[Federal Register Volume 64, Number 43 (Friday, March 5, 1999)]
[Notices]
[Pages 10644-10648]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-5497]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration
[I.D. 021699A]


Small Takes of Marine Mammals Incidental to Specified Activities; 
Seismic Hazards Investigation in Southern California

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

ACTION: Notice of receipt of application and proposed authorization for 
a small take exemption; request for comments.

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SUMMARY: NMFS has received a request from the U.S. Geological Survey 
(USGS) for an authorization to take small numbers of marine mammals by 
harassment incidental to collecting marine seismic-reflection data 
offshore from southern California. Under the Marine Mammal Protection 
Act (MMPA), NMFS is requesting comments on its proposal to authorize 
the USGS to incidentally take, by harassment, small numbers of marine 
mammals in the afore mentioned area for a 2-week period between May and 
July 1999.

DATES: Comments and information must be received no later than April 5, 
1999.

ADDRESSES: Comments on the application should be addressed to Donna 
Wieting, Acting Chief, Marine Mammal Division, Office of Protected 
Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910-3225. 
A copy of the application may be obtained by writing to this address or 
by telephoning one of the contacts listed here.

FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead, NMFS, (301) 
713-2055, or Christina Fahy, NMFS, 562-960-4017.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
directs 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

[[Page 10645]]

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. The MMPA now defines ``harassment'' as:

     ...any act of pursuit, torment, or annoyance which (a) has the 
potential to injure a marine mammal or marine mammal stock in the 
wild; or (b) 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.

    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 January 15, 1999, NMFS received a request from the USGS for 
authorization to take small numbers of several species of marine 
mammals by harassment incidental to collecting marine seismic-
reflection data offshore from southern California. Seismic data will be 
collected during a 2-week period between May and July 1999, to support 
studies of the regional landslide and earthquake hazards and to 
understand how saltwater invades
    coastal aquifers. A revised request was received on February 11, 
1999.

Background

    The USGS proposes to conduct a high-resolution seismic survey 
offshore from Southern California, for a 2-week period between May and 
July 1999. The USGS would like to collect seismic-reflection data to 
investigate: (1) the hazards posed by landslides and potential 
earthquake faults in the nearshore region from Santa Barbara to San 
Diego and (2) the invasion of seawater into freshwater aquifers that 
are critical to the water supply for people within the Los Angeles-San 
Pedro area. Both of these tasks are multi-year efforts that require 
using a small airgun.
    Coastal Southern California is the most highly populated urban area 
along the U.S. Pacific coast. The primary objective of the USGS 
research is to provide information to help mitigate the earthquake 
threat to this area. The USGS emphasizes that the goal is not 
earthquake prediction but rather an assistance in determining what 
steps might be taken to minimize the devastation should a large quake 
occur. The regional earthquake threat is known to be high, and a major 
earthquake could adversely affect the well being of a large number of 
people.
    Important geologic information that the USGS will derive from this 
project's seismic-reflection data concerns how earthquake deformation 
is distributed offshore, that is, where the active faults are and what 
the history of movement along them has been. This should improve 
understanding of the shifting pattern of deformation that occurred over 
both the long term (approximately the last 100,000 years) and short 
term (the last few thousand years). The USGS seeks to identify actively 
deforming structures that may constitute significant earthquake 
threats. The USGS also proposes to locate offshore landslides that 
might affect coastal areas. Not only major subsea landslides might 
affect the footings of coastal buildings, but also very large slides 
can generate local tsunamis. These large sea waves can be generated by 
seafloor movement that is produced either by landslides or by 
earthquakes. Knowing where large slides have occurred offshore will 
help locate areas susceptible to wave inundation.
    Some faults that have produced earthquakes lie entirely offshore or 
extend into offshore areas where they can be studied using high-
resolution seismic-reflection techniques. An example is the Rose Canyon 
fault, which extends through the San Diego area, and is considered to 
be the primary earthquake threat. This fault extends northward from La 
Jolla, beneath the inner continental shelf, and appears again onshore 
in the Los Angeles area. This fault and others like it near shore could 
generate moderate (M5-6) to large (M6-7) earthquakes.
    Knowing the location and geometry of fault systems is critical to 
estimating the location and severity of ground shaking. Therefore the 
results of this project will contribute to decisions involving land 
use, hazard zonation, insurance premiums, and building codes.
    The proposed work is in collaboration with scientists at the 
Southern California Earthquake Center, which analyzes faults and 
earthquakes in onshore regions, and with scientists at the Scripps 
Institute of Oceanography, who measure strain (incremental movement) on 
offshore faults.
    The USGS also wants to collect high-resolution seismic- reflection 
data to locate the sources and pathways of seawater that intrudes into 
freshwater aquifers below San Pedro. Ground water usage in the Los 
Angeles basin began in the mid-1800s. Today, more than 44,000 acre-feet 
of freshwater each year are extracted from the aquifers that underlie 
just the city of San Pedro. Extracting freshwater from coastal aquifers 
causes offshore salt water to flow toward areas of active pumping. To 
limit this salt-water intrusion, the Water Replenishment District and 
water purveyors in San Pedro are investing $2.7 million per year to 
inject freshwater underground to establish a zone of high water 
pressure in the aquifer. The resulting zone of high pressure will form 
a barrier between the invasive saltwater and the productive coastal 
aquifers.
    USGS scientists in San Diego are working with the Los Angeles 
County Department of Public Works and the Water Replenishment District 
to develop a ground-water simulation model to predict fluid flow below 
San Pedro and nearby parts of the Los Angeles Basin. This model will 
eventually be used in managing water resources. The accuracy of the 
present model, however, is compromised by a paucity of information 
about aquifer geometry and about other geologic factors that might 
affect fluid flow. Data the USGS collects will be used to improve 
three-dimensional, fluid-flow models to aid management of water 
resources.
    Fieldwork described here will be the third airgun survey that the 
USGS has conducted under close supervision by marine-mammal biologists. 
In March 1998, the USGS used a large (6500 in3; 106 liters) 
airgun array in and around Puget Sound to study the regional earthquake 
hazard. The USGS employed 12 biologists, who worked on two ships 
continuously to oversee airgun operations. On several occasions the 
USGS shut off the airguns when marine mammals entered safety zones that 
had been stipulated by NMFS under an Incidental Harassment 
Authorization (IHA), and, when mammals left these zones, the USGS 
gradually ramped up the array as required to avoid harming

