[Federal Register Volume 82, Number 67 (Monday, April 10, 2017)]
[Notices]
[Pages 17209-17224]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-07031]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
RIN 0648-XE60
Takes of Marine Mammals Incidental to Specified Activities;
Taking Marine Mammals Incidental to the Gustavus Ferry Terminal
Improvements Project
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Notice; issuance of an incidental harassment authorization.
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SUMMARY: In accordance with the regulations implementing the Marine
Mammal Protection Act (MMPA) as amended, notification is hereby given
that we have issued an incidental harassment authorization (IHA) to the
Alaska Department of Transportation and Public Facilities (ADOT&PF) to
incidentally harass seven species of marine mammals during activities
related to the implementation of a Ferry Terminal Improvements Project
in Gustavus, Alaska.
DATES: This authorization is valid from December 15, 2017 through
December 14, 2018.
FOR FURTHER INFORMATION CONTACT: Robert Pauline, Office of Protected
Resources, NMFS, (301) 427-8401.
SUPPLEMENTARY INFORMATION:
Availability
An electronic copy of ADOT&PF's application and supporting
documents, as well as a list of the references cited in this document,
may be obtained online at: www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. In case of problems accessing these documents, please
call the contact listed above (see FOR FURTHER INFORMATION CONTACT).
Background
Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.)
direct the Secretary of Commerce to allow, upon request, the
incidental, but not intentional, taking of small numbers of
[[Page 17210]]
marine mammals by U.S. citizens who engage in a specified activity
(other than commercial fishing) within a specified geographical region
if certain findings are made and either regulations are issued or, if
the taking is limited to harassment, a notice of a proposed
authorization is provided to the public for review.
Authorization for incidental takings shall be granted if NMFS finds
that the taking will have a negligible impact on the species or
stock(s), will not have an unmitigable adverse impact on the
availability of the species or stock(s) for subsistence uses (where
relevant), and if the permissible methods of taking and requirements
pertaining to the mitigation, monitoring and reporting of such takings
are set forth. NMFS has defined ``negligible impact'' in 50 CFR 216.103
as ``an impact resulting from the specified activity that cannot be
reasonably expected to, and is not reasonably likely to, adversely
affect the species or stock through effects on annual rates of
recruitment or survival.''
Section 101(a)(5)(D) of the MMPA established an expedited process
by which citizens of the U.S. can apply for an authorization to
incidentally take small numbers of marine mammals by harassment.
Section 101(a)(5)(D) establishes a 45-day time limit for NMFS' review
of an application followed by a 30-day public notice and comment period
on any proposed authorization for the incidental harassment of marine
mammals. Within 45 days of the close of the comment period, NMFS must
either issue or deny the authorization.
Except with respect to certain activities not pertinent here, the
MMPA defines ``harassment'' as ``any act of pursuit, torment, or
annoyance which (i) has the potential to injure a marine mammal or
marine mammal stock in the wild (Level A harassment); or (ii) has the
potential to disturb a marine mammal or marine mammal stock in the wild
by causing disruption of behavioral patterns, including, but not
limited to, migration, breathing, nursing, breeding, feeding, or
sheltering (Level B harassment).''
Summary of Request
On July 31, 2015, NMFS received an application from the ADOT&PF for
the taking of marine mammals incidental to reconstructing the existing
ferry terminal at Gustavus, Alaska, referred to as the Gustavus Ferry
Terminal. On April 15, 2016, NMFS received a revised application. NMFS
determined that the application was adequate and complete on April 20,
2016. ADOT&PF proposed to conduct in-water work that may incidentally
harass marine mammals (i.e., pile driving and removal). This IHA would
be valid from December 15, 2017 through December 14, 2018.
Proposed activities included as part of the Gustavus Ferry Terminal
Improvements Project with potential to affect marine mammals include
vibratory pile driving and pile removal, as well as impact pile
driving.
