater camera systems; and
collecting approximately 32 core samples from the seafloor using
various methods and equipment. Water depths in the survey area are 100
to 1,000 meters (m) (328.1 to 3,280.1 feet [ft]). The low-energy
seismic survey is scheduled to occur for a total of approximately 200
hours over the course of the entire cruise, which will be for
approximately 27 operational days in January to February 2015. The
planned research activities will bisect approximately 25,500 km\2\
(7,434.6 nmi\2\) in the Ross Sea region (see Figure 2 of the IHA
application). The low-energy seismic survey will be conducted during
the day (from nautical twilight-dawn to nautical twilight-dusk) and
night, and for up to 100 hours of continuous operations at a time. Note
that there will be 24-hour or near 24-hour daylight in the study area
between January 24 and February 26, 2015 (http://www.timeanddate.com/sun/antarctica/mcmurdo?month=2&year=2015). The operation hours and
survey length will include equipment testing, ramp-up, line changes,
and repeat coverage. Some minor deviation from these dates will be
possible, depending on logistics and weather. The Principal
Investigator is Dr. Philip Bart of the Louisiana State University
(Baton Rouge).
Grounding events in the Whales Deep Basin are represented by
seismically resolvable Grounding Zone Wedges. During the planned
activities in the Ross Sea, researchers will acquire additional seismic
data and multi-beam bathymetry and imaging to precisely define the
depositional and erosional limits of the outer and middle shelf
Grounding Zone Wedges. The collection of benthic samples and resulting
analyses will test the hypothesis and counter hypothesis regarding the
West Antarctic Ice Sheet retreat as it relates to the Whales Deep Basin
paleo ice stream through: (1) Radiocarbon dating in situ benthic
foraminifera isolated from diamict deposited on the
[[Page 4889]]
Grounding Zone Wedges foreset; (2) ramped pyrolysis of acid insoluble
organic isolated from diatom ooze overlying Grounding Zone Wedges
diamict; (3) calculating the duration of the two grounding events; and
(4) extracting pore-water from the Grounding Zone Wedges diamict to
determine salinity and [delta]\18\O values to test a numerical model
prediction regarding the West Antarctic Ice Sheet retreat.
The procedures to be used for the survey will be similar to those
used during previous low-energy seismic surveys by NSF and will use
conventional seismic methodology. The planned low-energy seismic survey
will involve one source vessel, the Palmer. NSF and ASC will deploy a
two Sercel Generator Injector (GI) airgun array (each with a discharge
volume of 105 in\3\ [1,720 cm\3\], in one string, with a total volume
of 210 in\3\ [3,441.3 cm\3\]) as an energy source, at a tow depth of up
to 3 to 4 m (9.8 to 13.1 ft) below the surface (more information on the
airguns can be found in Appendix B of the IHA application). A third
airgun will serve as a ``hot spare'' to be used as a back-up in the
event that one of the two operating airguns malfunctions. The airguns
in the array will be spaced approximately 3 m (9.8 ft) apart and 15 to
40 m (49.2 to 131.2 ft) astern of the vessel. The receiving system will
consist of one or two 100 m (328.1 ft) long, 24-channel, solid-state
hydrophone streamer(s) towed behind the vessel. Data acquisition is
planned along a series of predetermined lines, all of which will be in
water depths 100 to 1,000 m. As the GI airguns are towed along the
survey lines, the hydrophone streamer(s) will receive the returning
acoustic signals and transfer the data to the onboard processing
system. All planned seismic data acquisition activities will be
conducted by technicians provided by NSF and ASC, with onboard
assistance by the scientists who have planned the study. The vessel
will be self-contained, and the crew will live aboard the vessel for
the entire cruise.
The weather, sea, and ice conditions will be closely monitored,
including the presence of pack ice that could hinder operation of the
airgun array and streamer(s) as well as conditions that could limit
visibility. If situations are encountered which pose a risk to the
equipment, impede data collection, or require the vessel to stop
forward progress, the equipment will be shut-down and retrieved until
conditions improve. In general, the airgun array and streamer(s) can be
retrieved in less than 30 minutes.
The planned seismic survey (including equipment testing, start-up,
line changes, repeat coverage of any areas, and equipment recovery)
will consist of approximately 1,750 kilometers (km) (944.9 nautical
miles [nmi]) of transect lines (including turns) in the study area in
the Ross Sea (see Figures 1 and 2 of the IHA application). In addition
to the operation of the airgun array, a single-beam and multi-beam
echosounder, ADCP, and a sub-bottom profiler will also likely be
operated from the Palmer continuously throughout the cruise. There will
be additional airgun operations associated with equipment testing,
ramp-up, and possible line changes or repeat coverage of any areas
where initial data quality is sub-standard. In NSF and ASC's estimated
take calculations, 25% has been added for those additional operations.
The portion of the cruise planned for after the low-energy seismic
survey in the Ross Sea is not associated with the project; it is
associated with McMurdo Station support and will occur regardless of
the low-energy seismic survey (i.e., no science activities will be
conducted). In addition, the Palmer will transit approximately 3,980 km
(2,149 nmi) to Australia after the planned support activities for
McMurdo Station.
Table 1--Planned Low-Energy Seismic Survey Activities in the Ross Sea.
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Time between
Survey length (km) Total duration Airgun array total airgun shots Streamer length (m)
(hr) \1\ volume (distance)
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1,750 (944.9 nmi).............. ~200 2 x 105 in\3\ (2 x 5 to 10 seconds 100 (328.1 ft).
1,720 cm\3\). (12.5 to 25 m or
41 to 82 ft).
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\1\ Airgun operations are planned for no more than 100 continuous hours at a time.
NMFS outlined the purpose of the program in a previous notice of
the proposed IHA (79 FR 68512, November 17, 2014). The activities to be
conducted have not changed between the proposed IHA notice and this
final notice announcing the issuance of the IHA. For a more detailed
description of the authorized action, including vessel and acoustic
source specifications, metrics, characteristics of airgun pulses,
predicted sound levels of airguns, bathymetric survey, core sampling,
icebreaking activities, etc., the reader should refer to the notice of
the proposed IHA (79 FR 68512, November 17, 2014), the IHA application,
IEE/EA, EA, and associated documents referenced above this section.
Comments and Responses
A notice of preliminary determinations and proposed IHA for NSF and
ASC's low-energy seismic survey was published in the Federal Register
on November 17, 2014 (79 FR 68512). During the 30-day public comment
period, NMFS received comments from one private citizen and the Marine
Mammal Commission (Commission). The comments are posted online at:
http://www.nmfs.noaa.gov/pr/permits/incidental/. Following are the
substantive comments and NMFS's responses:
Comment 1: The Commission recommends that NMFS adjust density
estimates used to estimate the numbers of potential takes by
incorporating some measure of uncertainty when available density data
originate from other geographical areas and temporal scales and that it
formulate a policy or other guidance setting forth a consistent
approach for how applicants should incorporate uncertainty in density
estimates.
Response: The availability of representative density information
for marine mammal species varies widely across space and time.
Depending on survey locations and modeling efforts, it may be necessary
to consult estimates that are from a different area or season, that are
at a non-ideal spatial scale, or that are several years out of date. As
the Commission notes in their letter to NMFS, we continue to evaluate
available density information and are continuing progress on guidance
that would outline a consistent general approach for addressing
uncertainty in specific situations where certain types of data are or
are not available.
Comment 2: The Commission recommends that NMFS follow a consistent
approach in assessing the potential for taking by Level B
[[Page 4890]]
harassment from exposure to specific types of sound sources (e.g.,
echosounders, sub-bottom profilers, side-scan sonar, and fish-finding
sonar) by all applicants who propose to use them.
Response: NMFS acknowledges the Commission's recommendation and
note that we continue to work on a consistent approach for addressing
potential impacts from active acoustic sources. For this low-energy
seismic survey, NMFS assessed the potential for single-beam and multi-
beam echosounder, ADCP, and sub-bottom profiler operations to impact
marine mammals with the concurrent operation of the airgun array. We
assume that, during simultaneous operations of the airgun array and the
other active acoustic sources, a marine mammal close enough to be
affected by the other active acoustic sources would already be affected
by the airguns. Take is not expected to result from the use of the
single-beam echosounder, multi-beam echosounder, ADCP, and sub-bottom
profiler, as the brief exposure of marine mammals to one pulse, or
small number of signals, to be generated by these instruments in this
particular case as well as their characteristics (e.g., narrow-shaped,
downward-directed beam emitted from the bottom of the ship) is less
likely to result in the harassment of marine mammals. Accordingly, NMFS
will not require a separate assessment of Level B harassment takes for
those sources for this low-energy seismic survey, and NMFS has not
authorized take from these other sound sources.
Comment 3: The Commission recommends that NMFS develop a clear
policy setting forth more explicit criteria and/or thresholds for
making small numbers and negligible impact determinations.
Response: NMFS is required to authorize the take of ``small
numbers'' of a species or stock if the taking (in this case by
harassment) will have a negligible impact on the affected species or
stocks and will not have an unmitigable impact on the availability of
such species or stocks for taking for subsistence purposes. See 16
U.S.C. 1371(a)(5)(D). In determining whether to authorize ``small
numbers'' of a species or stock, NMFS determines whether the numbers of
marine mammals ``taken'' will be small relative to the estimated
population size. Table 5 of this notice reflects that the estimated
take for the entire survey area represents small numbers of marine
mammals relative to the relevant populations. Modeling results,
estimated take numbers, and other analysis do not take into account the
implementation of mitigation measures, which will likely further lower
the numbers of animals taken. NMFS discusses the rationale for our
negligible impact finding in the Analysis and Determinations section.
Comment 4: The Commission is concerned that the L-DEO acoustic
modeling used is not based on the best available science and does not
support its continued use. Therefore, the Commission recommends that
NMFS require NSF and ASC to have L-DEO re-estimate the proposed
exclusion and buffer zones and associated takes of marine mammals using
site-specific environmental (including sound speed profiles,
bathymetry, and sediment characteristics at a minimum) and operational
(including number/type of airguns, tow depth) parameters for the
proposed IHA. The reflective/refractive arrivals are the very
measurements that ultimately determine underwater sound propagation and
should be accounted for in site-specific modeling. Either empirical
measurements from the particular survey site or a model that accounts
for the conditions in the proposed survey area should be used to
estimate exclusion and buffer zones because L-DEO failed to verify the
applicability of its model to conditions outside of the Gulf of Mexico.
The Commission recommends that NMFS impose the same requirements for
all future IHAs submitted by NSF, ASC, L-DEO, USGS, SIO, or any other
relevant entity.
Response: At present, L-DEO cannot adjust its modeling methodology
to add the environmental and site-specific parameters as requested by
the Commission. NMFS is working with L-DEO, NSF, ASC, USGS, SIO, and
any other relevant entity to explore ways to better consider site-
specific information to inform the take estimates and development of
mitigation measures for future seismic surveys with L-DEO and NSF.
Also, NSF has been exploring different approaches in collaboration with
L-DEO and other academic institutions. NMFS will review and consider
the final results from L-DEO's publications (Crone et al., 2013, 2014),
in which the results of a calibration off the coast of Washington have
been reported, and how they reflect on L-DEO's model.
For this seismic survey, L-DEO developed exclusion and buffer zones
based on the conservative deep-water calibration results from Diebold
et al. (2010). L-DEO's current modeling approach represents the best
available information to reach NMFS's determinations for the IHA. The
comparisons of L-DEO's model results and the field data collected in
the Gulf of Mexico illustrate a degree of conservativeness built into
L-DEO's model in deep water.
NMFS acknowledges the Commission's concerns about L-DEO's current
modeling approach for estimating exclusion and buffer zones and also
acknowledge that L-DEO did not incorporate site-specific sound speed
profiles, bathymetry, and sediment characteristics of the research area
within the current approach to estimate those zones for this IHA.
However, as described below, empirical data collected at two different
sites and compared against model predictions indicate that other facets
of the model (besides the site-specific factors cited above) do result
in a conservative estimate of exposures in the cases tested.