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wildlife. Marine-mammal biologists reported that, during the survey, no 
overt distress was evident among the dense marine mammal populations, 
and, afterward, no unexplained marine mammal strandings occurred.
    In August 1998, the USGS surveyed offshore from Southern 
California, using a small airgun (40 in3; 655 
cm3). Two marine mammal biologists oversaw this activity, 
and the survey the USGS proposes will be conducted with similar 
oversight.

Experimental Design

    Marine studies conducted by the USGS focus on areas where natural 
hazards have their greatest potential impact on society. In Southern 
California, USGS studies will concern four areas. The first area in 
priority is the coastal zone and continental shelf between Los Angeles 
and San Diego, where much of the hazard appears to be associated with 
strike-slip faults, such as the Newport-Inglewood and Palos Verdes 
faults. The second study area lies offshore, in the Santa Monica, San 
Pedro, and San Diego Trough deeps, where rapid sedimentation has left a 
more complete record, relative to shallow-water areas, that the USGS 
can use to decipher earthquake history. The third area is the extension 
into the Santa Barbara Channel of major elements of onshore geology, 
including some large faults. The fourth area is the geologic boundary, 
marked generally by the Channel Islands, between the inner California 
Borderland (dominated by strike-slip faults) and the Santa Barbara 
Channel (dominated by compressional faults). The study proposed here 
focuses on the highest priority area, which lie near shore between Los 
Angeles and San Diego.
    The seismic-reflection survey will last 14 days. From its 
experience collecting seismic-reflection data in this general area 
during 1998, the USGS has decided to conduct the 1999 survey sometime 
within the May through July window. The basis for this decision is its 
desire to avoid the gray whale migrations and the peak arrival of other 
mysticete whales during late summer.
    The USGS has not yet determined the exact tracklines for the 
survey, but the USGS does know the areas where airgun use will be 
concentrated. Two of these areas are southwest and southeast of Los 
Angeles, and the third and largest one is west and northwest of San 
Diego. In these areas seismic-reflection data will be collected along a 
grid of lines that are about 2 km (1.2 mi) apart.
    The USGS proposes to use a small airgun and 200-m (656-ft) long 
streamer to collect seismic-reflection data. The potential effect on 
marine mammals is from the airgun; mammals cannot become entangled in 
the streamer. The USGS will also use a low-powered, high-resolution 
seismic system to obtain detailed information about the very shallow 
geology. The seismic- reflection system will be aboard a vessel owned 
by a private contractor. Ocean-bottom seismometers will be deployed to 
measure the velocity of sound in shallow rocks to help unravel the 
recent history of fault motion. These seismometers are passive 
recorders and pose no threat to the environment.
    Ship navigation will be accomplished using satellites of the Global 
Positioning System. The survey ship will be able to report accurate 
positions, which is important to mitigating the airgun's effect on 
marine mammals and to analyzing what impact, if any, airgun operations 
had on the environment.

