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Incidental Takes of Marine Mammals During Specified Activities; Low-Energy Marine Seismic Survey in the Northeast Pacific Ocean, July 2009

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[Federal Register: July 17, 2009 (Volume 74, Number 136)]
[Notices]
[Page 34715-34725]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr17jy09-22]

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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XO71

Incidental Takes of Marine Mammals During Specified Activities;
Low-Energy Marine Seismic Survey in the Northeast Pacific Ocean, July 2009

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an incidental take authorization.

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SUMMARY: In accordance with the Marine Mammal Protection Act (MMPA)
regulations, notification is hereby given that NMFS has issued an
Incidental Harassment Authorization (IHA) to Scripps Institution of
Oceanography (SIO), a part of the University of California San Diego
(UCSD), for the take of small numbers of marine mammals, by Level B
harassment only, incidental to conducting a marine seismic survey in
the Northeast Pacific Ocean during July 2009.

DATES: Effective July 14, 2009, through August 14, 2009.

ADDRESSES: A copy of the IHA and the application are available 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 the contact listed here. A copy of the application
containing a list of the references used in this document may be
obtained by writing to the address specified above, telephoning the
contact listed below (see FOR FURTHER INFORMATION CONTACT), or visiting
the Internet at: http://www.nmfs.noaa.gov/pr/permits/
incidental.htm#applications. Documents cited in this notice may be
viewed, by appointment, during regular business hours, at the
aforementioned address.

FOR FURTHER INFORMATION CONTACT: Howard Goldstein or Ken Hollingshead,
Office of Protected Resources, NMFS, 301-713-2289.

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 United
States 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 for incidental taking shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses, 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''].

16 U.S.C. 1362(18).
    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
small numbers of marine mammals. Within 45 days of the close of the
comment period, NMFS must either issue or deny issuance of the authorization.

Summary of Request

    On March 9, 2009, NMFS received an application from SIO for the
taking, by Level B harassment only, of small numbers of marine mammals
incidental to conducting, under cooperative agreement with the National
Science Foundation (NSF), a low-energy marine seismic survey in the
Northeast Pacific Ocean. The funding for the survey is provided by the
NSF. The proposed survey will occur in an overall area between
approximately 44[deg] and 45[deg] N. and 124.5[deg] and 126[deg] W.
within the Exclusive Economic Zone (EEZ) of the U.S.A., and is
scheduled to occur from July 14-20, 2009. The survey will use a single
Generator Injector (GI) airgun with a discharge volume of 45 in\3\.
Some minor deviation from these dates is possible, depending on
logistics and weather.
    The survey is virtually identical to one conducted by SIO in 2007
under an IHA issued in September 2007 (NMFS, 2007). The SIO 2009 IHA
application contains minor updates to the project description, updated
marine mammal population sizes based on the most recent NMFS annual
stock assessment, an assessment of the relevance of the marine mammal
density and distribution data contained in the SIO 2007 IHA application
based on cruise reports from the NMFS SWFSC ORCAWHALE 2008 cruise, and
updated information on effects of airguns on marine mammals (see
Appendix A of SIO's application).

Description of the Specified Activity

    SIO plans to conduct an ocean bottom seismograph (OBS) deployment
and a magnetic, bathymetric, and seismic survey. The planned survey
will involve one source vessel, the R/V Wecoma (Wecoma), and will occur
in the Northeast Pacific Ocean off the coast of Oregon.
    The purpose of the research program is to record micro-earthquakes in the

[[Page 34716]]

forearc to determine whether seismicity on the plate boundary is
characteristic of a locked or a freely slipping fault plane. Several
earthquakes large enough to be recorded on land-based seismic nets have
occurred along this segment in the past several years. The occurrence
of ``repeating earthquakes'' (earthquakes with identical waveforms
indicating repeated rupture of almost the same fault patch) suggests
that this region is at a boundary between a freely slipping and a
locked portion of the fault. Some models suggest that the forearc basin
north of the seismically active zone may be locked; others suggest that
portion of the fault is slipping freely. OBSs have been deployed for a
year, and a seismic survey will be used to characterize the shallow
sediment structure around the instruments. Also, included in the
research is the use of a magnetometer and sub-bottom profiler.
    The source vessel, the Wecoma, will deploy a single low-energy GI
airgun as an energy source (with a discharge volume of 45 in\3\) and a
300 m (984 ft), 16 channel, towed hydrophone streamer. Sixteen OBSs
were deployed in July and September, 2008. They will continue to
acquire data during this cruise, and will be recovered before returning
to port. The energy to the GI airgun is compressed air supplied by
compressors onboard the source vessel. As the GI airgun is towed along
the survey lines, the receiving systems will receive the returning
acoustic signals.
    The seismic program will consist of approximately 21 km (13 mi) of
surveys over each of the 16 OBSs (see Figure 1 of SIO's application).
Water depths at the seismic survey locations rang from just less than
100 m (328 ft) to almost 3,000 m (9,842 ft) (see Figure 1 of SIO's
application). The GI airgun will be operated on a small grid for
approximately two hours at each of the 16 OBS sites. There will be
additional seismic operations associated with equipment testing, start-ups,
and repeat coverage of any areas where initial data quality is substandard.
    All planned geophysical data acquisition activities will be
conducted by SIO with on-board assistance by the scientists who have
proposed the study. The Chief Scientist is Dr. Anne Trehu of Oregon
State University. The vessel will be self-contained, and the crew will
live aboard the vessel for the entire cruise.
    In addition to the seismic operations of the single GI airgun, a
3.5 and 12 kHz sub-bottom profiler will be used continuously throughout
the cruise, and a magnetometer may be run on the transit between OBS locations.

Vessel Specifications

    The Wecoma has a length of 56.4 m (185 ft), a beam of 10.1 m (33.1
ft), and a maximum draft of 5.6 m (18.4 ft). The ship is powered by a
single 3,000-hp EMD diesel engine driving a single, controllable-pitch
propeller through a clutch and reduction gear, and an electric 350-hp
azimuthing bow thruster. An operations speed of 11.1 km/hour (6 knots)
will be used during seismic acquisition. When not towing seismic survey
gear, the Wecoma cruises at 22.2 km/hour (12 knots) and has a maximum
speed of 26 km/hour (14 knots). It has a normal operating range of
approximately 13,300 km. The Wecoma will also serve as the platform
from which vessel-based Marine Mammal Visual Observers (MMVO) will
watch for animals before and during GI airgun operations.

