Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Shallow Geohazard Survey in the Beaufort Sea, Alaska, 27901-27925 [2015-11701]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 80, Number 94 (Friday, May 15, 2015)]
[Notices]
[Pages 27901-27925]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-11701]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XD870


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Shallow Geohazard Survey in the 
Beaufort Sea, Alaska

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 received an application from Hilcorp Alaska, LLC. 
(Hilcorp) for an Incidental Harassment Authorization (IHA) to take 
marine mammals, by harassment, incidental to shallow geohazard survey 
in the Beaufort Sea, Alaska. Pursuant to the Marine Mammal Protection 
Act (MMPA), NMFS is requesting comments on its proposal to issue an IHA 
to Hilcorp to take, by Level B harassment only, 6 species of marine 
mammals during the specified activity.

DATES: Comments and information must be received no later than June 15, 
2015.

ADDRESSES: Comments on the application should be addressed to Jolie 
Harrison, Chief, Permits and Conservation Division, Office of Protected 
Resources, National Marine Fisheries Service, 1315 East-West Highway, 
Silver Spring, MD 20910. The mailbox address for providing email 
comments is ITP.Guan@noaa.gov. NMFS is not responsible for email 
comments sent to addresses other than the one provided here. Comments 
sent via email, including all attachments, must not exceed a 10-
megabyte file size.
    Instructions: All comments received are a part of the public record 
and will generally be posted to https://www.nmfs.noaa.gov/pr/permits/incidental.htm without change. All Personal Identifying Information 
(for example, name, address, etc.) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit Confidential 
Business Information or otherwise sensitive or protected information.
    A copy of the application, which contains several attachments, 
including Hilcorp's marine mammal mitigation and monitoring plan (4MP), 
used in this document may be obtained by writing to the address 
specified above, telephoning the contact listed below (see FOR FURTHER 
INFORMATION CONTACT), or visiting the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm. Documents cited in this 
notice may also be viewed, by appointment, during regular business 
hours, at the aforementioned address.

FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected 
Resources, NMFS, (301) 427-8401.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce 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.''
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment].

Summary of Request

    On December 1, 2014, NMFS received an application from Hilcorp for 
the taking of marine mammals incidental to shallow geohazard surveys in 
the Beaufort Sea. After receiving NMFS comments, Hilcorp submitted a 
revised IHA application on January 5, 2015. In addition, Hilcorp 
submitted a 4MP on January 21, 2015. NMFS determined that the 
application was adequate and complete on February 9, 2015.
    The proposed activity would occur between July 1 and September 30, 
2015. The actual survey is expected to be complete in 45 days, 
including weather and equipment downtime. Underwater noises generated 
from the sonar used for the survey are likely to result Level B 
harassment of individuals of 6 species of marine mammals.

Description of the Specified Activity

Overview

    Hilcorp plans to conduct a shallow geohazard survey and Strudel 
Scour survey with a transition zone component on state lands, and in 
federal and state waters of Foggy Island Bay in the Beaufort Sea during 
the open water season of 2015. The scope of this request is limited to 
the activities that will be conducted during the 2015 open water 
evaluation of the proposed Liberty field development.

Dates and Duration

    Hilcorp seeks incidental harassment authorization for the period 
July 1 to September 30, 2015. The survey is expected to take 
approximately 45 days

[[Page 27902]]

to complete, including weather and equipment downtime. About 25% of 
downtime is included in this total, so the actual number of days that 
equipment are expected to be operating is estimated at 34, based on a 
continuous 24-hr. operation.

Specified Geographic Region

    The project area of the proposed Liberty shallow geohazard survey 
lies within Foggy Island Bay as shown in Figure 1 of Hilcorp's IHA 
application. The project area is 2.5 mi\2\ in water depths ranging from 
3 to 20 ft.

Detailed Description of Activities

(1) Survey Designs
    The proposed sonar survey vessel (M/V Sidewinder or equivalent) is 
about 40 x 14 feet in size. The sub-bottom profilers and magnetometer 
will be deployed from the vessel. The echosounder and side scan sonar 
will be hull-mounted. No equipment will be placed on the sea floor as 
part of survey activities. Because of the extremely shallow project 
area, additional small vessel(s) may be utilized to safely extend 
vessel operations for data collection.
    The total planned survey lines are approximately 300 miles, not 
including turns and cross-lines. Data will be acquired along the subsea 
pipeline corridor area using the single-beam or multibeam echosounder, 
side scan sonar, sub-bottom profilers, and the magnetometer. Because of 
the shallow nature of the project area and small size of the vessel, 
systems will be towed in optimal groupings that best facilitate safe 
operations and data quality. As necessary, a small vessel may be used 
to extend data collection into shallow waters. Planned survey lines 
will be designed to acquire 150% side scan sonar data coverage or as 
mandated, with line spacing dependent upon water depth. A 300 m 
corridor around the centerline of the proposed pipeline area will be 
covered.
(2) Acoustic Sources

Multibeam Echo Sounder and Side Scan Sonar

    A single-beam or multibeam echosounder and side scan sonar will be 
used to obtain high accuracy information regarding bathymetry of the 
seafloor. For accurate object detection, a side scan sonar survey is 
required to complement a multibeam echosounder survey.
    The proposed multibeam echosounder operates at an rms source level 
of a maximum of 220 dB re 1 [mu]Pa @1 m. The multibeam echosounder 
emits high frequency (240 kHz) energy in a fan-shaped pattern of 
equidistant or equiangular beam spacing (Table 1). The beam width of 
the emitted sound energy in the along-track direction is 1.5 degrees, 
while the across track beam width is 1.8 degrees. The maximum ping rate 
of the multibeam echosounder is 40 Hz.
    The proposed single-beam echosounder operates at an rms source 
level of approximately 220 dB re 1 [mu]Pa @1 m (Table 1). The 
transducer selected uses a frequency of 210 kHz and has a ping rate of 
up to 20 Hz. The transducer's beam width is approximately 3 degrees.
    The proposed side scan sonar system will operate at about 400 kHz 
and 900 kHz. The rms source level is 215 dB re 1[mu]Pa @1 m. The sound 
energy is emitted in a narrow fan-shaped pattern, with a horizontal 
beam width of 0.45 degrees for 400 kHz and 0.25 degrees at 900 kHz, 
with a vertical beam width of 50 degrees (Table 1). The maximum ping 
rate is 75 Hz.

Sub-Bottom Profiler

    The proposed high-resolution sub-bottom profiler operates at an rms 
source level of 210db re 1 [mu]Pa @1 m. The proposed system emits 
energy in the frequency bands of 2 to 24 kHz. The beam width is 15 to 
24 degrees (Table 1). Typical pulse rate is between 3 and 10 Hz.
    The proposed low-resolution sub-bottom profiler operates at an rms 
source level of 212db re 1 [mu]Pa @1 m. This secondary sub-bottom 
profiler will be utilized as necessary to increase sub-bottom profile 
penetration. The proposed system emits energy in the frequency bands of 
1 to 4 kHz.

   Table 1--Source Characteristics of the Proposed Geophysical Survey Equipment To Be Used During the Liberty
                                                Geohazard Survey
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                                                                                                        Source
                                    Sample         Operating     Along track beam    Across track     level (dB
          Equipment            equipment model     frequency           width          beam width     re 1 [mu]Pa
                                     type                                                             @1 m, rms)
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Multibeam echosounder........  Reson 7101 SV..  240 kHz........  1.5[deg]........  1.8[deg]........          220
Single-beam echosounder......  Odom...........  210 kHz........  3[deg]..........  3[deg]..........          220
Side scan sonar..............  Edgetech 4125..  400 kHz/900 kHz  0.5[deg]........  50[deg].........          215
High resolution (CHIRP) sub-   Edgetech 3200..  2 to 24 kHz....  15[deg] to        15[deg] to                210
 bottom profiler.                                                 24[deg].          24[deg].
Low resolution sub-bottom      Applied          1 to 4 kHz.....  n/a.............  n/a.............          212
 profiler.                      Acoustics
                                AA251.
Alternative multibeam          Norbit IWBMS...  400 kHz........  1.9[deg]........  0.9[deg]........          218
 echosounder.
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Description of Marine Mammals in the Area of the Specified Activity

    The Beaufort Sea supports a diverse assemblage of marine mammals. 
Table 2 lists the 12 marine mammal species under NMFS jurisdiction with 
confirmed or possible occurrence in the proposed project area.

[[Page 27903]]

[GRAPHIC] [TIFF OMITTED] TN15MY15.002

    The highlighted (grayed out) species in Table 2 are so rarely 
sighted in the proposed project area that take is unlikely. Minke 
whales are relatively common in the Bering and southern Chukchi Seas 
and have recently also been sighted in the northeastern Chukchi Sea 
(Aerts et al., 2013; Clarke et al., 2013). Minke whales are rare in the 
Beaufort Sea. They have not been reported in the Beaufort Sea during 
the Bowhead Whale Aerial Survey Project/Aerial Surveys of Arctic Marine 
Mammals (BWASP/ASAMM) surveys (Clarke et al., 2011, 2012; 2013; Monnet 
and Treacy, 2005), and there was only one observation in 2007 during 
vessel-based surveys in the region (Funk et al., 2010). Humpback whales 
have not generally been found in the Arctic Ocean. However, subsistence 
hunters have spotted humpback whales in low numbers around Barrow, and 
there have been several confirmed sightings of humpback whales in the 
northeastern Chukchi Sea in recent years (Aerts et al., 2013; Clarke et 
al., 2013). The first confirmed sighting of a humpback whale in the 
Beaufort Sea was recorded in August 2007 (Hashagen et al., 2009), when 
a cow and calf were observed 54 mi east of Point Barrow. No additional 
sightings have been documented in the

[[Page 27904]]

Beaufort Sea. Narwhal are common in the waters of northern Canada, west 
Greenland, and in the European Arctic, but rarely occur in the Beaufort 
Sea (COSEWIC, 2004). Only a handful of sightings have occurred in 
Alaskan waters (Allen and Angliss, 2013). These three species are not 
considered further in this proposed IHA notice. Both the walrus and the 
polar bear could occur in the U.S. Beaufort Sea; however, these species 
are managed by the U.S. Fish and Wildlife Service (USFWS) and are not 
considered further in this Notice of Proposed IHA.
    The Beaufort Sea is a main corridor of the bowhead whale migration 
route. The main migration periods occur in spring from April to June 
and in fall from late August/early September through October to early 
November. During the fall migration, several locations in the U.S. 
Beaufort Sea serve as feeding grounds for bowhead whales. Small numbers 
of bowhead whales that remain in the U.S. Arctic Ocean during summer 
also feed in these areas. The U.S. Beaufort Sea is not a main feeding 
or calving area for any other cetacean species. Ringed seals breed and 
pup in the Beaufort Sea; however, this does not occur during the summer 
or early fall. Further information on the biology and local 
distribution of these species can be found in Hilcorp's application 
(see ADDRESSES) and the NMFS Marine Mammal Stock Assessment Reports, 
which are available online at: https://www.nmfs.noaa.gov/pr/species/.

Potential Effects of the Specified Activity on Marine Mammals

    This section includes a summary and discussion of the ways that the 
types of stressors associated with the specified activity (e.g., sonar 
sources and vessel movement) have been observed to or are thought to 
impact marine mammals. This section may include a discussion of known 
effects that do not rise to the level of an MMPA take (for example, 
with acoustics, we may include a discussion of studies that showed 
animals not reacting at all to sound or exhibiting barely measurable 
avoidance). The discussion may also include reactions that we consider 
to rise to the level of a take and those that we do not consider to 
rise to the level of a take. This section is intended as a background 
of potential effects and does not consider either the specific manner 
in which this activity will be carried out or the mitigation that will 
be implemented or how either of those will shape the anticipated 
impacts from this specific activity. The ``Estimated Take by Incidental 
Harassment'' section later in this document will include a quantitative 
analysis of the number of individuals that are expected to be taken by 
this activity. The ``Negligible Impact Analysis'' section will include 
the analysis of how this specific activity will impact marine mammals 
and will consider the content of this section, the ``Estimated Take by 
Incidental Harassment'' section, the ``Proposed Mitigation'' section, 
and the ``Anticipated Effects on Marine Mammal Habitat'' section to 
draw conclusions regarding the likely impacts of this activity on the 
reproductive success or survivorship of individuals and from that on 
the affected marine mammal populations or stocks.

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 hertz (Hz) or kilohertz (kHz), while sound 
level describes the sound's intensity and is measured in decibels (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]Pa'' and ``re: 1 
[micro]Pa,'' respectively. Root mean square (RMS) is the quadratic mean 
sound pressure over the duration of an impulse. RMS is calculated by 
squaring all of the sound amplitudes, averaging the squares, and then 
taking the square root of the average (Urick, 1975). RMS accounts for 
both positive and negative values; squaring the pressures makes all 
values positive so that they may be accounted for in the summation of 
pressure levels. This measurement is often used in the context of 
discussing behavioral effects, in part, because behavioral effects, 
which often result from auditory cues, may be better expressed through 
averaged units rather than by peak pressures.

Acoustic Impacts

    When considering the influence of various kinds of sound on the 
marine environment, it is necessary to understand that different kinds 
of marine life are sensitive to different frequencies of sound. Based 
on available behavioral data, audiograms have been derived using 
auditory evoked potentials, anatomical modeling, and other data, 
Southall et al. (2007) designate ``functional hearing groups'' for 
marine mammals and estimate the lower and upper frequencies of 
functional hearing of the groups. The functional groups and the 
associated frequencies are indicated below (though animals are less 
sensitive to sounds at the outer edge of their functional range and 
most sensitive to sounds of frequencies within a smaller range 
somewhere in the middle of their functional hearing range):
     Low frequency cetaceans (13 species of mysticetes): 
Functional hearing is estimated to occur between approximately 7 Hz and 
30 kHz;
     Mid-frequency cetaceans (32 species of dolphins, six 
species of larger toothed whales, and 19 species of beaked and 
bottlenose whales): Functional hearing is estimated to occur between 
approximately 150 Hz and 160 kHz;
     High frequency cetaceans (eight species of true porpoises, 
six species of river dolphins, Kogia, the franciscana, and four species 
of cephalorhynchids): Functional hearing is estimated to occur between 
approximately 200 Hz and 180 kHz;
     Phocid pinnipeds in water: Functional hearing is estimated 
to occur between approximately 75 Hz and 100 kHz; and
     Otariid pinnipeds in water: Functional hearing is 
estimated to occur between approximately 100 Hz and 40 kHz.
    As mentioned previously in this document, six marine mammal species 
(three cetaceans and three phocid pinnipeds) may occur in the proposed 
shallow hazard survey area. Of the three cetacean species likely to 
occur in the proposed project area and for which take is requested, two 
are classified as low-frequency cetaceans (i.e., bowhead and gray 
whales), the beluga whale is classified as mid-frequency cetacean 
(Southall et al., 2007). A species functional hearing group is a 
consideration when we analyze the effects of exposure to sound on 
marine mammals.
    Although the analysis of impacts of underwater sound on marine 
mammals described below heavily based on studies from seismic airgun 
noises, Hilcorp's proposed shallow geohazard survey does not plan to 
use airguns. Therefore, the potential impacts to marine mammals are 
expected to be much lower. The reason that the analysis includes airgun 
impact research is because there are few studies on impacts of marine 
mammals from

