[Federal Register Volume 85, Number 21 (Friday, January 31, 2020)]
[Notices]
[Pages 5619-5633]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-01811]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XR069]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to THwaites Offshore Research (THOR) 
Project in the Amundsen Sea, Antarctica

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
the National Science Foundation (NSF) Office of Polar Programs on 
behalf of the University of Houston to incidentally harass, by Level B 
harassment only, marine mammals during a low-energy marine geophysical 
survey in the Amundsen Sea, Antarctica.

DATES: This Authorization is effective for one year from the January 
24, 2020.

FOR FURTHER INFORMATION CONTACT: Bonnie DeJoseph, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as a list of the references cited in 
this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these 
documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION: 

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. 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 incidental take authorization may be provided to the public 
for review.
    Authorization for incidental takings shall be granted if NMFS finds 
that the taking will have a negligible impact on the species or 
stock(s) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of the species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of the takings.
    The definitions of all applicable MMPA statutory terms cited above 
are included in the relevant sections below.

Summary of Request

    On July 24, 2019, NMFS received a request from NSF for an IHA to 
take marine mammals incidental to conducting a low-energy marine 
geophysical survey and icebreaking as necessary in the Amundsen Sea. 
The application was deemed adequate and complete on November 22, 2019. 
NSF's request is for take of small numbers of 18 species of marine 
mammals, by harassment. Neither NSF nor NMFS expects serious injury or 
mortality to result from this activity and, therefore, an IHA is 
appropriate. The planned activity is not expected to exceed one year.

Description of Planned Activity

    NSF plans to conduct a low-energy marine seismic survey in the 
Amundsen Sea during February 2020. The survey will complement Thwaites 
Glacier and other Amundsen Sea oceanographic and geological/geophysical 
studies and provide reference data that can be used to initiate and 
evaluate the reliability of ocean models. Data obtained by the project 
would assist in establishing boundary conditions seaward of the 
Thwaites Glacier grounding line, obtaining records of external drivers 
of change, improving knowledge of processes leading to the collapse of 
Thwaites Glacier, and determining the history of past change in 
grounding line migration and conditions at the glacier base.
    Seismic surveys will be conducted over approximately 8400 square 
kilometers (km\2\) between 75.25[deg]-73.5[deg] S and 101.0[deg]-
108.5[deg]W of the Amundsen Sea for approximately eight days beginning 
on or about February 6, 2020. Sixty-five percent of data acquisition 
will occur in intermediate depths (100-1000 meters (m)) and 35 percent 
in deep waters (1000-< 2000 m). The surveys will involve one source 
vessel, the Research Vessel/Icebreaker (RVIB) Nathaniel B. Palmer 
(Palmer). NSF has stated the possibility of deploying multiple 
configurations of generator injector (GI) airgun(s) with one 100-300 m, 
solid-state, hydrophone streamer towed behind the Palmer. If the 
preferred airgun configuration (two 45/105 cubic inch (in\3\) gun array 
in true GI mode does not provide data to meet scientific objectives, 
alternate configurations would be utilized (Table 1). All possible 
configurations will be towed at a depth of 3 m with a total maximum 
discharge volume for the largest, two-airgun array of 420 in\3\ along 
predetermined track lines, approximately 1600 km. Because of the extent 
of sea ice in the Amundsen Sea that typically occurs between January 
and February annually, icebreaking activities are expected to be 
required during the cruise.

[[Page 5620]]



                       Table 1--Proposed Seismic Survey Activities in the Amundsen Sea \1\
----------------------------------------------------------------------------------------------------------------
                                        Airgun array total volume (GI  Frequency between seismic     Streamer
             Configuration                      configuration)                   shots                length
----------------------------------------------------------------------------------------------------------------
Preferred.............................  2 x 45/105 in\3\ (300 in\3\    5 seconds................       100-300 m
                                         total).                                                    (328-984 ft)
                                        (true GI mode)...............
Alternate 1...........................  1 x 45/105 in\3\ (150 in\3\    5 seconds................
                                         total) (true GI mode).
Alternate 2...........................  2 x 105/105 in\3\ (420 in\3\   5 seconds................
(used for take request)...............   total) (harmonic mode).
Alternate 3...........................  1 x 105/105 in\3\ (210 in\3\   5 seconds................
                                         total) (harmonic mode).
----------------------------------------------------------------------------------------------------------------
\1\ Seismic surveying operations are planned for 1600 km (994 mi) in length.

    In addition to the operations of the airgun array, a hull-mounted 
Single Beam Echo Sounder (Knudsen 3260 CHIRP), Multibeam Sonar 
(Kongsberg EM122), Acoustic Doppler Current Profiler (ADCP) (Teledyne 
RDI VM-150 or Ocean Surveyor OS-38), as well as EK biological echo 
sounder (Simrad ES200-7C, ES38B, ES-120-7C) will also be operated from 
the Palmer during the cruise.
    A detailed description of the planned THOR project was provided in 
the Federal Register notice for the proposed IHA published on December 
19, 2019 (84 FR 69950). Since that time, no changes have been made to 
the planned survey activities. Therefore, a detailed description is not 
provided here. Please refer to that Federal Register notice for the 
description of the specific activity.
    Mitigation, monitoring, and reporting measures are described in 
detail later in this document (please see Mitigation and Monitoring and 
Reporting).
BILLING CODE 3510-22-P

[[Page 5621]]

[GRAPHIC] [TIFF OMITTED] TN31JA20.012

BILLING CODE 3510-22-C

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to NSF was published in 
the Federal Register on December 19, 2019 (84 FR 69950). That notice 
described, in detail, NSF's activity, the marine mammal species that 
may be affected by the activity, and the anticipated effects on marine 
mammals. During the 30-day public comment period, NMFS received a 
comment letter from the Marine Mammal Commission (Commission). For full 
detail of the Commission's recommendations and supporting rationale, 
please see the letter (available online at: www.fisheries.noaa.gov/action/incidental-take-authorization-thwaites-offshore-research-thor-project-amundsen-sea-antartica).
    Comment: The Commission recommends that NMFS: (1) Specify whether 
NSF's activities would occur in international waters, the deepest water

[[Page 5622]]

