[Federal Register Volume 85, Number 122 (Wednesday, June 24, 2020)]
[Notices]
[Pages 37848-37874]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-13605]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XR101]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Marine Site Characterization 
Surveys off of Massachusetts, Rhode Island, Connecticut, New York and 
New Jersey

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from Equinor Wind, LLC (Equinor) 
for authorization to take marine mammals incidental to marine site 
characterization surveys in the Atlantic Ocean in the area of the 
Commercial Leases of Submerged Lands for Renewable Energy Development 
on the Outer Continental Shelf (OCS-A 0520 and OCS-A 0512) and along 
potential submarine cable routes to a landfall location in 
Massachusetts, Rhode Island, Connecticut, New York or New Jersey. 
Pursuant to the Marine Mammal Protection Act (MMPA), NMFS is requesting 
comments on its proposal to issue an incidental harassment 
authorization (IHA) to incidentally take marine mammals during the 
specified activities. NMFS is also requesting comments on a possible 
one-year renewal that could be issued under certain circumstances and 
if all requirements are met, as described in Request for Public 
Comments at the end of this notice. NMFS will consider public comments 
prior to making any final decision on the issuance of the requested 
MMPA authorizations and agency responses will be summarized in the 
final notice of our decision.

DATES: Comments and information must be received no later than July 24, 
2020.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Physical comments should be sent to 
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments 
should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. All comments received are a part of the 
public record and will generally be posted online at 
www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable without change. 
All personal identifying information (e.g., name, address) voluntarily 
submitted by the commenter may be publicly accessible. Do not submit 
confidential business information or otherwise sensitive or protected 
information.

FOR FURTHER INFORMATION CONTACT: Rob Pauline, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the applications 
and

[[Page 37849]]

supporting documents, as well as a list of the references cited in this 
document, may be obtained by visiting the internet at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable. 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 such 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 such takings are set forth.
    The definitions of all applicable MMPA statutory terms cited above 
are included in the relevant sections below.

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 evaluate our proposed action (i.e., the promulgation of 
regulations and subsequent issuance of incidental take authorization) 
and alternatives with respect to potential impacts on the human 
environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 of the Companion Manual for NAO 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 would 
preclude this categorical exclusion. Accordingly, NMFS has 
preliminarily determined that the proposed action qualifies to be 
categorically excluded from further NEPA review.
    Information in Equinor's application and this notice collectively 
provide the environmental information related to proposed issuance of 
these regulations and subsequent incidental take authorization for 
public review and comment. We will review all comments submitted in 
response to this notice prior to concluding our NEPA process or making 
a final decision on the request for incidental take authorization.

Summary of Request

    On January 30, 2020, NMFS received a request from Equinor for an 
IHA to take marine mammals incidental to marine site characterization 
surveys in the Atlantic Ocean in the area of the Commercial Leases of 
Submerged Lands for Renewable Energy Development on the Outer 
Continental Shelf (OCS-A 0520 and OCS-A 0512) and along potential 
submarine cable routes to a landfall location in Massachusetts, Rhode 
Island, Connecticut, New York or New Jersey. A revised application was 
received on March 31, 2020. NMFS deemed that request to be adequate and 
complete. On May 22, Equinor notified NMFS of a revision to their 
proposed activities and submitted a revised IHA application reflecting 
the change. Equinor's request is for the take of 17 marine mammal 
stocks, by Level B harassment only. Neither Equinor nor NMFS expects 
serious injury or mortality to result from this activity and the 
activity is expected to last no more than one year, therefore, an IHA 
is appropriate.

Description of the Proposed Activity

Overview

    Equinor proposes to conduct marine site characterization surveys, 
including high-resolution geophysical (HRG) and geotechnical surveys, 
in the area of Commercial Leases of Submerged Lands for Renewable 
Energy Development on the Outer Continental Shelf #OCS-A 0520 and #OCS-
A 0512 (Lease Areas) and along potential submarine cable routes 
offshore Massachusetts, Rhode Island, Connecticut, New York and New 
Jersey.
    The purpose of the proposed surveys is to support the preliminary 
site characterization, siting, and engineering design of offshore wind 
project facilities including wind turbine generators, offshore 
substations, and submarine cables within the Lease Areas and in export 
cable route areas (ECRAs). As many as two survey vessels may operate 
concurrently as part of the proposed surveys. Underwater sound 
resulting from Equinor's proposed surveys has the potential to result 
in the incidental take of marine mammals in the form of behavioral 
harassment.

Dates and Duration

    The estimated duration of the HRG surveys is expected to be up to 
218 total days over the course of one year. Geotechnical sampling is 
anticipated to occur for a total of 135 days over the course of one 
year. This schedule is based on 24-hour operations and includes 
potential down time due to inclement weather.

Specific Geographic Region

    Equinor's survey activities would occur in the Northwest Atlantic 
Ocean within Federal and state waters. Surveys would occur in the Lease 
Areas and in ECRAs offshore Massachusetts, Rhode Island, Connecticut, 
New York and New Jersey (see Figure 1-1 in the IHA application).

Detailed Description of the Specified Activities

    Equinor's proposed marine site characterization surveys include HRG 
and geotechnical survey activities. These survey activities would occur 
within the Lease Areas and within ECRAs between the Lease Areas and the 
coasts of Massachusetts, Rhode Island, Connecticut, New York and New 
Jersey. For the purpose of this IHA the Lease Areas and ECRAs are 
collectively referred to as the Project Area.
    Geophysical and shallow geotechnical survey activities are 
anticipated to be supported by vessels which will maintain a speed of 
approximately 4 knots (kn) while transiting survey lines. The proposed 
HRG and geotechnical survey activities are described below.

Geotechnical Survey Activities

    Equinor's proposed geotechnical survey activities would include the 
following:
     Sample boreholes to determine geological and geotechnical 
characteristics of sediments;
     Deep cone penetration tests (CPTs) to determine 
stratigraphy and in situ conditions of the deep surface sediments; and

[[Page 37850]]

     Vibracores to determine the geological and geotechnical 
characteristics of the sediments.
    Geotechnical investigation activities are anticipated to be 
conducted from a drill ship equipped with dynamic positioning (DP) 
thrusters. It is anticipated that vibracore samples, borings and CPT 
may be obtained at each planned wind turbine location in the Lease 
Areas. Impact to the seafloor from this equipment will be limited to 
the minimal contact of the sampling equipment, and inserted boring and 
probes.
    In considering whether marine mammal harassment is an expected 
outcome of exposure to a particular activity or sound source, NMFS 
considers the nature of the exposure itself (e.g., the magnitude, 
frequency, or duration of exposure), characteristics of the marine 
mammals potentially exposed, and the conditions specific to the 
geographic area where the activity is expected to occur (e.g., whether 
the activity is planned in a foraging area, breeding area, nursery or 
pupping area, or other biologically important area for the species). We 
then consider the expected response of the exposed animal and whether 
the nature and duration or intensity of that response is expected to 
cause disruption of behavioral patterns (e.g., migration, breathing, 
nursing, breeding, feeding, or sheltering) or injury.
    Geotechnical survey activities would be conducted from a drill ship 
equipped with DP thrusters. DP thrusters would be used to position the 
sampling vessel on station and maintain position at each sampling 
location during the sampling activity. Sound produced through use of DP 
thrusters is similar to that produced by transiting vessels and DP 
thrusters are typically operated either in a similarly predictable 
manner or used for short durations around stationary activities. NMFS 
does not believe acoustic impacts from DP thrusters are likely to 
result in take of marine mammals in the absence of activity- or 
location-specific circumstances that may otherwise represent specific 
concerns for marine mammals (i.e., activities proposed in area known to 
be of particular importance for a particular species), or associated 
activities that may increase the potential to result in take when in 
concert with DP thrusters. In this case, we are not aware of any such 
circumstances. Therefore, NMFS believes the likelihood of DP thrusters 
used during the proposed geotechnical surveys resulting in harassment 
of marine mammals to be so low as to be discountable. As DP thrusters 
are not expected to result in take of marine mammals, these activities 
are not analyzed further in this document.
    Field studies conducted off the coast of Virginia to determine the 
underwater noise produced by CPTs and borehole drilling found that 
these activities did not result in underwater noise levels that 
exceeded current thresholds for Level B harassment of marine mammals 
(Kalapinski, 2015). Given the small size and energy footprint of 
geotechnical survey activities, NMFS believes the likelihood that noise 
from these activities would exceed the Level B harassment threshold at 
any appreciable distance is so low as to be discountable. Therefore, 
geotechnical survey activities are not expected to result in harassment 
of marine mammals and are not analyzed further in this document.

Geophysical Survey Activities

    Equinor has proposed that HRG survey operations would be conducted 
continuously 24 hours per day. Based on 24-hour operations, the 
estimated total duration of the proposed activities would be 
approximately 218 survey days (Table 1). These estimated durations 
include estimated weather down time.

            Table 1--Summary of Proposed HRG Survey Segments
------------------------------------------------------------------------
                                                             Duration
                     Survey segment                        (survey days)
------------------------------------------------------------------------
ECRA 1..................................................           11.25
ECRA 2..................................................           70.25
ECRA 3..................................................           11.25
ECRA 4..................................................          125.25
All survey areas combined...............................             218
------------------------------------------------------------------------

    Equinor's HRG survey activities would be supported by a maximum of 
two concurrently-operating source vessels. HRG equipment on the survey 
vessel would either be mounted to or towed behind the survey vessel. 
Vessels would operate at a typical survey speed of approximately 4 
knots (7.4 km per hour) while surveying. Surveys within the Lease Areas 
would be conducted along tracklines spaced a minimum of 30 meters (m) 
(98 feet (ft)) apart. Up to two cable route corridors within the ECRAs 
(Figure 1-1 in the IHA application) would be surveyed along tracklines 
that would also be spaced a minimum of 30 m (98 ft) apart. The full 
survey protocol is designed to meet BOEM requirements as defined in the 
July 2015 ``Guidelines for Providing Geophysical, Geotechnical, and 
Geohazard Information Pursuant to 30 CFR part 585'' and the March 2017 
``Guidelines for Providing Archeological and Historical Property 
Information Pursuant to 30 CFR part 585.''
    Equinor has proposed to deploy some types of HRG equipment on a 
Surveyor Remotely Operated Vehicle (SROV) (see Figure 1-3 in the IHA 
application). The SROV is fully controlled from the surface vessel and 
is equipped with multibeam echosounders, triangulating lasers, and 
video-photo mosaic cameras as well as side scan sonar, a shallow 
penetration sub-bottom profiler, and gradiometer. It is specially 
designed to increase the progress rate during the survey along 
tracklines where medium penetration sub-bottom profiler data is not 
required. SROV operations facilitate better trackline fidelity compared 
to traditional vessel-based survey operations as the SROV is de-coupled 
from the surface motion of the water and is not affected by wind or 
wave action. Equinor estimates that the SROV, which would not exceed 
the speed of the mother ship, has the potential to increase survey 
efficiency by 25 percent over vessel-based surveys due to an ability to 
survey with quicker line turns, resulting in fewer re-runs of 
tracklines. The SROV also minimizes limitations on surveys that may 
otherwise result from adverse weather conditions. The SROV would 
maintain a depth of no higher than 6 m above the seabed at all times 
while actively surveying, in accordance with BOEM guidelines for 
acceptable operation of a gradiometer.
    The geophysical survey activities proposed by Equinor would include 
the following:
     Shallow Penetration sub-bottom profilers (SBP) (Pinger/
CHIRP/Parametric) to map near-surface stratigraphy (0 to 5 m (0 to 16 
ft) of sediment below the seabed). SBP emit sonar pulses that increase 
in frequency (3.5 to 200 kiloHertz (kHz)) over time. The pulse length 
frequency range can be adjusted depending on project needs. The shallow 
penetration SBPs are only operated from the SROV.
     Medium Penetration SBPs (Sparker/Boomer) to map deeper 
subsurface stratigraphy as needed. A medium SBP system emits acoustic 
pulses from 50 kHz to 4 kHz, omnidirectional from the source that can 
penetrate hundreds of meters into the seafloor. Medium penetration SBPs 
are usually towed behind the vessel with adjacent hydrophone arrays to 
detect the return signals.
     Ultra-Short Baseline (USBL) Positioning and Global 
Acoustic Positioning System (GAPS) to provide high accuracy ranges by 
measuring the time between the acoustic pulses transmitted by the 
vessel transceiver and the equipment necessary to produce the acoustic 
profile. USBL/GAPS are

[[Page 37851]]

two-component systems usually with a hull or side pole mounted 
transceiver and one or more transponders on the seabed or the 
equipment.
     Single and Multibeam Depth Sounders to determine water 
depths and general topography. The multibeam echosounder sonar system 
projects sonar pulses in several angled beams from a transducer mounted 
to SROV. The beams radiate out from the transducer in a fan-shaped 
pattern orthogonally to the ship's direction. This equipment would only 
be operated from the SROV and operates above 180 kHz (outside the 
functional hearing ranges of all marine mammals).
     Side scan sonar (SSS) for seabed sediment classification 
purposes and to identify man-made acoustic targets on the seafloor. 
This sonar device emits conical or fan-shaped pulses down toward the 
seafloor in multiple beams at a wide angle, perpendicular to the path 
of the sensor through the water. The acoustic return of the pulses can 
be joined to form an image of the sea bottom within the swath of the 
beam. SSSs are typically towed behind the vessel or mounted to the 
hull. The SSS would only be operated from the SROV and operates above 
180 kHz (outside the functional hearing ranges of all marine mammals).
     Sound Velocity Profiler to measure speed of sound to make 
corrections for calibration of equipment. Sound Velocity Profilers 
operate above 180 kHz (outside the functional hearing ranges of all 
marine mammals).
     Marine Gradiometer (magnetometer) to detect and map 
ferrous objects on and below the seafloor which may cause a hazard, 
including anchors, chains, cables, scattered shipwreck debris, 
unexploded ordnances, aircraft, and any other objects with a magnetic 
expression. Note that the magnetometer is not a sound source.
    The deployment of HRG survey equipment, including some of the 
equipment planned for use during Equinor's proposed activity, produces 
sound in the marine environment that has the potential to result in 
harassment of marine mammals. However, sound propagation of HRG sources 
is dependent on several factors including operating mode, frequency, 
depth of source and beam direction of the equipment; thus, potential 
impacts to marine mammals from HRG equipment are driven by the 
specification of individual HRG sources. The specifications of the 
potential equipment planned for use during HRG survey activities (Table 
1-1 in the IHA application) were analyzed to determine which types of 
equipment would have the potential to result in harassment of marine 
mammals. Based on the best available information, the likelihood of HRG 
equipment that operates either at frequency ranges that fall outside 
the functional hearing ranges of marine mammals (e.g., above 180 kHz) 
or within marine mammal functional hearing ranges but with low sound 
source levels (e.g., a single pulse at less than 200 decibel (dB) re re 
1 micro-Pascal ([mu]Pa)) to result in the take of marine mammals is so 
low as to be discountable. These equipment types were therefore 
eliminated from further analysis. As noted above, these include: The 
multibeam echosounder, Sound Velocity Profiler, and SSS. As we have 
determined these sources will not result in the take of marine mammals, 
they are not analyzed further in this document. In addition, the Marine 
Gradiometer (magnetometer) is not a sound source and therefore does not 
have the potential to result in take of marine mammals, and is 
therefore not analyzed further in this document. As described above, 
the SROV would maintain a depth of no higher than 6 m above the seabed 
at all times while actively surveying. Thus, a marine mammal would have 
to pass between the SROV and the seabed and through the beam of the HRG 
source in order to be exposed to noise from HRG equipment operating 
from the SROV. As the SROV would never operate more than 6 m above the 
seabed while operating active HRG equipment, this is extremely unlikely 
to occur. In addition, the shallow penetration SBP that is operated 
from the SROV has a narrow beam (maximum of 36 degrees). Therefore, 
NMFS has determined the potential for take of marine mammals as a 
result of exposure to HRG equipment operated from the SROV is so low as 
to be discountable, and HRG equipment operated from the SROV is not 
analyzed further in this document.
    Table 2 identifies the representative survey equipment that may be 
used in support of proposed vessel-based geophysical survey activities 
that has the potential to result in the take of marine mammals. As 
described above, HRG equipment operated from the SROV but not the 
vessel are not expected to result in the incidental take of marine 
mammals and are therefore not shown in Table 2 (all HRG equipment types 
proposed for use by Equinor, including those operated from the SROV, 
are shown in Table 1-1 of the IHA application). Geophysical surveys are 
expected to use multiple equipment types concurrently in order to 
collect multiple aspects of geophysical data along one transect.