Acoustic Source Specifications

Seismic Airguns
    During the proposed survey, the Wecoma will tow a single GI airgun,
with a volume of 45 in\3\, and a 300 m long streamer containing
hydrophones along predetermined lines. Seismic pulses will be emitted
at intervals of 10 seconds. At a speed of 6 knots (11.1 km/hour), the
10 second shot spacing corresponds to a shot interval of approximately
31 m (101.7 ft).
    The generator chamber of the GI airgun, the one responsible for
introducing the sound pulse into the ocean, is 45 in\3\. The larger
(105 in\3\) injector chamber injects air into the previously-generated
bubble to maintain its shape, and does not introduce more sound into
the water. The 45 in\3\ GI airgun will be towed 21 m (68.9 ft) behind
the Wecoma at a depth of 4 m (13.1 ft). The sound pressure field of
that GI airgun variation at a tow depth of 2.5 m has been modeled by
Lamont-Doherty Earth Observatory (L-DEO) in relation to distance and
direction for the GI airgun.
    As the GI airgun is towed along the survey line, the towed
hydrophone array in the 300 m streamer receives the reflected signals
and transfers the data on the on-board processing system. Given the
relatively short streamer length behind the vessel, the turning rate of
the vessel while the gear is deployed is much higher than the limit of
five degrees per minute for a seismic vessel towing a streamer of more
typical length (much greater than 1 km). Thus, the maneuverability of
the vessel is not limited much during operations.
    The root mean square (rms) received levels that are used as impact
criteria for marine mammals are not directly comparable to the peak (pk
or 0-pk) or peak-to-peak (pk-pk) values normally used to characterize
source levels of airgun arrays. The measurement units used to describe
airgun sources, peak or peak-to-peak decibels, are always higher than
the ``root mean square'' (rms) decibels referred to in biological
literature. A measured received level of 160 dB re 1 μPa (rms) in
the far field would typically correspond to a peak measurement of
approximately 170 to 172 dB, and to a peak-to-peak measurement of
approximately 176 to 178 dB, as measured for the same pulse received at
the same location (Greene, 1997; McCauley et al., 1998, 2000). The
precise difference between rms and peak or peak-to-peak values depends
on the frequency content and duration of the pulse, among other
factors. However, the rms level is always lower than the peak or peak-
to-peak level for an airgun-type source.
    Received sound levels have been modeled by L-DEO for a number of
airgun configurations, including one 45 in\3\ GI airgun, in relation to
distance from the airgun(s) (see Figure 2 of SIO's application). The
model does not allow for bottom interactions, and is most directly
applicable to deep water. Based on modeling, estimates of the maximum
distances from the GI airgun where sound levels of 190, 180, and 160 dB
re 1 μPa (rms) are predicted to be received in deep (>1,000 m) water
are shown in this Federal Register notice (reprinted from Table 1 of
SIO's application). Because the model results are for a 2.5 m tow
depth, the distances in Table 1 slightly underestimate the distances
for the 45 in\3\ GI airgun towed at 4 m depth.
Sub-bottom Profiler
    Along with the GI airgun operations, one additional acoustical data
acquisition system will be operated throughout the cruise. The ocean
floor will be mapped with a Knudsen Engineering Model 320BR 12 kHz and
3.5 kHz sub-bottom profiler (SBP). Multi-beam sonar will not be used.
    The Knudsen Engineering Model 320BR SBP is a dual-frequency
transceiver designed to operate at 3.5 and/or 12 kHz. It is used to
provide data about the sedimentary features that occur below the sea
floor. The energy from the sub-bottom profiler is directed downward via
a 12 kHz transducer (EDO 323B) or a 3.5 kHz array of 16 ORE 137D
transducers in a 4x4 arrangement. The maximum power output of the 320BR
is 10 kilowatts for the 3.5 kHz section and 2 kilowatts for the 12 kHz section.
    The pulse length for the 3.5 kHz section of the 320 BR is 0.8-24 ms,

[[Page 34717]]

controlled by the system operator in regards to water depth and
reflectivity of the bottom sediments, and will usually be 12 or 24 ms
in this survey. The system produces one sound pulse and then waits for
its return before transmitting again. Thus, the pulse interval is
directly dependent upon water depth, and in this survey is 4.5-8
seconds. Using the Sonar Equations and assuming 100 percent efficiency
in the system (impractical in real world applications), the source
level for the 320BR is calculated to be 211 dB re 1 Pam. In practical
operation, the 3.5 kHz array is seldom driven at more than 80 percent
of maximum, usually less than 50 percent.
Safety Radii
    NMFS has determined that for acoustic effects, using acoustic
thresholds in combination with corresponding safety radii is an
effective way to consistently apply measures to avoid or minimize the
impacts of an action, and to quantitatively estimate the effects of an
action. Thresholds are used in two ways: (1) To establish a mitigation
shut-down or power-down zone, i.e., if an animal enters an area
calculated to be ensonified above the level of an established
threshold, a sound source is powered down or shut down; and (2) to
calculate take, in that a model may be used to calculate the area
around the sound source that will be ensonified to that level or above,
then, based on the estimated density of animals and the distance that
the sound source moves, NMFS can estimate the number of marine mammals
that may be ``taken.''
    As a matter of past practice and based on the best available
information at the time regarding the effects of marine sound compiled
over the past decade, NMFS has used conservative numerical estimates to
approximate where Level A harassment from acoustic sources begins: 180
dB re 1 μPa (rms) level for cetaceans and 190 dB re 1 μPa (rms)
for pinnipeds. A review of the available scientific data using an
application of science-based extrapolation procedures (Southall et al.,
2007) strongly suggests that Level A harassment (as well as TTS) from
single sound exposure impulse events may occur at much higher levels
than the levels previously estimated using very limited data. However,
for purposes of this proposed action, SIO's application sets forth, and
NMFS is using, the more conservative 180 and 190 dB re 1 μPa (rms)
criteria. NMFS also considers 160 dB re 1 μPa (rms) as the criterion
for estimating the onset of Level B harassment from acoustic sources
like impulse sounds used in the seismic survey.
    Empirical data concerning the 180 and 160 dB distances have been
acquired based on measurements during the acoustic verification study
conducted by L-DEO in the northern Gulf of Mexico from May 27 to June
3, 2003 (Tolstoy et al., 2004). Although the results are limited the
data showed that radii around the airguns where the received level
would be 180 dB re 1 μPa (rms), the safety criterion applicable to
cetaceans (NMFS, 2000), vary with water depth. Similar depth-related
variation is likely in the 190 dB distances applicable to pinnipeds.
Correction factors were developed for water depths 100-1,000 m and <100 m.
    The empirical data indicate that, for deep water (>1,000 m), the L-
DEO model tends to overestimate the received sound levels at a given
distance (Tolstoy et al., 2004). However, to be precautionary pending
acquisition of additional empirical data, it is proposed that safety
radii during GI airgun operations in deep water will be values
predicted by L-DEO's model (see Table 1 below). Therefore, the assumed
180 and 190 dB radii are 23 m (75.5 ft) and 8 m (26 ft), respectively.
    Empirical measurements indicated that in shallow water (<100 m),
the L-DEO model underestimates actual levels. In previous L-DEO
projects, the exclusion zones were typically based on measured values
and ranged from 1.3 to 15x higher than the modeled values depending on
the size of the airgun array and the sound level measured (Tolstoy et
al., 2004). During the proposed cruise, similar factors will be applied
to derive appropriate shallow water radii from the modeled deep water
radii for the GI airgun (see Table 1 below).
    Empirical measurements were not conducted for intermediate depths
(100-1,000 m). On the expectation that results will be intermediate
between those from shallow and deep water, a 1.5x correction factor is
applied to the estimates provided by the model for deep water
situations. This is the same factor that was applied to the model
estimates during L-DEO cruises in 2003. The assumed 180 and 190 dB
radii in intermediate depth water are 35 m (115 ft) and 12 m (39.4 ft),
respectively (see Table 1 below).