depth in which the geophysical survey would occur, and the parameters 
and methods used to estimate the Level B harassment zone for ice-
breaking activities; (2) use the humpback whale density of 0.001365 
whales/km\2\ based on Gohl (2010) to re-estimate the numbers of takes 
for the geophysical survey and ice-breaking activities; (3)(a) revise 
the (i) Level A and B harassment zones for the geophysical survey based 
on a tow depth of 4 m rather than 3 m or restrict the airguns from 
being towed at a depth of more than 3 m and (ii) ensonified areas for 
Level B harassment based on transiting 200 km rather than 160 km per 
day during the geophysical survey and (b) use the total ensonified area 
for Level B harassment to re-estimate the numbers of takes for the 
geophysical survey; and (4) increase the numbers of Level B harassment 
takes to at least 3 blue whales, 40 humpback whales, 40 killer whales, 
2,000 crabeater seals, 100 Weddell seals, 50 leopard seals, and 10 Ross 
seals based on group size and documented occurrence in the Amundsen 
Sea.
    Response: NSF has confirmed that the survey will occur entirely 
within international waters, and that the maximum survey depth is 1,900 
m. The parameters and methods used to estimate the Level B harassment 
zone for ice-breaking activities are described in the ``Estimated 
Take'' section later in this document. Regarding humpback whale 
density, NMFS concurs with the Commission and has produced revised 
exposure estimates using the recommended density value (see ``Estimated 
Take,'' later in this document). NSF intends to tow the acoustic source 
at a depth of 3 m; therefore, this value was used in modeling of the 
acoustic harassment isopleths. NMFS also concurs with the Commission 
regarding the daily transit distance of 200 km and has revised the 
exposure estimates accordingly. Similarly, exposure estimate 
calculations have been performed using the total ensonified area, as 
recommended by the Commission.
    Regarding the recommendation to increase certain authorized take 
numbers on the basis of expected group size encounters, NMFS concurs 
with the Commission and has made the recommended adjustments, with two 
exceptions. NMFS disagrees with the Commission regarding the likelihood 
of encountering a group of three blue whales, and has retained the 
initial estimate of two. Blue whales, a rarely encountered species, are 
typically encountered as single animals or as small groups of up to 2 
or 3 animals. Therefore, the estimate of two blue whale takes is 
sufficient to account for likely group size. For killer whales, we 
revisited the available information and derived a more appropriate 
density value on the basis of available observational data (as 
described below under ``Changes from the Proposed IHA to Final IHA''). 
The revised exposure estimate exceeds the Commission's recommended 
group size estimate.
    Comment: Regarding ice-breaking, the Commission recommends that 
NMFS use the total ensonified area of 8,491 km\2\ to estimate the 
numbers of Level B harassment takes if ice-breaking activities could 
occur on any of the survey days, or use the reduced ensonified area of 
7,409 km\2\ to estimate the numbers of Level B harassment takes if ice-
breaking activities are expected to occur for two straight days.
    Response: The maximum estimated amount of icebreaking expected by 
NSF, i.e., 445 km for the maximum of 48 hours, was used in our 
calculations to avoid the significant overestimation that would result 
from assuming icebreaking will occur every day (10 survey days, 
including 2 contingency days). It is unlikely that any given animal 
would experience the stressor continuously for 10 days, and the 
potential effects of ice-breaking have been appropriately accounted for 
in NMFS' authorized take levels.
    Comment: The Commission recommends that NMFS (1) include a 
requirement to extrapolate Level B harassment takes to the unobserved 
portions of the Level B harassment zone and (2) ensure that NSF keeps a 
running tally of total Level B harassment takes based on both observed 
and extrapolated takes.
    Response: NMFS agrees that NSF must ensure they do not exceed 
authorized takes. As is typical in such authorizations, we have 
included a requirement that NSF report ``estimates of the number and 
nature of exposures that occurred above the harassment threshold based 
on PSO observations, including an estimate of those that were not 
detected.''
    Comment: The Commission recommends that NMFS require NSF to either 
(1) re-estimate the proposed Level A and B harassment zones and 
associated takes of marine mammals using (a) both operational and site-
specific environmental parameters, (b) a comprehensive source model and 
(c) an appropriate sound propagation model for the proposed incidental 
harassment authorization; or (2) collect or provide the relevant 
acoustic data to substantiate that its modeling approach is 
conservative for both deep and intermediate waters beyond the Gulf of 
Mexico. The Commission further recommends that NMFS (1) explain why it 
believes that sound channels with downward refraction, as well as 
seafloor reflections, are not likely to occur during the geophysical 
survey; (2) specify the degree to which both of those parameters would 
affect the estimation (or underestimation) of Level B harassment zones 
in deep and intermediate water; (3) explain why it believes that NSF's 
model and other `modeling' approaches provide more accurate, realistic, 
and appropriate Level A and B harassment zones than approaches favored 
by the Commission, particularly for deep and intermediate water; and 
(4) explain, if NSF's model and other `modeling' approaches are 
considered best available science, why other action proponents that 
conduct seismic surveys are not implementing similar methods 
particularly given their simplicity.
    Response: As noted by the Commission, these comments reflect a 
longstanding disagreement between NMFS and the Commission regarding 
NSF's approach to modeling the output of their acoustic sources and its 
propagation through the water column. NMFS has previously responded to 
the Commission's comments on NSF's modeling approach. We refer the 
reader to previous Federal Register notices providing responses rather 
than repeat them here (e.g., 84 FR 60059, November 07, 2019; 84 FR 
54849, October 11, 2019; 84 FR 35073, July 22, 2019). However, given 
the Commission's continuing concerns with NSF's modeling approach for 
its broader survey program (and not solely for the subject survey), 
NMFS also will engage separately with the Commission about these 
issues.
    Comment: The Commission recommends that NMFS post on its website 
the same day a notice of proposed authorization publishes in the 
Federal Register the application, the draft incidental harassment 
authorization, any hydroacoustic or marine mammal monitoring plans, its 
list of references, previous monitoring reports, and any other related 
documents.
    Response: NMFS concurs with the recommendation.
    Comment: The Commission reiterates programmatic recommendations 
regarding NMFS' potential use of the renewal mechanism for one-year 
IHAs.
    Response: NMFS disagrees with the Commission's recommendations, as 
stated in our previous comment responses relating to other actions, 
which we incorporate here by reference (e.g., 84 FR 52464; October 02, 
2019).

[[Page 5623]]

Changes From the Proposed IHA to Final IHA

    Corrections have been made to the estimated take table (see Table 
9), as well as population (see Table 2) values updated and density (see 
Table 7) values corrected for two and three species, respectively. More 
recent sources were found for the population abundance of crabeater and 
Weddell seals. Bengston et al. (2011) reported 2,100,000 crabeater 
seals in the Ross and Amundsen Sea, which is more relevant to NSF's 
survey in the Amundsen Sea than Boyd's (2002) report of 5,000,000 seals 
in the entire Antarctic. For Weddell seals, H[uuml]ckst[auml]dt updated 
their population estimate from 750,000 (2015) to 1,000,000 (2018) 
seals.
    We re-evaluated the density values and found that the Protected 
Species Observer Report from a previous NSF Antarctic cruise (Mehle et 
al. 2015) had higher monitoring/observation counts for minke and killer 
whales. Thus, the higher Mehle et al. (2015) counts were used for a 
more conservative take estimate than those used in the proposed IHA; 
i.e., Ainley et al. (2007) for minke whales and NMSDD (2012) for killer 
whales. Since both the Ainley et al. (2007) and Mehle et al. (2015) 
monitoring efforts were conducted from the same vessel, the Palmer, in 
Antarctica, NMFS used the same calculation method as NSF with the 
Ainley et al. (2007) data. Therefore, the 1.6 km visual transect width 
and 556 km survey distance were used to produce the area surveyed, 
889.6 km\2\, which allowed the calculation of the density area.

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history, of the potentially affected species. 
Additional information about these species (e.g., physical and 
behavioral descriptions) may be found on NMFS's website (https://www.fisheries.noaa.gov/find-species).
    The populations of marine mammals considered in this document do 
not occur within the U.S. Exclusive Economic Zone (EEZ) and are 
therefore not assigned to stocks and are not assessed in NMFS' Stock 
Assessment Reports (SAR). As such, information on potential biological 
removal (PBR; defined by the MMPA as the maximum number of animals, not 
including natural mortalities, that may be removed from a marine mammal 
stock while allowing that stock to reach or maintain its optimum 
sustainable population) and on annual levels of serious injury and 
mortality from anthropogenic sources are not available for these marine 
mammal populations. Abundance estimates for marine mammals in the 
survey location are based on a variety of sources including 
International Whaling Commission population estimates (IWC 2019), The 
International Union for Conservation of Nature's (IUCN) Red List of 
Threatened Species, and various literature estimates (see IHA 
application for further detail), as this is considered the best 
available information on potential abundance of marine mammals in the 
area.
    Table 2 lists all species with expected potential for occurrence in 
the Amundsen Sea, Antarctica, and summarizes information related to the 
population, including regulatory status under the MMPA and ESA. For 
taxonomy, we follow the Committee on Taxonomy (2019).

