Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Marine Site Characterization Surveys Off of Rhode Island and Massachusetts, 19711-19736 [2018-09481]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 83, Number 87 (Friday, May 4, 2018)]
[Notices]
[Pages 19711-19736]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-09481]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF984


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Marine Site Characterization 
Surveys Off of Rhode Island and Massachusetts

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments.

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SUMMARY: NMFS has received a request from Deepwater Wind New England, 
LLC (DWW), for authorization to take marine mammals incidental to 
marine site characterization surveys off the coast of Rhode Island and 
Massachusetts in the area of the Commercial Lease of Submerged Lands 
for Renewable Energy Development on the Outer Continental Shelf (OCS-A 
0486) and along potential submarine cable routes to a landfall location 
in Rhode Island, Massachusetts or New York. 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 
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 June 4, 
2018.

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. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. 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: Jordan Carduner, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the applications 
and 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

    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 
authorization is provided to the public for review.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for subsistence uses (where 
relevant), and if the permissible methods of taking and requirements 
pertaining to the mitigation, monitoring and reporting of such takings 
are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as an 
impact resulting from the specified activity that cannot be reasonably 
expected to, and is not reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.

[[Page 19712]]

    The MMPA states that the term ``take'' means to harass, hunt, 
capture, or kill, or attempt to harass, hunt, capture, or kill any 
marine mammal.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering (Level B harassment).

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    Accordingly, NMFS is preparing an Environmental Assessment (EA) to 
consider the environmental impacts associated with the issuance of the 
proposed IHA. We will review all comments submitted in response to this 
notice prior to concluding our NEPA process or making a final decision 
on the IHA request.

Summary of Request

    On January 3, 2018, NMFS received a request from DWW for an IHA to 
take marine mammals incidental to marine site characterization surveys 
off the coast of Massachusetts and Rhode Island in the area of the 
Commercial Lease of Submerged Lands for Renewable Energy Development on 
the Outer Continental Shelf (OCS-A 0486) and along potential submarine 
cable routes to a landfall location in either Rhode Island, 
Massachusetts or New York. A revised application was received on April 
18, 2018. NMFS deemed that request to be adequate and complete. DWW's 
request is for take of 14 marine mammal species by Level B harassment. 
Neither DWW 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

    DWW proposes to conduct marine site characterization surveys, 
including high-resolution geophysical (HRG) and geotechnical surveys, 
in the area of Commercial Lease of Submerged Lands for Renewable Energy 
Development on the Outer Continental Shelf #OCS-A 0486 (Lease Area) and 
along potential submarine cable routes to landfall locations in either 
Rhode Island, Massachusetts or Long Island, New York. Surveys would 
occur from approximately June 15, 2018 through December 31, 2018.
    The purpose of the marine site characterization surveys are to 
obtain a baseline assessment of seabed/sub-surface soil conditions in 
the Lease Area and cable route corridors to support the siting of 
potential future offshore wind projects. Underwater sound resulting 
from DWW's proposed site characterization surveys has the potential to 
result in incidental take of marine mammals in the form of behavioral 
harassment.

Dates and Duration

    The estimated duration of the geophysical survey is expected to be 
up to 200 days between June 15, 2018, and December 31, 2018. The 
geotechnical surveys are expected to take up to 100 days between June 
15, 2018, and December 31, 2018. This schedule is based on 24-hour 
operations and includes potential down time due to inclement weather. 
Surveys will last for approximately seven months and are anticipated to 
commence upon issuance of the requested IHA, if appropriate.

Specific Geographic Region

    DWW's survey activities would occur in the Northwest Atlantic Ocean 
within Federal waters. Surveys would occur in the Lease Area and along 
potential submarine cable routes to landfall locations in either Rhode 
Island, Massachusetts or Long Island, New York (see Figure 1 in the IHA 
application). The Lease Area is approximately 394 square kilometers 
(km\2\) (97,498 acres) and is approximately 20 km south of Rhode Island 
at its closest point to land.

Detailed Description of the Specified Activities

    DWW's proposed marine site characterization surveys include HRG and 
geotechnical survey activities. Surveys would occur within the Bureau 
of Ocean Energy Management (BOEM) Rhode Island-Massachusetts Wind 
Energy Area (RI-MA WEA) which is east of Long Island, New York and 
south of Rhode Island and Massachusetts (see Figure 1 in the IHA 
application). Water depths in the Lease Area range from 26 to 48 meters 
(m) (85 to 157 feet (ft)). For the purpose of this IHA the Lease Area 
and submarine cable corridor are collectively termed the Project Area.
    Geophysical and shallow geotechnical survey activities are 
anticipated to be supported by a vessel approximately 20-70 m long 
which will maintain a speed of up to five knots (kn) while transiting 
survey lines. Near shore geophysical and shallow geotechnical surveys 
(if required) would be performed by shallow draft vessels approximately 
9 to 23 m long which will maintain a speed of up to five kn while 
transiting survey lines. Deep geotechnical survey activities and 
possible shallow geotechnical activities are anticipated to be 
conducted from a 40 to 100 m dynamically positioned (DP) vessel, jack-
up vessel, or anchored vessel, with support of a tug boat. Survey 
activities will be executed in compliance with the July 2015 BOEM 
Guidelines for Providing Geophysical, Geotechnical, and Geohazard 
Information Pursuant to 30 CFR part 585. The proposed HRG and 
geotechnical survey activities are described below.

Geotechnical Survey Activities

    DWW's proposed geotechnical survey activities would include the 
following:
     Vibracores to characterize the geological and geotechnical 
characteristics of the seabed, up to approximately 5 m deep. A 
hydraulic or electric driven pulsating head is used to drive a hollow 
tube into the seafloor and recover a stratified representation of the 
sediment.
     Core Penetration Testing (CPT) to determine stratigraphy 
and in-situ conditions of the sediments. Target penetration is 60 to 75 
m.
     Deep Boring Cores would be drilled to determine the 
vertical and lateral variation in seabed conditions and provide 
geotechnical data to depths at least 10 m deeper than design 
penetration of the foundations (60 to 75 m target penetration).
    Shallow geotechnical surveys, consisting of CPTs and vibracores, 
are planned for within the Lease Area and approximately every one to 
two kilometers (km) along the export cable routes. Foundation-depth 
geotechnical borings are also planned at each proposed foundation 
location within the Lease Area. While the quantity and locations of 
wind turbine generators to be installed, as well as cable route, has 
yet to be determined, an estimate of 153 vibracores, 20 CPTs, and 16 
deep borings are planned within the Lease Area and along the export 
cable routes.
    In considering whether marine mammal harassment is an expected 
outcome of exposure to a particular

[[Page 19713]]

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. Monitoring of past projects that entailed use of DP 
thrusters has shown a lack of observed marine mammal responses as a 
result of exposure to sound from DP thrusters. 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.
    Vibracoring entails driving a hydraulic or electric pulsating head 
through a hollow tube into the seafloor to recover a stratified 
representation of the sediment. The vibracoring process is short in 
duration and is performed from a dynamic positioning vessel. The vessel 
would use DP thrusters to maintain the vessel's position while the 
vibracore sample is taken, as described above. The vibracoring process 
would always be performed in concert with DP thrusters, and DP 
thrusters would begin operating prior to the activation of the 
vibracore to maintain the vessel's position; thus, we expect that any 
marine mammals in the project area would detect the presence and noise 
associated with the vessel and the DP thrusters prior to commencement 
of vibracoring. Any reaction by marine mammals would be expected to be 
similar to reactions to the concurrent DP thrusters, which are expected 
to be minor and short term, i.e., not constituting Level B harassment, 
as defined by the MMPA. In this case, vibracoring is not planned in any 
areas of particular biological significance for any marine mammals. 
Thus while a marine mammal may perceive noise from vibracoring and may 
respond briefly, we believe the potential for this response to rise to 
the level of take to be so low as to be discountable, based on the 
short duration of the activity and the fact that marine mammals would 
be expected to react to the vessel and DP thrusters before vibracoring 
commences, potentially through brief avoidance. In addition, the fact 
that the geographic area is not biologically important for any marine 
mammal species means that such reactions are not likely to carry any 
meaningful significance for the animals.
    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 CPTs 
and boring cores, 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, including CPTs, boring cores and 
vibracores, are not expected to result in harassment of marine mammals 
and are not analyzed further in this document.

Geophysical Survey Activities

    DWW has proposed that HRG survey operations would be conducted 
continuously 24 hours per day. Based on 24-hour operations, the 
estimated duration of the geophysical survey activities would be 
approximately 200 days (including estimated weather down time). The 
geophysical survey activities proposed by DWW would include the 
following:
     Multibeam Depth Sounder to determine water depths and 
general bottom topography. The multibeam echosounder sonar system 
projects sonar pulses in several angled beams from a transducer mounted 
to a ship's hull. The beams radiate out from the transducer in a fan-
shaped pattern orthogonally to the ship's direction.
     Shallow Penetration Sub-Bottom Profiler (Chirp) to map the 
near surface stratigraphy (top 0 to 5 m of sediment below seabed). A 
Chirp system emits sonar pulses which increase in frequency (3.5 to 200 
kHz) over time. The pulse length frequency range can be adjusted to 
meet project variables.
     Medium Penetration Sub-Bottom Profiler (Boomer) to map 
deeper subsurface stratigraphy as needed. This system is commonly 
mounted on a sled and towed behind a boat.
     Medium Penetration Sub-Bottom Profiler (Sparker and/or 
bubble gun) to map deeper subsurface stratigraphy as needed. Sparkers 
create acoustic pulses omni-directionally from the source that can 
penetrate several hundred meters into the seafloor. Hydrophone arrays 
towed nearby receive the return signals.
     Sidescan Sonar used to image the seafloor for seabed 
sediment classification purposes and to identify natural and man-made 
acoustic targets on the seafloor. The 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 is recorded in a series of cross-track 
slices, which can be joined to form an image of the sea bottom within 
the swath of the beam.
     Marine Magnetometer to detect ferrous metal objects on the 
seafloor which may cause a hazard including anchors, chains, cables, 
pipelines, ballast stones and other scattered shipwreck debris, 
munitions of all sizes, unexploded ordinances, aircraft, engines and 
any other object with magnetic expression.
    Table 1 identifies the representative survey equipment that may be 
used in support of planned geophysical survey activities. The make and 
model of the listed geophysical equipment will vary depending on 
availability and the final equipment choices will vary depending upon 
the final survey design, vessel availability, and survey contractor 
selection. Geophysical surveys are expected to use several equipment 
types concurrently in order to collect multiple aspects of geophysical 
data along one transect. Selection of equipment combinations is based 
on specific survey objectives. Any survey equipment selected would have 
characteristics similar to the systems described below, if different.