      Table 2--Summary of Vessel-Based HRG Survey Equipment Proposed for Use by Equinor With the Potential To Result in the Take of Marine Mammals
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                                                                                                             Pulse
                                                                                SL rms  (dB   SL pk  (dB    duration    Repetition       Beam width
        HRG equipment type                Equipment        Operating frequency  re 1 [mu]Pa  re 1 [mu]Pa    (milli-     rate  (Hz)        (degrees)
                                                                                     m)           m)        second)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Subsea Positioning/USBL \1\.......  Kongsberg HiPAP 501/  21-31...............          190          207            2            1  15.
                                     502.
Medium Sub-bottom Profiler \2\....  Geo-Source 400 Tip    0.25 to 3.25........          203          213            2            4  Omni-directional.
                                     Sparker Source.
                                    (800 J).............
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\1\ Sound source characteristics from manufacturer specifications.
\2\ SLs as reported for the ELC820 sparker in Crocker and Fratantonio (2016) which represents the most applicable proxy to the Geo-Source 800-J sparker
  expected for use during Equinor's proposed surveys.

    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activity

    Sections 3 and 4 of the IHA application summarize available

[[Page 37852]]

information regarding status and trends, distribution and habitat 
preferences, and behavior and life history, of the potentially affected 
species. Additional information regarding population trends and threats 
may be found in NMFS' Stock Assessment Reports (SARs; 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS' 
website (www.fisheries.noaa.gov/find-species). All species that could 
potentially occur in the proposed survey areas are included in Table 4-
1 of the IHA application. However, the temporal and/or spatial 
occurrence of several species listed in Table 7-2 of the IHA 
application is such that take of these species is not expected to occur 
either because they have very low densities in the project area or are 
known to occur further offshore than the project area. These are: The 
blue whale (Balaenoptera musculus), Bryde's whale (Balaenoptera edeni), 
Cuvier's beaked whale (Ziphius cavirostris), four species of 
Mesoplodont beaked whale (Mesoplodon spp.), dwarf and pygmy sperm whale 
(Kogia sima and Kogia breviceps), short-finned pilot whale 
(Globicephala macrorhynchus), northern bottlenose whale (Hyperoodon 
ampullatus), killer whale (Orcinus orca), pygmy killer whale (Feresa 
attenuata), false killer whale (Pseudorca crassidens), melon-headed 
whale (Peponocephala electra), striped dolphin (Stenella coeruleoalba), 
white-beaked dolphin (Lagenorhynchus albirostris), pantropical spotted 
dolphin (Stenella attenuata), Fraser's dolphin (Lagenodelphis hosei), 
rough-toothed dolphin (Steno bredanensis), Clymene dolphin (Stenella 
clymene), spinner dolphin (Stenella longirostris), and hooded seal 
(Cystophora cristata). As take of these species is not anticipated as a 
result of the proposed activities, these species are not analyzed 
further.
    Table 3 summarizes information related to the population or stock, 
including regulatory status under the MMPA and Endangered Species Act 
(ESA) and potential biological removal (PBR), where known. For 
taxonomy, we follow Committee on Taxonomy (2019). PBR is 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 (as described in NMFS' SARs). While no mortality is 
anticipated or authorized here, PBR is included here as a gross 
indicator of the status of the species and other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS' stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS' U.S. Atlantic SARs. All values presented in Table 3 are the most 
recent available at the time of publication and are available in the 
2019 draft Atlantic SARs (Hayes et al., 2019), available online at: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports-region.

                      Table 3--Marine Mammals Known to Occur in the Survey Area That May Be Affected by Equinor's Proposed Activity
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         Stock abundance
                                                        MMPA and ESA     (CV, Nmin, most      Predicted
  Common Name (scientific name)          Stock             status;      recent  abundance     abundance     PBR \4\   Annual M/   Occurrence in  project
                                                        strategic (Y/      survey) \2\        (CV) \3\                  SI \4\             area
                                                           N) \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Toothed whales (Odontoceti)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter             North Atlantic.....  E; Y            4,349 (0.28;          5,353 (0.12)        6.9        0.0  Rare.
 macrocephalus).                                                        3,451; n/a).
Atlantic white-sided dolphin      W. North Atlantic..  -; N            93,233 (0.71;        37,180 (0.07)        544         26  Common.
 (Lagenorhynchus acutus).                                               54,443; n/a).
Atlantic spotted dolphin          W. North Atlantic..  -; N            39,921 (0.27;        55,436 (0.32)        320          0  Common.
 (Stenella frontalis).                                                  32,032; 2012).
Common dolphin (Delphinus         W. North Atlantic..  -; N            172,825 (0.21;       86,098 (0.12)      1,452        419  Common.
 delphis).                                                              145,216; 2011).
Bottlenose dolphin (Tursiops      W. North Atlantic,   -; N            62,851 (0.23;           \5\ 97,476        519         28  Common offshore.
 truncatus).                       Offshore.                            51,914; 2011).             (0.06)
                                  W. North Atlantic,   -; N            6,639 (0.41;        ..............         48   6.1-13.2  Common nearshore.
                                   Northern Coastal                     4,759; 2015).
                                   Migratory.
Long-finned pilot whale           W. North Atlantic..  -; N            39,215 (0.3;            \5\ 18,977        306         21  Rare.
 (Globicephala melas).                                                  30,627; n/a).              (0.11)
Risso's dolphin (Grampus          W. North Atlantic..  -; N            35,493 (0.19;         7,732 (0.09)        303       54.3  Rare.
 griseus).                                                              30,289; 2011).
Harbor porpoise (Phocoena         Gulf of Maine/Bay    -; N            95,543 (0.31;             * 45,089        851        217  Common.
 phocoena).                        of Fundy.                            74,034; 2011).             (0.12)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Baleen whales (Mysticeti)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fin whale (Balaenoptera           W. North Atlantic..  E; Y            7,418 (0.25;          4,633 (0.08)         12       2.35  Year round in
 physalus).                                                             6,025; n/a).                                              continental shelf and
                                                                                                                                  slope waters.
Sei whale (Balaenoptera           Nova Scotia........  E; Y            6,292 (1.015;         * 717 (0.30)        6.2        1.0  Year round in
 borealis).                                                             3,098; n/a).                                              continental shelf and
                                                                                                                                  slope waters.
Minke whale (Balaenoptera         Canadian East Coast  -; N            24,202 (0.3;        * 2,112 (0.05)        8.0        7.0  Year round in
 acutorostrata).                                                        18,902; n/a).                                             continental shelf and
                                                                                                                                  slope waters.
Humpback whale (Megaptera         Gulf of Maine......  -; N            1,396 (0; 1,380; n/ * 1,637 (0.07)         22      12.15  Common year round.
 novaeangliae).                                                         a).

[[Page 37853]]

 
North Atlantic right whale        W. North Atlantic..  E; Y            428 (0; 418; n/a).    * 535 (0.45)        0.8       6.85  Occur seasonally.
 (Eubalaena glacialis).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                Earless seals (Phocidae)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray seal \6\ (Halichoerus        W. North Atlantic..  -; N            27,131 (0.19;                  n/a      1,389      5,410  Common.
 grypus).                                                               23,158; n/a).
Harbor seal (Phoca vitulina)....  W. North Atlantic..  -; N            75,834 (0.15;                  n/a      2,006        350  Common.
                                                                        66,884; 2012).
Harp seal \7\ (Pagophilus         W. North Atlantic..  -; N            Unknown (n/a; n/a;             n/a       unk.    232,422  Rare.
 groenlandicus).                                                        n/a).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ 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 (see
  footnote 3) 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.
\2\ Stock abundance as reported in NMFS marine mammal stock assessment reports (SAR) except where otherwise noted. SARs available online at:
  www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments. CV is coefficient of variation; Nmin is the minimum estimate
  of stock abundance. In some cases, CV is not applicable. For certain stocks, abundance estimates are actual counts of animals and there is no
  associated CV. The most recent abundance survey that is reflected in the abundance estimate is presented; there may be more recent surveys that have
  not yet been incorporated into the estimate. All values presented here are from the 2019 draft Atlantic SARs (Hayes et al., 2019).
\3\ This information represents species- or guild-specific abundance predicted by recent habitat-based cetacean density models (Roberts et al., 2016,
  2017, 2018). These models provide the best available scientific information regarding predicted density patterns of cetaceans in the U.S. Atlantic
  Ocean, and we provide the corresponding abundance predictions as a point of reference. Total abundance estimates were produced by computing the mean
  density of all pixels in the modeled area and multiplying by its area. For those species marked with an asterisk, the available information supported
  development of either two or four seasonal models; each model has an associated abundance prediction. Here, we report the maximum predicted abundance.
\4\ Potential biological removal, 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 size (OSP). Annual M/SI, found in NMFS' SARs,
  represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial fisheries, subsistence hunting, ship
  strike). Annual M/SI values often cannot be determined precisely and is in some cases presented as a minimum value. All M/SI values are as presented
  in the draft 2019 SARs (Hayes et al., 2019).
\5\ Abundance estimates are in some cases reported for a guild or group of species when those species are difficult to differentiate at sea. Similarly,
  the habitat-based cetacean density models produced by Roberts et al. (2016, 2017, 2018) are based in part on available observational data which, in
  some cases, is limited to genus or guild in terms of taxonomic definition. Roberts et al. (2016, 2017, 2018) produced density models to genus level
  for Globicephala spp. and produced a density model for bottlenose dolphins that does not differentiate between offshore and coastal stocks.
\6\ NMFS stock abundance estimate applies to U.S. population only, actual stock abundance is approximately 505,000.
\7\ Stock abundance estimate is not available in NMFS SARs and predicted abundance estimate is not provided in Roberts et al. (2016, 2017, 2018).

    Four marine mammal species that are listed under the ESA may be 
present in the survey area and are included in the take request: the 
North Atlantic right, fin, sei, and sperm whale.
    Below is a description of the species that have the highest 
likelihood of occurring in the project area and are thus expected to 
potentially be taken by the proposed activities. For the majority of 
species potentially present in the specific geographic region, NMFS has 
designated only a single generic stock (e.g., ``western North 
Atlantic'') for management purposes. This includes the ``Canadian east 
coast'' stock of minke whales, which includes all minke whales found in 
U.S. waters, and is also a generic stock for management purposes. For 
humpback whales, NMFS defines stocks on the basis of feeding locations 
(i.e., Gulf of Maine). However, references to humpback whales in this 
document refer to any individuals of the species that are found in the 
specific geographic region.

North Atlantic Right Whale

    The North Atlantic right whale ranges from calving grounds in the 
southeastern United States to feeding grounds in New England waters and 
into Canadian waters (Hayes et al., 2018). Surveys have demonstrated 
the existence of seven areas where North Atlantic right whales 
congregate seasonally, including in Georges Bank, off Cape Cod, and in 
Massachusetts Bay (Hayes et al., 2018). In the late fall months (e.g. 
October), right whales are generally thought to depart from the feeding 
grounds in the North Atlantic and move south to their calving grounds 
off Georgia and Florida. However, recent research indicates our 
understanding of their movement patterns remains incomplete (Davis et 
al., 2017). A review of passive acoustic monitoring data from 2004 to 
2014 throughout the western North Atlantic demonstrated nearly 
continuous year-round right whale presence across their entire habitat 
range (for at least some individuals), including in locations 
previously thought of as migratory corridors, suggesting that not all 
of the population undergoes a consistent annual migration (Davis et 
al., 2017).
    Aerial surveys indicate that right whales are consistently detected 
within and near Lease Area 0520 and surrounding survey areas, 
particularly ECRA-1 and the eastern portion of ECRA-2 (see Figure 4-1 
in the IHA application), during winter and early spring. It appears 
that right whales begin to arrive in this area in December and remain 
in the area through at least April. Acoustic detections of right whales 
within the MA and RI/MA Wind Energy Areas (WEAs), which include the 
proposed survey areas, were documented during all months of the year, 
although the highest number of detections between December and late May 
(Kraus et al. 2016). Aerial survey data indicate that right whales 
occur at elevated densities in the survey areas south and southwest of 
Martha's Vineyard and Nantucket, and in Cape Cod Bay, between December 
and May (Roberts et al. 2018; Leiter et al. 2017; Kraus et al. 2016).
    The western North Atlantic right whale population demonstrated 
overall growth of 2.8 percent per year between 1990 to 2010, despite a 
decline in 1993 and no growth between 1997 and 2000 (Pace et al. 2017). 
However, since 2010 the population has been in decline, with a 99.99 
percent probability of a decline of just under 1 percent per year (Pace 
et al., 2017). Between 1990 and 2015, calving rates varied 
substantially, with low calving rates coinciding with all three periods 
of decline or no growth (Pace et al., 2017). On average, North Atlantic 
right whale calving rates are estimated to be roughly half that of 
southern right whales (Eubalaena australis) (Pace et al., 2017), which 
are increasing in abundance (NMFS, 2015).

[[Page 37854]]

In 2018, no new North Atlantic right whale calves were documented in 
their calving grounds, representing the first time since annual NOAA 
aerial surveys began in 1989 that no new right whale calves were 
observed. Seven right whale calves were documented in 2019 and ten 
right whale calves were observed in 2020. The current best estimate of 
population abundance for the species is 409 individuals, based on data 
as of September, 2019 (Pettis et al., 2019).
    Elevated North Atlantic right whale mortalities have occurred since 
June 7, 2017 along the U.S. and Canadian coast. As of June, 2020, a 
total of 30 confirmed dead stranded whales (21 in Canada; 9 in the 
United States) have been documented. This event has been declared an 
Unusual Mortality Event (UME), with human interactions, including 
entanglement in fixed fishing gear and vessel strikes, implicated in at 
least 15 of the mortalities thus far. More information is available 
online at: www.fisheries.noaa.gov/national/marine-life-distress/2017-2019-north-atlantic-right-whale-unusual-mortality-event.
    The proposed survey areas are part of a biologically important 
migratory area for North Atlantic right whales; this important 
migratory area is comprised of the waters of the continental shelf 
offshore the East Coast of the United States and extends from Florida 
through Massachusetts. NMFS' regulations at 50 CFR part 224.105 
designated nearshore waters of the Mid-Atlantic Bight as Mid-Atlantic 
U.S. Seasonal Management Areas (SMA) for right whales in 2008. SMAs 
were developed to reduce the threat of collisions between ships and 
right whales around their migratory route and calving grounds. Within 
SMAs, the regulations require a mandatory vessel speed (less than 10 
knots) for all vessels greater than 65 ft. Five SMAs overlap spatially, 
either fully or partially, with the proposed survey areas. These 
include: the Off Race Point SMA (in effect from January 1 through May 
15); the Cape Cod Bay SMA (in effect from March 1 through April 30); 
the Great South Channel SMA (in effect from April 1 through July 31); 
the Block Island Sound SMA (in effect from November 1 through April 
30); and the New York/New Jersey SMA (in effect from November 1 through 
April 30).
    NMFS has designated two critical habitat areas for the North 
Atlantic right whale under the ESA: The Gulf of Maine/Georges Bank 
region, and the southeast calving grounds from North Carolina to 
Florida. Portions of the proposed survey areas overlap spatially with 
the Gulf of Maine/Georges Bank critical habitat which was established 
due to the area's significance for right whale foraging (81 FR 4837, 
January 27, 2016). The rulemaking establishing critical habitat in the 
Gulf of Maine/Georges Bank region that partially overlaps the proposed 
survey area identified that area as particularly suitable to 
aggregations of Calanus finmarchicus (a species of copepod that is a 
preferred prey of the North Atlantic right whale) and recognized that 
features of habitat in the area were deemed essential to the 
conservation of the species (81 FR 4837, January 27, 2016). Measures to 
minimize potential impacts to North Atlantic right whales within SMAs 
and designated critical habitat are described under Proposed 
Mitigation.

Humpback Whale

    Humpback whales are found worldwide in all oceans. Humpback whales 
were listed as endangered under the Endangered Species Conservation Act 
(ESCA) in June 1970. In 1973, the ESA replaced the ESCA, and humpback 
whales continued to be listed as endangered. On September 8, 2016, NMFS 
divided the species into 14 distinct population segments (DPS), removed 
the current species-level listing, and in its place listed four DPSs as 
endangered and one DPS as threatened (81 FR 62260; September 8, 2016). 
The remaining nine DPSs were not listed. The West Indies DPS, which is 
not listed under the ESA, is the only DPS of humpback whales that is 
expected to occur in the project area.
    Humpback whales utilize the mid-Atlantic as a migration pathway 
between calving/mating grounds to the south and feeding grounds in the 
north (Waring et al. 2007). A key question with regard to humpback 
whales off the Mid-Atlantic states is their stock identity. Using fluke 
photographs of living and dead whales observed in the region, Barco et 
al. (2002) reported that 43 percent of 21 live whales matched to the 
Gulf of Maine, 19 percent to Newfoundland, and 4.8 percent to the Gulf 
of St Lawrence, while 31.6 percent of 19 dead humpbacks were known Gulf 
of Maine whales. Although the population composition of the mid-
Atlantic is apparently dominated by Gulf of Maine whales, lack of 
photographic effort in Newfoundland makes it likely that the observed 
match rates under-represent the true presence of Canadian whales in the 
region (Waring et al., 2016). Barco et al. (2002) suggested that the 
mid-Atlantic region primarily represents a supplemental winter feeding 
ground used by humpback whales.
    Since January 2016, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine to Florida. As of June, 
2020, partial or full necropsy examinations have been conducted on 
approximately half of the 126 known cases. Of the whales examined, 
about 50 percent had evidence of human interaction, either ship strike 
or entanglement. While a portion of the whales have shown evidence of 
pre-mortem vessel strike, this finding is not consistent across all 
humpback whales examined and more research is needed. NOAA is 
consulting with researchers that are conducting studies on the humpback 
whale populations, and these efforts may provide information on changes 
in whale distribution and habitat use that could provide additional 
insight into how these vessel interactions occurred. Three previous 
UMEs involving humpback whales have occurred since 2000, in 2003, 2005, 
and 2006. More information is available at: www.fisheries.noaa.gov/national/marine-life-distress/2016-2019-humpback-whale-unusual-mortality-event-along-atlantic-coast.