The NSF and ASC IHA application and IEE/EA describe the approach to
establishing mitigation exclusion and buffer zones. In summary, L-DEO
acquired field measurements for several array configurations at
shallow- and deep-water depths during acoustic verification studies
conducted in the northern Gulf of Mexico in 2003 (Tolstoy et al., 2004)
and in 2007 and 2008 (Tolstoy et al., 2009). Based on the empirical
data from the studies, L-DEO developed a sound propagation modeling
approach that conservatively predicts received sound levels as a
function of distance from a particular airgun array configuration in
deep water. In 2010, L-DEO assessed the accuracy of their modeling
approach by comparing the sound levels of the field measurements in the
Gulf of Mexico study to its model predictions (Diebold et al., 2010).
L-DEO reported that the observed sound levels from the field
measurements fell almost entirely below the predicted mitigation radii
curve for deep water (Diebold et al., 2010). Based on this information,
L-DEO has shown that its model can reliably estimate the mitigation
radii in deep water and this represents the best available information
to reach the determinations for the subject IHA.
NMFS considered reflected and refracted arrivals in reviewing L-
DEO's model results and field data collected in the Gulf of Mexico and
Washington illustrate a degree of conservativeness built into their
model for deep water. Given that L-DEO demonstrated that the model is
conservative in deep water, NMFS concludes that the L-DEO model is an
effective means to aid in determining potential impacts to marine
mammals from the planned seismic survey and estimating take numbers, as
[[Page 4891]]
well as establishing buffer and exclusion zones for mitigation.
During a March 2013 meeting, L-DEO discussed its model with the
Commission, NMFS, and NSF. L-DEO compared the Gulf of Mexico (GOM)
calibration measurements (Tolstoy et al., 2004; Tolstoy et al., 2009;
Diebold et al., 2010) comparison with L-DEO model results. L-DEO showed
that at the calibration sites the model overestimated the size of the
exclusion zones and, therefore, is likely precautionary in most cases.
Based on the best available information that the current model
overestimates mitigation zones, we did not require L-DEO to re-estimate
the proposed buffer and exclusion zones and associated number of marine
mammal takes using operational and site-specific environmental
parameters for this IHA.
However, we continue to work with the NSF, ASC, L-DEO, and other
related entities on verifying the accuracy of their model. L-DEO is
currently analyzing whether received levels can be measured in real-
time using the ship's hydrophone streamer to estimate the sound field
around the ship and determine actual distances to the buffer and
exclusion zones. Crone et al. (2013 and 2014) are analyzing Marcus G.
Langseth streamer data collected in 2012 off the Washington coast shelf
and slope to measure received levels in situ up to 8 km (4.3 nmi) away
from the ship. While results confirm the role that bathymetry plays in
propagation, it also confirmed that empirical measurements from the
Gulf of Mexico survey used to inform buffer and exclusion zones in
shallow water and model results adapted for intermediate water depths
also over-estimated the size of the zones for the Washington survey.
Preliminary results were presented in a poster session at the American
Geophysical Union fall meeting in December 2013 (Crone et al., 2013;
available at: http://berna.ldeo.columbia.edu/agu2013/agu2013.pdf) and a
peer-reviewed journal publication was published in 2014. NMFS will
review and consider the final results and how they reflect on the L-DEO
model.
L-DEO has conveyed to NMFS that additional modeling efforts to
refine the process and conduct comparative analysis may be possible
with the availability of research funds and other resources. Obtaining
research funds is typically through a competitive process, including
those conducted by federal agencies. The use of models for calculating
buffer and exclusion zone radii and developing take estimates is not a
requirement of the MMPA Incidental Take Authorization (ITA) process.
Furthermore, NMFS does not provide specific guidance on model
parameters nor prescribe a specific model for applicants as part of the
MMPA ITA process. There is a level of variability not only with
parameters in models, but the uncertainty associated with data used in
models, and therefore the quality of the model results submitted by
applicants. NMFS, however, takes all of this variability into
consideration when evaluating applications. Applicants use models as a
tool to evaluate potential impacts, to estimate the number of takes of
marine mammals, and for mitigation purposes. NMFS takes into
consideration the model used and its results in determining the
potential impacts to marine mammals; however, it is just a component of
NMFS's analysis during the MMPA consultation process, as NMFS also
takes into consideration other factors associated with the proposed
action, such as geographic location, duration of activities, context,
intensity, etc. NMFS considers takes generated by modeling as
estimates, not absolutes, and they are factored into NMFS's analysis
accordingly. Of broader note, NMFS is currently pursuing methods that
include site-specific components to allow us to better cross-check
isopleth and propagation predictions submitted by applicants. Using
this information, NMFS could potentially recommend modifications to
take estimates and/or mitigation zones, as appropriate.
Comment 5: The Commission states that NMFS has incorrectly
characterized the Commission's past comments as advocating that
monitoring conducted by an authorized entity always be sufficient to
quantify ``the exact number of takes'' that occurred during the action.
While that may be ideal, the Commission recognizes that it cannot be
achieved regularly in practice. The Commission believes that NMFS
should design monitoring and reporting requirements that provide
considerably more than rough, qualitative information. The specified
monitoring and reporting requirements need to be sufficient to provide
reasonably accurate information on the numbers of marine mammals being
taken and the manner in which they are taken, not merely better
information on the qualitative nature of the impacts.
Also, the Commission recommends that NMFS consult with NSF, ASC,
and other relevant entities (e.g., L-DEO, USGS, SIO) to develop,
validate, and implement a monitoring program that provides a
scientifically sound, reasonably accurate assessment of the types of
marine mammal takes and reliable estimates of the numbers of marine
mammals taken by incorporating applicable g(0) and f(0) values. NMFS
recently stated that it does not generally believe that post-activity
take estimates using f(0) and g(0) are required to meet the monitoring
requirement of the MMPA in the context of the NSF and L-DEO monitoring
plan. However, NMFS did agree that developing and incorporating a way
to better interpret the results of their monitoring (perhaps a
simplified or generalized version of g(0) and f(0) is a good idea. NMFS
further stated that it would consult with the Commission and NMFS
scientists prior to finalizing the recommendations.
Response: As described in this notice, NMFS believes that the model
(used to estimate take), which incorporates animal density, estimated
sound propagation of the source, and predicted total area ensonified
makes a reasonably accurate prediction of the number of animals likely
taken (with the acknowledgement that it does not consider the degree to
which animals might avoid the loud source, which likely results in
somewhat of an overestimate). Post survey, comparing the actual total
area ensonified relative to the predicted area should result in an even
more accurate evaluation of exposed animals, which can then be compared
to the numbers of animals actually detected to get some sense of how
the estimates compare to real likely exposure. Generally for past NSF-
funded seismic surveys, the number of detected marine mammals is a
small percentage of the predicted exposures. This is expected because
marine mammals spend a large portion of their time underwater and they
are not expected to always be seen, but the detections allow us to do a
broad check to ensure that estimates are not grossly off-base, and to
potentially make changes in action or future estimates if appropriate.
In order to make the most accurate estimate of marine mammals based
on visual detections, marine mammal scientists use systematic methods
(on dedicated marine mammal surveys) to consider both the percentage of
time a species spends at the surface (g(0)), as well as the likelihood
of seeing it when it is there (f(0)), which is based on environmental
conditions, observer capabilities, animal characteristics (behavior at
surface, group size, blow size, etc.) distance of animal from the
observer, and other factors. Using all of these factors, combined with
a well-planned randomized sampling design, a correction factor may be
developed to estimate the number of undetected animals based on the
detected animals.
[[Page 4892]]
The Commission suggests that NMFS require something similar of NSF.
Collecting all of the necessary information to inform the development
of such a correction factor (which may include biological information
about less known species in addition to environmental and detection-
based information) to apply to NSF observer detections while also
operating the vessel in the manner necessary to achieve the primary
goal of NSF's survey would be impractical. More importantly, one of the
key factors in developing this type of correction factor is ensuring
that the sampling design doesn't unevenly represent some factor that
actually affects the density of the surveyed animal. In this scenario,
the germane observations are made while the airguns are on, which
clearly effects the density of the animals. While we do know the
direction in which the airgun operation likely affects density of
marine mammals in the vicinity of the source (lowering it), we know
very little else and responses and density in the vicinity to airguns
would vary across species and context (environmental, operational,
animal behavioral state, etc.) in a manner that we do not have the
information to quantify, rendering any such correction factor developed
using information collected during airgun operation inaccurate.
That said, as the Commission notes, there may be some value in
trying to develop some sort of general correction factor for species
that suggests a minimal correction factor that can be justified using,
perhaps, existing information on availability of species for detection
at the surface (if available) or generalized existing information about
sightability at different distances to help estimate likely exposures
post-survey. However, given the information laid out above, combined
with the patchy distribution of marine mammals and their likely overlay
with the relatively narrow strip of water ensonified by the NSF survey,
caution would be warranted in how any resulting post-survey exposure
estimates using such a correction factor were applied. NMFS is open to
considering any specific recommendations that the Commission may have
regarding generalized correction factors based on existing information
and will discuss with the Commission prior to making any
recommendations of this nature to applicants. However, we believe that
requiring NSF to collect information in the field to support the
development of survey-specific correction factors is not appropriate.
Comment 6: One private citizen opposed the issuance of an IHA by
NMFS and the conduct of the low-energy seismic survey in the Ross Sea
by NSF and ASC. The commenter stated that NMFS should protect marine
life from harm.
Response: As described in detail in the notice of the proposed IHA
(79 FR 68512, November 17, 2014), as well as in this document, NMFS
does not believe NSF and ASC's low-energy seismic survey would cause
injury, serious injury, or mortality to marine mammals, and no take by
injury, serious injury, or mortality is authorized. The required
monitoring and mitigation measures that NSF and ASC will implement
during the low-energy seismic survey will further reduce the potential
impacts on marine mammals to the lowest level practicable. NMFS
anticipates only behavioral disturbance to occur during the conduct of
the low-energy seismic survey.
Description of the Marine Mammals in the Specified Geographic Area of
the Specified Activity
Various international and national Antarctic research programs
(e.g., Antarctic Pack Ice Seals Program, Commission for the
Conservation of Antarctic Marine Living Resources, Japanese Whale
Research Program under Special Permit in the Antarctic, and NMFS
National Marine Mammal Laboratory), academic institutions (e.g.,
University of Canterbury, Tokai University, Virginia Institute of
Marine Sciences, University of Genova), and other organizations (e.g.,
National Institute of Water and Atmospheric Research Ltd., Institute of
Cetacean Research, Nippon Kaiyo Co., Ltd., H.T. Harvey & Associates,
Center for Whale Research) have conducted scientific cruises and/or
examined data on marine mammal sightings along the coast of Antarctica,
Southern Ocean, and Ross Sea, and these data were considered in
evaluating potential marine mammals in the planned action area. Records
from the International Whaling Commission's International Decade of
Cetacean Research (IDCR), Southern Ocean Collaboration Program (SOC),
and Southern Ocean Whale and Ecosystem Research (IWC-SOWER) circumpolar
cruises were also considered.
The marine mammals that generally occur in the planned action area
belong to three taxonomic groups: Mysticetes (baleen whales),
odontocetes (toothed whales), and pinnipeds (seals and sea lions). The
marine mammal species that could potentially occur within the Southern
Ocean in proximity to the action area in the Ross Sea include 20
species of cetaceans and 7 species of pinnipeds.
The Ross Sea and surrounding Southern Ocean is a feeding ground for
a variety of marine mammals. In general, many of the species present in
the sub-Antarctic study area may be present or migrating through the
Southern Ocean in the Ross Sea during the planned low-energy seismic
survey. Many of the species that may be potentially present in the
study area seasonally migrate to higher latitudes near Antarctica. In
general, most large whale species (except for the killer whale) migrate
north in the middle of the austral winter and return to Antarctica in
the early austral summer.