[[Page 27905]]

marine surveys conducted by sonar equipment.
1. Tolerance
    Numerous studies have shown that underwater sounds from industry 
activities are often readily detectable by marine mammals in the water 
at distances of many kilometers. Numerous studies have also shown that 
marine mammals at distances more than a few kilometers away often show 
no apparent response to industry activities of various types (Miller et 
al., 2005; Bain and Williams, 2006). 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 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). 
Weir (2008) observed marine mammal responses to seismic pulses from a 
24 airgun array firing a total volume of either 5,085 in\3\ or 3,147 
in\3\ in Angolan waters between August 2004 and May 2005. Weir recorded 
a total of 207 sightings of humpback whales (n = 66), sperm whales (n = 
124), and Atlantic spotted dolphins (n = 17) and reported that there 
were no significant differences in encounter rates (sightings/hr) for 
humpback and sperm whales according to the airgun array's operational 
status (i.e., active versus silent). However, the current geohazard 
survey will not use airguns. In general, pinnipeds and small 
odontocetes seem to be more tolerant of exposure to some types of 
underwater sound than are baleen whales. Richardson et al. (1995) found 
that vessel noise does not seem to strongly 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.
2. Masking
    Masking is the obscuring of sounds of interest by other sounds, 
often at similar frequencies. Marine mammals use acoustic signals for a 
variety of purposes, which differ among species, but include 
communication between individuals, navigation, foraging, reproduction, 
avoiding predators, and learning about their environment (Erbe and 
Farmer, 2000). Masking, or auditory interference, generally occurs when 
sounds in the environment are louder than, and of a similar frequency 
as, auditory signals an animal is trying to receive. Masking is a 
phenomenon that affects animals that are trying to receive acoustic 
information about their environment, including sounds from other 
members of their species, predators, prey, and sounds that allow them 
to orient in their environment. Masking these acoustic signals can 
disturb the behavior of individual animals, groups of animals, or 
entire populations.
    Masking occurs when anthropogenic sounds and signals (that the 
animal utilizes) overlap at both spectral and temporal scales. For the 
sonar sound generated from the proposed shallow geohazard survey, sound 
will consist of broadband (2-24 kHz) pulses with extremely short 
durations (less than one second). There is little concern regarding 
masking near the sound source due to the brief duration of these pulses 
and relatively longer silence between the pulses. However, at long 
distances (over tens of kilometers away), due to multipath propagation 
and reverberation, the durations of airgun pulses can be ``stretched'' 
to seconds with long decays (Madsen et al., 2006), although the 
intensity of the sound is greatly reduced.
3. Behavioral Disturbance
    Marine mammals may behaviorally react when exposed to anthropogenic 
sound. These behavioral reactions are often shown as: Changing 
durations of surfacing and dives, number of blows per surfacing, or 
moving direction and/or speed; reduced/increased vocal activities; 
changing/cessation of certain behavioral activities (such as 
socializing or feeding); visible startle response or aggressive 
behavior (such as tail/fluke slapping or jaw clapping); avoidance of 
areas where sound sources are located; and/or flight responses (e.g., 
pinnipeds flushing into water from haulouts or rookeries).
    The biological significance of many of these behavioral 
disturbances is difficult to predict, especially if the detected 
disturbances appear minor. However, the consequences of behavioral 
modification have the potential to be biologically significant if the 
change affects growth, survival, or reproduction. Examples of 
significant behavioral modifications include:
     Drastic change in diving/surfacing patterns (such as those 
thought to be causing beaked whale stranding due to exposure to 
military mid-frequency tactical sonar);
     Habitat abandonment due to loss of desirable acoustic 
environment; and
     Cessation of feeding or social interaction.
    The onset of behavioral disturbance from anthropogenic noise 
depends on both external factors (characteristics of noise sources and 
their paths) and the receiving animals (hearing, motivation, 
experience, demography, current activity, reproductive state) and is 
also difficult to predict (Gordon et al., 2004; Southall et al., 2007; 
Ellison et al., 2011).
    Mysticetes: Baleen whales generally tend to avoid operating 
airguns, but avoidance radii are quite variable. Whales are often 
reported to show no overt reactions to pulses from large arrays of 
airguns at distances beyond a few kilometers, even though the airgun 
pulses remain well above ambient noise levels out to much greater 
distances (Miller et al., 2005). However, baleen whales exposed to 
strong noise pulses often react by deviating from their normal 
migration route (Richardson et al., 1999). Migrating gray and bowhead 
whales were observed avoiding the sound source by displacing their 
migration route to varying degrees but within the natural boundaries of 
the migration corridors (Schick and Urban, 2000; Richardson et al., 
1999). Baleen whale responses to pulsed sound however may depend on the 
type of activity in which the whales are engaged. Some evidence 
suggests that feeding bowhead whales may be more tolerant of underwater 
sound than migrating bowheads (Miller et al., 2005; Lyons et al., 2009; 
Christie et al., 2010).
    Results of studies of gray, bowhead, and humpback whales have 
determined that received levels of pulses in the 160-170 dB re 1 
[micro]Pa rms range seem to cause obvious avoidance behavior in a 
substantial fraction of the animals exposed. In many areas, seismic 
pulses from large arrays of airguns diminish to those levels at 
distances ranging from 2.8-9 mi (4.5-14.5 km) from the source. Baleen 
whales within those distances may show avoidance or other strong 
disturbance reactions to the airgun array. Subtle behavioral changes 
sometimes become evident at somewhat lower received levels, and recent 
studies have shown that some species of baleen whales, notably bowhead 
and humpback whales, at times show strong avoidance at received levels 
lower than 160-170 dB re 1 [mu]Pa rms. Bowhead whales migrating west 
across the Alaskan Beaufort Sea in autumn, in particular, are unusually 
responsive, with avoidance occurring out to distances of 12.4-18.6 mi 
(20-30 km) from a medium-sized airgun source (Miller et al., 1999; 
Richardson et al., 1999). However, more recent research

[[Page 27906]]

on bowhead whales (Miller et al., 2005) corroborates earlier evidence 
that, during the summer feeding season, bowheads are not as sensitive 
to seismic sources. In summer, bowheads typically begin to show 
avoidance reactions at a received level of about 160-170 dB re 1 
[micro]Pa rms (Richardson et al., 1986; Ljungblad et al., 1988; Miller 
et al., 2005).
    Malme et al. (1986) studied the responses of feeding eastern gray 
whales to pulses from a single 100 in\3\ airgun off St. Lawrence Island 
in the northern Bering Sea. They estimated, based on small sample 
sizes, that 50% of feeding gray whales ceased feeding at an average 
received pressure level of 173 dB re 1 [micro]Pa on an (approximate) 
rms basis, and that 10% of feeding whales interrupted feeding at 
received levels of 163 dB. Those findings were generally consistent 
with the results of experiments conducted on larger numbers of gray 
whales that were migrating along the California coast and on 
observations of the distribution of feeding Western Pacific gray whales 
off Sakhalin Island, Russia, during a seismic survey (Yazvenko et al., 
2007).
    Data on short-term reactions (or lack of reactions) of cetaceans to 
impulsive noises do not necessarily provide information about long-term 
effects. While it is not certain whether impulsive noises affect 
reproductive rate or distribution and habitat use in subsequent days or 
years, certain species have continued to use areas ensonified by 
airguns and have continued to increase in number despite successive 
years of anthropogenic activity in the area. Gray whales continued to 
migrate annually along the west coast of North America despite 
intermittent seismic exploration and much ship traffic in that area for 
decades (Appendix A in Malme et al., 1984). Bowhead whales continued to 
travel to the eastern Beaufort Sea each summer despite seismic 
exploration in their summer and autumn range for many years (Richardson 
et al., 1987). Populations of both gray whales and bowhead whales grew 
substantially during this time. In any event, the proposed survey will 
occur in summer (July through late August) when most bowhead whales are 
commonly feeding in the Mackenzie River Delta, Canada.
    Odontocetes: Few systematic data are available describing reactions 
of toothed whales to noise pulses. However, systematic work on sperm 
whales is underway, and there is an increasing amount of information 
about responses of various odontocetes to seismic surveys based on 
monitoring studies (e.g., Stone, 2003). Miller et al. (2009) conducted 
at-sea experiments where reactions of sperm whales were monitored 
through the use of controlled sound exposure experiments from large 
airgun arrays consisting of 20-guns and 31-guns. Of 8 sperm whales 
observed, none changed their behavior when exposed to either a ramp-up 
at 4-8 mi (7-13 km) or full array exposures at 0.6-8 mi (1-13 km).
    Seismic operators and marine mammal observers sometimes see 
dolphins and other small toothed whales near operating airgun arrays, 
but, in general, there seems to be a tendency for most delphinids to 
show some limited avoidance of seismic vessels operating large airgun 
systems. However, some dolphins seem to be attracted to the seismic 
vessel and floats, and some ride the bow wave of the seismic vessel 
even when large arrays of airguns are firing. Nonetheless, there have 
been indications that small toothed whales sometimes move away or 
maintain a somewhat greater distance from the vessel when a large array 
of airguns is operating than when it is silent (e.g., 1998; Stone, 
2003). The beluga may be a species that (at least in certain geographic 
areas) shows long-distance avoidance of seismic vessels. Aerial surveys 
during seismic operations in the southeastern Beaufort Sea recorded 
much lower sighting rates of beluga whales within 10-20 km (6.2-12.4 
mi) of an active seismic vessel. These results were consistent with the 
low number of beluga sightings reported by observers aboard the seismic 
vessel, suggesting that some belugas might have been avoiding the 
seismic operations at distances of 10-20 km (6.2-12.4 mi) (Miller et 
al., 2005).
    Captive bottlenose dolphins and (of more relevance in this project) 
beluga whales exhibit changes in behavior when exposed to strong pulsed 
sounds similar in duration to those typically used in seismic surveys 
(Finneran et al., 2002, 2005). However, the animals tolerated high 
received levels of sound (pk-pk level >200 dB re 1 [mu]Pa) before 
exhibiting aversive behaviors.
    Observers stationed on seismic vessels operating off the United 
Kingdom from 1997-2000 have provided data on the occurrence and 
behavior of various toothed whales exposed to seismic pulses (Stone, 
2003; Gordon et al., 2004). Killer whales were found to be 
significantly farther from large airgun arrays during periods of 
shooting compared with periods of no shooting. The displacement of the 
median distance from the array was approximately 0.5 km (0.3 mi) or 
more. Killer whales also appear to be more tolerant of seismic shooting 
in deeper water.
    Reactions of toothed whales to large arrays of airguns are variable 
and, at least for delphinids, seem to be confined to a smaller radius 
than has been observed for mysticetes. However, based on the limited 
existing evidence, belugas should not be grouped with delphinids in the 
``less responsive'' category.
    Pinnipeds: Pinnipeds are not likely to show a strong avoidance 
reaction to the airgun sources proposed for use. Visual monitoring from 
seismic vessels has shown only slight (if any) avoidance of airguns by 
pinnipeds and only slight (if any) changes in behavior. Monitoring work 
in the Alaskan Beaufort Sea during 1996-2001 provided considerable 
information regarding the behavior of Arctic ice seals exposed to 
seismic pulses (Harris et al., 2001; Moulton and Lawson, 2002). These 
seismic projects usually involved arrays of 6 to 16 airguns with total 
volumes of 560 to 1,500 in\3\. The combined results suggest that some 
seals avoid the immediate area around seismic vessels. In most survey 
years, ringed seal sightings tended to be farther away from the seismic 
vessel when the airguns were operating than when they were not (Moulton 
and Lawson, 2002). However, these avoidance movements were relatively 
small, on the order of 100 m (328 ft) to a few hundreds of meters, and 
many seals remained within 100-200 m (328-656 ft) of the trackline as 
the operating airgun array passed by. Seal sighting rates at the water 
surface were lower during airgun array operations than during no-airgun 
periods in each survey year except 1997. Similarly, seals are often 
very tolerant of pulsed sounds from seal-scaring devices (Richardson et 
al., 1995). However, initial telemetry work suggests that avoidance and 
other behavioral reactions by two other species of seals to small 
airgun sources may at times be stronger than evident to date from 
visual studies of pinniped reactions to airguns (Thompson et al., 
1998). Even if reactions of the species occurring in the present study 
area are as strong as those evident in the telemetry study, reactions 
are expected to be confined to relatively small distances and 
durations, with no long-term effects on pinniped individuals or 
populations.
4. Threshold Shift (Noise-Induced Loss of Hearing)
    When animals exhibit reduced hearing sensitivity (i.e., sounds must 
be louder for an animal to detect them) following exposure to an 
intense sound or sound for long duration, it is referred

[[Page 27907]]

to as a noise-induced threshold shift (TS). An animal can experience 
temporary threshold shift (TTS) or permanent threshold shift (PTS). TTS 
can last from minutes or hours to days (i.e., there is complete 
recovery), can occur in specific frequency ranges (i.e., an animal 
might only have a temporary loss of hearing sensitivity between the 
frequencies of 1 and 10 kHz), and can be of varying amounts (for 
example, an animal's hearing sensitivity might be reduced initially by 
only 6 dB or reduced by 30 dB). PTS is permanent, but some recovery is 
possible. PTS can also occur in a specific frequency range and amount 
as mentioned above for TTS.
    The following physiological mechanisms are thought to play a role 
in inducing auditory TS: Effects to sensory hair cells in the inner ear 
that reduce their sensitivity, modification of the chemical environment 
within the sensory cells, residual muscular activity in the middle ear, 
displacement of certain inner ear membranes, increased blood flow, and 
post-stimulatory reduction in both efferent and sensory neural output 
(Southall et al., 2007). The amplitude, duration, frequency, temporal 
pattern, and energy distribution of sound exposure all can affect the 
amount of associated TS and the frequency range in which it occurs. As 
amplitude and duration of sound exposure increase, so, generally, does 
the amount of TS, along with the recovery time. For intermittent 
sounds, less TS could occur than compared to a continuous exposure with 
the same energy (some recovery could occur between intermittent 
exposures depending on the duty cycle between sounds) (Ward, 1997). For 
example, one short but loud (higher SPL) sound exposure may induce the 
same impairment as one longer but softer sound, which in turn may cause 
more impairment than a series of several intermittent softer sounds 
with the same total energy (Ward, 1997). Additionally, though TTS is 
temporary, prolonged exposure to sounds strong enough to elicit TTS, or 
shorter-term exposure to sound levels well above the TTS threshold, can 
cause PTS, at least in terrestrial mammals.
    PTS is considered auditory injury (Southall et al., 2007). 
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).
    Although the published body of scientific literature contains 
numerous theoretical studies and discussion papers on hearing 
impairments that can occur with exposure to a loud sound, only a few 
studies provide empirical information on the levels at which noise-
induced loss in hearing sensitivity occurs in nonhuman animals. For 
marine mammals, published data are limited to the captive bottlenose 
dolphin, beluga, harbor porpoise, and Yangtze finless porpoise 
(Finneran et al., 2000, 2002, 2003, 2005, 2007; Finneran and Schlundt, 
2010; Lucke et al., 2009; Mooney et al., 2009; Popov et al., 2011a, 
2011b; Kastelein et al., 2012a; Schlundt et al., 2006; Nachtigall et 
al., 2003, 2004). For pinnipeds in water, data are limited to 
measurements of TTS in harbor seals, an elephant seal, and California 
sea lions (Kastak et al., 2005; Kastelein et al., 2012b).
    Marine mammal hearing plays a critical role in communication with 
conspecifics, and 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 
(similar to those discussed in auditory masking, below). 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 occurs 
during a time 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 time when communication is critical 
for successful mother/calf interactions could have more serious 
impacts. Also, depending on the degree and frequency range, the effects 
of PTS on an animal could range in severity, although it is considered 
generally more serious because it is a permanent condition. Of note, 
reduced hearing sensitivity as a simple function of aging has been 
observed in marine mammals, as well as humans and other taxa (Southall 
et al., 2007), so we can infer that strategies exist for coping with 
this condition to some degree, though likely not without cost.
5. Non-Auditory Physical Effects
    Non-auditory physical effects might occur in marine mammals exposed 
to strong underwater sound. Possible types of non-auditory 
physiological effects or injuries that theoretically might occur in 
mammals close to a strong sound source include stress, neurological 
effects, bubble formation, and other types of organ or tissue damage. 
Some marine mammal species (i.e., beaked whales) may be especially 
susceptible to injury and/or stranding when exposed to strong pulsed 
sounds.
    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; Sapolsky et al., 2005; 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 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 effects on an animal's welfare.
    An animal's third line of defense to stressors involves its 
neuroendocrine or sympathetic nervous systems; the system that has 
received the most study has been the hypothalmus-pituitary-adrenal 
system (also known as the HPA axis in mammals or the hypothalamus-
pituitary-interrenal axis in fish and some reptiles). Unlike stress 
responses associated with the autonomic nervous system, virtually all 
neuroendocrine 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), 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

[[Page 27908]]

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 
functions, which impair 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 fitness will suffer. In these cases, 
the animals will have entered a pre-pathological or pathological state 
which is called ``distress'' (sensu Seyle, 1950) or ``allostatic 
loading'' (sensu 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 experiment; 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). Although no information has been collected on the physiological 
responses of marine mammals to anthropogenic sound exposure, studies of 
other marine animals and terrestrial animals would 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 anthropogenic sounds.
    For example, Jansen (1998) reported on the relationship between 
acoustic exposures and physiological responses that are indicative of 
stress responses in humans (e.g., 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) 
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 communicate with conspecifics. 
Although empirical information on the relationship between sensory 
impairment (TTS, PTS, and acoustic masking) on marine mammals remains 
limited, we assume that reducing a marine mammal's ability to gather 
information about its environment and communicate with other members of 
its species would induce stress, based on data that terrestrial animals 
exhibit those responses under similar conditions (NRC, 2003) and 
because marine mammals 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. 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), NMFS also assumes that stress 
responses could 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.
    Resonance effects (Gentry, 2002) and direct noise-induced bubble 
formations (Crum et al., 2005) are implausible in the case of exposure 
to an impulsive broadband source like an airgun array. If seismic 
surveys disrupt diving patterns of deep-diving species, this might 
result in bubble formation and a form of the bends, as speculated to 
occur in beaked whales exposed to sonar. However, there is no specific 
evidence of this upon exposure to low-intensity civilian sonar pulses. 
Additionally, no beaked whale species occur in the proposed project 
area.
    In general, very little is known about the potential for strong, 
anthropogenic underwater sounds to cause non-auditory physical effects 
in marine mammals. Such effects, if they occur at all, would presumably 
be limited to short distances and to activities that extend over a 
prolonged period. The available data do not allow identification of a 
specific exposure level above which non-auditory effects can be 
expected (Southall et al., 2007) or any meaningful quantitative 
predictions of the numbers (if any) of marine mammals that might be 
affected in those ways. There is no definitive evidence that any of 
these effects occur even for marine mammals in close proximity to large 
arrays of airguns, which are not proposed for use during this program. 
In addition, marine mammals that show behavioral avoidance of industry 
activities, including bowheads, belugas, and some pinnipeds, are 
especially unlikely to incur non-auditory impairment or other physical 
effects.
6. Stranding and Mortality
    Marine mammals close to underwater detonations of high explosive 
can be killed or severely injured, and the auditory organs are 
especially susceptible to injury (Ketten et al., 1993; Ketten, 1995). 
Airgun pulses are less energetic and their peak amplitudes have slower 
rise times. To date, there is no evidence that serious injury, death, 
or stranding by marine mammals can occur from exposure to airgun 
pulses, even in the case of large airgun arrays. Additionally, 
Hilcorp's project will use low-intensity sonar equipment in shallow 
water. NMFS does not expect any marine mammals will incur injury or 
mortality in the shallow waters off Beaufort Sea or strand as a result 
of the proposed geohazard survey.