               Table 2--Marine Mammal Species Potentially Present in the Project Area Expected To Be Affected by the Specified Activities
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                            ESA/MMPA status;          Stock
            Common name                  Scientific name              Stock \1\           Strategic  (Y/N) \2\      abundance              PBR
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Family Balaenopteridae (rorquals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Blue whale........................  Balaenoptera musculus....  N/A                      E/D;Y                         \3\ 5,000  N/A
Fin whale.........................  Balaenoptera physalus....  N/A                      E/D;Y                        \4\ 38,200  N/A
Humpback whale....................  Megaptera novaeangliae...  N/A                      -                            \5\ 42,000  N/A
Common (dwarf) minke whale........  Balaenoptera               N/A                      -                           \6\ 257,500  N/A
                                     acutorostrata.
Antarctic minke whale.............  Balaenoptera bonaerensis.  N/A                      -                           \6\ 257,500  N/A
Sei whale.........................  Balaenoptera borealis....  N/A                      E                            \7\ 10,000  N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Family Physeteridae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale.......................  Physeter macrocephalus...  N/A                      E                            \8\ 12,069  N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Family Ziphiidae (beaked whales)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Arnoux's beaked whale.............  Berardius arnuxii........  N/A                      -                           \9\ 599,300  N/A
Gray's beaked whale...............  Mesoplodon grayi.........  N/A                      -                           \9\ 599,300  N/A
Layard's beaked whales............  Mesoplodon layardii......  N/A                      .......................     \9\ 599,300  N/A
Southern bottlenose...............  Hyperoodon planifrons....  N/A                      -                          \10\ 500,000  N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                   Family Delphinidae
--------------------------------------------------------------------------------------------------------------------------------------------------------
Killer whale......................  Orcinus orca.............  N/A                      -                           \11\ 25,000  N/A
Long-finned whale.................  Globicephala               N/A                      -                          \12\ 200,000  N/A
                                     macrorhynchus.
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crabeater seal....................  Lobodon carcinophaga.....  N/A                      -                        \13\ 2,100,000  N/A
Leopard seal......................  Hydrurga leptonyx........  N/A                      -                          \14\ 222,000  N/A

[[Page 5624]]

 
Southern elephant seal............  Mirounga leonina.........  N/A                      -                          \15\ 750,000  N/A
Ross seal.........................  Ommatophoca rossii.......  N/A                      -                          \16\ 250,000  N/A'
Weddell seal......................  Leptonychotes weddellii..  N/A                      -                        \17\ 1,000,000  N/A
--------------------------------------------------------------------------------------------------------------------------------------------------------
N.A. = data not available.
\1\ The populations of marine mammals considered in this document do not occur within the U.S. EEZ and are therefore not assigned to stocks.
\2\ Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
\3\ Antarctic Range 5-8,000 (Cooke 2018).
\4\ Aguilar & Garc[iacute]a-Vernet 2018.
\5\ Partial coverage of Antarctic feeding grounds (IWC 2019).
\6\ Split of undifferentiated minke whale population abundance, total of 515,000 in the Southern Hemisphere (IWC 2019).
\7\ Cooke 2018.
\8\ Estimate for the Antarctic, south of 60[deg] S (Whitehead 2002).
\9\ All beaked whales south of the Antarctic Convergence; mostly southern bottlenose whales (Kasamatsu & Joyce 1995).
\10\ Jefferson et al. 2008.
\11\ Branch & Butterworth 2001.
\12\ Antarctic (Boyd 2002).
\13\ Ross and Amundsen Sea (Bengston et al., 2011).
\14\ Global population is 222,000-440,000 (Rogers 2018).
\15\ Total world population (Hindell et al., 2016)
\16\ H[uuml]ckst[auml]dt 2015.
\17\ H[uuml]ckst[auml]dt 2018.

    All species that could potentially occur in the planned survey 
areas are included in Table 2. As described below, all 18 species 
temporally and spatially co-occur with the activity to the degree that 
take is reasonably likely to occur, and we have authorized it.
    A detailed description of the of the species likely to be affected 
by the THOR geophysical survey, including brief introductions to the 
species and relevant stocks as well as available information regarding 
population trends and threats, information regarding local occurrence, 
and marine mammal hearing were provided in the Federal Register notice 
for the proposed IHA (84 FR 69950; December 19, 2019). Since that time, 
we are not aware of any changes in the status of these species and 
stocks; therefore, detailed descriptions are not provided here. Please 
refer to that Federal Register notice for these descriptions.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from NSF's planned geophysical 
survey have the potential to result in harassment of marine mammals in 
the vicinity of the survey area. The Federal Register notice for the 
proposed IHA (84 FR 69950; December 19, 2019) included a discussion of 
the effects of anthropogenic noise on marine mammals and their habitat. 
That information and analysis is incorporated by reference into this 
final IHA determination and is not repeated here; please refer to that 
Federal Register notice (84 FR 69950; December 19, 2019) for that 
information. No instances of Level A harassment, serious injury or 
mortality are expected as a result of the planned activities.

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform both NMFS' consideration 
of ``small numbers'' and the negligible impact determination.
    Harassment is the only type of take expected to result from these 
activities. Except with respect to certain activities not pertinent 
here, section 3(18) of 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).
    Authorized takes will be by Level B harassment only, in the form of 
disruption of behavioral patterns for individual marine mammals 
resulting from exposure to the acoustic stressors. Based on the nature 
of the acoustic sources planned for this activity (i.e., small Level A 
harassment zones), Level A harassment is neither anticipated, nor 
authorized. In addition, the anticipated effectiveness of the 
mitigation measures (i.e., visual mitigation monitoring; establishment 
of an exclusion zone; shutdown procedures; ramp-up procedures; and 
vessel strike avoidance measures), discussed in detail below in the 
Mitigation section, further reduce the likelihood that Level A 
harassment may occur.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be harassed or incur some degree of 
hearing impairment; (2) the area or volume of water that will be 
ensonified above these levels in a day; (3) the density or occurrence 
of marine mammals within these ensonified areas; and, (4) and the 
number of days of activities. We note that while these basic factors 
can contribute to a basic calculation to provide an initial prediction 
of takes, additional information that can qualitatively inform take 
estimates is also sometimes available (e.g., previous monitoring 
results or average group size). Below, we describe the factors 
considered here in more detail and present the authorized take 
estimate.

[[Page 5625]]

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g., 
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms) 
for non-explosive impulsive (e.g., seismic airguns) or intermittent 
(e.g., scientific sonar) sources.
    NSF's planned activity includes the use of impulsive seismic 
sources and continuous icebreaking, and therefore both 160 dB re 1 
[mu]Pa (rms) and 120 dB re 1 [mu]Pa (rms) are applicable for the 
related activity, respectively.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). NSF's planned activity includes impulsive 
and non-impulsive acoustic sources.
    These thresholds are provided in the table below. The references, 
analysis, and methodology used in the development of the thresholds are 
described in NMFS 2018 Technical Guidance, which may be accessed at 
https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                   PTS onset acoustic thresholds \*\  (received level)
             Hearing group              ------------------------------------------------------------------------
                                                  Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB..
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB..
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB..
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 dB..
----------------------------------------------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever results in the largest isopleth for
  calculating PTS onset. If a non-impulsive sound has the potential of exceeding the peak sound pressure level
  thresholds associated with impulsive sounds, these thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa, and cumulative sound exposure level (LE)
  has a reference value of 1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect American
  National Standards Institute standards (ANSI 2013). However, peak sound pressure is defined by ANSI as
  incorporating frequency weighting, which is not the intent for this Technical Guidance. Hence, the subscript
  ``flat'' is being included to indicate peak sound pressure should be flat weighted or unweighted within the
  generalized hearing range. The subscript associated with cumulative sound exposure level thresholds indicates
  the designated marine mammal auditory weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
  and that the recommended accumulation period is 24 hours. The cumulative sound exposure level thresholds could
  be exceeded in a multitude of ways (i.e., varying exposure levels and durations, duty cycle). When possible,
  it is valuable for action proponents to indicate the conditions under which these acoustic thresholds will be
  exceeded.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of potential take by Level A harassment. However, these 
tools offer the best way to predict appropriate isopleths when more 
sophisticated modeling methods are not available. NMFS continues to 
develop ways to quantitatively refine these tools, and will 
qualitatively address the output where appropriate. For mobile sources 
such as seismic surveys and icebreaking, the User Spreadsheet predicts 
the closest distance at which a stationary animal would not incur PTS 
if the sound source traveled by the animal in a straight line at a 
constant speed. Inputs used in the User Spreadsheet, and the resulting 
isopleths, are reported below in Tables 4, 5, and 6. As noted in Table 
1, the two 45/105 in\3\ GI guns is the preferred configuration for 
NSF's survey. However, values from the GI configuration Alternate 2, 
two 105/105 in\3\ (420 in\3\ total), have been used as the basis for 
modeling and all related take calculations due to its larger volume 
(and greater acoustic output) to present the most conservative modeling 
effort.