[[Page 19714]]



                                                            Table 1--Summary of Geophysical Survey Equipment Proposed for Use by DWW
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                                                                      Source level  (SLrms dB re 1     Operational  depth (meters                                          Pulse duration
           Equipment type             Operating  frequencies  (kHz)           [mu]PA @1 m)                   below surface)             Beam width  (degrees)              (milliseconds)
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                                                                                    Multibeam Depth Sounding
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Reson SeaBat 7125 \1\..............  200 and 400...................  220...........................  4............................  128..........................  0.03 to 0.3.
Reson SeaBat 7101 \2\..............  100...........................  162...........................  2 to 5.......................  140..........................  0.8 to 3.04.
R2SONIC Sonic 2020 \1\.............  170 to 450....................  162...........................  2 to 5.......................  160..........................  0.11.
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                                                                                  Shallow Sub-bottom Profiling
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Teledyne Benthos Chirp III \3\.....  2 to 7........................  197...........................  4............................  45...........................  0.2.
EdgeTech SB3200 XS.................  2 to 16.......................  176...........................  2 to 5.......................  170..........................  3.4.
SB216 \4\..........................
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                                                                             Medium Penetration Sub-bottom Profiling
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Applied Acoustics..................  0.1 to 10.....................  175...........................  1 to 2.......................  60...........................  58.
Fugro boomer \1\...................
Applied Acoustics..................  0.25 to 8.....................  203...........................  2............................  25 to 35.....................  0.6.
S-Boom system--CSP-D 2400HV........
(600 joule/pulse) \5\..............
GeoResources 800 Joule Sparker \6\.  0.75 to 2.75..................  203...........................  4............................  360 (omni-directional).......  0.1 to 0.2.
Falmouth Scientific HMS 620 bubble   0.02 to 1.7...................  196...........................  1.5..........................  360 (omni-directional).......  1.6.
 gun \7\.
Applied Acoustics..................  0.03 to 5.....................  213...........................  1 to 2.......................  170..........................  2.1.
Dura-Spark 240 \5\.................
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                                                                                         Side Scan Sonar
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Klein Marine Systems model 3900 \1\  445 and 900...................  242...........................  20...........................  40...........................  0.025.
EdgeTech model 4125 \1\............  105 and 410...................  225...........................  10...........................  158..........................  10 to 20.
EdgeTech model 4200 \1\............  300 and 600...................  215 to 220....................  1............................  0.5 and 0.26.................  5 to 12.
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\1\ Source level obtained from equipment specifications as described in 2017 IHA issued to DWW for takes of marine mammals incidental to site characterization surveys off the coast of New York
  (82 FR 22250).
\2\ Source level based on published manufacturer specifications and/or systems manual.
\3\ Source level based on published manufacturer specifications and/or systems manual--assumed configured as TTV-171 with AT-471 transducer per system manual.
\4\ Source level obtained from Crocker and Fratantonio (2016). Assumed to be 3200 XS with SB216. Used as proxy: 3200 XS with SB424 in 4-24 kHz mode Since the 3200 XS system manual lists same
  power output between SB216 and SB 424.
\5\ Source level obtained from Crocker and Fratantonio (2016).
\6\ Source level obtained from Crocker and Fratantonio (2016)--ELC820 used as proxy.
\7\ Source level obtained from Crocker and Fratantonio (2016)--Used single plate 1 due to discrepancies noted in Crocker and Fratantonio (2016) regarding plate 2.

    The deployment of HRG survey equipment, including the equipment 
planned for use during DWW's planned activity, produces sound in the 
marine environment that has the potential to result in harassment of 
marine mammals. However, sound propagation is dependent on several 
factors including operating mode, frequency and beam direction of the 
HRG 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) were analyzed to determine which types 
of equipment would have the potential to result in harassment of marine 
mammals. HRG equipment that would be operated either at frequency 
ranges that fall outside the functional hearing ranges of marine 
mammals (e.g., above 200 kHz) or that operate within marine mammal 
functional hearing ranges but have low sound source levels (e.g., a 
single pulse at less than 200 dB re re 1 [mu]Pa) were assumed to not 
have the potential to result in marine mammal harassment and were 
therefore eliminated from further analysis. Of the potential HRG survey 
equipment planned for use, the following equipment was determined to 
have the potential to result in harassment of marine mammals:
     Teledyne Benthos Chirp III Sub-bottom Profiler;
     EdgeTech Sub-bottom Profilers (Chirp);
     Applied Acoustics Fugro Sub-bottom Profiler (Boomer);
     Applied Acoustics S-Boom Sub-bottom Profiling System 
consisting of a CSP-D 2400HV power supply and 3-plate catamaran;
     GeoResources 800 Joule Sparker;
     Falmouth Scientific HMS 620 Bubble Gun; and
     Applied Acoustics Dura-Spark 240 System.
    As the HRG survey equipment listed above was determined to have the 
potential to result in harassment of marine mammals, the equipment 
listed above was carried forward in the analysis of potential impacts 
to marine mammals; all other HRG equipment planned for use by DWW is 
not expected to result in harassment of marine mammals and is therefore 
not analyzed further in this document.
    Proposed mitigation, monitoring, and reporting measures are 
described in

[[Page 19715]]

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 DWW's IHA application summarize available 
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 (SAR; www.nmfs.noaa.gov/pr/sars/) and more general information about these species (e.g., 
physical and behavioral descriptions) may be found on NMFS' website 
(www.nmfs.noaa.gov/pr/species/mammals/). All species that could 
potentially occur in the proposed survey areas are included in Table 5 
of the IHA application. However, the temporal and/or spatial occurrence 
of several species listed in Table 5 of the IHA application is such 
that take of these species is not expected to occur, and they are not 
discussed further beyond the explanation provided here. Take of these 
species is not anticipated either because they have very low densities 
in the project area, are known to occur further offshore than the 
project area, or are considered very unlikely to occur in the project 
area during the proposed survey due to the species' seasonal occurrence 
in the area.
    Table 2 lists all species with expected potential for occurrence in 
the survey area and with the potential to be taken as a result of the 
proposed survey and summarizes information related to the population or 
stock, including regulatory status under the MMPA and ESA and potential 
biological removal (PBR), where known. For taxonomy, we follow 
Committee on Taxonomy (2017). 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 (e.g., Hayes et al., 2018). All values 
presented in Table 2 are the most recent available at the time of 
publication and are available in the 2017 draft Atlantic SARs (Hayes et 
al., 2018).

                                                Table 2--Marine Mammals Known To Occur in the Survey Area
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                                                                NMFS  MMPA  and       Stock abundance
                                                                  ESA  status;     (CV,Nmin, most recent     Predicted      PBR       Occurrence  and
             Common name                       Stock            strategic  (Y/N)   abundance survey) \2\     abundance      \4\     seasonality  in the
                                                                      \1\                                    (CV) \3\                   survey area
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                                                               Toothed whales (Odontoceti)
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Sperm whale (Physeter macrocephalus)  North Atlantic.........  E; Y               2,288 (0.28; 1,815; n/    5,353 (0.12)     3.6  Rare.
                                                                                   a).
Long-finned pilot whale               W North Atlantic.......  -; Y               5,636 (0.63; 3,464; n/      \5\ 18,977      35  Rare.
 (Globicephala melas).                                                             a).                            (0.11)
Atlantic white-sided dolphin          W North Atlantic.......  -; N               48,819 (0.61; 30,403;    37,180 (0.07)     304  Rare.
 (Lagenorhynchus acutus).                                                          n/a).
Atlantic spotted dolphin (Stenella    W North Atlantic.......  -; N               44,715 (0.43; 31,610;    55,436 (0.32)     316  Rare.
 frontalis).                                                                       n/a).
Bottlenose dolphin (Tursiops          W North Atlantic,        -; N               77,532 (0.40; 56,053;       \5\ 97,476     561  Common year round.
 truncatus).                           Offshore.                                   2011).                         (0.06)
Common dolphin \6\ (Delphinus         W North Atlantic.......  -; N               173,486 (0.55; 55,690;   86,098 (0.12)     557  Common year round.
 delphis).                                                                         2011).
Harbor porpoise (Phocoena phocoena).  Gulf of Maine/Bay of     -; N               79,833 (0.32; 61,415;         * 45,089     706  Common year round.
                                       Fundy.                                      2011).                         (0.12)
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                                                                Baleen whales (Mysticeti)
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale            W North Atlantic.......  E; Y               458 (0; 455; n/a).....    * 535 (0.45)     1.4  Year round in
 (Eubalaena glacialis).                                                                                                            continental shelf and
                                                                                                                                   slope waters, occur
                                                                                                                                   seasonally to forage.
Humpback whale \7\ (Megaptera         Gulf of Maine..........  -; N               823 (0.42; 239; n/a)..  * 1,637 (0.07)     3.7  Common year round.
 novaeangliae).
Fin whale \6\ (Balaenoptera           W North Atlantic.......  E; Y               3,522 (0.27; 1,234; n/    4,633 (0.08)     2.5  Year round in
 physalus).                                                                        a).                                             continental shelf and
                                                                                                                                   slope waters, occur
                                                                                                                                   seasonally to forage.
Sei whale (Balaenoptera borealis)...  Nova Scotia............  E; Y               357 (0.52; 236; n/a)..    * 717 (0.30)     0.5  Year round in
                                                                                                                                   continental shelf and
                                                                                                                                   slope waters, occur
                                                                                                                                   seasonally to forage.
Minke whale \6\ (Balaenoptera         Canadian East Coast....  -; N               20,741 (0.3; 1,425; n/  * 2,112 (0.05)     162  Year round in
 acutorostrata).                                                                   a).                                             continental shelf and
                                                                                                                                   slope waters, occur
                                                                                                                                   seasonally to forage.
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                                                                Earless seals (Phocidae)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Gray seal \8\ (Halichoerus grypus)..  W North Atlantic.......  -; N               27,131 (0.10; 25,908;   ..............   1,554  Rare.
                                                                                   n/a).
Harbor seal (Phoca vitulina)........  W North Atlantic.......  -; N               75,834 (0.15; 66,884;   ..............   2,006  Common year round.
                                                                                   2012).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\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.

