Takes of Marine Mammals Incidental to Specified Activities; Low-Energy Marine Geophysical Survey in the Ross Sea, January to February 2015, 4886-4906 [2015-01692]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 80, Number 19 (Thursday, January 29, 2015)]
[Notices]
[Pages 4886-4906]
From the Federal Register Online via the Government Printing 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: https://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: https://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 
(https://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 (https://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)
----------------------------------------------------------------------------------------------------------------
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).
----------------------------------------------------------------------------------------------------------------
\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: 
https://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: https://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: https://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 Jolie.Harrison@noaa.gov and 
Howard.Goldstein@noaa.gov. 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 Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov. 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 
Jolie.Harrison@noaa.gov and Howard.Goldstein@noaa.gov, 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