[Federal Register Volume 65, Number 247 (Friday, December 22, 2000)]
[Proposed Rules]
[Pages 80815-80827]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-32725]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 216

[Docket No.000801223-0223-01; I.D. 062000A]
RIN 0648-AO24


Taking and Importing Marine Mammals; Taking Marine Mammals 
Incidental to Operation of a Low Frequency Sound Source by the North 
Pacific Acoustic Laboratory

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

ACTION: Notice of proposed rulemaking; request for comments.

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SUMMARY: NMFS has received a request from the University of California 
San Diego, Scripps Institution of Oceanography (Scripps), for a Letter 
of Authorization (LOA) to take a small number of marine mammals 
incidental to the continued operation of a low frequency (LF) sound 
source previously installed off the north shore of Kauai by the 
Acoustic Thermometry of Ocean Climate (ATOC) project. By this notice, 
NMFS is proposing regulations to govern that take. In order to grant 
the exemption and issue the regulations, NMFS must determine that these 
takings will have no more than a negligible impact on the affected 
species and stocks of marine mammals. NMFS invites comment on the 
application and the proposed regulations.

DATES: Comments and information must be postmarked no later than 
February 5, 2001. Comments will not be accepted if submitted via e-mail 
or the Internet.
    Comments regarding the burden-hour estimate or any other aspect of 
the collection of information requirement contained in this rule should 
be sent to the Chief, and to the Office of Information and Regulatory 
Affairs, Office of Management and Budget (OMB), Attention: NOAA Desk 
Officer, Washington, DC 20503.

ADDRESSES: Comments should be addressed to Donna Wieting, Chief, Marine 
Mammal Conservation Division, Office of Protected Resources, National 
Marine Fisheries Service, 1315 East-West Highway, Silver Spring, MD 
20910-3226. A copy of the application, which contains the references 
used in this document, may be obtained by writing to this address or by 
telephoning the contacts listed here (see FOR FURTHER INFORMATION 
CONTACT). A copy

[[Page 80816]]

of the draft environmental impact statement (DEIS) may be obtained from 
Marine Acoustics Inc., 809 Aquidneck Ave., Middletown, RI 02842, attn. 
Kathy Vigness Reposa, 401-847-7508.

FOR FURTHER INFORMATION CONTACT: Kenneth R. Hollingshead (301) 713-
2055, ext. 128, and Margaret Dupree, 808-973-2935, ext. 210.

SUPPLEMENTARY INFORMATION:

Background

    Section 101(a)(5)(A) of the Marine Mammal Protection Act (16 U.S.C. 
1361 et seq.) (MMPA) directs the Secretary of Commerce (Secretary) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified 
geographical region if certain findings are made and regulations 
governing the take are issued.
    Permission may be granted for periods of 5 years or less if the 
Secretary finds that the taking will be small, will have no more than 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 Arctic Ocean subsistence uses, and if regulations are 
prescribed setting forth the permissible methods of taking and the 
requirements pertaining to the monitoring and reporting of such taking.

Summary of Request

    On May 21, 2000, NMFS received an application for an incidental, 
small take authorization under section 101(a)(5)(A) of the MMPA from 
Scripps to take a small number of marine mammals incidental to the 
continued operation of a LF sound source previously installed off the 
north shore of Kauai by the ATOC project. An alternative source 
location under consideration in the DEIS is for Midway Island. A final 
decision on whether to re-use the acoustic source (or to install a new 
source and cable at Midway), in order to combine a second phase of 
research on the feasibility and value of large-scale acoustic 
thermometry with long range underwater sound transmission studies and 
marine mammal monitoring and studies will be made based, in part, on 
findings and determinations made under the National Environmental 
Policy Act (NEPA). As the principal funding agency for the proposed 
action, a DEIS has been prepared by the Office of Naval Research (ONR). 
NMFS is a cooperating agency in the preparation of this DEIS.

Project Description

    Acoustic thermometry is a method for obtaining information about 
the temperature field in the ocean from precise measurements of the 
travel times of sound pulses transmitted through the ocean. It is also 
a technique for acoustic remote sensing of the ocean interior, in which 
the properties of the ocean between the acoustic sources and receivers 
are determined, rather than the properties of the ocean at the 
instruments as is the case for conventional thermometers and current 
meters.
    The purposes for conducting the proposed action are: (1) To perform 
the second phase of research on the feasibility and value of large-
scale acoustic thermometry; and (2) to study the behavior of sound 
transmissions in the ocean over long distances. Large-scale acoustic 
thermometry is needed: (1) To study seasonal and interannual ocean 
variability associated with ocean phenomena such as El Nino, La Nina, 
and the Pacific Decadal Oscillation; (2) to use acoustic thermometry 
data in combination with a variety of other data types, including 
satellite altimeter data, surface drifter data, surface mooring data, 
and others to test and constrain computer models of ocean circulation 
in order to gain a better understanding of ocean variability and the 
earth's changing climate; and (3) to make an objective assessment of 
the value of acoustic methods for remote sensing of the ocean interior 
as one component of an integrated ocean observing system for ocean 
weather and climate.
    Long-range underwater sound transmission studies are needed: (1) To 
improve the understanding of the basic principles of LF, long-range 
underwater sound transmission (i.e., acoustic propagation) in the 
ocean; (2) to determine the effects of ocean environmental variability 
on acoustic signal stability and coherence; (3) to study the seasonal 
and annual variations in acoustic conditions in the North Pacific and 
the impact of environmental variability on acoustic propagation; and 
(4) to determine the fundamental limits to acoustic signal processing 
at long-range imposed by the ocean environment.
    This second phase of acoustic research requires longer time series 
of acoustic measurements in order to determine whether the 
acoustically-derived time series of large-scale ocean temperature and 
heat content variability prove to be as valuable as anticipated in 
studying seasonal and interannual ocean variability. It is anticipated 
that there will be a growing effort to monitor the variability of the 
North Pacific using a combination of satellite altimeter data, surface 
and subsurface drifter data, surface moorings and bathythermograph 
data, in addition to acoustic thermometry data. Combining all of these 
different data types in computer models of the ocean circulation will 
allow testing and refinement of ocean general circulation and climate 
models in order to gain a better understanding of the earth's changing 
climate.
    Under the proposed action, which is for Scripps to operate the 
sound source previously installed off the north shore of Kauai by the 
Acoustic Thermometry of Ocean Climate (ATOC) project, the seabed power 
cable and sound source from the ATOC project would remain in their 
present locations on Kauai, and transmissions would continue with 
approximately the same signal parameters and transmission schedule used 
in the earlier ATOC project. The typical schedule would consist of six 
20-minute (min) transmissions (one every 4 hours), every fourth day, 
with each transmission preceded by a 5-min ramp-up period during which 
the signal intensity is gradually increased, representing an average 
duty cycle of 2 percent. With the possible exception of short duration 
testing with duty cycles of up to 8 percent, or equipment failure, this 
schedule would continue for a period of 5 years. The signals 
transmitted by the source would have a center frequency of 75 Hertz 
(Hz) and a bandwidth of approximately 35 Hz (i.e., sound transmissions 
are in the frequency band of 57.5-92.5 Hz). Approximately 260 watts of 
acoustic power would be radiated during transmission. According to 
Scripps, the signal parameters and source level in the ATOC project 
have been found to provide adequate, but not excessive, signal-to-noise 
ratios in the receiver ranges of interest. At 1 meter (m)(3.3 feet 
(ft)) from the source (at 807 m (2,648 ft) water depth at the Kauai 
location), sound intensity (i.e., source level) would be about 195 
decibels (dB) referenced to the intensity of a signal with a sound 
pressure level (SPL) of 1 microPascal (1 'Pa).
    Average ambient noise levels in the 60-90 Hz band offshore central 
Kauai can be 76-98 dB (with various degrees of shipping traffic) and 
are expected to be higher (105 dB) when humpback whales are present. 
The received level from the NPAL source is not expected to exceed 137 
dB at the water's surface anywhere in the vicinity of the sound source. 
The received level in the top 100 m (328.1 ft) has been measured to 
decrease to about 120 dB at 5 km (2.7 nm) shoreward of the source. The 
near-

[[Page 80817]]

surface received level is predicted to decrease to about 120 dB at 7.5 
km (4 nm) seaward of the source. Underwater sound levels in the 
immediate vicinity of the source are expected to be: 140 dB at 245 m 
(804 ft) depth (562 m (1844 ft) from the source); 145 dB at 491 m (1611 
ft) depth (316 m (1037 ft) from the source; 150 dB at 629 m (2064 ft) 
depth (178 m (564 ft) range around the source); and 165 dB at 775 m 
(2543 ft) (32 m (105 ft) range around source (ONR/NMFS, 2000; ARPA/
NMFS, 1995).
    While Scripps' preferred alternative to use the ATOC source off 
Kauai, HI involves the continued operation of the source installed at 
that location, an alternative under consideration in ONR's DEIS would 
be installing a sound source and cable at a location off the coast of 
Midway Island.

