[Federal Register: August 21, 2008 (Volume 73, Number 163)]
[Notices]
[Page 49421-49443]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21au08-31]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XJ71
Incidental Takes of Marine Mammals During Specified Activities;
Shallow Hazard and Site Clearance Surveys in the Chukchi Sea in 2008
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice of issuance of a marine mammal incidental take
authorization.
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SUMMARY: In accordance with provisions of the Marine Mammal Protection
Act (MMPA) as amended, notification is hereby given that an Incidental
Harassment Authorization (IHA) to take marine mammals, by Level B
harassment, incidental to conducting open water shallow hazard and site
clearance surveys by ConocoPhillips Alaska, Inc. (CPAI) in the Chukchi
Sea has been issued.
DATES: The authorization is effective from August 15, 2008, until
October 31, 2008.
ADDRESSES: A copy of the application, IHA, the Final Programmatic
Environmental Assessment for Arctic Ocean Outer Continental Shelf
Seismic Surveys--2006 (2006 PEA) prepared by the Minerals Management
Service (MMS), the 2008 Supplemental Environmental Assessment (SEA) for
the Issuance of five IHAs for open water seismic surveys and shallow
hazard and site clearance surveys in the Arctic, and/or a list of
references used in this document may be obtained by writing to P.
Michael Payne, Chief, Permits, Conservation and Education Division,
Office of Protected Resources, National Marine Fisheries Service, 1315
East-West Highway, Silver Spring, MD 20910-3225, or by telephoning one
of the contacts listed here (see FOR FURTHER INFORMATION CONTACT).
FOR FURTHER INFORMATION CONTACT: Shane Guan, Office of Protected
Resources, NMFS, (301) 713-2289, ext 137 or Brad Smith, Alaska Region,
NMFS, (907) 271-5006.
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 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.
Authorization shall be granted if NMFS finds that the taking will
have a negligible impact on the species or stock(s) and will not have
an unmitigable adverse impact on the availability of the species or
stock(s) for certain subsistence uses, 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.''
Section 101(a)(5)(D) of the MMPA established an expedited process
by which citizens of the United States can apply for an authorization
to incidentally take small numbers of marine mammals by 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].
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS
review of an application followed by a 30-day public notice and comment
period on any proposed authorizations for the incidental harassment of
marine mammals. Within 45 days of the close of the comment period, NMFS
must either issue or deny the authorization.
Summary of Request
On April 30, 2008, NMFS received an application from CPAI for the
taking, by Level B harassment, of several species of marine mammals
incidental to conducting shallow hazard and site clearance surveys
using acoustic equipment and small airguns in the Chukchi Sea for 30-45
days from approximately August 10, 2008 until October 31, 2008. The
geographic region of the proposed activities includes two areas spaced
about 60 km (37 mi) apart and a path for sampling conditions along a
potential pipeline route. Each area is about 2,000 km\2\ (772.5 mi\2\)
with dimensions about 72 km (45 mi) by 62 km (38.5 mi). The two areas
are about 111 km (69 mi) off the Alaska coast, generally west from the
village of Wainwright. The marine surveys will be performed from a
seismic vessel.
Detailed information on the shallow hazard and seismic surveys can
be found in the CPAI application and in the Federal Register notice for
the proposed IHA published on May 23, 2008 (73 FR 30064) (hereinafter
``FR Notice of Proposed IHA''). No changes have been made to the
proposed activities since publication of the FR Notice of Proposed IHA.
Comments and Responses
During the 30-day public comment period, NMFS received comments
from the Marine Mammal Commission (Commission), the Native Village of
Point Hope (NVPH); the North Slope Borough (NSB); the Alaska Eskimo
Whaling Commission (AEWC); the Center for Biological Diversity (CBD),
Pacific Environment, Natural Resources Defense Council and Alaska
Wilderness League; Oceana and Ocean Conservancy; the Inupiat Community
of the Arctic Slope (ICPS); Dr. David E. Bain of the University of
Washington; and CPAI.
General Comments
Comment 1: The Commission recommends that NMFS issue the IHA
provided that (a) the proposed marine mammal mitigation and monitoring
activities are carried out as described in NMFS' FR Notice of Proposed
IHA; (b) operations be suspended immediately if a dead or seriously
injured marine mammal is found in the vicinity of the operations and
the death or injury could have occurred incidental to those operations;
and (c) the list of species authorized to be taken be expanded to
include fin whales.
Response: NMFS concurs with the Commission's recommendation and
will require the immediate suspension of seismic activities if a dead
or injured marine mammal has been sighted within an area where the
Holder of the IHA deployed and utilized seismic airguns within the past
24 hours.
In addition, fin whales have been included in the list of species
authorized to be taken by Level B harassment for the CPAI shallow
hazard and site clearance surveys.
Comment 2: The NSB and ICAS point out that the CPAI application was
incomplete because the proposed dates and duration of activities vary
throughout the application documents. In addition, the NSB points out
that the application has limited information
[[Page 49422]]
about marine mammal distribution, movements, habitat use, population
size and trends. In addition, the ICAS states that CPAI cannot have
adequately provided estimates of the number and type of species taken,
when the IHA application did not adequately acknowledge the
uncertainties in the available data for this type of operation.
Response: Comment noted. NMFS reviewed the CPAI application and
verified the information provided within. At the time when CPAI
submitted its application, no specific dates had been identified by
CPAI, but a range of possible dates (i.e., July 15 through November 15,
2008) for the activity was noted. CPAI has since narrowed its operation
window to between August 10 and October 31, 2008. CPAI also indicates
that the seismic activities would take approximately 30-45 days, and it
is likely to finish the operation earlier if weather permits.
While information on marine mammals is lacking, NMFS conducted
relevant research so that complete information is provided in the FR
Notice of Proposed IHA. In addition, detailed and updated information
on bowhead whales and other marine mammal species is provided in the
MMS 2006 PEA, MMS 2007 draft PEIS, NMFS 2008 SEA, and the SAR, as
referenced in the FR Notice of Proposed IHA.
Comment 3: The NSB and ICAS recommend that NMFS not authorize
CPAI's proposed seismic activities. The CBD also urges NMFS not to
issue any take authorization to CPAI for the proposed activities unless
and until the agency can ensure that mitigation measures are in place
that truly avoid adverse impacts to all species and their habitats and
only after full and adequate public participation has occurred and
environmental review of the cumulative impacts of such activities on
these species and their habitats has been undertaken. The CBD feels
that the proposed IHA does not meet these standards and therefore
violates the MMPA, ESA, NEPA, and other governing statutes and
regulations.
Response: NMFS does not agree with NSB, ICAS, and CBD's
recommendation and CBD's assessment. In its FR Notice of Proposed IHA,
NMFS outlined in detail the proposed mitigation and monitoring
requirements. The implementation of these measures will reduce the
impacts of the proposed survey on marine mammals and their surrounding
environment to the lowest level practicable, as required by the MMPA.
The public was given 30 days to review and comment on these measures,
in accordance with section 101(a)(5)(D) of the MMPA. NMFS has prepared
a Supplemental EA to the 2006 MMS PEA. NMFS has fulfilled its
obligations under NEPA by completing a SEA, which is not required to be
available for public comment prior to its finalization. Additionally,
NMFS completed a Biological Opinion in July 2008, as required by
section 7 of the ESA, which concluded that this action is not likely to
jeopardize the continued existence of listed species or result in the
destruction or adverse modification of critical habitat. Therefore,
NMFS does not believe the issuance of an IHA to CPAI would result in a
violation of the MMPA, ESA, NEPA, and other governing statutes and
regulations.
Acoustics Impacts
Comment 4: Citing studies on noise impacts to chinchillas
(Henderson et al., 1991) and human noise exposure standards by the U.S.
Occupational Safety Health Administration (OSHA), Dr. Bain states that
``in humans, chronic exposure to levels of noise too low to generate a
TTS can result in PTS.'' As OSHA standards require limiting human
exposure to noise at 115 dBA above threshold to 15 minutes per day, Dr.
Bain concludes that this level is equivalent to 145 dB re 1 microPa for
killer whales.
Response: Although NMFS agrees that chronic exposure to noise
levels that would not cause TTS could result in hearing impairment in
the long-term, it is important to understand that such exposure has to
be of a chronic and long-term nature. The OSHA standards for
permissible exposure are based on daily impacts throughout an
employee's career, while the noise exposure to seismic surveys by
marine mammals is short-term and intermittent, as described in the FR
Notice of Proposed IHA and in the MMS 2006 PEA. In addition, the
reference Dr. Bain cites to (Henderson et al., 1991) does not address
chronic noise impact to humans. The research by Henderson et al. (1991)
focused on the applicability of the equal energy hypothesis (EEH) to
impact (impulse) noise exposures on chinchillas, and the results
indicated that hearing loss resulting from exposure to impact noise did
not conform to the predictions of the EEH, which is the basis for OSHA
standards for continuous noise exposure.
Most importantly, Dr. Bain's extrapolation of 145 dB re 1 microPa
for killer whale hearing safety from OSHA's 115 dBA is fundamentally
flawed for three reasons:
(1) The reference points when using decibel (dB) unit that address
sound in air and in water are different. For airborne sounds, such as
those by OSHA, the reference point is 20 microPa, while for underwater
sounds, the reference point is 1 microPa. There are 26 dB differences
between the values when different reference points are used for the
same sound pressure, therefore, 115 dB re 20 microPa is 141 dB re 1
microPa for the same sound pressure. So 115 dB re 20 microPa in air
above human threshold (defined as 0 dB re 20 microPa in air) would be
141 dB re 1 microPa underwater for the same sound pressure. Using the
lowest threshold of 30 dB re 1 microPa as the killer whale hearing
threshold, and assuming that noise impacts to killer whales are the
same as for humans, one could extrapolate that continuous noise
exposure of 171 dB re 1 microPa (141 dB over the 30 dB threshold) for
15 minutes for killer whales would be equivalent to humans exposed to
115 dB re 20 microPa for 15 minutes. Nevertheless, such extrapolation
still leaves much uncertainty since marine mammals have a different
mechanism for sound reception (Au, 1993; Richardson et al., 1005). Some
of the most recent science has shown that for some odontocetes, the
onset of TTS when exposed to impulse noise is much higher (Finneran et
al., 2002) than NMFS' current thresholds.
(2) The decibel values used by OSHA are expressed as broadband A-
weighted sound levels expressed in dBA. This frequency-dependent
weighting function is used to apply to the sound in accordance with the
sensitivity of the human ear to different frequencies. Thus, it is
inappropriate to compare these values to an animal's hearing
capability, including how an animal perceives sound in air (Richardson
et al., 1995). For marine mammals, M-weighting functions have been
suggested based on five different hearing functional groups to address
different hearing sensitivities of different frequencies by each of the
marine mammal groups (Southall et al., 2007).
(3) Finally, the sound characteristic used in OSHA standards is
continuous sound, while the seismic sound from the proposed shallow
hazard and site clearance surveys is impulse sound, which by its very
nature is not a continuous sound.
Comment 5: Dr. Bain asserts that the zone of immediate risk of
injury or death for marine mammals should be within the 150-215 dB re 1
microPa contours and assumes that values can be extrapolated from
terrestrial species. Dr. Bain supports his argument by stating that
immediate injury may result from
[[Page 49423]]
brief exposure to sound levels that are 120 to 140 dB above threshold
in terrestrial mammals, and that marine mammals vary in their best
sensitivity from killer whales at around 30 dB re 1 microPa (killer
whale) to 60 dB re 1 microPa (phocids) and 75 dB re 1 microPa
(otariids)
Response: NMFS does not agree with Dr. Bain's assessment. As
discussed in Response to Comment 3, the reference points when using
decibel (dB) unit that address sound in air is 20 microPa, while in
water the reference point is 1 microPa. Therefore, the decibel levels
used to address injury in terrestrial mammals cannot be extrapolated to
apply marine mammal species without adding a correction factor of 26 dB
(see Richardson et al., 1995). Even so, plenty of controlled laboratory
experiments on several marine mammal species (e.g., beluga whales,
bottlenose dolphins, harbor seals, California sea lions, and northern
elephant seals) in the past decade point out injuries (PTS) to marine
mammals would probably occur at much higher sound exposure levels, far
above the 180 and 190 dB re 1 microPa NMFS currently applies to protect
cetaceans and pinnipeds from onset of Level A harassment (injury). (see
review by Southall et al., 2007).
Comment 6: Citing OSHA (2007) standards for human noise exposure
standards, Nachtigall et al. (2003), and Henderson et al. (1991), Dr.
Bain extrapolates that permanent injury to hearing from repeated
exposure to noise at 120 dB re 1 microPa would occur to killer whales
after being exposed for 8 hours.
Response: NMFS does not agree with Dr. Bain's assessment as such an
extrapolation is invalid. First, as discussed in Response to Comment 4,
the reference point addressing sound levels or intensities in air,
which is used by OSHA for the human noise exposure standards, is
relative to 20 microPa, while the reference point used to address sound
levels or intensities in water is relative to 1 microPa. These are
fundamentally different acoustical measures and should not be confused.
Second, as discussed in Response to Comment 5, the noise exposure
standard unit used by OSHA is dBA, which is the weighted sound exposure
level based on human hearing sensitivities, and is not suitable to be
used in other animals which have very different hearing sensitivities
across the spectrum. Third, the sound sources used by OSHA are based on
continuous sound, as is the referenced paper by Nachtigall et al.
(2003), while the sound sources from the proposed seismic surveys are
impulse sounds. The prediction of acoustic injury from continuous noise
exposure is not applicable to impulse noise exposure, as is shown in
the referenced paper by Henderson et al. (1991); therefore, the
extrapolation is invalid. Fourth, ambient noise levels at many shallow
water areas could easily reach 120 dB re 1 microPa, coupled with surf
and wave actions. If killer whales suffered from permanent hearing
damage when exposed to this noise level for 8 hours as suggested by Dr.
Bain, then most killer whales in the coastal areas would have no
hearing left. The lab controlled experiments by Nachtigall et al.
(2003), as cited by Dr. Bain, show that an Atlantic bottlenose dolphin
exhibited TTS of an average 11 dB after being exposed to continued
noise up to 179 dB re 1 microPa for 55 minutes, a much higher level
than where Dr. Bain would consider TTS to occur. However, in the wild,
animals are expected to avoid such intense noise levels, thus
preventing onset of TTS. Finally, killer whales are not expected to
occur frequently in the proposed Arctic shallow hazard and site
clearance project area, so the risk to this species is minimal.
Comment 7: Citing several papers on killer whales, harbor
porpoises, and marbeled murrelets, Dr. Bain states that major behavior
changes of these animals appear to be associated with received levels
of around 135 dB re 1 microPa, and that minor behavioral changes can
occur at received levels from 90-110 dB re 1 microPa or lower. Citing
his own studies, Dr. Bain states that ``killer whales are 40% less
likely to forage at all when vessels are nearby, perhaps because vessel
noise masks echoes from prey, making the probability of foraging
successfully negligible (Bain et al. 2006ab).'' In addition, Dr. Bain
states that the threshold for effects on harbor porpoise is 90 dB re 1
microPa, for killer whale is 100 dB re 1 microPa, and for beluga whale
is 153 dB re 1 microPa, which are all lower than the threshold used to
estimate the takes. CBD also cited a study of Canadian beluga whales
showing flight responses from ice-breakers at received sound levels as
low as 94 dB. In addition, citing NRC (2003), the NVPH states that at
distances of up to 50 km from icebreakers or other ships operating in
deep channels, beluga whales respond with a suite of behavioral
reactions which include rapid swimming away from the ship for distances
up to 80 km. Finally, citing Richardson et al. (1999) and Richardson
(2008), the NSB states that bowhead whales were excluded from a zone
around an active seismic vessel where sound levels were estimated to be
between 116 and 135 dB, and that bowhead whales were deflected away
from sounds associated with a development island in the Beaufort Sea at
levels perhaps approaching ambient sound levels.
Response: NMFS does not agree with Dr. Bain, CBD, NVPH, and NSB's
assessment. Although it is possible that marine mammals could react to
any sound levels detectable above the ambient noise level within the
animals' respective frequency response range, this does not mean that
such animals would react in a biologically significant way. In
addition, as discussed in Response to Comment 5, ambient noise levels
in many of the world's ocean can easily exceed 90 dB re 1 microPa
(Urick, 1983).
According to experts on marine mammal behavior, the degree of
reaction which constitutes a ``take,'' i.e., a reaction deemed to be
biologically significant that could potentially disrupt the migration,
breathing, nursing, breeding, feeding, or sheltering, etc. of a marine
mammal is complex and context specific, and it depends on several
variables in addition to the received level of the sound by the
animals. These additional variables include, but are not limited to,
other source characteristics (such as frequency range, duty cycle,
continuous vs. impulse vs. intermittent sounds, duration, moving vs.
stationary sources, etc.); specific species, populations, and/or
stocks; prior experience of the animals (naive vs. previously exposed);
habituation or sensitization of the sound by the animals; and behavior
context (whether the animal perceives the sound as predatory or simply
annoyance), etc. (Southall et al., 2007).
The references cited by Dr. Bain, CBD, NVPH, and NSB's second
example in this comment address different source characteristics
(continuous sound rather than impulse sound that are planned for the
proposed shallow hazard and site clearance surveys) or species (killer
whales and harbor proposes) that rarely occur in the proposed Arctic
action area. No reference supporting the ``threshold for effects'' on
beluga whales is provided by Dr. Bain. Much research regarding bowhead
and gray whales response to seismic survey noises has been conducted in
addition to marine mammal monitoring studies during prior seismic
surveys. Detailed descriptions regarding behavior responses of these
marine mammals to seismic sounds are available (e.g., Richardson et
al., 1995; review by Southall et al., 2007), and are also discussed in
this document.