                       Table 4--SELcum Methodology
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Source Velocity (meters/second).........................         * 2.315
1/Repetition rate [caret] (seconds).....................            ** 5
------------------------------------------------------------------------
Note: Methodology assumes propagation of 20 log R; Activity duration
  (time) independent.
[caret] Time between onset of successive pulses.
* 4.5 kts.
** shot interval assumed to be 5 seconds.

    Table 5 presents the estimated Level A harassment zones for each 
marine mammal hearing group, which are based on L-DEO modeling 
incorporated into the companion User Spreadsheet (NMFS 2018).

[[Page 5626]]



                    Table 5--Predicted Distances to the Level A Threshold for Marine Mammals
----------------------------------------------------------------------------------------------------------------
                                                  SEL cumulative  SEL cumulative     Peak PTS      Peak PTS \2\
                  Hearing group                    PTS threshold   PTS  distance     threshold     distance  (m)
                                                     (dB) \1\         (m) \1\        (dB) \1\           \1\
----------------------------------------------------------------------------------------------------------------
Low-frequency cetaceans.........................             183            31.1             219            7.55
Mid-frequency cetaceans.........................             185             0.0             230            1.58
Phocid pinnipeds................................             185             0.3             218            8.47
----------------------------------------------------------------------------------------------------------------
\1\ Cumulative sound exposure level for PTS (SELcumPTS) or Peak (SPLflat) resulting in Level A harassment (i.e.,
  injury). Based on 2018 NMFS Acoustic Technical Guidance (NMFS 2018).
\2\ Per NMFS Acoustic Technical Guidance (NMFS 2018), the larger of the dual criteria results are used for the
  EZ; GI configuration Alternate 2, 2 x 105/105 in\3\ (420 in\3\ total).

    Predicted distances to Level A harassment isopleths, which vary 
based on marine mammal hearing groups, were calculated based on 
modeling performed by L-DEO using the NUCLEUS software program and the 
NMFS User Spreadsheet that includes tools to help predict a simple 
isopleth that can be used in conjunction with marine mammal density or 
occurrence to facilitate the estimation of take numbers.
    The predicted distances for Level A harassment are sufficiently 
small (see Table 5), that the likelihood of Level A harassment for any 
marine mammal is considered discountable. Given these small zones and 
the likelihood that any animal would demonstrate aversive behavior to 
the presence of the vessel at such close ranges, it is unrealistic that 
a mammal would stay within such a small area long enough to incur onset 
of PTS. Hence, Level A harassment is not expected or authorized for 
this survey.
    L-DEO's modeling methodology is explained in greater detail in the 
proposed IHA notice (84 FR 69950; December 19, 2019). Please refer to 
NSF's IHA application, Attachment A for the Model Report Estimating the 
Mitigation Zones for Airgun Arrays that could be used in the Amundsen 
Sea, NSF survey. The estimated distances to the Level B harassment 
isopleths for all proposed airgun configurations in each water depth 
category are shown in Table 6.

                         Table 6--Level B--Predicted Distances to the Level B Threshold
                                        (160 re 1[micro]Parms isopleths)
----------------------------------------------------------------------------------------------------------------
                                                                                                Predicted 160 re
               Source and volume (cm\3\)[in\3\]                 Tow depth (m)    Water depth   1[micro]Parms (m)
                                                                                   (m) \1\        isopleth \2\
----------------------------------------------------------------------------------------------------------------
2 x 45/105 in\3\ (300 in\3\) GI guns \*\.....................               3        100-1000               979
                                                               ..............           >1000               653
1 x 45/105 in\3\ (150 in\3\) GI guns ***.....................               3        100-1000               503
                                                               ..............           >1000               335
2 x 105/105 in\3\ (420 in\3\) GI guns **.....................               3        100-1000              1044
                                                               ..............           >1000               696
1 x 105/105 in\3\ (210 in\3\) GI guns ***....................               3        100-1000               531
                                                               ..............           >1000               354
----------------------------------------------------------------------------------------------------------------
\1\ No seismic operations would be conducted in shallow depths (0-100 m).
\2\ RMS radii is based on LDEO modeling and empirical measurements. Radii for 100-1000 m depth values = deep
  water values * 1.5 correction factor.
* Preferred configuration.
** Configuration used in all related take calculations to present the maximum possible effect of the survey.
*** Alternates.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that informed the take 
calculations.
    For the planned survey area in west Antarctica, NSF and NMFS 
determined that the preferred sources of density data for marine mammal 
species that might be encountered in the project area were Ainley et 
al. (2007), Gohl (2010), and Navy Marine Species Density Database 
(2012). Densities were estimated using sightings and effort during 
aerial and vessel-based surveys conducted in and adjacent to the 
proposed project area, as well as from cetacean density models (NMSDD 
2012; see NSF IHA application). NMFS finds the available monitoring 
information from the previous NSF cruise in the Ross Sea (Mehle et al. 
2015), based on their observations of 14 sightings of 254 killer whales 
and 2 blue whales, to support group size and be the most conservative. 
In addition, NMFS included the southern elephant seal to the marine 
mammals potentially present in the project area (Hofmeyr 2015), and 
divided the available minke whale data, which is undifferentiated, into 
the two species that may be affected; Antarctic and Common (dwarf) 
minke whales.
    Since Mehle et al. (2015) reported monitoring information rather 
than specific densities, and both the Ainley et al. (2007) and Mehle et 
al. (2015) monitoring efforts were conducted from the same vessel, the 
Palmer, in Antarctica, NMFS derived density values from Mehle et al. 
(2015) using the same calculation method as was used by NSF to 
calculate density from the Ainley et al. (2007) data. Specifically, we 
used the 1.6 km visual transect width and 556 km survey distance to 
produce 889.6 km \2\ area surveyed, allowing the number of individuals 
sighted to be divided by the area to obtain a density value for each 
relevant species.
    All data sources used for animal abundance are listed in Table 2 
above. Estimated densities used to inform take estimates are presented 
in Table 7.

[[Page 5627]]



      Table 7--Marine Mammal Densities in the Proposed Survey Area
------------------------------------------------------------------------
                                     Areal density
              Species                   (#/km2)          Data source
------------------------------------------------------------------------
                         Low-frequency cetaceans
------------------------------------------------------------------------
Blue whale........................         0.00005  NMSDD 2012
Fin whale.........................         0.00722  NMSDD 2012.
Humpback whale....................         0.00014  Gohl 2010.
Minke whale.......................         1.14996  Mehle et al. 2015.
Antarctic minke whale.............         0.57498  ....................
Common (dwarf) minke whale........         0.57498  ....................
Sei whale.........................         0.00026  NMSDD 2012.
------------------------------------------------------------------------
                         Mid-frequency cetaceans
------------------------------------------------------------------------
Arnoux's beaked whale.............         0.00624  NMSDD 2012.
Killer whale......................         0.28552  NMSDD 2012.
Layard's beaked whale.............         0.00064  Mehle et al. 2015.
Long-finned pilot whale...........         0.00786  NMSDD 2012.
Southern bottlenose whale.........         0.00676  NMSDD 2012.
Sperm whale.......................         0.01699  NMSDD 2012.
Gray's beaked whale...............         0.00028  Ainley et al., 2007.
------------------------------------------------------------------------
                                 Phocids
------------------------------------------------------------------------
Crabeater seal....................         0.00762  Gohl 2010.
Leopard seal......................         0.00005  Gohl 2010.
Ross seal.........................         0.00001  Gohl 2010.
Southern Elephant Seal............         1.03175  Hindell et al.,
                                                     2016.
Weddell seal......................         0.00013  Gohl 2010.
------------------------------------------------------------------------
Notes:
- Where the area surveyed was not indicated in the reference document, a
  value of 315,000 km\2\ was used, estimate of the area of the Amundsen
  Sea Continental shelf (Jacobs 2012).
- NMSDD-Maximum density values during the austral summer for the
  Amundsen Sea (between 100[deg]W-105[deg]W and south of 70[deg]S).