The five species of pinnipeds that are found in the Southern Ocean
and will most likely be present in the planned study area include the
crabeater (Lebodon carcinophagus), leopard (Hydrurga leptonyx), Ross
(Ommatophoca rossii), Weddell (Leptonychotes weddellii), and southern
elephant (Mirounga leonina) seal. Many of these pinniped species breed
on either the pack ice or subantarctic islands. Crabeater seals are
more common in the northern regions of the Ross Sea, concentrated in
the pack ice over the Antarctic Slope Front. Leopard seals are often
seen during the austral summer off the Adelie penguin (Pygoscelis
adeliae) rookeries of Ross Island. Ross seals are often found in pack
ice and open waters, they seem to prefer dense consolidated pack ice
rather than the open pack ice that is frequented by crabeater seals.
The Weddell seal is considered to be common and frequently encountered
in the Ross Sea. Southern elephant seals may enter the Ross Sea in the
austral summer from breeding and feeding grounds further to the north.
They are considered uncommon in the Ross Sea. The southern elephant
seal and Antarctic fur seal have haul-outs and rookeries that are
located on subantarctic islands and prefer beaches. Antarctic
(Arctocephalus gazella) and Subantarctic (Arctocephalus tropicalis) fur
seals preferred habitat is not in the proposed study area, and thus it
is not considered further in this document.
Marine mammal species likely to be encountered in the planned study
area that are listed as endangered under the U.S. Endangered Species
Act of 1973 (ESA; 16 U.S.C. 1531 et seq.), includes the southern right
(Eubalaena australis), humpback (Megaptera novaeangliae), sei
(Balaenoptera borealis), fin (Balaenoptera physalus), blue
(Balaenoptera musculus), and sperm (Physeter macrocephalus) whale.
In addition to the 13 species known to occur in the Ross Sea, there
are 7 cetacean species with ranges that are
[[Page 4893]]
known to potentially occur in the waters of the proposed study area:
Southern right, Cuvier's beaked (Ziphius cavirostris), Gray's beaked
(Mesoplodon grayi), Hector's beaked (Mesoplodon hectori), and spade-
toothed beaked (Mesoplodon traversii) whale, southern right whale
dolphin (Lissodelphis peronii), and spectacled porpoise (Phocoena
dioptrica). However, these species have not been sighted and are not
expected to occur where the planned activities will take place. These
species are not considered further in this document. Table 4 (below)
presents information on the habitat, occurrence, distribution,
abundance, population, and conservation status of the species of marine
mammals that may occur in the planned study area during January to
February 2015.
Table 2--The Habitat, Occurrence, Range, Regional Abundance, and Conservation Status of Marine Mammals That May Occur in or Near the Low-Energy Seismic
Survey Area in the Ross Sea
[See text and Tables 6 and 7 in NSF and ASC's IHA application for further details]
--------------------------------------------------------------------------------------------------------------------------------------------------------
Population
Species Habitat Occurrence Range estimate ESA \1\ MMPA \2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Southern right whale (Eubalaena Coastal, pelagic.. Rare.............. Circumpolar 20 to 8,000 \3\ to EN................ D.
australis). 55[deg] South. 15,000 \4\.
Humpback whale (Megaptera Pelagic, nearshore Common............ Cosmopolitan...... 35,000 to 40,000 EN................ D.
novaeangliae). waters, and banks. \3\--Worldwide
9,484 \5\--Scotia
Sea and
Antarctica
Peninsula.
Minke whale (Balaenoptera Pelagic and Common............ Circumpolar--South NA................ NL................ NC.
acutorostrata including dwarf coastal. ern Hemisphere to
sub-species). 65[deg] South.
Antarctic minke whale Pelagic, ice floes Common............ 7[deg] South to Several 100,000 NL................ NC.
(Balaenoptera bonaerensis). ice edge (usually \3\--Worldwide
20 to 65[deg] 18,125 \5\--
South). Scotia Sea and
Antarctica
Peninsula.
Sei whale (Balaenoptera Primarily Uncommon.......... Migratory, Feeding 80,000 \3\-- EN................ D.
borealis). offshore, pelagic. Concentration 40 Worldwide.
to 50[deg] South.
Fin whale (Balaenoptera Continental slope, Common............ Cosmopolitan, 140,000 \3\-- EN................ D.
physalus). pelagic. Migratory. Worldwide 4,672
\5\--Scotia Sea
and Antarctica
Peninsula.
Blue whale (Balaenoptera Pelagic, shelf, Uncommon.......... Migratory Pygmy 8,000 to 9,000 EN................ D.
musculus; including pygmy blue coastal. blue whale--North \3\--Worldwide
whale [Balaenoptera musculus of Antarctic 1,700 \6\--
brevicauda]). Convergence Southern Ocean.
55[deg] South.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter Pelagic, deep sea. Common............ Cosmopolitan, 360,000 \3\-- EN................ D.
macrocephalus). Migratory. Worldwide 9,500
\3\--Antarctic.
Arnoux's beaked whale (Berardius Pelagic........... Common............ Circumpolar in NA................ NL................ NC.
arnuxii). Southern
Hemisphere, 24 to
78[deg] South.
Cuvier's beaked whale (Ziphius Pelagic........... Rare.............. Cosmopolitan...... NA................ NL................ NC.
cavirostris).
Southern bottlenose whale Pelagic........... Common............ Circumpolar--30[de 500,000 \3\--South NL................ NC.
(Hyperoodon planifrons). g] South to ice of Antarctic
edge. Convergence.
Gray's beaked whale (Mesoplodon Pelagic........... Rare.............. 30[deg] South to NA................ NL................ NC.
grayi). Antarctic waters.
Hector's beaked whale Pelagic........... Rare.............. Circumpolar--cool NA................ NL................ NC.
(Mesoplodon hectori). temperate waters
of Southern
Hemisphere.
Spade-toothed beaked whale Pelagic........... Rare.............. Circumantarctic... NA................ NL................ NC.
(Mesoplodon traversii).
Strap-toothed beaked whale Pelagic........... Common............ 30[deg] South to NA................ NL................ NC.
(Mesoplodon layardii). Antarctic
Convergence.
Killer whale (Orcinus orca)..... Pelagic, shelf, Common............ Cosmopolitan...... 80,000 \3\--South NL................ NC.
coastal, pack ice. of Antarctic
Convergence
25,000 \7\--
Southern Ocean.
Long-finned pilot whale Pelagic, shelf, Common............ Circumpolar--19 to 200,000 3 8--South NL................ NC.
(Globicephala melas). coastal. 68[deg] South in of Antarctic
Southern Convergence.
Hemisphere.
[[Page 4894]]
Southern right whale dolphin Pelagic........... Rare.............. 12 to 65[deg] NA................ NL................ NC.
(Lissodelphis peronii). South.
Hourglass dolphin Pelagic, ice edge. Common............ 33[deg] South to 144,000 \3\--South NL................ NC.
(Lagenorhynchus cruciger). pack ice. of Antarctic
Convergence.
Spectacled porpoise (Phocoena Coastal, pelagic.. Rare.............. Circumpolar--South NA................ NL................ NC.
dioptrica). ern Hemisphere.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crabeater seal (Lobodon Coastal, pack ice. Common............ Circumpolar--Antar 5,000,000 to NL................ NC.
carcinophaga). ctic. 15,000,000 3 9--
Worldwide.
Leopard seal (Hydrurga leptonyx) Pack ice, sub- Common............ Sub-Antarctic 220,000 to 440,000 NL................ NC.
Antarctic islands. islands to pack 3 10--Worldwide.
ice.
Ross seal (Ommatophoca rossii).. Pack ice, smooth Common............ Circumpolar--Antar 130,000 \3\ 20,000 NL................ NC.
ice floes, ctic. to 220,000 \14\--
pelagic. Worldwide.
Weddell seal (Leptonychotes Fast ice, pack Common............ Circumpolar--South 500,000 to NL................ NC.
weddellii). ice, sub- ern Hemisphere. 1,000,000 3 11--
Antarctic islands. Worldwide.
Southern elephant seal (Mirounga Coastal, pelagic, Uncommon.......... Circumpolar--Antar 640,000 \12\ to NL................ NC.
leonina). sub-Antarctic ctic Convergence 650,000 \3\--
waters. to pack ice. Worldwide
470,000--South
Georgia Island
\14\.
Antarctic fur seal Shelf, rocky Rare.............. Sub-Antarctic 1,600,000 \13\ to NL................ NC.
(Arctocephalus gazella). habitats. islands to pack 3,000,000 \3\--
ice edge. Worldwide.
Subantarctic fur seal Shelf, rocky Rare.............. Subtropical front Greater than NL................ NC.
(Arctocephalus tropicalis). habitats. to sub-Antarctic 310,000 \3\--
islands and Worldwide.
Antarctica.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, DL = Delisted, NL = Not listed.
\2\ U.S. Marine Mammal Protection Act: D = Depleted, S = Strategic, NC = Not Classified.
\3\ Jefferson et al., 2008.
\4\ Kenney, 2009.
\5\ Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) survey area (Reilly et al., 2004)
\6\ Sears and Perrin, 2009.
\7\ Ford, 2009.
\8\ Olson, 2009.
\9\ Bengston, 2009.
\10\ Rogers, 2009.
\11\ Thomas and Terhune, 2009.
\12\ Hindell and Perrin, 2009.
\13\ Arnould, 2009.
\14\ Academic Press, 2009.
Refer to sections 3 and 4 of NSF and ASC's IHA application for
detailed information regarding the abundance and distribution,
population status, and life history and behavior of these other marine
mammal species and their occurrence in the planned action area. The IHA
application also presents how NSF and ASC calculated the estimated
densities for the marine mammals in the proposed study area. NMFS has
reviewed these data and determined them to be the best available
scientific information for the purposes of the IHA.
Potential Effects of the Specified Activity on Marine Mammals
This section includes a summary and discussion of the ways that the
types of stressors associated with the specified activity (e.g.,
seismic airgun operation, vessel movement, gear deployment, and
icebreaking) have been observed to impact marine mammals. This
discussion may also include reactions that we consider to rise to the
level of a take and those that we do not consider to rise to the level
of take (for example, with acoustics, we may include a discussion of
studies that showed animals not reacting at all to sound or exhibiting
barely measureable avoidance). This section is intended as a background
of potential effects and does not consider either the specific manner
in which this activity will be carried out or the mitigation that will
be implemented, and how either of those will shape the anticipated
impacts from this specific activity. The ``Estimated Take by Incidental
Harassment'' section later in this document will include a quantitative
analysis of the number of individuals that are expected to be taken by
this activity. The ``Negligible Impact Analysis'' section will include
the analysis of how this specific activity will impact marine mammals
and will
[[Page 4895]]
consider the content of this section, the ``Estimated Take by
Incidental Harassment'' section, the ``Mitigation'' section, and the
``Anticipated Effects on Marine Mammal Habitat'' section to draw
conclusions regarding the likely impacts of this activity on the
reproductive success or survivorship of individuals and from that on
the affected marine mammal populations or stocks.
When considering the influence of various kinds of sound on the
marine environment, it is necessary to understand that different kinds
of marine life are sensitive to different frequencies of sound. Based
on available behavioral data, audiograms have been derived using
auditory evoked potentials, anatomical modeling, and other data,
Southall et al. (2007) designate ``functional hearing groups'' for
marine mammals and estimate the lower and upper frequencies of
functional hearing of the groups. The functional groups and the
associated frequencies are indicated below (though animals are less
sensitive to sounds at the outer edge of their functional range and
most sensitive to sounds of frequencies within a smaller range
somewhere in the middle of their functional hearing range):
Low-frequency cetaceans (13 species of mysticetes):
Functional hearing is estimated to occur between approximately 7 Hz and
30 kHz;
Mid-frequency cetaceans (32 species of dolphins, six
species of larger toothed whales, and 19 species of beaked and
bottlenose whales): Functional hearing is estimated to occur between
approximately 150 Hz and 160 kHz;
High-frequency cetaceans (eight species of true porpoises,
six species of river dolphins, Kogia spp., the franciscana [Pontoporia
blainvillei], and four species of cephalorhynchids): Functional hearing
is estimated to occur between approximately 200 Hz and 180 kHz; and
Phocid pinnipeds in water: Functional hearing is estimated
to occur between approximately 75 Hz and 100 kHz;
Otariid pinnipeds in water: Functional hearing is
estimated to occur between approximately 100 Hz and 40 kHz.