[[Page 49424]]
Although migrating bowhead whales were shown to be excluded from a
zone around an active seismic vessel where sound levels were estimated
to be at around 120 dB (Richardson et al., 1999), the situation in this
issue was that the migratory corridor was narrower in the Beaufort Sea.
As the 120 dB ensonified area filled the narrow migratory corridor,
thus impedes the movement of the whales. However, NMFS believes that in
the Chukchi Sea where the area is more open, the 120 dB ensonified area
would not impede bowhead whale migration. Therefore, there would be no
significant biological affect to the species. However, as discussed
below that monitoring a 120-dB radius in the Chukchi Sea is not
practicable and due to safety concerns, NMFS would not require this
level of monitoring in the Chukchi Sea.
Comment 8: Dr. Bain states that sound sources are typically divided
into continuous and pulsed categories, and that behavioral effects from
pulsed sound are likely to be independent of the repetition rate and
duty cycle, and depend primarily on the duration of the survey. Dr.
Bain further states that intermittent pulses can result in continuously
received noise when sound arrives via multiple paths, which Dr. Bain
explains as ``sound that bounces between the bottom and the surface
will take longer to reach an animal than sound traveling via a direct
path,'' and that ``noise can mask signals for a brief period before and
after it is received, meaning an almost continuous received noise can
mask signals continuously.'' Dr. Bain concludes that ``the subbottom
profilers proposed for use during the site clearance surveys, with the
very short intervals between pulses, present a risk of continuous
masking effects.''
Response: NMFS does not agree with Dr. Bain's statement on ocean
acoustics and his subsequent analysis and assessment regarding
underwater sound propagation and its effects to marine mammals. Within
the scientific community on ocean acoustics and bioacoustics, two types
of sounds are traditionally recognized: transient sounds (sounds of
relatively short duration) and continuous sounds (sounds that go on and
on). Transient sounds can be further classified into impulsive (such as
seismic airguns, explosives, pile driving) and non-impulsive (such as
military tactic sonars) sounds (Richardson et al., 1995). Other
researchers working on noise impacts to marine mammals classified sound
types into a single pulse (such as a single explosive), multiple pulses
(seismic airguns, pile driving), and nonpulses (ship, sonar) (Southall
et al., 2007). A simple way to distinguish pulses sound from nonpulses
(continuous sound included) is that the former have rapid rise-time in
relation to its extremely short duration. As mentioned in Response to
Comment 7, behavioral responses from marine mammals when exposed to
underwater noise is complex and context specific, and often depend on
the sound characteristics (such as received levels, duration, duty
cycles, frequency, etc.) and other variables.
NMFS agrees that the distinction between transient and continuous
sounds is not absolute, as continuous sound from a fast moving vessel
is often treated as transient sound in relation to a stationary or slow
moving marine mammal. Further, the distinction between pulses and
nonpulses is also not always clear as certain pulsed sound sources
(e.g., seismic airguns and explosives) may become nonpulses at greater
distances due to signal decay through reverberation and other
propagation paths. However, Dr. Bain's statement that intermittent
pulses can result in continuously received noise when sound arrives via
multiple paths is unfounded. For a marine mammal exposed to noise,
multipath propagation would expose the animal to the noise multiple
times, usually each subsequent exposure with lower sound level due to
loss of acoustic energy from surface and bottom reflections; however,
the noise arriving via multipath propagation would not become
continuous sound because the intervals between signals would always
exist. In addition, noise cannot mask a signal before or after it is
received by the animal. Noise masking of signals can only occur when
the unwanted sound (noise) interferes with the signal when received by
the animal, generally at similar frequencies (Richardson et al., 1995).
Therefore, Dr. Bain's assessment that the subbottom profilers proposed
for shallow hazard and site clearance surveys would cause continuous
masking effects to marine mammals is not supported.
Comment 9: Dr. Bain states that one characteristic of pulsed
sources is known as ``time-bandwidth'' product, and he explains that it
is ``any sound with a finite duration (that is, any real-world sound)
contains additional frequencies to the nominal frequency. That is,
pulsed sources that nominally have a frequency that is too high to
hear, may, in fact, be audible, as the source will contain lower
frequencies that are detectable.''
Response: NMFS does not agree with Dr. Bain's statement that high
frequency pulsed sources nominally contain additional frequencies that
are audible. The high frequency pulsed sources are expected to operate
within their frequency range, although some mechanical noise at lower
frequencies may be produced as a byproduct during the operation. The
mechanical noise associated with acoustic equipment is expected to be
low intensity and is not expected to result in harassment of marine
mammals. Furthermore, the term ``time-bandwidth product'' is generally
used in signal process, which is irrelevant to the proposed Arctic
seismic survey.
Comment 10: Dr. Bain states that the directionality of the sources
and whether they are on during turns would also affect the ensonified
area.
Response: All acoustic sources are downward directional, thus no
additional ensonified area would result during turns.
Comment 11: The CBD argues that NMFS analysis of the various high-
energy sound sources on marine mammals is deficient, with NMFS for the
most part simply asserting that the sound generated by these sources is
outside the hearing range of most marine mammals. The CBD further
states that even NMFS acknowledges that odontocetes such as beluga
whales can in fact hear these sounds.
Response: NMFS does not agree with the CBD statement as it does not
have scientific basis. In the FR Notice of the Proposed IHA, NMFS
stated that the 445 kHz frequency band from the Klein System 3000 dual
frequency digital side-scan sonar is outside any marine mammal species'
hearing range, therefore, there would be no effect to marine mammals
when this frequency is chosen. High frequency sounds above 200 kHz are
clearly outside the hearing ranges for any marine mammals, which is
well accepted among marine mammal bioacousticians (Richardson et al.,
1995; Southall et al., 2007). In addition, NMFS never acknowledged that
odontocetes such as beluga whales can hear sounds above 200 kHz (CBD
did not provide any reference to support its statement.) Furthermore,
the sound generated by various side-scan sonars operated at the
frequency of 120 kHz and beyond produce signals above the hearing
ranges for mysticetes, such as bowhead, gray, humpback, and minke
whales (Richardson et al., 1995; Southall et al., 2007).
MMPA Comments
Comment 12: The CBD, ICAS, and NSB state that since NMFS has not
promulgated any regulations related to shallow hazard and site
clearance surveys under the MMPA, and because
[[Page 49425]]
such surveys and associated activities carry the real potential of
injury or death to marine mammals, neither an IHA nor an LOA can be
issued for CPAI's proposed activities.
Response: NMFS does not agree with the CBD, ICAS, and NSB's
statement. Section 101(a)(5)(D) of the MMPA authorizes Level A (injury)
harassment and Level B (behavioral) harassment takes. While NMFS'
regulations indicate that a LOA must be issued if there is a potential
for serious injury or mortality, NMFS does not believe that CPAI's
shallow hazard and site clearance survey requires a LOA. As explained
throughout this Federal Register Notice, it is highly unlikely that
marine mammals would be exposed to sound pressure levels (SPLs) that
could result in serious injury or mortality. The best scientific
information indicates that an auditory injury is unlikely to occur as
apparently sounds need to be significantly greater than 180 dB for
injury to occur (Southall et al., 2007).
NMFS has determined that exposure to several seismic pulses at
received levels near 200 205 dB (rms) might result in slight temporary
threshold shift (TTS) (which is not considered injury) in hearing in a
small odontocete, assuming the TTS threshold is a function of the total
received pulse energy. Received levels of 200 205 dB or more from the
loudest acoustic device would be restricted to a radius of no more than
5 m (16 ft) around a seismic vessel. CPAI's airgun array is considered
to be of small size. For baleen whales, while there are no data, direct
or indirect, on levels or properties of sound that are required to
induce TTS, there is a strong likelihood that baleen whales (bowhead
and gray whales) would avoid the approaching airguns (or vessel) before
being exposed to levels high enough for there to be any possibility of
onset of TTS. For pinnipeds, information indicates that for single
seismic impulses, sounds would need to be higher than 190 dB rms for
TTS to occur while exposure to several seismic pulses indicates that
some pinnipeds may incur TTS at somewhat lower received levels than do
small odontocetes exposed for similar durations. Consequently, NMFS has
determined that it would be lawful to issue an IHA to CPAI for the 2008
seismic survey program.
Comment 13: The CBD states that it referenced the scientific
literature linking seismic surveys with marine mammal stranding events
in its comments to MMS on the 2006 Draft PEA and in comments to NMFS
and MMS on the 2007 DPEIS. The CBD further states that NMFS' failure to
address these studies and the threat of serious injury or mortality to
marine mammals from seismic surveys renders NMFS' conclusory
determination that serious injury or morality will not occur from
CPAI's activities arbitrary and capricious.
Response: The MMS briefly addressed the humpback whale stranding in
Brazil on page PEA-127 in the 2006 Final PEA. Marine mammal strandings
are also discussed in the MMS 2007 DPEIS. A more detailed response to
the cited strandings has been provided in several previous IHA issuance
notices for seismic surveys (e.g., 73 FR 40512, July 15, 2008).
Additional information has not been provided by CBD or others regarding
these strandings. As NMFS has stated, the evidence linking marine
mammal strandings and seismic surveys remains tenuous at best. Two
papers, Taylor et al. (2004) and Engel et al. (2004), reference seismic
signals as a possible cause for a marine mammal stranding. Taylor et
al. (2004) noted two beaked whale stranding incidents related to
seismic surveys. The statement in Taylor et al. (2004) was that the
seismic vessel was firing its airguns at 1300 hrs on September 24,
2004, and that between 1400 and 1600 hrs, local fishermen found live-
stranded beaked whales some 22 km (12 nm) from the ship's location. A
review of the vessel's trackline indicated that the closest approach of
the seismic vessel and the beaked whales' stranding location was 33 km
(18 nm) at 1430 hrs. At 1300 hrs, the seismic vessel was located 46 km
(25 nm) from the stranding location. What is unknown is the location of
the beaked whales prior to the stranding in relation to the seismic
vessel, but the close timing of events indicates that the distance was
not less than 33 km (18 nm). No physical evidence for a link between
the seismic survey and the stranding was obtained. In addition, Taylor
et al. (2004) indicates that the same seismic vessel was operating 500
km (270 nm) from the site of the Galapagos Island stranding in 2000.
Whether the 2004 seismic survey caused two beaked whales to strand is a
matter of considerable debate (see Cox et al., 2004). NMFS believes
that scientifically, these events do not constitute evidence that
seismic surveys have an effect similar to that of mid-frequency
tactical sonar. However, these incidents do point to the need to look
for such effects during future seismic surveys. To date, follow-up
observations on several scientific seismic survey cruises have not
indicated any beaked whale stranding incidents.
Engel et al. (2004), in a paper presented to the International
Whaling Commission (IWC) in 2004 (SC/56/E28), mentioned a possible link
between oil and gas seismic activities and the stranding of eight
humpback whales (seven off the Bahia or Espirito Santo States and one
off Rio de Janeiro, Brazil). Concerns about the relationship between
this stranding event and seismic activity were raised by the
International Association of Geophysical Contractors (IAGC). The IAGC
(2004) argues that not enough evidence is presented in Engel et al.
(2004) to assess whether or not the relatively high proportion of adult
strandings in 2002 is anomalous. The IAGC contends that the data do not
establish a clear record of what might be a ``natural'' adult stranding
rate, nor is any attempt made to characterize other natural factors
that may influence strandings. As stated previously, NMFS remains
concerned that the Engel et al. (2004) article appears to compare
stranding rates made by opportunistic sightings in the past with
organized aerial surveys beginning in 2001. If so, then the data are
suspect.
Second, strandings have not been recorded for those marine mammal
species expected to be harassed by seismic in the Arctic Ocean. Beaked
whales and humpback whales, the two species linked in the literature
with stranding events with a seismic component are either extralimital
or not located in the Chukchi Sea where shallow hazard and site
clearance survey would occur. Moreover, NMFS notes that in the Arctic,
marine mammal observation and monitoring have been conducted by the
industry during periods of industrial activity (and by MMS during times
with no activity). No strandings or marine mammals in distress have
been observed during these surveys; nor reported by NSB inhabitants.
Finally, if bowhead and gray whales react to sounds at very low levels
by making minor course corrections to avoid seismic noise and
mitigation measures require CPAI to ramp-up the seismic array to avoid
a startle effect, strandings are highly unlikely to occur in the Arctic
Ocean. Ramping-up of the array will allow marine mammals the
opportunity to vacate the area of ensonification and thus avoid any
potential injury or impairment of their hearing capabilities. In
conclusion, NMFS does not expect any marine mammals will incur serious
injury or mortality as a result of CPAI's shallow hazard and site
clearance survey in the Chukchi Sea in 2008.
Comment 14: The CBD states that NMFS failed to adequately specify
[[Page 49426]]
CPAI's activities and impacts of vessels because neither CPAI's
application nor NMFS' FR Notice of the Proposed IHA mention the various
transit routes through U.S. waters in the Bering, Chukchi and/or
Beaufort Seas that these vessels associated with CPAI's surveys would
take.
Response: The specified activity that has been proposed and for
which an IHA has been requested is the use of seismic airguns to
conduct oil and gas exploration. While the support vessels play a role
in facilitating seismic operations, NMFS does not expect these
operations to result in the incidental take of marine mammals. Since
these support vessels are typically slow-moving, any risk of vessel
collisions with marine mammals is expected to be minimal. Moreover,
normal shipping and transit operations do not rise to a level requiring
an authorization under the MMPA. To require IHAs and LOAs for standard
shipping would affect NMFS' ability to review activities that have a
potential to cause harm to marine mammal populations.
Comment 15: The ICAS and NSB state that a ``small take'' finding is
inadequate and thus cannot be supported with actual data for the
proposed CPAI shallow hazard and site clearance survey, therefore,
placing NMFS in the position of having to make an arbitrary decision.
In addition, the CBD states that NMFS did not make the distinction
between ``small number'' and ``negligible impact'' while making the
decision in the FR Notice of the Proposed IHA.
Response: NMFS does not agree with the ICAS, NSB, and CBD's
statement. The analysis provided in the FR Notice of Proposed IHA
clearly described in detail the numbers of bowhead, gray, and beluga
whales, and ringed and bearded seals that may be potentially taken by
Level B harassment as a result of the seismic operations in the Chukchi
Sea. As clearly stated in the aforementioned Federal Register notice,
take numbers of these species represent 0.09, 0.19, and 0.06 percent of
the western Arctic stock of bowhead (population estimated at 10,545),
eastern North Pacific stock of gray (population estimated at 18,178),
and the Bering Sea stock of harbor porpoises (population estimated at
66,078), respectively; and 0.55 and 0.15 percent of the Alaska stocks
of ringed (population estimated at 249,000 in the Chukchi Sea) and
bearded seal (population estimated at 250,000-300,000 in the Bering and
Chukchi Seas) populations within the Chukchi Sea, respectively.
Although no take number was estimated for humpback, fin, minke, and
killer whales, harbor porpoises, and spotted and ribbon seals in the
vicinity of the project area due to their rare presence based in the
Chukchi Sea, NMFS believes that the harassment of these species would
be much less likely than those of bowhead and beluga whales and ringed
and bearded seals. NMFS believes that the numbers for all affected
species are small relative to their stock size. Separate detailed
analyses on the levels of take by noise exposure and cumulative impacts
to these marine mammal species and stocks from a wide spectrum in the
past, current, and foreseeable future were also conducted and described
in the aforementioned Federal Register notice, the MMS 2006 PEA, and
NMFS 2008 SEA. These analyses led NMFS to conclude that while
behavioral modifications, including temporarily vacating the area
during the project period may be made by these species to avoid the
resultant visual and acoustic disturbance, NMFS nonetheless found that
this action would result in no more than a negligible impact on the
affected marine mammal species and/or stocks. NMFS also found that the
proposed action would not have an unmitigable adverse impact on the
availability of such species or stocks for taking for subsistence uses.
Comment 16: The CPAI states although for bowhead whales a current
minimum population is estimated at 9,472, there are more data that
gives a range of the population up to 13,000 individuals. CPAI requests
NMFS to consider using the range that more accurately reflects the
health of the population and its increased growth over the past few
decades.
Response: Comment noted. Although several recent studies have put
the western Arctic stock of bowhead whales in the range of 13,000
individuals (Gerber et al., 2007; Citta et al., 2007), those studies
were based on the projection of an approximate 3 percent increase from
the most recent estimate conducted in 2004 (George et al., 2004).
However, it is important to recognize that this number (13,000) is
merely a projection based on the stock assessment survey and does not
represent the population estimate which is usually based on population
abundance surveys. NMFS Stock Assessment Report defines the best stock
estimate for the western Arctic bowhead whales at 10,545, the minimum
at 9,472 individuals, respectively (Angliss and Outlaw, 2008). For the
purpose of this activity, NMFS uses the best population estimate, i.e.,
10,545.
Comment 17: The ICAS points out that the population density
estimates used in the IHA application to determine the estimated take
of various species are uncertain because CPAI based population density
estimates on the published report of marine mammal surveys conducted
during the Shell and CPAI seismic program in the Chukchi Sea during
2007 (``LGL Report''). The ICAS further states that while these may be
the most recent density estimates for the region, they do not include
estimates for ribbon seals, beluga, humpback whales, or fin whales.
Finally, the ICAS points out that only 22 percent of the total daylight
observation effort from the main vessel, and 43 percent of the total
daylight observation from chase/monitoring vessels for the Chukchi Sea
survey was useable.
Response: As ICAS states in its comment these are the most recent
density estimates of marine mammal species/stocks in the vicinity of
the proposed seismic survey area. Therefore, NMFS considers these data
to best reflect the recent marine mammal distribution and abundance in
the region. These density estimates were adjusted for sighting rates to
account for animals present but not actually seen. As for those species
and stocks whose density data are not available, such as beluga,
humpback, and killer whales, and ribbon seals that could also be
affected by Level B behavioral harassment, since the occurrence of
these marine mammals is very rare within the proposed project area
during the late summer and fall in the Chukchi Sea, take numbers cannot
be estimated. However, should these animals occur in the project area,
NMFS believes their take numbers would be much lower (including as a
percentage of the affected species or stock) as compared to those
marine mammals whose take numbers were calculated.