Comments and Responses

    On August 24, 2000 (65 FR 51584), NMFS published a notice of 
receipt of Scripps' application for a small take exemption and 
requested comments, information, and suggestions concerning the request 
and the structure and content of regulations to govern the take. During 
the 30-day public comment period, NMFS received letters from the Office 
of Naval Research (ONR), the Marine Mammal Commission (MMC), the Humane 
Society of the United States (HSUS), Animal Welfare Institute (AWI), 
the Whale and Dolphin Conservation Society (WDCS), the Hawaiian Islands 
Humpback Whale National Marine Sanctuary, the State of Hawaii, and a 
number of U.S. citizens, including several form letters. Comments made 
regarding ONR's DEIS, that are not germane to the Scripps' application 
for taking marine mammals incidental to the activity will be addressed 
in ONR's Final EIS (FEIS). Comments postmarked after the close of the 
comment period are not addressed in this document.

Activity Concerns

    Comment 1: The MMC notes that it is not clear whether the ATOC 
program will terminate in 5 years, as indicated in both the DEIS and 
the request for taking authorization, or continue further.
    Response: NMFS understands that the authorization requested by 
Scripps, for the taking of marine mammals incidental to operating the 
NPAL acoustic source, will be for a single 5-year authorization and 
will not be renewed thereafter. Scripps notes that, by the time the 
next 5-year research and marine mammal monitoring program ends, the 
acoustic source will have been deployed for over 10 years, and 
therefore questions whether it will continue to be usable after that 
time. NMFS notes, however, that if the project was continued 
thereafter, a new small take rulemaking would be required. Moreover, if 
the project were proposed to continue beyond 5 years at the Hawaii 
location (Kauai or Midway), NMFS strongly recommends that long-term 
monitoring studies be designed and carried out so that remaining issues 
regarding cumulative impacts can be addressed.
    Comment 2: Several commenters noted that the application omitted 
discussion and comparison with the beaked whale stranding in the 
Bahamas. One commenter noted that, while the sonar applications are 
different, the application did not mention the beaked whale stranding 
which, the commenter asserted, was caused by a sonar experiment known 
as Littoral Warfare Advanced Deployment (LWAD) Sea Test 00-1. An 
important similarity may be found in the island habitats. Another 
commenter noted that NPAL was the world-wide deployment of the 
Surveillance Towed Array Sensor System Low Frequency Active (SURTASS 
LFA) sonar system with a different name.
    Response: Naval ship sonars have signal and operational 
characteristics very different from those of the Kauai NPAL source. For 
example, in response to the stranding of beaked whales in the Bahamas 
on March 15, 2000, the Navy and NMFS are investigating the transit of 
several ships (not associated with the LWAD 00-1 Sea Test) using 
standard, hull-mounted sonar operations within normal frequency ranges, 
power outputs, and duty cycles, which are, respectively: 3.5 and 7.5 
kHz, 235 dB (and lower) and ``pings'' of short duration (about one-
tenth of a second or less duration on a standard duty cycle of 24 
seconds. Since these sonars do not have signal and operational 
characteristics similar to the NPAL source, ONR does not believe it is 
appropriate for either the DEIS or the small take application to 
analyze those strandings. NMFS concurs.
    The Bahamian beaked whale stranding could not have been caused by 
the LWAD 00-1 Sea Test, because these strandings began prior to the 
Navy's beginning that test. In addition, LWAD Sea Test 00-1 did not 
employ sonar around the time of the strandings. The U.S. Navy and NMFS 
are continuing the investigation into the cause of the beaked whale 
strandings and will report on their findings next summer at the 
conclusion of investigations.
    In addition, NPAL should not be confused with the Navy's SURTASS 
LFA sonar system, a ship-mounted LF sonar array for detecting 
submarines. The two systems have distinctly different operating 
systems, frequencies, duty cycles, and operating characteristics.

Marine Mammal Concerns

    Comment 3: One commenter noted that the Hawaiian monk seal was not 
listed in the application for Kauai waters because preliminary studies 
by Scripps were totally outdated and inadequate. The request did not 
list earlier aerial surveys which reported numerous monk seals around 
Kauai and Niihau. The WDCS believes that Scripps has not given full 
consideration to the impacts of its actions on the marine environment, 
particularly the Hawaiian monk seal, noting that the species lives only 
in the Hawaiian Islands and is very sensitive to human disturbance.
    Response: NMFS has been informed that ONR and Scripps will include 
information in the FEIS on the abundance of Hawaiian monk seals around 
Kauai, that was not available at the time the DEIS was written. In 
addition, ONR and Scripps have added the Hawaiian monk seal to the 
marine mammals species in the Acoustic Integration Model (AIM) for 
Kauai (it was previously modeled only for the Midway alternative). NMFS 
has added this species to the list of marine mammal species potentially 
affected off Kauai. However, NMFS does not believe that Hawaiian monk 
seals will be impacted by the NPAL source considering that monk seals 
are believed to be high-frequency-specialist hearers, the relatively 
low SPL of the NPAL source at the water surface in the offshore 
vicinity of the source (less than 136 dB), and the coastal nature of 
the Hawaiian monk seal where SPLs will be even lower.

Marine Mammal Impact Assessment Concerns

    Comment 4: The HSUS finds that, while the AIM model may result 
academically in the best guesses possible for estimating received 
levels for free ranging animals, it is inadequate for management 
purposes. If cetaceans, or monk seals act contrary to the assumptions 
made in the model, the received levels to which the animals are exposed 
may in fact be far higher (or far lower) than the model predicts, thus 
invalidating the mitigation protocols established by Scripps.
    Response: The MMPA requires NMFS to use the best scientific 
information available when making determinations of negligible impact 
from maritime activities. NMFS believes the AIM

[[Page 80818]]

model incorporates the best scientific information available on each 
species in order to predict the acoustic impact on these species. 
Independent of the AIM model, however, scientific information is 
available to NMFS from several other sources to assist NMFS in making 
its negligible impact determination for this activity. NMFS notes, for 
example, the limited duty cycle of the sound source (2 percent during 
humpback whale presence, 8 percent at other seasons), the depth of the 
sound source (few marine mammals could dive to depths that would put 
them in proximity to sound fields that could affect them), the amount 
of attenuation of the SPL by the time the sounds reach the upper water 
depths, and the LF of the NPAL source that many species of marine 
mammals are unlikely to hear. In addition, the California and Hawaii 
ATOC Marine Mammal Research Programs (MMRPs) did not find any overt or 
obvious short-term changes in the abundance or distribution of marine 
mammals in response to the transmissions of the ATOC sound sources. 
Costa et al. (1998) and Mobley et al. (1999) showed no significant 
changes in the abundance of humpback and sperm whales from the control 
periods, when the source was not operating, to the experimental 
periods, when it was on. While intensive statistical analyses of aerial 
survey data showed some subtle shifts in distribution of humpback (and 
possibly sperm) whales away from the Pioneer Seamount ATOC source 
during transmission periods, no statistically significant shifts in 
distribution were found for any other species of marine mammal. In 
addition, comparison of the 1993, 1995, and 1998 population estimates 
for humpback whales in Hawaii show an almost statistically significant 
increase in population size of approximately 8 percent annually.
    Comment 5: The HSUS believes that the ``single ping equivalent'' 
(SPE) concept is based on assumptions that have not and cannot be 
verified. The calculation that 10 pings at 120 dB are equivalent to one 
ping at 130 dB is entirely speculative--no empirical data were used to 
establish this relationship.
    Response: The SPE concept is explained in detail in ONR's DEIS. The 
purpose of the SPE is to take into account repeated exposure to sound. 
Richardson et al. (1995) discussed the relationship between repeated 
exposures of the human ear to impulsive sound and the temporary 
elevation in hearing sensitivity (referred to as temporary threshold 
shift (TTS)). While recognizing that no empirical data have been 
collected to establish this relationship, and there is no guarantee 
that marine mammal behavioral responses exhibit patterns similar to 
human hearing, the human model is the best objective foundation for an 
assessment and is consistent with Crocker (1997).
    Richardson et al. (1995) noted the risk threshold is lowered by 5 
dB per tenfold increase in the number of sounds in the exposure. As 
such, an SPE RL will always be larger than the maximum RL of any single 
ping in a sequence. In addition, NMFS believes that dividing the 
single, 20-min NPAL source signal into 20 one-minute ``pings'' 
accurately represents the impact on the animals during diving and 
movement. For these two reasons, therefore, NMFS believes that the SPE 
concept, which is based on the best science currently available, is 
significantly more conservative than assumptions made for previous 
marine mammal impact assessments.
    Comment 6: The HSUS express concern that the assumption that a RL 
of 180 dB would result in TTS for 95 percent of exposed baleen whales, 
far from being conservative, is completely unsubstantiated.
    Response: As explained in ONR's DEIS, to date, there are no 
authoritative studies of TTS in mysticetes. However, as noted in the 
DEIS, studies of human hearing indicate that the normal process of 
hearing loss with age (termed presbycusis) can be accelerated by 
chronic exposure to sounds 80 dB above the absolute threshold of 
hearing (Richardson et al., 1995). Here chronic is interpreted as about 
8 hours per day for about 10 years. While hearing thresholds are not 
known in mysticetes, the lowest value is speculated to be 80 dB 
(Ketten, 1998). This suggests that 10 years of exposure to 160 dB RL 
(i.e., 80 dB threshold plus 80 dB exposure level) for 8 hours per day 
would cause auditory damage. As a result, because TTS may result from a 
brief exposure to a loud sound, prolonged exposure to a faint sound, or 
intermediate exposure to a sound of intermediate loudness, sound 
duration and intensity can be considered to trade off with each other 
in causing TTS. Therefore, by estimating that 95 percent of baleen 
whales would experience TTS (a level which would not result in any 
hearing damage), after exposure to a 1-minute ping at 180 dB is 
considered conservative.
    Comment 7: ONR believes that certain language found in the ANPR 
implies that the Navy and Scripps: (1) Categorized harm as the onset of 
TTS; (2) categorized the onset of TTS as the lower end of Level A 
harassment; (3) categorized TTS as the onset for a Level A harassment 
take; and (4) determined that a marine mammal would have to receive one 
ping greater than or equal to 180 dB re 1 micro Pa in order to be 
considered to have received a non-serious injury, or many pings at a 
received level slightly lower than 180 dB re 1 micro Pa in order to 
potentially incur a significant biological response (Level B 
harassment). Each of these statements is inaccurate: Neither Navy nor 
Scripps state in the DEIS or application that TTS is the onset of Level 
A harassment, or that harm is the onset of TTS, or that TTS is a 
threshold for Level A harassment, or that marine mammals are considered 
to receive non-serious injury when exposed to a single ping of LF sound 
from NPAL at a receive level of 180 dB re 1 micro Pa, or that Level B 
harassment occurs when exposed to multiple pings at receive levels 
below 180 dB re 1 micro Pa.
    Response: The model used by the Navy for the SURTASS LFA sonar, 
which is also used by Scripps and ONR for this action, establishes a 
single-ping RL of 180 dB as a scientifically reasonable estimate for 
the potential onset of non-serious injury to marine mammals (Navy, 
1999). According to the Navy (1999), a marine mammal would have to 
receive a single ping greater than, or equal to, 180 dB, or many pings 
at a slightly lower RL to possibly incur non-serious injury. For 
serious injury, the marine mammal would need to be well within the 180-
dB sound field at the onset of the sound transmission. While the ONR 
DEIS and the Scripps' application for a small take authorization do not 
go into the depth of analysis found in other documents (see Navy, 
1999), their use of the same model requires acceptance of the same 
assumptions, unless it is made clear that different assumptions apply. 
At the time of publication of the ANPR for this action, such 
clarification had not been made by the Navy.
    At a workshop on marine mammals and LF sound convened by the 
Minerals Management Service-sponsored High-Energy Seismic Survey (HESS) 
Team in 1997, an expert panel concluded that it was apprehensive about 
levels above 180 dB re 1 'Parms regarding overt behavioral, 
physiological, and hearing effects on marine mammals in general (HESS, 
1997). These concerns were expressed again at an Acoustic Criteria 
workshop convened by NMFS in 1998. The latter workshop clarified, that 
a safety zone for pinnipeds, for impulse sounds only, could be safely 
set at 190 dB, instead of 180 dB, due to their different ear structure 
from cetaceans and, secondarily, to their generally lower sensitivity 
to LF sounds. It must be clarified further however, that the 180/190 dB 
safety zones were