Take Calculation and Estimation

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.

Seismic Surveys

    In order to estimate the number of marine mammals predicted to be 
exposed to sound levels that would result in Level B harassment, radial 
distances from the airgun array to predicted isopleths corresponding to 
the Level B harassment thresholds are calculated, as described in the 
notice of proposed IHA. Those radial distances are then used to 
calculate the area(s) around the airgun array predicted to be 
ensonified to sound levels that exceed the Level B harassment 
thresholds. The area estimated to be ensonified in a single day of the 
survey is then calculated (Table 8), based on the areas predicted to be 
ensonified around the array and the estimated trackline distance 
traveled per day. This number is then multiplied by the number of 
survey days. The product is then multiplied by 1.25 to account for the 
additional 25 percent contingency. This results in an estimate of the 
total area (km \2\) expected to be ensonified to the Level B harassment 
thresholds for each acoustic source (Table 8).

                    Table 8--Areas (km \2\) To Be Ensonified to Level B Harassment Thresholds
----------------------------------------------------------------------------------------------------------------
                                                       Daily
                                   Distance/day     ensonified    Number days of     Plus 25%          Total
            Criteria                   (km)       area w/endcaps      survey      buffer  (days)    ensonified
                                                      (km 2)                                           area
----------------------------------------------------------------------------------------------------------------
                                              LEVEL B Area (160 dB)
----------------------------------------------------------------------------------------------------------------
65% = 100-1000 m................             130          274.86            8.00           10.00        2,748.62
35% = >1000 m...................              70           98.96            8.00           10.00          989.61
                                 -------------------------------------------------------------------------------
ALL DEPTHS......................  ..............  ..............  ..............  ..............        3,738.23
----------------------------------------------------------------------------------------------------------------
                                              Icebreaking (120 dB)
----------------------------------------------------------------------------------------------------------------
                                             223          3003.8            2.00            2.50         7509.49
----------------------------------------------------------------------------------------------------------------

    The marine mammals predicted to occur within these respective 
areas, based on estimated densities (Table 7), are assumed to be 
incidentally taken. As discussed previously, based on the small 
anticipated Level A harassment isopleths and in consideration of the 
mitigation measures (see Mitigation section below), take by Level A

[[Page 5628]]

harassment is not expected to occur and is not authorized. Estimated 
exposures for the planned survey are shown in Table 9.
Icebreaking
    The USCGC Healy served as a proxy for the source levels expected to 
result from icebreaking by the Palmer to calculate the ensonified area 
(Table 8) and Level B take (Table 9): 196.2 db at 1 m source level 
(Roth 2013), transmission loss 20logR, assuming spherical spreading, 
and resulting 6.456 km radius to the 120 dB harassment threshold. The 
maximum estimated amount of icebreaking expected by NSF; i.e. 445 km 
for the maximum of 48 hours, was used in these calculations to avoid 
the significant overestimation of assuming icebreaking will occur every 
day (8 survey days, plus 2 contingency days). We calculate the 
ensonified area associated with icebreaking using the maximum duration 
of 48 hours icebreaking rather than the 10 days of the potential 
survey, as it is unlikely that any given animal would experience the 
stressor continuously for 10 days.
    It should be noted that the authorized take numbers shown in Table 
9 are expected to be conservative because in the calculations of 
estimated take, 25 percent has been added in the form of operational 
survey days. This is to account for the possibility of additional 
seismic operations associated with airgun testing and repeat coverage 
of any areas where initial data quality is sub-standard.
    Following our development of the aforementioned take estimates, and 
based on our review of recommendations from the Marine Mammal 
Commission (described previously in ``Comments and Responses'') we 
increased Level B harassment take estimates for the following species 
as stated here: 40 humpback whales, 2,000 crabeater seals, 100 Weddell 
seals, 50 leopard seals, and 10 Ross seals based on group size and 
documented occurrence in the Amundsen Sea (Gohl 2010).

              Table 9--Calculated and Authorized Level B Exposures, and Percentage of Stock Exposed
----------------------------------------------------------------------------------------------------------------
                                                    Calculated      Calculated
                     Species                       level B take    level B take     Authorized      Percent of
                                                      seismic       icebreaking     total take      population
----------------------------------------------------------------------------------------------------------------
                                             Low-frequency cetaceans
----------------------------------------------------------------------------------------------------------------
Blue whale......................................               1               1               2               0
Fin whale.......................................              27              54              81             0.2
Humpback whale..................................               1               1          40 \b\             0.1
Antarctic minke whale...........................           2,149           4,318           6,467             2.5
Common (dwarf) minke whale......................           2,149           4,318           6,467             2.5
Sei whale.......................................               1               2           6 \a\               0
----------------------------------------------------------------------------------------------------------------
                                             Mid-frequency cetaceans
----------------------------------------------------------------------------------------------------------------
Arnoux's beaked whale...........................              23              47              70               0
Killer whale....................................           1,067           2,144           3,211            12.8
Layard's beaked whale...........................               2               5               7               0
Long-finned pilot whale.........................              29              59              88               0
Southern bottlenose whale.......................              25              51              76               0
Sperm whale.....................................              63             128             191             1.6
Gray's beaked whale.............................               1               2               3               0
----------------------------------------------------------------------------------------------------------------
                                                     Phocids
----------------------------------------------------------------------------------------------------------------
Crabeater seal..................................              28              57       2,000 \c\             0.1
Leopard seal....................................               0               0          50 \c\               0
Ross seal.......................................               0               0          10 \c\               0
Southern elephant Seal..........................           8,897           7,748          16,645             6.7
Weddell seal....................................               0               1         100 \c\               0
----------------------------------------------------------------------------------------------------------------
a. Authorized take increased to group size from W[uuml]rsig et al. (2018).
b. Changed based on recommendation from the MMC based on a group of four whales being taken on each of the 10
  days. Gohl (2010) did not specify the group size of humpback whales observed in the Amundsen Sea, but Thiele
  et al. (2004) documented group size of up to four humpback whales in a given group off the western Antarctic
  Peninsula.
c. Changed based on recommendation from the MMC, the numbers of pinniped takes were based on the relative
  occurrence of the various species based on Gohl (2010). 200 crabeater seals, 10 Weddell seals, 5 leopard
  seals, and 1 Ross seal could be taken on each of the 10 days of activities.

Mitigation Measures

    In order to issue an IHA under Section 101(a)(5)(D) of the MMPA, 
NMFS must set forth the permissible methods of taking pursuant to the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the species or stock for taking for certain 
subsistence uses (latter not applicable for this action). NMFS 
regulations require applicants for incidental take authorizations to 
include information about the availability and feasibility (economic 
and technological) of equipment, methods, and manner of conducting the 
activity or other means of effecting the least practicable adverse 
impact upon the affected species or stocks and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat. 
This considers

[[Page 5629]]

the nature of the potential adverse impact being mitigated (likelihood, 
scope, range). It further considers the likelihood that the measure 
will be effective if implemented (probability of accomplishing the 
mitigating result as planned), the likelihood of effective 
implementation (probability implemented as planned), and;
    (2) the practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.