Comment 18: The CBD, ICAS, and NSB state that NMFS' estimates of
the number of marine mammals that may be harassed based on the
assumption that sounds below 160 dB re 1 microPa (rms) do not
constitute harassment is incorrect because an activity can constitute
harassment if it has the ``potential'' to affect marine mammal
behavior. In addition, the CBD argues that 160 dB threshold for belugas
is similarly flawed, as it points out in previous IHA notices, NMFS has
acknowledged the impacts of sounds on beluga even at significant
distances from a sound source (up to 20 km).
Response: NMFS does not agree with CBD, ICAS, and NSB's statement.
As stated in the MMPA, Level B harassment is defined as any act of
[[Page 49427]]
pursuit, torment, or annoyance which ``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.'' Activities that
affect marine mammal behavior briefly but not cause disruption of
behavioral patterns are not considered ``takes.''
In addition, in regard to impacts to marine mammal behaviors,
distance is not the only factor that counts. The received levels at
which marine mammals are affected are related to a number of factors
including source levels, distances, and acoustic propagation pathways.
The particular example CBD brought up regarding the seismic surveys by
the National Science Foundation used airgun arrays with total discharge
volume of 2,840 in\3\, while the proposed CPAI shallow hazard and site
clearance survey would only use an airgun array with total discharge
volume of 40 in\3\. The different source levels determine the
ensonified zone where marine mammals, including beluga whales, would be
impacted.
Comment 19: The ICAS points out that when calculating the estimated
take number, CPAI used the equation of multiplying the average density
of species by the length of trackline shots (in km) by twice of the
distance of transmission loss to 160 dB. The ICAS states that such
calculation did not include marine mammal takes within the semi-
circular areas defined by the safety radii that would bound the start
and end-points of seismic surveying. The ICAS states that to account
for this discrepancy, the above equation should be supplemented with
the semi-circular areas.
Response: Comment noted. Although it is customary to include the
semi-circular areas defined by the safety radii that would bound the
start and end-points of seismic surveying, the 160-dB distance is very
short due to the overall low intensity of the acoustic sources.
Therefore, the ensonified area within the bounded semi-circular areas
is very small (8 km\2\, or 0.045 percent of the total ensonified area)
when compared to the total ensonified area even without the semi-
circular areas (17,649 km\2\). A recalculation of the estimated takes
including the semi-circular areas did not show a difference from the
original calculation.
Comment 20: The CBD, ICAS, and NSB state that NMFS has no idea of
the actual population status of several of the species subject to the
proposed IHA. For example, in the most recent Stock Assessment Reports
(SARs) prepared pursuant to the MMPA, NMFS acknowledges it has no
accurate information on the status of ribbon, spotted, bearded, and
ringed seals. CBD and NSB both indicate that without these data, NMFS
cannot conclude that surveys which will harass untold numbers of
individuals of each species would have no more than a ``negligible
impact'' on the stocks.
Response: As required by the MMPA implementing regulations at 50
CFR 216.102(a), NMFS has used the best scientific information available
in making its determinations required under the MMPA. The Alaska SAR
provides population estimates based on past survey work conducted in
the region, and the SAR shows that based on the most recent
information, all of these Alaska stocks of ice seal species have robust
populations. The proposed survey by CPAI is not expected to have
adverse impacts on ice seals. The activity will last for approximately
30-45 days in the open-water environment of the Chukchi Sea, where
bearded and spotted seals are found only occasionally.
In addition, it is expected that approximately 1,379 ringed and 376
bearded seals would be affected by Level B behavioral harassment as a
result of the proposed shallow hazard and site clearance surveys,
respectively, and that these take numbers represent 0.55 and 0.15
percent of the Alaska stocks of ringed and bearded seal populations
within the Chukchi Sea, respectively. Although spotted and ribbon seals
could also be taken by Level B behavioral harassment as a result of the
proposed marine surveys in the Chukchi Sea, the probability of take is
very low since their presence is very rare within the proposed project
area. Nonetheless, NMFS believes their take numbers would be much lower
as compared to those marine mammals whose take numbers were calculated.
Comment 21: Citing research on long term adverse effects to whales
and dolphins from whale watching activities (Trites and Bain, 2000;
Bain, 2002; Lusseau et al., 2006), Dr. Bain states that Level B
behavioral harassment could be the primary threat to cetacean
populations.
Response: Although NMFS agrees that long-term, persistent, and
chronic exposure to Level B harassment could have a profound and
significant impact on marine mammal populations, such as described in
the references cited by Dr. Bain, however, those examples do not
reflect the impacts of seismic surveys to marine mammals for the
proposed CPAI project. First, whale watching vessels are intentionally
targeting and making close approaches to cetacean species so the
tourists onboard can have a better view of the animals. Some of these
whale/dolphin watching examples cited by Dr. Bain occurred in the
coastal waters of the Northwest Pacific between April and October and
for extended periods of time (``[r]ecreational and scientific whale
watchers were active by around 6 a.m., and some commercial whale
watching continued until around sunset.'') Thus multiple vessels have
been documented to be in relatively close proximity to whales for about
12 hours a day, six months a year, not counting some ``out of season''
whale watching activities and after dark commercial filming efforts. In
addition, noise exposures to whales and dolphins from whale watching
vessels are probably significant due to the vessels' proximity to the
animals. To the contrary, the proposed 2008 open water shallow hazard
and site clearance surveys, along with other potential four seismic
activities and existing industrial operations in the Chukchi and
Beaufort Seas, do not intentionally approaching marine mammals in the
project areas. The two areas situate in a much larger Arctic Ocean
Basin which is far away from most human impacts. Therefore, the adverse
effects from each activity are remote and spread farther apart, as
analyzed in the MMS 2006 PEA and draft EIS. The proposed seismic
activities would only be conducted between August and October for 30-45
days, weather permitting. In addition, although studies and monitoring
reports from previous seismic surveys have detected Level B harassment
of marine mammals, such as avoidance of certain areas by bowhead and
beluga whales during the airgun firing, no evidence suggests that such
behavioral modification is biologically significant or non-negligible
(Malme et al., 1986; 1988; Richardson et al., 1987; 1999; Miller et
al., 1999; 2005), as compared to those exposed by chronic whale
watching vessels cited by Dr. Bain. Therefore, NMFS believes that
potential impacts to marine mammals in the Arctic by shallow hazard and
site clearance surveys would be limited to Level B harassment only, and
due to the limited scale and remoteness of the projects in relation to
a large area, such adverse effects would not accumulate to the point
where biologically significant effects would realized.
Comment 22: Dr. Bain states that changes in behavior resulting from
noise exposure could lead to indirect injury in marine mammals in the
wild. He presented several examples to suggest that marine mammals
repeatedly
[[Page 49428]]
exposed to Level B behavioral harassment could result in Level A takes:
(1) Gas bubble lesions in beaked whales due to acoustically mediated
bubble growth or rapid ascent by animals after deep diving; (2) a minke
whale and harbor porpoises were observed traveling at high speed during
exposure to mid-frequency sonar in Haro Strait in 2003, and that
exhaustion from rapid flight could lead to heart or other muscle
damage, which could cause mortality; (3) citing MMS' (2004)
Environmental Assessment on Proposed Oil and Gas Lease Sale 195 in the
Beaufort Sea Planning Area (OCS EIS/EA MMS 2004-028) that feeding
requires a prey density of 800 mg/m3 and his own observation, Dr. Bain
is concerned displacement from high productive feeding areas would
negatively affect individual whales, and that small cetaceans such as
harbor porpoises would face a risk of death if they are unable to feed
for periods as short as 48-72 hours; (4) individual killer whales have
been observed splitting their pod when frightened by sonar, and that
other killer whales' separation from their social units has resulted in
death; (5) TTS may lead to harm as a minke whale was nearly struck by a
research vessel in the area where one had been observed fleeing mid-
frequency sonar; and (6) impaired auditory ability may increase
predation as white-sided dolphins were attacked by killer whales due to
the noise of the research vessel caused the approach of killer whales
undetected by the dolphins.
Response: NMFS agrees that it is possible that changes in behavior
or auditory masking resulting from noise exposure could lead to injury
in marine mammals under certain circumstances in the world, such as
those examples/hypotheses raised by Dr. Bain. However, it is not likely
that received sound pressure levels (SPLs) from the shallow hazard and
site clearance surveys would drastically cause changes in behavior or
auditory masking in marine mammals in the vicinity of the proposed
action area. First, marine mammals in the aforementioned examples and
hypotheses were exposed to high levels of non-pulse intermittent sounds
such as the military sonar, which has been shown to cause flight
activities (e.g., Haro Strait killer whales); and continuous sounds
such as the vessel, which could cause auditory masking when animals are
closer to the source. The sources produced by the acoustic equipment
and airguns for the proposed shallow hazard and site clearance surveys
are impulse sounds used in seismic profiling, bathymetry, and seafloor
imaging. Unlike military sonar, seismic pulses have an extremely short
duration (tens to hundreds milliseconds), and relatively long intervals
(several seconds) between pulses. Therefore, the sound energy levels
from these acoustic equipment and small airguns are far lower in a
given time period. Second, the intervals between each short pulse would
allow the animals to detect any biologically significant signals, and
thus avoid or prevent auditory masking. In addition, NMFS requires
mitigation measures to ramp up acoustic sources at a rate of no more
than 6 dB every 5 minutes. This ramp up would prevent marine mammals
from being exposed to high level noises without warning, thereby
eliminating the possibility that animals would dramatically alter their
behavior (i.e. from a ``startle'' reaction). NMFS also believes that
long-term displacement of marine mammals from a feeding area is not
likely because the seismic vessel is constantly moving, and the maximum
160-dB ensonified radius is about 4 km, which would make an ensonified
zone of approximately 50 km2 at any given moment, which constitutes a
very small portion of the Chukchi Sea. In reality, NMFS expects the
160-dB ensonified zone to be smaller due to absorption and attenuation
of acoustic energy in the water column.
Comment 23: Citing that the difference between takes by subsistence
harvest and potential biological removal (PBR) of the Western Arctic
stock bowhead whales is about 28 individuals whales, or less than 0.3
percent of the population, Dr. Bain is concerned that the cumulative
effects of multiple seismic surveys would not need to be very large to
push takes over PBR for bowheads.
Response: NMFS does not agree with Dr. Bain's assessment. None of
the five proposed 2008 open water Arctic seismic surveys and shallow
hazard and site clearance surveys is expected to result in any Level A
harassment (i.e., injury) or mortality. As analyzed in the NMFS 2008
supplemental environmental assessment (SEA) for the issuance of five
Arctic seismic surveys and shallow hazard and site clearance surveys,
all incidental takes of marine mammals are expected to be Level B
behavioral harassment (NMFS, 2008). Therefore, no PBR would be applied
for the proposed CPAI seismic activities and other 2008 seismic
activities in the Chukchi and Beaufort Seas.
Comment 24: Citing MMS 2006 Programmatic Environmental Assessment
(MMS 2006 PEA) and the MMS 2007 draft Programmatic Environmental Impact
Statement (DEIS) for seismic surveys in the Arctic Ocean, Dr. Bain
states that he supports the mitigation measures established in these
documents that no more than 12 cow/calf pairs and aggregation of
feeding or resting bowheads are within the area to be ensonified by 120
dB and 160 dB, respectively. The CBD also states that the monitoring of
a 120 dB safety zone for bowhead cow/calf pairs and monitoring of a 160
dB safety zone for large groups of bowhead or gray whales (> 12
individuals) were required by NMFS in 2006 and were practicable. The
CBD states that the failure to require such conditions, or at least
analyze it, violates the MMPA. Dr. Bain presumes that these numbers
(using 120 and 160 dBs) reflect the difference between takes allocated
to hunters and the PBR for the stock. Dr. Bain further suggests that
this number be applied to all seismic activities combined, not
individual seismic surveys, thus, if four seismic surveys occur
concurrently, no single survey should be allowed to affect the
migration of more than 3 cow/calf pairs or 3 aggregation of feeding or
resting bowhead whales.
Response: First, the additional mitigation measures in the MMS 2006
PEA and the MMS 2007 draft PEIS, as well as in the 2007 NMFS SEA for
the issuance of an IHA to Shell Offshore Inc. for its open water
seismic surveys conducted in the Chukchi and Beaufort Seas in 2007,
establish safety (shut-down) zones of 120 dB re 1 microPa for an
aggregation of four or more bowhead cow/calf pairs and 160 dB re 1
microPa for an aggregation of 12 or more bowhead or gray whales, not 12
cow/calf pairs as Dr. Bain states in his comment. The rationale for
this cautious and conservative approach when addressing the 120-dB and
160-dB safety zones is clearly stated in the MMS 2006 PEA. These
additional mitigation and monitoring measures were identified through
the analyses to further reduce the potential for adverse environmental
impacts and, depending on the scope of seismic-survey activities, could
be adopted as requirements for seismic-survey-related marine mammal
incidental take authorizations. With respect to CBD's concern that
these measures were ``practicable'' in 2006, NMFS has re-evaluated the
practicability of requiring aerial monitoring to the 120-dB isopleth in
the Chukchi. NMFS has determined that it is not practicable to conduct
aerial monitoring to the 120-dB isopleth because aerial surveys have
currently been determined to be impracticable
[[Page 49429]]
due to lack of adequate landing facilities, the prevalence of fog and
other inclement weather in that area, thereby resulting in safety
concerns. Additionally, these conditions are analyzed in NMFS' 2008
SEA. These numbers have nothing to do with the PBR of the bowhead whale
stock, as assumed by Dr. Bain. As discussed in FR Notice of Proposed
IHA, the proposed 2008 Arctic seismic surveys and shallow hazard and
site clearance surveys are not expected to result in Level A harassment
(injury) or mortality.
In addition, Dr. Bain's suggestion of ``breaking up'' the
aggregated takes of bowheads into small subsets that can be
``allocated'' to each seismic survey is based on his assumption that
these numbers were set by PBR. NMFS does not support this suggestion
because it has no scientific support other than assumption. The safety
zones of 120-dB for four or more cow/calf pairs and 160-dB for an
aggregation of 12 bowhead or gray whales are based on the biology of
the bowhead and gray whales as analyzed in the MMS 2007 draft PEIS.
The threshold of four or more fall-migrating bowhead whale cow/calf
pairs was set based on the following: (a) cow/calf pairs are identified
as the most vulnerable portion of the population and disruption of
their biologically significant behaviors or their avoidance of
important habitats is more likely to lead to population level impacts;
(b) mitigation measures for this portion of the population should be
cautiously developed to ensure that takings are at the lowest
practicable level and that significance is avoided; (c) bowhead whale
cow/calf pairs migrate in groupings or pulses and the observed presence
of cow/calf pairs by surveys generally indicates that additional cow/
calf pairs are present but unseen; (d) using professional judgment,
NMFS and MMS have determined that the presence of four or more cow/calf
pairs (as observed during surveys) indicates that enough cow/calf pairs
are likely present (but some unseen) in the area in numbers equal to or
greater than 12 animals; and (e) the potential for significance to
occur therefore increases when four or more bowhead whale cow/calf
pairs are observed (MMS, 2007).
The threshold of an aggregation of 12 or more bowhead or gray
whales is based on the following premises: (a) whales aggregate in
order to communicate and perform ``biologically significant'' behaviors
(as defined by NRC, 2005), such as feeding, resting, socializing,
mating, and calving; (b) aggregations of animals can also indicate an
area of preferred habitat and locations where biologically significant
behaviors are likely occurring; (c) disruptions of these biologically
significant behaviors and important habitats have a greater potential
to lead to population level effects (i.e., result in limiting
reproductive potential or recruiting success, impeding important
mother/calf bonding); (d) protective measures should be designed to
reduce the potential for disruption of biologically significant
behaviors or help ensure whales do not avoid important key habitat
areas (and thus potentially negate a negligible impact finding under
the MMPA); and (e) standard scientific acceptance that the presence of
observed whales (i.e., at the surface) during monitoring surveys
indicates that additional whales are also present in the area but non-
detectable (i.e., below the surface) (MMS, 2007).
Comment 25: Dr. Bain is concerned that the North Pacific right
whale is excluded from consideration for the proposed seismic activity
in the Chukchi Sea. Citing Nowacek et al. (2004), Dr. Bain further
states that the [North] Atlantic right whale is less easily disturbed
[than the North Pacific right whale], is known to be affected by
received levels below 135 dB.
Response: NMFS does not agree with Dr. Bain and believes his
concern is unwarranted. The North Pacific right whales are found in the
northern part of the Pacific, such as the Bering Sea and the Gulf of
Alaska (Moore et al.; 2000; 2002; LeDuc et al., 2001; Waite et al.,
2003; Mellinger et al., 2004; Wade et al., 2006). They do not enter
Chukchi Sea in the Arctic Ocean, where the proposed seismic activity is
planned. In addition, NMFS is not able to verify Dr. Bain's statement
that the North Atlantic right whale is less easily disturbed than the
North Pacific right whale, since he did not provide a supporting
reference.
Comment 26: Dr. Bain is concerned that many species are sedentary,
territorial, or have strong tendencies toward site fidelity, and that
these species are unlikely to move away from a noise source. In
addition, Dr. Bain is concerned that many predators are used to
experiencing pain during feeding, and hence tolerate pain [from being
exposed to loud noise] rather than abandoning their prey (e.g., many
mammals involved in fishery-interactions).