The Seismic Sound Sources

    During this survey the USGS will operate two sound sources--an 
airgun and a high-resolution Huntec(TM) system. The main 
sound source will be a single small airgun of special type called a 
generator-injector, or GI-gun (trademark of Seismic Systems, Inc., 
Houston, TX). This type of airgun consists of two small airguns within 
a single steel body. The two small airguns are fired sequentially, with 
the precise timing required to stifle the bubble oscillations that 
typify sound pulses from a single airgun of common type. These 
oscillations impede detailed analysis of fault and aquifer structure. 
For arrays consisting of many airguns, bubble oscillations are 
cancelled by careful selection of airgun sizes. The GI-gun is a mini-
array that is carefully adjusted to achieve the desired bubble 
cancellation. Airguns and GI-guns with similar chamber sizes have 
similar peak output pressures.
    The GI-gun for this survey has two equal-sized chambers of 35 
in3 (57 mm3), and the gun will be fired every 12 
seconds. Compressed air delivered to the GI-gun will have a pressure of 
about 3000 psi. The gun will be towed 12 meters (39.4 ft) behind the 
vessel and suspended from a float to maintain a depth of about 1 m (3.3 
ft).
    The manufacturer's literature indicates that a GI-gun of the size 
the USGS will use has a sound-pressure level (SPL) of about 220 dB re 1 
Pa-m. In comparison, a 40-in3 (65 mm3) 
airgun has an SPL of 216 dB re 1 Pa-m (Richardson et al., 
1995). The GI-gun's output sound pulse has a duration of about 10 ms. 
The amplitude spectrum of this pulse, as shown by the manufacturer's 
data, indicates that most of the sound energy is at frequencies below 
500 Hz. Field measurements by USGS personnel indicate that the GI-gun's 
output is low amplitudes at frequencies above 500 Hz. Thus high-
amplitude sound from this source is at frequencies that are outside the 
main hearing band of odontocetes and pinnipeds (Richardson et al., 
1995).
    The high-resolution Huntec(TM) system uses an 
electrically powered sound source. In operation, the sound producing 
and recording hardware are towed behind the ship near the seabottom. 
The unit emits sound about every 0.5 sec. This system provides highly 
detailed information about stratified sediment, so that dates obtained 
from fossils in sediment samples can be correlated with episodes of 
fault offset. The SPL for this unit is 210 dB re 1 Pa-m. The 
output-sound bandwidth is 0.5 kHz to 8 kHz, with the main peak at 4.5 
kHz.

The Need for 24-hour Seismic Operations

    Operating less than 24 hours each day incurs substantially 
increased cost for the leased ship, which the USGS cannot afford. The 
ship schedule provides a narrow time window for this project; other 
experiments are already scheduled to precede and follow this one. Thus, 
the USGS is not able arbitrarily to extend the survey time to include 
large delays for dark or poor visibility. Reasons for around-the-clock 
operation that benefit the environment are (1) when the airgun ceases 
to operate, marine mammals might move back into the survey area and 
incur an increased potential for harm when operations resume and (2) 
daylight-only operations prolong activities in a given area, thus 
increasing the likelihood that marine mammals will be harassed. The 
1999 survey will require only 2 weeks, and it will be spread out 
geographically from Los Angeles to San Diego, so no single area will 
see long-term activity. In the view of the USGS, the best course is to 
complete the experiment as expeditiously as possible. For these 
reasons, the USGS requests that the IHA allow 24-hour operations.