 Table 1--Predicted distances to Which Sound Levels [gteqt]190, 180, and 160 dB re 1 &mu;Pa Might Be Received in
Shallow (<100 m; 328 ft), Intermediate (100-1,000 m; 328-3,280 ft), and Deep (>1,000 m; 3,280 ft) Water From the
  Single 45 in\3\ GI Airgun Used During the Seismic Surveys in the Northeastern Pacific Ocean During July 2009
                            [Distances are based on model results provided by L-DEO]
----------------------------------------------------------------------------------------------------------------
                                                                            Predicted RMS distances (m)
       Source and volume         Tow depth (m)     Water depth   -----------------------------------------------
                                                                      190 dB          180 dB          160 dB
----------------------------------------------------------------------------------------------------------------
Single GI airgun 45 in\3\.....               4  Deep (>1,000 m).               8              23             220
                                ..............  Intermediate                  12              35             330
                                                 (100-1,000 m).
                                ..............  Shallow (<100 m)              95             150             570
----------------------------------------------------------------------------------------------------------------

Dates, Duration, and Region of Activity

    The Wecoma is scheduled to depart from Newport, Oregon, on July 14,
2009, and to return on July 20, 2009. The GI airgun will be used for
approximately two hours at each of 16 OBS locations. The program will
consist of approximately 7 days of seismic acquisition. The exact dates
of the activities may vary by a few days because of weather conditions,
repositioning, streamer operations, and adjustments, GI airgun
deployment, or the need to repeat some lines if data quality is
substandard. The seismic surveys will take place off the Oregon coast
in the northeastern Pacific Ocean (see Figure 1 of SIO's application).
The overall area within which the seismic surveys will occur is located
between approximately 44[deg] and 45[deg] N. and 124.5[deg] and
126[deg] W. (see Figure 1 of SIO's application). The surveys will take
place in water depths just less than 100 m and to almost 3,000 m, entirely

[[Page 34718]]

within the Exclusive Economic Zone (EEZ) of the U.S.

Comments and Responses

    A notice of receipt of the SIO application and proposed IHA was
published in the Federal Register on May 26, 2009 (74 FR 24799). During
the comment period, NMFS received comments from the Marine Mammal
Commission (Commission). Following are comments from the Commission and
NMFS' responses.
    Comment 1: The Commission recommends that the NMFS issue the
requested authorization provided that the authorization includes all of
the proposed monitoring and mitigation measures to minimize the likelihood
of serious injury to the potentially affected marine mammal species.
    Response: NMFS concurs with the Commission's recommendations and
has included requirements to these effects in the IHA.
    Comment 2: The Commission recommends that the NMFS issue the
requested authorization provided that the NMFS clarify when the use of
night vision devices (NVDs) will be required and provide additional
justification for its implied conclusion that observers will be able to
achieve a high nighttime detection rate.
    Response: NVDs are used at night and during some low-light
conditions. Though it depends on the lights on the ship, the sea state,
and thermal factors, MMVOs estimated that visual detection is effective
out to between 150 and 250 m (492 to 820 ft) using NVDs and about 30 m
(98 ft) with the naked eye. Depending on water depth, the relevant
safety zones for this survey range from 8 m to 150 m (26 to 492 ft)
(see Table 1 above) and NMFS believes that MMVOs are effective at
visually detecting marine mammals within these distances.
    Marine seismic surveys may continue into night and low-light hours
if such segment(s) of the survey is initiated when the entire relevant
safety zones are visible and can be effectively monitored. No
initiation of airgun array operations is permitted from a shut-down
position at night or during low-light hours (such as in dense fog or
heavy rain) when the entire relevant safety zone cannot be effectively
monitored by MMVOs on duty aboard the Wecoma. NMFS has included a
requirement to this effect in the IHA issued to SIO.
    Comment 3: The Commission recommends that the NMFS issue the
requested authorization provided that the authorization requires that
operations be suspended immediately, pending review by the NMFS, 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
the seismic survey.
    Response: NMFS concurs with the Commission's recommendations and
has included a requirement to this effect in the IHA.

Description of Marine Mammals in the Proposed Activity Area

    A total of 32 marine mammal species may occur or have been
documented to occur in the marine waters off Oregon and Washington,
excluding extralimital sightings or strandings (Fiscus and Niggol,
1965; Green et al., 1992, 1993; Barlow, 1997, 2003; Mangels and
Gerrodette, 1994; Von Saunder and Barlow, 1999; Barlow and Taylor,
2001; Buchanan et al., 2001; Calambokidis et al., 2004; Calambokidis
and Barlow, 2004). The species include 19 odontocetes (toothed
cetaceans, such as dolphins), 7 mysticetes (baleen whales), 5
pinnipeds, and sea otters. Six of the species that may occur in the
project area are listed under the Endangered Species Act (ESA) as
Endangered, including sperm, humpback, sei, fin, blue, and North
Pacific right whales. Another species, the Steller sea lion, is listed
as Threatened and may occur in the project area.
    The study area is located approximately 25 to 110 km (15.5 to 68.4
mi) offshore from Oregon over water depths from just less than 100 m to
almost 3,000 m. Two of the 32 species, gray whales and sea otters, are
not expected in the project area because their occurrence off Oregon is
limited to very shallow, coastal waters. Three other species,
California sea lions, Steller sea lions, and harbor seals, are mainly
coastal, and would be rare at most at the OBS locations. Information on
the habitat, abundance, and conservation status of the species that may
occur in the study area is given in Table 2 (below, see Table 2 of
SIO's application). Vagrant ringed seals, hooded seals, and ribbon
seals have been sighted or stranded on the coast of California (see
Mead, 1981; Reeves et al., 2002) and presumably passed through Oregon
waters. A vagrant beluga whale was seen off the coast of Washington
(Reeves et al., 2002). Those seven species are not addressed in detail
in the summaries in SIO's application.
    The six species of marine mammals expected to be most common in the
deep pelagic or slope waters of the project area, where most of the
survey sites are located, include the Pacific white-sided dolphin,
northern right whale dolphin, Risso's dolphin, short beaked common
dolphin, Dall's porpoise, and northern fur seal (Green et al., 1992,
1993; Buchanan et al., 2001; Barlow, 2003; Barlow and Forney, 2007;
Carretta et al., 2007). The fin whale, Dall's porpoise, and the
northern elephant seal were the species sighted most often off Oregon
and Washington during the ORCAWALE 2008 surveys (NMFS, 2008).
    Table 2 below outlines the marine mammal species, their habitat,
abundance, density, and conservation status in the proposed project
area. Additional information regarding the distribution of these
species expected to be found in the project area and how the estimated
densities were calculated was included in the notice of the proposed
IHA (74 FR 24799, May 26, 2009) and may be found in SIO's application.