[[Page 80819]]

established for impulse noise, not intermittent noise, such as is under 
discussion in this document and elsewhere. Adopting the precautionary 
approach, safety zones need to be established for the marine mammal 
species most sensitive to the frequency of the sound source that has 
more than a remote potential to be in the area at the time of the 
activity. For LF sounds, the species most likely to be affected are the 
mysticete whales and sperm whales. At this time, there is no evidence 
that TTS would occur in marine mammals at an SPL of 180 dB, and, in 
fact, Schlundt et al. (2000) indicates that onset TTS, for at least 
some species, occurs at significantly higher SPLs.
    NMFS scientists and other scientists are in general agreement that 
TTS is not an injury (i.e., does not result in tissue damage) but is an 
impairment to hearing (resulting in an increased elevation in hearing 
sensitivity) that may last for a few minutes to a few days, depending 
upon the level and duration of exposure. In this document, NMFS makes 
clear that, although TTS is not an injury (i.e., Level A harassment), 
because a permanent elevation in hearing sensitivity (termed permanent 
threshold shift (PTS)) is considered an injury (Level A harassment), 
and because scientists have noted that a range of only 15-20 dB may 
exist between the onset of TTS and the onset of PTS, TTS is considered 
by NMFS to be in the upper portion of the Level B harassment zone (near 
the lower end of the Level A harassment zone). Therefore, onset PTS, 
not onset TTS, is considered by NMFS to be the lower end of Level A 
harassment. NMFS believes that establishing TTS at the upper end of the 
Level B harassment zone is both precautionary and warranted by the 
science. However, mitigation measures, such as establishing safety 
zones, should be applied whenever a marine mammal has the potential to 
incur a TTS in hearing in order to prevent an animal incurring a PTS 
injury.
    Therefore, while the commenter's statement is true, the Navy's 
precautionary approach for assessing impacts by using TTS as the onset 
of non-serious injury needs to be amended to better reflect current 
scientific findings that TTS does not result in injury to a marine 
mammal. For this action, NMFS understands that this clarification will 
be made by ONR in its FEIS on this action.
    Comment 8: ONR further notes that it is not the view of the Navy 
that TTS constitutes injury, harm, or level A harassment under the 
MMPA. TTS is a method of determining when the level of sound input 
temporarily reduces the ear's ability to respond fully (Schlundt et 
al., 2000). TTS is defined as a reversible decrease in hearing 
sensitivity as a result, for example, of exposure to a loud noise 
(Green, 1976). The leading analysis of TTS in marine mammals was 
conducted by Schlundt et al. (2000), in a series of experiments 
involving bottlenose dolphins and white whales. That effort included 
and expanded on pure-tone TTS data collected by Ridgway et al. (1997). 
The analysis generally within the range of 192 to 201 dB re 1 micro Pa, 
for exposures to one-second tones at frequencies of 0.4, 3, 10, 20, and 
75 kHz. The threshold shift was generally in the nature of a 6- to 17-
dB masking in the animal's hearing and was of short duration and 
completely recoverable.
    Response: Please see response to Comment 7.
    Comment 9: The HSUS states that the acceptance of TTS as a working 
definition for Level B harassment, although not expressly stated in the 
LOA request, is implicit in its risk continuum analysis (where 95 
percent of baleen whales are estimated to experience TTS at 180 dB).
    Response: Although NMFS considers TTS to be Level B harassment, a 
sound source would not need to cause TTS in order to result in 
harassment. For impulse, intermittent, and continuous sounds, NMFS 
considers both TTS impairment and any significant behavioral response 
to the signal on the part of the mammal to constitute Level B 
harassment of marine mammals. (Non-significant behavioral responses 
include, but are not limited to, a heads up display by pinnipeds, and 
minor adjustments in course direction or swimming speed by a marine 
mammal). For impulse, intermittent, and continuous types of noise, 
maritime activities such as the one in this document need to consider 
the level of take due to their activities resulting in a significant 
behavioral response. However, for single explosive events, because of 
the extremely short duration of the signal, NMFS scientists and other 
scientists believe that marine mammals cannot have a significant 
behavioral response because of the transient nature of the signal. For 
explosives therefore, only TTS needs to be considered for determining 
the level of Level B impact.
    As mentioned previously, the consensus of scientific opinion is 
that TTS is not an injury. The National Research Council (NRC)(NRC, 
2000), supports this statement noting that animals that experience 
small levels of TTS are not injured, suggesting that TTS is a 
conservative standard for the prevention of injury. However, the risk 
continuum estimates that 95 percent of the marine mammals exposed to a 
single 1-min sound at 180 dB could have the potential for a risk of 
TTS. If 180 dB is accepted as a precautionary de facto level for onset 
TTS (even though onset TTS probably occurs at a significantly higher 
SPL) and TTS itself is not an injury, the Scripps/ONR assumption for 
estimating risk is very conservative.
    Comment 10: The HSUS notes that both the risk analysis and the AIM 
model require assumptions to be made for several key variables; if 
these assumptions are violated or are inaccurate or invalid to begin 
with, then the analysis and model are not valid.
    Response: NMFS believes the AIM model has incorporated the best 
scientific information currently available on the levels of abundance 
of marine mammals in Hawaiian waters and on acoustic characteristics of 
both the ATOC source and surrounding waters. NMFS considers this 
information to be the best information currently available, especially 
since it allows NMFS to consider impacts in three dimensions as opposed 
to the usual two dimensions used in previous impact assessments. 
However, the AIM model is not the only source of information that NMFS 
intends to use in this action for the necessary determinations under 
the MMPA for levels of impacts.
    Comment 11: The HSUS states that the principal assumption of the 
risk analysis is the use of the SPL ``harm'' criteria, which is not 
based on any empirical data. For example, determining these criteria 
requires gross speculation on baleen whale hearing thresholds, which 
are unknown.
    Response: While NMFS agrees that baleen whale hearing thresholds 
are unknown empirically, until such time as this information becomes 
available, the AIM model uses assumptions on pre-industrial era ambient 
noise levels as a hearing threshold for low frequency sensitive marine 
mammals. This assumption was explained in ONR's DEIS.
    Comment 12: The AWI strongly objects to the issuance of permits 
that allow the intentional infliction of suffering on marine mammals, 
especially by the propagation of sound. AWI believes that NMFS cannot 
issue the permit knowing that the sound intensity will reach 195 dB, a 
sound intensity 55 dB louder than the sound known to cause neurological 
damage in human beings, who are not nearly as sensitive to sound as 
cetaceans.
    Response: The NPAL acoustic source operating at full intensity 
produces