Vessel Impacts

    Vessel activity and noise associated with vessel activity will 
temporarily increase in the action area during Hilcorp's shallow 
geohazard survey as a result of the operation of 1-2 vessels. To 
minimize the effects of vessels and noise associated with vessel 
activity, Hilcorp will alter speed if a marine mammal gets too close to 
a vessel. In addition, source vessels will be operating at slow speed 
(4-5 knots) when conducting surveys. Marine mammal monitoring observers 
will alert vessel captains as animals are detected to ensure safe and 
effective measures are applied to avoid coming into direct contact with 
marine mammals. Therefore, NMFS neither anticipates nor

[[Page 27909]]

authorizes takes of marine mammals from ship strikes.
    McCauley et al. (1996) reported several cases of humpback whales 
responding to vessels in Hervey Bay, Australia. Results indicated clear 
avoidance at received levels between 118 to 124 dB in three cases for 
which response and received levels were observed/measured.
    Palka and Hammond (2001) analyzed line transect census data in 
which the orientation and distance off transect line were reported for 
large numbers of minke whales. The authors developed a method to 
account for effects of animal movement in response to sighting 
platforms. Minor changes in locomotion speed, direction, and/or diving 
profile were reported at ranges from 1,847 to 2,352 ft (563 to 717 m) 
at received levels of 110 to 120 dB.
    Odontocetes, such as beluga whales, killer whales, and harbor 
porpoises, often show tolerance to vessel activity; however, they may 
react at long distances if they are confined by ice, shallow water, or 
were previously harassed by vessels (Richardson et al., 1995). Beluga 
whale response to vessel noise varies greatly from tolerance to extreme 
sensitivity depending on the activity of the whale and previous 
experience with vessels (Richardson et al., 1995). Reactions to vessels 
depends on whale activities and experience, habitat, boat type, and 
boat behavior (Richardson et al., 1995) and may include behavioral 
responses, such as altered headings or avoidance (Blane and Jaakson, 
1994; Erbe and Farmer, 2000); fast swimming; changes in vocalizations 
(Lesage et al., 1999; Scheifele et al., 2005); and changes in dive, 
surfacing, and respiration patterns.
    There are few data published on pinniped responses to vessel 
activity, and most of the information is anecdotal (Richardson et al., 
1995). Generally, sea lions in water show tolerance to close and 
frequently approaching vessels and sometimes show interest in fishing 
vessels. They are less tolerant when hauled out on land; however, they 
rarely react unless the vessel approaches within 100-200 m (Richardson 
et al., 1995).
    The addition of the vessels and noise due to vessel operations 
associated with the shallow geohazard survey is not expected to have 
effects that could cause significant or long-term consequences for 
individual marine mammals or their populations.

Anticipated Effects on Marine Mammal Habitat

    The primary potential impacts to marine mammal habitat and other 
marine species are associated with elevated sound levels produced by 
airguns and other active acoustic sources. However, other potential 
impacts to the surrounding habitat from physical disturbance are also 
possible. This section describes the potential impacts to marine mammal 
habitat from the specified activity. Because the marine mammals in the 
area feed on fish and/or invertebrates there is also information on the 
species typically preyed upon by the marine mammals in the area.
    With regard to fish as a prey source for odontocetes and seals, 
fish are known to hear and react to sounds and to use sound to 
communicate (Tavolga et al., 1981) and possibly avoid predators (Wilson 
and Dill, 2002). Experiments have shown that fish can sense both the 
strength and direction of sound (Hawkins, 1981). Primary factors 
determining whether a fish can sense a sound signal, and potentially 
react to it, are the frequency of the signal and the strength of the 
signal in relation to the natural background noise level.
    Fishes produce sounds that are associated with behaviors that 
include territoriality, mate search, courtship, and aggression. It has 
also been speculated that sound production may provide the means for 
long distance communication and communication under poor underwater 
visibility conditions (Zelick et al., 1999), although the fact that 
fish communicate at low-frequency sound levels where the masking 
effects of ambient noise are naturally highest suggests that very long 
distance communication would rarely be possible. Fishes have evolved a 
diversity of sound generating organs and acoustic signals of various 
temporal and spectral contents. Fish sounds vary in structure, 
depending on the mechanism used to produce them (Hawkins, 1993). 
Generally, fish sounds are predominantly composed of low frequencies 
(less than 3 kHz).
    Since objects in the water scatter sound, fish are able to detect 
these objects through monitoring the ambient noise. Therefore, fish are 
probably able to detect prey, predators, conspecifics, and physical 
features by listening to environmental sounds (Hawkins, 1981). There 
are two sensory systems that enable fish to monitor the vibration-based 
information of their surroundings. The two sensory systems, the inner 
ear and the lateral line, constitute the acoustico-lateralis system.
    Although the hearing sensitivities of very few fish species have 
been studied to date, it is becoming obvious that the intra- and inter-
specific variability is considerable (Coombs, 1981). Nedwell et al. 
(2004) compiled and published available fish audiogram information. A 
noninvasive electrophysiological recording method known as auditory 
brainstem response is now commonly used in the production of fish 
audiograms (Yan, 2004). Generally, most fish have their best hearing in 
the low-frequency range (i.e., less than 1 kHz). Even though some fish 
are able to detect sounds in the ultrasonic frequency range, the 
thresholds at these higher frequencies tend to be considerably higher 
than those at the lower end of the auditory frequency range.
    Literature relating to the impacts of sound on marine fish species 
can be divided into the following categories: (1) Pathological effects; 
(2) physiological effects; and (3) behavioral effects. Pathological 
effects include lethal and sub-lethal physical damage to fish; 
physiological effects include primary and secondary stress responses; 
and behavioral effects include changes in exhibited behaviors of fish. 
Behavioral changes might be a direct reaction to a detected sound or a 
result of the anthropogenic sound masking natural sounds that the fish 
normally detect and to which they respond. The three types of effects 
are often interrelated in complex ways. For example, some physiological 
and behavioral effects could potentially lead to the ultimate 
pathological effect of mortality. Hastings and Popper (2005) reviewed 
what is known about the effects of sound on fishes and identified 
studies needed to address areas of uncertainty relative to measurement 
of sound and the responses of fishes. Popper et al. (2003/2004) also 
published a paper that reviews the effects of anthropogenic sound on 
the behavior and physiology of fishes.
    Potential effects of exposure to sound on marine fish include TTS, 
physical damage to the ear region, physiological stress responses, and 
behavioral responses such as startle response, alarm response, 
avoidance, and perhaps lack of response due to masking of acoustic 
cues. Most of these effects appear to be either temporary or 
intermittent and therefore probably do not significantly impact the 
fish at a population level. The studies that resulted in physical 
damage to the fish ears used noise exposure levels and durations that 
were far more extreme than would be encountered under conditions 
similar to those expected during Hilcorp's proposed survey.
    The level of sound at which a fish will react or alter its behavior 
is usually well above the detection level. Fish have been found to 
react to sounds when the sound level increased to about

[[Page 27910]]

20 dB above the detection level of 120 dB (Ona, 1988); however, the 
response threshold can depend on the time of year and the fish's 
physiological condition (Engas et al., 1993). In general, fish react 
more strongly to pulses of sound rather than a continuous signal 
(Blaxter et al., 1981), such as the type of sound that will be produced 
by the drillship, and a quicker alarm response is elicited when the 
sound signal intensity rises rapidly compared to sound rising more 
slowly to the same level.
    Investigations of fish behavior in relation to vessel noise (Olsen 
et al., 1983; Ona, 1988; Ona and Godo, 1990) have shown that fish react 
when the sound from the engines and propeller exceeds a certain level. 
Avoidance reactions have been observed in fish such as cod and herring 
when vessels approached close enough that received sound levels are 110 
dB to 130 dB (Nakken, 1992; Olsen, 1979; Ona and Godo, 1990; Ona and 
Toresen, 1988). However, other researchers have found that fish such as 
polar cod, herring, and capeline are often attracted to vessels 
(apparently by the noise) and swim toward the vessel (Rostad et al., 
2006). Typical sound source levels of vessel noise in the audible range 
for fish are 150 dB to 170 dB (Richardson et al., 1995a). In calm 
weather, ambient noise levels in audible parts of the spectrum lie 
between 60 dB to 100 dB.
    Short, sharp sounds can cause overt or subtle changes in fish 
behavior. Chapman and Hawkins (1969) tested the reactions of whiting 
(hake) in the field to an airgun. When the airgun was fired, the fish 
dove from 82 to 180 ft (25 to 55 m) depth and formed a compact layer. 
The whiting dove when received sound levels were higher than 178 dB re 
1 [micro]Pa (Pearson et al., 1992).
    Pearson et al. (1992) conducted a controlled experiment to 
determine effects of strong noise pulses on several species of rockfish 
off the California coast. They used an airgun with a source level of 
223 dB re 1 [micro]Pa. They noted:
     Startle responses at received levels of 200-205 dB re 1 
[micro]Pa and above for two sensitive species, but not for two other 
species exposed to levels up to 207 dB;
     Alarm responses at 177-180 dB for the two sensitive 
species, and at 186 to 199 dB for other species;
     An overall threshold for the above behavioral response at 
about 180 dB;
     An extrapolated threshold of about 161 dB for subtle 
changes in the behavior of rockfish; and
     A return to pre-exposure behaviors within the 20-60 minute 
exposure period.
    In summary, fish often react to sounds, especially strong and/or 
intermittent sounds of low frequency. Sound pulses at received levels 
of 160 dB re 1 [micro]Pa may cause subtle changes in behavior. Pulses 
at levels of 180 dB may cause noticeable changes in behavior (Chapman 
and Hawkins, 1969; Pearson et al., 1992; Skalski et al., 1992). It also 
appears that fish often habituate to repeated strong sounds rather 
rapidly, on time scales of minutes to an hour. However, the habituation 
does not endure, and resumption of the strong sound source may again 
elicit disturbance responses from the same fish.
    Some of the fish species found in the Arctic are prey sources for 
odontocetes and pinnipeds. A reaction by fish to sounds produced by 
Hilcorp's proposed survey would only be relevant to marine mammals if 
it caused concentrations of fish to vacate the area. Pressure changes 
of sufficient magnitude to cause that type of reaction would probably 
occur only very close to the sound source, if any would occur at all. 
Impacts on fish behavior are predicted to be inconsequential. Thus, 
feeding odontocetes and pinnipeds would not be adversely affected by 
this minimal loss or scattering, if any, of reduced prey abundance.
    Some mysticetes, including bowhead whales, feed on concentrations 
of zooplankton. Some feeding bowhead whales may occur in the Alaskan 
Beaufort Sea in July and August, but feeding bowheads are more likely 
to occur in the area after the cessation of survey operations. 
Reactions of zooplankton to sound are, for the most part, not known. 
Their ability to move significant distances is limited or nil, 
depending on the type of zooplankton. Behavior of zooplankters is not 
expected to be affected by the survey. These animals have exoskeletons 
and no air bladders. Many crustaceans can make sounds, and some 
crustacea and other invertebrates have some type of sound receptor. A 
reaction by zooplankton to sounds produced by the seismic survey would 
only be relevant to whales if it caused concentrations of zooplankton 
to scatter. Pressure changes of sufficient magnitude to cause that type 
of reaction would probably occur only very close to the sound source, 
if any would occur at all. Impacts on zooplankton behavior are 
predicted to be inconsequential. Thus, feeding mysticetes would not be 
adversely affected by this minimal loss or scattering, if any, of 
reduced zooplankton abundance.
    Based on the preceding discussion, the proposed activity is not 
expected to have any habitat-related effects that could cause 
significant or long-term consequences for individual marine mammals or 
their populations.

Proposed Mitigation

    In order to issue an incidental take authorization (ITA) under 
sections 101(a)(5)(A) and (D) of the MMPA, NMFS must, where applicable, 
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 (where relevant). This section summarizes the contents 
of Hilcorp's Marine Mammal Monitoring and Mitigation Plan (4MP). Later 
in this document in the ``Proposed Incidental Harassment 
Authorization'' section, NMFS lays out the proposed conditions for 
review, as they would appear in the final IHA (if issued).
    Hilcorp submitted a 4MP as part of its application (see ADDRESSES). 
Hilcorp's planned shallow geohazard survey incorporates both design 
features and operational procedures for minimizing potential impacts on 
marine mammals and on subsistence hunts. The 4MP is a combination of 
active monitoring in the area of operations and the implementation of 
mitigation measures designed to minimize project impacts to marine 
resources. Monitoring will provide information on marine mammals 
potentially affected by exploration activities, in addition to 
facilitating real time mitigation to prevent injury of marine mammals 
by industrial sounds or activities.

Vessel Related Mitigation Measures

    The general mitigation measures apply to all vessels that are part 
of the Foggy Island Bay sonar survey. The source vessel will operate 
under an additional set of specific mitigation measures during 
operations.
     To minimize collision risk with marine mammals, vessels 
shall not be operated at speeds that would make collisions likely. When 
weather conditions require, such as when visibility drops, vessels 
shall adjust speed accordingly to avoid the likelihood of marine mammal 
collisions.
     Vessel operators shall check the waters immediately 
adjacent to a vessel to ensure that no marine mammals will be injured 
when the vessel's propellers (or screws) are engaged.

[[Page 27911]]

     Vessel operators shall avoid concentrations or groups of 
whales and vessels shall not be operated in a way that separates 
members of a group. In proximity of feeding whales or aggregations, 
vessel speed shall be less than 10 knots.
     When within 900 ft. (300 m) of whales vessel operators 
shall take every effort and precaution to avoid harassment of these 
animals by:
    [cir] Reducing speed and steering around (groups of) whales if 
circumstances allow, but never cutting off a whale's travel path;
    [cir] Avoiding multiple changes in direction and speed.
     In general, the survey design will start in shallow water 
and work deeper to mitigate the potential ``herding'' effect.