Fin Whale

    Fin whales are common in waters of the U.S. Atlantic Exclusive 
Economic Zone (EEZ), principally from Cape Hatteras northward (Waring 
et al., 2016). Fin whales are present north of 35-degree latitude in 
every season and are broadly distributed throughout the western North 
Atlantic for most of the year (Waring et al., 2016). They are typically 
found in small groups of up to five individuals (Brueggeman et al., 
1987). The main threats to fin whales are fishery interactions and 
vessel collisions (Waring et al., 2016).

Sei Whale

    The Nova Scotia stock of sei whales can be found in deeper waters 
of the continental shelf edge waters of the northeastern U.S. and 
northeastward to south of Newfoundland. The southern portion of the 
stock's range during spring and summer includes the Gulf of Maine and 
Georges Bank. Spring is the period of greatest abundance in U.S. 
waters, with sightings concentrated along the eastern margin of Georges 
Bank and into the Northeast Channel area, and along the southwestern 
edge of Georges Bank in the area of Hydrographer Canyon (Waring et al., 
2015). Sei whales occur in shallower waters to feed. Sei whales are 
listed as endangered under the ESA, and the Nova Scotia stock is 
considered strategic and depleted under the MMPA. The main threats to 
this stock are

[[Page 37855]]

interactions with fisheries and vessel collisions.

Minke Whale

    Minke whales can be found in temperate, tropical, and high-latitude 
waters. The Canadian East Coast stock can be found in the area from the 
western half of the Davis Strait (45[deg] W) to the Gulf of Mexico 
(Waring et al., 2016). This species generally occupies waters less than 
100 m deep on the continental shelf. There appears to be a strong 
seasonal component to minke whale distribution in the survey areas, in 
which spring to fall are times of relatively widespread and common 
occurrence while during winter the species appears to be largely absent 
(Waring et al., 2016). Since January 2017, elevated minke whale 
mortalities have occurred along the Atlantic coast from Maine through 
South Carolina. This event has been declared a UME. As of June, 2020 
partial or full necropsy examinations have been conducted on more than 
60 percent of the 88 known cases. Preliminary findings in several of 
the whales have shown evidence of human interactions or infectious 
disease, but these findings are not consistent across all of the whales 
examined, so more research is needed. More information is available at: 
www.fisheries.noaa.gov/national/marine-life-distress/2017-2019-minke-whale-unusual-mortality-event-along-atlantic-coast.

Sperm Whale

    The distribution of the sperm whale in the U.S. EEZ occurs on the 
continental shelf edge, over the continental slope, and into mid-ocean 
regions (Waring et al., 2014). The basic social unit of the sperm whale 
appears to be the mixed school of adult females plus their calves and 
some juveniles of both sexes, normally numbering 20-40 animals in all. 
There is evidence that some social bonds persist for many years 
(Christal et al., 1998). This species forms stable social groups, site 
fidelity, and latitudinal range limitations in groups of females and 
juveniles (Whitehead, 2002). In summer, the distribution of sperm 
whales includes the area east and north of Georges Bank and into the 
Northeast Channel region, as well as the continental shelf (inshore of 
the 100-m isobath) south of New England. In the fall, sperm whale 
occurrence south of New England on the continental shelf is at its 
highest level, and there remains a continental shelf edge occurrence in 
the mid-Atlantic bight. In winter, sperm whales are concentrated east 
and northeast of Cape Hatteras.

Long-Finned Pilot Whale

    Long-finned pilot whales prefer deep temperate to subpolar oceanic 
waters, but they have been known to occur in coastal waters in some 
areas. Larger groupings of animals have been documented on the 
continental edge and slope, depending on the season. In the Northern 
Hemisphere, their range includes the U.S. east coast, Gulf of St. 
Lawrence, the Azores, Madeira, North Africa, western Mediterranean Sea, 
North Sea, Greenland and the Barents Sea. In the winter and spring, 
they are more likely to occur in offshore oceanic waters or on the 
continental slope. In the summer and autumn, long-finned pilot whales 
generally follow their favorite foods farther inshore and on to the 
continental shelf. In U.S. Atlantic waters the species is distributed 
principally along the continental shelf edge off the northeastern U.S. 
coast in winter and early spring and in late spring, long-finned pilot 
whales move onto Georges Bank and into the Gulf of Maine and more 
northern waters and remain in these areas through late autumn (Waring 
et al., 2016).

Atlantic White-Sided Dolphin

    Atlantic white-sided dolphins are found in temperate and sub-polar 
waters of the North Atlantic, primarily in continental shelf waters to 
the 100-m depth contour from central West Greenland to North Carolina 
(Waring et al., 2016). The Gulf of Maine stock is most common in 
continental shelf waters from Hudson Canyon to Georges Bank, and in the 
Gulf of Maine and lower Bay of Fundy. Sighting data indicate seasonal 
shifts in distribution (Northridge et al., 1997). During January to 
May, low numbers of white-sided dolphins are found from Georges Bank to 
Jeffreys Ledge (off New Hampshire), with even lower numbers south of 
Georges Bank, as documented by a few strandings collected on beaches of 
Virginia to South Carolina. From June through September, large numbers 
of white-sided dolphins are found from Georges Bank to the lower Bay of 
Fundy. From October to December, white-sided dolphins occur at 
intermediate densities from southern Georges Bank to southern Gulf of 
Maine (Payne and Heinemann 1990). Sightings south of Georges Bank, 
particularly around Hudson Canyon, occur year round but at low 
densities.

Atlantic Spotted Dolphin

    Atlantic spotted dolphins are found in tropical and warm temperate 
waters ranging from southern New England, south to Gulf of Mexico and 
the Caribbean to Venezuela (Waring et al., 2014). This stock regularly 
occurs in continental shelf waters south of Cape Hatteras and in 
continental shelf edge and continental slope waters north of this 
region (Waring et al., 2014). There are two forms of this species, with 
the larger ecotype inhabiting the continental shelf and is usually 
found inside or near the 200 m isobaths (Waring et al., 2014).

Common Dolphin

    Common dolphins prefer warm tropical to cool temperate waters that 
are primarily oceanic and offshore. They can be found along the 
continental slope in waters 650 to 6,500 feet deep. The abundance and 
distribution of common dolphins vary based on interannual changes, 
oceanographic conditions, and seasons. In the western North Atlantic, 
they are often associated with the Gulf Stream current, and are more 
common north of Cape Hatteras, North Carolina. From summer through 
autumn, large aggregations of dolphins can be found near Georges Bank 
(extending from Cape Cod, Massachusetts, to Nova Scotia, Canada), 
Newfoundland, and the Scotian Shelf. In the North Atlantic, common 
dolphins are commonly found over the continental shelf between the 100-
m and 2,000-m isobaths and over prominent underwater topography and 
east to the mid-Atlantic Ridge (Waring et al., 2016).

Bottlenose Dolphin

    There are two distinct bottlenose dolphin morphotypes in the 
western North Atlantic: The coastal and offshore forms (Waring et al., 
2016). The offshore form is distributed primarily along the outer 
continental shelf and continental slope in the Northwest Atlantic Ocean 
from Georges Bank to the Florida Keys. The coastal morphotype is 
morphologically and genetically distinct from the larger, more robust 
morphotype that occupies habitats further offshore. Spatial 
distribution data, tag-telemetry studies, photo-ID studies and genetic 
studies demonstrate the existence of a distinct Northern Migratory 
stock of coastal bottlenose dolphins (Waring et al., 2014). During 
summer months (July-August), this stock occupies coastal waters from 
the shoreline to approximately the 25 m isobath between the Chesapeake 
Bay mouth and Long Island, New York; during winter months (January-
March), the stock occupies coastal waters from Cape Lookout, North 
Carolina, to the North Carolina/Virginia border (Waring et al., 2014). 
The Western North Atlantic northern migratory coastal stock and the 
Western North Atlantic

[[Page 37856]]

offshore stock may be encountered by the proposed survey.

Harbor Porpoise

    Harbor porpoises live in northern temperate and subarctic coastal 
and offshore waters. In the North Atlantic, they range from West 
Greenland to Cape Hatteras, North Carolina, and from the Barents Sea to 
West Africa. In the proposed survey areas, only the Gulf of Maine/Bay 
of Fundy stock may be present. This stock is found in U.S. and Canadian 
Atlantic waters and is concentrated in the northern Gulf of Maine and 
southern Bay of Fundy region, generally in waters less than 150 m deep 
(Waring et al., 2016). They are seen from the coastline to deep waters 
(>1800 m; Westgate et al. 1998), although the majority of the 
population is found over the continental shelf (Waring et al., 2016). 
The main threat to the species is interactions with fisheries, with 
documented take in the U.S. northeast sink gillnet, mid-Atlantic 
gillnet, and northeast bottom trawl fisheries and in the Canadian 
herring weir fisheries (Waring et al., 2016).

Harbor Seal

    The harbor seal is found in all nearshore waters of the North 
Atlantic and North Pacific Oceans and adjoining seas above about 
30[deg] N (Burns, 2009). In the western North Atlantic, harbor seals 
are distributed from the eastern Canadian Arctic and Greenland south to 
southern New England and New York, and occasionally to the Carolinas 
(Waring et al., 2016). Haul out and pupping sites are located off 
Manomet, MA and the Isles of Shoals, ME, but generally do not occur in 
areas in southern New England (Waring et al., 2016).
    Since July 2018, elevated numbers of harbor seal and gray seal 
mortalities have occurred across Maine, New Hampshire and 
Massachusetts. This event has been declared a UME. Additionally, 
stranded seals have shown clinical signs as far south as Virginia, 
although not in elevated numbers, therefore the UME investigation now 
encompasses all seal strandings from Maine to Virginia. Lastly, ice 
seals (harp and hooded seals) have also started stranding with clinical 
signs, again not in elevated numbers, and those two seal species have 
also been added to the UME investigation. As of u, 2020 a total of 
3,152 reported strandings (of all species) had occurred. Full or 
partial necropsy examinations have been conducted on some of the seals 
and samples have been collected for testing. Based on tests conducted 
thus far, the main pathogen found in the seals is phocine distemper 
virus. NMFS is performing additional testing to identify any other 
factors that may be involved in this UME. Information on this UME is 
available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Gray Seal

    There are three major populations of gray seals found in the world; 
eastern Canada (western North Atlantic stock), northwestern Europe and 
the Baltic Sea. Gray seals in the survey area belong to the western 
North Atlantic stock. The range for this stock is thought to be from 
New Jersey to Labrador. Current population trends show that gray seal 
abundance is likely increasing in the U.S. Atlantic EEZ (Waring et al., 
2016). Although the rate of increase is unknown, surveys conducted 
since their arrival in the 1980s indicate a steady increase in 
abundance in both Maine and Massachusetts (Waring et al., 2016). It is 
believed that recolonization by Canadian gray seals is the source of 
the U.S. population (Waring et al., 2016).
    As described above, elevated seal mortalities, including gray 
seals, have occurred from Maine to Virginia since July 2018. This event 
has been declared a UME, with phocine distemper virus identified as the 
main pathogen found in the seals. NMFS is performing additional testing 
to identify any other factors that may be involved in this UME. 
Information on this UME is available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Harp Seal

    The harp seal occurs throughout much of the North Atlantic and 
Arctic Oceans (Ronald and Healey 1981; Lavigne and Kovacs 1988). There 
are three harp seal stocks in the world; the only stock that may occur 
in the project area is the western North Atlantic stock which breeds 
off the coast of Newfoundland and Labrador and near the Magdalen 
Islands in the middle of the Gulf of St. Lawrence (Sergeant 1965; 
Lavigne and Kovacs 1988). Harp seals are highly migratory (Sergeant 
1965; Stenson and Sjare 1997). Breeding occurs at different times for 
each stock between late-February and April. Adults then assemble on 
suitable pack ice to undergo the annual molt. The migration then 
continues north to Arctic summer feeding grounds. In late September, 
after a summer of feeding, nearly all adults and some of the immature 
animals of the western North Atlantic stock migrate southward along the 
Labrador coast, usually reaching the entrance to the Gulf of St. 
Lawrence by early winter. The southern limit of the harp seal's habitat 
extends into the U.S. Atlantic EEZ during winter and spring. Since the 
early 1990s, numbers of sightings and strandings have been increasing 
off the east coast of the United States from Maine to New Jersey 
(Katona et al. 1993; Rubinstein 1994; Stevick and Fernald 1998; 
McAlpine 1999; Lacoste and Stenson 2000; Soulen et al. 2013). These 
appearances usually occur in January-May (Harris et al. 2002), when the 
western North Atlantic stock of harp seals is at its most southern 
point of migration.
    As described above, elevated seal mortalities, including harp 
seals, have occurred from Maine to Virginia since July 2018. This event 
has been declared a UME, with phocine distemper virus identified as the 
main pathogen found in the seals. NMFS is performing additional testing 
to identify any other factors that may be involved in this UME. 
Information on this UME is available online at: www.fisheries.noaa.gov/new-england-mid-atlantic/marine-life-distress/2018-2019-pinniped-unusual-mortality-event-along.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2016) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 dB 
threshold from the normalized composite audiograms, with the exception 
for lower limits for low-

[[Page 37857]]

frequency cetaceans where the lower bound was deemed to be biologically 
implausible and the lower bound from Southall et al. (2007) retained. 
The functional groups and the associated frequencies are indicated 
below (note that these frequency ranges correspond to the range for the 
composite group, with the entire range not necessarily reflecting the 
capabilities of every species within that group):
     Low-frequency cetaceans (mysticetes): Generalized hearing 
is estimated to occur between approximately 7 Hertz (Hz) and 35 kHz;
     Mid-frequency cetaceans (larger toothed whales, beaked 
whales, and most delphinids): Generalized hearing is estimated to occur 
between approximately 150 Hz and 160 kHz;
     High-frequency cetaceans (porpoises, river dolphins, and 
members of the genera Kogia and Cephalorhynchus; including two members 
of the genus Lagenorhynchus, on the basis of recent echolocation data 
and genetic data): Generalized hearing is estimated to occur between 
approximately 275 Hz and 160 kHz; and
     Pinnipeds in water; Phocidae (true seals): Generalized 
hearing is estimated to occur between approximately 50 Hz to 86 kH.
    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Fourteen marine mammal species (twelve cetacean and two pinniped (both 
phocid species) have the reasonable potential to co-occur with the 
proposed survey activities (see Table 3). Of the cetacean species that 
may be present, five are classified as low-frequency cetaceans (i.e., 
all mysticete species), six are classified as mid-frequency cetaceans 
(i.e., all delphinid species and the sperm whale), and one is 
classified as a high-frequency cetacean (i.e., harbor porpoise).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take section later in this document 
includes a quantitative analysis of the number of individuals that are 
expected to be taken by this activity. The Negligible Impact Analysis 
and Determination section considers the content of this section, the 
Estimated Take section, and the Proposed Mitigation section, to draw 
conclusions regarding the likely impacts of these activities on the 
reproductive success or survivorship of individuals and how those 
impacts on individuals are likely to impact marine mammal species or 
stocks.