Description of Habitat and Marine Mammals Affected by the Activity

    The Southern California Bight supports a diverse assemblage of 29 
species of cetaceans (whales, dolphins and porpoises) and 6 species of 
pinnipeds (seals and sea lions). The species of marine mammals that are 
likely to be present in the seismic research area include the 
bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus 
delphis), killer

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whale (Orcinus orca), Pacific white-sided dolphin (Lagenorhynchus 
obliquidens), northern right whale dolphin (Lissodelphis borealis), 
Risso's dolphin (Grampus griseus), pilot whales (Globicephala 
macrorhynchus), Dall's porpoise (Phocoenoides dalli), sperm whale, 
humpback whale (Megaptera novaengliae), gray whale (Eschrichtius 
robustus), blue whale, minke whale (Balaenoptera acutorostrata), fin 
whales (Balaenoptera physalus), harbor seal (Phoca vitulina), elephant 
seal (Mirounga angustirostris), northern sea lion (Eumetopias jubatus), 
and California sea lion (Zalophus californianus), northern fur seal 
(Callorhinus ursinus) and sea otters (Enhydra lutris). General 
information on these latter species can be found in the USGS 
application and in Barlow et al. (1997). Please refer to those 
documents for information on the biology, distribution, and abundance 
of these species.

Potential Effects of Seismic Surveys on Marine Mammals

Discussion

    Seismic surveys are used to obtain data about rock formations up to 
several thousands of feet deep. These surveys are accomplished by 
transmitting sound waves into the earth, which are reflected off 
subsurface formations and recorded with detectors in the water column. 
A typical marine seismic source is an airgun array, which releases 
compressed air into the water creating an acoustical energy pulse that 
is directed downward toward the seabed. Hydrophones spaced along a 
streamer cable just below the surface of the water receive the 
reflected energy from the subsurface formations and transmit data to 
the seismic vessel. Onboard the vessel, the signals are amplified, 
digitized, and recorded on magnetic tape.
    Disturbance by seismic noise is the principal means of taking by 
this activity. Vessel noise may provide a secondary source. Also, the 
physical presence of vessel(s) could also lead to some non-acoustic 
effects involving visual or other cues.
    Depending upon ambient conditions and the sensitivity of the 
receptor, underwater sounds produced by open-water seismic operations 
may be detectable some distance away from the activity. Any sound that 
is detectable is (at least in theory) capable of eliciting a 
disturbance reaction by a marine mammal or of masking a signal of 
comparable frequency. An incidental harassment take is presumed to 
occur when marine mammals in the vicinity of the seismic source (or 
vessel) react to the generated sounds or to visual cues.
    Seismic pulses are known to cause some species of whales, including 
gray whales, to behaviorally respond within a distance of several 
kilometers (Richardson et al., 1995). Although some limited masking of 
low-frequency sounds is a possibility for those species of whales using 
low frequencies for communication, the intermittent nature of seismic 
source pulses will limit the extent of masking. Bowhead whales, for 
example, are known to continue calling in the presence of seismic 
survey sounds, and their calls can be heard between seismic pulses 
(Richardson et al., 1986).
    When the received levels of noise exceed some behavioral reaction 
threshold, cetaceans will show disturbance reactions. The levels, 
frequencies, and types of noise that will elicit a response vary 
between and within species, individuals, locations and seasons. 
Behavioral changes may be subtle alterations in surface-dive-
respiration cycles. More conspicuous responses include changes in 
activity or aerial displays, movement away from the sound source, or 
complete avoidance of the area. The reaction threshold and degree of 
response are related to the activity of the animal at the time of the 
disturbance. Whales engaged in active behaviors, such as feeding, 
socializing, or mating are less likely than resting animals to show 
overt behavioral reactions, unless the disturbance is directly 
threatening.
    Hearing damage is not expected to occur during the project. While 
it is not known whether a marine mammal very close to the airgun would 
be at risk of permanent hearing impairment, temporary threshold shift 
is a theoretical possibility for animals very close to the airgun. 
However, planned monitoring and mitigation measures (described later in 
this document) are designed to detect marine mammals occurring near the 
seismic source(s) and to avoid, to the greatest extent practicable, 
exposing them to sound pulses that have any possibility of causing 
hearing damage.

