[Federal Register Volume 68, Number 206 (Friday, October 24, 2003)]
[Notices]
[Pages 60916-60921]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-26929]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[I.D. 073003D]


Taking Marine Mammals Incidental to Specified Activities; 
Oceanographic Surveys in the Eastern Tropical Pacific Ocean

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

ACTION: Notice of issuance of an incidental harassment 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 small numbers of marine mammals, 
by harassment, incidental to conducting oceanographic surveys in the 
Eastern Tropical Pacific Ocean (ETP), has been issues to the Scripps 
Institution of Oceanography (SIO).

DATES: Effective from September 27, 2003, through September 26, 2004.

ADDRESSES: The application, a list of references used in this document, 
and the IHA are available by writing to the Acting Chief, Marine Mammal 
Conservation 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.

FOR FURTHER INFORMATION CONTACT: Sarah C. Hagedorn, Office of Protected 
Resources, NMFS, (301) 713-2322, ext 117.

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.
    Permission may 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 subsistence uses and that the permissible methods of 
taking and requirements pertaining to the 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.''
    Subsection 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. Under section 3(18)(A), 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; 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.
    The term ``Level A harassment'' means harassment described in 
subparagraph (A)(i). The term ``Level B harassment'' means harassment 
described in subparagraph (A)(ii).
    Subsection 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 June 16, 2003, NMFS received an application from SIO for the 
taking, by harassment, of several species of marine mammals incidental 
to conducting a seismic survey program in international waters of the 
ETP and in the Exclusive Economic Zones (EEZ) of several coastal states 
(Mexico, Costa Rica, Panama, Columbia, Ecuador, and Peru), from which 
permission to conduct this type of scientific research has been 
requested. SIO's R/V Roger Revelle is scheduled to undertake a 
multidisciplinary research cruise, including some seismic reflection 
profiling and echo-sounding studies, in the ETP from September 2003 to 
February 2004, primarily 100-400 nautical miles (nm) (185 - 741 km) 
west of northern Peru and 200-1000 nm (370 - 1852 km) west of the 
Galapagos Islands. None of these operations would be in U.S. 
territorial waters or in the U.S. EEZ. A low-energy seismic reflection 
profiler with a small airgun sound source will be used on 3 of the 8 
legs of the cruise. The purpose of this survey is to study the shape 
and structure of the sediment-buried oceanic crust in this part of the 
ETP.

Description of the Activity

    SIO's seismic surveys will involve one vessel, the R/V Roger 
Revelle (under a cooperative agreement with the U.S. Navy, owner of the 
vessel). The Roger Revelle will deploy two airguns as an energy source, 
plus a single short (300 m or 984 ft) towed streamer of hydrophones to 
receive the returning acoustic signals, that can be retrieved and 
deployed in less than 20 minutes.
    The bubble-generating chambers of the two small General-Injector 
(GI) airguns have a combined volume of 90 cubic inches (1475 cubic 
centimeters (cc)), contrasting with 3000-9000 cubic inches (49,161-
147,484 cc) of the large gun arrays typical of academic and commercial 
seismic surveys. The primary seismic pulse is produced by a 45-in\3\ 
(737 cc) generator chamber, while compressed air from a 105-in\3\ (1721 
cc) injector chamber is used to maintain the shape of the bubble and 
reduce its sound-making oscillation. The pair of simultaneously fired 
airguns would have a peak-to-peak (p-p) amplitude of 236 dB re 1 
microPa. In addition, a hull-mounted mid-frequency

[[Page 60917]]