[[Page 19716]]

 
\2\ Stock abundance as reported in NMFS marine mammal stock assessment reports except where otherwise noted. NMFSs abundance reports available online
  at: www.nmfs.noaa.gov/pr/sars. 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 2017 draft Atlantic SARs.
\3\ This information represents species- or guild-specific abundance predicted by recent habitat-based cetacean density models (Roberts et al., 2016).
  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).
\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) 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) 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\ Abundance as reported in the 2007 Canadian Trans-North Atlantic Sighting Survey (TNASS), which provided full coverage of the Atlantic Canadian coast
  (Lawson and Gosselin, 2009). Abundance estimates from TNASS were corrected for perception and availability bias, when possible. In general, where the
  TNASS survey effort provided superior coverage of a stock's range (as compared with NOAA shipboard survey effort), the resulting abundance estimate is
  considered more accurate than the current NMFS abundance estimate (derived from survey effort with inferior coverage of the stock range). NMFS stock
  abundance estimate for the common dolphin is 70,184. NMFS stock abundance estimate for the fin whale is 1,618.
\7\ 2017 U.S. Atlantic draft SAR for the Gulf of Maine feeding population lists a current abundance estimate of 335 individuals; this estimate was
  revised from the previous estimate of 823 individuals. However, the newer estimate is based on a single aerial line-transect survey in the Gulf of
  Maine. The 2017 U.S. Atlantic draft SAR notes that that previous estimate was based on a minimum number alive calculation which is generally more
  accurate than one derived from line-transect survey (Hayes et al., 2017), and that the abundance estimate was revised solely because the previous
  estimate was greater than 8 years old. Therefore, the previous estimate of 823 is more accurate, and we note that even that estimate is defined on the
  basis of feeding location alone (i.e., Gulf of Maine).
\8\ NMFS stock abundance estimate applies to U.S. population only, actual stock abundance is approximately 505,000.

    Four marine mammal species that are listed under the Endangered 
Species Act (ESA) may be present in the survey area and are included in 
the take request: The North Atlantic right whale, fin whale, sei whale, 
and sperm whale.
    Below is a description of the species that are both common in the 
survey area south of Rhode Island and Massachusetts that have the 
highest likelihood of occurring, at least seasonally, in the survey 
area and are thus are expected to potentially be taken by the proposed 
activities. Though other marine mammal species are known to occur in 
the Northwest Atlantic Ocean, the temporal and/or spatial occurrence of 
several of these species is such that take of these species is not 
expected to occur, and they are therefore not discussed further beyond 
the explanation provided here. Take of these species is not anticipated 
either because they have very low densities in the project area (e.g., 
blue whale, Clymene dolphin, pantropical spotted dolphin, striped 
dolphin, spinner dolphin, killer whale, false killer whale, pygmy 
killer whale, short-finned pilot whale), or, are known to occur further 
offshore than the project area (e.g., beaked whales, rough toothed 
dolphin, Kogia spp.). 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. For 
humpback and sei whales, NMFS defines stocks on the basis of feeding 
locations, i.e., Gulf of Maine and Nova Scotia, respectively. However, 
our reference to humpback whales and sei whales in this document refers 
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 the calving grounds in 
the southeastern United States to feeding grounds in New England waters 
and into Canadian waters (Waring et al., 2016). Surveys have 
demonstrated the existence of seven areas where North Atlantic right 
whales congregate seasonally, including north and east of the proposed 
survey area in Georges Bank, off Cape Cod, and in Massachusetts Bay 
(Waring et al., 2016). 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 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 Ocean demonstrated nearly continuous year-round right whale 
presence across their entire habitat range, 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). Acoustic monitoring data from 2004 to 2014 indicated that the 
number of North Atlantic right whale vocalizations detected in the 
proposed survey area were relatively constant throughout the year, with 
the exception of August through October when detected vocalizations 
showed an apparent decline (Davis et al. 2017). North Atlantic right 
whales are expected to be present in the proposed survey area during 
the proposed survey, especially during the summer months, with numbers 
possibly lower in the fall.
    The western North Atlantic 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). In 2018, no new North Atlantic right whale 
calves were documented in their calving grounds; this represented the 
first time since annual NOAA aerial surveys began in 1989 that no new 
right whale calves were observed.
    Data indicates that the number of adult females fell from 200 in 
2010 to 186 in 2015 while males fell from 283 to 272 in the same time 
frame (Pace et al., 2017). In addition, elevated North Atlantic right 
whale mortalities have occurred since June 7, 2017. A total of 18 
confirmed dead stranded whales (12 in Canada; 6 in the United States), 
with an additional 5 live whale entanglements in Canada, have been 
documented to date. This event has been declared an Unusual Mortality 
Event (UME), with human interactions (i.e., fishery-related 
entanglements and vessel strikes) identified as the most likely cause. 
More information is available online at: https://www.nmfs.noaa.gov/pr/health/mmume/2017northatlanticrightwhaleume.html.
    The proposed survey area is part of an important migratory area for 
North Atlantic right whales; this important

[[Page 19717]]

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. A 
portion of one SMA, which occurs off Block Island, Rhode Island, 
overlaps spatially with a section of the proposed survey area. The SMA 
which occurs off Block Island is active from November 1 through April 
30 of each year.

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 humpbacks 
continued to be listed as endangered. NMFS recently evaluated the 
status of the species, and 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 62259; 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 whale that is 
expected to occur in the survey area. The best estimate of population 
abundance for the West Indies DPS is 12,312 individuals, as described 
in the NMFS Status Review of the Humpback Whale under the Endangered 
Species Act (Bettridge et al., 2015).
    In New England waters, feeding is the principal activity of 
humpback whales, and their distribution in this region has been largely 
correlated to abundance of prey species, although behavior and 
bathymetry are factors influencing foraging strategy (Payne et al. 
1986, 1990). Humpback whales are frequently piscivorous when in New 
England waters, feeding on herring (Clupea harengus), sand lance 
(Ammodytes spp.), and other small fishes, as well as euphausiids in the 
northern Gulf of Maine (Paquet et al. 1997). During winter, the 
majority of humpback whales from North Atlantic feeding areas 
(including the Gulf of Maine) mate and calve in the West Indies, where 
spatial and genetic mixing among feeding groups occurs, though 
significant numbers of animals are found in mid- and high-latitude 
regions at this time and some individuals have been sighted repeatedly 
within the same winter season, indicating that not all humpback whales 
migrate south every winter (Waring et al., 2016).
    Since January 2016, elevated humpback whale mortalities have 
occurred along the Atlantic coast from Maine through North Carolina. 
Partial or full necropsy examinations have been conducted on 
approximately half of the 62 known cases. A portion of the whales have 
shown evidence of pre-mortem vessel strike; however, this finding is 
not consistent across all of the whales examined so 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.nmfs.noaa.gov/pr/health/mmume/2017humpbackatlanticume.html.

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, though densities vary seasonally (Waring 
et al., 2016). Fin whales are 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). 
The proposed survey area would overlap spatially and temporally with a 
biologically important feeding area for fin whales. The important fin 
whale feeding area occurs from March through October and stretches from 
an area south of Montauk Point to south of Martha's Vineyard.

Sei Whale

    The Nova Scotia stock of sei whales can be found in deeper waters 
of the continental shelf edge waters of the northeastern United States 
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 engendered under the ESA and the Nova Scotia stock is 
considered strategic and depleted under the MMPA.

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 which spring to fall 
are times of relatively widespread and common occurrence, and when the 
whales are most abundant in New England waters, while during winter the 
species appears to be largely absent (Waring et al., 2016).

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 are found from North Carolina and north to 
Iceland, Greenland and the Barents Sea (Waring et al., 2016). 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, pilot whales move onto Georges Bank 
and into the Gulf of Maine and more northern waters and remain in

[[Page 19718]]

these areas through late autumn (Waring et al., 2016). Long-finned 
pilot whales are not listed under the ESA. The Western North Atlantic 
stock is considered strategic under the MMPA.

Atlantic White-Sided Dolphin

    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). Atlantic 
spotted dolphins are not listed under the ESA and the stock is not 
considered depleted or strategic under the MMPA.

Common Dolphin

    The short-beaked common dolphin is found world-wide in temperate to 
subtropical seas. In the North Atlantic, short-beaked 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). Only the western North 
Atlantic stock may be present in the Lease Area.

Bottlenose Dolphin

    There are two distinct bottlenose dolphin ecotypes 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 and is the only type that may be 
present in the survey area as the survey area is north of the northern 
extent of the range of the Western North Atlantic Northern Migratory 
Coastal Stock.

Harbor Porpoise

    In the Lease Area, 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). Haulout 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).

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).

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 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-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 
kilohertz (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

[[Page 19719]]

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 (2016) 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 2). 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-Pascal) to identify the 
medium. For air and water, these reference pressures are ``re: 20 micro 
Pascals ([mu]Pa)'' and ``re: 1 [mu]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 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

[[Page 19720]]

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 Level B harassment that is mediated by 
physiological effects on the auditory system.
    Animals in the Lease Area during the HRG survey 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 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 1) 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

[[Page 19721]]

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 1)) 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 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-

[[Page 19722]]

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 are few data 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 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.

[[Page 19723]]

    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 
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 DWW'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

[[Page 19724]]

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. Richardson et al. (1995) went on to explain that 
seals on haul-outs sometimes respond strongly to the presence of 
vessels and at other times appear to show considerable tolerance of 
vessels, and Brueggeman et al. (1992) observed ringed seals (Pusa 
hispida) hauled out on ice pans displaying short-term escape reactions 
when a ship approached within 0.16-0.31 miles (0.25-0.5 km). Due to the 
relatively high vessel traffic in the Lease Area it is possible that 
marine mammals are habituated to noise (e.g., DP thrusters) from 
project vessels in the area.

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 knots (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, DWW 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 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

[[Page 19725]]

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, 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, as use of the HRG 
equipment has the potential to result in disruption of behavioral 
patterns for individual marine mammals. NMFS has determined take by 
Level A harassment is not an expected outcome of the proposed activity 
and thus we do not propose to authorize the take of any marine mammals 
by Level A harassment. This is discussed in greater detail below. As 
described previously, no mortality or serious injury is anticipated or 
proposed to be authorized for this activity. Below we describe how the 
take is estimated for this project.
    Described in the most basic way, 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. Below, we describe these 
components in more detail and present the proposed take estimate.