Response: First, the monitoring and mitigation measures described
in this document and implemented for the proposed open water seismic
activity would prevent any marine mammals from being exposed to
received levels that could cause onset of injury (180 dB re 1 microPa
for cetaceans and 190 dB re 1 microPa for pinnipeds). Second, there are
no sedentary marine mammals. The proposed seismic activity is
fundamentally different from commercial fisheries activity in which the
appearance of a seismic vessel does not reinforce the marine mammal
with food or prey, therefore, it is unlikely that predatory marine
mammals would approach the seismic vessel or acoustic source while
searching for prey. Even if a marine mammal happens to be in close
vicinity of the vessel or source, monitoring and mitigation measures
will required the crew to power-down or shut-down the acoustic sources
so that the animal will not be affected by Level A harassment.
Comment 27: Dr. Bain comments on NMFS' and CPAI's method of
calculating estimated take numbers of marine mammals by multiplying the
``strip width'' by the length of the survey, and states that ``[f]or
bowheads, some studies showed behavioral changes in nearly all whales
out to 20 km, and in many cases to at least 30 km.'' Dr. Bain further
states that ``belugas and bowheads are known to be affected at 10-20 km
or more.'' At such, Dr. Bain observes that the ramp-up procedures would
not be effective as it would take about 5 hours for the bowheads [near
the source] to move to a distance of 30 km, and marine mammal
monitoring over a distance of 20 km is very difficult.
Response: First, the estimated takes of marine mammals were
calculated by multiplying the expected average animal densities by the
area of ensonification for the 160 dB re 1 microPa (rms) isopleth for
marine mammals. The area of ensonification was determined by
multiplying the total proposed trackline (5,300 km or 3,294 mi) times 2
(both sides of the trackline) times the distance to the 160-dB isopleth
(not ``strip width,'' a term usually used in the population survey, as
stated by Dr. Bain in his comment).
NMFS cannot verify Dr. Bain's statement that ``some studies showed
behavioral changes in nearly all whales out to 20 km, and in many cases
to at least 30 km'' and that ``belugas and bowheads are known to be
affected at 10-20 km or more,'' since he did not provide any supporting
references. Neither did Dr. Bain provide the source levels and
displacement volumes of the airgun arrays in which these studies were
conducted, nor the severity of the behavioral changes by the whales.
Nevertheless, it is important to understand that the distance from the
seismic sources where bowheads or other marine mammals can be affected
depends on the source levels of the
[[Page 49430]]
airgun arrays, which is also related to the size, or displacement
volume of the airgun array. It is possible that if a large airgun array
was used in the seismic survey, the received level at 20 to 30 km
distance could still be high enough to cause behavioral changes (or
behavioral harassment) by the bowhead whales. However, for the proposed
shallow hazard and site clearance surveys, the source levels of the
airgun array and other acoustic equipment are relatively low (about 214
dB re 1 microPa for the GeoChirp II, the loudest acoustic equipment
planed to be used), and that the modeled distance to the 160-dB
isopleths is estimated at 1,665 m (5,463 ft). Please see Number of
Marine Mammals Estimated to be Taken section below for a detailed
description of the calculation.
As far as mitigation measures are concerned, NMFS expects that the
distance from the source to the safety zone for cetaceans is
approximately 115 m (377 ft), where the received level is at 180 dB re
1 microPa, which is a small enough area to be effectively monitored by
NMFS-approved marine mammal monitors (MMOs). Furthermore, no seismic
surveys, ramp up included, will commence if there is a marine mammal
within the safety zone.
Comment 28: Citing the 90-day monitoring report for the SOI 2007
open water seismic activities, the NVPH is concerned that the shallow
hazard and site clearance surveys could exclude nearly all migrating
bowhead whales from waters within 20 km or more of the survey vessel,
since the 120-dB isopleth extends over 25 km. The NVPH states that
similar displacement of beluga whales at a large distance is also
possible.
Response: NMFS does not agree with NVPH's assessment regarding the
potential acoustic impacts to bowhead and beluga whales. First, as
discussed in Response to Comment 4, although it is possible that marine
mammals could react to any sound levels detectable above the ambient
noise level within the animals' respective frequency response range,
this does not mean that such animals are taken by Level B harassment
(see definition of Level B harassment above). The degree of reaction
which constitutes a ``take,'' i.e., a reaction deemed to be
biologically significant that could potentially disrupt the migration,
breathing, nursing, breeding, feeding, or sheltering, etc. of a marine
mammal is complex and context specific, and it depends on several
variables in addition to the received level of the sound by the
animals. In many cases, bowhead or beluga whales that are exposed to
120 dB re 1 microPa or higher do not exhibit noticeable behavioral
changes (e.g., Malme et al., 1984; Richardson et al., 1986; 1999;
Miller et al., 2005). Second, although migrating bowhead whales have
been seen to be excluded from entering areas with seismic sound levels
at approximately 120 dB re 1 microPa in the Beaufort Sea (Richardson et
al., 1999), NMFS believes this was due to the narrower migratory route
in the Beaufort Sea where the whales migration was impeded due to the
seismic noise. However, the migratory route of bowhead whales is much
wider in the Chukchi Sea. The wider migratory route allows bowhead
whales to go around the ensonified zone during their migration, instead
of being impeded by the sound. In addition, since the source levels
from the shallow hazard and site clearance survey are relatively low
(214 dB re 1 microPa for the source of the loudest acoustic equipment),
the ensonified zone would also be relatively small. If any deflection
were to occur, NMFS does not believe it would be biologically
significant. Therefore, NMFS does not believe that bowhead and beluga
whales would be displaced when exposed to received level from seismic
airguns at 120 dB re 1 microPa.
Comment 29: The NSB states CPAI used the density information to
estimate the number of belugas they may encounter and take during the
seismic operations, based on 2006 and 2007 vessel based survey, was not
appropriate, since these data were collected in the same season when
seismic operations were occurring and belugas appear to be sensitive to
industrial sounds. The NSB recommends that the Brueggerman et al.
(1990; 1991; 1992) observations be used to calculate the beluga
density. The NSB further states that if CPAI conducts surveys into
October or November, it would also encounter belugas from the Beaufort
Sea stock as the animals are migrating toward wintering areas.
Therefore, it is highly unlikely that only 10 belugas would be
disturbed.
Response: NMFS agrees with the NSB's assessment regarding the
uncertainty of beluga density in the vicinity of the proposed seismic
operation area. Although density estimate data for marine mammals in
the Arctic Ocean are available, NMFS typically uses the most recent
data because they are deemed to be reliable. In this case, the 2006 and
2007 beluga whale monitoring data provide the most recent scientific
information on the distribution of these animals, while the Brueggerman
et al. (1990; 1991; 1992) data are 16-18 years old. In addition, the
NSB did not provide the full citation of the Brueggerman et al.
references for NMFS to verify and compare. However, NMFS also
recognizes that satellite tagging efforts directed at the eastern
Chukchi stock of beluga whales showed that whales tagged in the eastern
Chukchi in summer traveled 1,100 km (684 mi) north of the Alaska
coastline and to the Canadian Beaufort Sea within 3 months of tagging
(Suydam et al., 2001), indicating significant stock overlap with the
Beaufort Sea stock of beluga whales. For these reasons, NMFS could not
provide a take estimate for beluga whales for both populations.
Nevertheless, recent data from the LGL Report (LGL, 2008), which was
based on marine mammal monitoring during the 2007 Shell and CPAI
seismic surveys, showed that beluga whale distribution in the proposed
seismic area in the Chukchi Sea is very low. Therefore, NMFS believes
that only a small undetermined number of beluga whales would be
affected by Level B harassment as a result of the proposed CPAI shallow
hazard and site clearance surveys.
Subsistence Uses
Comment 30: NVPH questions whether NMFS's assessment of the impacts
to subsistence was based on the ``best available scientific evidence''
and whether NMFS has made any effort to discern whether seismic
surveying activities in the Chukchi Sea in 2006 or 2007 had an adverse
impact on the availability of any or all seal and whale species for
subsistence uses.
Response: In making its final determination of whether the proposed
shallow hazard and site clearance surveys would have unmitigable
impacts to subsistence use of marine mammal populations in the affected
area, NMFS relies upon the best available scientific information to
make its MMPA determinations. In this case, NMFS has reviewed the 90-
day marine mammal monitoring and mitigation reports for the 2006 and
2007 open water seismic survey and shallow hazard and site clearance
survey conducted by Shell Offshore, Inc. (SOI), ConocoPhillips Alaska,
Inc., and GXTechnology in 2006 and by SOI in 2007 (Ireland et al.,
2007a; 2007b; Patterson et al., 2007; Funk et al., 2007; 2008). These
monitoring reports point out that the impacts to marine mammals as a
result of the 2006 and 2007 Arctic seismic activities were negligible.
In addition, actual take of marine mammals by Level B harassment was
generally lower than expected due to the implementation of monitoring
and mitigation measures. No marine
[[Page 49431]]
mammals were observed to have suffered injuries or death as a result of
the seismic surveys and none were suspected. In addition, information
presented by the oil and gas industry and independent researchers who
conducted marine mammal monitoring at the 2007 and 2008 Arctic Open
Water Scientific Meetings was also taken into consideration.
Comment 31: NVPH states that NMFS failed to provide the substantive
analysis to support any meaningful finding regarding the possible
effect of CPAI's activities on the availability of beluga whales,
seals, and bowhead whales for subsistence uses by coastal communities
along the Chukchi Sea or the effectiveness of mitigation measures to
eliminate such impacts. The NVPH further states that the Chukchi Sea
and the adjoining coast existed as a relatively pristine ocean
environment, free of industrial operations that would disturb bowhead
and beluga whales and seals with their availability for subsistence
uses. Therefore, NVPH states that even a slight interference in the
availability of these species to communities on the Chukchi Sea would
constitute an unmitigable adverse impact to their overall availability
for subsistence uses.
Response: NMFS does not agree with NVPH's statement. The FR Notice
of Proposed IHA provided a detailed analysis regarding the possible
effect of seismic surveys and underwater sound on marine mammals in the
planned action area. This analysis prompted NMFS to make a
preliminarily determination that the impact of conducting the shallow
hazard and site clearance surveys in Chukchi Sea may result, at worst,
in a temporary modification in behavior of small numbers of marine
mammals.
NMFS agrees that the Chukchi Sea and the adjoining coast existed as
a relatively pristine ocean environment that was free of industrial
operations. However, NMFS does not agree with NVPH's assessment that
within this environment, a slight interference in the availability of
these species to communities on the Chukchi Sea would constitute an
unmitigable adverse impact for subsistence uses of these species. The
proposed shallow hazard and site clearance surveys proposed by CPAI
would only occur in a small area within the much larger Chukchi Sea
basin for a brief period of 30-45 days. It would also occur far
offshore, approximately 70 miles, outside the area in which harvest
traditionally occurs. In addition, because CPAI's seismic surveys will
occur during the late summer and fall (after many of the Chukchi Sea
communities have harvested sizeable portions of their marine mammal
quota), NMFS does not believe that CPAI's activities are likely to
reduce the availability of the affected species to a level insufficient
for a harvest to meet its needs. NMFS does not expect subsistence users
to be directly displaced by the seismic surveys because subsistence
users typically do not travel this far offshore to harvest marine
mammals. Next, because of the significant distance offshore and the
lack of hunting in these areas, there is no expectation that any
physical barriers would exist between marine mammals and subsistence
users. Furthermore, mitigation and monitoring measures required for the
seismic activities are expected to reduce all potential impacts to
negligible levels to marine mammals and their habitat. Finally, CPAI
will be working with Native communities in the affected region to
ensure that seismic operations do not result in an unmitigable adverse
impact on the availability of marine mammals to subsistence uses by the
Native communities in and around the Chukchi Sea.
Comment 32: The CBD, NVPH, ICAS, and NSB state that the MMPA
requires that any incidental take authorized will not have ``an
unmitigable adverse impact on the availability of such species or stock
for taking for subsistence uses'' by Alaska Natives. The NVPH is
concerned that CPAI intends to conduct surveys within just a few miles
of the village of Wainwright, and that it also plans to conduct surveys
near the north end of Kasegaluk Lagoon, which is an important
subsistence use area for residents of Point Lay, and contains the
largest concentration of spotted seals in Alaska. The NSB is also
concerned about impacts to subsistence hunts of marine mammals in the
summer: notably beluga hunts at Point Lay and Wainwright, and walrus
and bearded seal hunts in all of the villages of the Alaska Bering and
Chukchi Seas. The NSB states that the summer beluga whale hunt at Point
Lay extends into July, the hunt in Wainwright extends into August, and
Point Hope and Wainwright hunt bowhead whales in the fall and these
hunts may be adversely affected. Additionally, CBD notes they are aware
that the NVPH, a federally recognized tribal government, has submitted
comments opposing the proposed take authorizations due to impacts on
subsistence, and along with many community members has commented on
myriad other related agency documents that have direct bearing on these
take authorization such as the Chukchi Sea Sale 193, MMS Five-Year
Plan, and the DPEIS. Similarly, the NSB, the AEWC, and REDOIL have all
filed challenges in federal court and/or the IBLA challenging offshore
activities due to impacts on the subsistence hunt of bowheads and other
species. In light of the positions of these communities and
organizations, the CBD does not think that NMFS can lawfully make the
findings required under the MMPA for approving CPAI's proposed IHA.
Response: NMFS does not agree with CBD, NVPH, ICAS, and NSB's
statement. The CPAI's shallow hazard and site clearance survey will not
occur in the coast of the Alaska North Slope. As stated in the FR
Notice of Proposed IHA, the two areas for the proposed CPAI shallow
hazard and site clearance surveys would be conducted about 111 km (69
mi) off the Alaska coast, generally west from the village of
Wainwright. Therefore, NVPH's concern that the proposed seismic
activities would be conducted just miles off the coast is unwarranted.
Although CPAI plans to conduct its shallow hazard and site
clearance survey in August, it is likely that the surveys would not
start until mid-August, thus missing the summer beluga hunt at Point
Lay and most in Wainwright. In addition, as mentioned earlier, the
proposed shallow hazard and site clearance survey would be conducted 69
miles off the coast and would therefore not overlap with the
subsistence harvest of beluga whales and bearded seals. The subsistence
hunt of walruses was reviewed by the FWS since it is a species under
the FWS jurisdiction. An LOA was issued by the FWS for the take of
walruses incidental to CPAI's proposed seismic surveys. Finally, the
IHA issued to CPAI includes specific mitigation measures that would
prevent any unmitigable impacts to subsistence use of marine mammals
from the proposed seismic activities. Please refer to the Mitigation
Section of this document for detailed information.
Comment 33: The AEWC states that CPAI has not communicated its
intentions regarding the signing of Conflict Avoidance Agreement (CAA)
with the AEWC, and that it understands that CPAI would not agree to the
2008 CAA. Therefore, AEWC observes that to issue an IHA to a company
that would not voluntarily agree to the terms of the CAA, NMFS must
limit its authorization to times and locations that would ensure they
company's compliance with the mitigation measures set forth in the
CAA--no more than two simultaneous geophysical activities in each of
the Beaufort and Chukchi Seas. The AEWC
[[Page 49432]]
further states that it would not oppose an IHA issued to CPAI
containing these limitations and the other requirements and
recommendations provided by the NSB in its comments. Finally, the AEWC
states that it will oppose any IHA issued by NMFS that does not contain
mitigation measures identical to those set forth in the 2008 CAA.
Response: Comment noted. Under sections 101(a)(5)(A) and (D) of the
MMPA (16 U.S.C. 1361 et seq.), an IHA or LOA would be granted to U.S.
citizens who engage in a specified activity (other than commercial
fishing) within a specified geographical region if NMFS finds that the
taking of marine mammals will have a negligible impact on the species
or stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for certain subsistence uses,
and if the permissible methods of taking and requirements pertaining to
the mitigation, monitoring and reporting of such takings are set forth.
In other words, no marine mammal take authorizations may be issued if
NMFS has reason to believe that the proposed exploration or development
activities would not have an unmitigable adverse impact on the
availability of marine mammal species or stock(s) for Alaskan native
subsistence uses. Although Federal laws do not require consultation
with the native coastal communities until after offshore exploration
and development plans have been finalized, permitted, and authorized,
pre-permitting consultations between the oil and gas industry and the
Alaskan coastal native communities are considered by NMFS when the
agency makes a determination whether such activities would have an
unmitigable adverse impact on the availability of marine mammal species
or stock(s) for subsistence uses. For the proposed shallow hazard and
site clearance survey, CPAI has conducted POC meetings for its seismic
operations in the Chukchi Sea in the communities and villages of
Kivalina, Kotzebue, Wainwright, Barrow, Point Lay, and Point Hope.
CPAI has not signed the 2008 CAA with Alaska Natives and has
informed NMFS that it does not intend to do so. NMFS has scrutinized
all of the documents submitted by CPAI (e.g., IHA application, Plan of
Cooperation and other correspondence to NMFS and affected stakeholders)
and documents submitted by other affected stakeholders and concluded
that harassment of marine mammals incidental to CPAI's activities will
not have an unmitigable adverse impact on the availability of marine
mammals for taking for subsistence uses. This finding was based in
large part on NMFS' definition of ``unmitigable adverse impact'', the
proposed mitigation and monitoring measures, the 2008 CAA signed by
other industry participants and Alaska Natives, the scope of activities
proposed to be conducted, including time of year, location and presence
of marine mammals in the project area, and CPAI's Plan of Cooperation.
As described in CPAI's IHA application, the seismic survey is
proposed to be conducted approximately 70 miles off the Alaskan coast
in the Chukchi Sea where very little subsistence harvest occurs. In
addition, because CPAI's seismic surveys will occur during the late
summer and fall (after many of the Chukchi Sea communities have
harvested sizeable portions of their marine mammal quota), NMFS does
not believe that CPAI's activities are likely to reduce the
availability of the affected species to a level insufficient for a
harvest to meet its needs. NMFS does not expect subsistence users to be
directly displaced by the seismic surveys because subsistence users
typically do not travel this far offshore to harvest marine mammals.