multibeam echo-sounder sonar for seafloor mapping will be routinely 
operated whenever the Revelle is underway. The Kongsberg-Simard EM-120 
sonar images the seafloor over a 120-140 degree-wide swath (about 10-20 
km, or 5-10 nm wide), using very short (15 msec) transmit pulses with a 
10-20 second repetition rate and a 11.25-12.60 kHz frequency sweep. 
Source level in deep water is 240 dB root-mean-squared (rms), but the 
brevity, directivity, and narrow beam-width (1 degree fore-and-aft) of 
the transmit pulses make it unlikely that operation of this depth sonar 
will affect marine mammals.
    None of the 3 research legs for which an IHA is requested will be a 
dedicated seismic reflection survey of the sort typically conducted by 
a specialized seismic vessel. The seismic reflection profiler will be 
used as just one tool in integrated marine geology and geophysical 
studies that also employ bathymetric echo-sounders, passive geophysical 
sensors (such as a gravimeter and magnetometer), and geologic sampling 
tools (like rock dredges and cores). Typical operating procedure during 
these three legs of the cruise will be to conduct seismic profiling, at 
a ship speed of 9-11 knots for periods of 8-12 hours, interspersed with 
episodes of geologic sampling and periods of faster steaming with no 
profiling system deployed. In a few instances (1-3 per leg), longer 
profiles will need to be collected, requiring up to 36 hours of 
continuous airgun operation. The objective is not to image deep crustal 
structureor the stratigraphy of thick sedimentary units (the typical 
goals of seismic surveys); instead the purpose is to measure the 
varying thickness of the 100-400 m-thick (328-1312 ft) cover of pelagic 
sediment that buries and obscures the igneous oceanic crust in the 
study areas, because establishing the relief of the buried crust is 
essential for interpreting the bathymetric, magnetic and gravity data. 
For this limited objective, the large powerful sound sources and 
hydrophone streamers several kilometers long that typify dedicated 
seismic surveys are not required. Nor will any broad ocean volume be 
ensonified by profiling on closely-spaced seismic lines.
    Leg 1 of the cruise, from San Diego to Puerto Caldera, Costa Rica, 
is planned for September 27 - October 9, 2003. This will be primarily a 
staging and instrument testing and calibration leg, but with 2 days of 
seismic reflection profiling and rock-dredging 40-80 nm (74-148 km) off 
the coast of Costa Rica. In addition to the approximately 24 hours of 
seismic profiling, SIO also plans to test and calibrate new components 
of the system, and train shipboard technicians in their use, with 2 or 
3 12-18 hour test runs along parts of the transit track. Because these 
test profiles may obtain scientifically useful data, specific sites 
that are of interest to Mexican researchers have been targeted, in 
partial fulfillment of SIO's foreign-clearance obligation to collect 
data of value to coastal states.
    Leg 2, from Puerto Caldera, Costa Rica, to Manta, Ecuador, is 
planned for October 10 - November 6, 2003. The plan for this leg is to 
(i) conduct a 2-day seismic reflection plus rock dredging survey of 
Cobia Ridge, south of Panama, (ii) collect a north-south seismic 
reflection plus magnetics profile across the eastern Panama Basin, and 
(iii) conduct a 14-day seismic reflection plus bathymetry plus rock 
dredging survey off northern Peru. A total of 200-250 hours of seismic 
reflection profiling is anticipated for this leg of the cruise.
    Leg 5, from Callao, Peru, to Puerto Caldera, Costa Rica, is planned 
to take place from December 28, 2003 - February 23, 2004. Primary 
survey tools will be a multibeam echo-sounder and a new magnetometer 
system. Seismic reflection profiling will have a subsidiary role, 
imaging the relief of the igneous crust in the approximately 20 percent 
of the survey area that has a significant cover of structure-obscuring 
sediment. A total of 150-200 hours of profiling is anticipated for this 
leg of the cruise. All three legs will use the same bathymetric sonar 
and seismic profiling system, described above.
    All planned geophysical data acquisition activities are funded by 
the National Science Foundation (NSF) and will be conducted by SIO 
scientists, with a specific Principal Investigator aboard the vessel. 
Additional information on the airgun array and bathymetric multibeam 
sonar is contained in the application, which is available upon request 
(see ADDRESSES).