Mitigation for Marine Mammals and Their Habitat

    NSF has reviewed mitigation measures employed during seismic 
research surveys authorized by NMFS under previous incidental 
harassment authorizations, as well as recommended best practices in 
Richardson et al. (1995), Pierson et al. (1998), Weir and Dolman 
(2007), Nowacek et al. (2013), Wright (2014), and Wright and Cosentino 
(2015), and has incorporated a suite of required mitigation measures 
into their project description based on the above sources.
    To reduce the potential for disturbance from acoustic stimuli 
associated with the activities, NSF is required to implement mitigation 
measures for marine mammals. Mitigation measures that must be adopted 
during the planned surveys include (1) Vessel-based visual mitigation 
monitoring; (2) Establishment of a marine mammal Exclusion Zone (EZ) 
and buffer zone; (3) shutdown procedures; (4) ramp-up procedures; and 
(4) vessel strike avoidance measures.

Vessel-Based Visual Mitigation Monitoring

    Visual monitoring requires the use of trained observers (herein 
referred to as visual Protected Species Observers (PSOs)) to scan the 
ocean surface visually for the presence of marine mammals. PSO(s) must 
be on duty and conducting visual observations at all times during 
daylight hours (i.e., from 30 minutes prior to sunrise through 30 
minutes following sunset). Following a shutdown for any reason, 
observations must occur for at least 30 minutes prior to the planned 
start of airgun operations. Observations must also occur for 60 minutes 
after airgun operations cease for any reason (or until 30 minutes 
following sunset). Observations must also be made during daytime 
periods when the Palmer is underway without seismic operations, such as 
during transits, to allow for comparison of sighting rates and behavior 
with and without airgun operations and between acquisition periods. 
Airgun operations must be suspended when marine mammals are observed 
within, or about to enter, the designated EZ (as described below).
    During seismic operations, three visual PSOs must be based aboard 
the Palmer. PSOs must be appointed by NSF with NMFS approval. One 
dedicated PSO must monitor the EZ during all daytime seismic 
operations. PSO(s) must be on duty in shifts of duration no longer than 
four hours. Other vessel crew must also be instructed to assist in 
detecting marine mammals and in implementing mitigation requirements 
(if practical). Before the start of the seismic survey, the crew must 
be given additional instruction in detecting marine mammals and 
implementing mitigation requirements.
    The Palmer is a suitable platform from which PSOs will watch for 
marine mammals. Standard equipment for marine mammal observers must be 
7 x 50 reticule binoculars and optical range finders. At night, night-
vision equipment must be available. The observers must 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 shutdown.
    The PSOs must have no tasks other than to conduct observational 
effort, record observational data, and communicate with and instruct 
relevant vessel crew with regard to the presence of marine mammals and 
mitigation requirements. PSO resumes must be provided to NMFS for 
approval. At least one PSO must have a minimum of 90 days at-sea 
experience working as a PSO during a seismic survey. One 
``experienced'' visual PSO must be designated as the lead for the 
entire protected species observation team. The lead will serve as 
primary point of contact for the vessel operator.

Exclusion Zone and Buffer Zone

    An EZ is a defined area within which occurrence of a marine mammal 
triggers mitigation action intended to reduce the potential for certain 
outcomes, e.g., auditory injury, severe behavioral reaction. The PSOs 
must establish a minimum EZ with a 100 m radius for the airgun array. 
The EZs must be based on radial distance from any element of the airgun 
array (rather than being based on the center of the array or around the 
vessel itself). With certain exceptions (described below), if a marine 
mammal appears within or enters this zone, the acoustic source must be 
shut down (see Shutdown Procedures below).
    The 100-m radial distance of the standard EZ is precautionary in 
the sense that it is expected to contain sound exceeding injury 
criteria for all marine mammal hearing groups (Table 3) while also 
providing a consistent, reasonably observable zone within which PSOs 
will typically be able to conduct effective observational effort. In 
this case, the 100-m radial distance is also expected to contain sound 
that will exceed the Level A harassment threshold based on sound 
exposure level (SELcum) criteria for all marine mammal 
hearing groups (Table 3).
    Our intent in prescribing a standard EZ distance is to (1) 
encompass zones within which auditory injury could occur on the basis 
of instantaneous exposure; (2) provide additional protection from the 
potential for more severe behavioral reactions (e.g., panic, 
antipredator response) for marine mammals at relatively close range to 
the acoustic source; (3) provide consistency for PSOs, who need to 
monitor and implement the EZ; and (4) define a distance within which 
detection probabilities are reasonably high for most species under 
typical conditions.
    PSOs will also establish and monitor an additional buffer to the 
exclusion zone, i.e., must monitor the 100-m exclusion zone plus an 
additional 100-m buffer for a total of 200 m. During use of the 
acoustic source, occurrence of marine mammals within the buffer zone 
(but outside the EZ) will be communicated to the operator to prepare 
for potential shutdown of the acoustic source. In context of the larger 
extended EZ (discussed in the following paragraph), the buffer zone is 
largely applicable to the pre-clearance period prior to beginning the 
ramp-up procedure (as discussed further under Ramp-up Procedures, later 
in this section).
    An extended EZ of 500 m must be enforced for all beaked whales and 
for Southern right whales. The latter is a precautionary measure as 
right whales are not expected in the survey area. NSF will also 
implement a 500-m EZ for aggregations of six or more large whales 
(i.e., sperm whale or any baleen whale) or a large whale with a calf 
(calf defined as an animal less than two-thirds the body size of an 
adult observed to be in close association with an adult).

Shutdown Procedures

    If a marine mammal appears within or enters the relevant EZ, the 
airguns must

[[Page 5630]]

be shut down. Following a shutdown, airgun activity must not resume 
until the marine mammal has cleared the relevant EZ. The animal is 
considered to have cleared the EZ if the following conditions have been 
met:
     it is visually observed to have departed the EZ;
     it has not been seen within the EZ for 15 minutes in the 
case of small odontocetes and pinnipeds; or
     it has not been seen within the EZ for 30 minutes in the 
case of mysticetes and large odontocetes, including sperm and beaked 
whales.
    Shutdown of the acoustic source is required upon observation of a 
species for which authorization has not been granted, or a species for 
which authorization has been granted but the authorized number of takes 
are met, observed entering or within the Level B harassment zone.

Ramp-Up Procedures

    Ramp-up of an acoustic source is intended to provide a gradual 
increase in sound levels following a shutdown, enabling animals to move 
away from the source if the signal is sufficiently aversive prior to 
its reaching full intensity. Ramp-up is required after the array is 
shut down for any reason for longer than 15 minutes. Ramp-up must begin 
with the activation of the smallest airgun in the array, with 
subsequent airgun(s) activated after 5 minute intervals.
    Two PSOs are required to monitor during ramp-up. During ramp up, 
the PSOs must monitor the EZ, and if marine mammals were observed 
within the EZ, a shutdown will be implemented as though the full array 
were operational. If airguns have been shut down due to PSO detection 
of a marine mammal within or approaching the EZ, ramp-up must not be 
initiated until all marine mammals have cleared the EZ, during the day 
or night. Criteria for clearing the EZ is described above.
    Thirty minutes of pre-clearance observation are required prior to 
ramp-up for any shutdown of longer than 30 minutes (e.g., when the 
array is shut down during transit from one line to another). This 30-
minute pre-clearance period may occur during any vessel activity (i.e., 
transit). If a marine mammal were observed within or approaching the 
relevant EZ during this pre-clearance period, ramp-up must not be 
initiated until all marine mammals cleared the EZ. Criteria for 
clearing the EZ must be as described above. If the airgun array has 
been shut down for reasons other than mitigation (e.g., mechanical 
difficulty) for a period of less than 30 minutes, it may be activated 
again without ramp-up if PSOs have maintained constant visual 
observation and no detections of any marine mammal have occurred within 
the EZ or buffer zone. Ramp-up must be planned to occur during periods 
of good visibility when possible. However, ramp-up will be allowed at 
night and during poor visibility if the 100 m EZ and buffer zone have 
been monitored by visual PSOs for 30 minutes prior to ramp-up.
    The operator is required to notify a designated PSO of the planned 
start of ramp-up as agreed-upon with the lead PSO; the notification 
time should not be less than 60 minutes prior to the planned ramp-up. A 
designated PSO must be notified again immediately prior to initiating 
ramp-up procedures and the operator must receive confirmation from the 
PSO to proceed. The operator must provide information to PSOs 
documenting that appropriate procedures were followed. Following 
deactivation of the array for reasons other than mitigation, the 
operator is required to communicate the near-term operational plan to 
the lead PSO with justification for any planned nighttime ramp-up.