Background on Sound

    Sound is a physical phenomenon consisting of minute vibrations that 
travel through a medium, such as air or water, and is generally 
characterized by several variables. Frequency describes the sound's 
pitch and is measured in Hz or kHz, while sound level describes the 
sound's intensity and is measured in dB. Sound level increases or 
decreases exponentially with each dB of change. The logarithmic nature 
of the scale means that each 10-dB increase is a 10-fold increase in 
acoustic power (and a 20-dB increase is then a 100-fold increase in 
power). A 10-fold increase in acoustic power does not mean that the 
sound is perceived as being 10 times louder, however. Sound levels are 
compared to a reference sound pressure ([micro]Pa) to identify the 
medium. For air and water, these reference pressures are ``re: 20 
([micro]Pa)'' and ``re: 1 [micro]Pa,'' respectively. Root mean square 
(RMS) is the quadratic mean sound pressure over the duration of an 
impulse. RMS is calculated by squaring all of the sound amplitudes, 
averaging the squares, and then taking the square root of the average 
(Urick 1975). RMS accounts for both positive and negative values; 
squaring the pressures makes all values positive so that they may be 
accounted for in the summation of pressure levels. This measurement is 
often used in the context of discussing behavioral effects, in part 
because behavioral effects, which often result from auditory cues, may 
be better expressed through averaged units rather than by peak 
pressures.
    When sound travels (propagates) from its source, its loudness 
decreases as the distance traveled by the sound increases. Thus, the 
loudness of a sound at its source is higher than the loudness of that 
same sound one km away. Acousticians often refer to the loudness of a 
sound at its source (typically referenced to one meter from the source) 
as the source level and the loudness of sound elsewhere as the received 
level (i.e., typically the receiver). For example, a humpback whale 3 
km from a device that has a source level of 230 dB may only be exposed 
to sound that is 160 dB loud, depending on how the sound travels 
through water (e.g., spherical spreading (6 dB reduction with doubling 
of distance) was used in this example). As a result, it is important to 
understand the difference between source levels and received levels 
when discussing the loudness of sound in the ocean or its impacts on 
the marine environment.
    As sound travels from a source, its propagation in water is 
influenced by various physical characteristics, including water 
temperature, depth, salinity, and surface and bottom properties that 
cause refraction, reflection, absorption, and scattering of sound 
waves. Oceans are not homogeneous and the contribution of each of these 
individual factors is extremely complex and interrelated. The physical 
characteristics that determine the sound's speed through the water will 
change with depth, season, geographic location, and with time of day 
(as a result, in actual active sonar operations, crews will measure 
oceanic conditions, such as sea water temperature and depth, to 
calibrate models that determine the path the sonar signal will take as 
it travels through the ocean and how strong the sound signal will be at 
a given range along a particular transmission path). As sound travels 
through the ocean, the intensity associated with the wavefront 
diminishes, or attenuates. This decrease in intensity is referred to as 
propagation loss, also commonly called transmission loss.

Acoustic Impacts

    Geophysical surveys may temporarily impact marine mammals in the 
area due to elevated in-water sound levels. Marine mammals are 
continually exposed to many sources of sound. Naturally occurring 
sounds such as lightning, rain, sub-sea earthquakes, and biological 
sounds (e.g., snapping shrimp, whale songs) are widespread throughout 
the world's oceans. Marine mammals produce sounds in various contexts 
and use sound for various biological functions including, but not 
limited to: (1) Social interactions; (2) foraging; (3) orientation; and 
(4) predator detection. Interference with producing or receiving these 
sounds may result in adverse impacts. Audible distance, or received 
levels of sound depend on the nature of the sound source, ambient noise 
conditions, and the sensitivity of the receptor to the sound 
(Richardson et al., 1995). Type and significance of marine mammal 
reactions to sound are likely dependent on a variety of factors 
including, but not limited to, (1) the behavioral state of the

[[Page 37858]]

animal (e.g., feeding, traveling, etc.); (2) frequency of the sound; 
(3) distance between the animal and the source; and (4) the level of 
the sound relative to ambient conditions (Southall et al., 2007).
    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Current 
data indicate that not all marine mammal species have equal hearing 
capabilities (Richardson et al., 1995; Wartzok and Ketten, 1999; Au and 
Hastings, 2008).
    Animals are less sensitive to sounds at the outer edges of their 
functional hearing range and are more sensitive to a range of 
frequencies within the middle of their functional hearing range.

Hearing Impairment

    Marine mammals may experience temporary or permanent hearing 
impairment when exposed to loud sounds. Hearing impairment is 
classified by temporary threshold shift (TTS) and permanent threshold 
shift (PTS). PTS is considered auditory injury (Southall et al., 2007) 
and occurs in a specific frequency range and amount. Irreparable damage 
to the inner or outer cochlear hair cells may cause PTS; however, other 
mechanisms are also involved, such as exceeding the elastic limits of 
certain tissues and membranes in the middle and inner ears and 
resultant changes in the chemical composition of the inner ear fluids 
(Southall et al., 2007). There are no empirical data for onset of PTS 
in any marine mammal; therefore, PTS-onset must be estimated from TTS-
onset measurements and from the rate of TTS growth with increasing 
exposure levels above the level eliciting TTS-onset. PTS is presumed to 
be likely if the hearing threshold is reduced by >= 40 dB (that is, 40 
dB of TTS).

Temporary Threshold Shift (TTS)

    TTS is the mildest form of hearing impairment that can occur during 
exposure to a loud sound (Kryter 1985). While experiencing TTS, the 
hearing threshold rises and a sound must be stronger in order to be 
heard. At least in terrestrial mammals, TTS can last from minutes or 
hours to (in cases of strong TTS) days, can be limited to a particular 
frequency range, and can occur to varying degrees (i.e., a loss of a 
certain number of dBs of sensitivity). For sound exposures at or 
somewhat above the TTS threshold, hearing sensitivity in both 
terrestrial and marine mammals recovers rapidly after exposure to the 
noise ends.
    Marine mammal hearing plays a critical role in communication with 
conspecifics and in interpretation of environmental cues for purposes 
such as predator avoidance and prey capture. Depending on the degree 
(elevation of threshold in dB), duration (i.e., recovery time), and 
frequency range of TTS and the context in which it is experienced, TTS 
can have effects on marine mammals ranging from discountable to 
serious. For example, a marine mammal may be able to readily compensate 
for a brief, relatively small amount of TTS in a non-critical frequency 
range that takes place during a time when the animals is traveling 
through the open ocean, where ambient noise is lower and there are not 
as many competing sounds present. Alternatively, a larger amount and 
longer duration of TTS sustained during a time when communication is 
critical for successful mother/calf interactions could have more 
serious impacts if it were in the same frequency band as the necessary 
vocalizations and of a severity that it impeded communication. The fact 
that animals exposed to levels and durations of sound that would be 
expected to result in this physiological response would also be 
expected to have behavioral responses of a comparatively more severe or 
sustained nature is also notable and potentially of more importance 
than the simple existence of a TTS.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin, beluga whale (Delphinapterus leucas), harbor 
porpoise, and Yangtze finless porpoise (Neophocaena phocaenoides)) and 
three species of pinnipeds (northern elephant seal (Mirounga 
angustirostris), harbor seal, and California sea lion (Zalophus 
californianus)) exposed to a limited number of sound sources (i.e., 
mostly tones and octave-band noise) in laboratory settings (e.g., 
Finneran et al., 2002 and 2010; Nachtigall et al., 2004; Kastak et al., 
2005; Lucke et al., 2009; Mooney et al., 2009; Popov et al., 2011; 
Finneran and Schlundt, 2010). In general, harbor seals (Kastak et al., 
2005; Kastelein et al., 2012a) and harbor porpoises (Lucke et al., 
2009; Kastelein et al., 2012b) have a lower TTS onset than other 
measured pinniped or cetacean species. However, even for these animals, 
which are better able to hear higher frequencies and may be more 
sensitive to higher frequencies, exposures on the order of 
approximately 170 dB RMS or higher for brief transient signals are 
likely required for even temporary (recoverable) changes in hearing 
sensitivity that would likely not be categorized as physiologically 
damaging (Lucke et al., 2009). Additionally, the existing marine mammal 
TTS data come from a limited number of individuals within these 
species. There are no data available on noise-induced hearing loss for 
mysticetes. For summaries of data on TTS in marine mammals or for 
further discussion of TTS onset thresholds, please see Finneran (2015).
    Scientific literature highlights the inherent complexity of 
predicting TTS onset in marine mammals, as well as the importance of 
considering exposure duration when assessing potential impacts (Mooney 
et al., 2009a, 2009b; Kastak et al., 2007). Generally, with sound 
exposures of equal energy, quieter sounds (lower sound pressure levels 
(SPL)) of longer duration were found to induce TTS onset more than 
louder sounds (higher SPL) of shorter duration (more similar to sub-
bottom profilers). For intermittent sounds, less threshold shift will 
occur than from a continuous exposure with the same energy (some 
recovery will occur between intermittent exposures) (Kryter et al., 
1966; Ward 1997). For sound exposures at or somewhat above the TTS-
onset threshold, hearing sensitivity recovers rapidly after exposure to 
the sound ends; intermittent exposures recover faster in comparison 
with continuous exposures of the same duration (Finneran et al., 2010). 
NMFS considers TTS as a non-injurious effect that is mediated by 
physiological effects on the auditory system.
    Animals in the survey areas during proposed surveys are unlikely to 
incur TTS hearing impairment due to the characteristics of the sound 
sources, which include low source levels (208 to 221 dB re 1 [micro]Pa-
m) and generally very short pulses and duration of the sound. Even for 
high-frequency cetacean species (e.g., harbor porpoises), which may 
have increased sensitivity to TTS (Lucke et al., 2009; Kastelein et 
al., 2012b), individuals would have to make a very close approach and 
also remain very close to vessels operating these sources in order to 
receive multiple exposures at relatively high levels, as would be 
necessary to cause TTS. Intermittent exposures--as would occur due to 
the brief, transient signals produced by these sources--require a 
higher cumulative SEL to induce TTS than would continuous exposures of 
the same duration (i.e., intermittent exposure results in lower levels 
of TTS) (Mooney et al., 2009a; Finneran et al., 2010). Moreover, most 
marine mammals would more likely avoid a loud sound source rather than 
swim in such close proximity as to result in TTS. Kremser

[[Page 37859]]

et al. (2005) noted that the probability of a cetacean swimming through 
the area of exposure when a sub-bottom profiler emits a pulse is 
small--because if the animal was in the area, it would have to pass the 
transducer at close range in order to be subjected to sound levels that 
could cause TTS and would likely exhibit avoidance behavior to the area 
near the transducer rather than swim through at such a close range. 
Further, the restricted beam shape of the majority of the geophysical 
survey equipment planned for use (Table 2) makes it unlikely that an 
animal would be exposed more than briefly during the passage of the 
vessel.

Masking

    Masking is the obscuring of sounds of interest to an animal by 
other sounds, typically at similar frequencies. Marine mammals are 
highly dependent on sound, and their ability to recognize sound signals 
amid other sound is important in communication and detection of both 
predators and prey (Tyack 2000). Background ambient sound may interfere 
with or mask the ability of an animal to detect a sound signal even 
when that signal is above its absolute hearing threshold. Even in the 
absence of anthropogenic sound, the marine environment is often loud. 
Natural ambient sound includes contributions from wind, waves, 
precipitation, other animals, and (at frequencies above 30 kHz) thermal 
sound resulting from molecular agitation (Richardson et al., 1995).
    Background sound may also include anthropogenic sound, and masking 
of natural sounds can result when human activities produce high levels 
of background sound. Conversely, if the background level of underwater 
sound is high (e.g., on a day with strong wind and high waves), an 
anthropogenic sound source would not be detectable as far away as would 
be possible under quieter conditions and would itself be masked. 
Ambient sound is highly variable on continental shelves (Myrberg 1978; 
Desharnais et al., 1999). This results in a high degree of variability 
in the range at which marine mammals can detect anthropogenic sounds.
    Although masking is a phenomenon which may occur naturally, the 
introduction of loud anthropogenic sounds into the marine environment 
at frequencies important to marine mammals increases the severity and 
frequency of occurrence of masking. For example, if a baleen whale is 
exposed to continuous low-frequency sound from an industrial source, 
this would reduce the size of the area around that whale within which 
it can hear the calls of another whale. The components of background 
noise that are similar in frequency to the signal in question primarily 
determine the degree of masking of that signal. In general, little is 
known about the degree to which marine mammals rely upon detection of 
sounds from conspecifics, predators, prey, or other natural sources. In 
the absence of specific information about the importance of detecting 
these natural sounds, it is not possible to predict the impact of 
masking on marine mammals (Richardson et al., 1995). In general, 
masking effects are expected to be less severe when sounds are 
transient than when they are continuous. Masking is typically of 
greater concern for those marine mammals that utilize low-frequency 
communications, such as baleen whales, because of how far low-frequency 
sounds propagate.
    Marine mammal communications would not likely be masked appreciably 
by the sub-bottom profiler signals given the directionality of the 
signals (for most geophysical survey equipment types planned for use 
(Table 2)) and the brief period when an individual mammal is likely to 
be within its beam.

Non-Auditory Physical Effects (Stress)

    Classic stress responses begin when an animal's central nervous 
system perceives a potential threat to its homeostasis. That perception 
triggers stress responses regardless of whether a stimulus actually 
threatens the animal; the mere perception of a threat is sufficient to 
trigger a stress response (Moberg 2000; Seyle 1950). Once an animal's 
central nervous system perceives a threat, it mounts a biological 
response or defense that consists of a combination of the four general 
biological defense responses: Behavioral responses, autonomic nervous 
system responses, neuroendocrine responses, or immune responses.
    In the case of many stressors, an animal's first and sometimes most 
economical (in terms of biotic costs) response is behavioral avoidance 
of the potential stressor or avoidance of continued exposure to a 
stressor. An animal's second line of defense to stressors involves the 
sympathetic part of the autonomic nervous system and the classical 
``fight or flight'' response which includes the cardiovascular system, 
the gastrointestinal system, the exocrine glands, and the adrenal 
medulla to produce changes in heart rate, blood pressure, and 
gastrointestinal activity that humans commonly associate with 
``stress.'' These responses have a relatively short duration and may or 
may not have significant long-term effect on an animal's welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine systems; the system that has received the most study has 
been the hypothalamus-pituitary-adrenal system (also known as the HPA 
axis in mammals). Unlike stress responses associated with the autonomic 
nervous system, virtually all neuro-endocrine functions that are 
affected by stress--including immune competence, reproduction, 
metabolism, and behavior--are regulated by pituitary hormones. Stress-
induced changes in the secretion of pituitary hormones have been 
implicated in failed reproduction (Moberg 1987; Rivier 1995), altered 
metabolism (Elasser et al., 2000), reduced immune competence (Blecha 
2000), and behavioral disturbance. Increases in the circulation of 
glucocorticosteroids (cortisol, corticosterone, and aldosterone in 
marine mammals; see Romano et al., 2004) have been equated with stress 
for many years.
    The primary distinction between stress (which is adaptive and does 
not normally place an animal at risk) and distress is the biotic cost 
of the response. During a stress response, an animal uses glycogen 
stores that can be quickly replenished once the stress is alleviated. 
In such circumstances, the cost of the stress response would not pose a 
risk to the animal's welfare. However, when an animal does not have 
sufficient energy reserves to satisfy the energetic costs of a stress 
response, energy resources must be diverted from other biotic function, 
which impairs those functions that experience the diversion. For 
example, when mounting a stress response diverts energy away from 
growth in young animals, those animals may experience stunted growth. 
When mounting a stress response diverts energy from a fetus, an 
animal's reproductive success and its fitness will suffer. In these 
cases, the animals will have entered a pre-pathological or pathological 
state which is called ``distress'' (Seyle 1950) or ``allostatic 
loading'' (McEwen and Wingfield 2003). This pathological state will 
last until the animal replenishes its biotic reserves sufficient to 
restore normal function. Note that these examples involved a long-term 
(days or weeks) stress response exposure to stimuli.
    Relationships between these physiological mechanisms, animal 
behavior, and the costs of stress responses have also been documented 
fairly well through controlled experiments; because this physiology 
exists in every vertebrate that has been

[[Page 37860]]

studied, it is not surprising that stress responses and their costs 
have been documented in both laboratory and free-living animals (for 
examples see, Holberton et al., 1996; Hood et al., 1998; Jessop et al., 
2003; Krausman et al., 2004; Lankford et al., 2005; Reneerkens et al., 
2002; Thompson and Hamer, 2000). Information has also been collected on 
the physiological responses of marine mammals to exposure to 
anthropogenic sounds (Fair and Becker 2000; Romano et al., 2002). For 
example, Rolland et al. (2012) found that noise reduction from reduced 
ship traffic in the Bay of Fundy was associated with decreased stress 
in North Atlantic right whales.
    Studies of other marine animals and terrestrial animals would also 
lead us to expect some marine mammals to experience physiological 
stress responses and, perhaps, physiological responses that would be 
classified as ``distress'' upon exposure to high frequency, mid-
frequency and low-frequency sounds. For example, Jansen (1998) reported 
on the relationship between acoustic exposures and physiological 
responses that are indicative of stress responses in humans (for 
example, elevated respiration and increased heart rates). Jones (1998) 
reported on reductions in human performance when faced with acute, 
repetitive exposures to acoustic disturbance. Trimper et al. (1998) 
reported on the physiological stress responses of osprey to low-level 
aircraft noise while Krausman et al. (2004) reported on the auditory 
and physiology stress responses of endangered Sonoran pronghorn to 
military overflights. Smith et al. (2004a, 2004b), for example, 
identified noise-induced physiological transient stress responses in 
hearing-specialist fish (i.e., goldfish) that accompanied short- and 
long-term hearing losses. Welch and Welch (1970) reported physiological 
and behavioral stress responses that accompanied damage to the inner 
ears of fish and several mammals.
    Hearing is one of the primary senses marine mammals use to gather 
information about their environment and to communicate with 
conspecifics. Although empirical information on the relationship 
between sensory impairment (TTS, PTS, and acoustic masking) on marine 
mammals remains limited, it seems reasonable to assume that reducing an 
animal's ability to gather information about its environment and to 
communicate with other members of its species would be stressful for 
animals that use hearing as their primary sensory mechanism. Therefore, 
we assume that acoustic exposures sufficient to trigger onset PTS or 
TTS would be accompanied by physiological stress responses because 
terrestrial animals exhibit those responses under similar conditions 
(NRC 2003). More importantly, marine mammals might experience stress 
responses at received levels lower than those necessary to trigger 
onset TTS. Based on empirical studies of the time required to recover 
from stress responses (Moberg 2000), we also assume that stress 
responses are likely to persist beyond the time interval required for 
animals to recover from TTS and might result in pathological and pre-
pathological states that would be as significant as behavioral 
responses to TTS.
    In general, there is a small amount of data available on the 
potential for strong, anthropogenic underwater sounds to cause non-
auditory physical effects in marine mammals. The available data do not 
allow identification of a specific exposure level above which non-
auditory effects can be expected (Southall et al., 2007). There is no 
definitive evidence that any of these effects occur even for marine 
mammals in close proximity to an anthropogenic sound source. In 
addition, marine mammals that show behavioral avoidance of survey 
vessels and related sound sources are unlikely to incur non-auditory 
impairment or other physical effects. NMFS does not expect that the 
generally short-term, intermittent, and transitory HRG and geotechnical 
activities would create conditions of long-term, continuous noise and 
chronic acoustic exposure leading to long-term physiological stress 
responses in marine mammals.