As mentioned previously in this document, 18 marine mammal species
(13 cetacean and 5 pinniped species) are likely to occur in the low-
energy seismic survey area. Of the 13 cetacean species likely to occur
in NSF and ASC's action area, 6 are classified as low-frequency
cetaceans (humpback, minke, Antarctic minke, sei, fin, and blue whale),
and 7 are classified as mid-frequency cetaceans (sperm, Arnoux's
beaked, southern bottlenose, strap-toothed beaked, killer, and long-
finned pilot whale, and hourglass dolphin) (Southall et al., 2007). Of
the 5 pinniped species likely to occur in NSF and ASC's action area,
all are classified as phocid pinnipeds (crabeater, leopard, Ross,
Weddell, and southern elephant seal) (Southall et al., 2007). A species
functional hearing group is a consideration when we analyze the effects
of exposure to sound on marine mammals.
Acoustic stimuli generated by the operation of the airguns, which
introduce sound into the marine environment, may have the potential to
cause Level B harassment of marine mammals in the study area. The
effects of sounds from airgun operations might include one or more of
the following: Tolerance, masking of natural sounds, behavioral
disturbance, temporary or permanent hearing impairment, or non-auditory
physical or physiological effects (Richardson et al., 1995; Gordon et
al., 2004; Nowacek et al., 2007; Southall et al., 2007). Permanent
hearing impairment, in the unlikely event that it occurred, would
constitute injury, but temporary threshold shift (TTS) is not an injury
(Southall et al., 2007). Although the possibility cannot be entirely
excluded, it is unlikely that the planned project would result in any
cases of temporary or permanent hearing impairment, or any significant
non-auditory physical or physiological effects. Based on the available
data and studies described here, some behavioral disturbance is
expected, but NMFS expects the disturbance to be localized and short-
term. NMFS described the range of potential effects from the specified
activity in the notice of the proposed IHA (79 FR 68512, November 17,
2014). A more comprehensive review of these issues can be found in the
``Programmatic Environmental Impact Statement/Overseas Environmental
Impact Statement prepared for Marine Seismic Research that is funded by
the National Science Foundation and conducted by the U.S. Geological
Survey'' (NSF/USGS, 2011) and L-DEO's ``Environmental Assessment of a
Marine Geophysical Survey by the R/V Marcus G. Langseth in the Atlantic
Ocean off Cape Hatteras, September to October 2014.''
The notice of the proposed IHA (79 FR 68512, November 17, 2014)
included a discussion of the effects of sounds from airguns,
bathymetric surveys, core sampling, icebreaking activities, and other
acoustic devices and sources on mysticetes and odontocetes, including
tolerance, masking, behavioral disturbance, hearing impairment, and
other non-auditory physical effects. The notice of the proposed IHA (79
FR 68512, November 17, 2014) also included a discussion of the effects
of vessel movement and collisions as well as entanglement. NMFS refers
the readers to NSF and ASC's IHA application and IEE/EA for additional
information on the behavioral reactions (or lack thereof) by all types
of marine mammals to seismic vessels.
Anticipated Effects on Marine Mammal Habitat, Fish, and Invertebrates
NMFS included a detailed discussion of the potential effects of
this action on marine mammal habitat, including physiological and
behavioral effects on marine fish and invertebrates, in the notice of
the proposed IHA (79 FR 68512, November 17, 2014). The low-energy
seismic survey is not anticipated to have any permanent impact on
habitats used by the marine mammals in the study area, including the
food sources they use (i.e., fish and invertebrates). Additionally, no
physical damage to any habitat is anticipated as a result of conducting
airgun operations during the low-energy seismic survey. While NMFS
anticipates that the specified activity may result in marine mammals
avoiding certain areas due to temporary ensonification, this impact to
habitat is temporary and reversible, which was considered in further
detail earlier in the notice of the proposed IHA (79 FR 68512, November
17, 2014), as behavioral modification. The main impact associated with
the planned activity will be temporarily elevated noise levels and the
associated direct effects on marine mammals.
Mitigation
In order to issue an Incidental Take Authorization (ITA) under
section 101(a)(5)(D) of the MMPA, NMFS must set forth the permissible
methods of taking pursuant to such activity, and other means of
effecting the least practicable impact on such species or stock and its
habitat, paying particular attention to rookeries, mating grounds, and
areas of similar significance, and the availability of such species or
stock for taking for certain subsistence uses (where relevant).
NSF and ASC reviewed the following source documents and have
incorporated a suite of appropriate mitigation measures into their
project description.
(1) Protocols used during previous NSF and USGS-funded seismic
research cruises as approved by NMFS and detailed in the ``Final
Programmatic
[[Page 4896]]
Environmental Impact Statement/Overseas Environmental Impact Statement
for Marine Seismic Research Funded by the National Science Foundation
or Conducted by the U.S. Geological Survey;''
(2) Previous IHA applications and IHAs approved and authorized by
NMFS; and
(3) Recommended best practices in Richardson et al. (1995), Pierson
et al. (1998), and Weir and Dolman, (2007).
To reduce the adverse impacts from acoustic stimuli associated with
the planned activities, NSF, ASC, and their designees must implement
the following mitigation measures for marine mammals:
(1) Exclusion zones around the sound source;
(2) Speed and course alterations;
(3) Shut-down procedures; and
(4) Ramp-up procedures.
Exclusion Zones--During pre-planning of the cruise, the smallest
airgun array was identified that could be used and still meet the
geophysical scientific objectives. NSF and ASC use radii to designate
exclusion and buffer zones and to estimate take for marine mammals.
Table 3 (see below) shows the distances at which one would expect to
receive three sound levels (160, 180, and 190 dB) from the two GI
airgun array. The 180 and 190 dB level shut-down criteria are generally
applicable to cetaceans and pinnipeds, respectively, as specified by
NMFS (2000). NSF and ASC used these levels to establish the exclusion
and buffer zones. Table 3. Predicted and modeled (two 105 in\3\ GI
airgun array) distances to which sound levels >= 160, 180, and 190 dB
re 1 [mu]Pa (rms) could be received in deep water during the low-energy
seismic survey in the Ross Sea, January to February 2015.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Predicted RMS radii distances (m) for 2 GI Airgun Array
Source and total volume Tow depth (m) Water depth (m) --------------------------------------------------------------------
160 dB 180 dB 190 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
Two GI Airguns (105 in\3\)......... 3 to 4................ Intermediate (100 to 1,109 (3,638.5 ft)... 111 (364.2 ft)....... 36 (118.1 ft)
1,000). * 100 will be used
for pinnipeds as
described in NSF/
USGS PEIS *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Based on the NSF/USGS PEIS and Record of Decision, for situations
in which incidental take of marine mammals is anticipated, NSF and ASC
have established standard exclusion zones of 100 m for cetaceans and
pinnipeds for all low-energy acoustic sources in water depths greater
than 100 m. While NMFS views the 100 m for pinnipeds appropriate, NMFS
is requiring an exclusion zone of 111 m for cetaceans based on the
predicted and modeled values by L-DEO and to be more conservative. See
below for further explanation.
Received sound levels have been modeled by L-DEO for a number of
airgun configurations, including two 45 in\3\ Nucleus G airguns, in
relation to distance and direction from the airguns (see Figure 2 of
Appendix B of the IHA application). In addition, propagation
measurements of pulses from two GI airguns have been reported for
shallow water (approximately 30 m [98.4 ft] depth) in the GOM (Tolstoy
et al., 2004). However, measurements were not made for the two GI
airguns in deep water. The model does not allow for bottom
interactions, and is most directly applicable to deep water. Based on
the modeling, estimates of the maximum distances from the GI airguns
where sound levels are predicted to be 190, 180, and 160 dB re 1
[micro]Pa (rms) in intermediate water were determined (see Table 3
above).
Empirical data concerning the 190, 180, and 160 dB (rms) distances
were acquired for various airgun arrays based on measurements during
the acoustic verification studies conducted by L-DEO in the northern
GOM in 2003 (Tolstoy et al., 2004) and 2007 to 2008 (Tolstoy et al.,
2009). Results of the 18 and 36 airgun arrays are not relevant for the
two GI airguns to be used in the planned low-energy seismic survey
because the airgun arrays are not the same size or volume. The
empirical data for the 6, 10, 12, and 20 airgun arrays indicate that,
for deep water, the L-DEO model tends to overestimate the received
sound levels at a given distance (Tolstoy et al., 2004). Measurements
were not made for the two GI airgun array in deep water; however, NSF
and ASC plan to use the safety radii predicted by L-DEO's model for the
proposed GI airgun operations in intermediate water, although they are
likely conservative given the empirical results for the other arrays.
Based on the modeling data, the outputs from the pair of 105 in\3\
GI airguns planned to be used during the low-energy seismic survey are
considered a low-energy acoustic source in the NSF/USGS PEIS (2011) for
marine seismic research. A low-energy seismic source was defined in the
NSF/USGS PEIS as an acoustic source whose received level at 100 m is
less than 180 dB. The NSF/USGS PEIS also established for these low-
energy sources, a standard exclusion zone of 100 m for all low-energy
sources in water depths greater than 100 m. This standard 100 m
exclusion zone will be used during the low-energy seismic survey. The
180 and 190 dB (rms) radii are typically used as shut-down criteria
applicable to cetaceans and pinnipeds, respectively; these levels were
used to establish exclusion zones. Therefore, the assumed 180 and 190
dB radii are 100 m for intermediate and deep water. If the PSO detects
a marine mammal within or about to enter the appropriate exclusion
zone, the airguns will be shut-down immediately.
Speed and Course Alterations--If a marine mammal is detected
outside the exclusion zone and, based on its position and direction of
travel (relative motion), is likely to enter the exclusion zone,
changes of the vessel's speed and/or direct course will be considered
if this does not compromise operational safety or damage the deployed
equipment. This will be done if operationally practicable while
minimizing the effect on the planned science objectives. For marine
seismic surveys towing large streamer arrays, course alterations are
not typically implemented due to the vessel's limited maneuverability.
However, the Palmer will be towing a relatively short hydrophone
streamer, so its maneuverability during operations with the hydrophone
streamer will not be limited as vessels towing long streamers, thus
increasing the potential to implement course alterations, if necessary.
After any such speed and/or course alteration is begun, the marine
mammal activities and movements relative to the seismic vessel will be
closely monitored to ensure that the marine mammal does not approach
within the exclusion zone. If the marine mammal appears likely to enter
the exclusion zone, further mitigation actions will be taken, including
further speed and/or course alterations, and/or
[[Page 4897]]
shut-down of the airgun(s). Typically, during airgun operations, the
source vessel is unable to change speed or course, and one or more
alternative mitigation measures will need to be implemented.
Shut-down Procedures--If a marine mammal is detected outside the
exclusion zone for the airgun(s) and the vessel's speed and/or course
cannot be changed to avoid having the animal enter the exclusion zone,
NSF and ASC will shut-down the operating airgun(s) before the animal is
within the exclusion zone. Likewise, if a marine mammal is already
within the exclusion zone when first detected, the seismic source will
be shut-down immediately.
Following a shut-down, NSF and ASC will not resume airgun activity
until the marine mammal has cleared the exclusion zone. NSF and ASC
will consider the animal to have cleared the exclusion zone if:
A PSO has visually observed the animal leave the exclusion
zone, or
A PSO has not sighted the animal within the exclusion zone
for 15 minutes for species with shorter dive durations (i.e., small
odontocetes and pinnipeds), or 30 minutes for species with longer dive
durations (i.e., mysticetes and large odontocetes, including sperm,
killer, and beaked whales).