Species with the expected potential to be present during the
project timeframe include harbor seal (Phoca vitulina), Steller sea
lion (Eumetopias jubatus), harbor porpoise (Phocoena phocoena), Dall's
porpoise (Phocoenoides dalli), killer whale (Orcinus orca), humpback
whale (Megaptera novaeangliae), and minke whale (Balaenoptera
acutorostrata).
Description of the Specified Activity
Overview
We provided a description of the proposed action in our Federal
Register notice announcing the proposed authorization (81 FR 40852;
June 23, 2016). Please refer to that document; we provide only summary
information here.
The ADOT&PF is modernizing its Gustavus Ferry Terminal in Gustavus,
Alaska. The purpose of the project is to improve the vehicle transfer
span and dock such that damage during heavy storms is prevented, and to
improve the safety of vehicle and pedestrian transfer operations.
ADOT&PF requested an IHA for work that includes removal of the existing
steel bridge float and restraint structure and replacing it with two
steel/concrete bridge lift towers capable of elevating the relocated
steel transfer bridge above the water when not in use. Each tower would
be supported by four 30-inch steel piles.
Dates and Duration
Pile installation and extraction associated with the Gustavus Ferry
Terminal project will begin no sooner than December 15, 2017 and will
be completed no later than December 14, 2018 (one year following IHA
issuance). Project activities are proposed to occur during two time-
periods. The first period will occur in spring of 2018, with pile
driving/removal and in-water work occurring during the period of March
1, 2018 through May 31, 2018. The second period is scheduled for fall
of 2018, with pile driving/removal and in-water work occurring during
the period of September 1, 2018 through November 30, 2018.
Pile driving and removal is estimated to occur for a total of about
171 hours over the course of 16 to 50 days. For the purposes of this
analysis, 50 days of driving will be assumed. Impact pile driving will
take place for up to 57 hours for approximately three hours per day
while vibratory driving will require up to 114 hours and require up to
6 hours per day. Fifty-seven piles will be installed. Sixteen of these
piles will be temporary and will be removed. The pile driving schedule
is shown in Table 1.
Table 1--Pile Driving Schedule
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Project components
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Description Piles
Dock Bridge Lift towers Access float Log float Pile removal installed/ Installation/
extension abutment total piles removal per day
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# of Piles................... 34............ 6............ 8............ 6............ 3............ 16........... 57/73........ 3 piles/day
(maximum).
Pile Size (Diameter)......... 24-inch....... 24-inch...... 30-inch...... 30-inch...... 12.75-inch... 12.75-inch...
Total Strikes (Impact)....... 20,400........ 3,600........ 4,800........ 3,600........ 1,800........ 0............ 34,200....... 1,800 blows/
day.
Total Impact Time............ 34 hrs........ 6 hrs........ 8 hrs........ 6 hrs........ 3 hrs........ 0............ 57 hrs....... 3 hrs/day.
Total Vibratory Time......... 54 hrs........ 9 hrs........ 13 hrs....... 9 hrs........ 5 hrs........ 24 hrs....... 114 hrs...... 6 hrs/day.
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Specific Geographic Region
The proposed activities will occur at the Gustavus Ferry Terminal
located in Gustavus, Alaska on the Icy Passage water body in Southeast
Alaska (See Figures 1 and 2 in the application).
Comments and Responses
A notice of NMFS's proposal to issue an IHA to ADOT&PF was
published in
[[Page 17211]]
the Federal Register on June 23, 2016 (81 FR 40852). That notice
described, in detail, ADOT&PF's activity, the marine mammal species
that may be affected by the activity, and the anticipated effects on
marine mammals. During the 30-day public comment period, NMFS received
only one set of comments, from the Marine Mammal Commission
(Commission); the Commission's recommendations and our responses are
provided here, and the comments have been posted online at:
www.nmfs.noaa.gov/pr/permits/incidental/construction.htm. Please see
the Commission's letter for background and rationale regarding the
recommendations, which are listed below.
