[Federal Register Volume 61, Number 61 (Thursday, March 28, 1996)]
[Notices]
[Pages 13847-13851]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-7624]



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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
[I.D. 032296A]


Small Takes of Marine Mammals Incidental to Specified Activities; 
Haro Strait Oceanographic Experiment

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

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

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SUMMARY: NMFS has received a request from Prof. Henrik Schmidt of the 
Department of Engineering, Massachusetts Institute of Technology (DE/
MIT), Cambridge, MA, for

[[Page 13848]]
authorization to take small numbers of marine mammals by harassment 
incidental to conducting a physical oceanography experiment that uses 
sound to study the flow field and mixing processes in Haro Strait, 
Puget Sound, WA. Under the Marine Mammal Protection Act (MMPA), NMFS is 
requesting comments on its proposal to authorize DE/MIT to incidentally 
take, by harassment, small numbers of marine mammals in the above-
mentioned area between June 10, 1996, and July 5, 1996.

DATES: Comments and information must be received on or before April 29, 
1996.

ADDRESSES: Comments on the application should be addressed to Chief, 
Marine Mammal Division, Office of Protected Resources, National Marine 
Fisheries Service, 1315 East-West Highway, Silver Spring, MD 20910-
3225. A copy of the application, a list of references used in this 
document, and/or a programmatic Environmental Assessment (EA) may be 
obtained by writing to this address or by telephoning one of the 
contacts listed below.

FOR FURTHER INFORMATION CONTACT: Kenneth Hollingshead, Office of 
Protected Resources at 301-713-2055, or Brent Norberg, Northwest 
Regional Office at 206-526-6733.

SUPPLEMENTARY INFORMATION:

Background

    Section 101(a)(5)(A) of the MMPA (16 U.S.C. 1361 et seq.) directs 
NMFS 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 regulations are 
issued.
    Permission may be granted if NMFS finds that the taking will have a 
negligible impact on the species or stock(s); will not have an 
unmitigable adverse impact on the availability of the species or 
stock(s) for subsistence uses; and the permissible methods of taking 
and requirements pertaining to the monitoring and reporting of such 
taking are set forth.
    On April 30, 1994, the President signed Public Law 103-238, the 
MMPA Amendments of 1994. One part of this law added a new subsection 
101(a)(5)(D) to the MMPA to establish 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 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.

    New 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 31, 1996, NMFS received a complete application from DE/
MIT requesting an authorization for the harassment of small numbers of 
marine mammals incidental to conducting a physical oceanography 
experiment that uses sound to study the flow field and mixing processes 
in Haro Strait, in the San Juan Island Archipelago (Puget Sound) WA, 
just south of Stuart Island (48 deg.39'00'' N, 123 deg.11'00'' W).
    The experiment, which will be from June 10 through July 5, 1996, 
for a total of 26 days, is scheduled to take advantage of the extreme 
ebb tides that occur only twice a year. The winter alternative is 
unacceptable, because weather conditions at that time of the year would 
make operations extremely difficult and would make marine mammal 
monitoring virtually impossible.
    As described in the application, the experiment consists of three 
primary components: (1) A vertical array system, which consists of 5 
vertical arrays that will be permanently moored to the bottom 
throughout the experiment; (2) two autonomous underwater vehicles 
(AUVs), which will be deployed for about 4 hours per day during maximum 
front formation. The AUVs are equipped for salinity, temperature and 
pressure sensing and have sound sources for acoustic modem 
communications as well as tomography sources; and (3) a set of drifters 
that will move with the flow field and map current speed profiles using 
Doppler-shift sonar methods. All systems will be integrated using the 
Autonomous Oceanographic Sampling Network (AOSN). Additional 
information on the experiment is available in the application. 
Information on the sound sources to be used during this experiment are 
provided in Table 1 of this notice.
    Source D (the Long-Base-Line (LBL) transponder array) will be 
deployed on June 10 and will be operated (along with source E) for 4 
hours/day until the end of the experiment. The vertical arrays will be 
deployed on June 11, and sources A, B, and C will operate daily from 
June 11 until the end of the experiment. Sources F and G will be used 
in conjunction with the AUVs on a few days before June 24 and will be 
used daily for 4 hours after June 24. Sources H and I, which are the 
Institute of Ocean Science's (IOS) side-scan sonars, will be used for 4 
hours/day from June 23 until the end of the experiment on July 5, 1996.