Establishing Exclusion and Disturbance Zones

    Under current NMFS guidelines, the ``exclusion zone'' for marine 
mammal exposure to impulse sources is customarily defined as the area 
within which received sound levels are >=180 dB (rms) re 1 [mu]Pa for 
cetaceans and >=190 dB (rms) re 1 [mu]Pa for pinnipeds. These safety 
criteria are based on an assumption that SPL received at levels lower 
than these will not injure these animals or impair their hearing 
abilities, but at higher levels might have some such effects. 
Disturbance or behavioral effects to marine mammals from underwater 
sound may occur after exposure to sound at distances greater than the 
exclusion zones (Richardson et al. 1995). Currently, NMFS uses 160 dB 
(rms) re 1 [mu]Pa as the threshold for Level B behavioral harassment 
from impulse noise.
    The sounds generated by the multibeam echosounder and sidescan 
sonar are outside the hearing range of marine mammals. Sounds generated 
by the sub-bottom profiler are within the hearing range of all marine 
mammal species occurring in the area. The distance to 160 dB re 1 
[micro]Pa (rms) zone of influence (ZOI) is estimated at 30 m (Warner & 
McCrodan 2011). However, Hilcorp will establish a ZOI of 50 m around 
all sonar sources for more protective measures. The exclusion zones of 
all sonar equipment are less than 30 m from the sources.

Mitigation Measures for Sonar Equipment

(1) Ramp Up Procedure
    A ramp up of the sub-bottom profiler provides a gradual increase in 
sound levels, and involves a step-wise increase in the number and 
incremental levels of the sub-bottom profiler firing until the maximum 
level is achieved. The purpose of a ramp up (or ``soft start'') is to 
``warn'' cetaceans and pinnipeds in the vicinity of the survey and to 
provide time for them to leave the area and thus reducing startling 
responses from marine mammals.
(2) Shutdown Measures
    Although there is no exclusion zone expected from the sonar source 
operated by Hilcorp during its proposed shallow geohazard survey, 
Hilcorp proposes to implement shutdown measures when a marine mammals 
is sighted within the 50 m ZOI during the operation of the sub-bottom 
profiler.
    After showdown for more than 10 minutes, ramp-up shall not start 
until after the marine mammal is visually seen left the ZOI; or 15 
minutes have passed after the last detection of the marine mammal with 
shorter dive durations (pinnipeds and small odontocetes); or 30 minutes 
have passed after the last detection of the marine mammal with longer 
diver durations (mysticetes and large odontocetes, including beluga 
whales).
(3) Poor Visibility Conditions
    If during foggy conditions, heavy snow or rain, or darkness, the 
full 160 dB ZOI is not visible, sonar equipment cannot commence a ramp-
up procedure from a full shut-down. If the sub-bottom profiler has been 
operational before nightfall or before the onset of poor visibility 
conditions, it can remain operational throughout the night or poor 
visibility conditions.

Mitigation Conclusions

    NMFS has carefully evaluated Hilcorp's proposed mitigation measures 
and considered a range of other measures in the context of ensuring 
that NMFS prescribes the means of effecting the least practicable 
impact on the affected marine mammal species and stocks and their 
habitat. Our evaluation of potential measures included consideration of 
the following factors in relation to one another:
     The manner in which, and the degree to which, the 
successful implementation of the measures are expected to minimize 
adverse impacts to marine mammals;
     The proven or likely efficacy of the specific measure to 
minimize adverse impacts as planned; and
     The practicability of the measure for applicant 
implementation.
    Any mitigation measure(s) prescribed by NMFS should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below:
    1. Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    2. A reduction in the numbers of marine mammals (total number or 
number at biologically important time or location) exposed to received 
levels of sub-bottom profiler, or other activities expected to result 
in the take of marine mammals (this goal may contribute to 1, above, or 
to reducing harassment takes only).
    3. A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to received levels of sub-bottom profiler or other activities expected 
to result in the take of marine mammals (this goal may contribute to 1, 
above, or to reducing harassment takes only).
    4. A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to received 
levels of sub-bottom profiler or other activities expected to result in 
the take of marine mammals (this goal may contribute to 1, above, or to 
reducing the severity of harassment takes only).
    5. Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/disturbance 
of habitat during a biologically important time.
    6. For monitoring directly related to mitigation--an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.
    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has preliminarily 
determined that the proposed mitigation measures provide the means of 
effecting the least practicable impact on marine mammals species or 
stocks and their habitat, paying particular attention to rookeries, 
mating grounds, and areas of similar significance. Proposed measures to 
ensure availability of such species or stock for taking for certain 
subsistence uses are discussed later in this document (see ``Impact on 
Availability of Affected Species or Stock for Taking for Subsistence 
Uses'' section).

[[Page 27912]]

Proposed Monitoring and Reporting

    In order to issue an ITA for an activity, section 101(a)(5)(D) of 
the MMPA states that NMFS must set forth, ``requirements pertaining to 
the monitoring and reporting of such taking.'' The MMPA implementing 
regulations at 50 CFR 216.104 (a)(13) indicate that requests for ITAs 
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. 
Hilcorp submitted a marine mammal monitoring plan as part of the IHA 
application. The plan may be modified or supplemented based on comments 
or new information received from the public during the public comment 
period or from the peer review panel (see the ``Monitoring Plan Peer 
Review'' section later in this document).
    Monitoring measures prescribed by NMFS should accomplish one or 
more of the following general goals:
    1. An increase in our understanding of the likely occurrence of 
marine mammal species in the vicinity of the action, i.e., presence, 
abundance, distribution, and/or density of species.
    2. An increase in our understanding of the nature, scope, or 
context of the likely exposure of marine mammal species to any of the 
potential stressor(s) associated with the action (e.g. sound or visual 
stimuli), through better understanding of one or more of the following: 
the action itself and its environment (e.g. sound source 
characterization, propagation, and ambient noise levels); the affected 
species (e.g. life history or dive pattern); the likely co-occurrence 
of marine mammal species with the action (in whole or part) associated 
with specific adverse effects; and/or the likely biological or 
behavioral context of exposure to the stressor for the marine mammal 
(e.g. age class of exposed animals or known pupping, calving or feeding 
areas).
    3. An increase in our understanding of how individual marine 
mammals respond (behaviorally or physiologically) to the specific 
stressors associated with the action (in specific contexts, where 
possible, e.g., at what distance or received level).
    4. An increase in our understanding of how anticipated individual 
responses, to individual stressors or anticipated combinations of 
stressors, may impact either: the long-term fitness and survival of an 
individual; or the population, species, or stock (e.g. through effects 
on annual rates of recruitment or survival).
    5. An increase in our understanding of how the activity affects 
marine mammal habitat, such as through effects on prey sources or 
acoustic habitat (e.g., through characterization of longer-term 
contributions of multiple sound sources to rising ambient noise levels 
and assessment of the potential chronic effects on marine mammals).
    6. An increase in understanding of the impacts of the activity on 
marine mammals in combination with the impacts of other anthropogenic 
activities or natural factors occurring in the region.
    7. An increase in our understanding of the effectiveness of 
mitigation and monitoring measures.
    8. An increase in the probability of detecting marine mammals 
(through improved technology or methodology), both specifically within 
the safety zone (thus allowing for more effective implementation of the 
mitigation) and in general, to better achieve the above goals.

Proposed Monitoring Measures

    Monitoring will provide information on the numbers of marine 
mammals potentially affected by the exploration operations and 
facilitate real-time mitigation to prevent injury of marine mammals by 
industrial sounds or activities. These goals will be accomplished in 
the Beaufort Sea during 2015 by conducting vessel-based monitoring and 
passive acoustic monitoring to document marine mammal presence and 
distribution in the vicinity of the survey area.
    Visual monitoring by Protected Species Observers (PSOs) during 
shallow geohazard survey operations, and periods when these surveys are 
not occurring, will provide information on the numbers of marine 
mammals potentially affected by these activities and facilitate real-
time mitigation to prevent impacts to marine mammals by industrial 
sounds or operations. Vessel-based PSOs onboard the survey vessels will 
record the numbers and species of marine mammals observed in the area 
and any observable reaction of marine mammals to the survey activities 
in the Beaufort Sea.
(1) Vessel-Based Monitoring
(A) Protected Species Observers (PSOs)
    Vessel-based monitoring for marine mammals will be done by trained 
PSOs throughout the period of survey activities. The observers will 
monitor the occurrence of marine mammals near the survey vessel during 
all daylight periods during operation, and during most daylight periods 
when operations are not occurring. PSO duties will include watching for 
and identifying marine mammals; recording their numbers, distances, and 
reactions to the survey operations; and documenting ``take by 
harassment.''
    Two PSOs will be present on the main sonar vessel. The smaller 
skiff may only accommodate one at a time. Of these two PSOs, one will 
be on watch at all times, except during darkness.
    PSO teams will consist of Inupiat observers and experienced field 
biologists. Each vessel will have an experienced field crew leader to 
supervise the PSO team.
    Visual monitoring by the PSOs will be required to meet the 
following criteria:
     100% monitoring coverage during all periods of survey 
operations in daylight;
     Maximum of 4 consecutive hours on watch per PSO; and
     Maximum of 12 hours of watch time per day per PSO.
(B) PSO Qualifications and Training
    Lead PSOs will be individuals with experience as observers during 
recent seismic, site clearance and shallow hazards, and other 
monitoring projects in Alaska or other offshore areas in recent years. 
New or inexperienced PSOs will be paired with an experienced PSO or 
experienced field biologist so that the quality of marine mammal 
observations and data recording is kept consistent.
    Resumes for candidate PSOs will be provided to NMFS for review and 
acceptance of their qualifications. Inupiat observers will be 
experienced in the region and familiar with the marine mammals of the 
area. All observers will complete a training course designed to 
familiarize individuals with monitoring and data collection procedures.
(C) Marine Mammal Observer Protocol
    The PSOs will watch for marine mammals during all periods of source 
operations and for a minimum of 30 minutes prior to the planned start 
of sonar operations after an extended shutdown. Marine mammal 
monitoring shall continue throughout sonar operations and last for 30 
minutes after the finish of sonar operations during daylight hours. 
Hilcorp vessel crew and operations personnel will also watch for marine 
mammals, as practical, to assist and alert the PSOs for the sub-bottom 
profiler to be shut down if marine mammals are observed in or about to 
enter the 50-m ZOI.
    PSOs will also perform vessel-based marine mammal monitoring during

[[Page 27913]]

vessel transit when the shallow geohazard survey is not being 
conducted. Marine mammal sighting data collected during the non-survey 
period will be compared with those during the survey to analyze the 
effects of the activities.
    The PSOs will watch for marine mammals from the best available 
vantage point on the vessels. The PSOs will scan the area around the 
vessel systematically with reticle binoculars (e.g., 7 x 50 and 16-40 x 
80) and with the naked eye. GPS unit and laptop computer(s) will also 
be available for PSOs onboard survey vessels.
    The observers will give particular attention to the areas within 
the marine mammal exclusion zones around the source vessels.
    When a marine mammal is seen approaching or within the 50-m ZOI, 
the survey crew will be notified immediately so that mitigation 
measures called for in the applicable authorization(s) can be 
implemented.
    Information to be recorded by PSOs will include:
     Species, group size, age/size/sex categories (if 
determinable), physical description of features that were observed or 
determined not to be present in the case of unknown or unidentified 
animals;
     Behavior when first sighted and after initial sighting;
     Heading (if consistent), bearing and distance from 
observer;
     Apparent reaction to activities (e.g., none, avoidance, 
approach, paralleling, etc.), closest point of approach, and behavioral 
pace;
     Time, location, speed, and activity of the vessel, sea 
state, ice cover, visibility, and sun glare; and
     Positions of other vessel(s) (if present) in the vicinity 
of the observer location.
    The vessel's position, speed, water depth, sea state, ice cover, 
visibility, and sun glare will also be recorded at the start and end of 
each observation watch, every 30 minutes during a watch, and whenever 
there is a change in any of those variables.
(2) Acoustic Monitoring
    Passive acoustic monitoring (PAM) will be conducted to document 
ambient noise conditions, to examine the spatial and temporal 
distribution of marine mammals based on acoustic detections of their 
vocalizations, and to characterize the long-range propagation of sounds 
produced during the geohazard survey. The goal of the program is to 
address knowledge gaps about ambient sound levels and the distributions 
and migration paths of several marine mammal species including bowhead 
whales, beluga whales, and seals.
    The acoustic data will be collected with Autonomous Multichannel 
Acoustic Recorder (AMAR) systems deployed on the seabed for an extended 
period. Two AMARs with different sampling rates will be deployed on the 
seabed for 3 months. An AMAR with a sampling rate of 64 kHz (24 bits) 
will be deployed at 500 m from the offshore end of the survey line and 
will record continuously. A high-frequency AMAR with a sampling rate of 
380 kHz (16 bits) will be deployed at 5,000 m from the offshore end of 
the survey line. This high-frequency AMAR will be operated at 380 kHz 
(16 bits) for 2 minutes each hour and the rest of the time at 64 kHz 
(24 bits). The AMARs will be calibrated using pistonphone calibrators 
immediately before and after each deployment. These calibrations are 
accurate to less than 0.5 dB absolute.

Monitoring Plan Peer Review

    The MMPA requires that monitoring plans be independently peer 
reviewed ``where the proposed activity may affect the availability of a 
species or stock for taking for subsistence uses'' (16 U.S.C. 
1371(a)(5)(D)(ii)(III)). Regarding this requirement, NMFS' implementing 
regulations state, ``Upon receipt of a complete monitoring plan, and at 
its discretion, [NMFS] will either submit the plan to members of a peer 
review panel for review or within 60 days of receipt of the proposed 
monitoring plan, schedule a workshop to review the plan'' (50 CFR 
216.108(d)).
    NMFS has established an independent peer review panel to review 
Hilcorp's 4MP for the proposed shallow geohazard survey in the Beaufort 
Sea. The panel has met in early March 2015, and provided comments and 
recommendations to NMFS in April 2015. The full panel report can be 
viewed on the Internet at: https://www.nmfs.noaa.gov/pr/permits/incidental.htm.
    NMFS provided the panel with Hilcorp's IHA application and 
monitoring plan and asked the panel to answer the following questions:
    1. Will the applicant's stated objectives effectively further the 
understanding of the impacts of their activities on marine mammals and 
otherwise accomplish the goals stated above? If not, how should the 
objectives be modified to better accomplish the goals above?
    2. Can the applicant achieve the stated objectives based on the 
methods described in the plan?
    3. Are there technical modifications to the proposed monitoring 
techniques and methodologies proposed by the applicant that should be 
considered to better accomplish their stated objectives?
    4. Are there techniques not proposed by the applicant (i.e., 
additional monitoring techniques or methodologies) that should be 
considered for inclusion in the applicant's monitoring program to 
better accomplish their stated objectives?
    5. What is the best way for an applicant to present their data and 
results (formatting, metrics, graphics, etc.) in the required reports 
that are to be submitted to NMFS (i.e., 90-day report and comprehensive 
report)?
    The peer-review panel report contains recommendations that the 
panel members felt were applicable to the Hilcorp' monitoring plans. 
The panel believes that the objectives for both vessel-based and 
passive acoustic monitoring are appropriate, and agrees that the 
objective of real-time mitigation of potential disturbance of marine 
mammals would be met through visual monitoring. Nevertheless, the panel 
is concerned that there may also be behavioral effects resulting from 
the use of single and multi-beam echosounders and side-scan sonar that 
may warrant real-time mitigation to avoid disturbance, and provide a 
series of recommendations to improve efficiencies and effectiveness of 
monitoring and mitigation measures.
    Specific recommendations provided by the peer review panel to 
enhance marine mammal monitoring and reporting measures are:
    (1) Deploying an additional observer on the source vessel such that 
at least two observers are on watch during all daylight hours;
    (2) Monitoring for marine mammals also be conducted during non-
survey activities to assist in the collection of baseline information 
from which to analyze the effects of the activities;
    (3) Deploying a third autonomous multichannel acoustic recorder 
(AMAR) and arrange the AMARs in a triangular array, as depicted in 
Figure 1 of the panel report, with the 500 m AMAR be a high-frequency 
AMAR, for marine mammal monitoring;
    (4) Using AMAR to collect data on cumulative sound exposure level 
over 24 hours (cSEL24), in particular during the use of the 
two sub-bottom profilers;
    (5) Ground-truthing data collected by AMARs in consultation with 
biologists experienced in Arctic species vocalizations and to include 
error rates for automatic detection to ensure the