Comment 1: The Commission recommended that NMFS use a sound source
level higher than the 154.3 dB re 1 [mu]Pa at 10 m that was recorded at
Kake Harbor by ADOT&PF for deriving disturbance zone isopleths during
vibratory driving of 30-inch steel piles at Gustavus. The Commission
was concerned that this value was considerably lower than other sound
source levels (SSLs) associated with driving piles of similar type and
size.
Response: ADOT&PF implemented sound source verification (SSV)
measurements at Kake Harbor, Alaska and proposed to use this
information as a proxy SSL for the Gustavus Ferry Terminal project. The
results determined a SSL of 154.3 dB re 1 [mu]Pa at 10 m. This value
was further modified to 157.7 dB re 1 [mu]Pa after the original
findings were re-analyzed to include additional data from a single
restraint pile that had not been included in the initial results. NMFS
agrees that this SSL is lower than others that have been documented in
datasets generated from locations outside Alaska. However, ADOT&PF will
be using the same types of vibratory and impact hammers at Gustavus as
were used at Kake. Additionally, while the substrate at Gustavus is not
identical to those at Kake, both are similarly composed of relatively
fine-grained sediments. The project at Kake was also using pile types
and sizes that are comparable to those planned for use at Gustavus.
Finally, NMFS will require ADOT&PF to conduct SSV testing as a
monitoring requirement. If the recorded SSLs at Gustavus are greater
than those measured at Kake, ADOT&PF will increase the isopleths as
appropriate.
Comment 2: The Commission recommended that NMFS ensure that the
estimated numbers of takes are adequate if the amended Level B
harassment zone calculated from a source greater than 157.7 dB re 1
[mu]Pa extends into Icy Strait.
Response: NMFS used a SSL of 157.7 dB re 1 [mu]Pa to calculate the
Level B harassment isopleth, which does not extend into Icy Strait. If
the Level B harassment zone needs to be increased after ADOT&PF
conducts on-site SSV verification testing, NMFS will re-evaluate
numbers of estimated takes as appropriate.
Comment 3: The Commission recommended that NMFS compile available
in-situ pile driving and removal data into a central database. This
would enable analysts to crosscheck data in situations like the one
discussed herein, as well as in situations when applicants are having
difficulty determining proxy source levels.
Response: NMFS agrees with the Commission that a database would be
of value and has begun compiling underwater sound-related information.
Comment 4: The Commission recommends that NMFS require every
applicant to specify the sediment composition, water depth (in terms of
hydrophone placement and bathymetry), duration over which the pressure
was averaged for sound pressure level root mean square (SPLrms)
metrics, and median values in all future hydroacoustic monitoring
reports.
Response: NMFS will require every applicant to specify the sediment
composition and water depth (in terms of hydrophone placement and
bathymetry) for SSV. In addition, NMFS will require the applicants to
provide median and averaged values of sound source measurements.
However, duration over which the pressure was averaged for SPLrms
values can vary for impact pile driving since NMFS requires that SPLrms
be computed using a 90 percent energy window. Therefore, NMFS will only
require the applicant to provide the duration from vibratory pile
driving measurements.
Comment 5: The Commission recommended that NMFS ensure consistency
regarding integration of timeframes used for SPLrms measurements (e.g.,
1-second averages, maximum over 10 seconds, or maximum over 30 seconds)
in all future hydroacoustic monitoring reports.
Response: In 2012, NMFS worked with scientists from the University
of Washington and stakeholders from the Washington State Department of
Transportation to develop a set of guidance for data collection methods
to characterize impact and vibratory pile driving source levels
relevant to marine mammals. For vibratory pile driving, the guidance
recommends taking 10 second averages across the whole event and
averaging all the 10 second periods to calculate the SPLrms value. For
impact pile driving, the guidance recommends characterizing overall
dBrms levels by integrating sound for each waveform across 90% of the
acoustic energy in each wave (using the 5-95 percentiles to establish
the 90% criterion) and averaging across all waves in the pile-driving
event. NMFS will require these methods for vibratory and impact pile
driving sound source measurements in the future.