Acoustic Thresholds

    NMFS uses 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 
sound source (e.g., frequency, predictability, duty cycle); the 
environment (e.g., bathymetry); and the receiving animals (hearing, 
motivation, experience, demography, behavioral context); therefore can 
be difficult to predict (Southall et al., 2007, Ellison et al. 2012). 
NMFS uses a generalized acoustic threshold based on received level to 
estimate the onset of Level B (behavioral) harassment. NMFS predicts 
that marine mammals may be behaviorally harassed when exposed to 
underwater anthropogenic noise above received levels 160 dB re 1 [mu]Pa 
(RMS) for non-explosive impulsive (e.g., seismic HRG equipment) or 
intermittent (e.g., scientific sonar) sources. DWW's proposed activity 
includes the use of impulsive sources. Therefore, the 160 dB re 1 
[mu]Pa (RMS) criteria is applicable for analysis of Level B harassment.
    Level A Harassment--NMFS' Technical Guidance for Assessing the 
Effects of Anthropogenic Sound on Marine Mammal Hearing (NMFS 2016) 
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 Technical Guidance identifies the 
received levels, or thresholds, above which individual marine mammals 
are predicted to experience changes in their hearing sensitivity for 
all underwater anthropogenic sound sources, reflects the best available 
science, and better predicts the potential for auditory injury than 
does NMFS' historical criteria.
    These thresholds were developed by compiling and synthesizing the 
best available science and soliciting input multiple times from both 
the public and peer reviewers to inform the final product, and are 
provided in Table 3 below. The references, analysis, and methodology 
used in the development of the thresholds are described in NMFS 2016 
Technical Guidance, which may be accessed at: www.nmfs.noaa.gov/pr/acoustics/guidelines.htm. As described above, DWW's proposed activity 
includes the use of intermittent and impulsive sources.

 Table 3--Thresholds Identifying the Onset of Permanent Threshold Shift
                            in Marine Mammals
------------------------------------------------------------------------
                                          PTS onset thresholds
        Hearing group         ------------------------------------------
                                  Impulsive *         Non-impulsive
------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans.  Lpk,flat: 219     LE,LF,24h: 199 dB.
                                dB; LE,LF,24h:
                                183 dB.
Mid-Frequency (MF) Cetaceans.  Lpk,flat: 230     LE,MF,24h: 198 dB.
                                dB; LE,MF,24h:
                                185 dB.
High-Frequency (HF) Cetaceans  Lpk,flat: 202     LE,HF,24h: 173 dB.
                                dB; LE,HF,24h:
                                155 dB.
Phocid Pinnipeds (PW)          Lpk,flat: 218     LE,PW,24h: 201 dB.
 (Underwater).                  dB; LE,PW,24h:
                                185 dB.
------------------------------------------------------------------------
Note: *Dual metric acoustic thresholds for impulsive sounds: Use
  whichever results in the largest isopleth for calculating PTS onset.
  If a non-impulsive sound has the potential of exceeding the peak sound
  pressure level thresholds associated with impulsive sounds, these
  thresholds should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [mu]Pa, and
  cumulative sound exposure level (LE) has a reference value of
  1[mu]Pa2s. 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.


[[Page 19726]]

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into estimating the area ensonified above the 
acoustic thresholds.
    The proposed survey would entail the use of HRG survey equipment. 
The distance to the isopleth corresponding to the threshold for Level B 
harassment was calculated for all HRG survey equipment with the 
potential to result in harassment of marine mammals using the spherical 
transmission loss (TL) equation: TL = 20log10[gamma]. 
Results of modeling indicated that, of the HRG survey equipment planned 
for use that has the potential to result in harassment of marine 
mammals, the AA Dura-Spark would be expected to produce sound that 
would propagate the furthest in the water (Table 4); therefore, for the 
purposes of the take calculation, it was assumed the AA Dura-Spark 
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 AA Dura-Spark (estimated at 447 m; Table 4) was used as the basis 
of the Level B take calculation for all marine mammals.

Table 4--Modeled Radial Distances From HRG Survey Equipment to Isopleths
              Corresponding to Level B Harassment Threshold
------------------------------------------------------------------------
                                                              Radial
                                                           distance (m)
                                                            to Level B
                       HRG system                           harassment
                                                             threshold
                                                           (160 dB  re 1
                                                              [mu]Pa)
------------------------------------------------------------------------
TB Chirp................................................           70.79
EdgeTech Chirp..........................................            6.31
AA Boomer...............................................            5.62
AA S-Boom...............................................          141.25
Bubble Gun..............................................            63.1
800J Spark..............................................          141.25
AA Dura Spark...........................................          446.69
------------------------------------------------------------------------

    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, 
2016) 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., 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. In recognition of the fact that calculating Level A 
harassment ensonified areas could be more technically challenging to 
predict due to the duration component and the use of weighting 
functions in the new SELcum thresholds, NMFS developed an 
optional User Spreadsheet that includes tools to help predict a simple 
isopleth that can be used in conjunction with marine mammal density or 
occurrence to facilitate the estimation of take numbers. DWW used the 
NMFS optional User Spreadsheet to calculate distances to Level A 
harassment isopleths based on SELcum. To calculate distances 
to the Level A harassment isopleths based on peak pressure, the 
spherical spreading loss model was used (similar to the method used to 
calculate Level B isopleths as described above).
    Modeling of distances to isopleths corresponding to Level A 
harassment was performed for all types of HRG equipment planned for use 
with the potential to result in harassment of marine mammals. Of the 
HRG equipment types modeled, the AA Dura Spark resulted in the largest 
distances to isopleths corresponding to Level A harassment for all 
marine mammal functional hearing groups; therefore, to be conservative, 
the isopleths modeled for the AA Dura Spark were used to estimate 
potential Level A take. Based on a conservative assumption that the AA 
Dura Spark would be operated at 1,000 joules during the survey, a peak 
source level of 223 dB re 1[mu]Pa was used for modeling Level A 
harassment isopleths based on peak pressure (Crocker & Fratantonio, 
2016). Inputs to the NMFS optional User Spreadsheet for the AA Dura 
Spark are shown in Table 5. Modeled distances to isopleths 
corresponding to Level A harassment thresholds for the AA Dura Spark 
are shown in Table 6 (modeled distances to Level A harassment isopleths 
for all other types of HRG equipment planned for use are shown in Table 
6 of the IHA application). As described above, NMFS considers onset of 
PTS (Level A harassment) to have occurred when either one of the two 
metrics is exceeded (i.e., metric resulting in the largest isopleth).

  Table 5--Inputs to the NMFS Optional User Spreadsheet for the AA Dura
                                  Spark
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Source Level (RMS SPL) \1\................  213 dB re 1[mu]Pa.
Source Level (peak) \1\...................  223 dB re 1[mu]Pa.
Weighting Factor Adjustment (kHz) \1\.....  3.2.
Source Velocity (meters/second)...........  2.07.
Pulse Duration (seconds)..................  0.0021.
1/Repetition rate (seconds)...............  2.42.
Duty Cycle................................  0.00.
------------------------------------------------------------------------
\1\ Derived from Crocker & Fratantonio (2016), based on operation at
  1,000 joules.


 Table 6--Modeled Radial Distances to Isopleths Corresponding to Level A
                          Harassment Thresholds
------------------------------------------------------------------------
                                                              Radial
                                              Radial       distance (m)
                                           distance (m)     to Level A
    Functional hearing group (Level A       to Level A      harassment
         harassment thresholds)             harassment       threshold
                                             threshold    (Peak SPLflat)
                                             (SELcum)
------------------------------------------------------------------------
Low frequency cetaceans.................             1.3             1.6
(Lpk,flat: 219 dB; LE,LF,24h: 183 dB)...
Mid frequency cetaceans.................             0.0             0.0
(Lpk,flat: 230 dB; LE,MF,24h: 185 dB)...
High frequency cetaceans................             8.6            11.2
(Lpk,flat: 202 dB; LE,HF,24h: 155 dB)...
Phocid Pinnipeds (Underwater)...........             0.7             1.8
(Lpk,flat: 218 dB; LE,HF,24h: 185 dB)...
------------------------------------------------------------------------


[[Page 19727]]

    Due to the small estimated distances to Level A harassment 
thresholds for all marine mammal functional hearing groups, based on 
both SELcum and peak SPL (Table 6), and in consideration of 
the proposed mitigation measures (see the Proposed Mitigation section 
for more detail), NMFS has determined that the likelihood of Level A 
take of marine mammals occurring as a result of the proposed survey is 
so low as to be discountable.
    We note that because of some of the assumptions included in the 
methods used, isopleths produced may be overestimates to some degree. 
Most of the acoustic sources proposed for use in DWW's survey 
(including the AA Dura-Spark) do not radiate sound equally in all 
directions but were designed instead to focus acoustic energy directly 
toward the sea floor. Therefore, the acoustic energy produced by these 
sources is not received equally in all directions around the source but 
is instead concentrated along some narrower plane depending on the 
beamwidth of the source. However, the calculated distances to isopleths 
do not account for this directionality of the sound source and are 
therefore conservative. Two types of geophysical survey equipment 
planned for use in the proposed survey are omni-directional (Table 1), 
however the modeled distances to isopleths corresponding to the Level B 
harassment threshold for these sources are smaller than that for the 
Dura Spark (Table 1), and the Dura Spark was used to conservatively 
estimate take for the duration of the survey. For mobile sources, such 
as the proposed survey, the User Spreadsheet predicts the closest 
distance at which a stationary animal would not incur PTS if the sound 
source traveled by the animal in a straight line at a constant speed.

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 best available scientific information was considered in 
calculating marine mammal exposure estimates (the basis for estimating 
take). For cetacean species, densities calculated by Roberts et al. 
(2016) were used. The density data presented by Roberts et al. (2016) 
incorporates aerial and shipboard line-transect survey data from NMFS 
and from other organizations collected over the period 1992-2014. 
Roberts et al. (2016) modeled density from 8 physiographic and 16 
dynamic oceanographic and biological covariates, and controlled for the 
influence of sea state, group size, availability bias, and perception 
bias on the probability of making a sighting. NMFS considers the models 
produced by Roberts et al. (2016) to be the best available source of 
data regarding cetacean densities for this project. More information, 
including the model results and supplementary information for each 
model, is available online at: seamap.env.duke.edu/models/Duke-EC-GOM-2015/.
    For the purposes of the take calculations, density data from 
Roberts et al. (2016) were mapped using a geographic information system 
(GIS), using density data for the months June through December. Mean 
density per month for each species within the survey area was 
calculated by selecting 13 random raster cells selected from 100 km\2\ 
raster cells that were inside, or adjacent to, the RI-MA WEA (see 
Figure 1 in the IHA application). Estimates provided by the models are 
based on a grid cell size of 100 km\2\; therefore, model grid cell 
values were then divided by 100 to determine animals per square km.
    Systematic, offshore, at-sea survey data for pinnipeds are more 
limited than those for cetaceans. The best available information 
concerning pinniped densities in the proposed survey area is the U.S. 
Navy's Operating Area (OPAREA) Density Estimates (NODEs) (DoN, 2007). 
These density models utilized vessel-based and aerial survey data 
collected by NMFS from 1998-2005 during broad-scale abundance studies. 
Modeling methodology is detailed in DoN (2007). For the purposes of the 
take calculations, NODEs Density Estimates (DoN, 2007) as reported for 
the summer and fall seasons were used to estimate harbor seal and gray 
seal densities.