[[Page 27914]]

accurate classification of vocalizations by species;
    (6) Collaborating with other entities collecting data on marine 
mammal vocalizations in the Beaufort Sea to improve auto-detection and 
manual capabilities for identifying species in which acoustic data are 
limited or lacking (e.g., spotted seals); and
    (7) Including information from high frequency acoustic recordings 
in reports to provide a better understanding of source levels and other 
acoustic characteristics of the active acoustics survey equipment, such 
as spectral content, and received levels in root-mean-squared (RMS) dB, 
sound exposure level (SEL), dB peak to peak and \1/3\ octave bands.
    In addition, although not requested by NMFS under the MMPA, the 
panel also provided several mitigation measures. These recommendations 
are:
    (1) Hilcorp limit operations at night or during periods of low 
visibility so that marine mammals do not enter the safety zone 
undetected;
    (2) Hilcorp specify that the delay for ramp-up and after a shut-
down should be 15 minutes for species with short dive durations (small 
odontocetes and pinnipeds) and 30 minutes for species with longer diver 
durations (mysticetes and large odontocetes, including beluga whales);
    (3) Additional sound source information from the various active 
acoustic equipment proposed for the survey be obtained by maneuvering 
the source vessels over the high frequency AMARs; and
    (4) Hilcorp conduct the survey starting closest to shore and 
proceeding offshore to avoid any potential ``herding'' effect of marine 
mammals into shallow waters, as was implicated in a mass stranding of 
melon headed whales off Madagascar during a multi-beam echosounder 
survey (Southall et al. 2013).
    NMFS discussed these recommendations with Hilcorp to improve its 
monitoring and reporting measures, and to some extent, as well as 
mitigation measures. As a result, Hilcorp agrees to implement the 
following recommendations:
    (1) Hilcorp will perform vessel-based marine mammal monitoring by 
protected species observers (PSOs) during vessel transit when the 
shallow geohazard survey is not being conducted. Marine mammal sighting 
data collected during the non-survey period will be compared with those 
during the survey to analyze the effects of the activities.
    (2) Hilcorp and its contractor JASCO will deploy a high-frequency 
AMAR at the 5000 m site for detecting beluga clicks. The high-frequency 
AMAR would be operated at 380 kHz (16 bits) for about 2 minutes each 
hour and the rest of the time at 64 kHz (24 bits) for the 3 months 
deployment. The reason for deploying the high-frequency AMAR at 5000 m 
location, which NMFS concurs, is that there is a higher likelihood of 
detecting marine mammal acoustics in the deeper water farther from the 
island.
    (3) Hilcorp will work with JASCO to use AMAR to collect data on 
cumulative sound exposure level over 24 hours (cSEL24), in 
particular during the use of the two sub-bottom profilers.
    (4) Hilcorp will work with JASCO to ground-truth data collected by 
AMARs in consultation with biologists experienced in Arctic species 
vocalizations and to include error rates for automatic detection to 
ensure the accurate classification of vocalizations by species.
    (5) Hilcorp is open to sharing data and work with its contractor 
JASCO to collaborate with other researchers. In addition, Hilcorp and 
JASCO will make the passive acoustic recording data, including data on 
marine mammal vocalizations, publically available for researchers. 
These data sharing/collaboration efforts will enable scientists to 
purse a variety of studies concerning the acoustic environment, marine 
mammal bioacoustics, and potential activity effects on marine mammals 
in the survey area.
    (6) Hilcorp will including information from high frequency acoustic 
recordings in reports to provide a better understanding of source 
levels and other acoustic characteristics of the active acoustics 
survey equipment, such as spectral content, and received levels in 
root-mean-squared (RMS) dB, sound exposure level (SEL), dB peak to peak 
and \1/3\ octave bands.
    Furthermore, Hilcorp agrees to implement the following mitigation 
recommendation and provided additional information in regard to the 
peer-review panel report:
    (1) Hilcorp will specify that the delay for ramp-up and after a 
shut-down should be 15 minutes for species with short dive durations 
(small odontocetes and pinnipeds) and 30 minutes for species with 
longer diver durations (mysticetes and large odontocetes, including 
beluga whales).
    (2) Regarding sound source information from the various active 
acoustic equipment proposed for Hilcorp's shallow geohazard survey, 
acoustic characteristics of these equipment or its equivalents were 
previously measured by JASCO. The measurement results in the following 
reports that are posted on NMFS Web site:
     Statoil 2011 Shallow Hazards Survey 90-day Report (Chapter 
3) (https://www.nmfs.noaa.gov/pr/pdfs/permits/statoil_90day_report2011.pdf).
     Shell 2013 Shallow Hazards Survey 90-day Report (Chapter 
2) (https://www.nmfs.noaa.gov/pr/permits/incidental/oilgas/2013_shell_monitoringreport.pdf).
    (3) Regarding the panel's recommendation on Hilcorp's survey 
transect design, Hilcorp states that it can start in shallow water and 
work deeper to mitigate the potential ``herding'' effect. Hilcorp's 
plan is to divide the corridor into multiple sub-sections based on 
depth and work each section independently. This method is necessary for 
side scan sonar operations as each subsection will have a different 
range setting and line spacing that is related to depth.
    All these aforementioned recommendations from the peer-review panel 
are included in the proposed mitigation and monitoring measures for 
Hilcorp's 2015 open-water shallow geohazard survey in the Beaufort Sea.
    However, Hilcorp will not able to increase the number of vessel-
based PSOs onboard the survey vessel. The number of PSOs onboard the 
vessel is limited by the available berth space. The survey vessels used 
for the proposed shallow geohazard survey can only accommodate maximum 
of 2 PSOs. Nevertheless, NMFS considers that due to the exceptionally 
small ensonified zones (no exclusion zone, with the radius of ZOI at 30 
m from the source), one PSO on watch onboard the survey vessel is 
adequate.
    In regard to an additional AMAR to be deployed in the vicinity of 
the survey area, NMFS worked with Hilcorp and determined that 
deployment of three AMARs would be cost prohibitive to Hilcorp, given 
the small project budget of the shallow geohazard survey. In addition, 
due to the short duration and minimal impact of the proposed shallow 
geohazard survey, the currently passive acoustic monitoring, improved 
with a high-frequency AMAR, is adequate to provide needed information 
to assess potential environmental effects from the proposed project.
    Finally, NMFS does not agree with one of the panel's 
recommendations that Hilcorp limit operations at night or during 
periods of low visibility so that marine mammals do not enter the 
safety zone undetected. As mentioned previously, there is not no safety 
zone (exclusion zone) because of the low intensity high-frequency sonar

[[Page 27915]]

equipment being employed in the proposed shallow geohazard survey. In 
addition, limiting survey at night or during periods of low visibility 
would increase the survey duration, thus extend the noise output from 
survey vessels in the area. NMFS believes that as long as the 50-m ZOI 
is cleared of marine mammals before the ramp-up of sonar equipment 
during daylight hours with good visibility, shallow hazard survey can 
be carried out with minimum adverse effects to marine mammals.

Reporting Measures

(1) Technical Report
    The results of Hilcorp's 2015 vessel-based monitoring, including 
estimates of ``take'' by harassment, will be presented in a ``90-day'' 
draft Technical Report, to be submitted to NMFS within 90 days after 
the end of the shallow geohazard survey, and then in a final Technical 
Report, which will address any comments NMFS had on the draft. The 
Technical Report will include:
    (a) Summaries of monitoring effort (e.g., total hours, total 
distances, and marine mammal distribution through the study period, 
accounting for sea state and other factors affecting visibility and 
detectability of marine mammals);
    (b) Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare);
    (c) Species composition, occurrence, and distribution of marine 
mammal sightings, including date, water depth, numbers, age/size/gender 
categories (if determinable), group sizes, and ice cover;
    (d) Data analysis separated into periods when a sonar source is 
operating and when it is not, to better assess impacts to marine 
mammals--the final and comprehensive report to NMFS should summarize 
and plot:
     Data for periods when a sonar source is active and when it 
is not; and
     The respective predicted received sound conditions over 
fairly large areas (tens of km) around operations;
    (e) Sighting rates of marine mammals during periods with and 
without sonar activities (and other variables that could affect 
detectability), such as:
     Initial sighting distances versus sonar activity state;
     Closest point of approach versus sonar activity state;
     Observed behaviors and types of movements versus sonar 
activity state;
     Numbers of sightings/individuals seen versus sonar 
activity state;
     Distribution around the survey vessel versus sonar 
activity state; and
     Estimates of take by harassment;
    (f) Results from all hypothesis tests, including estimates of the 
associated statistical power, when practicable;
    (g) Estimates of uncertainty in all take estimates, with 
uncertainty expressed by the presentation of confidence limits, a 
minimum-maximum, posterior probability distribution, or another 
applicable method, with the exact approach to be selected based on the 
sampling method and data available; and
    (h) A clear comparison of authorized takes and the level of actual 
estimated takes.
    In addition, the technical report will include analysis on acoustic 
monitoring such as:
    (a) Cumulative sound exposure level over 24 hours 
(cSEL24), in particular during the use of the two sub-bottom 
profilers;
    (b) Ground-truth of data collected by AMARs in consultation with 
biologists experienced in Arctic species vocalizations with error rates 
for automatic detection to ensure the accurate classification of 
vocalizations by species; and
    (c) Information of source levels and other acoustic characteristics 
of the active acoustics survey equipment, such as spectral content, and 
received levels in root-mean-squared (RMS) dB, sound exposure level 
(SEL), dB peak to peak and \1/3\ octave bands.
    Finally, Hilcorp will share data and work with its contractor JASCO 
to collaborate with other researchers. The passive acoustic recording 
data, including data on marine mammal vocalizations, will be made 
publically available for researchers. These data sharing/collaboration 
efforts will enable scientists to purse a variety of studies concerning 
the acoustic environment, marine mammal bioacoustics, and potential 
activity effects on marine mammals in the survey area.
(5) Notification of Injured or Dead Marine Mammals
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA, 
such as a serious injury, or mortality (e.g., ship-strike, gear 
interaction, and/or entanglement), Hilcorp would immediately cease the 
specified activities and immediately report the incident to the Chief 
of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, and the Alaska Regional Stranding Coordinators. 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 prohibited take. NMFS would work with Hilcorp to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Hilcorp would not be able 
to resume its activities until notified by NMFS via letter, email, or 
telephone.
    In the event that Hilcorp discovers a dead marine mammal, and the 
lead PSO determines that the cause of the death is unknown and the 
death is relatively recent (i.e., in less than a moderate state of 
decomposition as described in the next paragraph), Hilcorp would 
immediately report the incident to the Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, and the 
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators. 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 Hilcorp to determine whether modifications in the activities are 
appropriate.
    In the event that Hilcorp discovers a dead marine mammal, and the 
lead PSO determines that the 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), 
Hilcorp would report the incident to the Chief of the Permits and 
Conservation Division, Office of Protected Resources, NMFS, and the 
NMFS Alaska Stranding Hotline and/or by email to the Alaska Regional 
Stranding Coordinators, within 24 hours of the discovery. Hilcorp would 
provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network. Hilcorp

[[Page 27916]]

can continue its operations under such a case.

Estimated Take by Incidental Harassment

    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild [Level A harassment]; or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering [Level B harassment]. Only take by Level B behavioral 
harassment is anticipated as a result of the proposed shallow geohazard 
survey. Noise propagation from subbottom profilers is expected to 
harass, through behavioral disturbance, affected marine mammal species 
or stocks.
    The full suite of potential impacts to marine mammals from various 
industrial activities was described in detail in the ``Potential 
Effects of the Specified Activity on Marine Mammals'' section found 
earlier in this document. The potential effects of sound from the 
proposed shallow geohazard survey without any mitigation might include 
one or more of the following: Tolerance; masking of natural sounds; 
behavioral disturbance; non-auditory physical effects; and, at least in 
theory, temporary or permanent hearing impairment (Richardson et al., 
1995a). As discussed in the following sections in this document, NMFS 
estimates that Hilcorp's activities will most likely result in 
behavioral disturbance, including avoidance of the ensonified area or 
changes in speed, direction, and/or diving profile of one or more 
marine mammals. For reasons discussed previously in this document, 
hearing impairment (TTS and PTS) is highly unlikely to occur based on 
the fact that most of the equipment to be used during Hilcorp's 
proposed shallow geohazard survey does not have source levels high 
enough to elicit even mild TTS and/or the fact that certain species are 
expected to avoid the ensonified areas close to the operations. 
Additionally, non-auditory physiological effects are anticipated to be 
minor, if any would occur at all.
    For impulsive sounds, such as the signals produced by the subbottom 
profiler sources during the shallow geohazard survey, NMFS uses a 
received level of 160-dB (rms) to indicate the onset of Level B 
harassment. Hilcorp provided calculations of the 160-dB isopleth 
produced by the subbottom profiler and then used that isopleth to 
estimate takes by harassment. Hilcorp provides a full description of 
the methodology used to estimate takes by harassment in its IHA 
application (see ADDRESSES), which is also provided in the following 
sections.
    Hilcorp has requested authorization to take bowhead, gray, 
humpback, minke, killer, and beluga whales, harbor porpoise, and 
ringed, spotted, bearded, and ribbon seals incidental to shallow 
geohazard survey in the Beaufort Sea. However, as stated previously in 
this document, humpback, minke, and killer whales, harbor porpoise, and 
ribbon seal are considered extralimital in the proposed shallow 
geohazard survey area. Therefore, NMFS is not proposing to authorize 
take of these species.

Basis for Estimating ``Take by Harassment''

    ``Take by Harassment'' is described in this section and was 
calculated in Hilcorp's application by multiplying the expected 
densities of marine mammals that may occur near the shallow geohazard 
survey areas where received noise levels are higher than 160 dB re 1 
[mu]Pa (rms) created by the subbottom profiler during the survey.

Marine Mammal Density Estimates

    Whale species are migratory and therefore show a seasonal 
distribution, with different densities for the summer period (covering 
July and August) and the fall period (covering September and October). 
Seal species in the Beaufort Sea do not show a distinct seasonal 
distribution during the open water period between July and October. 
Data acquisition of the proposed sonar survey will only take place in 
summer (before start of Nuiqsut whaling), therefore only estimates of 
marine mammal densities for the summer are included in the take 
calculation. Whale and seal densities in the Beaufort Sea will further 
depend on the presence of sea ice. However, if ice cover within or 
close to the sonar survey area is more than approximately 10%, sonar 
survey activities may not start or be halted for safety reasons. 
Densities related to ice conditions are therefore not included in the 
take estimates.
    Spatial differentiation is another important factor for marine 
mammal densities, both in latitudinal and longitudinal gradient. Taking 
into account the shallow water operations of the proposed sonar survey 
area and the associated area of influence, data from the nearshore zone 
of the Beaufort Sea is used for the calculation of densities, if 
available.
    Density estimates are based on best available data. Because 
available data did not always cover the area of interest, estimates are 
subject to large temporal and spatial variation. Though correction 
factors for perception and availability bias have been calculated for 
certain coastal areas they were not always known for this study area. 
There is some uncertainty in the 2014 raw data and assumptions were 
used in the estimated number of exposures. To provide allowance for 
these uncertainties, maximum density estimates have been provided in 
addition to average density estimates.
    A summary of marine mammal density in the proposed Hilcorp survey 
area is provided in Table 3.

   Table 3--Estimated Summer Densities of Whales and Sighting Rates of
 Seals (Average and Maximum) for the Proposed North Prudhoe Bay Survey.
  Densities Are Provided in Number of Individuals per km2 (IND/km\2\),
      Sighting Rates in Number of Individuals per Hour (INDV/hr.).
------------------------------------------------------------------------
              Species                    Average            Maximum
------------------------------------------------------------------------
                                              Summer Densities
                                                (INDV/km\2\)
                                   -------------------------------------
Bowhead whale.....................             0.0088             0.0200
Beluga............................             0.0008             0.0078
                                   -------------------------------------
                                            Summer Sighting Rates
                                                 (INDV/hr.)
                                   -------------------------------------
Ringed seal.......................              0.122              0.397
Bearded seal......................              0.033              0.107

[[Page 27917]]

 
Spotted seal......................              0.039              0.126
------------------------------------------------------------------------

Level B Harassment Zone Distance

    As discussed earlier in this document, the operating frequencies of 
the multibeam, single-beam, and sidescan sonar equipment in Hilcorp's 
proposed shallow geohazard survey are above the hearing range of all 
marine mammals and therefore are not expected to have take of marine 
mammals. Estimated distance to sound pressure levels of 160 dB re 1 
[mu]Pa, generated by the proposed sub-bottom equipment is 30 m from the 
source. However, as stated in this document earlier, Hilcorp proposes 
to implement a 50 m shutdown zone for the Level B behavioral 
harassment. Therefore, the calculation of marine mammal take is based 
on the number of animals exposed within the 50 m radius.