[[Page 34719]]

 Table 2--The Occurrence, Habitat, Regional Abundance, Best and Maximum Density Estimates, Number of Marine Mammals That Could be Exposed to Sound Level
 at or Above 160dB re 1&mu;Pa, Best Estimate of Number of Individuals Exposed, and Best Estimate of Number of Exposures per Marine Mammal in or Near the
                                         Proposed Low-Energy Seismic Survey Area in the Northeast Pacific Ocean
                                                [See Tables 2-4 in SIO's application for further detail]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                            Percent of
                                                                                           Density/1000    Density/1000      Number of       estimated
               Species                          Habitat            Regional population     km\2\ (best)     km\2\ (max)   indiv. exposed    population
                                                                         size \e\               \b\             \c\         to >=160 dB     exposed to
                                                                                                                                             >=160 dB
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Mysticetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Eastern Pacific gray whale             Coastal.................  17,752.................           NA              NA                  0            0
 (Eschrichtius robustus).
North Pacific right whale (Eubalaena   Pelagic and coastal.....  NA (Probably less than             0               0                  0            0
 japonica).                                                       100) \f\.
Humpback whale (Megaptera              Mainly nearshore waters   1,396..................            0.69            1.50               1            0.07
 novaeangliae).                         and banks.
Minke whale (Balaenoptera              Pelagic and coastal.....  898....................            0.68            1.1                0            0
 acutorostrata).
Sei whale (Balaenoptera borealis)....  Primarily offshore,       43.....................            0.13            0.5                1            2.33
                                        pelagic.
Fin whale (Balaenoptera physalus)....  Continental slope,        3,454..................            0.95            1.3                1            0.03
                                        mostly pelagic.
Blue whale (Balaenoptera musculus)...  Pelagic and coastal.....  1,186..................            0.19            0.4                1            0.08
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       Odontocetes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter macrocephalus).  Usually pelagic and deep  2,265..................            1.39            0.58               1            0.04
                                        seas.
Pygmy sperm whale (Kogia breviceps)..  Deep waters off shelf...  NA.....................            1.24            2.8                1           NA
Dwarf sperm whale (Kogia sima).......  Deep waters off the       NA.....................            0               0                  0            0
                                        shelf.
Cuvier's beaked whale (Ziphius         Pelagic.................  2,171..................            0               0                  0            0
 cavirostris).
Baird's beaked whale (Berardius        Pelagic.................  313....................            1.64            0.60               0            0
 bairdii).
Blainville's beaked whale (Mesoplodon  Slope, offshore.........  1,024 \g\..............            0               0                  0            0
 densirostris).
Hubb's beaked whale (Mesoplodon        Slope, offshore.........  1,024 \g\..............            0               0                  0            0
 carlhubbsi).
Stejneger's beaked whale (Mesoplodon   Slope, offshore.........  1,024 \g\..............            0               0                  0            0
 stejnegeri).
Offshore bottlenose dolphin (Tursiops  Offshore, slope.........  3,257..................            0               0                  0            0
 truncatus).
Striped dolphin (Stenella              Off continental shelf...  23,883.................            0.04            0.1                0            0
 coeruleoalba).
Short-beaked common dolphin            Shelf and pelagic,        487,622................           14.14           35                  4           <0.01
 (Delphinus delphis).                   seamounts.
Pacific white-sided dolphin            Offshore, slope.........  25,233.................           24.84           33.2                6            0.02
 (Lagenorhynchus obliquidens).
Risso's dolphin (Grampus griseus)....  Shelf, slope, seamounts.  12,093.................           12.91           17.3                3            0.02
Northern right whale dolphin           Slope, offshore waters..  15,305.................           19.39           26.7                5            0.03
 (Lissodelphis borealis).
False killer whale (Pseudorca          Pelagic, occasionally     NA.....................            0               0                  0            0
 crassidens).                           inshore.
Killer whale (Orcinus orca)..........  Widely distributed......  422 (Offshore).........            1.62            2.7                0            0
Short-finned pilot whale               Mostly pelagic, high-     245....................            0               0                  0            0
 (Globicephala macrorhynchus).          relief topography.
Harbor porpoise (Phocoena phocoena)..  Coastal and inland        37,745 (OR/WA).........           NA              NA                  0            0
                                        waters.

[[Page 34720]]

Dall's porpoise (Phocoenoides dalli).  Shelf, slope, offshore..  57,549.................          150.17          250.9               39            0.07
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                        Pinnipeds
--------------------------------------------------------------------------------------------------------------------------------------------------------
Northern fur seal (Callorhinus         Pelagic, offshore.......  721,935 \f\............           10             100                  3           <0.01
 ursinus).
California sea lion (Zalophus          Coastal, shelf..........  238,000................           NA              NA                  2           <0.01
 californianus).
Harbor seal (Phoca vitulina            Coastal.................  24,732 (OR/WA).........           13              NA                  1           <0.01
 richardsi).
Steller sea lion (Eumetopias jubatus)  Coastal, shelf..........  48,519 Eastern U.S. \f\           11              NA                  1           <0.01
Northern elephant seal (Mirounga       Coastal, pelagic when     124,000 (CA)...........           20             200                  5            0.01
 angustirostris).                       migrating.
--------------------------------------------------------------------------------------------------------------------------------------------------------
NA--Data not available or species status was not assessed, CA = California, OR = Oregon, WA = Washington.
\a\ U.S. Endangered Species Act: EN = Endangered, T = Threatened, NL = Not listed.
\b\ Best estimate as listed in Table 3 of the application.
\c\ Maximum estimate as listed in Table 3 of the application.
\d\ The numbers of at-sea sightings of California sea lions and northern elephant seals were too small to provide meaningful density estimates (Bonnell
  et al., 1992); density of northern elephant seals was estimated based on sightings during the ORCAWALE 2008 surveys.
\e\ Abundance given for U.S. Eastern North Pacific, or CA/OR/WA stock, whichever is included in the 2007 U.S. Pacific Marine Mammal Stock Assessments
  (Carretta et al., 2007), unless otherwise stated.
\f\ Angliss and Outlaw (2008).
\g\ All mesoplodont whales.

Potential Effects on Marine Mammals

Potential Effects of Airguns

    The effects of sounds from airguns might result in one or more of
the following: Tolerance, masking of natural sounds, behavioral
disturbances, temporary or permanent hearing impairment, and non-
auditory physical or physiological effects (Richardson et al., 1995;
Gordon et al., 2004; Nowacek et al., 2007; Southall et al., 2007).
Permanent hearing impairment, in the unlikely event that it occurred,
would constitute injury, but temporary threshold shift (TTS) is not an
injury (Southall et al., 2007). With the possible exception of some
cases of temporary threshold shift in harbor seals, it is unlikely that
the project would result in any cases of temporary or especially
permanent hearing impairment, or any significant non-auditory physical
or physiological effects. Some behavioral disturbance is expected, but
this would be localized and short-term.
    The notice of the proposed IHA (74 FR 24799, May 26, 2009) included
a discussion of the effects of sounds from airguns on mysticetes,
odontocetes, and pinnipeds, including tolerance, masking, behavioral
disturbance, hearing impairment, and other non-auditory physical
effects. Additional information on the behavioral reactions (or lack
thereof) by all types of marine mammals to seismic vessels can be found
in SIO's application and associated EA.
    The notice of the proposed IHA also included a discussion of the
potential effects of the sub-bottom profiler. Because of the shape of
the beams of these sources and their power, NMFS believes it unlikely
that marine mammals will be exposed to either the sub-bottom profiler
at levels at or above those likely to cause harassment. Further, NMFS
believes that the brief exposure of cetaceans to a few signals from the
sub-bottom profiler sonar system is not likely to result in the
harassment of marine mammals.