Behavioral Disturbance

    Behavioral disturbance may include a variety of effects, including 
subtle changes in behavior (e.g., minor or brief avoidance of an area 
or changes in vocalizations), more conspicuous changes in similar 
behavioral activities, and more sustained and/or potentially severe 
reactions, such as displacement from or abandonment of high-quality 
habitat. Behavioral responses to sound are highly variable and context-
specific and any reactions depend on numerous intrinsic and extrinsic 
factors (e.g., species, state of maturity, experience, current 
activity, reproductive state, auditory sensitivity, time of day), as 
well as the interplay between factors (e.g., Richardson et al., 1995; 
Wartzok et al., 2003; Southall et al., 2007; Weilgart, 2007; Archer et 
al., 2010). Behavioral reactions can vary not only among individuals 
but also within an individual, depending on previous experience with a 
sound source, context, and numerous other factors (Ellison et al., 
2012), and can vary depending on characteristics associated with the 
sound source (e.g., whether it is moving or stationary, number of 
sources, distance from the source). Please see Appendices B-C of 
Southall et al. (2007) for a review of studies involving marine mammal 
behavioral responses to sound.
    Habituation can occur when an animal's response to a stimulus wanes 
with repeated exposure, usually in the absence of unpleasant associated 
events (Wartzok et al., 2003). Animals are most likely to habituate to 
sounds that are predictable and unvarying. It is important to note that 
habituation is appropriately considered as a ``progressive reduction in 
response to stimuli that are perceived as neither aversive nor 
beneficial,'' rather than as, more generally, moderation in response to 
human disturbance (Bejder et al., 2009). The opposite process is 
sensitization, when an unpleasant experience leads to subsequent 
responses, often in the form of avoidance, at a lower level of 
exposure. As noted, behavioral state may affect the type of response. 
For example, animals that are resting may show greater behavioral 
change in response to disturbing sound levels than animals that are 
highly motivated to remain in an area for feeding (Richardson et al., 
1995; NRC 2003; Wartzok et al., 2003). Controlled experiments with 
captive marine mammals have shown pronounced behavioral reactions, 
including avoidance of loud sound sources (Ridgway et al., 1997; 
Finneran et al., 2003). Observed responses of wild marine mammals to 
loud, pulsed sound sources (typically seismic airguns or acoustic 
harassment devices) have been varied but often consist of avoidance 
behavior or other behavioral changes suggesting discomfort (Morton and 
Symonds, 2002; see also Richardson et al., 1995; Nowacek et al., 2007).
    Available studies show wide variation in response to underwater 
sound; therefore, it is difficult to predict specifically how any given 
sound in a particular instance might affect marine mammals perceiving 
the signal. If a marine mammal does react briefly to an underwater 
sound by changing its behavior or moving a small distance, the impacts 
of the change are unlikely to be significant to the individual, let 
alone the stock or population. However, if a sound source displaces 
marine mammals from an important feeding or breeding area for a 
prolonged period, impacts on individuals and populations could be 
significant (e.g., Lusseau and

[[Page 37861]]

Bejder, 2007; Weilgart 2007; NRC 2005). However, there are broad 
categories of potential response, which we describe in greater detail 
here, that include alteration of dive behavior, alteration of foraging 
behavior, effects to breathing, interference with or alteration of 
vocalization, avoidance, and flight.
    Changes in dive behavior can vary widely and may consist of 
increased or decreased dive times and surface intervals as well as 
changes in the rates of ascent and descent during a dive (e.g., Frankel 
and Clark 2000; Costa et al., 2003; Ng and Leung 2003; Nowacek et al., 
2004; Goldbogen et al., 2013a,b). Variations in dive behavior may 
reflect interruptions in biologically significant activities (e.g., 
foraging) or they may be of little biological significance. The impact 
of an alteration to dive behavior resulting from an acoustic exposure 
depends on what the animal is doing at the time of the exposure and the 
type and magnitude of the response.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al., 
2001; Nowacek et al.; 2004; Madsen et al., 2006; Yazvenko et al., 
2007). A determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    Variations in respiration naturally vary with different behaviors 
and alterations to breathing rate as a function of acoustic exposure 
can be expected to co-occur with other behavioral reactions, such as a 
flight response or an alteration in diving. However, respiration rates 
in and of themselves may be representative of annoyance or an acute 
stress response. Various studies have shown that respiration rates may 
either be unaffected or could increase, depending on the species and 
signal characteristics, again highlighting the importance in 
understanding species differences in the tolerance of underwater noise 
when determining the potential for impacts resulting from anthropogenic 
sound exposure (e.g., Kastelein et al., 2001, 2005b, 2006; Gailey et 
al., 2007).
    Marine mammals vocalize for different purposes and across multiple 
modes, such as whistling, echolocation click production, calling, and 
singing. Changes in vocalization behavior in response to anthropogenic 
noise can occur for any of these modes and may result from a need to 
compete with an increase in background noise or may reflect increased 
vigilance or a startle response. For example, in the presence of 
potentially masking signals, humpback whales and killer whales have 
been observed to increase the length of their songs (Miller et al., 
2000; Fristrup et al., 2003; Foote et al., 2004), while right whales 
have been observed to shift the frequency content of their calls upward 
while reducing the rate of calling in areas of increased anthropogenic 
noise (Parks et al., 2007b). In some cases, animals may cease sound 
production during production of aversive signals (Bowles et al., 1994).
    Avoidance is the displacement of an individual from an area or 
migration path as a result of the presence of a sound or other 
stressors, and is one of the most obvious manifestations of disturbance 
in marine mammals (Richardson et al., 1995). For example, gray whales 
are known to change direction--deflecting from customary migratory 
paths--in order to avoid noise from seismic surveys (Malme et al., 
1984). Avoidance may be short-term, with animals returning to the area 
once the noise has ceased (e.g., Bowles et al., 1994; Goold 1996; Stone 
et al., 2000; Morton and Symonds, 2002; Gailey et al., 2007). Longer-
term displacement is possible, however, which may lead to changes in 
abundance or distribution patterns of the affected species in the 
affected region if habituation to the presence of the sound does not 
occur (e.g., Blackwell et al., 2004; Bejder et al., 2006; Teilmann et 
al., 2006).
    A flight response is a dramatic change in normal movement to a 
directed and rapid movement away from the perceived location of a sound 
source. The flight response differs from other avoidance responses in 
the intensity of the response (e.g., directed movement, rate of 
travel). Relatively little information on flight responses of marine 
mammals to anthropogenic signals exist, although observations of flight 
responses to the presence of predators have occurred (Connor and 
Heithaus, 1996). The result of a flight response could range from 
brief, temporary exertion and displacement from the area where the 
signal provokes flight to, in extreme cases, marine mammal strandings 
(Evans and England, 2001). However, it should be noted that response to 
a perceived predator does not necessarily invoke flight (Ford and 
Reeves, 2008) and whether individuals are solitary or in groups may 
influence the response.
    Behavioral disturbance can also impact marine mammals in more 
subtle ways. Increased vigilance may result in costs related to 
diversion of focus and attention (i.e., when a response consists of 
increased vigilance, it may come at the cost of decreased attention to 
other critical behaviors such as foraging or resting). These effects 
have generally not been demonstrated for marine mammals, but studies 
involving fish and terrestrial animals have shown that increased 
vigilance may substantially reduce feeding rates (e.g., Beauchamp and 
Livoreil, 1997; Fritz et al., 2002; Purser and Radford, 2011). In 
addition, chronic disturbance can cause population declines through 
reduction of fitness (e.g., decline in body condition) and subsequent 
reduction in reproductive success, survival, or both (e.g., Harrington 
and Veitch, 1992; Daan et al., 1996; Bradshaw et al., 1998). However, 
Ridgway et al. (2006) reported that increased vigilance in bottlenose 
dolphins exposed to sound over a five-day period did not cause any 
sleep deprivation or stress effects.
    Many animals perform vital functions, such as feeding, resting, 
traveling, and socializing, on a diel cycle (24-hour cycle). Disruption 
of such functions resulting from reactions to stressors such as sound 
exposure are more likely to be significant if they last more than one 
diel cycle or recur on subsequent days (Southall et al., 2007). 
Consequently, a behavioral response lasting less than one day and not 
recurring on subsequent days is not considered particularly severe 
unless it could directly affect reproduction or survival (Southall et 
al., 2007). Note that there is a difference between multi-day 
substantive behavioral reactions and multi-day anthropogenic 
activities. For example, just because an activity lasts for multiple 
days does not necessarily mean that individual animals are either 
exposed to activity-related stressors for multiple days or, further, 
exposed in a manner resulting in sustained multi-day substantive 
behavioral responses.
    Marine mammals are likely to avoid the HRG survey activity, 
especially the naturally shy harbor porpoise, while the harbor seals 
might be attracted to them out of curiosity. However, because the sub-
bottom profilers and other HRG survey equipment operate from a moving 
vessel, and the maximum radius to the Level B harassment threshold is

[[Page 37862]]

relatively small, the area and time that this equipment would be 
affecting a given location is very small. Further, once an area has 
been surveyed, it is not likely that it will be surveyed again, thereby 
reducing the likelihood of repeated HRG-related impacts within the 
survey area.
    We have also considered the potential for severe behavioral 
responses such as stranding and associated indirect injury or mortality 
from Equinor's use of HRG survey equipment, on the basis of a 2008 mass 
stranding of approximately 100 melon-headed whales in a Madagascar 
lagoon system. An investigation of the event indicated that use of a 
high-frequency mapping system (12-kHz multibeam echosounder) was the 
most plausible and likely initial behavioral trigger of the event, 
while providing the caveat that there is no unequivocal and easily 
identifiable single cause (Southall et al., 2013). The investigatory 
panel's conclusion was based on (1) very close temporal and spatial 
association and directed movement of the survey with the stranding 
event; (2) the unusual nature of such an event coupled with previously 
documented apparent behavioral sensitivity of the species to other 
sound types (Southall et al., 2006; Brownell et al., 2009); and (3) the 
fact that all other possible factors considered were determined to be 
unlikely causes. Specifically, regarding survey patterns prior to the 
event and in relation to bathymetry, the vessel transited in a north-
south direction on the shelf break parallel to the shore, ensonifying 
large areas of deep-water habitat prior to operating intermittently in 
a concentrated area offshore from the stranding site; this may have 
trapped the animals between the sound source and the shore, thus 
driving them towards the lagoon system. The investigatory panel 
systematically excluded or deemed highly unlikely nearly all potential 
reasons for these animals leaving their typical pelagic habitat for an 
area extremely atypical for the species (i.e., a shallow lagoon 
system). Notably, this was the first time that such a system has been 
associated with a stranding event. The panel also noted several site- 
and situation-specific secondary factors that may have contributed to 
the avoidance responses that led to the eventual entrapment and 
mortality of the whales. Specifically, shoreward-directed surface 
currents and elevated chlorophyll levels in the area preceding the 
event may have played a role (Southall et al., 2013). The report also 
notes that prior use of a similar system in the general area may have 
sensitized the animals and also concluded that, for odontocete 
cetaceans that hear well in higher frequency ranges where ambient noise 
is typically quite low, high-power active sonars operating in this 
range may be more easily audible and have potential effects over larger 
areas than low frequency systems that have more typically been 
considered in terms of anthropogenic noise impacts. It is, however, 
important to note that the relatively lower output frequency, higher 
output power, and complex nature of the system implicated in this 
event, in context of the other factors noted here, likely produced a 
fairly unusual set of circumstances that indicate that such events 
would likely remain rare and are not necessarily relevant to use of 
lower-power, higher-frequency systems more commonly used for HRG survey 
applications. The risk of similar events recurring may be very low, 
given the extensive use of active acoustic systems used for scientific 
and navigational purposes worldwide on a daily basis and the lack of 
direct evidence of such responses previously reported.

Tolerance

    Numerous studies have shown that underwater sounds from industrial 
activities are often readily detectable by marine mammals in the water 
at distances of many km. However, other studies have shown that marine 
mammals at distances more than a few km away often show no apparent 
response to industrial activities of various types (Miller et al., 
2005). This is often true even in cases when the sounds must be readily 
audible to the animals based on measured received levels and the 
hearing sensitivity of that mammal group. Although various baleen 
whales, toothed whales, and (less frequently) pinnipeds have been shown 
to react behaviorally to underwater sound from sources such as airgun 
pulses or vessels under some conditions, at other times, mammals of all 
three types have shown no overt reactions (e.g., Malme et al., 1986; 
Richardson et al., 1995; Madsen and Mohl 2000; Croll et al., 2001; 
Jacobs and Terhune 2002; Madsen et al., 2002; Miller et al., 2005). In 
general, pinnipeds seem to be more tolerant of exposure to some types 
of underwater sound than are baleen whales. Richardson et al. (1995) 
found that vessel sound does not seem to affect pinnipeds that are 
already in the water.

Vessel Strike

    Ship strikes of marine mammals can cause major wounds, which may 
lead to the death of the animal. An animal at the surface could be 
struck directly by a vessel, a surfacing animal could hit the bottom of 
a vessel, or a vessel's propeller could injure an animal just below the 
surface. The severity of injuries typically depends on the size and 
speed of the vessel (Knowlton and Kraus 2001; Laist et al., 2001; 
Vanderlaan and Taggart 2007).
    The most vulnerable marine mammals are those that spend extended 
periods of time at the surface in order to restore oxygen levels within 
their tissues after deep dives (e.g., the sperm whale). In addition, 
some baleen whales, such as the North Atlantic right whale, seem 
generally unresponsive to vessel sound, making them more susceptible to 
vessel collisions (Nowacek et al., 2004). These species are primarily 
large, slow moving whales. Smaller marine mammals (e.g., bottlenose 
dolphin) move quickly through the water column and are often seen 
riding the bow wave of large ships. Marine mammal responses to vessels 
may include avoidance and changes in dive pattern (NRC 2003).
    An examination of all known ship strikes from all shipping sources 
(civilian and military) indicates vessel speed is a principal factor in 
whether a vessel strike results in death (Knowlton and Kraus 2001; 
Laist et al., 2001; Jensen and Silber 2003; Vanderlaan and Taggart 
2007). In assessing records with known vessel speeds, Laist et al. 
(2001) found a direct relationship between the occurrence of a whale 
strike and the speed of the vessel involved in the collision. The 
authors concluded that most deaths occurred when a vessel was traveling 
in excess of 24.1 km/h (14.9 mph; 13 kn). Given the slow vessel speeds 
and predictable course necessary for data acquisition, ship strike is 
unlikely to occur during the geophysical and geotechnical surveys. 
Marine mammals would be able to easily avoid the survey vessel due to 
the slow vessel speed. Further, Equinor would implement measures (e.g., 
protected species monitoring, vessel speed restrictions and separation 
distances; see Proposed Mitigation) set forth in the BOEM lease to 
reduce the risk of a vessel strike to marine mammal species in the 
survey area.

Marine Mammal Habitat

    The HRG survey equipment will not contact the seafloor and does not 
represent a source of pollution. We are not aware of any available 
literature on impacts to marine mammal prey from sound produced by HRG 
survey equipment. However, as the HRG survey equipment introduces noise 
to the marine environment, there is the

[[Page 37863]]

potential for it to result in avoidance of the area around the HRG 
survey activities on the part of marine mammal prey. Any avoidance of 
the area on the part of marine mammal prey would be expected to be 
short term and temporary.
    Because of the temporary nature of the disturbance, and the 
availability of similar habitat and resources (e.g., prey species) in 
the surrounding area, 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. Impacts on marine mammal habitat from the proposed 
activities will be temporary, insignificant, and discountable.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization 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 would be by Level B harassment only, in the form 
of disruption of behavioral patterns for individual marine mammals 
resulting from exposure to HRG sources. Based on the nature of the 
activity and the anticipated effectiveness of the mitigation measures 
(i.e., exclusion zones and shutdown measures), discussed in detail 
below in Proposed Mitigation section, Level A harassment is neither 
anticipated nor proposed to be authorized.
    As described previously, no mortality is anticipated or proposed to 
be 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 behaviorally harassed or incur some 
degree of permanent 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 proposed take 
estimate.