Potential Number of ``Takes by Harassment''

    This section provides estimates of the number of individuals 
potentially exposed to pulsed sound levels >=160 dB re 1 [mu]Pa rms by 
shallow geohazard survey using a subbottom profiler. The estimates are 
based on a consideration of the number of marine mammals that might be 
affected by operations in the Beaufort Sea during 2015 and the 
anticipated area exposed to those sound levels.
    The potential number of bowhead whales and belugas that might be 
exposed to the 160 dB re 1 [mu]Pa (rms) sound pressure level was 
calculated by multiplying:
     The expected bowhead and beluga density as provided in 
Table 3;
     The total 160 dB re 1 [mu]Pa (rms) ensonified area in a 
single hour by the vessel travelling at 3 knots; and
     The estimated number of hours that the source vessels are 
operating.
    The calculated area (0.0079 km\2\) expected to be ensonified is 
determined based on the maximum distance to the 160 dB re 1 [mu]Pa 
(rms) sound pressure level for the Sub-bottom profiler, which is 0.05 
km.
    The estimated number of 24-hr days of sonar operations was 
determined by assuming a 25% downtime during the planned 45-day time 
span of the sonar survey period. Downtime is related to weather, 
equipment maintenance, mitigation implementation, and other 
circumstances. The total number of full 24-hr days that data 
acquisition is expected to occur is ~34 days or 816 hours.
    The total 160 dB re 1 [mu]Pa (rms) ensonified area in a single hour 
by the vessel is calculated as 0.556 km\2\/hr.
    The average and maximum number of bowhead whales potentially 
exposed to sonar sound levels of 160 dB re 1[mu]Pa (rms) or more is 
estimated at 4 and 9 respectively. The limited number of exposures is 
due to the low estimated density of bowheads in Foggy Island Bay during 
July and August, the short duration of the survey, and the small 
acoustic footprint. For the requested authorization, the maximum number 
was increased by three to account for unexpected bowhead occurrences.
    The average and maximum number of potential beluga exposures to 160 
dB is <1. Belugas are known to show aggregate behavior and can occur in 
large numbers in nearshore zones, as evidenced by the sighting from 
Endicott in August 2013. Although beluga whales are not expected to 
frequent the vicinity of the Liberty Unit shallow geohazard survey 
area, their occurrence is still a possibility. To account for the 
potential average take of 1 beluga whale per day during the 45-day 
survey period, NMFS proposes a take authorization of 45 beluga whales 
for Hilcorp's shallow geohazard survey. Chance encounters with small 
numbers of other whale species are possible, but exposures to 160 dB or 
more are very unlikely for these species.
    Although gray whale density is not known, this species has been 
occasionally sited in the Arctic, and Hilcorp is requesting takes of 3 
individuals of gray whales by Level B behavioral harassment (Table 4).
    The estimated number of seals that might be exposed to pulsed 
sounds of 160 dB re 1 [mu]Pa (rms) is calculated by multiplying:
     The expected species specific sighting rate as provided in 
Table 3; and
     The total number of hours that each source vessel will be 
operating during the data acquisition period.
    The estimated number of hours that the sonar equipment will operate 
was determined by assuming a 25% downtime during a 45-day survey 
period, which is a total of 816 hours (34 days of 24 hour operations).
    These estimated exposures do not take into account the mitigation 
measures that will be implemented, such as marine mammal observers 
watching for animals, shutdowns or power downs of the equipment when 
marine mammals are seen within defined ranges. These measures will 
further reduce the number of exposures and expected short-term 
reactions, and minimize any effects on hearing sensitivity.
    A summary of the request takes and percent take among the 
population is provided in Table 4.

   Table 4--The Total Number of Potential Exposures of Marine Mammals to Sound Levels >=160 dB re 1 [mu]Pa rms
  During the Hilcorp's Proposed Shallow Geohazard Survey in the Beaufort Sea, Alaska, 2015. Estimates Are Also
                                      Shown as a Percent of Each Population
----------------------------------------------------------------------------------------------------------------
                                                                                      Number
                             Species                                 Abundance       potential      % Estimated
                                                                                     exposure       population
----------------------------------------------------------------------------------------------------------------
Beluga whale (Beaufort Sea stock)...............................          39,258              45            0.11
Bowhead whale...................................................          19,534              12            0.06
Gray whale......................................................          19,126               3            0.02
Bearded seal....................................................         155,000             100            0.06
Ringed seal.....................................................         300,000             350            0.17

[[Page 27918]]

 
Spotted seal....................................................         141,479             120            0.08
----------------------------------------------------------------------------------------------------------------

Analysis and Preliminary Determinations

Negligible Impact

    Negligible impact is ``an impact resulting from the specified 
activity that cannot be reasonably expected to, and is not reasonably 
likely to, adversely affect the species or stock through effects on 
annual rates of recruitment or survival'' (50 CFR 216.103). A 
negligible impact finding is based on the lack of likely adverse 
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of Level B harassment takes, 
alone, is not enough information on which to base an impact 
determination. In addition to considering estimates of the number of 
marine mammals that might be ``taken'' through behavioral harassment, 
NMFS must consider other factors, such as the likely nature of any 
responses (their intensity, duration, etc.), the context of any 
responses (critical reproductive time or location, migration, etc.), as 
well as the number and nature of estimated Level A harassment takes, 
the number of estimated mortalities, effects on habitat, and the status 
of the species.
    No injuries or mortalities are anticipated to occur as a result of 
Hilcorp's proposed shallow geohazard survey, and none are proposed to 
be authorized. Additionally, animals in the area are not expected to 
incur hearing impairment (i.e., TTS or PTS) or non-auditory 
physiological effects. The takes that are anticipated and authorized 
are expected to be limited to short-term Level B behavioral harassment. 
While the sonar sources are expected to be operated for approximately 
45 days, the project timeframe will occur when cetacean species are 
typically not found in the project area or are found only in low 
numbers. While pinnipeds are likely to be found in the proposed project 
area more frequently, their distribution is dispersed enough that they 
likely will not be in the Level B harassment zone continuously. As 
mentioned previously in this document, pinnipeds appear to be more 
tolerant of anthropogenic sound than mysticetes.
    Most of the marine mammals encountered will likely show overt 
disturbance (avoidance) only if they receive sonar sounds with levels 
>= 160 dB re 1 [mu]Pa. However, the estimated 160 dB zone is only 30 m 
from the source, which means that the animals have to be very close to 
the source vessel to be exposure to noise levels that could cause Level 
B harassment. In addition, Hilcorp will implement shutdown measures if 
a marine mammal is sighted within or is moving towards the 160 dB 
isopleths.
    Taking into account the mitigation measures that are planned, 
effects on marine mammals are generally expected to be restricted to 
avoidance of a limited area around Hilcorp's proposed open-water 
activities and short-term changes in behavior, falling within the MMPA 
definition of ``Level B harassment.'' Mitigation measures, such as 
controlled vessel speed, dedicated marine mammal observers, non-
pursuit, ramp up procedures, and shut downs or power downs when marine 
mammals are seen within or approaching the ZOI, will further reduce 
short-term reactions. In all cases, the effects are expected to be 
short-term, with no lasting biological consequence.
    Of the six marine mammal species likely to occur in the proposed 
marine survey area, bowhead whale and ringed seal are listed as 
endangered and threatened under the ESA, respectively. These species 
are also designated as ``depleted'' under the MMPA. Despite these 
designations, the Bering-Chukchi-Beaufort stock of bowheads has been 
increasing at a rate of 3.4 percent annually for nearly a decade (Allen 
and Angliss 2010). Additionally, during the 2001 census, 121 calves 
were counted, which was the highest yet recorded. The calf count 
provides corroborating evidence for a healthy and increasing population 
(Allen and Angliss 2010). There is no critical habitat designated in 
the U.S. Arctic for the bowhead whales. The Arctic stock of ringed 
seals have been listed by NMFS as threatened under the ESA. None of the 
other species that may occur in the project area are listed as 
threatened or endangered under the ESA or designated as depleted under 
the MMPA.
    Potential impacts to marine mammal habitat were discussed 
previously in this document (see the ``Anticipated Effects on Habitat'' 
section). Although some disturbance of food sources of marine mammals 
is possible, any impacts are anticipated to be minor enough as to not 
affect rates of recruitment or survival of marine mammals in the area. 
The marine survey activities would occur in a localized area, and given 
the vast area of the Arctic Ocean where feeding by marine mammals 
occurs, any missed feeding opportunities in the direct project area 
could be offset by feeding opportunities in other available feeding 
areas.
    In addition, no important feeding or reproductive areas are known 
in the vicinity of Hilcorp's proposed shallow geohazard survey. No 
critical habitat of ESA-listed marine mammal species occurs in the 
Beaufort Sea.
    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 Hilcorp's proposed shallow geohazard survey in the 
Beaufort Sea, Alaska, will have a negligible impact on the affected 
marine mammal species or stocks.

Small Numbers

    The requested takes proposed to be authorized represent less than 
0.2% of all populations or stocks potentially impacted (see Table 4 in 
this document). These take estimates represent the percentage of each 
species or stock that could be taken by Level B behavioral harassment 
if each animal is taken only once. The numbers of marine mammals 
estimated to be taken are small proportions of the total populations of 
the affected species or stocks. In addition, the mitigation and 
monitoring measures (described previously in this document) proposed 
for inclusion in the IHA (if issued) are expected to reduce even 
further any potential disturbance to marine mammals.

[[Page 27919]]

    Based on the analysis contained herein of the likely effects of the 
specified activity on marine mammals and their habitat, and taking into 
consideration the implementation of the mitigation and monitoring 
measures, NMFS preliminarily finds that small numbers of marine mammals 
will be taken relative to the populations of the affected species or 
stocks.

Impact on Availability of Affected Species or Stock for Taking for 
Subsistence Uses

Relevant Subsistence Uses

    Marine mammals are legally hunted in Alaskan waters by coastal 
Alaska Natives and represent between 60% and 80% of their total 
subsistence harvest. The species regularly harvested by subsistence 
hunters in and around the Beaufort Sea are bowhead and beluga whales, 
and ringed, spotted, and bearded seals. The importance of each of the 
subsistence species varies among the communities and is mainly based on 
availability and season.
    The communities closest to the project area are, from west to east, 
the villages of Barrow, Nuiqsut and Kaktovik. Barrow is located >200 mi 
west from the Hilcorp's proposed survey area. It is the largest 
community on the Alaska's Beaufort Sea coast. Important marine 
subsistence resources for Barrow include bowhead and beluga whales, and 
ice seals. Nuiqsut is located near the mouth of the Colville River, 
about 55 mi southwest of the proposed project area. Most important 
marine subsistence resource for Nuiqsut is the bowhead whale, and to a 
lesser extent belugas and seals. Nuiqsut hunters use Cross Island, (~20 
mi northwest of the project area) as a base to hunt for bowhead whales 
during the fall migration and have historically hunted bowhead whales 
as far east as Flaxman Island. Kaktovik is located on Barter Island, 
about 120 mi east of the project area. Major marine subsistence 
resources include bowhead and beluga whales, and seals.
(1) Bowhead Whale
    The bowhead whale is a critical subsistence and cultural resource 
for the North Slope communities of Barrow, Nuiqsut, and Kaktovik. The 
level of allowable harvest is determined under a quota system in 
compliance with the International Whaling Commission (IWC 1980; Gambell 
1982). The quota is based on the nutritional and cultural needs of 
Alaskan Natives as well as on estimates of the size and growth of the 
Bering-Chukchi-Beaufort seas stock of bowhead whales (Donovan 1982; 
Braund 1992). The AEWC allots the number of bowhead whales that each 
community is permitted to harvest. Contemporary whaling in Kaktovik 
dates from 1964 and in Nuiqsut from 1973 (EDAW/AECOM 2007; Galginaitis 
and Koski 2002). The number of boats used or owned in 2011 by the 
subsistence whaling crew of the villages of Kaktovik, Nuiqsut, and 
Barrow was 8, 12, and 40, respectively. These numbers presumably change 
from year to year.
    Bowhead harvesting in Barrow occurs both during the spring (April-
May) and fall (September-October) when the whales migrate relatively 
close to shore (ADNR 2009). During spring bowheads migrate through open 
ice leads close to shore. The hunt takes place from the ice using 
umiaks (bearded seal skin boats). During the fall, whaling is shore-
based and boats may travel up to 30 mi a day (EDAW/AECOM 2007). In 
Barrow, most whales were historically taken during spring whaling. More 
recently, however, the efficiency of the spring harvest appeared to be 
lower than the autumn harvest due to ice and weather conditions as well 
as struck whales escaping under the ice (Suydam et al. 2010). In the 
past few years the bowhead fall hunt has become increasingly important.
    Nuiqsut and Kaktovik hunters harvest bowhead whales only during the 
fall. The bowhead spring migration in the Beaufort Sea occurs too far 
from shore for hunting because ice leads do not open up nearshore (ADNR 
2009). In Nuiqsut, whaling takes place from early September through 
mid-to-late September as the whales migrate west (EDAW/AECOM 2007). 
Three to five whaling crews base themselves at Cross Island, a barrier 
island approximately 20 mi northwest of the Liberty Unit shallow 
geohazard survey area. Nuiqsut whalers harvest an average of 2 bowheads 
each year. Whaling from Kaktovik also occurs in the fall, primarily 
from late August through late September or early October (EDAW/AECOM 
2007). Kaktovik whalers hunt from the Okpilak and Hulahula rivers east 
to Tapkaurak Point (ADNR 2009). Whaling activities are staged from the 
community rather than remote camps; most whaling takes place within 12 
mi of the community (ADNR 2009). Kaktovik whalers harvest an average of 
2-3 bowhead whales each year.
(2) Beluga
    The harvest of belugas is managed cooperatively through an 
agreement between NMFS and the Alaska Beluga Whale Committee (ABWC). 
From 2005-2009, between 5 and 48 belugas were harvested annually from 
the Beaufort Sea stock (Allen and Angliss 2014); with a mean annual 
take of 25.8 animals. Both Nuiqsut and Kaktovik harvest few belugas, 
mostly opportunistically during the fall bowhead hunt.
(3) Seals
    Seals represent an important subsistence resource for the North 
Slope communities. Harvest of bearded seals usually takes place during 
the spring and summer open water season from Barrow (EDAW/AECOM 2007) 
with only a few animals taken by hunters from Kaktovik or Nuiqsut. 
Seals are also taken during the ice-covered season, with peak hunting 
occurring in February (ADNR 2009). In 2003, Barrow-based hunters 
harvested 776 bearded seals, 413 ringed seals and 12 spotted seals 
(ADNR 2009). Nuiqsut hunters harvest seals in an area from Cape Halkett 
to Foggy Island Bay. For the period 2000-2001, Nuiqsut hunters 
harvested one bearded seal and 25 ringed seals (ADNR 2009). Kaktovik 
hunters also hunt seals year-round. In 2002-2003, hunters harvested 8 
bearded seals and 17 ringed seals.

Potential Impacts to Subsistence Uses

    NMFS has defined ``unmitigable adverse impact'' in 50 CFR 216.103 
as: ``an impact resulting from the specified activity: (1) That is 
likely to reduce the availability of the species to a level 
insufficient for a harvest to meet subsistence needs by: (i) Causing 
the marine mammals to abandon or avoid hunting areas; (ii) Directly 
displacing subsistence users; or (iii) Placing physical barriers 
between the marine mammals and the subsistence hunters; and (2) That 
cannot be sufficiently mitigated by other measures to increase the 
availability of marine mammals to allow subsistence needs to be met.
    The proposed shallow geohazard survey will take place between July 
1 and September 30, 2015, with data acquisition occurring in July and 
August. The project area is located >200 mi east from Barrow, 
approximately 55 mi northeast from Nuiqsut (20 mi southeast of Cross 
Island), and 120 mi west from Kaktovik. Potential impact on the 
subsistence hunt from the planned activities is expected mainly from 
sounds generated by sonar equipment. Due to the timing of the project 
and the distance from the surrounding communities, there will be no 
effects on spring harvesting and little or no effects on the occasional 
summer harvest of beluga and subsistence seal hunts (ringed and spotted 
seals are primarily harvested in winter while bearded seals are hunted 
during July-September in the Beaufort Sea). The community of

[[Page 27920]]

Nuiqsut may begin fall whaling activities in late August to early 
September from Cross Island (northwest of the survey area).