Take Calculation and Estimation

    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 of 
the survey 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. DWW estimates a maximum 
daily track line distance of 110 km per day during HRG surveys. Based 
on the maximum estimated distance to the Level B harassment threshold 
of 447 m (Table 4) and the maximum estimated daily track line distance 
of 110 km, an area of 98.9 km\2\ would be ensonified to the Level B 
harassment threshold per day during HRG surveys.
    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, using estimated 
marine mammal densities as described above. Estimated numbers of each 
species taken per day are then multiplied by the number of survey days 
(i.e., 200), and the product is then rounded, to generate an estimate 
of the total number of each species expected to be taken over the 
duration of the survey (Table 7).
    The applicant estimated a total of 11 takes by Level A harassment 
of harbor porpoises, 5 takes by Level A harassment of harbor seals, and 
7 takes by Level A harassment of gray seals would occur, in the absence 
of mitigation. However, as described above, due to the very small 
estimated distances to Level A harassment thresholds (Table 6), and in 
consideration of the proposed mitigation measures, the likelihood of 
the proposed survey resulting in take in the form of Level A harassment 
is considered so low as to be discountable; therefore, we do not 
propose to authorize take of any marine mammals by Level A harassment. 
Although there are no exclusion zones (EZs) proposed for pinnipeds, the 
estimated distance to the isopleth corresponding to the Level A 
harassment threshold for pinnipeds is less than 2 m (Table 6); 
therefore, we determined the likelihood of an animal being taken within 
this proximity of the survey equipment to be so low as to be 
discountable. Proposed take numbers are shown in Table 7.

[[Page 19728]]



    Table 7--Total Numbers of Potential Incidental Take of Marine Mammals Proposed for Authorization and Proposed Takes as a Percentage of Population
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                         Total proposed
                                                        Density (#/100  Proposed Level     Estimated    Proposed Level  Total Proposed     takes as a
                        Species                             km\2\)          A takes      Level B takes      B takes          takes        percentage of
                                                                                                                                         population \1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
North Atlantic right whale............................         0.01706               0               3               3               3               0.6
Humpback whale........................................         0.14439               0              29              29              29               1.8
Fin whale \2\.........................................         0.21353               0              42              42              42               1.2
Sei whale \3\.........................................           0.005               0               1               2               2               0.3
Minke whale...........................................         0.04745               0               9               9               9              <0.1
Sperm whale...........................................         0.00665               0               1               1               1              <0.1
Long-finned pilot whale \3\...........................         0.15364               0              30              32              32               0.2
Bottlenose dolphin....................................         1.60936               0             318             318             318               0.3
Atlantic Spotted dolphin \3\..........................         0.00886               0               2              50              50               0.1
Common dolphin \2\....................................         4.59986               0             910             910             910               0.5
Atlantic white-sided dolphin..........................          1.8036               0             357             357             357               1.0
Harbor porpoise \4\...................................         2.53125               0             501             501             501               1.1
Harbor seal...........................................         6.49533               0           1,285           1,285           1,285               1.7
Gray seal.............................................         9.41067               0           1,861           1,861           1,861               6.9
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Estimates of total proposed takes as a percentage of population are based on marine mammal abundance estimates provided by Roberts et al. (2016),
  when available, except where noted otherwise, to maintain consistency with density estimates which are derived from data provided by Roberts et al.
  (2016). In cases where abundances are not provided by Roberts et al. (2016), total proposed takes as a percentage of population are based on abundance
  estimates in the NMFS Atlantic SARs (Hayes et al., 2018).
\2\ Estimates of total proposed takes as a percentage of population are based on marine mammal abundance estimates as reported in the 2007 TNASS (Lawson
  and Gosselin, 2009) (Table 2). Abundance estimates from TNASS were corrected for perception and availability bias, when possible. In general, where
  the TNASS survey effort provided superior coverage of a stock's range (as compared with NOAA shipboard survey effort), the resulting abundance
  estimate is considered more accurate than abundance estimates based on NMFS surveys.
\3\ The proposed number of authorized takes (Level B harassment only) for these species has been increased from the estimated take to mean group size.
  Source for sei whale group size estimate is: Schilling et al. (1992). Source for long-finned pilot whale group size estimate is: Augusto et al.
  (2017). Source for Atlantic spotted dolphin group size estimate is: Jefferson et al. (2008).
\4\ The density estimate in the IHA application is incorrectly shown as 0.0225781 animals/km2. The correct density estimate is reflected in Table 7.

    Species with Take Estimates Less than Mean Group Size: Using the 
approach described above to estimate take, the take estimates for the 
sei whale, long-finned pilot whale and Atlantic spotted dolphin were 
less than the average group sizes estimated for these species (Table 
6). However, information on the social structures and life histories of 
these species indicates these species are often encountered in groups. 
The results of take calculations support the likelihood that the 
proposed survey is expected to encounter and to incidentally take these 
species, and we believe it is likely that these species may be 
encountered in groups. Therefore it is reasonable to conservatively 
assume that one group of each of these species will be taken during the 
proposed survey. We propose to authorize the take of the average group 
size for these species and stocks to account for the possibility that 
the proposed survey encounters a group of any of these species or 
stocks (Table 7). Note that the take estimate for the sperm whale was 
not increased to average group size because, based on water depths in 
the proposed survey area (16 to 28 m (52 to 92 ft)), it is very 
unlikely that groups of sperm whales, which tend to prefer deeper 
depths, would be encountered by the proposed survey.

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)).
    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 relative cost and 
impact on operations.

Proposed Mitigation Measures

    With NMFS' input during the application process, and as per the 
BOEM Lease, DWW is proposing the following mitigation measures during 
the proposed marine site characterization surveys.

Marine Mammal Exclusion and Watch Zones

    Marine mammal exclusion zones (EZ) will be established around the 
HRG survey equipment and monitored by protected species observers (PSO) 
during HRG surveys as follows:
     500 m EZ for North Atlantic right whales;
     200 m EZ for all other ESA-listed cetaceans (including fin 
whale, sei whale and sperm whale); and

[[Page 19729]]

     25 m EZ for harbor porpoises.
    The applicant proposed a 500 m EZ for North Atlantic right whales 
and 200 m EZ for all other marine mammal species; however, for non-ESA-
listed marine mammals, based on estimated distances to isopleths 
corresponding with Level A harassment thresholds (Table 5), we 
determined EZs for species other than those described above were not 
warranted. In addition to the EZs described above, PSOs will visually 
monitor and record the presence of all marine mammals within 500 m.

Visual Monitoring

    As per the BOEM lease, visual and acoustic monitoring of the 
established exclusion and monitoring zones will be performed by four 
qualified and NMFS-approved PSOs. It would be the responsibility of the 
Lead PSO on duty to communicate the presence of marine mammals as well 
as to communicate and enforce the action(s) that are necessary to 
ensure mitigation and monitoring requirements are implemented as 
appropriate. PSOs would be equipped with binoculars and would estimate 
distances to marine mammals located in proximity to the vessel and/or 
exclusion zone using range finders. Reticulated binoculars would also 
be available to PSOs for use as appropriate based on conditions and 
visibility to support the siting and monitoring of marine species. 
Position data will be recorded using hand-held or vessel global 
positioning system (GPS) units for each sighting. Observations will 
take place from the highest available vantage point on the survey 
vessel. During surveys conducted at night, night-vision equipment with 
infrared light-emitting diodes spotlights and/or infrared video 
monitoring will be available for PSO use, and passive acoustic 
monitoring (PAM; described below) will be used (as required per the 
BOEM lease).

Pre-Clearance of the Exclusion Zone

    Prior to initiating HRG survey activities, DWW would implement a 
30-minute pre-clearance period. During this period, the 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). Survey 
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. This 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.

Passive Acoustic Monitoring

    As proposed by the applicant and required by the BOEM lease, PAM 
will be used to support monitoring during night time operations to 
provide for optimal acquisition of species detections at night. The PAM 
system will consist of an array of hydrophones with both broadband 
(sampling mid-range frequencies of 2 kHz to 200 kHz) and at least one 
low-frequency hydrophone (sampling range frequencies of 75 Hz to 30 
kHz). The PAM operator(s) will monitor acoustic signals in real time 
both aurally (using headphones) and visually (via sound analysis 
software). PAM operators will communicate nighttime detections to the 
lead PSO on duty who will ensure the implementation of the appropriate 
mitigation measure. However, PAM detection alone would not trigger a 
requirement that any mitigation action be taken upon acoustic detection 
of marine mammals.

Ramp-Up of Survey Equipment

    As proposed by the applicant, where 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 use at full energy. Ramp-up of the survey equipment would not 
begin until the relevant EZ has been cleared by the PSOs, as described 
above. Systems will be initiated at their lowest power output and will 
be incrementally increased to full power. If any marine mammals are 
detected within the EZ prior to or during the ramp-up, HRG equipment 
will be shut down (as described below).

Shutdown Procedures

    As required in the BOEM lease, if a marine mammal is observed 
within or approaching the relevant EZ (as described above) an immediate 
shutdown of the survey equipment is required. Subsequent restart of the 
survey equipment may only occur after the animal(s) has either been 
observed exiting the relevant EZ or until an additional time period has 
elapsed with no further sighting of the animal (e.g., 15 minutes for 
harbor porpoise and 30 minutes for North Atlantic right whale, fin 
whale, sei whale and sperm whale).
    As required in the BOEM lease, if the HRG equipment shuts down for 
reasons other than mitigation (i.e., mechanical or electronic failure) 
resulting in the cessation of the survey equipment for a period greater 
than 20 minutes, a 30 minute pre-clearance period (as described above) 
would precede the restart of the HRG survey equipment. If the pause is 
less than less than 20 minutes, the equipment may be restarted as soon 
as practicable at its full operational level only if visual surveys 
were continued diligently throughout the silent period and the EZs 
remained clear of marine mammals during that entire period. If visual 
surveys were not continued diligently during the pause of 20 minutes or 
less, a 30-minute pre-clearance period (as described above) would 
precede the re-start of the HRG survey equipment. Following a shutdown, 
HRG survey equipment may be restarted following pre-clearance of the 
zones as described above.
    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 (450 m), shutdown 
would occur.