Estimated Take by Incidental Harassment

    The notice of the proposed IHA (74 FR 24799, May 26, 2009) included
an in-depth discussion of the methods used to calculate the densities
of the marine mammals in the area of the seismic survey and the take
estimates. Additional information was included in SIO's application. A
summary is included here.
    All anticipated takes would be ``takes by harassment,'' involving
temporary changes in behavior. The monitoring and mitigation measures
are expected to minimize the possibility of injurious takes. (However,
as noted earlier, there is no specific information demonstrating that
injurious ``takes'' would occur even in the absence of the planned
monitoring and mitigation measures.) The sections below describe
methods to estimate ``take by harassment'', and present estimates of
the numbers of marine mammals that might be affected during the
proposed seismic program. The estimates of ``take by harassment'' are
based on (1) data concerning marine mammal densities (numbers per unit
area) obtained during surveys off Oregon and Washington during 1996,
2001, and 2005 (cetaceans), or 1989 to 1990 (pinnipeds) by NMFS
Southwest Fisheries Science Center (SWFSC), and (2) estimates of the
size of the 160 dB isolpeths where takes could potentially occur from
the proposed seismic survey off the coast of Oregon in the northeastern
Pacific Ocean.
    Extensive systematic aircraft and ship-based surveys have been
conducted for marine mammals offshore of Oregon and Washington (Bonnell
et al., 1992; Green et al., 1992, 1993;

[[Page 34721]]

Barlow 1997, 2003; Barlow and Taylor, 2001; Calambokidis and Barlow,
2004; Barlow and Forney in prep.). The most comprehensive and recent
density data available for cetacean species in slope and offshore
waters of Oregon are from the 1996, 2001, and 2005 NMFS SWFSC
``ORCAWALE'' or ``CSCAPE'' ship surveys as synthesized by Barlow and
Forney (2007). The surveys were conducted up to approximately 550 km
(342 mi) offshore from June or July to November or December.
Systematic, offshore, at-sea survey data for pinnipeds are more
limited. The most comprehensive such studies are reported by Bonnell et
al. (1992) based on systematic aerial surveys conducted in 1989-1990.
    Oceanographic conditions, including occasional El Niño and
La Niña events, influence the distribution and numbers of marine
mammals present in the Northeast Pacific Ocean, including Oregon,
resulting in considerable year-to-year variation in the distribution
and abundance of many marine mammal species (Forney and Barlow, 1998;
Buchanan et al., 2001; Escorza-Treviño, 2002; Ferrero et al.,
2002; Philbrick et al., 2003). Thus, for some species the densities
derived from recent surveys may not be representative of the densities
that will be encountered during the proposed seismic survey. For this
IHA application, cruise reports from the ORCAWALE 2008 surveys (NMFS,
2008) were inspected to assess whether there were any observable
changes from the previous surveys of the same area.
    Table 3 of SIO's application (reprinted as Table 2 in this Federal
Register notice) gives the average and maximum densities for each
species of cetacean reported off Oregon and Washington, corrected for
effort, based on the densities reported for the 1996, 2001, and 2005
surveys (Barlow and Forney, 2007). The densities from those studies had
been corrected by the original authors for both detectability bias and
availability bias. Detectability bias is associated with diminishing
sightability with increasing lateral distance from the trackline.
Availability bias refers to the fact that there is <100 percent
probability of sighting an animal that is present along the survey trackline.
    Table 3 of SIO's application (Table 2 in this Federal Register
notice) also includes mean density information for three of the five
pinniped species that occur off Oregon and Washington and mean and
maximum densities for one of those species, from Bonnell et al. (1992).
Densities were not calculated for the other two species because of the
small number of sightings on systematic transect surveys. One of those,
the northern elephant seal, was the dominant seal sighted during the
ORCAWALE 2008 surveys (29 of 33 pinnipeds sighted off Oregon and
Washington), so it was included at a density set at twice that of the
northern fur seal, the other species sighted during the ORCAWALE 2008 surveys.
    It should be noted that the following estimates of ``takes by
harassment'' assume that the surveys will be undertaken and completed;
in fact, the planned number of line kms has been increased by 25
percent to accommodate lines that may need to be repeated, equipment
testing, etc. As is typical on offshore ship surveys, inclement weather
and equipment malfunctions are likely to cause delays and may limit the
number of useful line kms of seismic operations that can be undertaken.
Furthermore, any marine mammal sightings within or near the designated
safety zones will result in the shut-down of seismic operations as a
mitigation measure. Thus, the following estimates of the numbers of
marine mammals potentially exposed to 160 dB are precautionary, and
probably overestimate the actual numbers of marine mammals that might
be involved. These estimates assume that there will be no weather,
equipment, or mitigation delays, which is highly unlikely.
    There is some uncertainty about the representativeness of the data
and the assumption used in the calculations. However, the approach used
is believed to be the best available approach. Also, to provide some
allowance for these uncertainties ``maximum estimates'' as well as
``best estimates'' of the numbers potentially affected have been
derived. Best and maximum estimates are based on the average and
maximum estimates of densities reported primarily by Barlow and Forney
(2007) and Bonnell et al. (1992) described above. The estimated numbers
of potential individuals exposed are presented below based on the 160
dB re 1 &mu;Pa (rms) Level B harassment criterion for all cetaceans and
pinnipeds. It is assumed that a marine mammal exposed to airgun sounds
this strong might change their behavior sufficiently to be considered
``taken by harassment.''
    The number of different individuals that may be exposed to GI
airgun sounds with received levels >=160 dB re 1 &mu;Pa (rms) on one or
more occasions was estimated by considering the total marine area that
would be within the 160 dB radius around the operating airgun array on
at least one occasion. The proposed seismic lines do not run parallel
to each other in close proximity, which minimizes the number of times
an individual mammal may be exposed during the survey. The best
estimates in this section are based on the averages of the densities
from the 1996, 2001, and 2005 NMFS surveys, and maximum estimates are
based on the highest of the three densities. Table 4 of SIO's
application and Table 2 of this Federal Register notice show the best
and maximum estimates of the number of marine mammals that could
potentially be affected during the seismic survey.
    The number of different individuals potentially exposed to received
levels >=160 dB re 1 &mu;Pa (rms) was calculated by multiplying:
    • The expected species density, either ``mean'' (i.e., best
estimate) or ``maximum,'' times; and
    • The area anticipated to be ensonified to that level during
GI airgun operations.
    The area expected to be ensonified was determined by entering the
planned survey lines into a MapInfo Geographic Information System
(GIS), using the GIS to identify the relevant areas by ``drawing'' the
applicable 160 dB buffer around each seismic line (depending on water
and tow depth) and then calculating the total area within the buffers.
Areas where overlap occurred (because of intersecting lines) were
included only once to determine the area expected to be ensonified. In
the proposed survey, there is minimal overlap (5 percent for 160 dB),
so virtually no marine mammal would be ensonified above those
thresholds more than once.
    Applying the approach described above, approximately 208 km\2\
(80.3 mi\2\) would be within the 160 dB isopleth on one or more
occasions during the surveys at all 16 OBS locations. For inshore OBS
locations, approximately 60 km\2\ (23 mi\2\) would be within the 160 dB
isopleths; that area was used for calculations for the pinniped species
that could occur only at those locations. This approach does not allow
for turnover in the mammal populations in the study area during the
course of the surveys. That might underestimate actual numbers of
individuals exposed, although the conservative distances used to
calculate the area may offset this. In addition, the approach assumes
that no cetaceans will move away or toward the trackline as the Wecoma
approaches, in response to increasing sound levels prior to the time
the levels reach 160 dB. Another way of interpreting the estimates that
follow in Table 3 (below) is that they represent the number of
individuals that are expected (in the absence of a seismic program) to
occur in the waters that will be exposed to >=160 dB re 1 &mu;Pa (rms).