Comments and Responses

    A notice of receipt of the Scripps' application and proposed IHA 
was published in the Federal Register on August 25, 2003 (68 FR 51240). 
During the 30-day public comment period, comments were received from 
the Marine Mammal Commission (Commission) and the Center for Biological 
Diversity (CBD).
    Comment 1: The Marine Mammal Commission (the Commission) believes 
that NMFS' preliminary determinations are reasonable, provided NMFS is 
satisfied that the proposed mitigation and monitoring activities are 
adequate to detect marine mammals in the vicinity of the proposed 
operations and ensure that marine mammals are not being taken in 
unanticipated ways or numbers. In this regard, NMFS' Federal Register 
notice states that ``[b]ecause of the ineffectiveness of mammal 
observers during darkness (even though the vessel is equipped with 
night-vision binoculars), seismic reflection profiling will be 
concentrated during daylight hours [but that on] 1-3 
occasions....limited night profiling is needed to allow completion of 
the marine geophysical research.'' However, it remains unclear that, 
for nighttime activities, the monitoring effort will be sufficient to 
determine that no marine mammals are within or about to enter the 
safety zone.
    Response: Because the SIO's scientific research cruise is multi-
disciplinary, and because the seismic research is fairly short-term, 
SIO does not propose to use the 2-GI airgun array during nighttime. If 
a seismic trackline has not been completed, that work will continue 
provided observers are able to see the entire safety zone. However, 
because the size of the airgun array to be used is small, and because 
the safety zones are relatively small, it is unlikely that mammals will 
be within the appropriate safety zones whenever the airguns are on, 
either in daylight or nighttime.
    Comment 2: The NMFS' Federal Register notice states that 
``[o]perations would not resume until the animal is observed outside 
the safety radius or until a minimum of 15 minutes has elapsed since 
the last sighting.'' The Commission notes, however, that beaked and 
sperm whales can dive for much longer than 15 minutes and, thus, could 
be directly below the sound source when it is reactivated.
    Response: The NMFS concurs with the Commission on this point. SIO 
will not proceed with powering up the 2 GI-airgun array unless the 
entire safety radius is visible and no marine mammals are detected 
within the appropriate safety zones; or until 15 minutes (for small 
odontocetes and pinnipeds) or 30 minutes (for mysticetes/large 
odontocetes) after there has been no further visual detection of the 
mammal(s) within the safety zone and the trained marine mammal observer 
on duty is confident that no marine mammals or sea turtles remain 
within the appropriate safety zone. As added mitigation, SIO will 
follow standard ramp-up procedures (see Mitigation below). Also, while 
some whale species may dive for up to 45 minutes, it is unlikely that 
the ship's bridge personel (who are always on watch) would miss a large 
whale

[[Page 60918]]