Description of Marine Mammals in the Area of the Specified Activity
There are seven marine mammal species known to occur in the
vicinity of the project area. Two of the species are known to occur
near the Gustavus Ferry terminal; the harbor seal and Steller sea lion.
The remaining five species may occur in Icy Passage but less frequently
and farther from the ferry terminal: Harbor porpoise, Dall's porpoise,
killer whale, humpback whale, and minke whale.
We reviewed ADOT&PF's detailed species descriptions, including life
history information, for accuracy and completeness and refer the reader
to Section 3 of ADOT&PF's application as well as our notice of proposed
IHA published in the Federal Register (81 FR 40852; June 23, 2016).
Please also refer to NMFS' Web site (www.nmfs.noaa.gov/pr/species/mammals) for generalized species accounts that provide information
regarding the biology and behavior of the marine resources that occur
in proximity to the project area.
Table 2 lists marine mammal stocks that could occur near the
project area that may be subject to harassment and summarizes key
information regarding stock status and abundance. Note that the listed
status of the humpback whale was updated in 2016 after NMFS conducted a
global status review (81 FR 62259; September 8, 2016). The humpback
whale was listed as endangered under the Endangered Species
Conservation Act (ESCA) on December 2, 1970 (35 FR 18319). Congress
replaced the ESCA with the Endangered Species Act (ESA) in 1973, and
humpback whales continued to be listed as endangered. Under the revised
listing status, NMFS identified 14 distinct population segments (DPS).
Of these 14 DPSs, four remain listed as endangered, one is listed as
threatened, and the remaining nine were identified as not warranted for
listing. For humpback whales found in southeast Alaska, NMFS
anticipates that the vast
[[Page 17212]]
majority (approximately 94 percent) would be from the non-listed Hawaii
DPS. A small proportion (approximately 6 percent) of whales occurring
in southeast Alaska are expected to be of the Mexico DPS, which remains
listed as threatened.
Please see NMFS' Stock Assessment Reports (SAR), available at
www.nmfs.noaa.gov/pr/sars, for more detailed accounts of these stocks'
status and abundance.
Table 2--Marine Mammal Species Potentially Present in Region of Activity
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Stock abundance Frequency of occurrence
Common name Scientific name estimate \1\ ESA status MMPA status \2\
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Harbor seal....................... Phoca vitulina....... 7,210 (Glacier Bay/ Not listed........... Not Strategic, non- Likely.
Icy Strait). depleted.
Steller sea lion.................. Eumetopias jubatus... 50,983 (western Endangered (western Strategic, depleted Likely.
distinct population Distinct Population (western DPS)/Not
segment in Alaska)/ Segment). Strategic, non-
71,562 (eastern depleted (eastern
stock). DPS).
Dall's porpoise................... Phocoenoides dalli... 83,400............... Not listed........... Not Strategic, non- Infrequent.
depleted.
Harbor porpoise................... Phocoena phocoena.... 11,146 (Southeast Not listed........... Strategic, non- Likely.
Alaska). depleted.
Humpback whale (Central North Megaptera 10,103............... Threatened (Mexico Strategic, depleted Infrequent.
Pacific Stock). novaeangliae. DPS)/Not listed (Mexico DPS)/Not
(Hawaii DPS). Strategic, non-
depleted (Hawaii
DPS).
Killer whale...................... Orcinus orca......... 261 (Northern Not listed........... Not strategic, non- Infrequent.
resident)/587 (Gulf depleted (all
of Alaska transient)/ stocks).
243 (West coast
transient).
Minke whale....................... Balaenoptera Unknown.............. Not listed........... Not Strategic/non- Infrequent.
acutorostrata. depleted.
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\1\ NMFS marine mammal stock assessment reports at: http://www.nmfs.noaa.gov/pr/sars/species.htm.
\2\ Infrequent: Confirmed, but irregular sightings. Likely: Confirmed and regular sightings of the species in the area year-round.