Plan of Cooperation or Measures To Minimize Impacts to Subsistence 
Hunts

(1) Plan of Cooperation
    Regulations at 50 CFR 216.104(a)(12) require IHA applicants for 
activities that take place in Arctic waters to provide a Plan of 
Cooperation (POC) or information that identifies what measures have 
been taken and/or will be taken to minimize adverse effects on the 
availability of marine mammals for subsistence purposes.
    Hilcorp has prepared a draft POC and is currently establishing a 
dialogue to coordinate activities with the villages. A POC will include 
the aforementioned mitigation measures and includes plans for and 
results of meetings with Alaska Native communities.
    Liberty Unit was transferred to Hilcorp ownership along with the 
Northstar, Milne Point and Endicott facilities. Previously, BP 
Exploration, Alaska (BPXA) coordinated with communities and 
stakeholders regarding the Liberty Unit work during the 2014 season:
     December 13-14, 2012: Meeting with the Alaska Eskimo 
Whaling Commission (AEWC) and Whaling Captains' Associations during the 
AEWC Quarterly meeting in Anchorage.
     February 7-8, 2013: CAA discussions with AEWC and Whaling 
Captains' Associations during the AEWC Annual Convention in Barrow.
    Hilcorp plans to continue attending the above meetings and has 
engaged stakeholders and Native community members throughout 2014. A 
list of meetings follows:
     Informal engagement with AEWC--July 2014
     Meeting with Native Village of Barrow leadership--August 
2014
     Meeting with North Slope Borough (NSB) Wildlife Management 
Dept.--August 2014
     Meeting with NSB Assembly--August 2014
     Meeting with NSB Planning Commission--October 2014
     Presentation and discussion with AEWC--October 2014
     Meeting with NSB Jacob Adams and NSB Counsel--October 2014
     Cultural awareness/subsistence presentation and Q&A with 
Uum's Consulting--October 2014
    Additional pre-season meetings maybe planned if needed to address 
additional requests for coordination. Any subsistence discussions will 
be documented and forwarded to the NMFS as part of the POC.
(2) Stakeholder Engagement
    Hilcorp has begun discussions with the AEWC to develop a Conflict 
Avoidance Agreement (CAA) intended to minimize potential interference 
with bowhead subsistence hunting. Hilcorp will attend and participate 
in the CAA meetings scheduled in 2015. The CAA, when executed, will 
describe measures to minimize any adverse effects on the availability 
of bowhead whales for subsistence uses.
    The North Slope Borough Department of Wildlife Management (NSB-DWM) 
was consulted, and the project was also presented to the NSB Planning 
Commission in January 2015. Hilcorp will hold meetings with key 
stakeholders in the community of Nuiqsut, Barrow, and Kaktovik to 
present the proposed project, address questions and concerns, and 
provide them with contact information of project management to which 
they can direct concerns during the survey.
    The following are measures that Hilcorp will take to reduce impacts 
to the subsistence community:
     Hilcorp will comply with the CAA terms to address plans to 
meet with the affected community to resolve conflicts and notify the 
communities of any changes in the operation.
     Inupiat Marine Mammal Observers on board the vessels are 
tasked with looking out for whales and other marine mammals in the 
vicinity of the vessel to assist the vessel captain in avoiding harm to 
whales and other marine mammals.
     Vessels will be operated in a manner to avoid areas where 
species that are sensitive to noise or movement are concentrated at 
times when such species are concentrated.
     Communications and conflict resolution are detailed in the 
CAA. Hilcorp is planning to participate in the Communications Center 
that is operated annually during the bowhead subsistence hunt.
     Communications with the villages of Barrow, Kaktovik, and 
Nuiqsut--discuss community questions or concerns including all 
subsistence hunting activities.
(3) Future Plan of Cooperation Consultations
    Hilcorp plans to engage with the relevant subsistence communities 
regarding its future Beaufort Sea activities. With regard to the 2015 
Liberty Unit shallow geohazard survey project, Hilcorp will present the 
data on marine mammal sightings and the results of the marine mammal 
monitoring and mitigation as part of our 90-day report to the 
regulatory authorities.

Unmitigable Adverse Impact Analysis and Preliminary Determination

    NMFS considers that these mitigation measures including measures to 
reduce overall impacts to marine mammals in the vicinity of the 
proposed shallow geohazard survey area and measures to mitigate any 
potential adverse effects on subsistence use of marine mammals are 
adequate to ensure subsistence use of marine mammals in the vicinity of 
Hilcorp's proposed survey in the Beaufort Sea.
    Based on the description of the specified activity, the measures 
described to minimize adverse effects on the availability of marine 
mammals for subsistence purposes, and the proposed mitigation and 
monitoring measures, NMFS has preliminarily determined that there will 
not be an unmitigable adverse impact on subsistence uses from Hilcorp's 
proposed activities.

Endangered Species Act (ESA)

    There are two marine mammal species listed as endangered under the 
ESA with confirmed or possible occurrence in the proposed project area: 
The bowhead whale and ringed seal. NMFS' Permits and Conservation 
Division has initiated consultation with NMFS' Endangered Species 
Division under section 7 of the ESA on the issuance of an IHA to 
Hilcorp under section 101(a)(5)(D) of the MMPA for this activity. 
Consultation will be concluded prior to a determination on the issuance 
of an IHA.

National Environmental Policy Act (NEPA)

    NMFS is preparing an Environmental Assessment (EA), pursuant to 
NEPA, to determine whether the issuance of an IHA to Hilcorp for its 
2015 shallow geohazard activities may have a significant impact on the 
human environment. NMFS has released a draft of the EA for public 
comment along with this proposed IHA.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to Hilcorp for conducting shallow geohazard survey in the 
Beaufort Sea during the 2015 Arctic open-water season, provided the 
previously mentioned mitigation, monitoring, and reporting requirements 
are incorporated. The proposed IHA language is provided next.

[[Page 27921]]

    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 Authorization is valid from July 1, 2015, through 
September 30, 2015.
    (2) This Authorization is valid only for activities associated with 
Hilcorp's 2015 Beaufort Sea shallow geohazard survey. The specific area 
where Hilcorp's shallow geohazard survey will be conducted lies within 
Foggy Island Bay in the U.S. Beaufort Sea, as shown in Figure 1 of 
Hilcorp's IHA application.
    (3)(a) The incidental taking of marine mammals, by Level B 
harassment only, is limited to the following species: Bowhead whale; 
gray whale; beluga whale; ringed seal; bearded seal; and spotted seal, 
as shown in Table 4.
    (3)(b) The authorization for taking by harassment is limited to the 
following acoustic sources and from the following activities:
    (i) Sonar sources used for shallow geohazard survey; and
    (ii) Vessel activities related to the shallow geohazard survey.
    (3)(c) The taking of any marine mammal in a manner prohibited under 
this Authorization must be reported within 24 hours of the taking to 
the Alaska Regional Administrator (907-586-7221) or his designee in 
Anchorage (907-271-3023), National Marine Fisheries Service (NMFS) and 
the Chief of the Permits and Conservation Division, Office of Protected 
Resources, NMFS, at (301) 427-8401, or her designee (301-427-8418).
    (4) The holder of this Authorization must notify the Chief of the 
Permits and Conservation Division, Office of Protected Resources, at 
least 48 hours prior to the start of shallow geohazard survey (unless 
constrained by the date of issuance of this Authorization in which case 
notification shall be made as soon as possible).
(5) Prohibitions
    (a) The taking, by incidental harassment only, is limited to the 
species listed under condition 3(a) above and by the numbers listed in 
Table 4. The taking by injury or death of these species or the taking 
by harassment, injury or death of any other species of marine mammal is 
prohibited and may result in the modification, suspension, or 
revocation of this Authorization.
    (b) The taking of any marine mammal is prohibited whenever the 
required source vessel protected species observers (PSOs), required by 
condition 7(a)(i), are not onboard in conformance with condition 
7(a)(i) of this Authorization.
(6) Mitigation
    (a) Establishing Zone of Influence (ZOI)
    (i) Establish and monitor with trained PSOs a ZOI zone surrounding 
the sub-bottom profiler on the source vessel where the received level 
would be 160 dB (rms) re 1 [micro]Pa for all marine mammals.
    (ii) The sizes of the ZOI is 50 m radius from the source vessel.
    (b) Vessel Movement Mitigation:
    (i) Avoid concentrations or groups of whales by all vessels under 
the direction of Hilcorp.
    (ii) If any vessel approaches within 1.6 km (1 mi) of observed 
bowhead whales, except when providing emergency assistance to whalers 
or in other emergency situations, the vessel operator will take 
reasonable precautions to avoid potential interaction with the bowhead 
whales by taking one or more of the following actions, as appropriate:
    (A) Reducing vessel speed to less than 5 knots within 300 yards 
(900 feet or 274 m) of the whale(s);
    (B) Steering around the whale(s) if possible;
    (C) Operating the vessel(s) in such a way as to avoid separating 
members of a group of whales from other members of the group;
    (D) Operating the vessel(s) to avoid causing a whale to make 
multiple changes in direction; and
    (E) Checking the waters immediately adjacent to the vessel(s) to 
ensure that no whales will be injured when the propellers are engaged.
    (iii) When weather conditions require, such as when visibility 
drops, adjust vessel speed accordingly, but not to exceed 5 knots, to 
avoid the likelihood of injury to whales.
    (iv) In general, the survey design will start in shallow water and 
work deeper to mitigate the potential ``herding'' effect.
    (c) Mitigation Measures for Sonar Sources
    (i) Ramp-up:
    (A) A ramp up, following a cold start, can be applied if the ZOI 
has been free of marine mammals for a consecutive 30-minute period. The 
entire ZOI must have been visible during these 30 minutes. If the 
entire ZOI is not visible, then ramp up from a cold start cannot begin.
    (B) If a marine mammal(s) is sighted within the ZOI during the 30-
minute watch prior to ramp up, ramp up will be delayed until the marine 
mammal(s) is sighted outside of the ZOI or the animal(s) is not sighted 
for at least 15 minutes for pinnipeds, or 30 minutes for cetaceans.
    (C) If, for any reason, the sub-bottom profiler has been 
discontinued for a period of 10 minutes or more, ramp-up procedures 
shall be implemented. If the PSO watch has been suspended during that 
time, a 30-minute clearance of the ZOI is required prior to commencing 
ramp-up. Discontinuation of sonar activity for less than 10 minutes 
does not require a ramp-up.
    (D) The survey operator and PSOs shall maintain records of the 
times when ramp-ups start and when the sub-bottom profiler reaches full 
power.
    (ii) Power-down/Shutdown:
    (A) The sub-bottom profiler shall be immediately powered down 
whenever a marine mammal is sighted approaching close to or within the 
sub-bottom profiler at full power, but is outside the ZOI of the sub-
bottom profiler at reduced power.
    (B) If a marine mammal is already within or is about to enter the 
ZOI when first detected, the sub-bottom profiler shall be shutdown 
immediately.
    (C) After showdown for more than 10 minutes, ramp-up shall not 
start until after the marine mammal is visually seen left the ZOI; or 
15 minutes have passed after the last detection of the marine mammal 
with shorter dive durations (pinnipeds and small odontocetes); or 30 
minutes have passed after the last detection of the marine mammal with 
longer diver durations (mysticetes and large odontocetes, including 
beluga whales).
    (iii) Poor Visibility Conditions:
    (A) If during foggy conditions, heavy snow or rain, or darkness, 
the full 160 dB ZOI is not visible, the sub-bottom profiler cannot 
commence a ramp-up procedure from a full shut-down.
    (B) If the sub-bottom profiler has been operational before 
nightfall or before the onset of poor visibility conditions, they can 
remain operational throughout the night or poor visibility conditions.
    (iv) Firing Sub-bottom Profiler During Turns and Transits
    (A) Throughout the shallow geohazard survey, during turning 
movements and short transits, Hilcorp will employ the use of the lowest 
setting for the sub-bottom profiler to deter marine mammals from being 
within the immediate area of the survey. The sub-bottom profiler would 
be operated at approximately one shot per minute and would not be 
operated for longer than three hours in duration.
    (d) Mitigation Measures for Subsistence Activities:
    (i) For the purposes of reducing or eliminating conflicts between

[[Page 27922]]

subsistence whaling activities and Hilcorp's survey program, the holder 
of this Authorization will participate with other operators in the 
Communication and Call Centers (Com-Center) Program. Com-Centers will 
be operated to facilitate communication of information between Hilcorp 
and subsistence whalers. The Com-Centers will be operated 24 hours/day 
during the 2015 fall subsistence bowhead whale hunt.
    (ii) All vessels shall report to the appropriate Com-Center at 
least once every six hours, commencing each day with a call at 
approximately 06:00 hours.
    (iii) The appropriate Com-Center shall be notified if there is any 
significant change in plans. The appropriate Com-Center also shall be 
called regarding any unsafe or unanticipated ice conditions.
    (iv) Upon notification by a Com-Center operator of an at-sea 
emergency, the holder of this Authorization shall provide such 
assistance as necessary to prevent the loss of life, if conditions 
allow the holder of this Authorization to safely do so.
    (v) Hilcorp shall monitor the positions of all of its vessels and 
exercise due care in avoiding any areas where subsistence activity is 
active.
    (vi) Routing barge and transit vessels:
    (A) Vessels transiting in the Beaufort Sea east of Bullen Point to 
the Canadian border shall remain at least 5 miles offshore during 
transit along the coast, provided ice and sea conditions allow.
    (B) From August 31 to October 31, vessels in the Chukchi Sea or 
Beaufort Sea shall remain at least 20 miles offshore of the coast of 
Alaska from Icy Cape in the Chukchi Sea to Pitt Point on the east side 
of Smith Bay in the Beaufort Sea, unless ice conditions or an emergency 
that threatens the safety of the vessel or crew prevents compliance 
with this requirement. This condition shall not apply to vessels 
actively engaged in transit to or from a coastal community to conduct 
crew changes or logistical support operations.
    (C) Vessels shall be operated at speeds necessary to ensure no 
physical contact with whales occurs, and to make any other potential 
conflicts with bowheads or whalers unlikely. Vessel speeds shall be 
less than 10 knots in the proximity of feeding whales or whale 
aggregations.
    (D) If any vessel inadvertently approaches within 1.6 kilometers (1 
mile) of observed bowhead whales, except when providing emergency 
assistance to whalers or in other emergency situations, the vessel 
operator will take reasonable precautions to avoid potential 
interaction with the bowhead whales by taking one or more of the 
following actions, as appropriate:
     Reducing vessel speed to less than 5 knots within 900 feet 
of the whale(s);
     Steering around the whale(s) if possible;
     Operating the vessel(s) in such a way as to avoid 
separating members of a group of whales from other members of the 
group;
     Operating the vessel(s) to avoid causing a whale to make 
multiple changes in direction; and
     Checking the waters immediately adjacent to the vessel(s) 
to ensure that no whales will be injured when the propellers are 
engaged.
    (vii) Hilcorp shall complete operations in time to allow such 
vessels to complete transit through the Bering Strait to a point south 
of 59 degrees North latitude no later than November 15, 2015. Any 
vessel that encounters weather or ice that will prevent compliance with 
this date shall coordinate its transit through the Bering Strait to a 
point south of 59 degrees North latitude with the appropriate Com-
Centers. Hilcorp vessels shall, weather and ice permitting, transit 
east of St. Lawrence Island and no closer than 10 miles from the shore 
of St. Lawrence Island.
(7) Monitoring
    (a) Vessel-based Visual Monitoring:
    (i) Vessel-based visual monitoring for marine mammals shall be 
conducted by NMFS-approved PSOs throughout the period of survey 
activities.
    (ii) PSOs shall be stationed aboard the survey vessels through the 
duration of the surveys.
    (iii) A sufficient number of PSOs shall be onboard the survey 
vessel to meet the following criteria:
    (A) 100% monitoring coverage during all periods of survey 
operations in daylight;
    (B) Maximum of 4 consecutive hours on watch per PSO; and
    (C) Maximum of 12 hours of watch time per day per PSO.
    (iv) The vessel-based marine mammal monitoring shall provide the 
basis for real-time mitigation measures as described in (6)(c) above.
    (v) Results of the vessel-based marine mammal monitoring shall be 
used to calculate the estimation of the number of ``takes'' from the 
marine surveys and equipment recovery and maintenance program.
(b) Protected Species Observers and Training
    (i) PSO teams shall consist of Inupiat observers and NMFS-approved 
field biologists.
    (ii) Experienced field crew leaders shall supervise the PSO teams 
in the field. New PSOs shall be paired with experienced observers to 
avoid situations where lack of experience impairs the quality of 
observations.
    (iii) Crew leaders and most other biologists serving as observers 
in 2015 shall be individuals with experience as observers during recent 
seismic or shallow hazards monitoring projects in Alaska, the Canadian 
Beaufort, or other offshore areas in recent years.
    (iv) Resumes for PSO candidates shall be provided to NMFS for 
review and acceptance of their qualifications. Inupiat observers shall 
be experienced in the region and familiar with the marine mammals of 
the area.
    (v) All observers shall complete a training course designed to 
familiarize individuals with monitoring and data collection procedures. 
The training course shall be completed before the anticipated start of 
the 2015 open-water season. The training session(s) shall be conducted 
by qualified marine mammalogists with extensive crew-leader experience 
during previous vessel-based monitoring programs.
    (vi) Crew members should not be used as primary PSOs because they 
have other duties and generally do not have the same level of 
expertise, experience, or training as PSOs, but they could be stationed 
on the fantail of the vessel to observe the near field, especially the 
area around the survey vessels, and implement a power-down or shutdown 
if a marine mammal enters the safety zone (or exclusion zone).
    (vii) If crew members are to be used as PSOs, they shall go through 
some basic training consistent with the functions they will be asked to 
perform. The best approach would be for crew members and PSOs to go 
through the same training together.
    (viii) PSOs shall be trained using visual aids (e.g., videos, 
photos), to help them identify the species that they are likely to 
encounter in the conditions under which the animals will likely be 
seen.
    (ix) Hilcorp shall train its PSOs to follow a scanning schedule 
that consistently distributes scanning effort according to the purpose 
and need for observations. All PSOs should follow the same schedule to 
ensure consistency in their scanning efforts.
    (x) PSOs shall be trained in documenting the behaviors of marine 
mammals. PSOs should record the primary behavioral state (i.e., 
traveling, socializing, feeding, resting, approaching or moving away 
from vessels) and relative location of the observed marine mammals.