surfacing from its previous dive if it is within a mile or two of the 
vessel.
    Comment 3: The Commission notes that it is unclear whether vessel-
based passive acoustic monitoring will be conducted as an adjunct to 
visual monitoring during daytime and particularly during nighttime 
operations to detect, locate, and identify marine mammals, and, if not, 
why not.
    Response: Passive acoustical monitoring equipment similar to that 
onboard the R/V Maurice Ewing during the 2003 Gulf of Mexico (GOM) 
Sperm Whale Seismic Study (SWSS), is not the property of SIO or the 
Revelle, and therefore is not available for the ETP cruise. In 
addition, the expense and logistics involved in operating passive 
acoustical monitoring as a mitigation measure (requiring triangulation 
on the vocalization), the fact that the zone where Level A harassment 
could occur is small (738 ft, 225 m), and no nighttime acoustics are 
planned during this cruise, indicate that use of passive acoustical 
monitoring is neither warranted nor practical. The Lamont-Doherty Earth 
Observatory (LDEO) is presently evaluating the scientific results of 
the passive sonar from the SWSS trip to determine whether it is 
practical to incorporate it into future seismic research cruises using 
large airgun arrays. NMFS expects a report on this analysis shortly.
    Comment 4: With respect to pinnipeds, the CBD states that NMFS 
neglects to state the number that the SIO project will take. Instead, 
the proposed authorization notes that SIO ``did not estimate numbers of 
pinnipeds potentially vulnerable to harassment due to insufficient data 
on distribution, abundance, and pinniped response,'' and nonetheless 
concludes that the Revelle is unlikely to encounter significant numbers 
of pinnipeds (68 FR 51242). Practical considerations or unavailability 
of information is no excuse for failing to make the required MMPA 
findings. The proper course of action in the absence of sufficient data 
to make the required MMPA findings and ensure compliance with the MMPA 
is to deny authorization of the project.
    Response: The application contains references of known studies on 
pinniped abundances in the ETP. Insufficient data on distribution, 
abundance, and pinniped response makes it impossible to estimate an 
actual number of pinnipeds potentially vulnerable to harassment. 
However, based on data from these studies, general information exists 
on locations and seasons in which these pinniped species have been 
observed in the past. Because of these estimated species ranges and the 
near-shore nature of many species of pinnipeds, very few, if any, 
pinnipeds are expected to be encountered along the well-offshore 
seismic lines proposed by Scripps. Mitigation measures, the downwards 
directional nature of the low-volume airguns, the brevity of seismic 
profiling in certain habitats, and the fact that many pinnipeds have 
been shown to be highly tolerant of high levels of airgun noise, make 
it even less likely that any pinnipeds encountered will experience 
harassment.
    Comment 5: With respect to cetaceans, the proposed authorization 
does not provide actual numbers taken, but rather states that the total 
estimated take by harassment will be less than 1 percent of most 
cetaceans (including the endangered sperm and blue whales), 1.8 percent 
of pygmy sperm whales, 6.2 percent of dwarf sperm whales, and 1.8 
percent of the endangered humpback whales in the area (68 FR 51243). By 
dismissing the number of cetaceans affected by the proposed activity 
with this reasoning, NMFS has improperly conflated its two, distinct 
statutory obligations to only authorize take of (1) of small numbers; 
and (2) with no more than a negligible impact.
    Response: The SIO application, available by request (see 
ADDRESSES), contains both numbers and percentages of estimated takes. 
Based on the analysis found in this document and in SIO's application, 
which NMFS believes is based on the best scientific information 
available, the notice of proposed authorization (68 FR 51240) used 
percentages to show that even in cases where the absolute numbers may 
not seem ``small'', they are small relative to the size of the affected 
species or stocks. As the SIO application indicates, the absolute 
numbers of takes by species ranges from 1 animal to 21,450.
    Comment 6: While the proposed authorization does outline several 
monitoring, mitigation, and reporting measures, these measures do not 
insure the ``least practicable adverse impact'' as required by the 
MMPA. In addition, NMFS provides no explanation for why seismic 
profiling cannot be limited to daylight hours when observers are on 
surveillance duty and marine mammals are far more detectable. 
Furthermore, under the proposed authorization's shut-down procedures, 
it is unclear why NMFS only addressed measures necessary to avoid Level 
A and not Level B harassment when both are prohibited by the MMPA. 
Also, NMFS failed to mention or require any exclusion zones to avoid 
seismic operations in coastal areas and key habitat for feeding, 
mating, breeding and migration.
    Response: NMFS is requiring SIO to incorporate the mitigation 
measures that are standard for significantly larger seismic arrays. SIO 
may need to continue its operations into night-time hours. Limiting 
activities to daylight hours only would require the Roger Revelle to 
return to the site during daylight, approach the area for which data is 
lacking, and begin seismic activities once again. Since this area could 
not be located exactly, additional seismic operations would need to be 
conducted. This would result in additional noise in the environment and 
is not cost-effective (ship operations are approximately $35,000/day). 
Therefore, the IHA authorizes Scripps to continue seismic into night-
time hours. However, if the array is shut-down at night, seismic 
operations may not begin again until daylight allows the safety zone to 
be observed for the time period noted in this document.
    For similar reasons, shutting down seismic operations to protect 
marine mammals from Level B disturbance, if protracted, would also 
require the Roger Revelle to return to the site again to re-shoot the 
seismic lines. It should be understood that ramp-up and the ship's 
forward speed both allow marine mammals to be exposed to sounds at low 
levels and thereby move out of the area of annoyance, further limiting 
Level B harassment. For those reasons, NMFS prefers to limit the amount 
of noise projected into the water and believes that this suggested 
mitigation measures are not practicable.
    Comment 7: The CBD believes that NMFS determining that a 
Categorical Exclusion is not appropriate for this action and that use 
of another Environmental Assessment (EA) for this action is not 
sufficient.
    Response: NMFS followed NOAA Administrative Order (NAO) 216-6 
before making a determination that this action qualifies for a 
Categorical Exclusion. As noted in the proposed authorization notice 
and this document, an Environmental Assessment (EA) on a similar (i.e., 
oceanographic research) seismic survey action for this area of the 
Pacific Ocean was prepared and released to the public on July 11, 2003 
(68 FR 41314) for a 30-day public comment period. The seismic airgun
    array used in that survey and addressed in the EA was for an array 
of up to 12-airguns with a total volume of 3,721 in\3\. No comments 
were received during that period on the subject EA, and NMFS' analysis 
of that action resulted in a Finding of No Significant Impact 
(FONSI)(see 68 FR 41314, July

[[Page 60919]]