Next, because of the significant distance offshore and the lack of
hunting in these areas, there is no expectation that any physical
barriers would exist between marine mammals and subsistence users. For
bowhead whale subsistence hunting, recent history shows that Point Hope
and Wainwright only hunt during the spring migration (Suydam et al.,
2005; Suydam and George, 2004). The village of Barrow hunts during the
spring and fall migrations, taking most bowheads during the spring
migration. The fall hunt occurs in open water from late August through
October by Barrow, and whalers hunt mainly in the waters east and
northeast of Point Barrow in the Beaufort Sea. Also, hunters prefer to
take bowheads close to shore to avoid a long tow during which the meat
can spoil. Beluga whales are hunted for subsistence at Barrow,
Wainwright, Point Lay, and Point Hope, with the most taken by Point Lay
(Fuller and George, 1997). Harvest at all of these villages generally
occurs between April and July with most taken in April and May when
pack-ice conditions deteriorate and leads open-up. Ringed, bearded, and
spotted seals are hunted by all of the villages bordering the project
area (Fuller and George, 1997). Ringed and bearded seals are hunted
throughout the year, but most are taken in May, June, and July when ice
breaks up and there is open water instead of the more difficult hunting
of seals at holes and lairs. Spotted seals are only hunted in spring
through summer. Therefore, the scheduling of the proposed shallow
hazard and site clearance survey is expected to have minimum conflict
between the industries and marine mammal harvests.
Finally, in the event harvest activities do occur this far
offshore, the required mitigation and monitoring measures are expected
to reduce any adverse impacts on marine mammals for taking for
subsistence uses to the extent practicable. These measures include, but
are not limited to, the 180 dB and 190 dB safety (shut-down/power-down)
zones; a requirement to monitor the 160 dB isopleths for aggregations
of 12 or more non-migratory balaenidae whales and when necessary shut-
down seismic airguns; maintaining a distance of at least 15 miles from
other operating seismic vessels; reducing vessel speed when a vessel is
within 300 yards of whales to avoid a collision; utilizing
communication centers to avoid any conflict with subsistence hunting
activities; and the use of marine mammal observers. Many of these
requirements are consistent with the measures contained in the 2008 CAA
entered into between other industry participants who operate in the
Chukchi Sea and Alaska Natives.
NMFS does not agree with AEWC's recommendation to limit no more
than two simultaneous geophysical activities in each of the Beaufort
and Chukchi Seas. As analyzed in detail in the MMS 2006 PEA and NMFS
2008 SEA, a total of four simultaneous geographical/seismic activities
can be conducted in each of the Beaufort and Chukchi Seas without
significant impacts to the human environment. A similar finding was
made for the proposed 2008 CPAI shallow hazard and site clearance
survey in the Chukchi Sea.
Comment 34: NVPH states that it noted that CPAI proposes to
mitigate impacts to subsistence activities via measures developed
through a Plan of Cooperation (POC) with the AEWC and a variety of
meetings and consultations. The NVPH states that there is no guarantee
that these processes would result in enforceable limits that ensure
CPAI's activities have no unmitigable adverse impact on the
availability of seals and whales for subsistence purposes. The NVPH
further states that by relying on these processes without ensuring that
they produce a meaningful outcome, NMFS has effectively deferred its
determination whether CPAI's activities would have an unmitigable
adverse impact on the availability of
[[Page 49433]]
seals and whales for subsistence uses by communities along the Beaufort
Sea until after a POC has been developed.
Response: NMFS does not agree with NVPH's assessment. First, the
proposed CPAI shallow hazard and site clearance survey is planned in
the Chukchi Sea, not the Beaufort Sea as NVPH stated in its comment. In
order to make a determination that the proposed CPAI 2008 shallow
hazard and site clearance surveys would not have a unmitigable adverse
impact on the availability of marine mammal species or stocks for
taking for subsistence uses in the proposed seismic area, NMFS
carefully reviewed and analyzed the proposed seismic activities before
making its determination (see Response to Comment 33). NMFS also
reviewed other information presented in various documents, including
but not limited to, the MMS 2006 PEA, the MMS 2007 draft PEIS, 2006 and
2007 Arctic seismic survey monitoring reports, and the 2008 CAA.
Comment 35: NVPH states that NMFS failed to discuss a mandatory
limit on the number of concurrent seismic and/or shallow hazard surveys
in the Chukchi Sea. NVPH requests NMFS to prohibit the simultaneous
operation of multiple vessels within the Chukchi Sea during the fall
bowhead migration. NVPH further requests that NMFS require that no two
vessels operate within 100 km (62 mi) of one another, because given the
large size of the 120 dB zone, closer simultaneous operation would pose
a real risk of disrupting the bowhead whale migration.
Response: NMFS does not agree with NVPH's statement and request.
First, the MMS 2006 PEA, which NMFS incorporated into its 2008 SEA,
provided a thorough analysis on the maximum number of eight seismic
activities that could occur in the Chukchi and Beaufort Seas. The
analysis lead NMFS and MMS to conclude that up to a maximum of eight
seismic surveys would not result in significant impacts to the quality
of the human environment. In addition, NMFS' 2008 SEA, which analyzed
the effect of multiple seismic surveys also lead NMFS to conclude that
the CPAI survey would not result in a significant impacts.
NVPH has not provided NMFS with any data to support its argument
that multiple seismic vessels should not be permitted in the Chukchi
Sea or that no more than 2 vessels be allowed to operate within 100 km
(62 mi) of one another. The 100 km (62 mi) separating distance for the
120 dB zone between vessels is not scientifically supportable. The
distance where the received level reaches 120 dB re 1 microPa is
dependent upon the source level and oceanographic conditions. For the
same oceanographic conditions, the higher the source level, the longer
the distance where the received level would reach 120 dB. Therefore, at
this time, there is no basis upon which to limit effort to no more than
2 vessels within 100 km of one another.
Mitigation and Monitoring
Comment 36: Dr. Bain questions the effectiveness of marine mammal
monitoring with only two MMOs on duty full time. Citing Forney and
Barlow (1998) and Dahlheim and Towell (1994), Dr. Bain states that a
common work schedule where consistent effort is required would be 40
minutes on, 40 minutes off, 40 minutes on, two hours off, three times a
day. Dr. Bain suggests that an observation team of 12 MMOs would be
required to cover a 24-hour period. Dr. Bain further states that the
probability of detecting marine mammals would drop with increased
distance from the vessel.
Response: NMFS does not agree with Dr. Bain's assessment and
suggestions regarding MMOs and marine mammal monitoring. NMFS reviewed
the references (Dahlheim and Towell, 1994; Forney and Barlow, 1998)
provided by Dr. Bain, and did not find any type of work schedules
described. Unlike observers during marine mammal population surveys who
are required to search the entire field for any marine mammals, the
primary responsibility for MMOs is to monitor the safety zones, which
in this case are 115 m (377 ft) radius for the 180-dB isopleth and 20 m
(66 ft) radius for the 190-dB isopleth, and to ensure that proper
mitigation measures (power-down or shut-down acoustic sources) are
implemented if a marine mammal enters or is sighted within these safety
zones. NMFS agrees that the detection probability of a marine mammal
drops with increased distance from the ship. However, the occurrence of
marine mammals outside the safety zones is not a big concern for marine
mammal monitoring during the proposed seismic activity because it is
presumed these animals would not be within a zone that could result in
injury. Furthermore, MMOs would be on duty for 4 consecutive hours or
less to reduce fatigue. In addition, all MMOs hired for the proposed
seismic surveys must be NMFS-approved observers who are qualified to
perform the required monitoring tasks. Therefore, NMFS believes that
two MMOs are effective for marine mammal monitoring for CPAI's shallow
hazard and site clearance surveys.
Comment 37: Dr. Bain is concerned that many species that are
capable of diving for more than 30 minutes could be missed during the
monitoring.
Response: NMFS agrees with Dr. Bain that monitoring for deep diving
marine mammals it poses a challenge. However, within the proposed
seismic survey area, there are no marine mammals that normally dive for
more than 30 minutes. However, in the event that a marine would be
missed during the initial pre-survey monitoring, ramp-up procedures
will be followed when an acoustic source begins to operate, so the
undetected animal(s) would have an opportunity to detect the sound as
it increases gradually and move away from the source. Please refer to
Monitoring and Mitigation Measures section below for a detailed
description of these measures.
Comment 38: NVPH is concerned that NMFS did not discuss the option
of requiring CPAI to power down its airguns and other sound sources
when aggregations of feeding, resting or socializing bowhead whales or
gray whales are located within the 160 dB isopleth, and that NMFS fails
to discuss the option of requiring CPAI to monitor the 120 dB isopleth
for bowhead cow-calf pairs and to require CPAI to power down its sound
sources when four or more cow-calf pairs are observed to be exposed to
noises at or above 120 dB. NVPH requests that NMFS requires both of
these mitigation measures. Citing Richardson's observation, NVPH
further states that nearly all bowhead whales avoid seismic airguns at
received levels as low as 107 dB, and requests NMFS to impose a safety
zone for bowhead cow-calf pairs exposed to 107 dB or more. In addition,
as NVPH observes that it would be impossible to monitor such a large
area be ship-based observation, NVPH requests that such monitoring be
conducted by aerial observation together with ship-based observers, for
both of these safety zones.
Response: In its final determination and the IHA issued to CPAI,
NMFS requires CPAI to establish a 160-dB safety zone whenever an
aggregation of 12 or more bowhead whales or gray whales are observed.
If an aggregation of 12 or more bowhead or gray whales is observed
within the 160-dB safety zone around the seismic activity, the seismic
operation will not commence, or will shut down, until two consecutive
vessel surveys indicate they are no longer present within the 160-dB
safety zone of seismic-surveying operations.
However, NMFS will not impose a requirement to conduct aerial
monitoring of the 120-dB safety zone for the occurrence of four or more
cow-calf
[[Page 49434]]
pairs in the Chukchi Sea because it is not practicable. First, the 120-
dB safety zone would require a safety zone of 20 km (12 mi) in radius,
which is beyond the range for visual monitoring. The 120-dB ensonified
zone is also too large to be monitored by chase boats. Second, aerial
surveys are not required in the Chukchi Sea because they have currently
been determined to be impracticable due to lack of adequate landing
facilities, the prevalence of fog and other inclement weather in that
area, thereby resulting in safety concerns.
As far as the NVPH's statement that nearly all bowhead whales avoid
seismic airguns at received levels as low as 107 dB, NMFS is not able
verify NVPH's assessment because NVPH did not provide a reference to
support its statement. A comprehensive review by Southall et al. (2007)
on the potential acoustic impacts to low-frequency cetaceans (bowhead
and other large whales) does not list any reference that shows these
animals react to received levels under 110 dB re 1 microPa. Therefore,
NMFS does not believe bowhead whales exposed to 107 dB would be taken
by Level B behavioral harassment, and that imposing a safety zone of
107 dB is not appropriate.
Comment 39: CPAI states that they are not able to ramp up the
single source because they plan to use a low level sparker seismic tool
for the geohazard surveys. CPAI requests that NMFS not require ramp-up
procedures. CPAI indicates that they would still follow the following
mitigation measures, including (1) vessel speed or course alteration;
(2) shutdown procedures; (3) MMOs on the vessels; and (4) communication
systems to stay in contact with villages and hunters to avoid conflict
with subsistence activities.
Response: With respect to CPAI's comment, NMFS has communicated
with ASRC Energy Services (AES), which plans to conduct a similar
shallow hazard and site clearance survey in the Chukchi Sea during the
2008 open water season and use essentially the same acoustic equipment
CPAI listed in its IHA application. AES indicated that all of these
Sparker acoustic systems can be ramped up. NMFS has also been informed
by the U.S. Geological Survey and other contractors who use Sparker or
similar acoustic systems that these acoustic devices have the
capability to ramp up. Based upon this information and the technology
identified in CPAI's application, there does not appear to be a
legitimate reason for waiving the ramp up procedures because Sparker or
similar acoustic systems are capable of ramp up and these devices are
available for CPAI's use this season. In addition, ramping up is a
standard mitigation measure for seismic surveys that introduce high
level acoustic energy (over 200 dB re 1 microPa) into the water column,
and is described in the MMS 2006 PEA, the MMS 2007 draft PEIS, and NMFS
2008 SEA for seismic surveys in the Arctic as a required mitigation
measure under the preferred alternative. Furthermore, NMFS requires all
IHA applicants that plan to conduct seismic surveys in the 2008 Arctic
open-water season to ramp up their seismic sources as a mitigation
measure. Therefore, NMFS cannot waive ramp-up requirement just for
CPAI.
After further discussion with CPAI, CPAI agreed that they will use
a smaller sparker tool to initiate the survey and then transfer to the
larger sparker. This process would be equivalent to a traditional ramp
up requirement and would be an appropriate mitigation measure.
Comment 40: NVPH states that NMFS failed to provide for peer review
of CPAI's proposed monitoring plans. It further states that the
presentation provided by CPAI at the 2008 Open Water Scientific Meeting
only gave very limited information and was unable to respond to even
the most basic questions raised by attendees. NVPH requests NMFS to
reject any suggestion that the meeting satisfied the peer review
requirement. NVPH states that peer review by independent, objective
reviewers remains necessary.
Response: In order for the independent peer-review of Arctic area
activity monitoring plans, it must be conducted in an open and timely
process. Review by organizations, such as the National Academy of
Sciences, would take at least a year to complete and would likely
provide for an inflexible monitoring plan (e.g., any modifications
would require reconvening the Committee). As a result, NMFS believes
that independent peer-review of monitoring plans can be conducted via
two means. First, the monitoring plans are made public and available
for review by scientists and members of the public in addition to
scientists from the NSB, NMFS, and the FWS. In accordance with the
MMPA, the Marine Mammal Commission's Committee of Scientific Advisors
reviews all IHA applications, including the monitoring plans. Second,
monitoring plans and the results of previous monitoring measures are
reviewed once or twice annually at public meetings held with the
industry, the AEWC, the NSB, Federal agencies and the public. CPAI's
mitigation and monitoring plan was reviewed by scientists and
stakeholders at a meeting in Anchorage between April 14, 2008, and
April 16, 2008, and by the public between May 23, 2008 (73 FR 30064)
and June 23, 2008. NMFS believes that it has met the requirements of
section 101(a)(5)(D) of the MMPA.
Comment 41: The CBD, NSB, ICAS, and Dr. Bain state that during
night-time and poor visibility condition, CPAI proposes essentially no
limitations on operations, even though the likelihood of observers
seeing marine mammals in such conditions is very low. The NSB requests
NMFS to require CPAI to cese operations during darkness and inclement
weather until another technique becomes available for observing safety
zones under such conditions. The NSB further states that MMOs would not
be able to measure Level B impacts because they would not be able to
see far enough away from the vessel to observe the zones where Level B
takes may occur.
Response: The IHA issued to CPAI does not allow the start up of
acoustic sources when the entire safety zones cannot be adequately
monitored. However, as stated in the FR Notice of Proposed IHA, once
the safety zones are visually established and that pre-survey
monitoring has determined there are no marine mammals within the safety
zones, seismic surveys can commence and continue into low visibility
conditions. However, if for any reason the seismic sources are stopped
during low visibility conditions, they are not to be restarted until
the conditions are suitable for the marine mammal visual monitoring so
that the safety zones can be reestablished. Nevertheless, ramping up of
airguns and other seismic equipment during under normal visual
conditions is expected to keep marine mammals from entering the
established safety zones. In addition, NMFS also does not agree with
NSB's assessment that the MMOs are not able to monitor the entire Level
B zone. The 160-dB isopleth is estimated to be 1,665 m, which can
reasonably be monitored from the source vessel with binoculars. Please
refer to Monitoring and Mitigation Measures section below for a
detailed description.
Comment 42: The CBD and NSB state that NMFS and CPAI did not
adequately consider the use of passive acoustic monitoring (PAM). While
past IHAs have required PAM, this IHA completely ignores even
discussing the possibility of using such monitoring.
Response: NMFS disagrees. The MMPA has not established standards
for
[[Page 49435]]
monitoring requirements. The monitoring requirements proposed are to
ensure that the taking will have a negligible impact on the species or
stock(s) and will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses.
Monitoring measures are also used to reduce the level of takes to the
lowest level practicable due to implementation of the mitigation
measures.
Monitoring measures for different projects are proposed on a case-
by-case basis, and there is no ``one size fits all'' type of monitoring
protocol. For the proposed shallow hazard and site clearance survey in
the Chukchi Sea, the radius of the safety zone (115 m, or 377 ft) based
on the 180 db re: 1 microPa isopleth is too small to allow accurate and
effective passive acoustic monitoring. As the Joint Nature Conservation
Committee (JNCC, 2004) stated that in practice the exclusion zone
(safety zone) needs to be more than 500 m (1,640 ft) to allow for
accurate passive acoustic monitoring (PAM). JNCC also noted that in
many cases PAM is not as accurate as visual observation when
determining range. NMFS believes that in the subject seismic survey
projects, where the safety zone is as small as 115 m (377 ft), passive
acoustic monitoring is not warranted. The presence of additional
vessels for deploying PAM would only introduce more noise to the small
area where the proposed projects are to occur.
NEPA
Comment 43: NVPH, CBD, ICAS, and the NSB state that NMFS must
prepare an Environmental Impact Statement (EIS) to evaluate CPAI's
shallow hazard surveys, together with the other seismic and shallow
hazard surveying activity proposed for the summer of 2008 in the
Beaufort and Chukchi Seas.
Response: NMFS prepared a Final SEA to analyze further the effects
of CPAI's (and other companies) proposed open-water shallow hazard and
site clearance survey activities for the 2008 season. NMFS has
incorporated by reference the analyses contained in MMS 2006 Final PEA
for Arctic OCS Seismic Surveys in the Beaufort and Chukchi Seas and has
also relied in part on analyses contained in the MMS 2007 FEIS for the
Chukchi Sea Lease Sale 193, the MMS 2003 FEIS for multiple lease sales,
and the MMS 2007 DPEIS submitted for public comment on March 30, 2007.