Vessel Strike Avoidance

    Vessel strike avoidance measures will include, but are not limited 
to, the following, as required in the BOEM lease, except under 
circumstances when complying with these requirements would put the 
safety of the vessel or crew at risk:
     All vessel operators and crew will maintain vigilant watch 
for cetaceans and pinnipeds, and slow down or stop their vessel to 
avoid striking these protected species;
     All vessel operators will comply with 10 knot (18.5 km/hr) 
or less speed restrictions in any SMA and DMA per NOAA guidance;
     All vessel operators will reduce vessel speed to 10 knots 
(18.5 km/hr) or less when any large whale, any mother/calf pairs, large 
assemblages of non-delphinoid cetaceans are observed near (within 100 m 
(330 ft)) an underway vessel;
     All survey vessels will maintain a separation distance of 
500 m (1640 ft) or greater from any sighted North Atlantic right whale;
     If underway, vessels must steer a course away from any 
sighted North Atlantic right whale at 10 knots (18.5 km/hr) or less 
until the 500 m (1640 ft) minimum separation distance has been

[[Page 19730]]

established. If a North Atlantic right whale is sighted in a vessel's 
path, or within 100 m (330 ft) to an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. Engines will 
not be engaged until the North Atlantic right whale has moved outside 
of the vessel's path and beyond 100 m. If stationary, the vessel must 
not engage engines until the North Atlantic right whale has moved 
beyond 100 m;
     All vessels will maintain a separation distance of 100 m 
(330 ft) or greater from any sighted non-delphinoid cetacean. If 
sighted, the vessel underway must reduce speed and shift the engine to 
neutral, and must not engage the engines until the non-delphinoid 
cetacean has moved outside of the vessel's path and beyond 100 m. If a 
survey vessel is stationary, the vessel will not engage engines until 
the non-delphinoid cetacean has moved out of the vessel's path and 
beyond 100 m;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted delphinoid cetacean. Any vessel 
underway remain parallel to a sighted delphinoid cetacean's course 
whenever possible, and avoid excessive speed or abrupt changes in 
direction. Any vessel underway reduces vessel speed to 10 knots (18.5 
km/hr) or less when pods (including mother/calf pairs) or large 
assemblages of delphinoid cetaceans are observed. Vessels may not 
adjust course and speed until the delphinoid cetaceans have moved 
beyond 50 m and/or the abeam of the underway vessel;
     All vessels will maintain a separation distance of 50 m 
(164 ft) or greater from any sighted pinniped; and
     All vessels underway will not divert or alter course in 
order to approach any whale, delphinoid cetacean, or pinniped. Any 
vessel underway will avoid excessive speed or abrupt changes in 
direction to avoid injury to the sighted cetacean or pinniped.
    DWW will ensure that vessel operators and crew maintain a vigilant 
watch for cetaceans and pinnipeds by slowing down or stopping the 
vessel to avoid striking marine mammals. Project-specific training will 
be conducted for all vessel crew prior to the start of the site 
characterization survey activities. Confirmation of the training and 
understanding of the requirements will be documented on a training 
course log sheet. Signing the log sheet will certify that the crew 
members understand and will comply with the necessary requirements 
throughout the survey activities.

Seasonal Operating Requirements

    As described above, the northern section of the proposed survey 
area partially overlaps with a portion of a North Atlantic right whale 
SMA which occurs east of Long Island, New York, and south of 
Massachusetts and Rhode Island. This SMA is active from November 1 
through April 30 of each year. Survey vessels that are >65 ft in length 
would be required to adhere to the mandatory vessel speed restrictions 
(<10 kn) when operating within the SMA during times when the SMA is 
active. In addition, between watch shifts, members of the monitoring 
team would consult NMFS' North Atlantic right whale reporting systems 
for the presence of North Atlantic right whales throughout survey 
operations. Members of the monitoring team would monitor the NMFS North 
Atlantic right whale reporting systems for the establishment of a 
Dynamic Management Area (DMA). If NMFS should establish a DMA in the 
survey area, within 24 hours of the establishment of the DMA DWW would 
coordinate with NMFS to shut down and/or alter the survey activities as 
needed to avoid right whales to the extent possible.
    The proposed mitigation measures are designed to avoid the already 
low potential for injury in addition to some Level B harassment, and to 
minimize the potential for vessel strikes. There are no known marine 
mammal rookeries or mating grounds in the survey area that would 
otherwise potentially warrant increased mitigation measures for marine 
mammals or their habitat (or both). The proposed survey would occur in 
an area that has been identified as a biologically important area for 
migration for North Atlantic right whales. However, given the small 
spatial extent of the survey area relative to the substantially larger 
spatial extent of the right whale migratory area, the survey is not 
expected to appreciably reduce migratory habitat nor to negatively 
impact the migration of North Atlantic right whales, thus mitigation to 
address the proposed survey's occurrence in North Atlantic right whale 
migratory habitat is not warranted. The proposed survey area would 
partially overlap spatially with a biologically important feeding area 
for fin whales. However, the fin whale feeding area is sufficiently 
large (2,933 km\2\), and the acoustic footprint of the proposed survey 
is sufficiently small (<100 km\2\ estimated to be ensonified to the 
Level B harassment threshold per day), that the survey is not expected 
to appreciably reduce fin whale feeding habitat nor to negatively 
impact the feeding of fin whales, thus mitigation to address the 
proposed survey's occurrence in fin whale feeding habitat is not 
warranted. Further, we believe the proposed mitigation measures are 
practicable for the applicant to implement.
    Based on our evaluation of the applicant's proposed measures, NMFS 
has preliminarily determined that the proposed mitigation measures 
provide the means of 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

[[Page 19731]]

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); and
     Mitigation and monitoring effectiveness.

Proposed Monitoring Measures

    As described above, visual monitoring of the EZs and monitoring 
zone will be performed by qualified and NMFS-approved PSOs. Observer 
qualifications would include completion of a PSO training course and 
documented field experience on a marine mammal observation vessel and/
or aerial surveys. As proposed by the applicant and required by BOEM, 
an observer team comprising a minimum of four NMFS-approved PSOs and a 
minimum of two certified PAM operator(s), operating in shifts, will be 
employed by DWW during the proposed surveys. PSOs and PAM operators 
will work in shifts such that no one monitor will work more than 4 
consecutive hours without a 2 hour break or longer than 12 hours during 
any 24-hour period. During daylight hours the PSOs will rotate in 
shifts of one on and three off, while during nighttime operations PSOs 
will work in pairs. The PAM operators will also be on call as necessary 
during daytime operations should visual observations become impaired. 
Each PSO will monitor 360 degrees of the field of vision. DWW will 
provide r[eacute]sum[eacute]s of all proposed PSOs and PAM operators 
(including alternates) to NMFS for review and approval at least 45 days 
prior to the start of survey operations.
    Also as described above, PSOs will be equipped with binoculars and 
have the ability to estimate distances to marine mammals located in 
proximity to the vessel and/or exclusion zone using range finders. 
Reticulated binoculars will also be available to PSOs for use as 
appropriate based on conditions and visibility to support the sighting 
and monitoring of marine species. During night operations, PAM and 
night-vision equipment with infrared light-emitting diode spotlights 
and/or infrared video monitoring will be used to increase the ability 
to detect marine mammals. Position data will be recorded using hand-
held or vessel global positioning system (GPS) units for each sighting. 
Observations will take place from the highest available vantage point 
on the survey vessel. General 360-degree scanning will occur during the 
monitoring periods, and target scanning by the PSO will occur when 
alerted of a marine mammal presence.
    Data on all PAM/PSO observations will be recorded based on standard 
PSO collection requirements. This will include dates, times, and 
locations of survey operations; time of observation, location and 
weather; details of marine mammal sightings (e.g., species, numbers, 
behavior); and details of any observed taking (e.g., behavioral 
disturbances or injury/mortality).

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), 
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, DWW will provide the 
reports described below as necessary during survey activities. In the 
unanticipated event that DWW's survey activities lead to an injury 
(Level A harassment) or mortality (e.g., ship-strike, gear interaction, 
and/or entanglement) of a marine mammal, DWW would immediately cease 
the specified activities and report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources and 
the NMFS Greater Atlantic Stranding Coordinator. The report would 
include the following information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Name and type of vessel involved;
     Vessel's speed during and leading up to the incident;
     Description of the incident;
     Status of all sound source use in the 24 hours preceding 
the incident;
     Water depth;
     Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the event. NMFS would work with DWW to minimize 
reoccurrence of such an event in the future. DWW would not resume 
activities until notified by NMFS.
    In the event that DWW discovers an injured or dead marine mammal 
and determines that the cause of the injury or death is unknown and the 
death is relatively recent (i.e., in less than a moderate state of 
decomposition), DWW would immediately report the incident to the Chief 
of the Permits and Conservation Division, Office of Protected Resources 
and the NMFS Greater Atlantic Stranding Coordinator. The report would 
include the same information identified in the paragraph above. 
Activities would be able to continue while NMFS reviews the 
circumstances of the incident. NMFS would work with DWW to determine if 
modifications in the activities are appropriate.
    In the event that DWW discovers an injured or dead marine mammal 
and determines that the injury or death is not associated with or 
related to the activities authorized in the IHA (e.g., previously 
wounded animal, carcass with moderate to advanced decomposition, or 
scavenger damage), DWW would report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, and 
the NMFS Greater Atlantic Regional Stranding Coordinator, within 24 
hours of the discovery. DWW would provide photographs or video footage 
(if available) or other documentation of the stranded animal sighting 
to NMFS. DWW may continue its operations under such a case.