11, 2003). One of the alternatives addressed in that EA was for 
alternative seasons of the year, which would include the time of the 
subject SIO survey. In addition, the acoustic survey described in this 
document by SIO will use acoustic instruments that are significantly 
less intense (total volume of 90 in3) and will therefore have a 
significantly lower impact on the marine environment than acoustic 
sources used by the R/V Maurice Ewing addressed in the EA. Furthermore, 
under NAO 216-6, this is an action of limited size or magnitude. 
Therefore, based on that EA, and a review of the information contained 
in the IHA application from Scripps, NMFS determined that this action 
will not have a significant effect, individually or cumulatively, on 
the human environment. Accordingly, the action is categorically 
excluded from the need to prepare another EA or environmental impact 
statement. A copy of the categorical exclusion documentation has been 
sent to the CBD as requested.
    Comment 8: Direct impacts of SIO's project on the environment 
include but are not limited to its effects on marine mammals, fish 
species, and other sea creatures, such as the giant squid, an important 
food source for sperm whales that has recently suffered injury linked 
to acoustic testing. NMFS has failed to assess the cumulative impacts 
of SIO's project in conjunction with other actions on the environment. 
A proper cumulative impacts analysis in this case should include past, 
present, and reasonably forseeable seismic and other actions in the 
area.
    Response: The EA relied upon here describes impacts, both 
individual and cumulative on marine mammals, sea turtles, and other 
marine life. Scientific information providing a link between low 
frequency seismic research and squid is limited (see McCauley et al., 
2000). A recent news-wire article noting the possible linkage between 
Spanish naval exercises and a stranding of several large squid does not 
establish a causal link until (or if) necropsies can be conducted on 
those animals.

Mitigation

    For the proposed seismic operations in the ETP, SIO will use 2-GI 
guns with a total volume of 90 in3 (1475 cc). These airguns will be 
spread out horizontally, so that the energy from the array will be 
directed mostly downward. The following mitigation measures, as well as 
marine mammal monitoring, will be adopted during the proposed ETP 
seismic survey program.

Safety Radii

    SIO has adopted conservative methods in defining safety zone 
calculations using (i) a 9-dB difference between peak-to-peak (p-p) and 
rms, and (ii) spherical spreading of the sound, even though it is clear 
that at the low acoustic frequencies which dominate SIO's airgun 
output, the generated sound pulses have considerable directivity, 
favoring downward propagation over horizontal propagation. This is 
because in the near-horizontal direction the direct gun pulse is 
closely followed by the opposite-phased bounce off the sea surface, if 
the source is within an acoustic wavelength of the surface. This effect 
can reduce the effective near-horizontal output by as much as 10 dB. 
Because the actual seismic source is a distributed sound source rather 
than a single point source, the highest sound levels measurable at any 
location in the water will be less than the nominal source level.
    The pair of simultaneously fired airguns would have a p-p amplitude 
of 236 dB re 1 microPa. Converting to rms using the 9 dB difference 
between p-p and rms for a sine wave yields an output level of 227 dB 
rms. Therefore, SIO's modeled results for the 2-gun array indicate 
that, assuming spherical spreading, the paired guns would produce sound 
levels of 180 dB re 1 microPa (rms) at a range of about 225 m (738 ft); 
i.e., the radius around the 2-gun array where the received level would 
be 180 dB re 1 microPa (rms), is estimated to be 225 m (738 ft). The 
effect of using a conservative calculation, which yields this safety 
zone for 180 dB rms sound, is to build a safety factor into the airgun 
shut-down radius; this is desirable because mammals may not be observed 
while submerged, and might move towards the acoustic sources during 
dives.

Shutdown Procedures

    SIO proposes to shut down seismic sources whenever marine mammals 
are observed close enough to the vessel that they are at risk of 
exposure to sound levels greater than 180 dB (rms), where there is a 
possibility of Level A harassment. Airgun operations will be suspended 
immediately when marine mammals are observed within, or about to enter, 
this designated safety zone.

Ramp-up Procedures

    SIO will not proceed with powering up the seismic airgun array 
unless the safety zone is visible and no marine mammals are detected 
within the appropriate safety zones or until 15 minutes (for small 
odontocetes and pinnipeds) or 30 minutes (for mysticetes/large 
odontocetes) after there has been no further visual detection of the 
mammal(s) within the safety zone and the trained marine mammal observer 
on duty is confident that no marine mammals or sea turtles remain 
within the appropriate safety zone. Once the safety zone is clear of 
marine mammals, the observer will advise that seismic surveys can re-
commence.
    A standard ``ramp-up'' (soft start) procedure will be followed when 
the airgun array begins operating after a period without any airgun 
operations as specified in this paragraph. From shut-down, ramp-up will 
commence such that the source level of the array will increase in steps 
not exceeding approximately 6 dB per 5-minute period. Prior to ramp-up, 
SIO will conduct a 30-minute period of observation by at least one 
trained marine mammal observer at the commencement of seismic 
operations and at any time electrical power to the airgun array is 
discontinued for a period of 1 hour or more. SIO will not commence with 
ramping-up of the airguns unless the complete safety radii are visible 
for at least 30 minutes prior in either daylight or nighttime. SIO will 
not initiate seismic profiling during darkness.