Although power-down procedures are often standard operating
practice for seismic surveys, they will not be used during this planned
low-energy seismic survey because powering-down from two airguns to one
airgun will make only a small difference in the exclusion zone(s) that
probably will not be enough to allow continued one-airgun operations if
a marine mammal came within the exclusion zone for two airguns.
Ramp-up Procedures--Ramp-up of an airgun array provides a gradual
increase in sound levels, and involves a step-wise increase in the
number and total volume of airguns firing until the full volume of the
airgun array is achieved. The purpose of a ramp-up is to ``warn''
marine mammals in the vicinity of the airguns and to provide the time
for them to leave the area, avoiding any potential injury or impairment
of their hearing abilities. NSF and ASC will follow a ramp-up procedure
when the airgun array begins operating after a specified period without
airgun operations or when a shut-down has exceeded that period. NSF and
ASC proposed that, for the present cruise, this period will be
approximately 15 minutes. SIO, L-DEO, and USGS have used similar
periods (approximately 15 minutes) during previous low-energy seismic
surveys.
Ramp-up will begin with a single GI airgun (105 in\3\). The second
GI airgun (105 in\3\) will be added after 5 minutes. During ramp-up,
the PSOs will monitor the exclusion zone, and if marine mammals are
sighted, a shut-down will be implemented as though both GI airguns were
operational.
If the complete exclusion zone has not been visible for at least 30
minutes prior to the start of operations in either daylight or
nighttime, NSF and ASC will not commence the ramp-up. Given these
provisions, it is likely that the airgun array will not be ramped-up
from a complete shut-down during low light conditions, at night, or in
thick fog, because the outer part of the exclusion zone for that array
will not be visible during those conditions. If one airgun has been
operating, ramp-up to full power will be permissible during low light,
at night, or in poor visibility, on the assumption that marine mammals
will be alerted to the approaching seismic vessel by the sounds from
the single airgun and could move away if they choose. NSF and ASC will
not initiate a ramp-up of the airguns if a marine mammal is sighted
within or near the applicable exclusion zones.
Mitigation Conclusions
NMFS has carefully evaluated the applicant's mitigation measures
and has considered a range of other measures in the context of ensuring
that NMFS prescribes the means of effecting the least practicable
impact on the affected marine mammal species and stocks and their
habitat. NMFS's evaluation of potential measures included consideration
of the following factors in relation to one another:
(1) The manner in which, and the degree to which, the successful
implementation of the measure is expected to minimize adverse impacts
to marine mammals;
(2) The proven or likely efficacy of the specific measure to
minimize adverse impacts as planned; and
(3) The practicability of the measure for applicant implementation
including consideration of personnel safety, practicality of
implementation, and impact on the effectiveness of the activity.
Any mitigation measure(s) prescribed by NMFS should be able to
accomplish, have a reasonable likelihood of accomplishing (based on
current science), or contribute to the accomplishment of one or more of
the general goals listed below:
(1) Avoidance of minimization of injury or death of marine mammals
wherever possible (goals 2, 3, and 4 may contribute to this goal).
(2) A reduction in the numbers of marine mammals (total number or
number at biologically important time or location) exposed to received
levels of airguns, or other activities expected to result in the take
of marine mammals (this goal may contribute to 1, above, or to reducing
harassment takes only).
(3) A reduction in the number of time (total number or number at
biologically important time or location) individuals will be exposed to
received levels of airguns, or other activities expected to result in
the take of marine mammals (this goal may contribute to 1, above, or to
reducing harassment takes only).
(4) A reduction in the intensity of exposures (either total number
or number at biologically important time or location) to received
levels of airguns, or other activities, or other activities expected to
result in the take of marine mammals (this goal may contribute to a,
above, or to reducing the severity of harassment takes only).
(5) Avoidance or minimization of adverse effects to marine mammal
habitat, paying special attention to the food base, activities that
block or limit passage to or from biologically important areas,
permanent destruction of habitat, or temporary destruction/disturbance
of habitat during a biologically important time.
(6) For monitoring directly related to mitigation--an increase in
the probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation.
Based on NMFS's evaluation of the applicant's measures, as well as
other measures considered by NMFS or recommended by the public, NMFS
has determined that the mitigation measures provide the means of
effecting the least practicable impact on marine mammal species or
stocks and their habitat, paying particular attention to rookeries,
mating grounds, and areas of similar significance.
Monitoring and Reporting
In order to issue an ITA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must set forth ``requirements pertaining to
the monitoring and reporting of such taking.'' The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for IHAs
must include the suggested means of accomplishing the necessary
monitoring and reporting that will result in increased knowledge of the
species and of the level of taking or impacts on populations of marine
mammals that are expected to be present in the action area. NSF and ASC
submitted a marine
[[Page 4898]]
mammal monitoring plan as part of the IHA application. It can be found
in Section 13 of the IHA application. The plan has not been modified or
supplemented between the notice of the proposed IHA (79 FR 68512,
November 17, 2014) and this final notice announcing the issuance of the
IHA, as none of the comments or new information received from the
public during the public comment period required a change to the plan.
Monitoring measures prescribed by NMFS should accomplish one or
more of the following general goals:
(1) An increase in the probability of detecting marine mammals,
both within the mitigation zone (thus allowing for more effective
implementation of the mitigation) and in general to generate more data
to contribute to the analyses mentioned below;
(2) An increase in our understanding of how many marine mammals are
likely to be exposed to levels of sound (airguns) that we associate
with specific adverse effects, such as behavioral harassment, TTS, or
PTS;
(3) An increase in our understanding of how marine mammals respond
to stimuli expected to result in take and how anticipated adverse
effects on individuals (in different ways and to varying degrees) may
impact the population, species, or stock (specifically through effects
on annual rates of recruitment or survival) through any of the
following methods:
Behavioral observations in the presence of stimuli
compared to observations in the absence of stimuli (need to be able to
accurately predict received level, distance from source, and other
pertinent information);
Physiological measurements in the presence of stimuli
compared to observations in the absence of stimuli (need to be able to
accurately predict received level, distance from source, and other
pertinent information); and
Distribution and/or abundance comparisons in times or
areas with concentrated stimuli versus times or areas without stimuli
(4) An increased knowledge of the affected species; and
(5) An increase in our understanding of the effectiveness of
certain mitigation and monitoring measures.
Monitoring
NSF and ASC will conduct marine mammal monitoring during the low-
energy seismic survey, in order to implement the mitigation measures
that require real-time monitoring and to satisfy the anticipated
monitoring requirements of the IHA. NSF and ASC's ``Monitoring Plan''
is described below this section. NSF and ASC understand that this
monitoring plan will be subject to review by NMFS and that refinements
may be required. The monitoring work described here has been planned as
a self-contained project independent of any other related monitoring
projects that may be occurring simultaneously in the same regions. NSF
and ASC are prepared to discuss coordination of their monitoring
program with any related work that might be done by other groups
insofar as this is practical and desirable.
Vessel-Based Visual Monitoring
NSF and ASC's PSOs will be based aboard the seismic source vessel
and will watch for marine mammals near the vessel during icebreaking
activities, daytime airgun operations and during any ramp-ups of the
airguns at night. PSOs will also watch for marine mammals near the
seismic vessel for at least 30 minutes prior to the start of airgun
operations and after an extended shut-down (i.e., greater than
approximately 15 minutes for this low-energy seismic survey). When
feasible, PSOs will conduct observations during daytime periods when
the seismic system is not operating (such as during transits) for
comparison of sighting rates and behavior with and without airgun
operations and between acquisition periods. Based on PSO observations,
the airguns will be shut-down when marine mammals are observed within
or about to enter a designated exclusion zone.
During seismic operations in the Ross Sea, at least three PSOs will
be based aboard the Palmer. At least one PSO will stand watch at all
times while the Palmer is operating airguns during the low-energy
seismic survey; this procedure will also be followed when the vessel is
in transit and conducting icebreaking. NSF and ASC will appoint the
PSOs with NMFS's concurrence. The lead PSO will be experienced with
marine mammal species in the Ross Sea and/or Southern Ocean, the second
and third PSOs will receive additional specialized training from the
lead PSO to ensure that they can identify marine mammal species
commonly found in the Ross Sea and Southern Ocean. Observations will
take place during ongoing daytime operations and ramp-ups of the
airguns. During the majority of seismic operations, at least one PSO
will be on duty from observation platforms (i.e., the best available
vantage point on the source vessel) to monitor marine mammals near the
seismic vessel. PSO(s) will be on duty in shifts no longer than 4 hours
in duration. Other crew will also be instructed to assist in detecting
marine mammals and implementing mitigation requirements (if practical).
Before the start of the low-energy seismic survey, the crew will be
given additional instruction on how to do so.
The Palmer is a suitable platform for marine mammal observations
and will serve as the platform from which PSOs will watch for marine
mammals before and during seismic operations. Two locations are likely
as observation stations onboard the Palmer. One observing station is
located on the bridge level, with the PSO eye level at approximately
16.5 m (54.1 ft) above the waterline and the PSO will have a good view
around the entire vessel. In addition, there is an aloft observation
tower for the PSO approximately 24.4 m (80.1 ft) above the waterline
that is protected from the weather, and affords PSOs an even greater
view. The approximate view around the vessel from the bridge is
270[deg] and from the aloft observation tower is 360[deg].
Standard equipment for PSOs will be reticle binoculars. Night-
vision equipment will not be available or necessary as there will be
24-hour daylight or nautical twilight during the cruise. The PSOs will
be in communication with ship's officers on the bridge and scientists
in the vessel's operations laboratory, so they can advise promptly of
the need for avoidance maneuvers or seismic source shut-down. During
daylight, the PSO(s) will scan the area around the vessel
systematically with reticle binoculars (e.g., 7 x 50 Fujinon FMTRC-SX)
and the naked eye. These binoculars will have a built-in daylight
compass. Estimating distances is done primarily with the reticles in
the binoculars. The PSO(s) will be in direct (radio) wireless
communication with ship's officers on the bridge and scientists in the
vessel's operations laboratory during seismic operations, so they can
advise the vessel operator, science support personnel, and the science
party promptly of the need for avoidance maneuvers or a shut-down of
the seismic source. PSOs will monitor for the presence of pinnipeds and
cetaceans during icebreaking activities, and will be limited to those
marine mammal species in proximity to the ice margin habitat.
Observations within the buffer zone will also include pinnipeds that
may be present on the surface of the sea ice (i.e., hauled-out) and
that could potentially dive into the water as the vessel approaches,
indicating disturbance from noise generated by icebreaking activities).
When a marine mammal is detected within or about to enter the
designated exclusion zone, the airguns will immediately be shut-down,
unless the
[[Page 4899]]
vessel's speed and/or course can be changed to avoid having the animal
enter the exclusion zone. The PSO(s) will continue to maintain watch to
determine when the animal is outside the exclusion zone by visual
confirmation. Airgun operations will not resume until the animal is
confirmed to have left the exclusion zone, or is not observed after 15
minutes for species with shorter dive durations (small odontocetes and
pinnipeds) or 30 minutes for species with longer dive durations
(mysticetes and large odontocetes, including sperm, killer, and beaked
whales).
PSO Data and Documentation
PSOs will record data to estimate the numbers of marine mammals
exposed to various received sound levels and to document apparent
disturbance reactions or lack thereof. Data will be used to estimate
numbers of animals potentially ``taken'' by harassment (as defined in
the MMPA). They will also provide information needed to order a shut-
down of the airguns when a marine mammal is within or near the
exclusion zone. Observations will also be made during icebreaking
activities as well as daylight periods when the Palmer is underway
without seismic airgun operations (i.e., transits to, from, and through
the study area) to collect baseline biological data.
When a sighting is made, the following information about the
sighting will be recorded:
1. Species, group size, age/size/sex categories (if determinable),
behavior when first sighted and after initial sighting, heading (if
consistent), bearing and distance from seismic vessel, sighting cue,
apparent reaction to the seismic source or vessel (e.g., none,
avoidance, approach, paralleling, etc.), and behavioral pace.