The 2006 PEA analyzed a broad scope of proposed seismic activities
in the Arctic Ocean. In fact, the PEA assessed the effects of multiple,
ongoing seismic surveys (up to 8 surveys) in the Beaufort and Chukchi
Seas for the Arctic open water season. Although CPAI's proposed
activity for this season was not explicitly identified in the 2006 PEA,
the PEA did contemplate that future seismic activity, such as CPAI's
could occur. NMFS believes the range of alternatives and environmental
effects considered in the MMS 2006 PEA, combined with NMFS' SEA for the
2008 season are sufficient to meet the agency's NEPA responsibilities.
In addition, the 2008 SEA includes new information obtained since the
2006 Final PEA was issued, including updated information on cumulative
impacts. NMFS also includes a new section in the 2008 SEA, which
provides a review of the 2006 and 2007 monitoring reports. As a result
of our review and analysis, NMFS has determined that it was not
necessary to prepare and issue an EIS for the issuance of an IHA to
CPAI in 2008 for seismic activity in the Chukchi Sea but that
preparation of an SEA and issuance of a Finding of No Significant
Impact (FONSI) were sufficient under NEPA.
Comment 44: The NSB, NVPH, ICAS, and CBD state that NMFS appears to
rely on the NEPA analysis in the DPEIS in clear violation of NEPA law.
They state that NEPA requires agencies to prepare a draft EIS, consider
public and other agency comments, respond to these comments in its
final EIS, and wait 60 days before issuing a final decision. The CBD
further states that before the record of decision has been issued on
the final PEIS, NMFS cannot authorize CPAI's proposed seismic surveys
because the purpose of the PEIS process is to consider seismic surveys
in the Chukchi and Beaufort Seas for the years 2008 and beyond. The CBD
states that NMFS seems to either be relying on a NEPA document that is
not just inadequate, but which by its very terms only covers activities
from two years ago (the 2006 PEA), or one which is nowhere near
complete (the 2007 DPEIS).
Response: See Response to Comment 43 on this concern. Contrary to
the NSB's and CBD's statement, NMFS relied on information contained in
the MMS 2006 Final PEA, as updated by NMFS' 2008 SEA for making its
determinations under NEPA and that the DPEIS was not the underlying
document to support NMFS' issuance of CPAI's IHA. NMFS merely relied
upon specific pieces of information and analyses contained in the DPEIS
to assist in preparing the SEA. It is NMFS' intention that the PEIS
currently being developed will be used to support, in whole, or in
part, future MMPA actions relating to oil and gas exploration (i.e.,
seismic surveys) in the Arctic Ocean. Additionally, NMFS believes that
a SEA is the appropriate NEPA analysis for this season as the amount of
activity for 2008 is less than what was analyzed in the 2006 PEA.
Comment 45: NVPH states that the MMS 2006 PEA is flawed since it
understates the risk of significant impacts to bowhead whales, and
therefore, it is inappropriate for NMFS to rely on that document. NVPH
states that the 2006 PEA assumed the source vessels would ensonify much
smaller zones than those which have been subsequently measured in the
field. NVPH states that based on the propagation actually measured in
2006 and 2007, the impacts of a single 3D seismic survey are two to
three times as large as NMFS anticipated or more. The impacts of a
single shallow hazard survey are comparable to the impacts NMFS
anticipated from a single 2D or 3D seismic survey. Before authorizing
further seismic surveying activity or shallow hazard surveys in the
Arctic Ocean, NVPH requests NMFS to complete the PEIS that it began in
2006 to evaluate the potentially significant impacts of such
activities.
Response: NMFS does not agree with NVPH's statement. First, the
subject 2006 PEA was written by MMS, not NMFS. However, NMFS was a
cooperating agency under NEPA in its preparation. Second, as noted in
your cited part in the 2006 PEA, 20 km (12.4 mi) was used for
illustrative purposes in an exercise to estimate impact of 4 seismic
vessels operating within 24 km (15 mi) of each other. To do so, MMS
created a box (that was moveable along the Beaufort or Chukchi Sea
coast) to make these estimates. NMFS believes that the use of 20 km
(12.4 mi) remains the best information available at this time and was
the radius agreed to by participants at the 2001 Arctic Open-water
Noise Peer Review Workshop in Seattle, Washington. This estimate is
based on the results from the 1998 aerial survey (as supplemented by
data from earlier years) as reported in Miller et al. (1999). In 1998,
bowhead whales below the water surface at a distance of 20 km (12.4 mi)
from an airgun array received pulses of about 117-135 dB re 1 microPa
rms, depending upon propagation. Although NVPH states that propagation
actually measured in 2006 and 2007 showed that the impacts of a single
3D seismic survey are two to three times as large as NMFS anticipated,
NVPH failed to provide any data to support this statement. In fact, the
marine mammal monitoring reports for the 2006 and
[[Page 49436]]
2007 open water seismic surveys clearly showed that at 20 km (12.4 mi)
the received levels from large airgun arrays used in 3D seismic surveys
fall between 140 and 160 dB re 1 microPa (Ireland et al., 2007a; 2007b;
Patterson et al., 2007; Funk et al., 2007; 2008), which is below NMFS
current noise exposure standard for Level B behavioral harassment. For
this reason, until more data collection and analyses are conducted on
impacts of anthropogenic noise (principally from seismic) on marine
mammals in the Beaufort and Chukchi seas, NMFS will continue to use 20
km (12.4 mi) as the radius for estimating impacts on bowhead whales
during the fall migration period.
Comment 46: NVPH states that the MMS 2006 PEA fails to provide
site-specific analysis. Thus, in order to reduce the likelihood of
significant impacts, NMFS has imposed 160 dB and 120 dB safety zones
when authorizing surveys pursuant to the PEA. At a minimum, it must do
the same for CPAI's surveys but with the modifications to the safety
zones discussed above.
Response: NMFS does not agree with NVPH's statement. Although the
MMS 2006 PEA did not explicitly provide site-specific analysis on the
proposed CPAI shallow hazard and site clearance surveys, NMFS SEA
prepared for the 2008 open-water season described its specific location
and time of operation. As in the PEA, NMFS' 2008 SEA has described
additional mitigation measures such as imposing the 160 dB safety zone
for seismic activities in the Chukchi Sea when an aggregation of 12 or
more bowhead or gray whales is sighted. This mitigation measure is
required in the IHA issued to CPAI. Regarding imposing the 120-dB
safety zone, it would pose safety and practical concerns for marine
mammal monitoring in the Chukchi Sea. Therefore, a safety zone based on
received level of 120 dB re 1 microPa will not be imposed in the
Chukchi Sea as it has been determined to be impracticable under the
MMPA.
Comment 47: The NVPH and NSB state that the scope of the MMS 2006
PEA is explicitly limited to activities that occur during 2006, and
that those seismic survey activities have already occurred, as well as
an additional season worth of activities in 2007. NVPH states that the
PEA does not evaluate activities that will occur over a period of
several years, though NMFS has continued to rely on it as if its scope
were for a multi-year program of seismic surveys. In addition, NVPH
states that the PEA uses arbitrary significance criteria for non-
endangered marine mammals that would allow long-lasting impacts to
populations, or in fact the entire Arctic ecosystem, that would
nonetheless be deemed insignificant. NVPH states that these
significance criteria are inappropriate for an evaluation of impacts
from seismic surveys, as indicated by MMS' use of more defensible
significance criteria based on potential biological removal form marine
mammal populations affected by seismic surveys in the Gulf of Mexico.
Response: NMFS does not agree with the NVPH and NSB's statement, as
failed to provide any support for their position. The MMS 2006 PEA, in
which NMFS was a cooperating agency, provided a thorough description
and analysis on the affected environment, including ESA-listed and non-
ESA-listed species. Under the NEPA, there is no ``significance criteria
for non-endangered'' species. The criteria for determining whether a
proposed action would result in significant effects to the environment
are contained in CEQ's regulations. NVPH's statement that MMS' such
analysis ``would allow long-lasting impacts to populations, or in fact
the entire Arctic ecosystem, that would nonetheless be deemed
insignificant'' in a way supports the MMS 2006 PEA. In addition, NMFS
has prepared and released to the public an SEA for the proposed 2008
Arctic seismic surveys in the Chukchi and Beaufort Seas (see ADDRESSES
for availability). This SEA incorporates by reference the relevant
information contained in the 2006 PEA and updates that information
where necessary to assess impacts on the marine environment from the
2008 seismic survey activities. Further, the SEA and FONSI considered
the CEQ significance criteria (including the criteria developed by
NMFS) to determine whether take of marine mammals incidental to CPAI's
seismic survey would result in significant impacts to the human
environment. NMFS believes that the agency has complied with the
requirements of NEPA in its preparation of its NEPA documents.
Comment 48: Oceana and Ocean Conservancy are concerned that oil and
gas activities may have substantial negative effects on marine mammals
and other Arctic species. Oceana and Ocean Conservancy further state
that there has never been a comprehensive evaluation of the cumulative
effects of seismic activities in the Arctic. Oceana and Ocean
Conservancy request that in light of the dramatic effects of climate
change in the Arctic, NMFS must not approve further seismic activities
without such a comprehensive evaluation.
Response: NMFS shares Oceana and Ocean Conservancy's concern that
the increasing industrial activities, including oil and gas
development, could have profound negative effects on marine mammals in
the Arctic region. Nevertheless, NMFS believes that proactive efforts
to conserve and protect marine mammals and other Arctic species, such
as NMFS' initiation of status reviews of ice seals and the recent FWS'
ESA-listing of polar bears, combined with prudent natural resources
management and regulations on industrial activities by Federal Agencies
would reduce these adverse impacts to biologically non-significant or
negligible levels. In addition, monitoring and mitigation measures
required for certain industrial activities would further reduce and
minimize such negative effects to marine mammal species and stocks.
Long term research and monitoring results on ice seals in the Alaska's
North Slope have shown that effects of oil and gas development on local
distribution of seals and seal lairs are no more than slight, and are
small relative to the effects of natural environmental factors (Moulton
et al., 2005; Williams et al., 2006).
NMFS does not agree with Ocean and Ocean Conservancy's statement
that there has never been a comprehensive evaluation of the cumulative
effects of seismic activities in the Arctic. The MMS 2006 PEA, NMFS
2007 SEA, MMS 2007 draft PEIS, and NMFS 2008 SEA for the proposed
issuance of five seismic survey and shallow hazard and site clearance
survey activities for the 2008 open water season all provide
comprehensive evaluation of the cumulative effects of seismic
activities in the Arctic.
Comment 49: NSB and CBD are both concerned about cumulative impacts
from multiple operations. CPAI's proposal is only one of numerous oil
industry activities recently occurring, planned, or ongoing in the U.S.
portions of the Chukchi and Beaufort Seas (e.g., proposed IHA for on-
ice seismic surveys in Harrison Bay; proposed scientific seismic survey
by the National Science Foundation (NSF); NMFS' 5-year regulations for
activities related to Northstar; SOI IHA for Beaufort Sea exploratory
drilling; CPAI IHA for Beaufort Sea; SOI IHA for Beaufort Sea; two
proposed IHAs for Chukchi Sea and two proposed for the Beaufort Sea;
and FWS 5-year regulations for oil and gas activities in the Beaufort
Sea). No analysis of seismic surveys in the Russian or Canadian
portions of the Chukchi and Beaufort seas is mentioned
[[Page 49437]]
either. Similarly, significant increases in onshore oil and gas
development with attendant direct impacts and indirect impacts on
marine mammals such as through increased ship traffic are also
occurring and projected to occur at greater rates than in the past. CBD
states that further cumulative effects impacting the marine mammals of
the Beaufort and Chukchi Seas are outlined in their NEPA comments on
the MMS PEA and the DPEIS.
The NSB points out that in addition to the proposed offshore
industrial operations listed above, there will be supply and fuel
barging to villages, barging for support of onshore development and
exploration, scientific cruises, climate change studies, USCG
operations, tourist vessel traffic, and other activities as well. The
cumulative impacts of all these activities must be factored into any
negligible impact determination. Further, without an analysis of the
effects of all of the planned operations, it is impossible to determine
whether the monitoring plans are sufficient.
Response: Under section 101(a)(5)(D) of the MMPA, NMFS is required
to determine whether the taking by the applicant's specified activity
will have a negligible impact on the affected marine mammal species or
population stocks. Cumulative impact assessments are NMFS'
responsibility under NEPA, not the MMPA. In that regard, the MMS Final
PEA and NMFS SEA address cumulative impacts. The Final PEA's cumulative
activities scenario and cumulative impact analysis focused on oil and
gas-related and non-oil and gas-related noise-generating events/
activities in both Federal and State of Alaska waters that were likely
and foreseeable. Other appropriate factors, such as Arctic warming,
military activities, and noise contributions from community and
commercial activities were also considered. Appendix D of the Final PEA
addresses similar comments on cumulative impacts, including global
warming. That information was incorporated into and updated in the NMFS
2008 SEA and into this document by citation. NMFS adopted the MMS Final
PEA, and it is part of NMFS' Administrative Record. Finally, NMFS does
not require authorizations under section 101(a)(5) of the MMPA for
normal shipping or transit.
Comment 50: According to CBD, another factor causing NMFS'
``negligible impact'' findings to be suspect is the fact that the
Chukchi Sea area is undergoing rapid change as a result of global
warming. For species under NMFS' jurisdiction, and therefore subject to
the proposed IHA, seals are likely to face the most severe
consequences. The Arctic Climate Impact Assessment (ACIA) concluded
that ringed, spotted, and bearded seals would all be severely
negatively impacted by global warming this century. The ACIA stated
that ringed seals are particularly vulnerable: ``Ringed seals are
likely to be the most highly affected species of seal because all
aspects of their lives are tied to sea ice'' (ACIA, 2004). In 2003, the
NRC noted that oil and gas activities combined with global warming
presented a serious cumulative impact to the species: ``Climate warming
at predicted rates in the Beaufort Sea region is likely to have serious
consequences for ringed seals and polar bears, and those effects will
accumulate with the effects of oil and gas activities in the region.''
NMFS' failure to address global warming as a cumulative effect renders
its negligible impact findings invalid.
Response: Under section 101(a)(5)(D) of the MMPA, ``the Secretary
shall authorize... taking by harassment of small numbers of marine
mammals of a species or population stock by such citizens while
engaging in that activity within that region if the Secretary finds
that such harassment during each period concerned (I) will have a
negligible impact on such species or stock, and (II) will not have an
unmitigable adverse impact on the availability of such species or stock
for taking for subsistence uses.'' Section 101(a)(5)(D) of the MMPA
does not require NMFS to base its negligible impact determination on
the possibility of cumulative effects of other actions.
As stated in previous responses, cumulative impact assessments are
NMFS' responsibility under NEPA, not the MMPA. In that regard, the MMS
2006 Final PEA and NMFS' 2008 SEA address cumulative impacts. The PEA's
cumulative activities scenario and cumulative impact analysis focused
on oil and gas-related and non-oil and gas-related noise-generating
events/activities in both Federal and State of Alaska waters that were
likely and foreseeable. Other appropriate factors, such as Arctic
warming, military activities, and noise contributions from community
and commercial activities were also considered. Appendix D of the PEA
addresses similar comments on cumulative impacts, including global
warming. That information was incorporated into and updated in the NMFS
2008 SEA and into this document by citation. NMFS adopted the MMS Final
PEA, and it is part of NMFS' Administrative Record.
Endangered Species Act
Comment 51: The CBD states that the proposed IHA will affect, at a
minimum, four endangered species, the bowhead, humpback and fin whales,
and the polar bear. The CBD and ICAS states that as a consequence, NMFS
must engage in consultation under Section 7 of the ESA prior to issuing
the IHA. Previous recent biological opinions for industrial activities
in the Arctic (e.g., the 2006 Arctic Regional Biological Opinion
(ARBO)) have suffered from inadequate descriptions of the proposed
action, inadequate descriptions of the status of the species,
inadequate descriptions of the environmental baseline, inadequate
descriptions of the effects of the action, inadequate analysis of
cumulative effects, and inadequate descriptions and analysis of
proposed mitigation. The CBD hopes NMFS performs the full analysis
required by law and avoids these problems in its consultation for the
proposed IHA. CPAI encourages NMFS to complete a thorough section 7
consultation with FWS to assure that coverage for polar bear and walrus
is addressed.
Response: Under section 7 of the ESA, NMFS has completed
consultation with the MMS on the issuance of seismic permits for
offshore oil and gas activities in the Beaufort and Chukchi seas. In a
Biological Opinion issued on July 17, 2008, NMFS concluded that the
issuance of seismic survey permits by MMS and the issuance of the
associated IHAs for seismic surveys are not likely to jeopardize the
continued existence of threatened or endangered species (specifically
the bowhead, humpback, and fin whales) under the jurisdiction of NMFS
or destroy or adversely modify any designated critical habitat. The
2008 Biological Opinion takes into consideration all oil and gas
related activities that are reasonably likely to occur, including
exploratory (but not production) oil drilling activities. In addition,
NMFS has issued an Incidental Take Statement under this Biological
Opinion which contains reasonable and prudent measures with
implementing terms and conditions to minimize the effects of take of
bowhead, humpback, and fin whales. Regarding the polar bear, MMS has
contacted the FWS about conducting a section 7 consultation. Walrus is
not an ESA-listed species, therefore, a section 7 consultation is not
warranted.
Comment 52: The CBD states that NMFS may authorize incidental take
of the listed marine mammals under the ESA pursuant to Section 7(b)(4)
of the ESA, but only where such take occurs while ``carrying out an
otherwise lawful
[[Page 49438]]
activity.'' To be ``lawful,'' such activities must ``meet all State and
Federal legal requirements except for the prohibition against taking in
section 9 of the ESA.'' The CBD states that CPAI's proposed activities
violate the MMPA and NEPA and therefore are ``not otherwise lawful.''