Course Alteration

    If a marine mammal is detected at any range beyond the 225 m (738 
ft) safety radius but, based on its position and the relative motion, 
appears to be on a converging course with the ship while profiling is 
underway, the vessel will be maneuvered in an attempt to maintain a 
range greater than the shut-down radius. The marine mammal activities 
and movements relative to the seismic vessel will be closely monitored 
to ensure that the marine mammal does not approach within the safety 
radius. If the mammal appears likely to enter the safety radius, 
further mitigative actions will be taken, i.e., either further course 
alterations or shutdown of the airguns.
    Because of the relative ineffectiveness of mammal observers during 
darkness (even though the vessel is equipped with night-vision 
binoculars), seismic reflection profiling will be concentrated during 
daylight hours.

Monitoring and Reporting

    Effective implementation of these procedures requires surveillance 
by appropriately equipped skilled observers, who will monitor for 
marine mammals in the vicinity of the array. Each leg of the cruise 
will be staffed with two observers who have previously worked for the 
Southwest Fisheries

[[Page 60920]]

Science Center of NMFS, and who are recommended by the Center. These 
observers will share surveillance duties during daylight hours, and be 
responsible for computer entry of their observations while off watch. 
They will be equipped with binoculars and have access to the 50X ``big-
eye'' binoculars mounted on the Revelle's bridge. For estimating the 
range of marine mammals that are sighted, the observers will use the 
optical fixed-interval range-finder described by Heinemann (1981); this 
instrument relies on measuring the angle between the mammal and the 
visual horizon, by an observer at known height above sea-level. The 
observers will be in wireless communication with ship officers on the 
bridge and scientists in the vessel's operations laboratory, so they 
can advise promptly of the need for avoidance maneuvers or G.I. gun 
shut-down.
    Monitoring of marine mammals by experienced observers will occur 
during all daylight hours of the 3 legs of the cruise on the Revelle, 
whether or not G.I. guns are in operation. Except in bad weather, when 
they will occupy the bridge, observers will be stationed outside, 
forward on the 03 upper deck at a height of 9 m (30 ft) above the 
waterline; this has proved to be an effective station for marine mammal 
surveillance during previous mammal and seabird monitoring exercises 
from the Revelle.

Reporting

    Observers will record their observations and range measurements on 
tape, for subsequent transcription into NMFS format. When a marine 
mammal or sea turtle sighting is made, the following information about 
the sighting will be recorded: (1) Species, group size, 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 seismic vessel 
(e.g., none, avoidance, approach, paralleling, etc.), and behavioral 
pace; and (2) time, location, heading, speed, activity of the vessel 
(seismic activity or not), sea state, visibility, cloud cover, and sun 
glare. The data listed under (2) above will also be recorded at the 
start and end of each observation watch and during a watch, and 
whenever there is a change in one or more of the variables.
    Results from the vessel-based observations of marine mammals and 
sea turtles will provide: (1) the basis for real-time mitigation 
(airgun shutdown); (2) information needed to estimate the number of 
animals potentially taken by harassment, which must be reported to 
NMFS; (3) data on the occurrence, distribution, and activities of 
marine mammals and sea turtles in the area where the seismic study is 
conducted; (4) information to compare the distance and distribution of 
animals relative to the source vessel at times with and without seismic 
activity; and (5) data on the behavior and movement patterns of marine 
mammals and sea turtles seen at times with and without seismic 
activity.
    SIO will submit a report to NMFS within 90 days after the end of 
the seismic profiling program (June 2004). The report will be submitted 
to NMFS, providing full documentation of methods, results, and 
interpretation pertaining to most all monitoring tasks. The 90-day 
report will summarize the dates and locations of seismic operations, 
sound measurement data, marine mammal and sea turtle sightings (dates, 
times, locations, activities, associated seismic survey activities), 
and estimates of the amount and nature of potential ``take'' of marine 
mammals by harassment or in other ways. The draft report will be 
considered the final report unless comments and suggestions are 
provided by NMFS within 60 days of its receipt of the draft report.