2. Time, location, heading, speed, activity of the vessel
(including number of airguns operating and whether in state of ramp-up
or shut-down), sea state, wind force, visibility, and sun glare.
The data listed under (2) will also be recorded at the start and
end of each observation watch, and during a watch whenever there is a
change in one or more of the variables.
All observations, as well as information regarding ramp-ups or
shut-downs will be recorded in a standardized format. Data will be
entered into an electronic database. The data accuracy will be verified
by computerized data validity checks as the data are entered and by
subsequent manual checking of the database by the PSOs at sea. These
procedures will allow initial summaries of data to be prepared during
and shortly after the field program, and will facilitate transfer of
the data to statistical, graphical, and other programs for further
processing and archiving.
Results from the vessel-based observations will provide the
following information:
1. The basis for real-time mitigation (airgun shut-down).
2. Information needed to estimate the number of marine mammals
potentially taken by harassment, which must be reported to NMFS.
3. Data on the occurrence, distribution, and activities of marine
mammals in the area where the seismic study is conducted.
4. Information to compare the distance and distribution of marine
mammals relative to the source vessel at times with and without airgun
operations and icebreaking activities.
5. Data on the behavior and movement patterns of marine mammals
seen at times with and without airgun operations and icebreaking
activities.
Reporting
NSF and ASC will submit a comprehensive report to NMFS within 90
days after the end of the cruise. The report will describe the
operations that were conducted and sightings of marine mammals near the
operations. The report submitted to NMFS will provide full
documentation of methods, results, and interpretation pertaining to all
monitoring. The 90-day report will summarize the dates and locations of
seismic operations and all marine mammal sightings (i.e., dates, times,
locations, activities, and associated seismic survey activities). The
report will include, at a minimum:
Summaries of monitoring effort--total hours, total
distances, and distribution of marine mammals through the study period
accounting for Beaufort sea state and other factors affecting
visibility and detectability of marine mammals;
Analyses of the effects of various factors influencing
detectability of marine mammals including Beaufort sea state, number of
PSOs, and fog/glare;
Species composition, occurrence, and distribution of
marine mammals sightings including date, water depth, numbers, age/
size/gender, and group sizes, and analyses of the effects of airgun
operations and icebreaking activities;
Sighting rates of marine mammals during periods with and
without airgun operations and icebreaking activities (and other
variables that could affect detectability);
Initial sighting distances versus airgun operations and
icebreaking activity state;
Closest point of approach versus airgun operations and
icebreaking activity state;
Observed behaviors and types of movements versus airgun
operations and icebreaking activity state;
Numbers of sightings/individuals seen versus airgun
operations and icebreaking activity state; and
Distribution around the source vessel versus airgun
operations and icebreaking activity state.
The report will also include estimates of the number and nature of
exposures that could result in ``takes'' of marine mammals by
harassment or in other ways. NMFS will review the draft report and
provide any comments it may have, and NSF and ASC will incorporate
NMFS's comments and prepare a final report. After the report is
considered final, it will be publicly available on the NMFS Web site
at: http://www.nmfs.noaa.gov/pr/permits/incidental/.
Reporting Prohibited Take--In the unanticipated event that the
specified activity clearly causes the take of a marine mammal in a
manner prohibited by this IHA, such as an injury (Level A harassment),
serious injury or mortality (e.g., ship-strike, gear interaction, and/
or entanglement), NSF and ASC shall immediately cease the specified
activities and immediately report the incident to the Chief of the
Permits and Conservation Division, Office of Protected Resources, NMFS
at 301-427-8401 and/or by email to [email protected] and
[email protected]. The report must include the following
information:
Time, date, and location (latitude/longitude) of the
incident;
Name and type of vessel involved;
Vessel's speed during and leading up to the incident;
Description of the incident;
Status of all sound source use in the 24 hours preceding
the incident;
Water depth;
Environmental conditions (e.g., wind speed and direction,
Beaufort sea state, cloud cover, and visibility);
Description of all marine mammal observations in the 24
hours preceding the incident;
Species identification or description of the animal(s)
involved;
Fate of the animal(s); and
Photographs or video footage of the animal(s) (if
equipment is available).
Activities shall not resume until NMFS is able to review the
circumstances of the prohibited take. NMFS shall work with NSF and ASC
to
[[Page 4900]]
determine what is necessary to minimize the likelihood of further
prohibited take and ensure MMPA compliance. NSF and ASC may not resume
their activities until notified by NMFS via letter or email, or
telephone.
Reporting an Injured or Dead Marine Mammal with an Unknown Cause of
Death--In the event that NSF and ASC discover an injured or dead marine
mammal, and the lead PSO determines that the cause of the injury or
death is unknown and the death is relatively recent (i.e., in less than
a moderate state of decomposition), NSF and ASC shall immediately
report the incident to the Chief of the Permits and Conservation
Division, Office of Protected Resources, NMFS, at 301-427-8401, and/or
by email to [email protected] and [email protected]. The
report must include the same information identified in the paragraph
above. Activities may continue while NMFS reviews the circumstances of
the incident. NMFS shall work with NSF and ASC to determine whether
modifications in the activities are appropriate.
Reporting an Injured or Dead Marine Mammal Not Related to the
Activities--In the event that NSF and ASC discover an injured or dead
marine mammal, and the lead PSO determines that the injury or death is
not associated with or related to the activities authorized in the IHA
(e.g., previously wounded animal, carcass with moderate or advanced
decomposition, or scavenger damage), NSF and ASC shall report the
incident to the Chief of the Permits and Conservation Division, Office
of Protected Resources, NMFS, at 301-427-8401, and/or by email to
[email protected] and [email protected], within 24 hours
of discovery. NSF and ASC shall provide photographs or video footage
(if available) or other documentation of the stranded animal sighting
to NMFS. Activities may continue while NMFS reviews the circumstances
of the incident.
Estimated Take by Incidental Harassment
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as: Any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild [Level A harassment]; or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering [Level B harassment].
Table 4--NMFS's Current Underwater Acoustic Exposure Criteria
----------------------------------------------------------------------------------------------------------------
Impulsive (non-explosive) sound
-----------------------------------------------------------------------------------------------------------------
Criterion Criterion definition Threshold
----------------------------------------------------------------------------------------------------------------
Level A harassment (injury)............. Permanent threshold shift (PTS) 180 dB re 1 [micro]Pa-m (root means
(any level above that which is square [rms]) (cetaceans) 190 dB re
known to cause TTS). 1 [micro]Pa-m (rms) (pinnipeds).
Level B harassment...................... Behavioral disruption (for 160 dB re 1 [micro]Pa-m (rms).
impulsive noise).
Level B harassment...................... Behavioral disruption (for 120 dB re 1 [micro]Pa-m (rms).
continuous noise).
----------------------------------------------------------------------------------------------------------------
Level B harassment is anticipated and authorized as a result of the
low-energy seismic survey in the Ross Sea. Acoustic stimuli (i.e.,
increased underwater sound) generated during the operation of the
seismic airgun array and icebreaking activities are expected to result
in the behavioral disturbance of some marine mammals. There is no
evidence that the planned activities for which NSF and ASC seek the IHA
could result in injury, serious injury, or mortality. The required
mitigation and monitoring measures will minimize any potential risk for
injury, serious injury, or mortality.
The following sections describe NSF and ASC's methods to estimate
take by incidental harassment and present the applicant's estimates of
the numbers of marine mammals that could be affected during the low-
energy seismic survey in the Ross Sea. The estimates are based on a
consideration of the number of marine mammals that could be harassed
during the approximately 200 hours and 1,750 km of seismic airgun
operations with the two GI airgun array to be used and 500 km of
icebreaking activities.
During simultaneous operations of the airgun array and the other
sound sources, any marine mammals close enough to be affected by the
single and multi-beam echosounders, ADCP, or sub-bottom profiler will
already be affected by the airguns. During times when the airguns are
not operating, it is unlikely that marine mammals will exhibit more
than minor, short-term responses to the echosounders, ADCPs, and sub-
bottom profiler given their characteristics (e.g., narrow, downward-
directed beam) and other considerations described previously in the
notice of the proposed IHA (79 FR 68512, November 17, 2014). Therefore,
for this activity, take was not authorized specifically for these sound
sources beyond that which is already planned to be authorized for
airguns and icebreaking activities.
There are no stock assessments and very limited population
information available for marine mammals in the Ross Sea. Published
estimates of marine mammal densities are limited for the planned low-
energy seismic survey's action area. Available density estimates (using
number of animals per km\2\) from the Naval Marine Species Density
Database (NMSDD) (NAVFAC, 2012) were used for one mysticete and one
odontocete (i.e., sei whale and Arnoux's beaked whale). Densities for
minke (including the dwarf sub-species) whales were unavailable and the
densities for Antarctic minke whales were used as proxies.
For other mysticetes and odontocetes, reported sightings data from
one previous research survey (i.e., International Whaling Commission
Southern Ocean Whale and Ecosystem Research [IWC SOWER]) in the Ross
Sea and vicinity were used to identify species that may be present in
the proposed action area and to estimate densities. Available sightings
data from the 2002 to 2003 IWC SOWER Circumpolar Cruise, Area V (Ensor
et al., 2003) were used to estimate densities for five mysticetes
(i.e., humpback, Antarctic minke, minke, fin, and blue whale)and six
odontocetes (i.e., sperm, southern bottlenose, strap-toothed beaked,
killer, long-finned pilot whale and hourglass dolphin). Densities of
pinnipeds (i.e., crabeater, leopard, Ross, Weddell, and southern
elephant seal) were estimated using data from two surveys (NZAI, 2001;
Pinkerton and Bradford-Grieve, n.d.) and dividing the estimated
population of animals by the area of the Ross Sea (approximately
300,000 km\2\ [87,466 nmi\2\]). While these surveys were not
specifically designed to quantify marine mammal densities,
[[Page 4901]]
there was sufficient information to develop density estimates.
The densities used for purposes of estimating potential take do not
take into account the patchy distributions of marine mammals in an
ecosystem, at least on the moderate to fine scales over which they are
known to occur. Instead, animals are considered evenly distributed
throughout the assessed study area and seasonal movement patterns are
not taken into account as none are available.
Some marine mammals that were present in the area during these
surveys may not have been observed. Southwell et al. (2008) suggested a
20 to 40% sighting factor for pinnipeds, and the most conservative
value from Southwell et al. (2008) was applied for cetaceans.
Therefore, the estimated frequency of sightings data in the notice of
the proposed IHA (79 FR 68512, November 17, 2014) and this IHA for
cetaceans incorporates a correction factor of 5, which assumes only 20%
of the animals present were reported due to sea and other environmental
conditions that may have hindered observation, and therefore, there
were 5 times more cetaceans actually present. The correction factor
(20%) was intended to conservatively account for unobserved (i.e., not
sighted and reported) animals.
The pinnipeds that may be present in the study area during the
planned action and are expected to be observed occur mostly near pack
ice, coastal areas, and rocky habitats on the shelf, and are not
prevalent in open sea areas where the low-energy seismic survey will be
conducted. Because density estimates for pinnipeds in the sub-Antarctic
and Antarctic regions typically represent individuals that have hauled-
out of the water, those estimates are not necessarily representative of
individuals that are in the water and could be potentially exposed to
underwater sounds during the seismic airgun operations and icebreaking
activities; therefore, the pinniped densities have been adjusted
downward to account for this consideration. Take was not requested for
Antarctic and Subantarctic seals because preferred habitat for these
species is not within the planned action area. Although there is some
uncertainty about the representativeness of the data and the
assumptions used in the calculations below, the approach used here is
believed to be the best available approach, using the best available
science.