Vessel Strike Avoidance Measures

    Vessel strike avoidance measures are intended to minimize the 
potential for collisions with marine mammals. These requirements do not 
apply in any case where compliance will create an imminent and serious 
threat to a person or vessel or to the extent that a vessel is 
restricted in its ability to maneuver and, because of the restriction, 
cannot comply.
    The required measures include the following: Vessel operator and 
crew must maintain a vigilant watch for all marine mammals and slow 
down or stop the vessel or alter course to avoid striking any marine 
mammal. A visual observer aboard the vessel must monitor a vessel 
strike avoidance zone around the vessel according to the parameters 
stated below. Visual observers monitoring the vessel strike avoidance 
zone must be either third-party observers or crew members, but crew 
members responsible for these duties must be provided sufficient 
training to distinguish marine mammals from other phenomena. Vessel 
strike avoidance measures must be followed during surveys and while in 
transit.
    The vessel must maintain a minimum separation distance of 100 m 
from large whales (i.e., baleen whales and sperm whales). If a large 
whale is within 100 m of the vessel, the vessel must reduce speed and 
shift the engine to neutral, and must not engage the engines until the 
whale has moved outside of the vessel's path and the minimum separation 
distance has been established. If the vessel is stationary, the vessel 
must not engage engines until the whale(s) has moved out of the 
vessel's path and beyond 100 m. The vessel must, to the maximum extent 
practicable, attempt to maintain a minimum separation distance of 50 m 
from all other marine mammals. If an animal is encountered during 
transit, the vessel must attempt to remain parallel to the animal's 
course, avoiding excessive speed or abrupt changes in course. Vessel 
speeds must be reduced to 10 kts or less when mother/calf pairs, pods, 
or large assemblages of cetaceans are observed near the vessel.
    Based on our evaluation of the applicant's required measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
required mitigation measures provide the means effecting the least 
practicable impact on the affected 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 IHA 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 
authorizations 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 
planned action area. Effective reporting is critical both to compliance 
as well as ensuring that the most value is obtained from the required 
monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density).
     Nature, scope, or context of likely marine mammal exposure 
to potential stressors/impacts (individual or cumulative, acute or 
chronic), through better understanding of: (1) Action or environment 
(e.g., source characterization, propagation, ambient noise); (2) 
affected species (e.g., life history, dive patterns); (3) co-occurrence 
of marine mammal species with the

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action; or (4) biological or behavioral context of exposure (e.g., age, 
calving or feeding areas).
     Individual marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors.
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks.
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat).
     Mitigation and monitoring effectiveness.
    NSF described a marine mammal monitoring and reporting plan within 
their IHA application. Monitoring that is designed specifically to 
facilitate mitigation measures, such as monitoring of the EZ to inform 
potential shutdowns of the airgun array, are described above and are 
not repeated here. NSF's monitoring and reporting plan includes the 
following measures:

Vessel-Based Visual Monitoring

    As described above, PSO observations must take place during daytime 
airgun operations and nighttime start-ups (if applicable) of the 
airguns. During seismic operations, three visual PSOs must be based 
aboard the Palmer. PSOs must be appointed by NSF with NMFS approval. 
The PSOs must have successfully completed relevant training, including 
completion of all required coursework and passing a written and/or oral 
examination developed for the training program, and must have 
successfully attained a bachelor's degree from an accredited college or 
university with a major in one of the natural sciences and a minimum of 
30 semester hours or equivalent in the biological sciences and at least 
one undergraduate course in math or statistics. The educational 
requirements may be waived if the PSO has acquired the relevant skills 
through alternate training, including (1) secondary education and/or 
experience comparable to PSO duties; (2) previous work experience 
conducting academic, commercial, or government-sponsored marine mammal 
surveys; or (3) previous work experience as a PSO; the PSO should 
demonstrate good standing and consistently good performance of PSO 
duties.
    During seismic operations, one PSO is required to monitor for 
marine mammals around the vessel. PSOs must be on duty in shifts of 
duration no longer than four hours. Other crew must also be instructed 
to assist in detecting marine mammals and in implementing mitigation 
requirements (if practical). During daytime, PSOs must scan the area 
around the vessel systematically with reticle binoculars (e.g., 7x50 
Fujinon) and with the naked eye. At night, PSOs must be equipped with 
night-vision equipment.
    PSOs must 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 must be used to estimate 
numbers of animals potentially `taken' by harassment (as defined in the 
MMPA). They must also provide information needed to order a shutdown of 
the airguns when a marine mammal is within or near the EZ. When a 
sighting is made, the following information about the sighting must 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 airguns or vessel (e.g., none, avoidance, 
approach, paralleling, etc.), and behavioral pace; and
    (2) Time, location, heading, speed, activity of the vessel, sea 
state, visibility, and sun glare.
    All observations and shutdowns must be recorded in a standardized 
format. Data must be entered into an electronic database. The accuracy 
of the data entry must be verified by computerized data validity checks 
as the data are entered and by subsequent manual checking of the 
database. These procedures allow initial summaries of data to be 
prepared during and shortly after the field program and facilitate 
transfer of the data to statistical, graphical, and other programs for 
further processing and archiving. The time, location, heading, speed, 
activity of the vessel, sea state, visibility, and sun glare must 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.
    Results from the vessel-based observations must provide:
    (1) The basis for real-time mitigation (e.g., airgun shutdown);
    (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 seismic 
activity; and
    (5) Data on the behavior and movement patterns of marine mammals 
seen at times with and without seismic activity.

Reporting

    A draft report must be submitted to NMFS within 90 days after the 
end of the survey. The report must describe the operations that were 
conducted and sightings of marine mammals near the operations. The 
report must provide full documentation of methods, results, and 
interpretation pertaining to all monitoring and will summarize the 
dates and locations of seismic operations, and all marine mammal 
sightings (dates, times, locations, activities, associated seismic 
survey activities). The report must also include estimates of the 
number and nature of exposures that occurred above the harassment 
threshold based on PSO observations, including an estimate of those 
that were not detected in consideration of both the characteristics and 
behaviors of the species of marine mammals that affect detectability, 
as well as the environmental factors that affect detectability.
    The draft report must also include geo-referenced time-stamped 
vessel tracklines for all time periods during which airguns were 
operating. Tracklines must include points recording any change in 
airgun status (e.g., when the airguns began operating, when they were 
turned off, or when they changed from full array to single gun or vice 
versa). GIS files must be provided in ESRI shapefile format and include 
the UTC date and time, latitude in decimal degrees, and longitude in 
decimal degrees. All coordinates must be referenced to the WGS84 
geographic coordinate system. In addition to the report, all raw 
observational data must be made available to NMFS. A final report must 
be submitted within 30 days following the resolution of any comments on 
the draft report.