Estimates of Take by Harassment for the ETP Cruise

    As described previously (see 68 FR 17909, April 14, 2003), animals 
subjected to sound levels 160 dB may experience disruption 
in their behavioral patterns and therefore might be taken by Level B 
harassment.
    The estimates of takes by harassment are based on the number of 
marine mammals that might be found within the 160-dB isopleth radius 
and potentially disturbed by operations with the 2 GI-guns planned for 
the project. Based on summer/fall marine mammal density calculations by 
Ferguson and Barlow (2001), SIO used their average marine mammal 
densities from the ETP to compute a ``best estimate'' of the number of 
marine mammals that may be exposed to seismic sounds [gteqt]160 dB re 
1microPa (rms) (NMFS' current criterion for onset of Level B 
harassment). The average densities were then converted to per-km 
abundances and multiplied (for the appropriate region) by the area that 
is planned to be ensonified at levels [gteqt]160 dB re 1microPa (rms) 
during the proposed seismic survey program. Where abundance estimates 
for certain species (pacific white-sided dolphins, pygmy sperm whales, 
minke whales, and humpback whales) were not readily available for 
stocks found within the proposed survey areas, minimum population 
estimates were taken from individual Marine Mammal Stock Assessment 
Reports, which are available online as mentioned previously.
    SIO did not estimate numbers of pinnipeds potentially vulnerable to 
harassment due to insufficient data on distribution, seasonal 
abundance, and pinniped response. However, NMFS agrees with SIO's 
determination that it is unlikely to encounter significant numbers of 
any of the pinniped species that live, at least part of the year, in 
the area of the proposed activity.
    Based on this method, Table 3 in the application gives the best 
estimates of numbers for each species of cetacean that might be exposed 
to received levels [gteqt]160 dB re 1 microPa (rms), and thus 
potentially taken by Level B harassment, during seismic surveys in the 
proposed study areas of the ETP.
    Eight species of delphinidae would account for 95 percent of the 
overall estimate for potential taking by harassment. Common dolphins 
are the most abundant delphinid in the proposed seismic survey areas, 
representing 71 percent of the total estimate for potential taking by 
harassment. Most of the remaining 5 percent of the overall estimate for 
potential taking by harassment consists of pilot whales, dwarf sperm 
whales, and five species of beaked whales.

Conclusions-effects on Cetaceans

    Baleen whales have been seen to avoid operating airguns with 
avoidance radii that are quite variable, while some baleen whales show 
considerable tolerance of seismic pulses. Whales are often reported to 
show no overt reactions to airgun pulses at distances beyond a few 
kilometers, even though the pulses remain well above ambient noise 
levels out to much longer distances. However, recent studies of 
humpback and especially bowhead whales in the arctic show that 
reactions, including avoidance, sometimes extend to greater distances 
than documented earlier, possibly even exceeding the distances at which 
boat-based observers can see whales. However, reactions at such long 
distances appear to be atypical of other species of mysticetes, and 
even for bowheads may only apply during migration. Moreover, few 
mysticetes occur in the area where seismic surveys are proposed.
    Odontocete reactions to seismic pulses, or at least those of 
dolphins, are expected to extend to lesser distances than those of 
mysticetes. Odontocete low-frequency hearing is less sensitive than 
that of mysticetes, and dolphins are often seen from seismic vessels, 
occasionally even at close distances. In fact, there are documented 
instances of dolphins approaching active seismic

[[Page 60921]]

vessels. However, dolphins as well as some other types of odontocetes 
sometimes show avoidance responses and/or other changes in behavior 
when near operating seismic vessels.
    For most species, including endangered sperm and blue whales, the 
total estimated ``take by harassment'' by species presented in Table 3 
of the application (Scripps 2003) represents less than 1.0 percent of 
the eastern tropical Pacific population of any of these species. For 
the remaining three cetacean species, the total estimated ``take by 
harassment'' is 1.8 percent of the estimated pygmy sperm whale 
population in and adjacent to the study area, 6.2 percent of the dwarf 
sperm whale population, and 1.8 percent of endangered humpback whales. 
Although the absolute numbers of odontocetes that may be harassed by 
the proposed activities may be large, the population sizes of the main 
species are also large; therefore, the numbers potentially affected are 
small relative to the population sizes.
    Taking account of the mitigation measures that are planned, effects 
on cetaceans are generally expected to be limited to avoidance of the 
area around the seismic operation and short-term changes in behavior, 
falling within the MMPA definition of ``Level B harassment.'' Based on 
the relatively low numbers of marine mammals that will be exposed at 
levels 160 dB and the expected impacts at these levels, NMFS 
has determined that this action will have a negligible impact on the 
affected species or stocks of cetaceans.