                                       Table 1.--List of Sound Sources To Be Used in the Haro Strait experiment\1\                                      
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                                                                Amplitude (dB                                                                           
             Source                    Class        Frequency    re 1Pa)          (seconds(s))                                                         
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Modems.........................  A                   13-18               170   2 s.                 1/min..............  5-moor............           30
Tomography.....................  B                     1-2               170   1 s.                 1/min..............  5-moor............           50
Array tracking.................  C                   25-30               160   0.1 s.               1/min..............  5-moor............          200
LBL transponders...............  D                    8-12               192   0.01 s.              10 sec.............  4/5 trns/ship.....        100/7
Ultra short-baseline             E                   18-22               184   0.001 s.             10 sec.............  ship and AUV......  ...........
 transponders.                                                                                                                                          
LF ADCP \2\....................  F                 115-125               194   0.0001 s.            5 sec..............  1 AUV.............           50
HF ADCP \3\....................  G                 295-305               194   0.0001 s.            5 sec..............  1 AUV.............           50
IOS imaging \4\................  H                  90-110               195   0.0001               0.2 sec............  1 AUV.............           30
IOS drifter \4\................  I                  90-110               195   0.0001/10s           0.2 sec............  1 AUV.............           30

[[Page 13849]]
                                                                                                                                                        
Low frequency tomography.......  J                0.06-0.3               160   1 s.                 10 sec.............  ship..............          10 
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\1\ Note that some sources are produced out of more than one transducer.                                                                                
\2\ Low frequency Doppler-shift current profiler.                                                                                                       
\3\ High frequency Doppler-shift current profiler.                                                                                                      
\4\ Side-scan Doppler-shift sonar onboard the AUVs (imaging) or the drifter.                                                                            


    The low-frequency tomography source (source J) will be used for 4 
hours/day from June 18-June 20, 1996.

Description of Marine Mammals Affected by the Activity

    The species of marine mammals that are likely to be present in the 
affected area at the time of the experiment include the harbor porpoise 
(Phocoena phocoena), killer whale (Orcinus orca), Dall's porpoise 
(Phocoenoides dalli), and harbor seal (Phoca vitulina). Additional 
species that are rare or only occasionally seen in the area at the time 
of the experiment include: Minke whale (Balaenoptera acutorostrata), 
elephant seal (Mirounga angustirostris); Pacific white-sided dolphin 
(Lagenorhynchus obliquidens), northern sea lion (Eumetopias jubatus), 
California sea lion (Zalophus californianus), humpback whale (Megaptera 
novaengliae), and gray whale (Eschrichtius robustus). General 
information on these species can be found in Barlow et al. (1995) 
5. More specific information on marine mammals species in Puget 
Sound waters can be found in the application, which is available upon 
request (see ADDRESSES), and does not need to be repeated here.

    \5\  A list of references used in this document can be obtained 
by writing to the address provided above (see ADDRESSES).
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Potential Effects on Marine Mammals

    The potential effects on marine mammals from sounds transmitted 
into the water include harassment, temporary or permanent hearing loss, 
and short-term habitat displacement. The most severe effect can be 
death or permanent hearing loss, with less severe effects including 
pain, masking of communication or echolocation signals, habitat 
avoidance, increased stress, and behavioral or social disruption 
(Richardson et al. 1991 as cited in the application). Of these 
reactions, permanent hearing loss and habitat exclusion are the primary 
effects that have the possibility of causing injury to an animal or 
group of animals. As detailed below, for the Haro Strait experiment, 
hearing loss is extremely unlikely, because sources' amplitudes are not 
high enough to cause damage except at extremely close distances (< 1 
m). The amount of habitat that may be excluded is likely to be small in 
comparison to the total range of these animals, and any observed 
harmful effects can be mitigated with an effective monitoring plan 
(described below), which will be in place prior to beginning the 
experiment.