[[Page 80820]]

approximately 260 Watts of acoustic power, resulting in a sound level 
of 195 dB re 1 micro Pa at one meter. NMFS does not believe that any 
marine mammals will be exposed to the source at this full intensity, 
since they would need to be immediately adjacent to the source, 807 m 
(2,648 ft) below the water surface during the 2-8 percent of the time 
the source was transmitting. This depth is approximately 550 m (1,804 
ft) deeper than the deepest recorded humpback whale dive depth, the 
only deep-diving marine mammal species expected to be commonly found in 
the offshore NPAL waters.
    Chapman and Ellis (1998) note that this comparison with humans is 
incorrect, for the following reasons: (1) The reference sound pressures 
used in underwater acoustics and in-air acoustics are not the same; (2) 
the statement compares a source level with a received level; and (3) 
there is no obvious connection between an annoying or harmful sound 
level for humans in air and an annoying or harmful sound level for a 
marine animal in water. NMFS recommends that reviewers unfamiliar with 
underwater acoustics read Appendix A of ONR's DEIS, and/or Richardson 
et al. (1995).
    Comment 13: Several comments noted that the DEIS and the Scripps 
application did not cite several scientific papers relating to whale 
stranding events. Other commenters expressed concern about sperm whales 
and beaked whales, two species that, in addition to humpback whales, 
are deep divers and sensitive to LF sounds.
    Response: NMFS and Scripps are unaware of any scientific reports 
regarding a relationship between transmissions of the ATOC source and 
marine mammal strandings in either California or Hawaii. Marine mammal 
stranding events elsewhere in the world that may be linked to acoustic 
noise, to date, have not been noted to be associated with LF sounds in 
the range of 60-90 Hz, but instead are more likely related to high 
intensity mid-frequency sounds. Please refer to the response to Comment 
2 for discussion on the Bahamian beaked whale stranding event.
    While audiograms are unavailable for beaked whales, they are 
believed to be mid-frequency hearers, not low-frequency hearers. 
Discussion on sperm whales, beaked whales, and other species and on the 
potential impact from the NPAL source on these species is provided in 
ONR's DEIS.
    Comment 14: One commenter states that the risk assumptions in this 
action rely on the same information provided to NMFS as justification 
for the planned LWAD Sea Test 00-2 off New Jersey. Those tests involved 
use of LF sonar devices. NMFS found justification insufficient to 
warrant NMFS concurrence with those tests and the Navy cancelled the 
acoustic portion of the tests.
    Response: On April 23, 2000, the U.S. Navy submitted to NMFS an 
Environmental Assessment (EA) for LWAD 00-2 and requested NMFS concur 
that these tests were unlikely to adversely affect species listed as 
threatened or endangered under the Endangered Species Act (ESA). NMFS 
responded on May 19 and May 26, 2000, that, because of the complexity 
of the project and the fact that the information provided in the EA was 
incomplete, NMFS could not concur with the Navy that the proposed 
action was not likely to adversely affect listed species under NMFS' 
jurisdiction. As a result, NMFS recommended that the Navy initiate 
formal consultation under section 7 of the ESA. Because there was 
insufficient time to complete formal consultation before the date the 
LWAD 00-2 Sea Test was scheduled to begin, the Navy cancelled the 
acoustic portion of the testing. NMFS finds no basis to conclude that 
the risk assumptions made for LWAD 00-2 were the same ones used for 
assessing marine mammal/sea turtle impacts for NPAL. Moreover, for the 
action under discussion in this document, ONR has requested formal 
consultation under section 7 of the ESA. That consultation will be 
completed prior to final determinations being made by ONR and Scripps 
on whether to proceed with its proposed action.

Mitigation Concerns

    Comment 15: The HSUS believes that authorizing the continued use of 
the sound source for the next 5 years with minimal mitigation is 
unwarranted and premature, especially with recent strandings and 
research strongly suggesting that some low to mid-frequency sounds can 
result in significant negative impacts to cetaceans.
    Response: It should be understood that NMFS does not authorize the 
activity, only the taking of marine mammals incidental to that 
activity. NMFS believes that the NPAL acoustic source, which at 75 Hz 
and 195 dB is significantly lower in frequency and intensity than those 
of many other sound sources in the world's oceans and is anchored in 
water depths of 807 m (2,648 ft), does not warrant comparison with 
open-water, mobile sources using loud mid-frequency sonars. The 
mitigation measures proposed for NPAL are listed in the application, 
the ONR's DEIS, and in this document. NMFS invites public comment on 
additional practical mitigation measures for this acoustic source 
located in deep water. NMFS also solicits comment on any relevant 
scientific information on impacts of LF sound on marine mammals, other 
than that cited in these documents. NMFS believes that the information 
obtained during the ATOC MMRP and the SURTASS LFA sonar Scientific 
Research Program (SRP) provide the best scientific information to date 
on this subject.
    Comment 16: The WDCS questioned mitigation measure 2 which stated 
that increases in duty cycle (of the NPAL's acoustic source) would not 
occur during the peak humpback whale breeding season, but that 
transmissions will be conducted during this season.
    Response: The NPAL acoustic source has been proposed to transmit on 
a 2-percent duty cycle. The proposed duty cycle would be six 20-minute 
transmissions (one every 4 hours), every fourth day, with each 
transmission preceded by a 5-minute ramp-up period. This is the minimum 
duty cycle necessary to support the large-scale acoustic thermometry 
and long-range propagation objectives. The 20-minute transmission 
period is designed to spread the energy over time, at much lower source 
levels, than if the signals were sent as short, loud pulses of the same 
total energy. However, the duty cycle may be increased to 8-percent for 
up to two months out of each year, to support short-term, long-range 
acoustic propagation studies. The 8 percent duty cycle would not occur 
during the humpback whale season (January-April). The rationale 
supporting the conduction of transmission studies during the humpback 
whale season is explained in detail in Chapter 2.1.3 of ONR's DEIS.
    Comment 17: The WDCS notes that, to its knowledge, there is no 
research that supports the statement that ``the five-minute ramp-up 
period would give all marine animals the opportunity to depart the 
immediate area of the source.''
    Response: NMFS recognizes that ramp-up may not be effective as a 
mitigation tool. However, NMFS notes that ramp-up is not the only 
mitigation measure proposed by the Navy and therefore, until such time 
as there is evidence that it is not effective, NMFS, Scripps, and ONR 
prefer to err on the side of caution and incorporate ramp-up into the 
mitigation program for NPAL's acoustic source.

[[Page 80821]]

Monitoring Concerns

    Comment 18: The MMC notes that the DEIS and the application 
indicate only that a total of four aerial surveys would be conducted 
each year in the period from January through April. There is no 
indication of how or by whom the aerial surveys would be conducted or 
what area(s) would be surveyed. The Hawaiian Islands Humpback Whale 
National Marine Sanctuary (HIHWNMS) recommends the four aerial surveys 
be augmented by at least two additional surveys to assess seasonal 
trends in abundance and distribution.
    Response: After review, Scripps now proposes to conduct eight 
surveys each year from February through early April, during the peak of 
the humpback whale season. In order to maintain a basis for comparison 
with previous aerial surveys conducted in the area off the north shore 
of Kauai, the proposed survey protocol would follow the protocol used 
in the earlier 1993-1998 surveys (see Mobley et al., 1999). The surveys 
would be scheduled eight days apart to match the NPAL transmission 
schedule. Based on an average of seven humpback sightings per survey 
observed during the 1998 season and assuming a moderate-sized effect 
due to NPAL transmissions, eight surveys should produce a minimum of 56 
sightings of humpback whales, which would result in an estimated power 
of 0.80 (i.e., there would be an 80-percent probability of detecting a 
change in distribution if an effect is present). The estimate of 56 
sightings is presumed to be a minimum, given previously reported 
evidence that Hawaiian wintering population of humpback whales is 
increasing.
    Comment 19: The MMC notes that there is no indication of the 
baseline information now available or the kinds of changes in 
distribution or abundance that would trigger a review and suspension or 
termination of the project.
    Response: Protocols similar to those used during the ATOC project 
would be followed for the review, suspension, and termination of the 
project. If at any time a monitoring team member identifies the 
occurrence of an acute or short-term effect on marine mammals, the 
information would be immediately communicated to the Team's Principal 
Investigator (PI). If the PI ascertains that an acoustic transmission 
coincided with the observed acute response, Scripps would suspend the 
source immediately and contact NMFS.
    In addition, NMFS and Scripps propose to coordinate closely with 
the Hawaiian stranding network and will investigate all strandings. 
While there is contradictory information in the comments received on 
this rulemaking regarding the level of competency of the local 
stranding network, NMFS believes that the location of the NPAL source 
allows for an acceptable level stranding response. If an investigation 
by NMFS of a stranding event indicated that the NPAL acoustic source 
was responsible for causing the event, NMFS would suspend the LOA until 
such time as the cause was corrected, or Scripps applied, and obtained 
a new LOA that would authorize the incidental taking of marine mammals 
by mortality. NMFS however, continues to believe that the NPAL source 
would result not in any marine mammal strandings.
    NMFS does not believe that the level of data from the monitoring 
program will allow determinations to be made that the NPAL acoustic 
source was responsible for any decreases in abundance of humpback 
whales or other marine mammals in the vicinity of the source. At this 
time, evidence indicates that the numbers of humpback whales and 
Hawaiian monk seals off Kauai are increasing, however, it is unclear 
whether this is due to total abundance increases or geographic shifts 
due to oceanographic changes. Similarly, a cause and effect between 
operation of the NPAL source and any decrease in abundance of marine 
mammals in the offshore Hawaiian Islands over the short-term period of 
5 years is unlikely.
    Comment 20: The HIHWNMS recommends boat-based surveys and, if 
possible, shore-based theodolite studies should be conducted. One 
citizen recommended additional aerial surveys year-round to assess 
impacts on dolphins and smaller whales.
    Response: Scripps notes that additional aerial surveys, boat-based 
surveys, and theodolite studies are not an efficient use of NPAL's 
resources and believes that this additional monitoring is unlikely to 
provide NMFS and the public with better data than would be provided by 
the humpback whale aerial surveys. Under current funding levels for 
this project, conducting these additional studies would necessitate a 
reduced aerial survey effort for humpback whales. NMFS notes that boat-
based surveys do not provide an encounter rate high enough to give 
statistically significant results. Theodolite studies, being shore 
based, are not near the NPAL source site, and therefore animals would 
show less reaction than animals closer to the source. While the 
proposed humpback whale aerial surveys will also detect other marine 
mammal species, because the smaller whales and dolphins are not 
expected to be sensitive (e.g., react) to the Kauai NPAL acoustic 
source transmission, NMFS does not believe that conducting additional 
aerial monitoring for these species is warranted.