Maximum Sound-Exposure Levels for Marine Mammals

    At this time, the USGS lacks detailed measurement of sound-
transmission loss for the southern California offshore, so the USGS 
estimated how SPL varies with distance from the airgun by assuming that 
sound decays according to 25log(R). The coefficient 25 accounts 
approximately for the attenuation that is caused by the sound 
interacting with the seabottom. The USGS used this procedure to derive 
safety zone estimates based on the 220 dB SPL produced by the GI-gun, 
the larger of the two sound sources the USGS plans to use.
    Loud continuous sounds can damage the hearing of marine mammals. 
However, the adverse effects of sound on mammals have been documented 
for exposure times that last for tens of seconds or minutes, but 
effects have not been documented for the brief pulses typical of the 
GI-gun (10 ms) and the Huntec(TM) system (0.3 ms). NMFS 
considers that the maximum SPLs to which marine mammals can be exposed 
from impulse sounds are 180 dB re 1 Pa-m RMS for mysticetes 
and sperm whales, and 190 dB re 1 Pa-m RMS for odontocetes and 
pinnipeds.
    Assuming that the 25LogR decay that the USGS used to estimate safe 
distances from the airgun is correct, this indicates that an SPL of 190 
dB re 1 Pa-m is attained about 16 m (52.5 ft) away from the 
airgun, and an SPL of 180 dB re 1 Pa-m is attained at about 40 
m (131 ft) away. However, for precautionary reasons during field 
operations, the USGS proposes that, at all times, the safe distance for 
odontocetes and pinnipeds be 50 m (164 ft) and for mysticetes, 100 m 
(328 ft).

Estimated Number of Potential Harassments of Marine Mammals

    The zone of influence for the GI-gun is defined to be the circle 
whose radius is the distance from the gun where the SPL reduces to 160 
dB re 1 Pa-m. For the assumed 25LogR, the zone of influence is 
a circle with a radius of 250 m (820 ft). Based on estimated marine 
mammal populations within the survey area and on the number of 
individuals that were observed during the 1998 survey, the USGS 
estimates that up to 5 killer whales, 10 minke whales, 10 sea otters, 
50 northern sea lions, 100 northern fur seals, 100 northern elephant 
seals, 100 Dall's porpoise, 100 Risso's dolphins, 100 northern right-
whale dolphins, 100 Pacific white-sided dolphins, 100 bottlenosed 
dolphins, 200 California sea lions, 200 Pacific harbor seals, and 6,000 
common dolphins may be harassed incidental to the USGS survey. No 
marine mammals will be seriously injured or killed as a result of the 
survey.

Proposed Mitigation of Potential Environmental Impact

    To avoid potential harassment of marine mammals, a safety zone will 
be established and monitored continuously by biologists, and the USGS 
will shut off the airguns whenever the ship and a marine mammal 
converge closer than

[[Page 10648]]

the previously mentioned safety distance. For pinnipeds, if the seismic 
vessel approaches a pinniped, the 50 m (164 ft) safety radius will be 
maintained; however, if a pinniped approaches the towed airgun, NMFS 
proposes that it will not require the USGS to shutdown the airgun, but 
will require the USGS to monitor the interaction to ensure the animal 
does not show signs of distress. Experience indicates that pinnipeds 
will come from great distances to inspect seismic operations. Seals 
have been observed swimming within airgun bubbles, 10 m (33 ft) away 
from active arrays, apparently unaffected. Although airgun oprations 
will be terminated if the pinnipeds show obvious distress, the USGS 
will conduct observations on effects the airguns may have on the 
animals.
    The USGS plans to have marine biologists aboard the ship who will 
have the authority to stop airgun operations when a mammal enters the 
safety zone.
    During seismic-reflection surveying, the ship's speed will only be 
4 to 5 knots, so that when the airgun is being discharged, nearby 
marine mammals will have gradual warning of the vessel's approach and 
can move away. Finally, NMFS will coordinate with the local stranding 
network to determine whether strandings can be related to the seismic 
operation.