The CBD concludes that any take authorization for listed marine mammals
would, therefore, violate the ESA, as well as these other statutes.
Response: NMFS does not agree with the CBD statement. As noted in
this document, NMFS has made the necessary determinations under the
MMPA, the ESA, and NEPA regarding the incidental harassment of marine
mammals by CPAI while it is conducting activities permitted legally
under MMS' jurisdiction.
Other Comments
Comment 53: To assist with its ability to plan and coordinate its
programs in the remote area of the Chukchi Sea, CPAI requests that NMFS
expedite their decision on the IHA after the 30-day public comment
period closes on June 23, 2008.
Response: Comment noted. Nevertheless, in order to make an sound
determination regarding whether CPAI's proposed shallow hazard and site
clearance surveys would have a negligible impacts to marine mammals and
unmitigable adverse affects to subsistence harvest of marine mammals in
the Arctic region, NMFS has taken the time to thoroughly review all
relevant documents on the proposed activities. Especially as CPAI
indicated that it will not sign a CAA with the AEWC, NMFS is obligated
to review and evaluate the CAA and stipulate certain conditions in the
IHA to CPAI to ensure that the shallow hazard and site clearance survey
would not have an unmitigable adverse impact on the availability of
marine mammal species or stocks for taking for subsistence uses.
Description of Marine Mammals in the Activity Area
In general, the marine mammal species under NMFS' management
authority that occur in or near the proposed survey area within the
Chukchi Sea are the bowhead (Balaena mysticetus), gray (Eschrichtius
robustus), humpback (Megaptera novaeangliae), fin (Balaenoptera
physalus), minke (B. acutorostrata), beluga (Delphinapterus leucas),
and killer whales (Orcinus orca); harbor porpoises (Phocoena phocoena);
and the bearded (Erignathus barbatus), ringed (Phoca hispida), spotted
(P. largha), and ribbon seals (P. fasciata). Among these species, the
bowhead, humpback, and fin whales are listed as ``Endangered'' under
the Endangered Species Act (ESA).
A detailed description of the biology, population estimates, and
distribution and abundance of these species is provided in CPAI's IHA
application. Additional information regarding the stock assessments of
these species is in NMFS Alaska Marine Mammal Stock Assessment Report
(Angliss and Outlaw, 2008), and can also be assessed via the following
URL link: http://www.nmfs.noaa.gov/pr/pdfs/sars/ak2007.pdf. Additional
information on those species that are under NMFS' management authority
within or near the proposed survey areas is described in the FR Notice
of Proposed IHA and is not repeated here.
Potential Effects on Marine Mammals
Operating a variety of acoustic equipment such as side-scan sonars,
echo-sounders, bottom profiling systems, and airguns for seafloor
imagery, bathymetry, and seismic profiling has the potential for
adverse affects on marine mammals.
Potential Effects of Airgun Sounds on Marine Mammals
The effects of sounds from airguns might include one or more of the
following: tolerance, masking of natural sounds, behavioral
disturbance, and, at least in theory, temporary or permanent hearing
impairment, or non-auditory physical or physiological effects
(Richardson et al., 1995)
The potential effects of airguns discussed below are presented
without consideration of the mitigation measures that CPAI has
presented and that will be required by NMFS. When these measures are
taken into account, it is unlikely that this project would result in
temporary, or especially, permanent hearing impairment or any
significant non-auditory physical or physiological effects.
(1) Tolerance
Numerous studies have shown that pulsed sounds from airguns are
often readily detectable in the water at distances of many kilometers.
Studies have also shown that marine mammals at distances more than a
few kilometers from operating seismic vessels often show no apparent
response (tolerance). That is often true even in cases when the pulsed
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 airgun pulses under
some conditions, at other times mammals of all three types have shown
no overt reactions. In general, pinnipeds, and small odontocetes seem
to be more tolerant of exposure to airgun pulses than are baleen
whales.
(2) Masking
Masking effects of pulsed sounds (even from large arrays of
airguns) on marine mammal calls and other natural sounds are expected
to be limited, although there are very few specific data of relevance.
Some whales are known to continue calling in the presence of seismic
pulses. Their calls can be heard between the seismic pulses (e.g.,
Richardson et al., 1986; McDonald et al., 1995; Greene et al., 1999;
Nieukirk et al., 2004). Although there has been one report that sperm
whales cease calling when exposed to pulses from a very distant seismic
ship (Bowles et al., 1994), a more recent study reports that sperm
whales off northern Norway continued calling in the presence of seismic
pulses (Madsen et al., 2002). That has also been shown during recent
work in the Gulf of Mexico (Tyack et al., 2003; Smultea et al., 2004).
Masking effects of seismic pulses are expected to be negligible in the
case of the smaller odontocete cetaceans, given the intermittent nature
of seismic pulses. Dolphins and porpoises commonly are heard calling
while airguns are operating (e.g., Gordon et al., 2004; Smultea et al.,
2004; Holst et al., 2005a; 2005b). Also, the sounds important to small
odontocetes are predominantly at much higher frequencies than are
airgun sounds.
(3) Disturbance Reactions
Disturbance includes a variety of effects, including subtle changes
in behavior, more conspicuous changes in activities, and displacement.
Reactions to sound, if any, depend on species, state of maturity,
experience, current activity, reproductive state, time of day, and many
other factors. If a marine mammal does react briefly to an underwater
sound by slightly changing its behavior or moving a small distance, the
impacts of the change are unlikely to be biologically significant to
the individual, let alone the stock or the species as a whole. However,
if a sound source displaces marine mammals from an important feeding or
breeding area for a prolonged period, impacts on the animals could be
significant.
(4) Hearing Impairment and Other Physical Effects
Temporary or permanent hearing impairment is a possibility when
marine
[[Page 49439]]
mammals are exposed to very strong sounds, but there has been no
specific documentation of this for marine mammals exposed to sequences
of airgun pulses. NMFS advises against exposing cetaceans and pinnipeds
to impulsive sounds above 180 and 190 dB re 1 microPa (rms),
respectively (NMFS, 2000). Those thresholds have been used in defining
the safety (shut down) radii planned for the proposed seismic surveys.
Although those thresholds were established before there were any data
on the minimum received levels of sounds necessary to cause temporary
auditory impairment in marine mammals, they are considered to be
conservative.
Several aspects of the planned monitoring and mitigation measures
for this project are designed to detect marine mammals occurring near
the airguns to avoid exposing them to sound pulses that might, at least
in theory, cause hearing impairment (see Mitigation and Monitoring
section below). In addition, many cetaceans are likely to show some
avoidance of the area with high received levels of airgun sound. In
those cases, the avoidance responses of the animals themselves will
reduce or (most likely) avoid any possibility of hearing impairment.
Non-auditory physical effects may also occur in marine mammals
exposed to strong underwater pulsed 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. It is possible that some marine mammal species (i.e.,
beaked whales) may be especially susceptible to injury and/or stranding
when exposed to strong pulsed sounds. However, there is no definitive
evidence that any of these effects occur even for marine mammals in
close proximity to large arrays of airguns. It is unlikely that any
effects of these types would occur during the proposed project given
the brief duration of exposure of any given mammal, and the planned
monitoring and mitigation measures (see below).
(5) Strandings 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 have slower rise times, and there
is no evidence that they can cause serious injury, death, or stranding
even in the case of large airgun arrays.
Nonetheless, the airgun array proposed to be used in the proposed
site clearance surveys in Chukchi Sea is small in volume (40 cu inches)
and the source level is expected at 196 dB re 1 mircoPa (peak), which
is approximately 190 dB re 1 microPa (rms). The 160, 170, and 180 dB re
1 microPa (rms) radii, in the beam below the transducer, would be 32 m
(104 ft), 10 m (33 ft), and 3.2 m (10 ft), respectively, for the 40-cu-
inch airgun array, assuming spherical spreading.
Possible Effects of Bathymetry Echo Sounder Signals
Two types of bathymetry echo sounders are planned to be used for
the proposed surveys. The Odom Hydrotrac Digital Echo Sounder is a
single beam echo sounder that emits a single pulse of sound directly
below the ship along the vessel trackline and provides a continuous
recording of water depth along the survey track. The second sonar is a
Reson Seabat 8101 Multibeam Echo Sounder, which consists of a
transducer array that emits a swath of sound. The seafloor coverage
swath of the multibeam sonar is water depth dependent, but is usually
equal to two to four times the water depth. Nonetheless both echo
sounders produce acoustic signals above 200 kHz which is above any
marine mammal species' upper hearing threshold, therefore, NMFS does
not believe that there will be any effects on marine mammals as a
result from operating these sonars.
Possible Effects of Sub-bottom Profiler Signals
A high resolution subbottom profiler (GeoAcoustics GeoPulse sub-
bottom profiling system or GeoAcoustics GeoChirp II sub-bottom
profiling system) and an intermediate frequency seismic profiling
system (``boomer'') are planned to be used for the proposed surveys.
The frequency range for these high resolution subbottom profilers
are 3.5 to 5 kHz for the GeoPulse and 500 Hz to 13 kHz for the GeoChirp
II. Either subbottom profiler has a source level at approximately 214
dB re 1 microPa-m (rms). The 160, 170, 180, and 190 dB re 1 microPa
(rms) radii, in the beam below the transducer, would be 501 m (1,644
ft), 158 m (520 ft), 50 m (164 ft), and 16 m (52 ft), respectively, for
either subbottom profiler, assuming spherical spreading.
The Applied Acoustics Model AA300 intermediate frequency seismic
profiler (``boomer'') has a maximum energy input of 350 J per shot,
though the maximum energy would be used in the surveys is 300 J. The
pulse length ranges from 150 msec to 400 msec with a reverberation of
less than 1/10 of the initial pulse. The peak in the source level beam
reaches 218 dB re 1 microPa-m (or 209 dB re 1 microPa-m (rms)) at 300 J
with a frequency range of 500 Hz to 300 kHz. The 160, 170, 180, and 190
dB re 1 microPa (rms) radii, in the beam below the transducer, would be
282 m (925 ft), 89 m (292 ft), 28 m (92 ft), and 9 m (29 ft),
respectively, assuming spherical spreading.
The corresponding distances for an animal in the horizontal
direction of these transducers would be much smaller due to the direct
downward beam pattern of the subbottom profilers. Therefore, the
horizontal received levels of 180 and 190 dB re 1 microPa (rms) would
be within much smaller radii than 50 m (164 ft) and 16 m (52 ft) when
using the GeoAcoustics subbottom profilers, which have the highest
downward source level, respectively. In addition, the pulse duration of
these subbottom profilers is extremely short, in the order of tens to
hundreds of msec, and the survey is constantly moving. Therefore, for a
marine mammal to receive prolonged exposure, the animal has to stay in
a very small zone of ensonification and keep with the vessel's speed,
which is very unlikely.
Possible Effects of Side-Scan Sonar Signals for Seafloor Imagery
One of the two types of side-scan sonars is planned to be used for
the proposed shallow hazard and site clearance surveys for seafloor
imagery. The EdgeTech 4200 dual-frequency side scan sonar operates at
120 kHz up to 410 kHz, with source level reaching 210 dB re 1 microPa-m
(rms). The 160, 170, 180, and 190 dB re 1 microPa (rms) radii, in the
beam below the transducer, would be 316 m (1,037 ft), 100 m (328 ft),
32 m (104 ft), and 10 m (33 ft), respectively, assuming spherical
spreading.
The Klein System 3000 dual-frequency digital side-scan sonar emits
pulses between 25 msec and 400 msec. The peak in the 132 kHz source
level beam reaches 234 dB re 1 microPa-m (or 225 dB re 1 microPa-m
(rms)). The peak in the 445 kHz source level beam reaches 242 dB re 1
microPa-m. The 445 kHz frequency band is outside any marine mammal
species' hearing range, therefore, there would be no effect to marine
mammals when this frequency is chosen. The 160, 170, 180, and 190 dB re
1 microPa (rms) radii, in the beam below the transducer, would be 1,778
m (5,834 ft), 562 m (1,844 ft), 178 m (583 ft), and 56 m (184 ft),
respectively, assuming spherical spreading.
[[Page 49440]]
Nonetheless, these side scan sonars operate in an extremely high
frequency range (over 120 kHz) relative to marine mammal hearing
(Richardson et al., 1995; Southall et al., 2007). The frequency range
from these side scan sonars is beyond the hearing range of mysticetes
(baleen whales) and pinnipeds. Therefore, these sonars are not expected
to affect bowhead, gray, humpback, fin, and minke whales and pinniped
species in the proposed project area. The frequency range from these
side scan sonars falls within the upper end of odontocete (toothed
whale) hearing spectrum (Richardson et al., 1995), which means that
they are not perceived as loud acoustic signals with frequencies below
120 kHz by these animals. Therefore, these animals would not react to
the sound in a biologically significant way. Further, in addition to
spreading loss for acoustic propagation in the water column, high
frequency acoustic energies are more quickly absorbed through the water
column than sounds with lower frequencies (Urick, 1983). Therefore,
NMFS believes that the potential effects from side scan sonar to marine
mammals are negligible.
Numbers of Marine Mammals Estimated to be Taken
All anticipated takes would be takes by Level B harassment,
involving temporary changes in behavior. The proposed mitigation
measures to be applied would prevent the possibility of injurious
takes.
Take was calculated for the two areas of the study area using
vessel-based density estimates. Few bowheads and no belugas were
observed during the vessel surveys conducted in the Chukchi Sea by LGL
et al. (2008), although the surveys used multiple vessels achieving
substantial effort and coverage from early July to mid November. This
result is generally consistent with the historic information, which
shows that bowheads generally migrated through the Chukchi Sea to the
Beaufort Sea by mid-late June, and do not return until about late
October and November, probably reaching the region of the project area
no earlier than late October (LGL et al., 2008). Similarly, most
belugas migrate to the northern Chukchi Sea and westward into the
Beaufort Sea by mid to late July and return to the region of the
project area in late October and November (Suydam et al., 2005).
Although LGL et al., (2008) did not observe belugas offshore in 2006 or
2007, they did encounter belugas along the coast in decreasing numbers
from July to October/November during aerial surveys. LGL et al. (2008)
also observed bowheads in the fall near Barrow during nearshore aerial
surveys, suggesting the whales had not moved very far into Chukchi Sea
at that time. While these data and the historic information suggest the
take calculations are reasonable for belugas and bowheads, the take
numbers have been adjusted to 10 animals for each species to account
for the possible occurrence of more animals than estimated in the
project area during operations due to an early freeze-up or other
unanticipated changes in the environment. This adjustment is generally
consistent with estimates based on less current densities used in past
IHAs for bowhead (0.0011/km2) and beluga (0.0034/km\2\) whales for late
fall.
The vessel-based density estimates for ringed and spotted seals
were reported in the LGL et al. (2008) study as a combined estimate for
the two species, since observers were not able to distinguish the two
species in the open water. However, since ringed seals typically
comprise almost 95 percent of the combined ringed/spotted seal
sightings recorded during surveys in offshore waters of the Chukchi Sea
during 1989-1991 (Brueggeman et al., 1990; 1991; 1992), the LGL et al.
(2008) ringed/spotted seal data were corrected by applying 95 percent
of the sightings as ringed, and 5 percent as spotted seals,
respectively.
JASCO modeled the sound levels of different configurations of
seismic profilers (10 kj and 16 kj sparkers, 10 in\3\ and 20 in\3\ 2-
gun arrays, 40 cu\3\ single gun, and 10 in\3\ 4-gun array) and found
the 4-gun array produced the highest sound levels. Therefore, all take
estimates of marine mammals are calculated for the 4-gun array in this
proposed activity, which reaches the 160 dB re 1 microPa sound level at
1,665 m (5,463 ft) from the source, the 180 dB re 1 microPa level at
115 m (377 ft), and the 190 dB level at 20 m (66 ft).
The average estimates of ``take'' were calculated by multiplying
the expected average animal densities by the area of ensonification for
the 160 dB re 1 microPa (rms). The area of ensonification was
determined by multiplying the total proposed trackline of 5,300 km
(3,294 mi)(2,120 km, or 1,318 mi, in August; 2,120 km, or 1,318 mi, in
September; and 1,060 km, or 659 mi, in October) times 2 (both sides of
the trackline) times the distance to the 160-dB isopleth. The distance
to the 160-dB isopleth was estimated as approximately 1,665 m (5,463
ft) with a corresponding area of ensonification of 17,649 km\2\ (6,817
mi\2\).
The Level B harassment take estimate of 1,379 ringed seals is a
small number at least in relative terms, in that it represents
approximately 0.55 percent of the Alaska stock size of that species
(249,000) in the Chukchi Sea, if each ``exposure'' at 160 dB represents
an individual ringed seal. The percentage would be even lower if a
higher SPL is required for a behavioral reaction (as is expected), or,
if as expected, animals move out of the seismic area. As a result, we
believe that these ``exposure'' estimates are conservative, and seismic
surveys will actually affect less than 0.55 percent of the ringed seal
population. For the remaining potentially affected marine mammal
species, NMFS expects that approximately 10 bowhead, 37 gray whales, 42
harbor porpoises, and 376 bearded seals would be taken by Level B
behavioral harassment as a result of the proposed site clearance
surveys. These take numbers represent 0.09, 0.19, 0.66, and 0.15
percent of the western Arctic stock of bowhead whales, eastern North
Pacific stock of gray whales, Bering Sea stock of harbor porpoise, and
Arctic stock of bearded seals in the Chukchi Sea region. These numbers
are small relative to their respective stock or population sizes. In
addition, NMFS expects that 4 minke whales and 72 spotted seals would
be taken by Level B harassment. However, a specific estimate of the
percentage of Level B harassment of these species cannot be determined
because no accurate current population estimates of minke whales and
spotted seals are available. Nevertheless, based on the information
available, NMFS believes these numbers are very low relative to the
populations of these species in the proposed project area because: (1)
for the minke whales, the Chukchi Sea is not typical habitat, and
visual surveys in 1999 and 2000 counted 810 and 1,003 minke whales in
the central-eastern and southeastern Bering Sea, respectively, not
including animals missed on the trackline, or animals submerged when
the ship passed; and (2) for the spotted seal, the early population
estimate of this species ranged from 335,000-450,000 seals, and there
is no reason to believe that the population of this species has
declined significantly. In addition, a number of beluga, humpback, and
killer whales, and ribbon seals could also be affected by Level B
behavioral harassment as a result of the proposed marine surveys in the
Chukchi Sea. However, since the occurrence of these marine mammals is
very rare within the proposed project area during the late summer and
fall in the Chukchi Sea, take numbers cannot be estimated. In the event
these species
[[Page 49441]]
are present in the proposed project area, NMFS believes their numbers
would be limited; thus, should take occur from the seismic survey, NMFS
would expect the numbers to be small, particularly in light of the fact
that these animals do not frequent the project area.