Permanent Hearing Loss

    In humans and other terrestrial mammals, permanent hearing loss may 
occur from exposure to very loud transient sounds. Lengthy exposure to 
lower amplitude sounds can also cause permanent hearing loss 
(Richardson et al. 1995). However, none of the sources listed in Table 
1 is considered a continuous source. In humans and other terrestrial 
animals, an impulsive sound with a received sound level of 155 to 160 
dB above absolute hearing thresholds may cause permanent hearing damage 
(Greenlaw 1987, Kryter 1985). While it is unknown if similar levels 
cause damage in marine mammals (Richardson et al. 1991, 1995), until 
better information is available for marine mammals, NMFS proposes to 
adopt this level as the onset of permanent hearing damage in marine 
mammals. NMFS clarifies, however, that both the source and the marine 
mammal's hearing need to be within the same frequency for this damage 
to potentially take place.
    Using 155 dB above hearing threshold as a first approximation of 
the received level required for permanent hearing damage in marine 
mammals, the applicant calculated a radius within which each source 
(listed in Table 1 of this notice) might affect permanent hearing loss 
for those three species present in the area for which data is available 
(harbor porpoise/Dall's porpoise, harbor seal, and killer whale). 
Calculations indicate that marine mammals would need to be closer than 
.25 m to source D in order to potentially receive hearing damage; for 
other sources, animals would need to be even closer (please refer to 
Table 3 in the application for actual distances). However, the 
applicant presumes that the near-field effects might cause the distance 
to be slightly greater (but less than 1 m, than calculated by spherical 
spreading alone. As a result, NMFS and the applicant believe that there 
is virtually no possibility of inflicting permanent hearing damage on 
any marine mammals.

Temporary Hearing Loss

    Temporary threshold shift (TTS) is an increase in an individual 
animal's hearing threshold in response to a loud sound (ARPA, 1995). 
Until TTS dissipates (minutes to hours), and original hearing abilities 
return, an animal may not perceive low amplitude sounds that were 
normally within its hearing. This is expected to have only a negligible 
impact on those marine mammals in the immediate area of the experiment, 
as animals are expected to move away from sounds that inflict 
discomfort on them. Because there are no studies of TTS effects in 
marine mammals (Richardson et al. 1995), comparisons with data on 
humans may be useful and relevant. In humans, onset of TTS is 
approximately at 80-100 dB over threshold (ARPA 1995).

Incidental Harassment Takes

    In addition to the zone of hearing loss or temporary impairment 
(mentioned above), Richardson et al. (1991, 1995) have identified three 
zones of influence that may have different effects on marine mammals.
    (1) Zone of audibility (ZOA). The ZOA is the region where a marine 
mammal can be expected to hear a sound. It will fluctuate based upon 
ambient noise level and the hearing threshold of the animal. Using 
spherical and cylindrical spreading models less absorption, the ZOA for 
killer whales, harbor porpoise and harbor seals are predicted to be 
limited to the line-of-sight between the animals and the source(s) for 
the loudest sources and up to 2 km for sources with lower sound 
pressure levels. It should be recognized,

[[Page 13850]]
however, that NMFS does not consider simply hearing noise from an 
activity to mean that the animals are being harassed as marine mammals 
in the coastal environment are continually subject to noise from a 
number of sources, both natural and anthropogenic.
    (2) Zone of responsiveness (ZOR). The ZOR is the region where a 
marine mammal may (or may not) behaviorally respond to a sound source. 
For the sound sources listed in Table 1 of this notice, the predicted 
ZOR is less than 500 m of most sources except source A, which has a ZOR 
approximately 2.5 km for killer whales; source D, which has a ZOR 
approximately 6 km for killer whales and 4 km for harbor porpoise; and 
source E, which has a ZOR approximately 2 km for killer whales (Schmidt 
1996). Because source A is located in five different locations, it will 
have a ZOR that comprises the entire area inside the arrays in addition 
to the 2.5 km outside exterior to each array. Table 6 in the 
application contains the estimated ZOR for each source.
    It should be noted that these ZORs are based upon limited 
information. As a result, the ZORs may be larger or smaller than 
predicted, depending upon the marine mammal species, the level of 
background noise, habituation, and the behavioral state of the animals 
involved.
    (3) Zone of discomfort (ZOD). The ZOD is the region in which sound 
levels are expected to be uncomfortable to marine mammals. It is 
presumed that marine mammals will avoid this zone when the sources are 
operating and those within the ZOD will leave the area, although in 
some cases avoidance may not be possible, especially if geological 
features or water conditions make exiting the area impractical. To 
mitigate this possibility, the applicant has established a monitoring 
plan that is described below.
    Based upon the level found to cause discomfort in humans (Greenlaw 
1987), NMFS and the applicant, propose a contour of 90 dB above 
threshold hearing to define the ZOD. For killer whales and harbor 
porpoise, 90 dB above threshold is approximately 135-140 dB for a wide 
range of frequencies. At least for killer whales, this level is 
supported by observation (Bain 1995).
    For the three species for which audiogram data are available, the 
applicant's model predicts a small ZOD (<=50 m) for all sources except 
for source A, which has a predicted ZOD of 173 m for killer whales, 
source D, with a ZOD of 386 m for killer whales and 220 m for harbor 
porpoise and source E, which has a ZOD of 158 m for killer whales. 
Table 7 in the application contains the estimated ZOD for each source.