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. 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.,

[[Page 19732]]

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.
    NMFS does not anticipate that serious injury or mortality would 
occur as a result of DWW'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 
section, non-auditory physical effects and vessel strike are not 
expected to occur.
    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 or decreased foraging (if such activity were occurring), 
reactions that are considered to be of low severity and with no lasting 
biological consequences (e.g., Southall et al., 2007).
    Potential impacts to marine mammal habitat were discussed 
previously in this document (see Potential Effects of the Specified 
Activity on Marine Mammals and their Habitat). Marine mammal habitat 
may be impacted by elevated sound levels, but these impacts would be 
temporary. 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 or mating grounds known to be biologically 
important to marine mammals within the proposed survey area. As 
described above, the proposed survey area would overlap spatially and 
temporally with a biologically important feeding area for fin whales. 
The important fin whale feeding area occurs from March through October 
and stretches from an area south of Montauk Point to south of Martha's 
Vineyard. However, the fin whale feeding area is sufficiently large 
(2,933 km\2\), and the acoustic footprint of the proposed survey is 
sufficiently small (<100 km\2\ estimated to be ensonified to the Level 
B harassment threshold per day), that fin whale feeding habitat would 
not be reduced appreciably. Any fin whales temporarily displaced from 
the proposed survey area would be expected to have sufficient remaining 
feeding habitat available to them, and would not be prevented from 
feeding in other areas within the biologically important feeding 
habitat. In addition, any displacement of fin whales from the survey 
area would be expected to be temporary in nature. Therefore, we do not 
expect fin whale feeding to be negatively impacted by the proposed 
survey. There are no feeding areas known to be biologically important 
to marine mammals within the proposed project area with the exception 
of the aforementioned feeding area for fin whales. There is no 
designated critical habitat for any ESA-listed marine mammals in the 
proposed survey area.
    The proposed survey area is within 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 south coast of Massachusetts and 
Rhode Island, 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 short in overall duration, and the 
fact that the spatial acoustic footprint of the proposed survey is very 
small relative to the spatial extent of the available migratory habitat 
in the area, right whale migration is not expected to be impacted by 
the proposed survey.
    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. 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 DWW'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 be temporary behavioral changes due to avoidance of the 
area around the survey vessel;
     The availability of alternate areas of similar habitat 
value for marine mammals to temporarily vacate the survey area during 
the proposed survey to avoid exposure to sounds from the activity;
     The proposed project area does not contain areas of 
significance for mating or calving;
     Effects on species that serve as prey species for marine 
mammals from the proposed survey would be temporary and would not be 
expected to reduce the availability of prey or to affect marine mammal 
feeding;
     The proposed mitigation measures, including visual and 
acoustic 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.

[[Page 19733]]

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Section 101(a)(5)(D) of the MMPA for specified 
activities other than military readiness activities. The MMPA does not 
define small numbers and so, in practice, where estimated numbers are 
available, NMFS compares the number of individuals taken to the most 
appropriate estimation of abundance of the relevant species or stock in 
our determination of whether an authorization is limited to small 
numbers of marine mammals. Additionally, other qualitative factors may 
be considered in the analysis, such as the temporal or spatial scale of 
the activities.
    The numbers of marine mammals that we propose for authorization to 
be taken, for all species and stocks, would be considered small 
relative to the relevant stocks or populations (less than 7 percent of 
each species and stocks). See Table 7. 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 the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks 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 Office of Protected Resources 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. 
BOEM consulted with NMFS GARFO under section 7 of the ESA on commercial 
wind lease issuance and site assessment activities on the Atlantic 
Outer Continental Shelf in Massachusetts, Rhode Island, New York and 
New Jersey Wind Energy Areas. NMFS GARFO issued a Biological Opinion 
concluding that these activities may adversely affect but are not 
likely to jeopardize the continued existence of the North Atlantic 
right, fin, and sperm whale. The Biological Opinion can be found online 
at: www.fisheries.noaa.gov/national/marine-mammal-protection/incidental-take-authorizations-other-energy-activities-renewable. NMFS 
will conclude the ESA section 7 consultation prior to reaching a 
determination regarding the proposed issuance of the authorization. If 
the IHA is issued, the Biological Opinion may be amended to include an 
incidental take statement for these marine mammal species, as 
appropriate.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to DWW for conducting marine site assessment surveys 
offshore Massachusetts and Rhode Island and along potential submarine 
cable routes from the date of issuance for a period of one year, 
provided the previously mentioned mitigation, monitoring, and reporting 
requirements are incorporated. This section contains a draft of the IHA 
itself. The wording contained in this section is proposed for inclusion 
in the IHA (if issued).
    1. This IHA is valid for a period of one year from the date of 
issuance.
    2. This IHA is valid only for marine site characterization survey 
activity, as specified in the IHA application, in the Atlantic Ocean.
    3. General Conditions
    (a) A copy of this IHA must be in the possession of DWW, the vessel 
operator and other relevant personnel, the lead PSO, and any other 
relevant designees of DWW operating under the authority of this IHA.
    (b) The species authorized for taking are listed in Table 6. The 
taking, by Level B harassment only, is limited to the species and 
numbers listed in Table 6. Any taking of species not listed in Table 6, 
or exceeding the authorized amounts listed in Table 6, is prohibited 
and may result in the modification, suspension, or revocation of this 
IHA.
    (c) The taking by injury, serious injury or death of any species of 
marine mammal is prohibited and may result in the modification, 
suspension, or revocation of this IHA.
    (d) DWW shall ensure that the vessel operator and other relevant 
vessel personnel are briefed on all responsibilities, communication 
procedures, marine mammal monitoring protocols, operational procedures, 
and IHA requirements prior to the start of survey activity, and when 
relevant new personnel join the survey operations.
    4. Mitigation Requirements--the holder of this Authorization is 
required to implement the following mitigation measures:
    (a) DWW shall use at least four (4) NMFS-approved protected species 
observers (PSOs) during HRG surveys. The PSOs must have no tasks other 
than to conduct observational effort, record observational data, and 
communicate with and instruct relevant vessel crew with regard to the 
presence of marine mammals and mitigation requirements. PSO resumes 
shall be provided to NMFS for approval prior to commencement of the 
survey.
    (b) Visual monitoring must begin no less than 30 minutes prior to 
initiation of survey equipment and must continue until 30 minutes after 
use of survey equipment ceases.
    (c) Exclusion Zones--PSOs shall establish and monitor marine mammal 
Exclusion Zones and Watch Zone. Exclusion Zones are as follows:
    (i) 500 m Exclusion Zone for North Atlantic right whales;
    (ii) 200 m Exclusion Zone for fin whales, sei whales, and sperm 
whales; and
    (iii) 25 m Exclusion Zone for harbor porpoises.
    (d) Watch Zone--PSOs shall monitor a marine mammal Watch Zone that 
shall encompass an area 500 m from the survey equipment. PSOs shall 
document and record the behavior of all marine mammals observed within 
the Watch Zone.
    (e) Shutdown requirements--If a marine mammal is observed within, 
entering, or approaching the relevant Exclusion Zones as described 
under 4(c) while geophysical survey equipment is operational, the 
geophysical survey equipment must be immediately shut down.
    (i) Any PSO on duty has the authority to call for shutdown of 
survey equipment. When there is certainty regarding the need for 
mitigation action, the relevant PSO(s) must call for such action 
immediately.
    (ii) When a shutdown is called for by a PSO, the shutdown must 
occur and any dispute resolved only following shutdown.

[[Page 19734]]

    (iii) Upon implementation of a shutdown, survey equipment may be 
reactivated when all marine mammals have been confirmed by visual 
observation to have exited the relevant Exclusion Zone or an additional 
time period has elapsed with no further sighting of the animal that 
triggered the shutdown (15 minutes for harbor porpoise and 30 minutes 
for North Atlantic right whales, fin whales, sei whales, and sperm 
whales).
    (iv) If geophysical equipment shuts down for reasons other than 
mitigation (i.e., mechanical or electronic failure) resulting in the 
cessation of the survey equipment for a period of less than 20 minutes, 
the equipment may be restarted as soon as practicable if visual surveys 
were continued diligently throughout the silent period and the relevant 
Exclusion Zones are confirmed by PSOs to have remained clear of marine 
mammals during the entire 20-minute period. If visual surveys were not 
continued diligently during the pause of 20 minutes or less, a 30-
minute pre-clearance period shall precede the restart of the 
geophysical survey equipment as described in 4(f). If the period of 
shutdown for reasons other than mitigation is greater than 20 minutes, 
a pre-clearance period shall precede the restart of the geophysical 
survey equipment as described in 4(f).
    (v) 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 450 m 
of the survey equipment, shutdown must occur.
    (f) Pre-clearance observation--30 minutes of pre-clearance 
observation shall be conducted prior to initiation of geophysical 
survey equipment. Geophysical survey equipment shall not be initiated 
if marine mammals are observed within 200 m of the survey equipment 
(500 m for North Atlantic right whales) during the pre-clearance 
period. If a marine mammal is observed within 200 m of geophysical 
survey equipment (500 m for North Atlantic right whales) during the 
pre-clearance period, initiation of the survey equipment will be 
delayed until the marine mammal(s) departs the 200 m zone (500 m for 
North Atlantic right whales).
    (g) Ramp-up--when technically feasible, survey equipment shall be 
ramped up at the start or re-start of survey activities. Ramp-up will 
begin with the power of the smallest acoustic equipment at its lowest 
practical power output appropriate for the survey. When technically 
feasible the power will then be gradually turned up and other acoustic 
sources added in way such that the source level would increase 
gradually.
    (h) Vessel Strike Avoidance--Vessel operator and crew must maintain 
a vigilant watch for all marine mammals and slow down or stop the 
vessel or alter course, as appropriate, to avoid striking any marine 
mammal, unless such action represents a human safety concern. Survey 
vessel crew members responsible for navigation duties shall receive 
site-specific training on marine mammal sighting/reporting and vessel 
strike avoidance measures. Vessel strike avoidance measures shall 
include the following, except under circumstances when complying with 
these requirements would put the safety of the vessel or crew at risk:
    (i) The vessel operator and crew shall maintain vigilant watch for 
cetaceans and pinnipeds, and slow down or stop the vessel to avoid 
striking marine mammals;
    (ii) The vessel operator shall reduce vessel speed to 10 knots 
(18.5 km/hr) or less when any large whale, any mother/calf pairs, whale 
or dolphin pods, or larger assemblages of non-delphinoid cetaceans are 
observed near (within 100 m (330 ft)) an underway vessel;
    (iii) The survey vessel shall maintain a separation distance of 500 
m (1,640 ft) or greater from any sighted North Atlantic right whale;
    (iv) If underway, the vessel must steer a course away from any 
sighted North Atlantic right whale at 10 knots (18.5 km/hr) or less 
until the 500 m (1,640 ft) minimum separation distance has been 
established. If a North Atlantic right whale is sighted in a vessel's 
path, or within 100 m (330 ft) to an underway vessel, the underway 
vessel must reduce speed and shift the engine to neutral. Engines will 
not be engaged until the North Atlantic right whale has moved outside 
of the vessel's path and beyond 100 m. If stationary, the vessel must 
not engage engines until the North Atlantic right whale has moved 
beyond 100 m;
    (v) The vessel shall maintain a separation distance of 100 m (330 
ft) or greater from any sighted non-delphinoid cetacean. If sighted, 
the vessel underway must reduce speed and shift the engine to neutral 
and must not engage the engines until the non-delphinoid cetacean has 
moved outside of the vessel's path and beyond 100 m. If a survey vessel 
is stationary, the vessel will not engage engines until the non-
delphinoid cetacean has moved out of the vessel's path and beyond 100 
m;
    (vi) The vessel shall maintain a separation distance of 50 m (164 
ft) or greater from any sighted delphinoid cetacean. Any vessel 
underway remain parallel to a sighted delphinoid cetacean's course 
whenever possible and avoid excessive speed or abrupt changes in 
direction. Any vessel underway reduces vessel speed to 10 knots (18.5 
km/hr) or less when pods (including mother/calf pairs) or large 
assemblages of delphinoid cetaceans are observed. Vessels may not 
adjust course and speed until the delphinoid cetaceans have moved 
beyond 50 m and/or the abeam of the underway vessel;
    (vii) All vessels shall maintain a separation distance of 50 m (164 
ft) or greater from any sighted pinniped; and
    (viii) All vessels underway shall not divert or alter course in 
order to approach any whale, delphinoid cetacean, or pinniped. Any 
vessel underway will avoid excessive speed or abrupt changes in 
direction to avoid injury to the sighted cetacean or pinniped.
    (ix) The vessel operator shall comply with 10 knot (18.5 km/hr) or 
less speed restrictions in any Seasonal Management Area per NMFS 
guidance.
    (x) If NMFS should establish a Dynamic Management Area (DMA) in the 
area of the survey, within 24 hours of the establishment of the DMA, 
DWW shall contact the NMFS Office of Protected Resources to determine 
whether survey location and/or activities should be altered to avoid 
North Atlantic right whales.
    5. Monitoring Requirements--The Holder of this Authorization is 
required to conduct marine mammal visual monitoring and passive 
acoustic monitoring (PAM) during geophysical survey activity. 
Monitoring shall be conducted in accordance with the following 
requirements:
    (a) A minimum of four NMFS-approved PSOs and a minimum of two 
certified (PAM) operator(s), operating in shifts, shall be employed by 
DWW during geophysical surveys.
    (b) Observations shall take place from the highest available 
vantage point on the survey vessel. General 360-degree scanning shall 
occur during the monitoring periods, and target scanning by PSOs will 
occur when alerted of a marine mammal presence.
    (c) PSOs shall be equipped with binoculars and have the ability to 
estimate distances to marine mammals located in proximity to the vessel 
and/or Exclusion Zones using range finders. Reticulated binoculars will 
also be available to PSOs for use as appropriate based on conditions 
and visibility to support the sighting and monitoring of marine 
species.
    (d) PAM shall be used during nighttime geophysical survey