NMFS believes the number of potential takes by harassment is small
and may be reduced further because of the proposed mitigation measures,
including curtailing seismic activities during the bowhead migratory
period to protect the Native subsistence hunt. Additionally, because
the seismic airguns used by CPAI are of small discharge volumes (40
in\3\, compared to the 3,000+ in\3\ arrays used in 2D or 3D deep
seismic surveys), the ensonified zones within which marine mammals
could be adversely affected are very small (approximately 50 km\2\ for
the 160-dB isopleths at any given time as compared to 15,000 km2 for a
3,000+ in\3\ array [e.g., SOI's proposed 3D seismic survey in the
Chukchi Sea]).
Potential Impacts to Subsistence Harvest of Marine Mammals
Subsistence hunting and fishing has historically, and continues to
be, an essential aspect of Native life, especially in rural coastal
villages. The Inupiat participate in subsistence hunting and fishing
activities in and around the Chukchi Sea.
Alaska Natives, including the Inupiat, legally hunt several species
of marine mammals. Communities that participate in subsistence
activities potentially affected by seismic surveys within the proposed
survey areas are Point Hope, Point Lay, Wainwright, and Barrow. Marine
mammals used for subsistence in the proposed area include: bowhead
whales, beluga whales, ringed seals, spotted seals, bearded seals,
Pacific walrus, and polar bears. In each village, there are key
subsistence species. Hunts for these animals occur during different
seasons throughout the year. Depending upon the village's success of
the hunt for a certain species, another species may become a priority
in order to provide enough nourishment to sustain the village.
Point Hope residents hunt for bowhead and beluga whales, polar
bears and walrus. Bowhead and beluga whales are hunted in the spring
and early summer along the ice edge. Beluga whales may also be hunted
later in the summer along the shore. Walrus are harvested in late
spring and early summer, and polar bear are hunted from October to
April (MMS, 2007). Seals are available from October through June, but
are harvested primarily during the winter months, from November through
March, due to the availability of other resources during the other
periods of the year (MMS, 2007).
With Point Lay situated near Kasegaluk Lagoon, the community's main
subsistence focus is on beluga whales. Seals are available year-round,
and polar bears and walruses are normally hunted in the winter. Hunters
typically travel to Barrow, Wainwright, or Point Hope to participate in
bowhead whale harvest, but there is interest in reestablishing a local
Point Lay harvest.
Wainwright residents subsist on both beluga and bowhead whales in
the spring and early summer. During these two seasons the chances of
landing a whale are higher than during other seasons. Seals are hunted
by this community year-round and polar bears are hunted in the winter.
Barrow residents' main subsistence focus is concentrated on
biannual bowhead whale hunts. They hunt these whales during the spring
and fall. Other animals, such as seals, walruses, and polar bears are
hunted outside of the whaling season, but they are not the primary
source of the subsistence harvest (URS Corporation, 2005).
The potential impact of the noise produced by the proposed survey
on subsistence could be substantial. If bowhead or beluga whales are
permanently deflected away from their migration path, there could be
significant repercussions to the subsistence use villages. However,
mitigation efforts will be put into action to minimize or avoid
completely any adverse affects on all marine mammals.
In an effort to minimize or avoid any adverse effects to
subsistence harvest, CPAI has met with key native organizations
responsible for managing marine mammals in the Arctic. In accordance
with 50 CFR 126.104(a)(12), CPAI has met with subsistence stakeholder
in the communities and villages of Kivalina, Kotzebue, Wainwright,
Barrow, Point Lay, and Point Hope and developed a POC for its proposed
2008 shallow hazard and site clearance survey.
CPAI has not signed the 2008 CAA with Alaska Natives and has
informed NMFS that it does not intend to do so. As explained above in
Response to Comment 33, NMFS has scrutinized all of the documents
submitted by CPAI (e.g., IHA application, Plan of Cooperation and other
correspondence to NMFS and affected stakeholders) and documents
submitted by other affected stakeholders and concluded that harassment
of marine mammals incidental to CPAI's activities will not have an
unmitigable adverse impact on the availability of marine mammals for
taking for subsistence uses.
In addition, CPAI has indicated that a number of actions would be
taken by CPAI during the surveys to minimize any adverse effect on the
availability of marine mammals for subsistence, which have been
proposed in the CPAI application. They include the following:
(1) Site clearance and shallow hazard surveys will occur in areas
considerably distant to the villages during the hunting periods (i.e.,
up to 70 miles offshore);
(2) Site clearance and shallow hazard surveys will follow
procedures of changing vessel course, powering down, and shutting down
acoustic equipment to minimize effects on the behavior of marine
mammals. These measures are likely to afford greater access by
subsistence users to marine mammals should any harvest occur in the
project area; and
(3) In the unlikely event that a hunter is encountered, operations
will be managed to keep the hunter and seismic vessel at least 5 km
(3.1 mi) apart.
The combination of the low volume air guns, timing, location,
mitigation measures, and input from local communities and organization
is expected to mitigate any adverse effect of the seismic surveys on
availability of marine mammals for subsistence uses.
Finally, in the event harvest activities do occur this far
offshore, the required mitigation and monitoring measures are expected
to reduce any adverse impacts on marine mammals for taking for
subsistence uses to the extent practicable. These measures include, but
are not limited to, the 180 dB and 190 dB safety (shut-down/power-down)
zones; a requirement to monitor the 160 dB isopleth for aggregations of
12 or more non-migratory balaenidae whales and when necessary shut-down
seismic airguns; maintaining a distance of at least 15 miles from other
operating seismic vessels; reducing vessel speed when a vessel is
within 300 yards of whales to avoid a collision; utilizing
communication centers to avoid any conflict with subsistence hunting
activities; and the use of marine mammal observers. Many of these
requirements are consistent with the measures contained in the 2008 CAA
entered into between other industry participants who operate in the
Chukchi Sea and Alaska Natives.
Potential Impacts on Habitat
The proposed site clearance surveys would not result in any
permanent impact on habitats used by marine mammals, or to the food
sources they use. The main impact issue associated
[[Page 49442]]
with the proposed activity would be temporarily elevated noise levels
and the associated direct effects on marine mammals, as discussed
above.
Monitoring and Mitigation Measures
Monitoring
In order to further reduce and minimize the potential impacts to
marine mammals from the proposed site clearance surveys, NMFS requires
the following monitoring and mitigation measures to be implemented for
the proposed project in Chukchi Sea.
(1) Proposed Safety Zones
Based acoustic propagation modeling performed by JASCO, it is
estimated that distance from the seismic sources to the 180 dB isopleth
is approximately 115 m (377 ft), and the distance to the 190 dB
isopleth is about 20 m (66 ft). Because these values are based on
modeling instead of field measurement during actual operations, NMFS
requires, as a precautionary measure, safety radii of 120 m (393 ft)
for cetaceans and 24 m (79 ft) for pinnipeds.
In addition, a 160-dB vessel monitoring zone for bowhead and gray
whales shall be established and monitored during all seismic surveys.
Whenever an aggregation of 12 or more bowhead whales or gray whales are
observed during a vessel monitoring program within the 160-dB safety
zone around the seismic activity, the seismic operation will not
commence, or will shut down, until two consecutive surveys indicate
they are no longer present within the 160-dB safety zone of seismic-
surveying operations. The radius of 160-dB isopleth based on modeling
is 1,665 m (5,463 ft).
Before the commencement of the shallow hazard and site clearance
survey, CPAI is required to conduct empirical measurements of acoustic
sources to be used in the seismic survey and verify the radii of the
modeled safety zones at 160, 170, 180, and 190 dB re 1 microPa (rms).
(2) Vessel-based Visual Monitoring
Marine mammal monitoring during the site clearance surveys would be
conducted by qualified, NMFS-approved marine mammal observers (MMOs).
Vessel-based MMOs would be on board the seismic source vessel to ensure
that no marine mammals would enter the relevant safety radii of 180 and
190-dB isopleths while noise-generating equipment is operating.
Monitoring will also be conducted to include the larger 160-dB safety
zone for an aggregation of 12 or more bowhead or gray whales.
(3) Communication between Vessel and Shore
Communication of vessel operations and transit would occur in
accordance with protocols set forth by the Com and Call Centers
proposed to be operated in Barrow, Point Hope, and Point Lay. This
would further enable vessel operators to be aware of marine mammals and
subsistence activity in the area.
Mitigation
Mitigation measures include (1) vessel speed or course alteration,
provided that doing so will not compromise operational safety
requirements, (2) acoustic equipment shut down, and (3) acoustic source
ramp up.
(1) Speed or Course Alteration
If a marine mammal is detected outside the relevant safety zone but
appears likely to enter it based on relative movement of the vessel and
the animal, then if safety and survey objectives allow, the vessel
speed and/or course would be adjusted to minimize the likelihood of the
animal entering the safety zone.
(2) Shut down Procedures
If a marine mammal is detected within, or appears likely to enter,
the relevant safety zone of the array in use, and if vessel course and/
or speed changes are impractical or will not be effective to prevent
the animal from entering the safety zone, then the acoustic sources
that relate to the seismic surveys would be shut down.
Following a shut down, acoustic equipment would not be turned on
until the marine mammal is outside the safety zone. The animal would be
considered to have cleared the safety zone if it (1) is visually
observed to have left the 120-m or 24-m safety zone, for a cetacean or
a pinniped species, respectively; or (2) has not been seen within the
relevant safety zone for 15 minutes in the case of odontocetes and
pinnipeds, and for 30 minutes in the case of mysticetes. For the
aggregation of bowhead or gray whales, the seismic equipment will not
be turned on until the aggregation has left the 1,665-m safety zone or
the animals forming the aggregation are reduced to fewer than 12
bowhead or gray whales.
Following a shut down and subsequent animal departure as above, the
acoustic sources may be turned on to resume operations following ramp-
up procedures described below.
(3) Ramp-up Procedures
A ramp-up procedure will be followed when the acoustic sources
begin operating after a specified period without operations. It is
proposed that, for the present survey, this period would be 30 min.
Ramp up would begin with the power on of the smallest acoustic
equipment for the survey at its lowest power output. The power output
would be gradually turned up and other acoustic sources would be added
in a way such that the source level would increase in steps not
exceeding 6 dB per 5-min period. During ramp-up, the MMOs would monitor
the safety zone, and if marine mammals are sighted, decisions about
course/speed changes and/or shutdown would be implemented as though the
acoustic equipment is operating at full power.
(4) Poor Visibility Conditions
CPAI plans to conduct 24-hr operations. The proposed provisions
associated with operations at night or in periods of poor visibility
include:
(1) During any nighttime operations, if the entire 180-dB safety
radius is visible using vessel lights and/or night vision devices, then
start of a ramp-up procedure after a complete shutdown of the airgun
array may occur following a 30-min period of observation without
sighting marine mammals in the safety zone.
(2) If during foggy conditions or darkness (which may be
encountered starting in late August), the full 180-dB safety zone is
not visible, the airguns cannot be ramped-up if the seismic source is
in a full shutdown mode.
(3) If one or more airguns has been operational before nightfall or
before the onset of foggy conditions, they can remain operational
throughout the night or foggy conditions. In this case, ramp-up
procedures can be initiated, even though the entire safety radius may
not be visible, on the assumption that marine mammals will be alerted
by the sounds from the single airgun and have moved away.
Data Collection and Reporting
MMOs would record data to estimate the numbers of marine mammals
present and to document apparent disturbance reactions or lack thereof.
Data would be used to estimate numbers of animals potentially ``taken''
by harassment. They would also provide information needed to order a
shut down of acoustic equipment when marine mammals are within or
entering the safety zone.
When a sighting is made, the following information about the
sighting would be recorded:
(1) Species, group size, age/size/sex categories (if determinable),
behavior when first sighted and after initial sighting, heading (if
consistent), bearing
[[Page 49443]]
and distance from seismic vessel, and apparent reaction to the acoustic
sources or vessel.
(2) Time, location relative to the acoustic sources, heading,
speed, activity of the vessel (including whether and the level at which
acoustic sources are operating), sea state, visibility, and sun glare.
The data listed under (2) would also be recorded at the start and
end of each observation watch, and during a watch whenever there is a
change in one or more of the variables.
A final report will be submitted to NMFS within 90 days after the
end of the shallow hazard and site clearance surveys. The report will
describe the operations that were conducted and sightings of marine
mammals near the operations. The report also will provide full
documentation of methods, results, and interpretation pertaining to all
monitoring. The report will summarize the dates and locations of
seismic operations, and all marine mammal sightings (dates, times,
locations, activities, associated seismic survey activities), and the
amount and nature of potential take of marine mammals by harassment or
in other ways.
Endangered Species Act
Under section 7 of the ESA, NMFS has completed consultation with
the MMS on the issuance of seismic permits for offshore oil and gas
activities in the Beaufort and Chukchi seas. In a Biological Opinion
issued on July 17, 2008, NMFS concluded that the issuance of seismic
survey permits by MMS and the issuance of the associated IHAs for
seismic surveys are not likely to jeopardize the continued existence of
threatened or endangered species (specifically the bowhead, humpback,
and fin whales) under the jurisdiction of NMFS or destroy or adversely
modify any designated critical habitat. The 2008 Biological Opinion
takes into consideration all oil and gas related activities that are
reasonably likely to occur, including exploratory (but not production)
oil drilling activities. In addition, NMFS has issued an Incidental
Take Statement under this Biological Opinion which contains reasonable
and prudent measures with implementing terms and conditions to minimize
the effects of take of bowhead whales.
NEPA
In 2006, the MMS prepared Draft and Final PEAs for seismic surveys
in the Beaufort and Chukchi Seas. NMFS was a cooperating agency in the
preparation of the MMS PEA. On November 17, 2006 (71 FR 66912), NMFS
and MMS announced that they were preparing a DPEIS in order to assess
the impacts of MMS' annual authorizations under the Outer Continental
Shelf Lands Act to the U.S. oil and gas industry to conduct offshore
geophysical seismic surveys in the Chukchi and Beaufort Seas off Alaska
and NMFS' authorizations under the MMPA to incidentally harass marine
mammals while conducting those surveys.
On March 30, 2007 (72 FR 15135), the Environmental Protection
Agency (EPA) noted the availability for comment of the NMFS/MMS DPEIS.
Based upon several verbal and written requests to NMFS for additional
time to review the DPEIS, EPA has twice announced an extension of the
comment period until July 30, 2007 (72 FR 28044, May 18, 2007; 72 FR
38576, July 13, 2007). Because NMFS has been unable to complete the
PEIS, it was determined that the 2006 PEA would need to be updated in
order to meet NMFS' NEPA requirement. This approach was warranted as it
was reviewing five proposed Arctic seismic survey IHAs for 2008, well
within the scope of the PEA's eight consecutive seismic surveys. To
update the 2006 Final PEA, NMFS prepared a SEA which incorporates by
reference the 2006 Final PEA and other related documents.
Determination
Based on the preceding information, and provided that the
mitigation and monitoring are incorporated, NMFS has determined that
the impact of conducting the shallow hazard and site clearance surveys
in Chukchi Sea may result, at worst, in a temporary modification in
behavior of small numbers of certain species of marine mammals. While
behavioral and avoidance reactions may be made by these species in
response to the resultant noise from the airguns, side-scan sonars,
seismic profilers, and other acoustic equipment, these behavioral
changes are expected to have a negligible impact on the affected
species and stocks of marine mammals. In addition, NMFS has determined
that the CPAI's shallow hazard and site clearance survey would no have
an unmitigable adverse impact on the availability of marine mammal
species and/or stocks for taking for subsistence uses.
While the number of potential incidental harassment takes will
depend on the distribution and abundance of marine mammals in the area
of site clearance operations, the number of potential harassment
takings is estimated to be small relative to the species' population or
stock size. NMFS anticipates the actual take of individuals would be
lower than the numbers presented in the analysis because those numbers
do not reflect either the implementation of the mitigation measures or
the fact that some animals will avoid the sound at levels lower than
those expected to result in harassment.
In addition, no take by death and/or injury is anticipated, and the
potential for temporary or permanent hearing impairment will be avoided
through the incorporation of the required mitigation measures described
in this document. This determination is supported by (1) the likelihood
that, given sufficient notice through slow ship speed and ramp-up of
the acoustic equipment, marine mammals are expected to move away from a
noise source that it is annoying prior to its becoming potentially
injurious; (2) TTS is unlikely to occur, especially in odontocetes,
until levels much above 180 dB re 1 microPa (rms) are reached; and (3)
the fact that injurious levels of sound are only likely if an animal is
very close to the vessel.
Authorization
As a result of these determinations, NMFS has issued an IHA to CPAI
for conducting a shallow hazard and site clearance survey in the
Chukchi Sea in 2008, provided the previously mentioned mitigation,
monitoring, and reporting requirements are incorporated.
Dated: August 15, 2008.
James H. Lecky,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. E8-19424 Filed 8-20-08; 8:45 am]
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