Habitat Exclusion

    The area of the experiment is occupied regularly by harbor 
porpoise, Dall's porpoise, killer whales and harbor seals and to a 
significantly lesser extent, by minke whales, elephant seals, Pacific 
white-sided dolphin, northern sea lions, California sea lions, humpback 
whales, and gray whales. While sounds from the experiment may be 
audible to some or all of these species, behavioral effects should not 
be noticeable until the sounds reach some level of discomfort. As a 
result of this discomfort, there is the possibility that the research 
may cause some marine mammals to move out of their preferred habitat.
    (1) Harbor porpoise. While the immediate area of the experiment 
does not appear to be primary habitat for harbor porpoise (Baird and 
Guenther 1994, Raum-Suryan pers. comm. as cited in Schmidt 1996) 
because of similarity to acoustic deterrent devices (Olesiuk et al. 
1995), it is predicted that sources D and E will result in the 
temporary displacement of harbor porpoise, especially on the western 
side of Haro Strait (Schmidt 1996).
    (2) Killer whale. Killer whales forage over a large area of water 
in northern Puget Sound (Schmidt 1996). Therefore, it is highly 
unlikely that exclusion from the relatively small area of the 
experiment would have more than a negligible impact on the stock. 
However, if the sources impeded north-south passage between Haro Strait 
and Boundary Pass, there might be reason for some concern. While this 
is not anticipated, mitigation measures are expected to preclude this 
occurrence.
    (3) Dall's porpoise. While there is evidence that Dall's porpoise 
are less disturbed by boats than harbor porpoise are (Osmek et al. 
1995), other information (McIntyre pers. comm. 1996) indicates that 
Dall's porpoise can be affected by sonar. Alternatively, other research 
results of sound effects on Dall's porpoise (Jones et al. 1986) are 
equivocal. As a result of this lack of evidence, and because of the 
similarity between Dall's porpoise and harbor porpoise, NMFS will 
presume that Dall's porpoise behavior to the experiment's sound sources 
will be similar to that observed for harbor porpoise.
    (4) Harbor seal. The projected ZOR for harbor seal is less than 400 
m and the ZOD is less than 40 m for even the loudest source (source D). 
Because these zones are small, and because the experiment will end 
prior to the main onset of pupping (Suryan 1995), NMFS does not believe 
that this experiment would have more than a negligible impact on harbor 
seals.
    (5) Other marine mammal species. The remaining marine mammal 
species identified in this section are considered uncommon in the area. 
As a result, while this experiment may result in the incidental 
harassment of an individual animal that might enter into the area of 
the experiment, the experiment itself is unlikely to result in more 
than a negligible impact on the species or stock of which the animal is 
a member.

Monitoring

    A monitoring plan has been developed and will be conducted by 
Patrick Miller, Ph.D. candidate, Marine Bioacoustics Lab, Woods Hole 
Oceanographic Institution and the Department of Biology, MIT (DB/MIT). 
In addition, an advisory board for monitoring this activity's impacts 
on marine mammals has been established.
    The goals of the monitoring plan are:
    (1) To document the number of Level B harassment takes by species 
and number. To accomplish this task, a cliffside shore station will be 
established near the sound sources, and area surveys will be conducted 
using a small inflatable craft. Sampling from both the boat and the 
cliff site will be based on the schedule of usage of the sound sources 
to ensure an accurate estimate of the total number of animals present 
and potentially harassed by the sources. This requirement will vary 
depending upon which sound sources are activated, especially sources D 
and E, which are the sources with the largest ZOR. When sources D and E 
are not operating, the size of the ZOR is small (less than 1 km around 
each of the sound sources), and censusing animals in this area can be 
accomplished using a shore station on the western bluff of Spieden 
Island. When sources D and E are operating, the size of the ZOR is much 
larger, with a maximum radius of about 6 km around the D source (DE/MIT 
1996). To accurately estimate the number of animals by species in an 
area of water this size will require the use of both the shore station 
on Spieden Island and a boat to conduct censuses in the area farthest 
away from Spieden Island. The boat will do point censusing according to 
NMFS-approved methodologies in several parts of the ZOR while the 
source is operating.
    Acoustical behavior of killer whales will be studied using the 
vertical arrays, a hydrophone station on Spieden Island, and a towed 
hydrophone array from the killer whale boat. Specifically, DB/MIT will 
document changes in vocalization rates and repertoires when the sources