[[Page 19735]]

operations. The PAM system shall consist of an array of hydrophones 
with both broadband (sampling mid-range frequencies of 2 kHz to 200 
kHz) and at least one low-frequency hydrophone (sampling range 
frequencies of 75 Hz to 30 kHz). PAM operators shall communicate 
detections or vocalizations to the Lead PSO on duty who shall ensure 
the implementation of the appropriate mitigation measure.
    (e) During night surveys, night-vision equipment with infrared 
light-emitting diode spotlights and/or infrared video monitoring shall 
be used in addition to PAM. Specifications for night-vision equipment 
shall be provided to NMFS for review and acceptance prior to start of 
surveys.
    (f) PSOs and PAM operators shall work in shifts such that no one 
monitor will work more than 4 consecutive hours without a 2 hour break 
or longer than 12 hours during any 24-hour period. During daylight 
hours the PSOs shall rotate in shifts of 1 on and 3 off, and while 
during nighttime operations PSOs shall work in pairs.
    (g) PAM operators shall also be on call as necessary during daytime 
operations should visual observations become impaired.
    (h) Position data shall be recorded using hand-held or vessel 
global positioning system (GPS) units for each sighting.
    (i) A briefing shall be conducted between survey supervisors and 
crews, PSOs, and DWW to establish responsibilities of each party, 
define chains of command, discuss communication procedures, provide an 
overview of monitoring purposes, and review operational procedures.
    (j) DWW shall provide resumes of all proposed PSOs and PAM 
operators (including alternates) to NMFS for review and approval at 
least 45 days prior to the start of survey operations.
    (k) PSO Qualifications shall include completion of a PSO training 
course and documented field experience on a marine mammal observation 
vessel and/or aerial surveys.
    (a) Data on all PAM/PSO observations shall be recorded based on 
standard PSO collection requirements. PSOs must use standardized data 
forms, whether hard copy or electronic. The following information shall 
be reported:
    (i) PSO names and affiliations.
    (ii) Dates of departures and returns to port with port name.
    (iii) Dates and times (Greenwich Mean Time) of survey effort and 
times corresponding with PSO effort.
    (iv) Vessel location (latitude/longitude) when survey effort begins 
and ends; vessel location at beginning and end of visual PSO duty 
shifts.
    (v) Vessel heading and speed at beginning and end of visual PSO 
duty shifts and upon any line change.
    (vi) Environmental conditions while on visual survey (at beginning 
and end of PSO shift and whenever conditions change significantly), 
including wind speed and direction, Beaufort sea state, Beaufort wind 
force, swell height, weather conditions, cloud cover, sun glare, and 
overall visibility to the horizon.
    (vii) Factors that may be contributing to impaired observations 
during each PSO shift change or as needed as environmental conditions 
change (e.g., vessel traffic, equipment malfunctions).
    (viii) Survey activity information, such as acoustic source power 
output while in operation, number and volume of airguns operating in 
the array, tow depth of the array, and any other notes of significance 
(i.e., pre-ramp-up survey, ramp-up, shutdown, testing, shooting, ramp-
up completion, end of operations, streamers, etc.).
    (ix) If a marine mammal is sighted, the following information 
should be recorded:
    (A) Watch status (sighting made by PSO on/off effort, 
opportunistic, crew, alternate vessel/platform);
    (B) PSO who sighted the animal;
    (C) Time of sighting;
    (D) Vessel location at time of sighting;
    (E) Water depth;
    (F) Direction of vessel's travel (compass direction);
    (G) Direction of animal's travel relative to the vessel;
    (H) Pace of the animal;
    (I) Estimated distance to the animal and its heading relative to 
vessel at initial sighting;
    (J) Identification of the animal (e.g., genus/species, lowest 
possible taxonomic level, or unidentified); also note the composition 
of the group if there is a mix of species;
    (K) Estimated number of animals (high/low/best);
    (L) Estimated number of animals by cohort (adults, yearlings, 
juveniles, calves, group composition, etc.);
    (M) Description (as many distinguishing features as possible of 
each individual seen, including length, shape, color, pattern, scars or 
markings, shape and size of dorsal fin, shape of head, and blow 
characteristics);
    (N) Detailed behavior observations (e.g., number of blows, number 
of surfaces, breaching, spyhopping, diving, feeding, traveling; as 
explicit and detailed as possible; note any observed changes in 
behavior);
    (O) Animal's closest point of approach and/or closest distance from 
the center point of the acoustic source;
    (P) Platform activity at time of sighting (e.g., deploying, 
recovering, testing, data acquisition, other); and
    (Q) Description of any actions implemented in response to the 
sighting (e.g., delays, shutdown, ramp-up, speed or course alteration, 
etc.) and time and location of the action.
    6. Reporting--a technical report shall be provided to NMFS within 
90 days after completion of survey activities that fully documents the 
methods and monitoring protocols, summarizes the data recorded during 
monitoring, estimates the number of marine mammals that may have been 
taken during survey activities, describes the effectiveness of the 
various mitigation techniques (i.e. visual observations during day and 
night compared to PAM detections/operations) and provides an 
interpretation of the results and effectiveness of all monitoring 
tasks. Any recommendations made by NMFS shall be addressed in the final 
report prior to acceptance by NMFS.
    (a) Reporting injured or dead marine mammals:
    (i) In the event that the specified activity clearly causes the 
take of a marine mammal in a manner not prohibited by this IHA (if 
issued), such as serious injury or mortality, DWW shall immediately 
cease the specified activities and immediately report the incident to 
the NMFS Office of Protected Resources and the NMFS Greater Atlantic 
Stranding Coordinator. The report must include the following 
information:
    (A) Time, date, and location (latitude/longitude) of the incident;
    (B) Vessel's speed during and leading up to the incident;
    (C) Description of the incident;
    (D) Status of all sound source use in the 24 hours preceding the 
incident;
    (E) Water depth;
    (F) Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    (G) Description of all marine mammal observations in the 24 hours 
preceding the incident;
    (H) Species identification or description of the animal(s) 
involved;
    (I) Fate of the animal(s); and
    (J) Photographs or video footage of the animal(s).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS will work with DWW to 
determine what measures are necessary to minimize the likelihood of 
further prohibited take and ensure MMPA

[[Page 19736]]

compliance. DWW may not resume their activities until notified by NMFS.
    (ii) In the event that DWW discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (e.g., in less than 
a moderate state of decomposition), DWW shall immediately report the 
incident to the NMFS Office of Protected Resources and the NMFS Greater 
Atlantic Stranding Coordinator. The report must include the same 
information identified in condition 6(b)(i) of this IHA. Activities may 
continue while NMFS reviews the circumstances of the incident. NMFS 
will work with DWW to determine whether additional mitigation measures 
or modifications to the activities are appropriate.
    (iii) In the event that DWW discovers an injured or dead marine 
mammal, and the lead PSO determines that the injury or death is not 
associated with or related to the specified activities (e.g., 
previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), DWW shall report the incident to 
the NMFS Office of Protected Resources and the NMFS Greater Atlantic 
Stranding Coordinator within 24 hours of the discovery. DWW shall 
provide photographs or video footage or other documentation of the 
sighting to NMFS.
    7. This Authorization may be modified, suspended or withdrawn if 
the holder fails to abide by the conditions prescribed herein, or if 
NMFS determines the authorized taking is having more than a negligible 
impact on the species or stock of affected marine mammals.

Request for Public Comments

    We request comment on our analyses, the draft authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed marine 
site characterization surveys. Please include with your comments any 
supporting data or literature citations to help inform our final 
decision on the request for MMPA authorization.
    On a case-by-case basis, NMFS may issue a one-year renewal IHA 
without additional notice when (1) another year of identical or nearly 
identical activities as described in the Specified Activities section 
is planned, or (2) the activities would not be completed by the time 
the IHA expires and renewal would allow completion of the activities 
beyond that described in the Dates and Duration section, provided all 
of the following conditions are met:
     A request for renewal is received no later than 60 days 
prior to expiration of the current IHA.
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted beyond the 
initial dates either are identical to the previously analyzed 
activities or include changes so minor (e.g., reduction in pile size) 
that the changes do not affect the previous analyses, take estimates, 
or mitigation and monitoring requirements.
    (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 remain the same and appropriate, 
and the original findings remain valid.

    Dated: April 30, 2018.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2018-09481 Filed 5-3-18; 8:45 am]
 BILLING CODE 3510-22-P