Monitoring and Reporting

    Biologists who oversaw the previous USGS airgun surveys were 
affiliated with the Cascadia Research Collective in Olympia, 
Washington. Because of their experience with the operations, the USGS 
prefer to employ these scientists again, but this preference is subject 
to contracting arrangements.
    Monitoring marine mammals while the airguns are active will be 
conducted 24 hours each day. Two trained marine mammal observers will 
be aboard the seismic vessel to mitigate the potential environmental 
impact from airgun use and to gather data on the species, number, and 
reaction of marine mammals to the airgun. Each observer will work 6 
hours during daylight and 6 hours at night. During daylight, observers 
will use 7x50 binoculars with internal compasses and reticules to 
record the horizontal and vertical angle to sighted mammals. Night-time 
operations will be conducted with a commercial hand-held light 
magnification scope. Monitoring data to be recorded during airgun 
operations include the observer on duty, weather conditions (such as 
Beaufort sea state, wind speed, cloud cover, swell height, 
precipitation, and visibility). For each mammal sighting, the observer 
will record the time, bearing and reticule readings, species, group 
size, and the animal's surface behavior and orientation. Observers will 
instruct geologists to shut off the airgun array whenever a marine 
mammal enters its respective safety zone.

Possible Modifications or Alternatives to the Proposed Survey

    The instructions for this permit request stipulate that the USGS 
consider alternatives to the proposed experiment. Options to change the 
activity are limited, but the USGS might conduct it in some other way, 
such as with a low-powered source or in a different season.
    To abandon this study altogether is a poor option. In the 
introductory section of this application, the USGS described the 
societal relevance of this project and the benefits to scientists in 
understanding the regional earthquake hazard and to city planners in 
establishing building codes. Another facet of this study is 
understanding coastal aquifers and knowing how to stem the intrusion of 
salt water into them. If the project were canceled, such information 
would be unavailable.
    The source strength might be reduced to limit the environmental 
impact. However, the proposed airgun size is already small, and the 
problem with this option is that the USGS cannot significantly reduce 
the source strength without jeopardizing the success of this survey. 
This judgment is based on USGS decades-long experience with seismic-
reflection surveys, but especially on the 1998 survey that was 
conducted in the same general area as outlined here. If the USGS were 
to reduce the airgun size and then fail to obtain the required 
information, another survey would need to be conducted, and this would 
double the potential impact on marine mammals.
    This project could be carried out at some other time of year, and 
the USGS is open to suggestions. In this pursuit, the USGS talked with 
biologists to find out the best time for the project to be conducted. 
The USGS wants to avoid the gray whale migrations and the mid-summer 
arrival of other mysticete species because, while these other species 
remain mostly in the area of the Channel Islands, some individuals 
venture closer to the mainland. An important point is that biologists 
can best prevent harm to mammals when daylight is long, that is, near 
the solstice.

Consultation

    Under section 7 of the Endangered Species Act, NMFS has begun 
consultation on the proposed issuance of an IHA. Consultation will be 
concluded upon completion of the comment period and consideration of 
those comments in the final determination on issuance of an 
authorization.

Conclusions

    NMFS has preliminarily determined that the short-term impact of 
conducting marine seismic-reflection data in offshore southern 
California will result, at worst, in a temporary modification in 
behavior by certain species of pinnipeds and cetaceans. While 
behavioral modifications may be made by certain species of marine 
mammals to avoid the resultant noise from the seismic airgun, this 
behavioral change is expected to have a negligible impact on the 
animals.
    In addition, no take by injury and/or death is anticipated, and 
takes will be at the lowest level practicable due to the incorporation 
of the mitigation measures previously mentioned. No known rookeries, 
mating grounds, areas of concentrated feeding, or other areas of 
special significance for marine mammals occur within or near the 
planned area of operations during the season of operations.

Proposed Authorization

    NMFS proposes to issue an IHA to the USGS for the possible 
harassment of small numbers of several species of marine mammals 
incidental to collecting marine seismic-reflection data offshore from 
southern California, provided the above-mentioned mitigation, 
monitoring, and reporting requirements are incorporated. NMFS has 
preliminarily determined that the proposed activities would result in 
the harassment of only small numbers of each of several species of 
marine mammals and will have no more than a negligible impact on these 
marine mammal stocks.

Information Solicited

    NMFS requests interested persons to submit comments, information, 
and suggestions concerning this request (see ADDRESSES).

    Dated: March 1, 1999.
P. Michael Payne,
Acting Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 99-5497 Filed 3-4-99; 8:45 am]
BILLING CODE 3510-22-F