[[Page 34722]]

    Table 3 (see below) outlines the species, estimated stock
population (minimum and best), and estimated percentage of the stock
exposed to seismic pulses in the project area. Additional information
regarding the status, abundance, and distribution of the marine mammals
in the area and how densities were calculated was included in Table 2
(see above), the notice of the proposed IHA (74 FR 24799, May 26, 2009)
and may be found in SIO's application.

 Table 3--The Estimates of the Possible Numbers of Marine Mammals Exposed to Sound Levels Greater Than or Equal
to 160 dB During SIO's Proposed Seismic Survey Off Oregon in July 2009. The Proposed Sound Source is a Single GI
  Airgun. Received Levels are Expressed in dB re 1 &mu;Pa (rms) (Averaged Over Pulse Duration), Consistent With
 NMFS' Practice. Not All Marine Mammals Will Change Their Behavior When Exposed to These Sound Levels, But Some
                            May Alter Their Behavior When Levels Are Lower (See Text)
                            [See Tables 2-4 in SIO's application for further detail]
----------------------------------------------------------------------------------------------------------------
                                                                     Number of       Number of       Approx. %
                                                                    individuals     individuals      Regional
                             Species                              exposed (best)   exposed (max)    Population
                                                                        \1\             \1\         (best) \2\
----------------------------------------------------------------------------------------------------------------
                                                   Mysticetes
----------------------------------------------------------------------------------------------------------------
Eastern Pacific gray whale (Eschrichtius robustus)..............               0               0            0
North Pacific right whale (Eubalaena japonica)..................               0               0            0
Humpback whale (Megaptera novaeangliae).........................               1               2            0.07
Minke whale (Balaenoptera acutorostrata)........................               0               0            0
Sei whale (Balaenoptera borealis)...............................               1               0            2.33
Fin whale (Balaenoptera physalus)...............................               1               1            0.03
Blue whale (Balaenoptera musculus)..............................               1               1            0.08
----------------------------------------------------------------------------------------------------------------
                                                   Odontocetes
----------------------------------------------------------------------------------------------------------------
Sperm whale (Physeter macrocephalus)............................               1               8            0.04
Pygmy sperm whale (Kogia breviceps).............................               0               1           NA
Dwarf sperm whale (Kogia sima)..................................               0               0            0
Cuvier's beaked whale (Ziphius cavirostris).....................               0               0            0
Baird's beaked whale (Berardius bairdii)........................               0               1            0
Blainville's beaked whale (Mesoplodon densirostris).............               0               0            0
Hubb's beaked whale (Mesoplodon carlhubbsi).....................               0               0            0
Stejneger's beaked whale (Mesoplodon stejnegeri)................               0               0            0
Mesoplodon sp. (unidentified) \3\...............................               0               1            0
Offshore bottlenose dolphin (Tursiops truncatus)................               0               0            0
Striped dolphin (Stenella coeruleoalba).........................               0               0            0
Short-beaked common dolphin (Delphinus delphis).................               4               9           <0.01
Pacific white-sided dolphin (Lagenorhynchus obliquidens)........               6               9            0.02
Northern right-whale dolphin (Lissodelphis borealis)............               5               7            0.02
Risso's dolphin (Grampus griseus)...............................               3               4            0.03
False killer whale (Pseudorca crassidens).......................               0               0           NA
Killer whale (Orcinus orca).....................................               0               1            0
Short-finned pilot whale (Globicephala macrorhynchus)...........               0               0            0
Harbor porpoise (Phocoena phocoena).............................               0               0            0
Dall's porpoise (Phocoenoides dalli)............................              39              65            0.07
----------------------------------------------------------------------------------------------------------------
                                                    Pinnipeds
----------------------------------------------------------------------------------------------------------------
Northern fur seal (Callorhinus ursinus).........................               3              26           <0.01
California sea lion (Zalophus californianus)....................               2              NA           <0.01
Steller sea lion (Eumetopias jubatus)...........................               1              NA           <0.01
Harbor seal (Phoca vitulina richardsi)..........................               1              NA           <0.01
Northern elephant seal (Mirounga angustirostris)................               5              52            0.01
----------------------------------------------------------------------------------------------------------------
NA--Data not available or species status was not assessed.
\1\ Best estimate and maximum estimate density are from Table 3 of SIO's application.
\2\ Regional population size estimates are from Table 2 (above).

    Table 4 of SIO's application (Table 3 in this Federal Register
notice) shows the best and maximum estimates of the number of exposures
and the number of individual marine mammals that potentially could be
exposed to greater than or equal to 160 dB re 1 &mu;Pa (rms) during the
different legs of the seismic survey if no animals move away from the
survey vessel.
    The ``best'' of the number of individual marine mammals that could
be exposed to seismic sounds with received levels greater than or equal
to 160 dB re 1 &mu;Pa (rms) (but below Level A harassment thresholds)
during the survey is shown in Table 4 of SIO's application and Table 3
(shown above). The maximum estimates have been requested by SIO. The
``best estimate'' total includes 4 baleen whale individuals. These
estimates were derived from the best density estimates calculated for
these species in the area (see Table 4 of SIO's application). In
addition, 1 sperm whale (0.35 percent of

[[Page 34723]]

the regional population) as well as 0 beaked whales (0 percent of the
regional population). Based on the best estimates, most (93 percent) of
the marine mammals potentially exposed are dolphins and porpoises;
short-beaked common, Pacific white-sided, Northern right-whale, Risso's
dolphins and Dall's porpoises are estimated to be the most common
species in the area, with best estimates of 4 (<0.01 percent of the
regional population), 6 (0.02 percent), 5 (0.03 percent), 3 (0.02
percent), and 39 (0.07 percent) exposed to greater than or equal to 160
dB re &mu;Pa (rms), respectively. The remainder of the marine mammals
that may be potentially exposed are pinnipeds; Northern fur, harbor,
and Northern elephant seals, and Steller sea lions are estimated to be
the most common species in the area, with best estimates of 3 (<0.01
percent), 1 (<0.01 percent), 5 (0.01 percent), and 1 (<0.01 percent)
exposed to greater than or equal to 160 dB re &mu;Pa (rms),
respectively. Haul-outs of California sea lions and harbor seals are
known to be located in the Newport, Oregon area. All of these numbers
are considered small relative to the population sizes of the affected
species or stocks.