Reporting Concerns

    Comment 21: The MMC recommends that any proposal to issue the 
requested authorization include a description of the proposed 
monitoring program, in sufficient detail, to enable reviewers to judge 
the likelihood that it will be capable of detecting biologically 
significant long-term effects in time to stop and reverse them.
    Response: A description of the monitoring program has been provided 
in this document.

MMPA Concerns

    Comment 22: The HSUS notes that the criterion of ``prolonged 
disturbance of biologically important behavior'' is not consistent with 
either Level A or Level B harassment in the MMPA. ``Prolonged 
disturbance'' is a criterion apparently invented for the purposes of 
this LOA request. It is of concern that applicants continue to create 
``take'' definitions inconsistent with the MMPA.
    Response: The NRC (2000) states that NMFS should promulgate uniform 
(noise) regulations based on their potential for a biologically 
significant impact on marine mammals. NMFS concurs. However, the term 
``prolonged,'' as used in ONR's DEIS and Scripps' application, implies 
an increase in time or duration beyond normal limits. This, NMFS 
believes, exceeds the criterion used by NMFS to note that harassment 
must refer to a reaction that is behaviorally significant on the part 
of the animal in the course of that animal's conducting a biologically 
important activity, such as breeding, feeding, migrating. In this 
context, it is the impact of the activity on the animal, not the 
duration of the disturbance, that is critical. NMFS requests additional 
comment on this criterion.
    By further clarifying Level B harassment as being more than a 
momentary reaction on the part of a marine mammal that has no 
consequence to the animal's survival or reproduction, NMFS believes 
that Scripps and ONR are in compliance with both the MMPA definition 
and NMFS' guidance for calculating takings of small numbers of marine 
mammals incidental to a maritime activity. NMFS believes that 
interpretation of the definition of Level B harassment to include 
trivial reactions like a change in breathing rates is inappropriate and 
would greatly increase the affected

[[Page 80822]]

universe of activities that would need to apply for small take 
authorizations under the MMPA, including the U.S. shipping, 
recreational boating, and ecotourism industries.
    Comment 23: The HSUS states that the concept that TTS is Level B 
harassment has seemingly been established de facto for some time now 
but never subject to public notice or comment. This is simply 
unacceptable, and in violation of the Administrative Procedure Act. The 
HSUS is disturbed at its continued appearance in documentation 
associated with Navy or ONR projects (such as the WINSTON S. CHURCHILL 
shock trial).
    Response: Because part of this rulemaking is the criterion NMFS 
proposes to use to determine levels of harassment incidental to takings 
of small number of marine mammals by the continued operation of a LF 
sound source previously installed off the north shore of Kauai by the 
ATOC project there is no violation of section 553(b) of the APA. NMFS 
invites comment on the criterion for assessing impacts from explosives 
on marine mammals.
    Comment 24: The AWI requests NMFS officially state its policy with 
regard to the requirement for researchers to apply for a small take 
permit if the levels of sound transmissions are under 180 dB. Do you 
currently require a permit if researchers subject marine mammals to 
Level B harassment? Does your agency currently consider sound of under 
180 dB insignificant and therefore exempt from an incidental take 
permit?
    Response: First, NMFS must clarify between different types of 
researchers. Researchers planning to conduct research directed at 
marine mammals need to apply for a scientific research permit under 
section 104 of the MMPA. This document does not discuss applications 
for scientific research under section 104 of the MMPA. Those 
researchers, and others, whose activity will have an incidental 
interaction with marine mammals can apply for a small take exemption 
under section 101(a)(5)(A) or (a)(5)(D) of the MMPA. That is the type 
of application under discussion in this document.
    Secondly, NMFS must clarify that there is a difference between a 
source level of 180 dB and a sound level of 180 dB received at the 
marine mammal. While NMFS considers that a received level at the marine 
mammal of 180 dB or greater has the potential to result in a taking of 
marine mammals, in most cases, an underwater acoustic device or 
instrument with a source level of 180 dB or less, is likely to 
attenuate (e.g., reduce in intensity) within a few meters to 
insignificant levels. Therefore, unless there is an abundance of marine 
mammals in close proximity to a source of this intensity, marine 
mammals are unlikely to be taken.
    In that regard, several factors need to be considered by a 
potential applicant prior to applying for a small take authorization. 
That person needs to consider: (1) The SPL and the frequency of the 
acoustic source (the higher the frequency, the greater the loss in 
intensity relative to distance); (2) whether the source results in an 
explosive, impulse, or intermittent noise; (3) the location and the 
duty cycle of the source; (4) the duration of the activity; and (5) the 
relative abundance of those species of marine mammals in the area of 
the source whose hearing range coincides with the frequencies of the 
acoustic source.
    However, it is the responsibility of the proponents of an activity 
to determine whether marine mammals will be harassed, injured, or 
killed by an activity. NMFS recommends that, if there is a potential 
for marine mammals to be harassed by an acoustic source and for the 
response on the part of the mammal(s) to be more than a simple alert, 
startle, or dive reaction, the responsible party should contact NMFS to 
ascertain whether a small take authorization should be obtained. NMFS 
believes that an animal simply hearing a noise and making a minor 
course correction to avoid the noise is not a behavioral reaction 
sufficient to warrant a small take application, provided the reaction 
does not result in a response on the part of the animal that is 
biologically significant. A biologically significant response is one 
that has the potential to affect reproduction and survival, including 
feeding and migration.
    Comment 25: One citizen wanted to know why NMFS is considering this 
(incidental harassment) proposal which potentially threatens to deprive 
the whale watching business of its vital coastal environment? Why 
should NMFS favor acoustic polluters over and above environmentally 
friendly businesses?
    Response: Under section 101(a)(5)(A) of the MMPA, NMFS is charged 
with determining that the total taking by a lawful maritime activity is 
having no more than a negligible impact on a small number of marine 
mammals. If that determination can be made, then an authorization can 
be issued (provided monitoring and reporting are carried out). However, 
because the Kauai MMRP demonstrated that no overt or obvious short-term 
change in abundance, distribution, or behavior of humpback whales 
occurred as a result of the ATOC sound transmissions, no direct effects 
on the economy through a reduction in whale-watching are expected to 
occur from operation of this source over the next 5 years.
    The intentional taking of marine mammals by whale watching and 
other recreational boating activities that seek out marine mammals for 
either business or personal enjoyment are an issue for discussion under 
NEPA. NMFS understands that the ONR FEIS will be expanded with new 
economic data on the tourism industry.
    Comment 26: The same citizen asks whether NMFS has considered the 
combined influences that these high intensity acoustic sources will 
create?
    Response: Unless one were also to consider vocalizing whales as 
being high intensity sources, NMFS does not believe that the NPAL 
source (at 195 dB) qualifies as a high intensity acoustic source. Under 
section 101(a)(5)(A) of the MMPA, NMFS is required to determine that 
the total taking by the specified activity is not having more than a 
negligible impact on affected marine mammal stocks. In this case, the 
specified activity under consideration is the operation of the NPAL 
acoustic source by Scripps. However, the cumulative impact on the 
marine environment from oceanic anthropogenic noise sources, such as 
Navy mid-frequency and LF sonars, commercial shipping, and recreational 
boating noise in the vicinity of Kauai, are subject to consideration by 
ONR in its EIS.