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--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 160 dB re 1 [mu]Pa (rms) 
for impulsive and/or intermittent sources (e.g., impact pile driving) 
and 120 dB rms for continuous sources (e.g., vibratory driving). 
Equinor's proposed activity includes the use of intermittent sources 
(geophysical survey equipment) and therefore use of the 160 dB re 1 
[mu]Pa (rms) threshold is applicable.
    Level A harassment--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). The 
components of Equinor's proposed activity that may result in the take 
of marine mammals include the use of impulsive and non-impulsive 
intermittent sources.
    These thresholds are provided in Table 4 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: 
www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--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)..................  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
(Underwater)...........................   LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW).................  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
(Underwater)...........................   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.

[[Page 37864]]

 
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.
    The proposed survey would entail the use of HRG equipment. The 
distance to the isopleth corresponding to the threshold for Level B 
harassment was calculated for all HRG equipment with the potential to 
result in harassment of marine mammals. NMFS has developed an interim 
methodology for determining the rms sound pressure level 
(SPLrms) at the 160-dB isopleth for the purposes of 
estimating take by Level B harassment resulting from exposure to HRG 
survey equipment (NMFS, 2019). This methodology incorporates frequency 
and some directionality to refine estimated ensonified zones and is 
described below:

If only peak source sound pressure level (SPLpk) is given, 
the SPLrms can be roughly approximated by:

(1) SPLrms = SPLpk + 10log10 [tau]

where [tau] is the pulse duration in second. If the pulse duration 
varies, the longest duration should be used, unless there is certainty 
regarding the portion of time a shorter duration will be used, in which 
case the result can be calculated/parsed appropriately.
    In order to account for the greater absorption of higher frequency 
sources, we recommend applying 20 log(r) with an absorption term 
[alpha] r/1000 to calculate transmission loss (TL), as described in 
Eq.s (2) and (3) below:

(2) TL = 20log10(r) + [alpha] . r/1000 (dB)

where r is the distance in meters, and [alpha] is absorption 
coefficient in dB/km.
    While the calculation of absorption coefficient varies with 
frequency, temperature, salinity, and pH, the largest factor driving 
the absorption coefficient is frequency. A simple formula to 
approximate the absorption coefficient (neglecting temperature, 
salinity, and pH) is provided by Richardson et al. (1995):

(3) [alpha] ~ 0.036f1.5 (dB/km)

where f is frequency in kHz. When a range of frequencies, is being 
used, the lower bound of the range should be used for this calculation, 
unless there is certainty regarding the portion of time a higher 
frequency will be used, in which case the result can be calculated/
parsed appropriately.
    Further, if the beamwidth is less than 180[deg] and the angle of 
beam axis in respect to sea surface is known, the horizontal impact 
distance R should be calculated using
[GRAPHIC] [TIFF OMITTED] TN24JN20.001

    where SL is the SPLrms at the source (1 m), q is the 
beamwidth (in radian), and u is the angle of beam axis in respect to 
sea surface (in radian).
    Finally, if the beam is pointed at a normal downward direction, Eq. 
(4) can be simplified as:
[GRAPHIC] [TIFF OMITTED] TN24JN20.002

    The interim methodology described above was used to estimate 
isopleth distances to the Level B harassment threshold for the proposed 
HRG survey. NMFS considers the data provided by Crocker and Fratantonio 
(2016) to represent the best available information on source levels 
associated with HRG equipment and therefore recommends that source 
levels provided by Crocker and Fratantonio (2016) be incorporated in 
the method described above to estimate isopleth distances to the Level 
B harassment threshold. In cases when the source level for a specific 
type of HRG equipment is not provided in Crocker and Fratantonio 
(2016), NMFS recommends that either the source levels provided by the 
manufacturer be used, or, in instances where source levels provided by 
the manufacturer are unavailable or unreliable, a proxy from Crocker 
and Fratantonio (2016) be used instead. Table 2 shows the HRG equipment 
types that may be used during the proposed vessel-based surveys that 
may result in take of marine mammals, and the sound levels associated 
with those HRG equipment types.
    Results of modeling using the methodology described above indicated 
that, of the HRG survey equipment planned for use by Equinor that has 
the potential to result in harassment of marine mammals, sound produced 
by the GeoSource 800 J sparker would propagate furthest to the Level B 
harassment threshold (Table 5); therefore, for the purposes of the 
exposure analysis, it was assumed the GeoSource 800 J would be active 
during the entirety of the survey. Thus, the distance to the isopleth 
corresponding to the threshold for Level B harassment for the GeoSource 
800 J (estimated at 141 m; Table 5) was used as the basis of the take 
calculation for all marine mammals. We note that this is a conservative 
assumption as there may be times during the proposed surveys when the 
GeoSource 800 J is not operated; if this were the case, the potential 
for the take of marine mammals by Level B harassment during these times 
would be much lower based on the modeled distance to the Level B 
harassment threshold associated with the USBL (Table 5).

[[Page 37865]]



     Table 5--Modeled Radial Distances From HRG Survey Equipment to Isopleths Corresponding to Level A Harassment and Level B Harassment Thresholds
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                            Radial distance to Level A harassment threshold (m)                         Radial distance
                                     -------------------------------------------------------------------------------------------------     to Level B
                                                                                                                                           harassment
            Sound source                   Low frequency            Mid frequency          High frequency         Phocid pinnipeds       threshold (m)
                                       cetaceans  (peak SPL/    cetaceans  (peak SPL/   cetaceans  (peak SPL/    (underwater)  (peak  ------------------
                                              SELcum)                  SELcum)                 SELcum)               SPL/SELcum)           All marine
                                                                                                                                            mammals
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kongsberg HiPAP.....................  0......................  0.....................  0.....................  0.....................                  4
501/502 USBL........................
Geo-Source 400 Tip Sparker (800 J)..  -/<1...................  -/0...................  3.5/<1................  -/<1..................                141
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Predicted distances to Level A harassment isopleths, which vary 
based on marine mammal functional hearing groups (Table 5), were also 
calculated. The updated acoustic thresholds for impulsive sounds (such 
as HRG survey equipment) contained in the Technical Guidance (NMFS, 
2018) were presented as dual metric acoustic thresholds using both 
cumulative sound exposure level (SELcum) and peak sound 
pressure level metrics. As dual metrics, NMFS considers onset of PTS 
(Level A harassment) to have occurred when either one of the two 
metrics is exceeded (i.e., the metric resulting in the largest 
isopleth). The SELcum metric considers both level and 
duration of exposure, as well as auditory weighting functions by marine 
mammal hearing group.
    Modeled distances to isopleths corresponding to the Level A 
harassment thresholds are very small (< 4 m) for all marine mammal 
species and stocks that may be impacted by the proposed activities 
(Table 5). Based on the very small Level A harassment zones for all 
marine mammal species and stocks that may be impacted by the proposed 
activities, the potential for any marine mammals to be taken by Level A 
harassment is considered so low as to be discountable. As NMFS has 
determined that the likelihood of take in the form of Level A 
harassment of any marine mammals as a result of the proposed surveys is 
so low as to be discountable, we therefore do not propose to authorize 
the take by Level A harassment of any marine mammals.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations.
    The habitat-based density models produced by the Duke University 
Marine Geospatial Ecology Laboratory (MGEL) (Roberts et al., 2016, 
2017, 2018) represent the best available information regarding marine 
mammal densities in the proposed survey area. The density data 
presented by the Duke University MGEL incorporates aerial and shipboard 
line-transect survey data from NMFS and other organizations and 
incorporates data from 8 physiographic and 16 dynamic oceanographic and 
biological covariates, and controls for the influence of sea state, 
group size, availability bias, and perception bias on the probability 
of making a sighting. These density models were originally developed 
for all cetacean taxa in the U.S. Atlantic (Roberts et al., 2016). In 
subsequent years, certain models have been updated on the basis of 
additional data as well as certain methodological improvements. The 
updated models incorporate additional sighting data, including 
sightings from the NOAA Atlantic Marine Assessment Program for 
Protected Species (AMAPPS) surveys from 2010-2014 (NEFSC & SEFSC, 2011, 
2012, 2014a, 2014b, 2015, 2016), and include updated density data for 
North Atlantic right whales, including in Cape Cod Bay (Roberts et al., 
2018). Our evaluation of the changes leads to a conclusion that these 
represent the best scientific evidence available. More information is 
available online at seamap.env.duke.edu/models/Duke-EC-GOM-2015/. 
Marine mammal density estimates in the project area (animals/km\2\) 
were obtained using these model results (Roberts et al., 2016, 2017, 
2018).
    For the exposure analysis, density data from the Duke University 
MGEL (Roberts et al. (2016, 2017, 2018)) were mapped using a geographic 
information system (GIS). The density coverages that included any 
portion of the proposed project area were selected for all potential 
survey months. For each of the survey areas (i.e., ECRA-1, ECRA-2, 
ECRA-3 and ECRA-4), the densities of each species as reported by the 
Duke University MGEL (Roberts et al. (2016, 2017, 2018)) were averaged 
by season; thus, a density was calculated for each species for spring, 
summer, fall and winter. To be conservative, the greatest seasonal 
density calculated for each species be carried forward in the exposure 
analysis. Estimated seasonal densities (animals per km\2\) of all 
marine mammal species that may be taken by the proposed surveys, for 
all seasons and all survey areas, are shown in Tables 6-2, 6-3, 6-4, 6-
5 and 6-6 of the IHA application. The maximum seasonal density values 
used to estimate marine mammal exposure numbers are shown in Table 6 
below. Note that Duke University MGEL density models do not 
differentiate by bottlenose dolphin stocks and instead provide 
estimates at the species level (Roberts et al. (2016, 2017, 2018)); the 
Western North Atlantic northern migratory coastal stock and the Western 
North Atlantic offshore stock of bottlenose dolphins may occur in the 
proposed survey areas (Hayes et al. 2018). Similarly, the Duke 
University MGEL produced density models for all seals and did not 
differentiate by seal species (Roberts et al. (2018)); harbor, gray and 
harp seals may occur in the proposed survey areas (Hayes et al. 2018).

Table 6--Seasonal Marine Mammal Densities (Number of Animals per 100 km\2\) in All Survey Areas Used in Exposure
                                                    Estimates
----------------------------------------------------------------------------------------------------------------
                 Species                       ECRA-1            ECRA-2            ECRA-3            ECRA-4
----------------------------------------------------------------------------------------------------------------
North Atlantic right whale..............         0.0063398        0.00192015         0.0002612         0.0008549
Humpback whale..........................         0.0054269        0.00147951         0.0003133         0.0007076
Fin whale...............................         0.0048318        0.00392609          0.000154         0.0029756

[[Page 37866]]

 
Sei whale...............................         0.0003972        0.00028884        0.00002179          0.000146
Minke whale.............................         0.0044061         0.0020292        0.00006959         0.0015375
Sperm Whale.............................         0.0001033        0.00029419        0.00004323         0.0003508
Pilot whales............................         0.0014728        0.00011263        0.00002895         0.0058357
Bottlenose dolphins.....................         0.0847306        0.02955662         0.0684936         0.0527685
Common dolphin..........................         0.0224355         0.2121851         0.0043119         0.1539656
Atlantic white-sided dolphin............          0.057509        0.05269613         0.0015548         0.0305044
Atlantic spotted dolphin................        0.00005057        0.00212995        0.00008059         0.0020008
Risso's dolphin.........................        0.00007374        0.00294218        0.00000215          0.000818
Harbor porpoise.........................           0.05438        0.07252193         0.1348293         0.0671625
Seals (all species).....................         0.3330293         0.0717368         0.0506316         0.0539549
----------------------------------------------------------------------------------------------------------------
Note: All density values derived from Roberts et al. (2016, 2017, 2018). Densities shown represent the maximum
  seasonal density values calculated, except pilot whales for which seasonal densities were not available.

Take Calculation and Estimates

    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    In order to estimate the number of marine mammals predicted to be 
exposed to sound levels that would result in harassment, radial 
distances to predicted isopleths corresponding to harassment thresholds 
are calculated, as described above. Those distances are then used to 
calculate the area(s) around the HRG survey equipment predicted to be 
ensonified to sound levels that exceed harassment thresholds. The area 
estimated to be ensonified to relevant thresholds in a single day is 
then calculated, based on areas predicted to be ensonified around the 
HRG survey equipment and the estimated trackline distance traveled per 
day by the survey vessel.
    Equinor estimates that proposed surveys will achieve a maximum 
daily track line distance of 177.6 km (110.3 mi) per day during 
proposed HRG surveys. We note that this is a conservative estimate as 
it accounts for the vessel traveling at approximately 4 knots and 
accounts for non-active survey periods (i.e., it assumes HRG equipment 
would be active 24 hours per day during all survey days when in fact 
there are likely to be periods when the equipment is not active). Based 
on the maximum estimated distance to the Level B harassment threshold 
of 141 m (Table 5) and the maximum estimated daily track line distance 
of 177.6 km (110.3 mi), an area of 50.08 km\2\ would be ensonified to 
the Level B harassment threshold per day during Equinor's proposed 
surveys. As stated above, this is a conservative assumption as there 
may be times during the proposed surveys when the GeoSource 800 J is 
not operated; if this were the case, the ensonified area would be much 
smaller, based on the modeled Level B harassment threshold associated 
with the USBL (Table 5).
    The number of marine mammals expected to be incidentally taken per 
day is then calculated by estimating the number of each species 
predicted to occur within the daily ensonified area (animals/km\2\), 
incorporating the estimated marine mammal densities as described above. 
Estimated numbers of each species taken per day are then multiplied by 
the total number of survey days. The product is then rounded, to 
generate an estimate of the total number of instances of harassment 
expected for each species over the duration of the survey. A summary of 
this method is illustrated in the following formula:

Estimated Take = D x ZOI x # of days

Where: D = average species density (per km\2\) and ZOI = maximum 
daily ensonified area to relevant thresholds.

    In this case, the methodology described above was used to estimate 
marine mammal exposures separately in the four ECRAs. Thus, exposures 
were calculated separately for each of the four individual ECRAs based 
on estimated survey duration in each ECRA (Table 2) and using the 
maximum seasonal density estimates for each respective ECRA (Table 6). 
Exposure estimates for the four survey areas were then combined for a 
total estimated number of exposures (Table 7).
    Though takes by Level B harassment of North Atlantic right whales 
were calculated based on the modeling approach described above, Equinor 
determined that take of the species could be avoided due to mitigation 
and therefore did not request take authorization for the North Atlantic 
right whale. However, given the size of modeled Level B harassment 
zone, the duration of the proposed surveys, and the fact that surveys 
will occur 24 hours per day, NMFS is not confident that all takes of 
right whales could be avoided due to mitigation, and we therefore 
propose to authorize 50 percent of the total number of exposures above 
the Level B harassment threshold that were modeled. We expect the 
proposed mitigation measures, including a 500-m exclusion zone for 
right whales (which exceeds the Level B harassment zone by over 350-m), 
will be effective in reducing the potential for takes by Level B 
harassment, but there is still a risk that right whales may not be 
detected within the Level B harassment zone during periods of 
diminished visibility, particularly at night. The numbers of takes 
proposed for authorization are shown in Table 7.

       Table 7--Numbers of Potential Incidental Take of Marine Mammals Proposed for Authorization and Proposed Takes as a Percentage of Population
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                          Total takes by  Total proposed
                                                             Estimated       Estimated       Estimated       Estimated        Level B      instances of
                         Species                          takes by Level  takes by Level  takes by Level  takes by Level    harassment       take as a
                                                           B harassment    B harassment    B harassment    B harassment    proposed for    percentage of
                                                              ECRA-1          ECRA-2          ECRA-3          ECRA-4       authorization  population \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale..............................               4               7               0               5               8             2.0

[[Page 37867]]

 
Humpback whale..........................................               3               5               1               4              13             0.8
Fin whale...............................................               3              14               0              19              36             0.8
Sei whale...............................................               1               1               0               1               3             0.4
Minke whale.............................................               3               7               0              10              20             0.9
Sperm Whale.............................................               0               1               0               2               3             0.1
Long-finned Pilot Whale.................................               1               1               0              37              39             0.2
Bottlenose dolphin \2\..................................              48             104              39             331             522             7.9
Common dolphin..........................................              13             747               2             966           1,728             2.0
Atlantic white-sided dolphin............................              33             185               1             191             410             1.1
Atlantic spotted dolphin................................               0               8               0              13              21             0.0
Risso's dolphin.........................................               0              10               0               5              15             0.2
Harbor porpoise.........................................              31             255              76             421             783             1.7
Seals \3\...............................................             188             253              29             338             808             1.1
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Calculations of percentage of stock taken are based on the best available abundance estimate as shown in Table 3. In most cases the best available
  abundance estimate is provided by Roberts et al. (2016, 2017, 2018), when available, to maintain consistency with density estimates derived from
  Roberts et al. (2016, 2017, 2018). For North Atlantic right whales the best available abundance estimate is derived from the North Atlantic Right
  Whale Consortium 2019 Annual Report Card (Pettis et al., 2019). For bottlenose dolphins and seals, Roberts et al. (2016, 2017, 2018) provides only a
  single abundance estimate and does not provide abundance estimates at the stock or species level (respectively), so abundance estimates used to
  estimate percentage of stock taken for bottlenose dolphins, gray, harbor and harp seals are derived from NMFS SARs (Hayes et al., 2019).
\2\ Either the Western North Atlantic coastal migratory stock or the Western North Atlantic offshore stock may be taken. Total proposed instances of
  take as a percentage of population shown for Western North Atlantic coastal migratory stock (based on all 522 proposed authorized takes accruing to
  that stock). The total proposed instances of take as a percentage of population for the Western North Atlantic offshore stock is 0.8 (based on all 522
  proposed authorized takes accruing to that stock).
\3\ Harbor, gray or harp seals may be taken. Total proposed instances of take as a percentage of population shown for harbor seals (based on all 808
  proposed authorized takes accruing to that species). The total proposed instances of take as a percentage of population for gray seals and harp seals
  is 0.2 and 0.0, respectively (based on all 808 proposed authorized takes accruing to each species).