Table 5--Estimated Densities and Possible Number of Marine Mammal Species That Might Be Exposed to Greater Than or Equal to 120 dB (Icebreaking) and 160
dB (Airgun Operations) During NSF and ASC's Low-Energy Seismic Survey (Approximately 500 km of Tracklines/Approximately 21,540 km\2\ Ensonified Area for
Icebreaking Activities and Approximately 1,750 km of Tracklines/Approximately 3,882 km\2\ [1.109 km x 2 x 1,750 km] Ensonified Area for Airgun
Operations) in the Ross Sea, January to February 2015
--------------------------------------------------------------------------------------------------------------------------------------------------------
Calculated Calculated
take from take from
seismic airgun icebreaking
operations operations Approximate
(i.e., (i.e., percentage of
Density (# of estimated estimated Total population Population trend
Species animals/km\2\) number of number of authorized Abundance \4\ estimate \6\
\1\ individuals individuals take (authorized
exposed to exposed to take) \5\
sound levels sound levels
>=160 dB re 1 >=120 dB re 1
[micro]Pa) \2\ [micro]Pa) \3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Southern right whale........... NA 0 0 0 8,000 to 15,000.. NA............... Increasing at 7
to 8% per year.
Humpback whale................. 0.0321169 125 692 817 35,000 to 40,000-- 0.03--Worldwide Increasing.
Worldwide 9,484-- 9.88--Scotia Sea
Scotia Sea and and Antarctic
Antarctica Peninsula.
Peninsula.
Antarctic minke whale.......... 0.0845595 329 1,822 2,151 Several 100,000-- 11.87--Scotia Sea Stable.
Worldwide and Antarctica
18,125--Scotia Peninsula.
Sea and
Antarctica
Peninsula.
Minke whale (including dwarf 0.08455 329 1,822 2,151 NA............... NA............... NA.
minke whale sub-species).
Sei whale...................... 0.0046340 18 100 118 80,000--Worldwide 0.15............. NA
Fin whale...................... 0.0306570 120 661 781 140,000--Worldwid 0.56--Worldwide NA.
e 4,672--Scotia 16.72--Scotia
Sea and Sea and
Antarctica Antarctica
Peninsula. Peninsula.
Blue whale..................... 0.0065132 26 141 167 8,000 to 9,000-- 2.09--Worldwide NA.
Worldwide 1,700-- 9.82--Southern
Southern Ocean. Ocean.
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 4902]]
Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale.................... 0.0098821 39 213 252 360,000--Worldwid 0.07--Worldwide NA.
e 9,500-- 2.65--Antarctic.
Antarctic.
Arnoux's beaked whale.......... 0.0134420 53 290 343 NA............... NA............... NA.
Strap-toothed beaked whale..... 0.0044919 18 97 115 NA............... NA............... NA.
Southern bottlenose whale...... 0.0117912 46 254 300 50,000--South of 0.6.............. NA.
Antarctic
Convergence.
Killer whale................... 0.0208872 82 450 532 80,000--South of 0.67--South of NA.
Antarctic Antarctic
Convergence Convergence
25,000--Southern 2.13--Southern
Ocean. Ocean.
Long-finned pilot whale........ 0.0399777 156 862 1,018 200,000--South of 0.51............. NA.
Antarctic
Convergence.
Hourglass dolphin.............. 0.0189782 74 409 483 144,000--South of 0.34............. NA.
Antarctic
Convergence.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crabeater seal................. 0.6800000 2,640 14,648 17,288 5,000,000 to 0.35............. Increasing.
15,000,000--Worl
dwide.
Leopard seal................... 0.0266700 104 575 679 220,000 to 0.31............. NA.
440,000--Worldwi
de.
Ross seal...................... 0.0166700 65 360 425 130,000.......... 2.13............. NA.
20,000 to
220,000--Worldwi
de.
Weddell seal................... 0.1066700 415 2,298 2,713 500,000 to 0.54............. NA.
1,000,000--World
wide.
Southern elephant seal......... 0.0001300 1 3 4 640,000 to <0.01--Worldwide Increasing,
650,000--Worldwi or South Georgia decreasing, or
de; 470,000-- Island. stable depending
South Georgia on breeding
Island. population.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA = Not available or not assessed.
\1\ Densities based on sightings from IWC SOWER Report 2002, NMSDD, or State of the Ross Sea Region (NZAI, 2001) data.
\2\ Calculated take is estimated density (reported density times correction factor) multiplied by the area ensonified to 160 dB (rms) around the planned
seismic lines, increased by 25% for contingency.
\3\ Calculated take is estimated density (reported density times correction factor) multiplied by the area ensonified to 120 dB (rms) around the planned
transit lines where icebreaking activities may occur.
\4\ See population estimates for marine mammal species in Table 2 (above).
\5\ Total requested authorized takes expressed as percentages of the species or regional populations.
\6\ Jefferson et al. (2008).
Icebreaking in Antarctic waters will occur, as necessary, between
the latitudes of approximately 76 to 78[deg] South and between 165 and
170[deg] West. Based on a historical sea ice extent and the planned
tracklines, it is estimated that the Palmer will actively break ice up
to a distance of 500 km. Based on the ship's speed of 5 kts under
moderate ice
[[Page 4903]]
conditions, this distance represents approximately 54 hours of
icebreaking activities. This calculation is likely an overestimation
because icebreakers often follow leads when they are available and thus
do not break ice at all times. The estimated number of takes for
pinnipeds accounts for both animals that may be in the water and those
hauled-out on ice surfaces. While the number of cetaceans that may be
encountered within the ice margin habitat will be expected to be less
than open water, the estimates utilize densities for open water and
therefore represent conservative estimates.
Numbers of marine mammals that might be present and potentially
disturbed are estimated based on the available data about marine mammal
distribution and densities in the planned Ross Sea study area. NSF and
ASC estimated the number of different individuals that may be exposed
to airgun sounds with received levels greater than or equal to 160 dB
re 1 [mu]Pa (rms) for seismic airgun operations and greater than or
equal to 120 dB re 1 [mu]Pa (rms) for icebreaking activities on one or
more occasions by considering the total marine area that will be within
the 160 dB radius around the operating airgun array and 120 dB radius
for icebreaking activities on at least one occasion and the expected
density of marine mammals in the area (in the absence of the a seismic
survey and icebreaking activities). The number of possible exposures
can be estimated by considering the total marine area that will be
within the 160 dB radius (the diameter is 1,109 m multiplied by 2)
around the operating airguns. The ensonified area for icebreaking was
estimated by multiplying the distance of the icebreaking activities
(500 km) by the estimated diameter for the area within the 120 dB
radius (i.e., diameter is 43.08 km [21.54 km x 2]). The 160 dB radii
are based on acoustic modeling data for the airguns that may be used
during the planned action (see Attachment B of the IHA application). As
summarized in Table 3 (see above and Table 8 of the IHA application),
the modeling results for the planned low-energy seismic airgun array
indicate the received levels are dependent on water depth. Since the
majority of the planned airgun operations will be conducted in waters
100 to 1,000 m deep, the buffer zone of 1,109 m for the two 105 in\3\
GI airguns was used.
The number of different individuals potentially exposed to received
levels greater than or equal to 160 dB re 1 [mu]Pa (rms) from seismic
airgun operations and 120 dB re 1 [mu]Pa (rms) for icebreaking
activities was calculated by multiplying:
(1) The expected species density (in number/km\2\); and
(2) The anticipated area to be ensonified to that level during
airgun operations and icebreaking activities.
Applying the approach described above, approximately 3,882 km\2\
(including the 25% contingency) will be ensonified within the 160 dB
isopleth for seismic airgun operations and approximately 21,540 km\2\
will be ensonified within the 120 dB isopleth for icebreaking
activities on one or more occasions during the planned low-energy
seismic survey. The take calculations within the study sites do not
explicitly add animals to account for the fact that new animals (i.e.,
turnover) not accounted for in the initial density snapshot could also
approach and enter the area ensonified above 160 dB for seismic airgun
operations and 120 dB for icebreaking activities. However, studies
suggest that many marine mammals will avoid exposing themselves to
sounds at this level, which suggests that there will not necessarily be
a large number of new animals entering the area once the seismic survey
and icebreaking activities started. Because this approach for
calculating take estimates does not account for turnover in the marine
mammal populations in the area during the course of the planned low-
energy seismic survey, the actual number of individuals exposed may be
underestimated. However, any underestimation is likely offset by the
conservative (i.e., probably overestimated) line-kilometer distances
(including the 25% contingency) used to calculate the survey area, and
the fact the approach assumes that no cetaceans or pinnipeds will move
away or toward the tracklines as the Palmer approaches in response to
increasing sound levels before the levels reach 160 dB for seismic
airgun operations and 120 dB for icebreaking activities, which is
likely to occur and which will decrease the density of marine mammals
in the survey area. Another way of interpreting the estimates in Table
5 is that they represent the number of individuals that will be
expected (in absence of a seismic and icebreaking program) to occur in
the waters that will be exposed to greater than or equal to 160 dB
(rms) for seismic airgun operations and greater than or equal to 120 dB
(rms) for icebreaking activities.
NSF and ASC's estimates of exposures to various sound levels assume
that the planned low-energy seismic survey will be carried out in full;
however, the ensonified areas calculated using the planned number of
line-kilometers has been increased by 25% to accommodate lines that may
need to be repeated, equipment testing, etc. As is typical during
offshore ship surveys, inclement weather and equipment malfunctions
will be likely to cause delays and may limit the number of useful line-
kilometers of seismic operations that can be undertaken. The estimates
of the numbers of marine mammals potentially exposed to 160 dB (rms)
received levels are precautionary and probably overestimate the actual
numbers of marine mammals that could be involved. These estimates
assume that there will be no weather, equipment, or mitigation delays
that limit the seismic operations, which is highly unlikely.
Table 5 shows the estimates of the number of different individual
marine mammals anticipated to be exposed to greater than or equal to
120 dB re 1 [mu]Pa (rms) for icebreaking activities and greater than or
equal to 160 dB re 1 [mu]Pa (rms) for seismic airgun operations during
the low-energy seismic survey if no animals moved away from the survey
vessel. The total authorized take is given in the column that is fifth
from the left of Table 5.
Encouraging and Coordinating Research
NSF and ASC will coordinate the planned marine mammal monitoring
program associated with the low-energy seismic survey with other
parties that express interest in this activity and area. NSF and ASC
will coordinate with applicable U.S. agencies (e.g., NMFS), and will
comply with their requirements. The action will complement fieldwork
studying other Antarctic ice shelves, oceanographic studies, and
ongoing development of ice sheet and other ocean models. It will
facilitate learning at sea and ashore by students, help to fill
important spatial and temporal gaps in a lightly sampled region of the
Ross Sea, provide additional data on marine mammals present in the Ross
Sea study areas, and communicate its findings concerning the chronology
and cause of eastern Ross Sea grounding-line translations during the
last glacial cycle via reports, publications, and public outreach.
Impact on Availability of Affected Species or Stock for Taking for
Subsistence Uses
Section 101(a)(5)(D) of the MMPA also requires NMFS to determine
that the taking will not have an unmitigable adverse effect on the
availability of marine mammal species or stocks for subsistence use.
There are no relevant subsistence uses of marine mammals
[[Page 4904]]
implicated by this action (in the Ross Sea study area). Therefore, NMFS
has determined that the total taking of affected species or stocks will
not have an unmitigable adverse impact on the availability of such
species or stocks for taking for subsistence purposes.
Analysis and Determinations
Negligible Impact
Negligible impact is ``an impact resulting from the specified
activity that cannot be reasonably expected to, and is not reasonably
likely to, adversely affect the species or stock through effects on
annual rates of recruitment or survival'' (50 CFR 216.103). A
negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of Level B harassment takes,
alone, is not enough information on which to base an impact
determination. In addition to considering estimates of the number of
marine mammals that might be ``taken'' through behavioral harassment,
NMFS must consider other factors, such as the likely nature of any
responses (their intensity, duration, etc.) and the context of any
responses (critical reproductive time or location, migration, etc.), as
well as the number and nature of estimated Level A harassment takes,
the number of estimated mortalities, effects on habitat, and the status
of the species.