Other Concerns

    Comment 27: The HSUS noted that they and the Natural Resources 
Defense Council (NRDC) submitted extensive comments in October 1999 on 
the Navy's DEIS on SURTASS LFA sonar and its use of SURTASS LFA SRP 
data. The HSUS incorporates herein by reference concerns noted in those 
comments.
    Response: The proposed action in this document is the taking of 
marine mammals incidental to operation of the NPAL acoustic source that 
is stationary off Kauai, Hawaii, not the incidental taking of marine 
mammals by the world-wide deployment of SURTASS LFA sonar. Those 
comments will be addressed by the Navy in the FEIS for that activity. 
NMFS has reviewed the comments submitted by HSUS and the NRDC for the 
SURTASS LFA sonar DEIS and notes that most comments are not germane to 
this action.

Marine Mammals

    A summary of the marine mammal species that may potentially be 
found in

[[Page 80823]]

the vicinity of the NPAL acoustic source at either Kauai or Midway is 
presented here. For more detail on marine mammal abundance, density, 
and the methods used to obtain this information, reviewers are 
requested to refer to ONR's DEIS. For general information on North 
Pacific Ocean marine mammals, reviewers may refer to Barlow et al. 
(1997).
    Six species of baleen whales, humpback (Megaptera novaengliae), fin 
(Balaenoptera physalus), blue (B. musculus), Bryde's (B. edeni), minke 
(B. acutorostrata), and right (Eubalaena glacialis) whales, may occur 
in the Kauai or Midway Atoll areas. Although not reported near Midway 
Atoll, the humpback whale is the only balaenopterid whale known to be 
present in reasonably large numbers. Humpback whales are considered 
abundant in coastal waters of the main Hawaiian Islands from November 
through April. Fin whales and blue whales have the potential to occur 
in the area; however, their distribution and abundance in the region is 
believed to be uncommon (Balcomb, 1987), although only a single fin 
whale was observed during recent ATOC marine mammal research. Right 
whales in the North Pacific Ocean are extremely rare and therefore, 
would also be rare in the Hawaiian Islands. Bryde's whales, and minke 
whales may be occasionally seen in the area of Midway Atoll 
(Leatherwood et al., 1988), but are not usually found off Kauai.
    Sixteen species of odontocetes (toothed whales, dolphins and 
porpoises) may be found in the Kauai and Midway areas. These species 
are sperm whales (Physeter macrocephalus), short-finned pilot whales 
(Globicephala macrorhynchus), beaked whales (Ziphius cavirostris, 
Berardius bairdi, and Mesoplodon spp.), spinner dolphins (Stenella 
longirostris), spotted dolphins (Stenella attenuata), striped dolphins 
(Stenella coeruleoalba), bottlenose dolphins (Tursiops truncatus), 
rough-toothed dolphins (Steno bredanensis), pygmy sperm whales (Kogia 
breviceps), dwarf sperm whales (Kogia simus), killer whales (Orcinus 
orca), false killer whales (Pseudorca crassidens), pygmy killer whales 
(Feresa attenuata), and melon-headed whales (Peponocephala electra). It 
should be noted, however, that the latter 7 species were not sighted in 
or near the proposed Kauai area during marine mammal surveys conducted 
between 1993 and 1998.
    The Hawaiian monk seal (Monachus schauinslandi) occurs in the area 
of the Leeward Hawaiian Islands and, more recently in the main Hawaiian 
Islands, including the island of Kauai.

Potential Impacts on Marine Mammals

    The effects of underwater noise on marine mammals are highly 
variable, and can be categorized as follows (based on Richardson et 
al., 1995): (1) The noise may be too weak to be heard at the location 
of the animal (i.e. lower than the prevailing ambient noise level, the 
hearing threshold of the animal at relevant frequencies, or both); (2) 
the noise may be audible but not strong enough to elicit any overt 
behavioral response; (3) the noise may elicit behavioral reactions of 
variable conspicuousness and variable relevance to the well being of 
the animal; these can range from subtle effects on respiration or other 
behaviors (detectable only by statistical analysis) to active avoidance 
reactions; (4) upon repeated exposure, animals may exhibit diminishing 
responsiveness (habituation), or disturbance effects may persist (the 
latter is most likely with sounds that are highly variable in 
characteristics, unpredictable in occurrence, and associated with 
situations that the animal perceives as a threat); (5) any man-made 
noise that is strong enough to be heard has the potential to reduce 
(mask) the ability of marine mammals to hear natural sounds at similar 
frequencies, including calls from conspecifics and/or echolocation 
sounds, and environmental sounds such as ice or surf noise; and (6) 
very strong sounds have the potential to cause either a temporary or a 
permanent reduction in hearing sensitivity (i.e., TTS or PTS, 
respectively). Few data on the effects of non-explosive sounds on 
hearing thresholds of marine mammals have been obtained; however, in 
terrestrial mammals, and presumably in marine mammals, received sound 
levels must far exceed the animal's hearing threshold for there to be 
any TTS. Received levels must be even higher for there to be risk of 
PTS. In this proposed action, a marine mammal would have to receive one 
ping greater than, or equal to 180 dB in order to be considered 
receiving a non-serious injury, or many pings at an RL slightly lower 
than 180 dB in order to potentially incur a significant biological 
response (Level B harassment).
    In order to understand the biological significance of the risk of 
Level A or Level B harassment, it is necessary to determine how this 
risk might affect a population of marine mammals, starting with 
acoustic criteria. First, the marine mammal must be able to hear LF 
sound. Second, the animal must incur a reaction to the LF sound that is 
more than momentary. Third, any effect from LF sound must involve a 
significant behavioral change in a biologically important activity, 
such as feeding, breeding, or migration, all of which are potentially 
important for reproductive success of the population.
    Based on California and Hawaii ATOC MMRPs, Scripps found no overt 
or obvious short-term changes: (1) In the abundance and distribution of 
marine mammals in response to the ATOC transmissions (intensive 
statistical analyses of aerial survey data showed some subtle shifts in 
distribution of humpback (and possibly sperm) whales away from the 
California site (Calambokidis et al., 1998) and humpback whales away 
from the Kauai site); (2) in the behavior of humpback whales in 
response to the playback of ATOC-like sounds (intensive statistical 
analyses revealed some subtle changes in the behavior of humpback 
whales (Frankel and Clark, 1998; 1999b); or (3) in the singing behavior 
of humpback whales in the vicinity of the Kauai ATOC sound source. 
Bioacoustic experts concluded that these subtle effects would not 
adversely affect the survival of an individual whale or the status of 
the North Pacific humpback whale population (Frankel and Clark, 1999a).
    To assess the potential environmental impact of the NPAL sound 
source on marine mammals, it was necessary for Scripps to predict the 
sound field that a given marine mammal species could be exposed to over 
time. This is a multi-part process involving (1) the ability to measure 
or estimate an animal's location in space and time, (2) the ability to 
measure or estimate the three-dimensional sound field at these times 
and locations, (3) the integration of these two data sets to estimate 
the potential impact of the sound field on a specific animal in the 
modeled population, and (4) the conversion of the resultant cumulative 
exposures for a modeled population into an estimate of the risk from a 
disruption of a biologically important behavior.
    Next, a relationship for converting the resultant cumulative 
exposures for a modeled population into an estimate of the risk to the 
entire population of a significant disruption of a biologically 
important behavior and of injury was developed. This process assessed 
risk in relation to RL and repeated exposure. The resultant ``risk 
continuum'' is based on the assumption that the threshold of risk is 
variable and occurs over a range of conditions rather than at a single 
threshold.
    Taken together, the recent results on marine mammals from LF 
sounds, the

[[Page 80824]]

acoustical modeling, and the risk assessment, provide an estimate of 
potential environmental impacts to marine mammals.
    The acoustical modeling process was accomplished by Scripps using 
the U.S. Navy's standard acoustical performance prediction transmission 
loss model-Parabolic Equation (PE) version 3.4. The results of this 
model are the primary input to the AIM model. AIM was used in this 
analysis to estimate mammal sound exposures and integrate simulated 
characteristics of marine mammals (e.g., species distribution, density, 
dive profiles, and general movement, NPAL sound transmissions (e.g., 
duty cycle, transmission length), and the predicted sound field for 
each transmission to estimate acoustic exposure during a typical NPAL 
source transmission. A description of the PE and AIM models (including 
AIM input parameters for animal movement, diving behavior, and marine 
mammal distribution, abundance, and density) and the risk continuum 
analysis are described in detail in the Scripps application and ONR's 
DEIS and are not discussed further in this document. At this time, NMFS 
recommends reviewers read these documents if additional information is 
desired.
    Scripps has drawn some general conclusions from the relative 
abundance of various marine mammal species in relationship to the NPAL 
sound field. Under the proposed alternative (utilizing the ATOC sound 
source at Kauai), the only mysticete (baleen) whale species expected in 
the area in substantial numbers is the humpback whale, and Scripps 
believes that because they usually prefer nearshore locations (inside 
the 100-fathom (188 m) depth contour), few are expected to be exposed 
to received levels greater than 120 dB (i.e, the SPL level presumed by 
Scripps to be zero for marine mammals having the potential to incur 
significant disturbance of biologically important behavior). Similarly, 
sperm whales are the most common deep-diving odontocete (toothed) whale 
in the area, but because they usually prefer offshore waters (i.e., 
water depths greater than 4,000 m (12,700 ft)), few are expected to be 
exposed to received levels greater than 120 dB. According to Scripps, 
these distributional preferences are supported by the Kauai ATOC MMRP 
(Mobley, 1999a).
    Using the risk continuum and acoustic modeling, Scripps estimated 
the potential for biologically significant reactions by marine mammals 
under the proposed action. Scripps determined that only humpback whales 
that remain in the vicinity of the sound source for a full day of 
transmissions may potentially experience any effect from the source 
transmissions. However, humpback whales typically travel parallel to 
the coast of Kauai, and, therefore, Scripps believes, would probably 
not receive sound from more than a single transmission.
    At the Midway site, the mysticete whale expected in greatest 
abundance is the Bryde's whale. Because they usually prefer nearshore 
locations, Scripps expects few animals would be exposed to RLs greater 
than 120 dB. Similarly, sperm whales are the most common deep-diving 
odontocetes in the area, but because they usually prefer offshore 
waters (i.e., water depths greater than 4,000 m (12,700 ft)), few are 
expected to be exposed to received levels greater than 120 dB.
    A much higher abundance of Hawaiian monk seals is expected near 
Midway Island than Kauai since this species prefers the small, mostly 
uninhabited chain of islands and atolls northwest of the main Hawaiian 
Islands.
    Using the risk continuum and acoustic modeling Scripps determined 
that there would be no potential for biologically significant effects 
on marine mammals from source transmissions at Midway Island, although 
some subtle effects may occur.