    As described above, the Duke University MGEL produced density 
models that did not differentiate by seal species. The underlying data 
in the Duke University MGEL seal models came almost entirely from 
AMAPPS aerial surveys which were unable to differentiate by seal 
species, with the majority of seal sightings reported as ``unidentified 
seal'' (Roberts et al., 2018). Given the fact that the in-water 
habitats of harbor seals and gray seals are not well described but 
likely overlap, and based on the few species identifications that were 
available, the Duke University MGEL did not attempt to classify the 
ambiguous ``unidentified seal'' sightings by species (Roberts et al., 
2018) and instead produced models for seals as a guild. The take 
calculation methodology described above resulted in an estimate of 808 
total seal takes. Based on this estimate, Equinor requested 808 takes 
each of harbor, gray and harp seals, based on an assumption that the 
modeled takes could accrue to any of the respective species. We instead 
propose to authorize 808 total takes of seals by Level B harassment. 
Based on the occurrence of harbor, gray and harp seals in the survey 
areas, we expect the proposed authorized takes would accrue roughly 
equally to gray and harbor seals, with only a handful of takes of harp 
seals at most.
    The density models produced by the Duke University MGEL also did 
not differentiate by bottlenose dolphin stocks (Roberts et al. (2016, 
2017, 2018). The Western North Atlantic northern migratory coastal 
stock and the Western North Atlantic offshore stock occur in the 
proposed survey areas. The northern migratory coastal stock occurs in 
coastal waters from the shoreline to approximately the 20-m isobath 
while the offshore stock occurs at depths of 20-m and greater (Hayes et 
al. 2019). The take calculation methodology described above resulted in 
an estimate of 522 total bottlenose dolphin takes. Depths across the 
proposed survey areas range from very shallow waters near landfall 
locations to approximately 75-m in offshore survey locations. As 
proposed surveys would occur in areas where either the northern 
migratory coastal stock or the offshore stock may occur, we expect the 
proposed authorized takes would accrue roughly equally to both stocks.
    Equinor requested 39 total takes of pilot whales (either long-
finned or short-finned). However, the range of short-finned pilot 
whales does not extend north of Delaware (Hayes et al., 2019) and 
therefore short-finned pilot whales are not expected to occur in the 
proposed survey areas. As such, we propose to authorize takes of long-
finned pilot whales only.
    As described above, NMFS has determined that the likelihood of take 
of any marine mammals in the form of Level A harassment occurring as a 
result of the proposed surveys is so low as to be discountable; 
therefore, we do not propose to authorize take of any marine mammals by 
Level A harassment.

Proposed Mitigation

    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 such 
activity, and other means of effecting the least practicable impact on 
such species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of such 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 such 
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)).

[[Page 37868]]

    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 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 if implemented 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.

Proposed Mitigation Measures

    NMFS proposes the following mitigation measures be implemented 
during Equinor's proposed marine site characterization surveys.

Marine Mammal Exclusion Zones, Buffer Zone and Monitoring Zone

    Marine mammal exclusion zones (EZ) would be established around the 
HRG survey equipment and monitored by protected species observers (PSO) 
during HRG surveys as follows:
     A 500-m EZ would be required for North Atlantic right 
whales; and
     A 100-m EZ would be required for all other marine mammal 
species.
    If a marine mammal is detected approaching or entering the EZs 
during the proposed survey, the vessel operator would adhere to the 
shutdown procedures described below. In addition to the EZs described 
above, PSOs would visually monitor a 200 m Buffer Zone. During use of 
acoustic sources with the potential to result in marine mammal 
harassment (i.e., anytime the acoustic source is active, including 
ramp-up), occurrences of marine mammals within the Buffer Zone (but 
outside the EZs) would be communicated to the vessel operator to 
prepare for potential shutdown of the acoustic source. The Buffer Zone 
is not applicable when the EZ is greater than 100 meters. PSOs would 
also be required to observe a 500-m Monitoring Zone and record the 
presence of all marine mammals within this zone. The zones described 
above would be based upon the radial distance from the active equipment 
(rather than being based on distance from the vessel itself).

Visual Monitoring

    A minimum of one NMFS-approved PSO 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). Visual 
monitoring would begin no less than 30 minutes prior to ramp-up of HRG 
equipment and would continue until 30 minutes after use of the acoustic 
source ceases or until 30 minutes past sunset. PSOs would establish and 
monitor the applicable EZs, Buffer Zone and Monitoring Zone as 
described above. Visual PSOs would coordinate to ensure 360[deg] visual 
coverage around the vessel from the most appropriate observation posts, 
and would conduct visual observations using binoculars and the naked 
eye while free from distractions and in a consistent, systematic, and 
diligent manner. PSOs would estimate distances to observed marine 
mammals. It would be the responsibility of the Lead PSO on duty to 
communicate the presence of marine mammals as well as to communicate 
action(s) that are necessary to ensure mitigation and monitoring 
requirements are implemented as appropriate. Position data would be 
recorded using hand-held or vessel global positioning system (GPS) 
units for each confirmed marine mammal sighting.

Pre-Clearance of the Exclusion Zones

    Prior to initiating HRG survey activities, Equinor would implement 
a 30-minute pre-clearance period. During pre-clearance monitoring 
(i.e., before ramp-up of HRG equipment begins), the Buffer Zone would 
also act as an extension of the 100-m EZ in that observations of marine 
mammals within the 200-m Buffer Zone would also preclude HRG operations 
from beginning. During this period, PSOs would ensure that no marine 
mammals are observed within 200-m of the survey equipment (500-m in the 
case of North Atlantic right whales). HRG equipment would not start up 
until this 200-m zone (or, 500-m zone in the case of North Atlantic 
right whales) is clear of marine mammals for at least 30 minutes. The 
vessel operator would notify a designated PSO of the planned start of 
HRG survey equipment as agreed upon with the lead PSO; the notification 
time should not be less than 30 minutes prior to the planned initiation 
of HRG equipment order to allow the PSOs time to monitor the EZs and 
Buffer Zone for the 30 minutes of pre-clearance. A PSO conducting pre-
clearance observations would be notified again immediately prior to 
initiating active HRG sources.
    If a marine mammal were observed within the relevant EZs or Buffer 
Zone during the pre-clearance period, initiation of HRG survey 
equipment would not begin until the animal(s) has been observed exiting 
the respective EZ or Buffer Zone, or, until an additional time period 
has elapsed with no further sighting (i.e., minimum 15 minutes for 
small odontocetes and seals, and 30 minutes for all other species). The 
pre-clearance requirement would include small delphinoids that approach 
the vessel (e.g., bow ride). PSOs would also continue to monitor the 
zone for 30 minutes after survey equipment is shut down or survey 
activity has concluded. These requirements would be in effect only when 
the GeoSource 800 J sparker is being operated.

Ramp-Up of Survey Equipment

    When technically feasible, a ramp-up procedure would be used for 
geophysical survey equipment capable of adjusting energy levels at the 
start or re-start of survey activities. The ramp-up procedure would be 
used at the beginning of HRG survey activities in order to provide 
additional protection to marine mammals near the survey area by 
allowing them to detect the presence of the survey and vacate the area 
prior to the commencement of survey equipment operation at full power. 
Ramp-up of the survey equipment would not begin until the relevant EZs 
and Buffer Zone has been cleared by the PSOs, as described above. HRG 
equipment would be initiated at their lowest power output and would be 
incrementally increased to full power. If any marine mammals are 
detected within the EZs or Buffer Zone prior to or during ramp-up, the 
HRG equipment would be shut down (as described below).

Shutdown Procedures

    If an HRG source is active and a marine mammal is observed within 
or entering a relevant EZ (as described above) an immediate shutdown of 
the HRG survey equipment would be required. When shutdown is called for 
by a PSO, the acoustic source would be immediately deactivated and any 
dispute resolved only following deactivation. Any PSO on duty would 
have the authority to delay the start of survey operations or to call 
for shutdown of the acoustic source if a

[[Page 37869]]

marine mammal is detected within the applicable EZ. The vessel operator 
would establish and maintain clear lines of communication directly 
between PSOs on duty and crew controlling the HRG source(s) to ensure 
that shutdown commands are conveyed swiftly while allowing PSOs to 
maintain watch. Subsequent restart of the HRG equipment would only 
occur after the marine mammal has either been observed exiting the 
relevant EZ, or, until an additional time period has elapsed with no 
further sighting of the animal within the relevant EZ (i.e., 15 minutes 
for small odontocetes, pilot whales and seals, and 30 minutes for large 
whales).
    Upon implementation of shutdown, the HRG source may be reactivated 
after the marine mammal that triggered the shutdown has been observed 
exiting the applicable EZ (i.e., the animal is not required to fully 
exit the Buffer Zone where applicable), or, following a clearance 
period of 15 minutes for small odontocetes and seals and 30 minutes for 
all other species with no further observation of the marine mammal(s) 
within the relevant EZ. If the HRG equipment shuts down for brief 
periods (i.e., less than 30 minutes) for reasons other than mitigation 
(e.g., mechanical or electronic failure) the equipment may be re-
activated as soon as is practicable at full operational level, without 
30 minutes of pre-clearance, only if PSOs have maintained constant 
visual observation during the shutdown and no visual detections of 
marine mammals occurred within the applicable EZs and Buffer Zone 
during that time. For a shutdown of 30 minutes or longer, or if visual 
observation was not continued diligently during the pause, pre-
clearance observation is required, as described above.
    The shutdown requirement would be waived for certain genera of 
small delphinids (i.e., Delphinus, Lagenorhynchus, Stenella, and 
Tursiops) under certain circumstances. If a delphinid(s) from these 
genera is visually detected approaching the vessel (i.e., to bow ride) 
or towed survey equipment, shutdown would not be required. If there is 
uncertainty regarding identification of a marine mammal species (i.e., 
whether the observed marine mammal(s) belongs to one of the delphinid 
genera for which shutdown is waived), PSOs would use best professional 
judgment in making the decision to call for a shutdown.
    If a species for which authorization has not been granted, or, a 
species for which authorization has been granted but the authorized 
number of takes have been met, approaches or is observed within the 
area encompassing the Level B harassment isopleth while the sparker is 
operating (141 m), shutdown would occur.

Seasonal Restrictions

    To minimize the potential for impacts to North Atlantic right 
whales, vessel-based HRG survey activities would be prohibited in the 
Off Race Point SMA and Cape Cod Bay SMA from January through May and in 
the Great South Channel SMA from April through July.

Vessel Strike Avoidance

     Vessel strike avoidance measures would include, but would 
not be limited to, the following: Vessel operators and crews must 
maintain a vigilant watch for all protected species and slow down, stop 
their vessel, or alter course, as appropriate and regardless of vessel 
size, to avoid striking any protected species. A visual observer aboard 
the vessel must monitor a vessel strike avoidance zone around the 
vessel (distances stated below). Visual observers monitoring the vessel 
strike avoidance zone may be third-party observers (i.e., PSOs) or crew 
members, but crew members responsible for these duties must be provided 
sufficient training to (1) distinguish protected species from other 
phenomena and (2) broadly to identify a marine mammal as a right whale, 
other whale (defined in this context as sperm whales or baleen whales 
other than right whales), or other marine mammal.
     All survey vessels, regardless of size, must observe a 10-
knot speed restriction in specific areas designated by NMFS for the 
protection of North Atlantic right whales from vessel strikes: Any 
Dynamic Management Areas (DMAs) when in effect, and the Off Race Point 
SMA (in effect from January 1 through May 15), Cape Cod Bay SMA (in 
effect from March 1 through April 30), Great South Channel SMA (in 
effect from April 1 through July 31), Block Island Sound SMA (in effect 
from November 1 through April 30); and New York/New Jersey SMA (in 
effect from November 1 through April 30). See www.fisheries.noaa.gov/national/endangered-species-conservation/reducing-ship-strikes-north-atlantic-right-whales for specific detail regarding these areas.
     Vessel speeds must also be reduced to 10 knots or less 
when mother/calf pairs, pods, or large assemblages of cetaceans are 
observed near a vessel.
     All vessels must maintain a minimum separation distance of 
500 m from right whales. If a whale is observed but cannot be confirmed 
as a species other than a right whale, the vessel operator must assume 
that it is a right whale and take appropriate action.
     All vessels must maintain a minimum separation distance of 
100 m from sperm whales and all other baleen whales.
     All vessels must, to the maximum extent practicable, 
attempt to maintain a minimum separation distance of 50 m from all 
other protected species, with an understanding that at times this may 
not be possible (e.g., for animals that approach the vessel).
     When protected species are sighted while a vessel is 
underway, the vessel must take action as necessary to avoid violating 
the relevant separation distance (e.g., attempt to remain parallel to 
the animal's course, avoid excessive speed or abrupt changes in 
direction until the animal has left the area). If protected species are 
sighted within the relevant separation distance, the vessel must reduce 
speed and shift the engine to neutral, not engaging the engines until 
animals are clear of the area. This does not apply to any vessel towing 
gear or any vessel that is navigationally constrained.
    These requirements do not apply in any case where compliance would 
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.

Seasonal Operating Requirements

    As described above, the proposed survey area partially overlaps 
with a portion of five North Atlantic right whale SMAs: Off Race Point 
SMA (in effect from January 1 through May 15); Cape Cod Bay SMA (in 
effect from March 1 through April 30); Great South Channel SMA (in 
effect from April 1 through July 31); Block Island Sound SMA (in effect 
from November 1 through April 30); and New York/New Jersey SMA (in 
effect from November 1 through April 30). All Equinor survey vessels, 
regardless of length, would be required to adhere to vessel speed 
restrictions (<10 knots) when operating within the SMAs during times 
when the SMAs are in effect. In addition, between watch shifts, members 
of the monitoring team would consult NMFS's North Atlantic right whale 
reporting systems for the presence of North Atlantic right whales 
throughout survey operations. Members of the monitoring team would also 
monitor the NMFS North Atlantic right whale reporting systems for the 
establishment of DMA. If NMFS should establish a DMA in the survey area 
while surveys are underway, Equinor would be required to contact NMFS

[[Page 37870]]

within 24 hours of the establishment of the DMA to determine whether 
alteration or restriction of survey activities was warranted within the 
DMA to minimize impacts to right whales.
    Also as described above, portions of the proposed survey areas 
overlap spatially with designated critical habitat for North Atlantic 
right whales, which was established due to the area's significance for 
right whale foraging (81 FR 4837, January 27, 2016). To minimize 
potential impacts to right whales during the seasons when they occur in 
high numbers in the Gulf of Maine/Georges Bank critical habitat, 
vessel-based HRG survey activities would be prohibited in the Off Race 
Point SMA and Cape Cod Bay SMA from January through May and in the 
Great South Channel SMA from April through July.
    The proposed mitigation measures are designed to avoid the already 
low potential for injury in addition to some instances of Level B 
harassment, and to minimize the potential for vessel strikes. Further, 
we believe the proposed mitigation measures are practicable for the 
applicant to implement.
    There are no known marine mammal rookeries or mating or calving 
grounds in the survey area that would otherwise potentially warrant 
increased mitigation measures for marine mammals or their habitat (or 
both). The proposed survey areas would overlap spatially with an area 
that has been identified as a biologically important area for migration 
for North Atlantic right whales. However, while the potential survey 
areas across the ECRAs are relatively large, the actual areas that will 
ultimately be surveyed are relatively small compared to the 
substantially larger spatial extent of the right whale migratory area. 
We have proposed mitigation measures, including seasonal restrictions 
and vessel speed restrictions as described above, to minimize potential 
impacts to right whale migration. Thus, the survey is not expected to 
appreciably reduce migratory habitat nor to negatively impact the 
migration of North Atlantic right whales. As described above, some 
portions of the proposed survey areas would overlap spatially with 
areas that are recognized as important for North Atlantic right whale 
foraging, including portions of areas that have been designated as 
critical habitat due to the significance of the area for right whale 
foraging. We have proposed mitigation measures, including seasonal 
restrictions and vessel speed restrictions as described above, to 
minimize potential impacts to right whale foraging. Thus, the survey is 
not expected to appreciably reduce foraging habitat nor to negatively 
impact North Atlantic right whales foraging.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed 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.