Potential Effects of the Specified Activity on Marine Mammals
The effects of underwater noise from pile driving activities for
the Ferry Terminal Improvements Project have the potential to result in
harassment of marine mammals in the vicinity of the action area. The
Federal Register notice for the proposed IHA (81 FR 40852, June 23,
2016) included a discussion of the effects of anthropogenic noise on
marine mammals. Therefore, that information is not repeated here;
please refer to the Federal Register notice for that information. No
instances of serious injury or mortality are expected as a result of
the pile driving activities.
Anticipated Effects on Habitat
The main impact associated with the ADOT&PF project would be
temporarily elevated sound levels and the associated direct effects on
marine mammals. The project would not result in permanent impacts to
habitats used directly by marine mammals but may have potential short-
term impacts to food sources such as forage fish, and minor impacts to
the immediate substrate resulting in a temporary, localized increase in
turbidity. These potential effects are discussed in detail in the
Federal Register notice for the proposed IHA (81 FR 40852, June 23,
2016), therefore that information is not repeated here; please refer to
that Federal Register notice for that information.
Mitigation
In order to issue an IHA under section 101(a)(5)(D) of the MMPA,
NMFS must set forth the permissible methods of taking pursuant to such
activity, ``and other means of effecting the least practicable impact
on such species or stock and its habitat, paying particular attention
to rookeries, mating grounds, and areas of similar significance, and on
the availability of such species or stock for taking'' for certain
subsistence uses. NMFS regulations require applicants for incidental
take authorizations to include information about the availability and
feasibility (economic and technological) of equipment, methods, and
manner of conducting such activity or other means of effecting the
least practicable adverse impact upon the affected species or stocks,
their habitat (50 CFR 216.104(a)(11)). For the proposed project,
ADOT&PF worked with NMFS to develop the following mitigation measures
to minimize the potential impacts to marine mammals in the project
vicinity. The primary purposes of these mitigation measures are to
minimize sound levels from the activities, and to shut down operations
and monitor marine mammals within designated zones of influence
corresponding to NMFS' current Level A and B harassment thresholds.
In addition to the measures described later in this section,
ADOT&PF will employ the following standard mitigation measures:
(a) Conduct briefings between construction supervisors and crews,
and marine mammal monitoring team, prior to the start of all pile
driving activity, and when new personnel join the work, in order to
explain responsibilities, communication procedures, marine mammal
monitoring protocol, and operational procedures;
(b) For in-water heavy machinery work other than pile driving
(e.g., standard barges, tug boats, barge-mounted excavators, or
clamshell equipment used to place or remove material), if a marine
mammal comes within 10 m, operations shall cease and vessels shall
reduce speed to the minimum level required to maintain steerage and
safe working conditions. This type of work could include the following
activities: (1) Movement of the barge to the pile location; or (2)
positioning of the pile on the substrate via a crane (i.e., stabbing
the pile); and
(c) To limit the amount of waterborne noise, a vibratory hammer
will be used for initial driving, followed by an impact hammer to proof
the pile to required load-bearing capacity.
Establishment of Shutdown Zone--For all pile driving activities,
ADOT&PF will establish a shutdown zone. The purpose of a shutdown zone
is generally to define an area within which shutdown of activity would
occur upon sighting of a marine mammal (or in anticipation of an animal
entering the defined area). In this case, shutdown zones are intended
to contain areas in which SPLs equal or exceed acoustic injury
criteria, based on NMFS' new acoustic technical guidance published in
the Federal Register on August 4, 2016 (81 FR 51693). The shutdown
zones vary for specific species. For impact driving, the shutdown zone
extends to 550 m for humpback whale and minke whale; for harbor seal,
harbor porpoise and Dall's porpoise, the zone
[[Page 17213]]
extends to 100 m; and for killer whale and Steller sea lion, the zone
is set at 25 m. Note that for harbor seal, harbor porpoise, and Dall's
porpoise, the injury zones extend beyond the designated shutdown zones,
resulting in potential for some Level A take for these species. This
approach will allow operations to continue when animals from these
three species are sighted beyond the the 100 m shutdown zone. If the
shutdown zone extended out to the full PTS isopleth (282.3 m for harbor
seal; 628 m for harbor porpoise and Dall's porpoise) for these species,
it is likely that impact driving operations would have to be shut down
continuously due to the relatively high abundance of animals in the
project area. Permitting Level A take will allow the project to be
completed in a relatively expedient manner while impacting a limited
number of animals. For vibratory driving, the shutdown zone is 20 m for
harbor porpoise, Dall's porpoise, humpback whale and minke whale. The
shutdown zone for killer whale, harbor seal and Steller sea lion is 10
m during vibratory driving. The derivation of these shutdown isopleths
is described in the Estimated Take section.