Potential Effects on Habitat

    A detailed discussion of the potential effects of this action on
marine mammal habitat, including physiological and behavioral effects
on marine fish and invertebrates, was included in the proposed IHA (74
FR 24799, May 26, 2009). Based on the discussion in the proposed IHA
notice and the nature of the activities (limited duration), the
authorized operations are not expected to have any habitat-related
effects that could cause significant or long-term consequences for
individual marine mammals or their populations or stocks. Similarly,
any effects to food resources are expected to be negligible.
    The SIO seismic survey will not result in any permanent impact on
habitats used by marine mammals, or on the food sources they use. The
main impact issue associated with the proposed activity will be
temporarily elevated noise levels and the associated direct effects on
marine mammals, as described above.

Subsistence Activities

    There is no subsistence hunting for marine mammals in the waters
off of the coast of Oregon that implicates MMPA Section 101(a)(5)(D).

Mitigation and Monitoring

    Mitigation and monitoring measures for the seismic survey have been
developed and refined during previous SIO and NSF-funded seismic
studies and associated environmental assessments (EAs), IHA
applications, and IHAs. The mitigation and monitoring measures
described herein represent a combination of procedures required by past
IHAs for other similar projects and recommended best practices in
Richardson et al. (1995), Pierson et al. (1998), and Weir and Dolman
(2007). The measures are described in detail below.
    Mitigation measures that will be adopted during the proposed survey include:
    (1) Speed or course alteration, provided that doing so will not
compromise operational safety requirements;
    (2) GI airgun shut-down procedures;
    (3) Special procedures for situations or species of particular
concern, e.g., emergency shut-down procedures for North Pacific right
whales, avoidance of concentrations of beaked whales (if visually
sighted), and minimization of approaches to slopes, if possible, to
avoid beaked whale habitat; and
    (4) Additional mitigation measures (see ``additional mitigation
measures'' below).
    Two other common mitigation measures, airgun array power-down and
airgun array ramp-up, are not possible because only one, low-volume GI
airgun will be used for the surveys. The thresholds for estimating
Level A harassment take are also used in connection with proposed mitigation.

Vessel-Based Visual Monitoring

    Marine Mammal Visual Observers (MMVOs) will be based aboard the
seismic source vessel and will watch for marine mammals near the vessel
during daytime airgun operations and during start-ups of airguns at
night. MMVOs will also watch for marine mammals near the seismic vessel
for at least 30 minutes prior to the start of airgun operations and
after an extended shut down of the airguns. When feasible MMVOs will
also make observations during daytime periods when the seismic system
is not operating for comparison of sighting rates and animal behavior
with vs. without airgun operations. Based on MMVO observations, the GI
airgun will be shut down (see below) when marine mammals are detected
within or about to enter a designated EZ that corresponds to the 180 or
190 dB re 1 &mu;Pa (rms) isopleths, depending on whether the animal is
a cetacean or a pinniped. The MMVOs will continue to maintain watch to
determine when the animal(s) are outside the EZ, and airgun operations
will not resume until the animal has left that EZ. The predicted
distances for the 180 and 190 dB EZs are listed according to the water
depth in Table 1 above.
    During seismic operations off of the coast of Oregon, at least two
MMVOs will be based aboard the Wecoma. MMVOs will be appointed by SIO
with NMFS concurrence. At least one MMVO will monitor the EZ for marine
mammals during ongoing daytime GI airgun operations and nighttime
startups of the airguns. MMVO(s) will be on duty in shifts no longer
than 4 hours duration. The vessel crew will also be instructed to
assist in detecting marine mammals and implementing mitigation measures
(if practical). Before the start of the seismic survey the crew will be
given additional instruction regarding how to do so.
    The Wecoma is a suitable platform for marine mammal observations.
Observing stations will be on the bridge wings, with observers' eyes
approximately 6.5 m (21.3 ft) above the waterline and a 180 degree view
outboard from either side, on the whaleback deck in front of the
bridge, with observers' eyes approximately 7 m (23 ft) above the
waterline and approximately 200 degrees view forward, and on the aft
control station, with observer's eyes approximately 5.5 m (18 ft) above
the waterline and a approximately 180 degree view aft that includes the
40 m (131 ft) (180 dB) radius area around the GI airgun. The eyes of
the bridge watch will be at a height of approximately 6.5 m; MMOs will
move to the enclosed bridge during any inclement weather.
    During the daytime, the MMVO(s) will scan the area around the
vessel systematically with reticle binoculars (e.g., 7x50), Big-eye
binoculars (25x150), optical range finders, and with the naked eye.
During darkness, night vision devices will be available, when required.
The MMVOs will be in wireless communication with ship's officers on the
bridge and scientists in the vessel's operations laboratory, so they can
advise promptly of the need for avoidance maneuvers or GI airgun shut down.
    Speed or Course Alteration--If a marine mammal is detected outside
the EZ but is likely to enter based on its position and the relative
movement of the vessel and animal, and if safety and scientific
objectives allow, the vessel speed and/or course may be adjusted to
minimize the likelihood of the animal entering the EZ. Typically,
during seismic operations, major course and speed adjustments are often
impractical when towing long seismic streamers and

[[Page 34724]]

large source arrays, but are possible in this case because only one GI
airgun and a short streamer will be used.
    Shut-down Procedures--The operating airguns(s) will be shut-down if
a marine mammal is detected within or approaching the EZ for the single
GI airgun source. Following a shut-down, GI airgun activity will not
resume until the marine mammal is outside the EZ for the full array.
The animal will be considered to have cleared the EZ if it:
    • Is visually observed to have left the EZ;
    • Has not been seen within the EZ for 15 min in the case of
species with shorter dive durations--small odontocetes (i.e., dolphins)
and pinnipeds; and
    • Has not been seen within the EZ for 30 min in the case of
species with longer dive durations--mysticetes and large odontocetes
(i.e., sperm, pygmy sperm, dwarf sperm, killer, and beaked whales).
    Procedures for Situations or Species of Particular Concern--Special
mitigation procedures will be used for certain situations and species
as follows:
    (1) The GI airgun will be shut-down if a North Pacific right whale
is sighted at any distance from the vessel;
    (2) To avoid beaked whale habitat, approach to slopes will be
minimized, if possible, during the proposed survey. Avoidance of airgun
operations over or near submarine canyons has become a standard
mitigation measure, but there are none within or near the study area.
Four of the 16 OBS locations are on the continental slope, but the GI
airgun is low volume and it will operate only for a short time
(approximately 2 hours at each location).
    (3) If visually sighted, avoidance of concentrations of beaked whales.