Proposed 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 
proposed 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 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.

Proposed Monitoring Measures

    As described above, visual monitoring would be performed by 
qualified and NMFS-approved PSOs. Equinor would use independent, 
dedicated, trained PSOs, meaning that the PSOs must be employed by a 
third-party observer provider (with limited exceptions made only for 
inshore vessels), must have no tasks other than to conduct 
observational effort, collect data, and communicate with and instruct 
relevant vessel crew with regard to the presence of marine mammals and 
mitigation requirements (including brief alerts regarding maritime 
hazards), and must have successfully completed an approved PSO training 
course appropriate for their designated task. Equinor would provide 
resumes of all proposed PSOs (including alternates) to NMFS for review 
and approval prior to the start of survey operations.
    During survey operations (e.g., any day on which use of an HRG 
source is planned to occur), a minimum of one PSO must be on duty and 
conducting visual observations at all times on all active survey 
vessels during daylight hours (i.e., from 30 minutes prior to sunrise 
through 30 minutes following sunset). Visual monitoring would begin no 
less than 30 minutes prior to initiation of HRG survey equipment and 
would continue until one hour after use of the acoustic source ceases 
or until 30 minutes past sunset. PSOs would coordinate to ensure 360 
degree visual coverage around the vessel from the most appropriate 
observation posts, and would conduct visual observations using 
binoculars and the naked eye while free from distractions and in a 
consistent, systematic, and diligent manner. PSOs may be on watch for a 
maximum of four consecutive hours followed by a break of at least two 
hours between watches and may conduct a maximum of 12 hours of 
observation per 24-hour period. In cases where multiple vessels are 
surveying concurrently, any observations of marine mammals would be 
communicated to PSOs on all survey vessels.
    PSOs would be equipped with binoculars and have the ability to 
estimate distances to observed marine mammals. Reticulated binoculars 
will be available to PSOs for use as appropriate based on conditions 
and visibility to support the monitoring of

[[Page 37871]]

marine mammals. Position data would be recorded using hand-held or 
vessel GPS units for each sighting. Observations would take place from 
the highest available vantage point on the survey vessel. General 360-
degree scanning would occur during the monitoring periods, and target 
scanning by the PSO would occur when alerted of a marine mammal 
presence.
    During good conditions (e.g., daylight hours; Beaufort sea state 
(BSS) 3 or less), to the maximum extent practicable, PSOs would conduct 
observations when the acoustic source is not operating for comparison 
of sighting rates and behavior with and without use of the acoustic 
source and between acquisition periods. Any observations of marine 
mammals by crew members aboard any vessel associated with the survey 
would be relayed to the PSO team.
    Data on all PSO observations would be recorded based on standard 
PSO collection requirements. This would include dates, times, and 
locations of survey operations; dates and times of observations, 
location and weather; details of marine mammal sightings (e.g., 
species, numbers, behavior); and details of any observed marine mammal 
take that occurs (e.g., noted behavioral disturbances).

Proposed Reporting Measures

    Within 90 days after completion of survey activities, a final 
technical report will be provided to NMFS that fully documents the 
methods and monitoring protocols, summarizes the data recorded during 
monitoring, summarizes the number of marine mammals estimated to have 
been taken during survey activities (by species, when known), (i.e., 
observations of marine mammals within the Level B harassment zone must 
be reported as potential takes by Level B harassment) summarizes the 
mitigation actions taken during surveys (including what type of 
mitigation and the species and number of animals that prompted the 
mitigation action, when known), and provides an interpretation of the 
results and effectiveness of all mitigation and monitoring. Any 
recommendations made by NMFS must be addressed in the final report 
prior to acceptance by NMFS.
    In addition to the final technical report, Equinor will provide the 
reports described below as necessary during survey activities. In the 
event that personnel involved in the survey activities covered by the 
authorization discover an injured or dead marine mammal, Equinor must 
report the incident to the NOAA Fisheries Office of Protected Resources 
(OPR) (301-427-8401), and to the NOAA Fisheries New England/Mid-
Atlantic Regional Stranding Coordinator (978-282-8478) as soon as 
feasible. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.
    In the event of a vessel strike of a marine mammal by any vessel 
involved in the activities covered by the authorization, the Equinor 
must report the incident to NOAA Fisheries OPR (301-427-8401) and to 
the NOAA Fisheries New England/Mid-Atlantic Regional Stranding 
Coordinator (978-282-8478) as soon as feasible. The report must include 
the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Species identification (if known) or description of the 
animal(s) involved;
     Vessel's speed during and leading up to the incident;
     Vessel's course/heading and what operations were being 
conducted (if applicable);
     Status of all sound sources in use;
     Description of avoidance measures/requirements that were 
in place at the time of the strike and what additional measures were 
taken, if any, to avoid strike;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, visibility) immediately preceding the 
strike;
     Estimated size and length of animal that was struck;
     Description of the behavior of the marine mammal 
immediately preceding and following the strike;
     If available, description of the presence and behavior of 
any other marine mammals immediately preceding the strike;
     Estimated fate of the animal (e.g., dead, injured but 
alive, injured and moving, blood or tissue observed in the water, 
status unknown, disappeared); and
     To the extent practicable, photographs or video footage of 
the animal(s).

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 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 7, given that NMFS expects the anticipated effects of the 
proposed survey to be similar in nature. To be conservative, our 
analyses assume that a total of 808 exposures above the Level B 
harassment threshold could accrue to all of the potentially impacted 
seal species (i.e., harbor, gray and harp seals), and that a total of 
522 exposures above the Level B harassment threshold could accrue to 
both bottlenose dolphin stocks that may be present (i.e., the Western 
North Atlantic offshore stock and the Western North Atlantic northern 
coastal migratory stock).
    NMFS does not anticipate that serious injury or mortality would 
occur as a result of Equinor's proposed survey, even in the absence of 
proposed mitigation, thus the proposed authorization does not authorize 
any serious injury or mortality. As discussed in the Potential Effects 
of Specified Activities on Marine Mammals and their

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Habitat section, non-auditory physical effects and vessel strike are 
not expected to occur. Additionally and as discussed previously, given 
the nature of activity and sounds sources used and especially in 
consideration of the required mitigation, Level A harassment is neither 
anticipated nor authorized. We expect that all potential takes would be 
in the form of short-term Level B behavioral harassment in the form of 
temporary avoidance of the area, reactions that are considered to be of 
low severity and with no lasting biological consequences (e.g., 
Southall et al., 2007).
    Effects on individuals that are taken by Level B harassment, on the 
basis of reports in the literature as well as monitoring from other 
similar activities, will likely be limited to reactions such as 
increased swimming speeds, increased surfacing time, or decreased 
foraging (if such activity were occurring). Most likely, individuals 
will simply move away from the sound source and temporarily avoid the 
area where the survey is occurring. We expect that any avoidance of the 
survey area by marine mammals would be temporary in nature and that any 
marine mammals that avoid the survey area during the survey activities 
would not be permanently displaced. Even repeated Level B harassment of 
some small subset of an overall stock is unlikely to result in any 
significant realized decrease in viability for the affected 
individuals, and thus would not result in any adverse impact to the 
stock as a whole. Instances of more severe behavioral harassment are 
expected to be minimized by proposed mitigation and monitoring 
measures.
    In addition to being temporary and short in overall duration, the 
acoustic footprint of the proposed survey is small relative to the 
overall distribution of the animals in the area and their use of the 
area. Feeding behavior is not likely to be significantly impacted. 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 
and the availability of similar habitat and resources in the 
surrounding area, 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.
    There are no rookeries, mating or calving grounds known to be 
biologically important to marine mammals within the proposed survey 
area. As described above, the proposed survey areas overlap spatially 
with a biologically important migratory area for North Atlantic right 
whales (effective March-April and November-December) that extends from 
Massachusetts to Florida (LaBrecque, et al., 2015). Off the coasts of 
Massachusetts, Rhode Island, Connecticut, New York and New Jersey, this 
biologically important migratory area extends from the coast to beyond 
the shelf break. Due to the fact that that the proposed survey is 
temporary and the spatial extent of sound produced by the survey would 
be very small relative to the spatial extent of the available migratory 
habitat in the area, and due to proposed mitigation measures including 
seasonal restrictions, right whale migration is not expected to be 
impacted by the proposed survey. As described above, some portions of 
the proposed survey areas overlap spatially with areas that are 
recognized as important for North Atlantic right whale foraging, 
including portions of areas that have been designated as ESA critical 
habitat due to the significance of the area for right whale feeding. 
Due to the fact that that the proposed survey is temporary and the 
spatial extent of sound produced by the survey would very small 
relative to the spatial extent of the available foraging habitat in the 
area, as well as proposed mitigation measures including seasonal 
restrictions in areas and seasons when right whale foraging is 
predicted to occur, North Atlantic right whale foraging is not expected 
to be impacted by the proposed surveys.
    As described above, North Atlantic right, humpback, and minke 
whales, and gray, harbor and harp seals are experiencing ongoing UMEs. 
For North Atlantic right whales, as described above, no injury as a 
result of the proposed project is expected or proposed for 
authorization, and Level B harassment takes of right whales are 
expected to be in the form of avoidance of the immediate area of the 
proposed survey. In addition, the number of takes proposed for 
authorization above the Level B harassment threshold are relatively low 
(i.e., 8), and the take numbers proposed for authorization do not 
account for the proposed mitigation measures, which would require 
shutdown of all survey equipment upon observation of a right whale 
prior to their entering the zone that would be ensonified above the 
Level B harassment threshold. As no injury or mortality is expected or 
proposed for authorization, and Level B harassment of North Atlantic 
right whales will be reduced to the level of least practicable adverse 
impact through use of proposed mitigation measures, the proposed 
authorized takes of right whales would not exacerbate or compound the 
ongoing UME in any way.
    Similarly, no injury or mortality is expected or proposed for 
authorization for any of the other species with UMEs, Level B 
harassment will be reduced to the level of least practicable adverse 
impact through use of proposed mitigation measures, and the proposed 
authorized takes would not exacerbate or compound the ongoing UMEs. For 
minke whales, although the ongoing UME is under investigation (as 
occurs for all UMEs), this event does not provide cause for concern 
regarding population level impacts, as the likely population abundance 
is greater than 20,000 whales and annual M/SI does not exceed the 
calculated PBR value for minke whales. With regard to humpback whales, 
the UME does not yet provide cause for concern regarding population-
level impacts. Despite the UME, the relevant population of humpback 
whales (the West Indies breeding population, or DPS) remains healthy. 
The West Indies DPS, which consists of the whales whose breeding range 
includes the Atlantic margin of the Antilles from Cuba to northern 
Venezuela, and whose feeding range primarily includes the Gulf of 
Maine, eastern Canada, and western Greenland is not listed under the 
ESA. The status review identified harmful algal blooms, vessel 
collisions, and fishing gear entanglements as relevant threats for this 
DPS, but noted that all other threats are considered likely to have no 
or minor impact on population size or the growth rate of this DPS 
(Bettridge et al., 2015). As described in Bettridge et al., (2015), the 
West Indies DPS has a substantial population size (i.e., approximately 
10,000; Stevick et al., 2003; Smith et al., 1999; Bettridge et al., 
2015), and appears to be experiencing consistent growth. With regard to 
gray, harbor and harp seals, although the ongoing UME is under 
investigation, the UME does not yet provide cause for concern regarding 
population-level impacts to any of these stocks. For harbor seals, the 
population abundance is over 75,000 and annual M/SI (345) is well below 
PBR (2,006) (Hayes et al., 2019). For gray seals, the population 
abundance in the United States is over 27,000, with an estimated 
abundance including seals in Canada of approximately 505,000, and 
abundance is likely increasing in the U.S. Atlantic EEZ as well as in 
Canada (Hayes et al.,

[[Page 37873]]

2019). For harp seals, while PBR is unknown, the minimum population 
estimate is 6.9 million and the population appears to be stable (Hayes 
et al., 2019).
    The proposed mitigation measures are expected to reduce the number 
and/or severity of takes by (1) giving animals the opportunity to move 
away from the sound source before HRG survey equipment reaches full 
energy; (2) preventing animals from being exposed to sound levels that 
may otherwise result in injury or more severe behavioral responses. 
Additional vessel strike avoidance requirements will further mitigate 
potential impacts to marine mammals during vessel transit to and within 
the survey area.
    NMFS concludes that exposures to marine mammal species and stocks 
due to Equinor's proposed survey would result in only short-term 
(temporary and short in duration) effects to individuals exposed. 
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 proposed take estimates to impact annual rates of 
recruitment or survival.
    In summary and as described above, the following factors primarily 
support our preliminary 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, serious injury, or Level A harassment is 
anticipated or authorized;
     The anticipated impacts of the proposed activity on marine 
mammals would primarily be in the form of temporary behavioral changes 
due to avoidance of the area around the survey vessel;
     The availability of alternate areas of similar habitat 
value (for foraging and migration) for marine mammals that may 
temporarily vacate the survey areas during the proposed surveys to 
avoid exposure to sounds from the activity;
     The proposed project area does not contain known areas of 
significance for mating or calving;
     Effects on species that serve as prey species for marine 
mammals from the proposed survey would be minor and temporary and would 
not be expected to reduce the availability of prey or to affect marine 
mammal feeding;
     The proposed mitigation measures, including visual 
monitoring, exclusion zones, and shutdown measures, 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 proposed monitoring and 
mitigation measures, NMFS preliminarily 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. When the predicted number of 
individuals to be taken is less than one third of the species or stock 
abundance, the take is considered to be of small numbers. Additionally, 
other qualitative factors may be considered in the analysis, such as 
the temporal or spatial scale of the activities.
    We propose to authorize incidental take of 17 marine mammal stocks. 
The total amount of taking proposed for authorization is less than one 
third for all stocks (Table 7), which we preliminarily find are small 
numbers of marine mammals relative to the estimated overall population 
abundances for those stocks. To be conservative, our small numbers 
analysis assumes a total of 808 exposures above the Level B harassment 
threshold could accrue to any of the potentially impacted seal species 
(i.e., harbor, gray or harp seals) and a total of 522 exposures above 
the Level B harassment threshold could accrue to both bottlenose 
dolphin stocks that may be present (i.e., the Western North Atlantic 
offshore stock and the Western North Atlantic northern coastal 
migratory stock). Based on the analysis contained herein of the 
proposed activity (including the proposed mitigation and monitoring 
measures) and the anticipated take of marine mammals, NMFS 
preliminarily finds that small numbers of marine mammals will be taken 
relative to the population size of all 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 would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act

    Section 7(a)(2) of the Endangered Species Act of 1973 (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 NMFS Greater Atlantic 
Regional Fisheries Office (GARFO), whenever we propose to authorize 
take for endangered or threatened species.
    The NMFS OPR is proposing to authorize the incidental take of four 
species of marine mammals which are listed under the ESA: The North 
Atlantic right, fin, sei, and sperm whale. The NMFS OPR has requested 
initiation of Section 7 consultation with NMFS GARFO for the issuance 
of this IHA. NMFS will conclude the ESA section 7 consultation prior to 
reaching a determination regarding the issuance of the authorization.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to Equinor for conducting marine site characterization 
activities offshore of Massachusetts, Rhode Island, Connecticut, New 
York and New Jersey for a period of one year, provided the previously 
mentioned mitigation, monitoring, and reporting requirements are 
incorporated. A draft of the proposed IHA can be found at: 
www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for Equinor's proposed 
activity. We also request at this time comment on the potential Renewal 
of this proposed IHA as described in the paragraph below. Please 
include with your comments any supporting data or literature citations 
to

[[Page 37874]]

help inform decisions on the request for this IHA or a subsequent 
Renewal IHA.
    On a case-by-case basis, NMFS may issue a one time, one-year 
Renewal IHA following notice to the public providing an additional 15 
days for public comments when (1) up to another year of identical or 
nearly identical, or nearly identical, activities as described in the 
Specified Activities section of this notice is planned or (2) the 
activities as described in the Specified Activities section of this 
notice would not be completed by the time the IHA expires and a Renewal 
would allow for completion of the activities beyond that described in 
the Dates and Duration section of this notice, provided all of the 
following conditions are met:
     A request for renewal is received no later than 60 days 
prior to the needed Renewal IHA effective date (recognizing that the 
Renewal IHA expiration date cannot extend beyond one year from 
expiration of the initial IHA).
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested Renewal IHA are identical to the activities analyzed under 
the initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take).
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
     Upon review of the request for Renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: June 16, 2020.
Donna Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2020-13605 Filed 6-23-20; 8:45 am]
BILLING CODE 3510-22-P