Conclusions-effects on Pinnipeds

    Responses of pinnipeds to acoustic disturbance are variable, but 
usually quite limited. Early observations provided considerable 
evidence that pinnipeds are often quite tolerant of strong pulsed 
sounds. Visual monitoring from seismic vessels has shown only slight 
(if any) avoidance of airguns by pinnipeds, and only slight (if any) 
changes in behavior. These studies show that pinnipeds frequently do 
not avoid the area within a few hundred meters of an operating airgun 
array. Even so, results from initial telemetry studies suggest that 
avoidance and other behavioral reactions may be stronger than has been 
evident from visual studies.
    Very few, if any, pinnipeds are expected to be encountered during 
the proposed seismic survey by Scripps in the ETP.
    If pinnipeds are encountered, the proposed seismic activities would 
have, at most, a short-term effect on their behavior and no long-term 
impacts on individual seals or their populations. Effects are expected 
to be limited to short-term and localized behavioral changes falling 
within the MMPA definition of Level B harassment. These effects would 
have no more than a negligible impact on the affected species or stocks 
of pinnipeds.

Determinations

    Based on the information contained in the SIO application, the EA 
referenced herein, and the August 26, 2003 (68 FR 51245) Federal 
Register notice and this document, NMFS has determined that conducting 
a seismic survey program in the ETP by the Revelle would result in the 
harassment of small numbers of marine mammals; would have no more than 
a negligible impact on the affected marine mammal stocks; and would not 
have an unmitigable adverse impact on the availability of stocks for 
subsistence uses. This activity will result, at worst, in a temporary 
modification in behavior by certain species of marine mammals. While 
behavioral modifications may be made by these species as a result of 
seismic survey activities, this behavioral change is expected to result 
in no more than a negligible impact on the affected species. While the 
number of potential incidental harassment takes 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. In addition, no take by injury and/or death is 
anticipated, and the potential for temporary or permanent hearing 
impairment is low and will be avoided through the incorporation of the 
mitigation measures mentioned in this document and required under the 
IHA. For these reasons therefore, NMFS has determined that the 
requirements of section 101(a)(5)(D) of the MMPA have been met and the 
authorization can be issued.

Endangered Species Act (ESA)

    NMFS has concluded consultation under section 7 of the ESA on NMFS' 
issuance of an IHA to take small numbers of marine mammals, by 
harassment, incidental to conducting an oceanographic seismic survey in 
the ETP by SIO. The consultation concluded with a biological opinion 
that this action is not likely to jeopardize the continued existence of 
marine species listed as threatened or endangered under the ESA. No 
critical habitat has been designated for these species in the ETP; 
therefore, none will be affected. The Biological Opinion concluded that 
1 fin whale may be harassed during the seismic surveys, and that 
Guadalupefur seals are not likely to be adversely affected by the 
proposed research activities. Therefore, NMFS has removed the Guadalupe 
fur seal from, and added the fin whale to, the proposed list of species 
authorized to be taken by Level B harassment under the IHA. A copy of 
the Biological Opinion is available upon request (see ADDRESSES).

National Environmental Policy Act (NEPA)

    An Environmental Assessment (EA) on a similar action for this area 
of the Pacific Ocean was prepared and released to the public on July 
11, 2003 (68 FR 41314). NMFS' analysis resulted in a Finding of No 
Significant Impact (FONSI). The SIO acoustic survey described in this 
document will use acoustic instruments that are significantly less 
intense and will therefore have a significantly lower impact on the 
marine environment than acoustic sources addressed in the EA. 
Therefore, based on that EA, and review of the information contained in 
the IHA application from Scripps, NMFS has made a finding that this 
action will not have a significant effect, individually or 
cumulatively, on the human environment. Further, this is an action of 
limited size or magnitude. Accordingly, under NAO 216-6, the action is 
categorically excluded from the need to prepare another environmental 
assessment or environmental impact statement. A copy of the relevant EA 
and FONSI is available (see ADDRESSES).

Authorization

    NMFS has issued an IHA to take small numbers of marine mammals, by 
harassment, incidental to conducting a seismic survey by the Revelle in 
the ETP to Scripps for a 1-year period, provided the proposed 
mitigation, monitoring, and reporting requirements described in this 
document and the IHA are incorporated.

    Dated: October 17, 2003.
Donna Wieting,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 03-26929 Filed 10-23-03; 8:45 am]
BILLING CODE 3510-22-S