Mitigation

    Scripps' proposed action includes mitigation that would minimize 
the potential effects of the NPAL sound source to marine mammals. 
First, the sound source would operate at the minimum duty cycle 
necessary to support the large-scale acoustic thermometry and long-
range propagation objectives. Transmissions would continue with 
approximately the same transmission schedule as that used during the 
first feasibility phase of the ATOC study. Second, any increases in the 
duty cycle beyond the nominal 2 percent (with a maximum of 8 percent) 
would not occur during the humpback whale season (January-April). The 
proposed action includes the possibility of an 8-percent duty cycle for 
up to 2 months out of each year; this action, however, would not occur 
during the period of time humpback whales inhabit Hawaiian waters. 
Third, the sound source would operate at the minimum power level 
necessary to support large-scale acoustic thermometry and long-range 
sound transmission objectives. The fourth mitigation measure proposed 
is to ramp-up the NPAL sound source transmissions over a 5-min period. 
This is believed to reduce the potential for startling marine mammals 
in the vicinity of the NPAL sound source and provides them an 
opportunity to move away from the sound source before transmitting at 
the maximum power levels.

Monitoring and Reporting

    In an effort to understand the potential for long-term effects of 
man-made sound on marine mammals, Scripps proposes to monitor the 
distribution and abundance of marine mammals in the vicinity of the 
sound source by conducting eight surveys each year from February 
through early April. In order to maintain a basis for comparison with 
previous aerial surveys conducted in the area off the north shore of 
Kauai, the proposed survey protocol would follow the protocol used in 
the earlier 1993-1998 surveys (see Mobley et al., 1999). The surveys 
would be scheduled eight days apart to match the NPAL transmission 
schedule. Based on an average of seven humpback sightings per survey 
observed during the 1998 season, and assuming a moderate sized effect 
due to NPAL transmissions, eight surveys should produce a minimum of 56 
sightings of humpback whales, which would result in an estimated power 
of 0.80 (i.e., there would be an 80- percent probability of detecting a 
change in distribution if an effect is present). The estimate of 56 
sightings is presumed to be a minimum, given previously reported 
evidence that Hawaiian wintering population of humpback whales is 
increasing. Reports on the aerial survey results will be available to 
the public in reports. A report on activities will be provided to NMFS 
annually upon the conclusion of that year's aerial surveys.

Preliminary Determinations

    Based on the scientific analyses detailed in Scripps' application 
and further supported by information and data contained in ONR's DEIS, 
NMFS concurs with Scripps and ONR that the incidental harassment of 
marine mammals incidental to the continued operation of an LF acoustic 
source previously installed off the north shore of Kauai by the ATOC 
project would result in only small numbers (as the term is defined in 
Sec.  216.103) of marine mammals being taken, have no more than a 
negligible impact on the affected marine mammal stocks or habitats and 
not have an unmitigable adverse impact on Arctic subsistence uses of 
marine mammals.
    In addition to the mitigation measures described previously, the 
following factors need to be considered when determining whether the 
taking by the NPAL acoustic source would be negligible: (1) The limited 
duty cycle of

[[Page 80825]]

the source (2-8 percent); (2) the information that most species of 
marine mammals are relatively insensitive to acoustic sounds as low as 
the NPAL source; (3) the fact that relatively few marine mammals that 
inhabit the acoustic source area that are known to dive to depths that 
would put them in the proximity to sound fields that could disrupt 
biologically significant behavior; and (4) the low potential for a 
marine mammal actually being within the acoustic sound field during 
sonar transmissions. In consideration of these factors, NMFS 
preliminarily concludes that the operation of the acoustic source at 
Kauai (or Midway) would result in no more than small numbers of marine 
mammals being affected, and that the proposed action would have a 
negligible impact on affected marine mammal species and stocks.

NEPA

    The ONR has released a DEIS under NEPA (see ADDRESSES). The comment 
period for that document ended on July 24, 2000. NMFS is a cooperating 
agency, as defined by the Council on Environmental Quality (40 CFR 
1501.6), in the preparation of this DEIS and the Final EIS, currently 
under preparation.

Endangered Species Act (ESA)

    NMFS is in consultation with the ONR under section 7 of the ESA on 
this action. In that regard, the ONR has submitted to NMFS a Biological 
Assessment under the ESA. This consultation will be concluded prior to 
a determination on the issuance of a final rule and LOA.

Costs and Benefits

    In addition to allowing Scripps to take a small number of marine 
mammals incidental to conducting scientific research using the NPAL 
acoustic source off Hawaii, this rule would require Scripps to provide 
NMFS and the public with information on the NPAL source's effect on 
certain species of marine mammals. Without an authorization under the 
MMPA, NMFS and the public may not receive this information. NMFS 
believes that obtaining this information is important because 
scientific findings resulting from the monitoring program is likely to 
be directly applicable to other oceanographic research activities that 
employ LF acoustic sources. The cost to ONR and Scripps cannot be fully 
determined at this time but these costs would be incurred through 
implementation of the aerial monitoring program that will be required 
under this proposed rule. Preliminarily, NMFS believes that this cost 
would be approximately $ 300,000 during the 5-year program.

Information Solicited

    NMFS requests interested persons and organizations to submit 
comments, information, and suggestions concerning the content of the 
proposed regulations to authorize the taking. All commenters are 
requested to review the application prior to submitting comments and 
not submit comments solely on this Federal Register document. Because 
the comment period on the draft EIS has ended, comments on issues not 
relevant to either the potential impact of the NPAL acoustic source on 
marine mammals or NMFS' responsibilities under the MMPA will not be 
considered.

Classification

    This action has been determined to be not significant for purposes 
of Executive Order 12866.
    The Assistant General Counsel for Legislation and Regulation of the 
Department of Commerce has certified to the Chief Counsel for Advocacy 
of the Small Business Administration that this proposed rule, if 
adopted, would not have a significant economic impact on a substantial 
number of small entities since it would apply only to Scripps and would 
have no effect, directly or indirectly, on small businesses. It will 
also affect a small number of contractors providing services related to 
reporting the impact of the NPAL source on marine mammals. Some of the 
affected contractors may be small businesses, but the number involved 
would not be substantial. Further, since the monitoring and reporting 
requirements are what would lead to the need for their services, the 
economic impact on them would be beneficial. Because of this 
certification, a regulatory flexibility analysis is not required.
    Notwithstanding any other provision of law, no person is required 
to respond to nor shall a person be subject to a penalty for failure to 
comply with a collection of information subject to the requirements of 
the Paperwork Reduction Act (PRA) unless that collection of information 
displays a currently valid OMB control number. This proposed rule 
contains collection-of-information requirements subject to the 
provisions of the PRA. This collection has been approved previously by 
OMB under section 3504(b) of the PRA issued under OMB control number 
0648-0151. These requirements include an application for an LOA and an 
annual report on monitoring. Other information requirements in the rule 
are not subject to the PRA since they apply only to a single entity 
and, therefore, are not contained in a rule of general applicability.
    The reporting burden for this collection is estimated to be 
approximately 80 hours, including the time for gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information. It does not include time for monitoring the 
activity.

List of Subjects in 50 CFR Part 216

    Administrative practice and procedure, Imports, Indians, Marine 
mammals, Penalties, Reporting and recordkeeping requirements, 
Transportation.

    Dated: December 15, 2000.
William T. Hogarth,
Deputy Assistant Administrator for Fisheries, National Marine Fisheries 
Service.

    For reasons set forth in the preamble, 50 CFR part 216 is proposed 
to be amended as follows:

PART 216--REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE 
MAMMALS

    1. The authority citation for part 216 continues to read as 
follows:

    Authority: 16 U.S.C. 1361 et seq.

    2. Subpart P is added to read as follows:

Subpart P--Taking of Marine Mammals Incidental to Operating A Low 
Frequency Acoustic Source by the North Pacific Acoustic Laboratory

Sec.
216.170  Specified activity and specified geographical region.
216.171  Effective dates.
216.172  Permissible methods of taking.
216.173  Prohibitions.
216.174  Mitigation.
216.175  Requirements for monitoring and reporting.
216.176  Letter of Authorization.
216.177  Renewal of a Letter of Authorization.
216.178  Modifications to a Letter of Authorization.