[[Page 27923]]

(c) Marine Mammal Observation Protocol
    (i) PSOs shall watch for marine mammals from the best available 
vantage point on the survey vessels, typically the bridge.
    (ii) Observations by the PSOs on marine mammal presence and 
activity shall begin a minimum of 30 minutes prior to the estimated 
time that the sub-bottom profiler is to be turned on and/or ramped-up. 
Monitoring shall continue during the survey operations and last until 
30 minutes after the sonar equipment stop firing.
    (iii) For comparison purposes, PSOs shall also document marine 
mammal occurrence, density, and behavior during at least some periods 
when the sonar equipment used for survey is off.
    (iv) PSOs will scan the area around the vessel systematically with 
reticle binoculars (e.g., 7 x 50 and 16-40 x 80) and with the naked 
eye. GPS unit and laptop computer(s) will also be available for PSOs 
onboard survey vessels.
    (v) Personnel on the bridge shall assist the marine mammal 
observer(s) in watching for marine mammals.
    (vi) PSOs aboard the marine survey vessel shall give particular 
attention to the areas within the marine mammal ZOI around the source 
vessel, as noted in (6)(a)(i) and (ii). They shall avoid the tendency 
to spend too much time evaluating animal behavior or entering data on 
forms, both of which detract from their primary purpose of monitoring 
the exclusion zone.
    (vii) Monitoring shall consist of recording of the following 
information:
    (A) The species, group size, age/size/sex categories (if 
determinable), the general behavioral activity, heading (if 
consistent), bearing and distance from survey vessel, sighting cue, 
behavioral pace, and apparent reaction of all marine mammals seen near 
the survey vessel (e.g., none, avoidance, approach, paralleling, etc);
    (B) The time, location, heading, speed, and activity of the vessel 
(sub-bottom profiler firing or not), along with sea state, visibility, 
cloud cover and sun glare at (I) any time a marine mammal is sighted 
(including pinnipeds hauled out on barrier islands), (II) at the start 
and end of each watch, and (III) during a watch (whenever there is a 
change in one or more variable);
    (C) The identification of all vessels that are visible within 5 km 
of the survey vessel whenever a marine mammal is sighted and the time 
observed;
    (D) Any identifiable marine mammal behavioral response (sighting 
data should be collected in a manner that will not detract from the 
PSO's ability to detect marine mammals);
    (E) Any adjustments made to operating procedures; and
    (F) Visibility during observation periods so that total estimates 
of take can be corrected accordingly.
    (vii) Distances to nearby marine mammals will be estimated with 
binoculars containing a reticle to measure the vertical angle of the 
line of sight to the animal relative to the horizon. Observers may use 
a laser rangefinder to test and improve their abilities for visually 
estimating distances to objects in the water.
    (viii) PSOs shall understand the importance of classifying marine 
mammals as ``unknown'' or ``unidentified'' if they cannot identify the 
animals to species with confidence. In those cases, they shall note any 
information that might aid in the identification of the marine mammal 
sighted. For example, for an unidentified mysticete whale, the 
observers should record whether the animal had a dorsal fin.
    (ix) Additional details about unidentified marine mammal sightings, 
such as ``blow only,'' mysticete with (or without) a dorsal fin, ``seal 
splash,'' etc., shall be recorded.
    (x) When a marine mammal is seen approaching or within the 
exclusion zone applicable to that species, the marine survey crew shall 
be notified immediately so that mitigation measures described in (6) 
can be promptly implemented.
(d) Field Data-Recording and Verification
    (i) PSOs aboard the vessels shall maintain a digital log of shallow 
geohazard survey, noting the date and time of all changes in survey 
activity (ramp-up, power-down, shutdowns, etc.) and any corresponding 
changes in monitoring radii in a software spreadsheet.
    (ii) PSOs shall utilize a standardized format to record all marine 
mammal observations and mitigation actions (sub-bottom profiler power-
downs, shut-downs, and ramp-ups).
    (iii) Information collected during marine mammal observations shall 
include the following:

(A) Vessel speed, position, and activity
(B) Date, time, and location of each marine mammal sighting
(C) Number of marine mammals observed, and group size, sex, and age 
categories
(D) Observer's name and contact information
(E) Weather, visibility, and ice conditions at the time of observation
(F) Estimated distance of marine mammals at closest approach
(G) Activity at the time of observation, including possible attractants 
present
(H) Animal behavior
(I) Description of the encounter
(J) Duration of encounter
(K) Mitigation action taken

    (iv) Data shall be recorded directly into handheld computers or as 
a back-up, transferred from hard-copy data sheets into an electronic 
database.
    (v) A system for quality control and verification of data shall be 
facilitated by the pre-season training, supervision by the lead PSOs, 
and in-season data checks, and shall be built into the software.
    (vi) Computerized data validity checks shall also be conducted, and 
the data shall be managed in such a way that it is easily summarized 
during and after the field program and transferred into statistical, 
graphical, or other programs for further processing.
(e) Passive Acoustic Monitoring
    (i) Hilcorp shall conduct passive acoustic monitoring using fixed 
hydrophone(s) to
    (A) Document ambient noise conditions;
    (B) Examine the spatial and temporal distribution of marine mammals 
based on acoustic detections of their vocalizations; and
    (C) Characterize the long-range propagation of sounds produced 
during the geohazard survey; and
    (ii) Bottom-Mounted Acoustic Sensors:
    (A) Recorders shall be capable of recording marine mammal sounds 
and making both ambient and anthropogenic noise measurements.
    (B) Two recorders be deployed near the Liberty prospect and be 
aligned with the geohazard survey line, at distances of 500 m (AMAR 
with sampling rate of 64 kHz) and 5000 m (AMAR with sampling rate of 
380 kHz) from the offshore end of the survey line.
    (C) Recorders shall be located inside of the barrier islands.
(8) Data Analysis and Presentation in Reports
    (a) Estimation of potential takes or exposures shall be improved 
for times with low visibility (such as during fog or darkness) through 
interpolation or possibly using a probability approach. Those data 
could be used to interpolate possible takes during periods of 
restricted visibility.
    (b) Hilcorp shall provide the information collected, plus a number 
of summary analyses and graphics to help NMFS assess the potential 
impacts of

[[Page 27924]]

Hilcorp's survey. Specific summaries/analyses/graphics would include:
    (i) A table or other summary of survey activities (i.e., did the 
survey proceed as planned);
    (ii) A table of sightings by time, location, species, and distance 
from the survey vessel;
    (iii) A geographic depiction of sightings for each species by area 
and month;
    (iv) A table and/or graphic summarizing behaviors observed by 
species;
    (v) A table and/or graphic summarizing observed responses to the 
survey by species;
    (vi) A table of mitigation measures (e.g., power-downs, shutdowns) 
taken by date, location, and species;
    (vii) A graphic of sightings by distance for each species and 
location;
    (viii) A table or graphic illustrating sightings during the survey 
versus sightings when the sub-bottom profiler was silent; and
    (ix) A summary of times when the survey was interrupted because of 
interactions with marine mammals.
    (c) Hilcorp shall collaborate with other industrial operators in 
the area to integrate and synthesize monitoring results as much as 
possible (such as submitting ``sightings'' from their monitoring 
projects to an online data archive, such as OBIS-SEAMAP) and archive 
and make the complete databases available upon request.
(9) Reporting
    (a) Technical report: A draft technical report will be submitted to 
the Director, Office of Protected Resources, NMFS, within 90 days after 
the end of HIlcorp's 2015 open-water shallow geohazard survey in the 
Beaufort Sea. The report will describe in detail:
    (i) Summaries of monitoring effort (e.g., total hours, total 
distances, and marine mammal distribution through the study period, 
accounting for sea state and other factors affecting visibility and 
detectability of marine mammals);
    (ii) Summaries that represent an initial level of interpretation of 
the efficacy, measurements, and observations, rather than raw data, 
fully processed analyses, or a summary of operations and important 
observations;
    (iii) Summaries of all mitigation measures (e.g., operational 
shutdowns if they occur) and an assessment of the efficacy of the 
monitoring methods;
    (iv) Analyses of the effects of various factors influencing 
detectability of marine mammals (e.g., sea state, number of observers, 
and fog/glare);
    (v) Species composition, occurrence, and distribution of marine 
mammal sightings, including date, water depth, numbers, age/size/gender 
categories (if determinable), group sizes, and ice cover;
    (vi) Data analysis separated into periods when the sub-bottom 
profiler is operating and when it is not, to better assess impacts to 
marine mammals;
    (vii) Sighting rates of marine mammals during periods with and 
without the sub-bottom profiler (and other variables that could affect 
detectability), such as:
    (A) Initial sighting distances versus survey activity state;
    (B) Closest point of approach versus survey activity state;
    (C) Observed behaviors and types of movements versus survey 
activity state;
    (D) Numbers of sightings/individuals seen versus survey activity 
state;
    (E) Distribution around the survey vessel versus survey activity 
state; and
    (F) Estimates of take by harassment;
    (viii) A clear comparison of authorized takes and the level of 
actual estimated takes;
    (ix) Cumulative sound exposure level over 24 hours 
(cSEL24), in particular during the use of the two sub-bottom 
profilers;
    (x) Ground-truth of data collected by AMARs in consultation with 
biologists experienced in Arctic species vocalizations with error rates 
for automatic detection to ensure the accurate classification of 
vocalizations by species; and
    (xi) Information of source levels and other acoustic 
characteristics of the active acoustics survey equipment, such as 
spectral content, and received levels in root-mean-squared (RMS) dB, 
sound exposure level (SEL), dB peak to peak and \1/3\ octave bands.
    (b) The draft technical report shall be subject to review and 
comment by NMFS. Any recommendations made by NMFS must be addressed in 
the final report prior to acceptance by NMFS. The draft report will be 
considered the final report for this activity under this Authorization 
if NMFS has not provided comments and recommendations within 90 days of 
receipt of the draft report.
    (c) Hilcorp will share data and work with its contractor JASCO to 
collaborate with other researchers. The passive acoustic recording 
data, including data on marine mammal vocalizations, will be made 
publically available for researchers.
    (10)(a) In the unanticipated event that survey operations clearly 
cause the take of a marine mammal in a manner prohibited by this 
Authorization, such as an injury or mortality (e.g., ship-strike, gear 
interaction, and/or entanglement), Hilcorp shall immediately cease 
survey operations and immediately report the incident to the Chief, 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
at 301-427-8401 and/or by email to Jolie.Harrison@noaa.gov and 
Shane.Guan@noaa.gov and the Alaska Regional Stranding Coordinators 
(Aleria.Jensen@noaa.gov and Barbara.Mahoney@noaa.gov). The report must 
include the following information:
    (i) Time, date, and location (latitude/longitude) of the incident;
    (ii) The name and type of vessel involved;
    (iii) The vessel's speed during and leading up to the incident;
    (iv) Description of the incident;
    (v) Status of all sound source use in the 24 hours preceding the 
incident;
    (vi) Water depth;
    (vii) Environmental conditions (e.g., wind speed and direction, 
Beaufort sea state, cloud cover, and visibility);
    (viii) Description of marine mammal observations in the 24 hours 
preceding the incident;
    (ix) Species identification or description of the animal(s) 
involved;
    (x) The fate of the animal(s); and
    (xi) Photographs or video footage of the animal (if equipment is 
available).
    Activities shall not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS shall work with Hilcorp to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Hilcorp may not resume 
their activities until notified by NMFS via letter, email, or 
telephone.
    (b) In the event that Hilcorp 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 (i.e., in less than 
a moderate state of decomposition as described in the next paragraph), 
Hilcorp will immediately report the incident to the Chief, Permits and 
Conservation Division, Office of Protected Resources, NMFS, at 301-427-
8401, and/or by email to Jolie.Harrison@noaa.gov and 
Shane.Guan@noaa.gov and the NMFS Alaska Stranding Hotline (1-877-925-
7773) and/or by email to the Alaska Regional Stranding Coordinators 
(Aleria.Jensen@noaa.gov and Barabara.Mahoney@noaa.gov). The report must 
include the same information identified in Condition 10(a) above. 
Activities may continue while NMFS reviews the circumstances of the 
incident. NMFS will work with Hilcorp to determine whether

[[Page 27925]]

modifications in the activities are appropriate.
    (c) In the event that Hilcorp 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 activities authorized in Condition 3 
of this Authorization (e.g., previously wounded animal, carcass with 
moderate to advanced decomposition, or scavenger damage), Hilcorp shall 
report the incident to the Chief, Permits and Conservation Division, 
Office of Protected Resources, NMFS, at 301-427-8401, and/or by email 
to Jolie.Harrison@noaa.gov and Shane.Guan@noaa.gov and the NMFS Alaska 
Stranding Hotline (1-877-925-7773) and/or by email to the Alaska 
Regional Stranding Coordinators (Aleria.Jensen@noaa.gov and 
Barbara.Mahoney@noaa.gov), within 24 hours of the discovery. Hilcorp 
shall provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network. Hilcorp can continue its operations under 
such a case.
    (11) Activities related to the monitoring described in this 
Authorization do not require a separate scientific research permit 
issued under section 104 of the Marine Mammal Protection Act.
    (12) The Plan of Cooperation outlining the steps that will be taken 
to cooperate and communicate with the native communities to ensure the 
availability of marine mammals for subsistence uses, must be 
implemented.
    (13) This Authorization may be modified, suspended, or withdrawn if 
the holder fails to abide by the conditions prescribed herein or if the 
authorized taking is having more than a negligible impact on the 
species or stock of affected marine mammals, or if there is an 
unmitigable adverse impact on the availability of such species or 
stocks for subsistence uses.
    (14) A copy of this Authorization and the Incidental Take Statement 
must be in the possession of each survey vessel operator taking marine 
mammals under the authority of this Incidental Harassment 
Authorization.
    (15) Hilcorp is required to comply with the Terms and Conditions of 
the Incidental Take Statement corresponding to NMFS' Biological 
Opinion.

Request for Public Comments

    NMFS requests comment on our analysis, the draft authorization, and 
any other aspect of the Notice of Proposed IHA for Hilcorp's proposed 
shallow geohazard survey in the Beaufort Sea. Please include with your 
comments any supporting data or literature citations to help inform our 
final decision on Hilcorp's request for an MMPA authorization.

    Dated: May 11, 2015.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2015-11701 Filed 5-14-15; 8:45 am]
 BILLING CODE 3510-22-P