Negligible Impact Analysis and Determination

    NMFS has defined negligible impact 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 (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of

[[Page 5632]]

recruitment or survival (i.e., population-level effects). An estimate 
of the number of 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 harassment, 
NMFS considers other factors, such as the likely nature of any 
responses (e.g., intensity, duration), the context of any responses 
(e.g., critical reproductive time or location, migration), as well as 
effects on habitat, and the likely effectiveness of the mitigation. We 
also assess the number, intensity, and context of estimated takes by 
evaluating this information relative to population status. Consistent 
with the 1989 preamble for NMFS's implementing regulations (54 FR 
40338; September 29, 1989), the impacts from other past and ongoing 
anthropogenic activities are incorporated into this analysis via their 
impacts on the environmental baseline (e.g., as reflected in the 
regulatory status of the species, population size and growth rate where 
known, ongoing sources of human-caused mortality, or ambient noise 
levels).
    To avoid repetition, our analysis applies to all the species listed 
in Table 1, given that NMFS expects the anticipated effects of the 
proposed seismic survey to be similar in nature. Where there are 
meaningful differences between species or stocks, or groups of species, 
in anticipated individual responses to activities, impact of expected 
take on the population due to differences in population status, or 
impacts on habitat, NMFS has identified species-specific factors to 
inform the analysis.
    NMFS does not anticipate that Level A harassment, serious injury or 
mortality will occur as a result of NSF's proposed seismic survey, even 
in the absence of proposed mitigation. Thus, the proposed authorization 
does not authorize any such takes. As discussed in the Potential 
Effects of Specified Activities on Marine Mammals and their Habitat 
section in our notice of proposed IHA (84 FR 69950), non-auditory 
physical effects, stranding, and vessel strike are not expected to 
occur.
    No takes by Level A harassment are expected or authorized. As 
described above, we expect that marine mammals will be likely to move 
away from a sound source that represents an aversive stimulus, 
especially at levels that will be expected to result in PTS, given 
sufficient notice of the Palmer's approach due to the vessel's 
relatively low speed when conducting seismic surveys. The 100-m 
exclusion zone encompasses the Level A harassment isopleths for all 
marine mammal hearing groups, and is expected to prevent animals from 
being exposed to sound levels that will cause PTS. We expect that any 
instances of take will be in the form of short-term Level B behavioral 
harassment in the form of temporary avoidance of the area or decreased 
foraging (if such activity were occurring), reactions that are 
considered to be of low severity and with no lasting biological 
consequences (e.g., Southall et al., 2007).
    Marine mammal habitat may be impacted by elevated sound levels, but 
these impacts will be temporary. Feeding behavior is not likely to be 
significantly impacted, as marine mammals appear to be less likely to 
exhibit behavioral reactions or avoidance responses while engaged in 
feeding activities (Richardson et al., 1995). Prey species are mobile 
and are broadly distributed throughout the project area; therefore, 
marine mammals that may be temporarily displaced during survey 
activities are expected to be able to resume foraging once they have 
moved away from areas with disturbing levels of underwater noise. 
Because of the temporary nature of the disturbance, the availability of 
similar habitat and resources in the surrounding area, and the lack of 
important or unique marine mammal habitat, the impacts to marine 
mammals and the food sources that they utilize are not expected to 
cause significant or long-term consequences for individual marine 
mammals or their populations. In addition, there are no feeding, mating 
or calving areas known to be biologically important to marine mammals 
within the proposed project area.
    The activity is expected to impact a very small percentage of all 
marine mammal populations that will be affected by NSF's planned survey 
(less than 13 percent each for all marine mammal populations combined). 
Additionally, the acoustic ``footprint'' of the planned survey will be 
very small relative to the ranges of all marine mammal species that 
will potentially be affected. Sound levels will increase in the marine 
environment in a relatively small area surrounding the vessel compared 
to the range of the marine mammals within the planned survey area. This 
includes the small amount of icebreaking, hours at most, expected. The 
effects of icebreaking are transitory, localized, and constrained to a 
relatively narrow swath to each side of the vessel. The seismic array 
will be active 24 hours per day throughout the duration of the proposed 
survey. However, the very brief overall duration of the planned survey 
(eight days) will further limit potential impacts that may occur as a 
result of the proposed activity.
    The planned mitigation measures are expected to reduce the number 
and/or severity of takes by allowing for detection of marine mammals in 
the vicinity of the vessel by visual observers, and by minimizing the 
severity of any potential exposures via shutdowns of the airgun array. 
Based on previous monitoring reports for substantially similar 
activities that have been previously authorized by NMFS, we expect that 
the required mitigation will be effective in minimizing impacts.
    Of the marine mammal species under our jurisdiction that are likely 
to occur in the project area, the following species are listed as 
endangered under the ESA: blue, fin, sei, and sperm whales. Given the 
very low numbers of takes for these species (Table 9), relative to 
their population sizes, as well as the type of take (Level B 
harassment) we do not expect population-level impacts to any of these 
species. The other marine mammal species that may be taken by 
harassment during NSF's seismic survey and icebreaking activities are 
not listed as threatened or endangered under the ESA. There is no 
designated critical habitat for any ESA-listed marine mammals within 
the project area; of the non-listed marine mammals for which we 
authorize take, none are considered ``depleted'' by NMFS under the 
MMPA.
    NMFS concludes that exposures to marine mammal species due to NSF's 
planned seismic survey will result in only short-term (temporary and 
short in duration) effects to individuals exposed, or some small degree 
of PTS to a very small number of individuals. Marine mammals may 
temporarily avoid the immediate area, but are not expected to 
permanently abandon the area. Major shifts in habitat use, 
distribution, or foraging success are not expected. NMFS does not 
anticipate the authorized take estimates to impact annual rates of 
recruitment or survival.
    In summary and as described above, the following factors primarily 
support our determination that the impacts resulting from this activity 
are not expected to adversely affect the species or stock through 
effects on annual rates of recruitment or survival:
     No mortality or serious injury is anticipated or 
authorized;
     No take by Level A harassment is anticipated or 
authorized;
     The anticipated impacts of the proposed activity on marine 
mammals will primarily be temporary behavioral changes of small 
percentages of the affected species due to avoidance of the area around 
the survey vessel. The

[[Page 5633]]

relatively short duration of the proposed survey (10 days; eight days 
of survey plus two contingency days) will further limit the potential 
impacts of any temporary behavioral changes that will occur;
     The availability of alternate areas of similar habitat 
value for marine mammals to temporarily vacate the survey area during 
the proposed survey to avoid exposure to sounds from the activity;
     The proposed project area does not contain areas of 
significance for feeding, mating or calving;
     The potential adverse effects on fish or invertebrate 
species that serve as prey species for marine mammals from the proposed 
survey will be temporary and spatially limited; and
     The planned mitigation measures, including visual and 
acoustic monitoring and shutdowns, are expected to minimize potential 
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 
the proposed activity will have a negligible impact on all affected 
marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    Marine mammals in the survey area are not assigned to NMFS stocks. 
For purposes of the small numbers analysis, we rely on the best 
available information on the abundance estimates for the species of 
marine mammals that could be taken. The numbers of marine mammals that 
we authorize to be taken will be considered small relative to the 
relevant populations (less than 13 percent for all species).
    Based on the analysis contained herein of the planned activity 
(including the required mitigation and monitoring measures) and the 
authorized take of marine mammals, NMFS concludes that small numbers of 
marine mammals will be taken relative to the population sizes of the 
affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. 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.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations with 
no anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that will preclude this categorical 
exclusion. Accordingly, NMFS has determined that the issuance of the 
IHA qualifies to be categorically excluded from further NEPA review.

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure ESA compliance for the issuance of IHAs, 
NMFS consults internally, in this case with the ESA Interagency 
Cooperation Division, whenever we propose to authorize take for 
endangered or threatened species.
    The NMFS Office of Protected Resources Interagency Cooperation 
Division issued a Biological Opinion on January 23, 2020, under section 
7 of the ESA, on the issuance of an IHA to NSF under section 
101(a)(5)(D) of the MMPA by the NMFS Office of Protected Resources 
Permits and Conservation Division. The Biological Opinion concluded 
that the proposed action is not likely to jeopardize the continued 
existence of blue, fin, sei, and sperm whales, and is not likely to 
destroy or modify critical habitat of listed species because no 
critical habitat exists for these species in the action area.

Authorization

    As a result of these determinations, NMFS has issued an IHA to NSF 
for conducting the specified activity in the Amundsen Sea, provided the 
previously mentioned mitigation, monitoring, and reporting requirements 
are incorporated.

    Dated: January 27, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-01811 Filed 1-30-20; 8:45 am]
 BILLING CODE 3510-22-P