Subpart P--Taking of Marine Mammals Incidental to Operating A Low 
Frequency Acoustic Source by the North Pacific Acoustic Laboratory


Sec. 216.170  Specified activity and specified geographical region.

    (a) Regulations in this subpart apply only to the incidental taking 
of small numbers of marine mammals specified in paragraph (b) of this 
section by U.S. citizens engaged in conducting acoustic research using 
a moored, low-frequency acoustic source by the North Pacific

[[Page 80826]]

Acoustic Laboratory off either Kauai or Midway Islands, Hawaii.
    (b) The incidental harassment of marine mammals under the activity 
identified in paragraph (a) of this section is limited to small numbers 
of the following species: humpback whales (Megaptera novaengliae), fin 
whales (Balaenoptera physalus), blue whales (B. musculus), Bryde's 
whales (B. edeni), minke whales (B. acutorostrata), North Pacific right 
whales (Eubalaena glacialis), sperm whales (Physeter macrocephalus), 
short-finned pilot whales (Globicephala macrorhynchus), beaked whales 
(Ziphius cavirostris, Berardius bairdi, and Mesoplodon spp.), spinner 
dolphins (Stenella longirostris), spotted dolphins (Stenella 
attenuata), striped dolphins (Stenella coeruleoalba), bottlenose 
dolphins (Tursiops truncatus), rough-toothed dolphins (Steno 
bredanensis), pygmy sperm whales (Kogia breviceps), dwarf sperm whales 
(Kogia simus), killer whales (Orcinus orca), false killer whales 
(Pseudorca crassidens), pygmy killer whales (Feresa attenuata), and 
melon-headed whales (Peponocephala electra). and Hawaiian monk seals 
(Monachus schauinslandi).


Sec. 216.171  Effective dates.

    Regulations in this subpart are effective from April 1, 2001, 
through March 31, 2006.


Sec. 216.172  Permissible methods of taking.

    (a) Under a Letter of Authorization issued pursuant to 
Secs. 216.106 and 216.176, the Holder of this Letter of Authorization 
may incidentally, but not intentionally, take marine mammals by 
harassment within the area described in Sec. 216.170(a), provided the 
activity is in compliance with all terms, conditions, and requirements 
of these regulations and the Letter of Authorization.
    (b) The activities identified in Sec. 216.170(a) must be conducted 
in a manner that minimizes, to the greatest extent practicable, any 
adverse impacts on marine mammals and their habitat.


Sec. 216.173  Prohibitions.

    Notwithstanding takings authorized by Sec.  216.170(b) and by a 
Letter of Authorization issued under Secs. 216.106 and 216.176, no 
person in connection with the activities described in Sec. 216.170(a) 
shall:
    (a) Take any marine mammal not specified in Sec.  216.170(b);
    (b) Take any marine mammal specified in Sec.  216.170(b) other than 
by incidental, unintentional harassment;
    (c) Take a marine mammal specified in Sec.  216.170(b) if such take 
results in more than a negligible impact on the species or stocks of 
such marine mammal; or
    (d) Violate, or fail to comply with, the terms, conditions, and 
requirements of these regulations or a Letter of Authorization issued 
under Secs. 216.106 and 216.176.


Sec.  216.174  Mitigation.

    As described in the Letter of Authorization issued under Secs.  
216.106 and 216.176, the North Pacific Acoustic Laboratory acoustic 
source must:
    (a) Operate at the minimum duty cycle necessary for conducting 
large-scale acoustic thermometry and long-range propagation objectives.
    (b) Not increase its duty cycle for long-range propagation studies 
during the months of January through April.
    (c) Operate at the minimum power level necessary for conducting 
large-scale acoustic thermometry and long-range propagation objectives.
    (d) Precede all transmissions from the acoustic source by a 5-
minute ramp-up of the acoustic source's power.


Sec. 216.175  Requirements for monitoring and reporting.

    (a) The holder of the Letter of Authorization is required to 
cooperate with the National Marine Fisheries Service and any other 
Federal, state or local agency monitoring the impacts of the activity 
on marine mammals. The holder must notify the Southwest Regional 
Administrator at least 2 weeks prior to commencing monitoring 
activities.
    (b) The Holder of this Authorization must conduct a minimum of 
eight surveys each year from February through early April in the area 
off the north shore of Kauai, Hawaii.
    (c) The Holder of this Authorization must, through coordination 
with marine mammal stranding networks in Hawaii, monitor strandings of 
marine mammals to detect long-term trends in stranding and the 
potential relationship to the North Pacific Acoustic Laboratory 
acoustic source.
    (d) Activities related to the monitoring described in paragraphs 
(b) and (c) of this section, or in the Letter of Authorization issued 
under Secs. 216.106 and 216.176 may be conducted without the need for a 
separate scientific research permit.
    (e) In coordination and compliance with marine mammal researchers 
operating under this subpart, at its discretion, the National Marine 
Fisheries Service may place an observer on any aircraft involved in 
marine mammal surveys in order to monitor the impact on marine mammals.
    (f) The holder of a Letter of Authorization must annually submit a 
report to the Director, Office of Protected Resources, National Marine 
Fisheries Service, no later than 120 days after the conclusion of 
humpback whale aerial survey monitoring program. This report must 
contain all the information required by the Letter of Authorization, 
including the results, if any, of coordination with coastal marine 
mammal stranding networks.
    (g) A final comprehensive report must be submitted to the Director, 
Office of Protected Resources, National Marine Fisheries Service no 
later than 240 days after completion of the final year of humpback 
whale aerial survey monitoring conducted under Sec. 216.175. This 
report must contain all the information required by the Letter of 
Authorization.


Sec. 216.176  Letter of Authorization.

    (a) A Letter of Authorization, unless suspended or revoked, will be 
valid for a period of time specified in the Letter of Authorization but 
may not exceed the period of validity of this subpart.
    (b) A Letter of Authorization with a period of validity less than 
the period of validity of this subpart may be renewed subject to 
renewal conditions in Sec. 216.177.
    (c) A Letter of Authorization will set forth:
    (1) Permissible methods of incidental taking;
    (2) Authorized geographic area for taking;
    (3) Means of effecting the least practicable adverse impact on the 
species of marine mammals authorized for taking and its habitat; and
    (4) Requirements for monitoring and reporting incidental takes.
    (d) Issuance of a Letter of Authorization will be based on a 
determination that the number of marine mammals taken by the activity 
will be small, and that the number of marine mammals taken by the 
activity, specified in Sec.  216.170(b), as a whole will have no more 
than a negligible impact on the species or stocks of affected marine 
mammal(s).
    (e) Notice of issuance or denial of a Letter of Authorization will 
be published in the Federal Register within 30 days of a determination.


Sec. 216.177  Renewal of a Letter of Authorization.

    (a) A Letter of Authorization issued under Sec. 216.106 and Sec.  
216.176 for the activity identified in Sec. 216.170(a) will be renewed 
upon:
    (1) Notification to the National Marine Fisheries Service that the 
activity described in the application for a Letter of Authorization 
submitted under

[[Page 80827]]

Sec. 216.176 will be undertaken and that there will not be a 
substantial modification to the described work, mitigation or 
monitoring undertaken during the upcoming season;
    (2) Timely receipt of the monitoring reports required under 
Sec. 216.175, which have been reviewed by the National Marine Fisheries 
Service and determined to be acceptable;
    (3) A determination by the National Marine Fisheries Service that 
the mitigation, monitoring and reporting measures required under 
Secs. 216.174 and 216.175 and the Letter of Authorization were 
undertaken and will be undertaken during the upcoming period of 
validity of a renewed Letter of Authorization; and
    (4) Renewal of a Letter of Authorization will be based on a 
determination that the number of marine mammals taken by the activity 
continues to be small, and that the number of marine mammals taken by 
the activity, specified in Sec. 216.170(b) will have no more than a 
negligible impact on the species or stock of affected marine mammal(s).
    (b) A notice of issuance or denial of a renewal of a Letter of 
Authorization will be published in the Federal Register within 30 days 
of a determination.


Sec. 216.178  Modifications to a Letter of Authorization.

    (a) In addition to complying with the provisions of Secs. 216.106 
and 216.176, except as provided in paragraph (b) of this section, no 
substantive modification (including withdrawal or suspension) to the 
Letter of Authorization issued pursuant to Secs. 216.106 and 216.176 
and subject to the provisions of this subpart shall be made by the 
National Marine Fisheries Service until after notification and an 
opportunity for public comment has been provided. For purposes of this 
paragraph, a renewal of a Letter of Authorization under Sec. 216.177, 
without modification, except for the period of validity is not 
considered a substantive modification.
    (b) If the Assistant Administrator determines that an emergency 
exists that poses a significant risk to the well-being of the species 
or stocks of marine mammals specified in Sec. 216.170(b), a Letter of 
Authorization issued pursuant to Secs. 216.106 and 216.176 may be 
substantively modified without prior notification and an opportunity 
for public comment. Notification will be published in the Federal 
Register within 30 days subsequent to the action.
[FR Doc. 00-32725 Filed 12-21-00; 8:45 am]
BILLING CODE 3510-22-S