In making a negligible impact determination, NMFS evaluated factors
such as:
(1) The number of anticipated serious injuries and or mortalities;
(2) The number and nature of anticipated injuries;
(3) The number, nature, intensity, and duration of takes by Level B
harassment (all of which are relatively limited in this case);
(4) The context in which the takes occur (e.g., impacts to areas of
significance, impacts to local populations, and cumulative impacts when
taking into account successive/contemporaneous actions when added to
baseline data);
(5) The status of stock or species of marine mammals (i.e.,
depleted, not depleted, decreasing, increasing, stable, impact relative
to the size of the population);
(6) Impacts on habitat affecting rates of recruitment/survival; and
(7) The effectiveness of monitoring and mitigation measures.
NMFS has determined that the specified activities associated with
the marine seismic survey are not likely to cause PTS, or other, non-
auditory injury, serious injury, or death, based on the analysis above
and the following factors:
(1) The likelihood that, given sufficient notice through relatively
slow ship speed, marine mammals are expected to move away from a noise
source that is annoying prior to its becoming potentially injurious;
(2) The availability of alternate areas of similar habitat value
for marine mammals to temporarily vacate the survey area during the
operation of the airgun(s) to avoid acoustic harassment;
(3) The potential for temporary or permanent hearing impairment is
relatively low and would likely be avoided through the implementation
of the required monitoring and mitigation measures (including shut-down
measures); and
(4) The likelihood that marine mammal detection ability by trained
PSOs is high at close proximity to the vessel.
No injuries, serious injuries, or mortalities are anticipated to
occur as a result of the NSF and ASC's planned low-energy seismic
survey, and none are authorized by NMFS. Table 5 of this document
outlines the number of authorized Level B harassment takes that are
anticipated as a result of these activities. Due to the nature, degree,
and context of Level B (behavioral) harassment anticipated and
described in this notice (see ``Potential Effects on Marine Mammals''
section above), the activity is not expected to impact rates of annual
recruitment or survival for any affected species or stock, particularly
given the planned mitigation and monitoring measures to minimize
impacts to marine mammals. Additionally, the low-energy seismic survey
will not adversely impact marine mammal habitat.
For the marine mammal species that may occur within the action
area, there are no known designated or important feeding and/or
reproductive areas. Many animals perform vital functions, such as
feeding, resting, traveling, and socializing, on a diel cycle (i.e., 24
hr cycle). Behavioral reactions to noise exposure (such as disruption
of critical life functions, displacement, or avoidance of important
habitat) are more likely to be significant if they last more than one
diel cycle or recur on subsequent days (Southall et al., 2007). While
airgun operations are anticipated to occur on consecutive days, the
estimated duration of the survey will not last more than a total of
approximately 27 operational days. Additionally, the low-energy seismic
survey will be increasing sound levels in the marine environment in a
relatively small area surrounding the vessel (compared to the range of
the animals), which is constantly travelling over distances, so
individual animals likely will only be exposed to and harassed by sound
for less than a day.
As mentioned previously, NMFS estimates that 18 species of marine
mammals under its jurisdiction could be potentially affected by Level B
harassment over the course of the IHA. The population estimates for the
marine mammal species that may be taken by Level B harassment were
provided in Table 2 and 5 of this document. As shown in those tables,
the takes all represent small proportions of the overall populations of
these marine mammal species (i.e., all are less than or equal to 16%).
Of the 18 marine mammal species under NMFS jurisdiction that may or
are known to likely occur in the study area, six are listed as
threatened or endangered under the ESA: Humpback, sei, fin, blue, and
sperm whales. These species are also considered depleted under the
MMPA. None of the other marine mammal species that may be taken are
listed as depleted under the MMPA. Of the ESA-listed species,
incidental take has been authorized for five species. No incidental
take has been authorized for the southern right whale as they are
generally not expected in the proposed action area; however, a few
animals have been sighted in Antarctic waters in the austral summer. To
protect these marine mammals in the study area, NSF and ASC will be
required to cease airgun operations if any marine mammal enters
designated exclusion zones. No injury, serious injury, or mortality is
expected to occur for any of these species, and due to the nature,
degree, and context of the Level B harassment anticipated, and the
activity is not expected to impact rates of recruitment or survival for
any of these species.
NMFS's practice has been to apply the 160 dB re 1 [mu]Pa (rms)
received level threshold for underwater impulse sound levels to
determine whether take by Level B harassment occurs. NMFS has
determined that, provided that the aforementioned mitigation and
monitoring measures are implemented, the impact of conducting a low-
energy marine seismic survey in the Ross Sea, January to February 2015,
may result, at worst, in a modification in behavior and/or low-level
physiological effects (Level B harassment) of certain species of marine
mammals.
While behavioral modifications, including temporarily vacating the
area during the operation of the airgun(s), may be made by these
species to avoid
[[Page 4905]]
the resultant acoustic disturbance, alternate areas are available for
species to move to and the activity's duration is short and sporadic
duration. Due to the nature, degree, and context of Level B
(behavioral) harassment anticipated and described (see ``Potential
Effects on Marine Mammals'' section above) in this notice, the proposed
activity is not expected to impact rates of annual recruitment or
survival for any affected species or stock, particularly given the NMFS
and applicant's plan to implement mitigation and monitoring measures
will minimize impacts to marine mammals. Based on the analysis
contained herein of the likely effects of the specified activity on
marine mammals and their habitat, and taking into consideration the
implementation of the required monitoring and mitigation measures, NMFS
finds that the total marine mammal take from NSF and ASC's low-energy
seismic survey will have a negligible impact on the affected marine
mammal species or stocks.
Small Numbers
As mentioned previously, NMFS estimates that 18 species of marine
mammals under its jurisdiction could be potentially affected by Level B
harassment over the course of the IHA. The population estimates for the
marine mammal species that may be taken by Level B harassment were
provided in Tables 2 and 5 of this document.
The estimated numbers of individual cetaceans and pinnipeds that
could be exposed to seismic sounds with received levels greater than or
equal to 160 dB re 1 [mu]Pa (rms) during the low-energy seismic survey
(including a 25% contingency) and greater than or equal to 120 dB re 1
[mu]Pa (rms) for icebreaking activities are in Table 5 of this
document. Of the cetaceans, 937 humpback, 2,151 Antarctic minke, 2,151
minke, 118 sei, 781 fin, 167 blue, and 252 sperm whales could be taken
by Level B harassment during the planned low-energy seismic survey,
which will represent 9.88, 11.87, unknown, 0.15, 16.72, 9.82, and 2.65%
of the affected worldwide or regional populations, respectively. In
addition, 343 Arnoux's beaked, 115 strap-toothed beaked, and 300
southern bottlenose whales could be taken be Level B harassment during
the planned low-energy seismic survey, which will represent unknown,
unknown, and 0.6% of the affected worldwide or regional populations,
respectively. Of the delphinids, 532 killer whales, 1,018 long-finned
pilot whales, and 483 hourglass dolphins could be taken by Level B
harassment during the planned low-energy seismic survey, which will
represent 2.13, 0.51, and 0.34 of the affected worldwide or regional
populations, respectively. Of the pinnipeds, 17,288 crabeater, 679
leopard, 425 Ross, 2,713 Weddell, and 4 southern elephant seals could
be taken by Level B harassment during the planned low-energy seismic
survey, which will represent 0.35, 0.31, 2.13, 0.54, and <0.01 of the
affected worldwide or regional population, respectively.
No known current worldwide or regional population estimates are
available for 3 species under NMFS's jurisdiction that could
potentially be affected by Level B harassment over the course of the
IHA. These species include the minke, Arnoux's beaked, and strap-
toothed beaked whales. Minke whales occur throughout the North Pacific
Ocean and North Atlantic Ocean and the dwarf sub-species occurs in the
Southern Hemisphere (Jefferson et al., 2008). Arnoux's beaked whales
have a vast circumpolar distribution in the deep, cold waters of the
Southern Hemisphere generally southerly from 34[ordm] South. Strap-
toothed beaked whales are generally found in deep temperate waters
(between 35 to 60[ordm] South) of the Southern Hemisphere (Jefferson et
al., 2008). Based on these distributions and preferences of these
species and the relatively small footprint of the low-energy seismic
survey compared to these distributions, NMFS concludes that the
authorized take of these species likely represent small numbers
relative to the affected species' overall population sizes.
NMFS makes its small numbers determination based on the number of
marine mammals that will be taken relative to the populations of the
affected species or stocks. The authorized take estimates all represent
small numbers relative to the affected species or stock size (i.e., all
are less than or equal to 16%), with the exception of the three species
(i.e., minke, Arnoux's beaked, and strap-toothed beaked whales) for
which a qualitative rationale was provided. Based on the analysis
contained herein of the likely effects of the specified activity on
marine mammals and their habitat, and taking into consideration the
implementation of the mitigation and monitoring measures, NMFS finds
that small numbers of marine mammals will be taken relative to the
populations of the affected species or stocks. See Table 5 for the
authorized take numbers of marine mammals.
Endangered Species Act
Of the species of marine mammals that may occur in the planned
survey area, six are listed as endangered under the ESA: The southern
right, humpback, sei, fin, blue, and sperm whales. Under section 7 of
the ESA, NSF, on behalf of ASC and one other research institution
(Louisiana State University), initiated formal consultation with the
NMFS, Office of Protected Resources, Endangered Species Act Interagency
Cooperation Division, on this low-energy seismic survey. NMFS's Office
of Protected Resources, Permits and Conservation Division, initiated
and engaged in formal consultation under section 7 of the ESA with
NMFS's Office of Protected Resources, Endangered Species Act
Interagency Cooperation Division, on the issuance of an IHA under
section 101(a)(5)(D) of the MMPA for this activity. These two
consultations were consolidated and addressed in a single Biological
Opinion addressing the direct and indirect effects of these independent
actions. In January 2015, NMFS issued a Biological Opinion that
concluded that the action is not likely to jeopardize the continued
existence of the six listed cetaceans that may occur in the study area
and included an Incidental Take Statement (ITS) incorporating the
requirements of the IHA as Terms and Conditions of the ITS. Compliance
with those Terms and Conditions is likewise a mandatory requirement of
the IHA. The Biological Opinion also concluded that designated critical
habitat of these species does not occur in the action area and would
not be affected by the low-energy seismic survey.
National Environmental Policy Act
With NSF and ASC's complete IHA application, NSF and ASC provided
NMFS an ``Initial Environmental Evaluation/Environmental Assessment to
Perform Marine Geophysical Survey, Collect Bathymetric Measurements,
and Conduct Sediment Coring by the RVIB Nathaniel B. Palmer in the Ross
Sea,'' (IEE/EA), prepared by AECOM on behalf of NSF and ASC. The IEE/EA
analyzes the direct, indirect, and cumulative environmental impacts of
the planned specified activities on marine mammals, including those
listed as threatened or endangered under the ESA. NMFS, after
independently reviewing and evaluating the document for sufficiency and
compliance with Council on Environmental Quality (CEQ) NEPA regulations
and NOAA Administrative Order 216-6 Sec. 5.09(d), will conduct a
separate NEPA analysis and has prepared an ``Environmental Assessment
on the Issuance of an Incidental Harassment Authorization to the
National Science Foundation and Antarctic Support Contract to Take
[[Page 4906]]
Marine Mammals by Harassment Incidental to a Low-Energy Marine
Geophysical Survey in the Ross Sea, January to April 2015.'' NMFS has
determined that the issuance of the IHA is not likely to result in
significant impacts on the human environment and issued a Finding of No
Significant Impact (FONSI).
Authorization
NMFS has issued an IHA to NSF and ASC for conducting a low-energy
seismic survey in the Ross Sea, incorporating the previously mentioned
mitigation, monitoring, and reporting requirements.
Dated: January 26, 2015.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2015-01692 Filed 1-28-15; 8:45 am]
BILLING CODE 3510-22-P