[[Page 13851]]
are operating from baseline activity in and around the area of the 
experiment. Any observed change in killer whale acoustical activity 
that is directly correlated to a sound produced by the experiment will 
be classified as a ``take'' by harassment.
    (2) To collect data to mitigate potential effects on marine 
mammals, especially habitat exclusion for harbor porpoise and killer 
whales. To obtain a sufficient number of baseline observations needed 
to detect a large change in mean abundance of harbor porpoise within 
the time an animal would be expected to suffer deleterious effects, 
harbor porpoise observations will begin on May 16, 1996, (25 days prior 
to startup of the experiment) using a shore station to measure their 
abundance. To provide a good view of the ZOR on the western side of 
Haro Island, this shore station will be established on the bluff at 
Wymond Pt., Sidney Island.
    For killer whales, in addition to analyzing data collected in 
previous years, DB/MIT will conduct a period of baseline observations 
on killer whale travel behavior in the area. DB/MIT will record the 
likelihood that killer whales pass from north to south given an 
approach to the study area.
    (3) To collect data on the effects of sound on those marine mammals 
present in or near the study area. Data from shore stations and 
censusing vessels will be used to document the abundance and 
distribution of marine mammals in relation to the sound sources over a 
wide range of amplitude exposures. In addition, monitoring will 
determine the size of the ZOR for those species present near the 
sources, compare these measurements to the pre-test calculated ZOR 
size, and determine displacement for harbor porpoise, killer whales and 
harbor seals. For killer whales especially, behavior will be monitored 
by vessel, and data will be collected on swim direction and speed, and 
group spacing and arrangement. Finally, recovery periods for all 
species will be determined through a 3-week post-experiment monitoring 
program.

Mitigation

    Mitigation measures include: (1) Developing and incorporating a 
ramp-up of sound sources A and C over 0.25 sec; (2) incorporating a 
coded sequence mechanism for shutting off source D; (3) hardwiring the 
maximum output of source A down from 185 dB (re 1Pa) to 170 dB 
@ 1 m. and (4) developing a protocol for shutting down sources upon the 
approach of killer whales in order to use the vertical arrays to record 
and analyze their sounds.

National Environmental Policy Act (NEPA)

    NMFS has conducted a review of the potential impacts from the 
issuance of an incidental harassment authorization to DE/MIT and has 
determined that there will be no more than a short-term, negligible 
impact on marine mammals from the issuance of the harassment 
authorization. For that reason, NMFS has determined that issuance of an 
incidental harassment authorization to DE/MIT is categorically excluded 
(as defined in 40 CFR 1508.4) from the preparation of either an 
environmental impact statement or an EA under NEPA and section 
6.02.c.3(i) of NOAA Administrative Order 216-6 for Environmental Review 
Procedures (published August 6, 1991).
    A programmatic EA on issuing incidental harassment authorizations 
under section 101(a)(5)(D) of the MMPA, which was released in 1995, is 
available upon request (see ADDRESSES).

Conclusions

    NMFS believes that most of the acoustic sources proposed for use in 
this experiment are of insufficient amplitude and duty cycle to warrant 
an incidental harassment authorization (literally thousands of similar 
acoustic devices are in use daily in U.S. waters on vessels as fish 
finders, bottom sonars, and as acoustic deterrent devices in commercial 
fisheries); however, because of recent public concern over Scripp's 
Institution of Oceanography's acoustic thermometry of ocean climate, 
oceanographic researchers are correctly taking a cautious approach and 
applying for incidental harassment authorizations to ensure their 
projects go forward.
    NMFS has determined preliminarily that the short-term impact on 
marine mammals from conducting a physical oceanography experiment 
between June 10 and July 5, 1996, using high-frequency sound to study 
the flow field and mixing processes in Haro Strait, Puget Sound, WA, 
may result in a short-term modification in behavior by certain species 
of cetaceans. While behavioral modifications may be made by these 
species of cetaceans to avoid noise, this behavioral change is expected 
to have only a negligible impact on the animals. However, the 
mitigation and monitoring measures that will be part of the 
authorization, if issued, would provide additional protection to ensure 
that the project's impact on marine mammals is at the lowest level 
practicable. NMFS has also determined that this experiment will not 
have an unmitigable adverse impact on the availability of this stock 
for subsistence uses.
    As a result, NMFS proposes to issue an incidental harassment 
authorization for approximately 60 days for the above described 
experiment and post-experiment monitoring, provided the above mentioned 
mitigation and monitoring requirements are incorporated.

Information Solicited

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

    Dated: March 22, 1996.
Patricia A. Montanio,
Deputy Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 96-7624 Filed 3-25-96; 4:31 pm]
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