Additional Mitigation Measures

    (1) To the maximum extent practicable, SIO will schedule seismic
operations in inshore or shallow waters during daylight hours, and OBS
operations during nighttime hours.
    SIO and NSF will coordinate the planned marine mammal monitoring
program associated with the seismic survey off the coast of Oregon with
applicable U.S. agencies (e.g., NMFS), and will comply with their requirements.

Reporting

MMVO Data and Documentation

    MMVOs will record data to estimate the numbers of marine mammals
exposed to various received sound levels and to document apparent
disturbance reactions or lack thereof. Data will be used to estimate
numbers of animals potentially `taken' by harassment (as defined in the
MMPA). They will also provide information needed to order a shutdown of
the seismic source when a marine mammal or sea turtle is within or near the EZ.
    When a sighting is made, the following information about the
sighting will be recorded:
    (1) Species, group size, and age/size/sex categories (if
determinable); behavior when first sighted and after initial sighting;
heading (if consistent), bearing, and distance from seismic vessel;
sighting cue; apparent reaction to the seismic source or vessel (e.g.,
none, avoidance, approach, paralleling, etc.); and behavioral pace.
    (2) Time, location, heading, speed, activity of the vessel, sea
state, visibility, cloud cover, and sun glare.
    The data listed (time, location, etc.) will 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.
    All observations, as well as information regarding seismic source
shut-down, will be recorded in a standardized format. Data accuracy
will be verified by the MMVOs at sea, and preliminary reports will be
prepared during the field program and summaries forwarded to the
operating institution's shore facility and to NSF weekly or more
frequently. MMVO observations will provide the following information:
    (1) The basis for decisions about shutting down airgun arrays.
    (2) Information needed to estimate the number of marine mammals
potentially `taken by harassment.' These data will be reported to NMFS.
    (3) Data on the occurrence, distribution, and activities of marine
mammals in the area where the seismic study is conducted.
    (4) Data on the behavior and movement patterns of marine mammals
seen at times with and without seismic activity.
    A report will be submitted to NMFS within 90 days after the end of
the cruise. The report will describe the operations that were conducted
and sightings of marine mammals near the operations. The report will be
submitted to NMFS, providing full documentation of methods, results,
and interpretation pertaining to all monitoring. The 90-day report will
summarize the dates and locations of seismic operations, and all marine
mammal sightings (dates, times, locations, activities, associated
seismic survey activities). The report will also include estimates of
the amount and nature of potential ``take'' of marine mammals by
harassment or in other ways.
    All injured or dead marine mammals (regardless of cause) will be
reported to NMFS as soon as practicable. The report should include
species or description of animal, condition of animal, location, time
first found, observed behaviors (if alive) and photo or video, if available.

Endangered Species Act (ESA)

    Pursuant to Section 7 of the ESA, NSF has consulted with the NMFS,
Office of Protected Resources, Endangered Species Division on this
seismic survey. NMFS has also consulted internally pursuant to Section
7 of the ESA on the issuance of an IHA under section 101(a)(5)(D) of
the MMPA for this activity. On July 13, 2009, NMFS concluded
consultation with NMFS and NSF, and issued a Biological Opinion (BiOp),
which concluded that the proposed action and issuance of an IHA are not
likely to jeopardize the continued existence of North Pacific right,
blue, fin, sei, humpback, and sperm whales, and leatherback
(Dermochelys coriacea), green (Chelonia mydas), loggerhead (Caretta
caretta), hawksbill (Eretmochelys imbricate), and olive ridley
(Lepidochelys olivacea) sea turtles. The BiOp also concluded that
designated critical habitat for these species does not occur in the
action area and would not be affected by the survey. Relevant Terms and
Conditions of the Incidental Take Statement in the BiOp have been
incorporated into the IHA.

National Environmental Policy Act (NEPA)

    NSF prepared an Environmental Assessment titled ``Marine Seismic
Survey in the Northeast Pacific, July 2009.'' NSF's draft EA
incorporates an ``Environmental Assessment (EA) of a Planned Low-Energy
Marine Seismic Survey by the Scripps Institution of Oceanography in the
Northeast Pacific Ocean, July 2009,'' prepared by LGL Limited,
Environmental Research Associates, on behalf of NSF and SIO. NMFS
adopted NSF's EA and prepared a Finding of No Significant Impact on the
issuance of the IHA.

Determinations

    NMFS has determined that the impact of conducting the low-energy
marine seismic survey in the Northeast Pacific Ocean may result, at
worst, in a temporary modification in behavior (Level B harassment) of
small numbers of marine mammals. Further, this activity is expected to
result in a negligible impact on the affected species or stocks. The
provision requiring that the activity not have an unmitigable

[[Page 34725]]

impact on the availability of the affected species or stock for
subsistence uses is not implicated for this action.
    For reasons stated previously in this document, the negligible
impact determination is supported by:
    (1) The likelihood that, given sufficient ``notice'' through
relatively slow ship speed, marine mammals are expected to move away
from a noise source that is annoying prior to its becoming potentially
injurious;
    (2) The fact that cetaceans would have to be closer than 23 m (75
ft) in deep water, 35 m (115 ft) in intermediate depths, and 150 m (492
ft) in shallow water when the GI airgun is in use from the vessel to be
exposed to levels of sound (180 dB) believed to have even a minimal
chance of causing PTS;
    (3) The fact that pinnipeds would have to be closer than 8 m (26
ft) in deep water, 12 m (39 ft) in intermediate depths, and 95 m (312
ft) in shallow water when the GI airgun is in use from the vessel to be
exposed to levels of sound (190 dB) believed to have even a minimal
chance of causing PTS;
    (4) The fact that marine mammals would have to be closer than 220 m
(ft) in deep water, 330 m at intermediate depths, and 570 m (ft) in
shallow water when the GI airgun is in use from the vessel to be
exposed to levels of sound (160 dB) believed to have even a minimal
chance at causing TTS; and
    (5) The likelihood that marine mammal detection ability by trained
observers is high at that short distance from the vessel, enabling the
implementation of shut-downs to avoid injury, serious injury, or
mortality. As a result, no take by injury or death is anticipated, and
the potential for temporary or permanent hearing impairment is very low
and will be avoided through the incorporation of the proposed
mitigation measures.
    While the number of marine mammals potentially incidentally
harassed will depend on the distribution and abundance of marine
mammals in the vicinity of the survey activity, the number of potential
harassment takings is estimated to be small, less than one percent of
any of the estimated population sizes, and has been mitigated to the
lowest level practicable through incorporation of the measures
mentioned previously in this document.

Authorization

    As a result of these determinations, NMFS issued an IHA to SIO for
conducting a low-energy marine seismic survey in the Northeast Pacific
Ocean in July, 2009, including the previously mentioned mitigation,
monitoring, and reporting requirements.

    Dated: July 13, 2009.
James H. Lecky,
Director, Office of Protected Resources, National Marine Fisheries Service.
[FR Doc. E9-17067 Filed 7-16-09; 8:45 am]
BILLING CODE 3510-22-P

 
 


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