Establishment of Level A Take Zone--ADOT&PF will establish Level A
take zones which are areas beyond the shutdown zones where animals may
be exposed to sound levels that could result in permanent threshold
shift (PTS).
Establishment of Disturbance Zones--ADOT&PF will establish Level B
disturbance zones or zones of influence (ZOI) which, according to
current NMFS guidance, are areas where SPLs equal or exceed 160 dB rms
for impact driving and 120 dB rms for vibratory driving. Disturbance
zones provide utility for monitoring by establishing monitoring
protocols for areas adjacent to the shutdown zones. Monitoring of
disturbance zones enables observers to be aware of and communicate the
presence of marine mammals in the project area but outside the shutdown
zone and thus prepare for potential shutdowns of activity.
Temporal and Seasonal Restrictions--The following restrictions will
apply to all pile driving activities:
(a) Work may only occur during daylight hours, when visual
monitoring of marine mammals can be conducted;
(b) All in-water construction will be limited to the periods
between March 1 and May 31, 2018, and September 1 and November 30,
2018; and
(c) Starting March 1, 2018 through May 31, 2018 and September 1,
2018, through September 30, 2018, all pile driving operations will end
at 4 p.m. as charter fishing vessels return to the dock. Steller sea
lions are attracted and habituated to the project area to forage on
scraps from the charter boats that are returning to the dock and
cleaning fish in the late afternoon (pers. Comm. Chris Gabriele (Hart
Crowser 2015)). Late afternoon is likely to be the period of the day
when the highest numbers of sea lions are present in the action area,
so stopping operations will limit exposure to concentrated higher
numbers of Steller sea lions. Because different numbers of fishing
charter vessels may be operating each day and returning at various
times, pile driving will stop if 5 or more Steller sea lions are
observed following charter fishing vessels to the dock prior to 4 p.m.
Soft Start--The use of a soft-start procedure is believed to
provide additional protection to marine mammals by providing warning
and/or giving marine mammals a chance to leave the area prior to the
hammer operating at full capacity. For impact pile driving, contractors
will be required to provide an initial set of strikes from the hammer
at 40 percent energy, each strike followed by no less than a 30-second
waiting period. This procedure will be conducted a total of three times
before impact pile driving begins. Soft start will also be conducted
whenever impact driving commences after 30 or more minutes since the
last impact pile driving action.
Sound Attenuation Devices--During impact pile driving, contractors
will be required to use pile caps. Pile caps reduce the sound generated
by the pile, although the level of reduction can vary.
Mitigation Conclusions
We have carefully evaluated ADOT&PF's mitigation measures and
considered their effectiveness in past implementation to determine
whether they are likely to effect the least practicable impact on the
affected marine mammal species and stocks and their habitat. Our
evaluation of potential measures included consideration of the
following factors in relation to one another: (1) The manner in which,
and the degree to which, the successful implementation of the measure
is expected to minimize adverse impacts to marine mammals, (2) the
proven or likely efficacy of the specific measure to minimize adverse
impacts as planned; and (3) the practicability of the measure for
applicant implementation.
Any mitigation measure(s) we prescribe should be able to
accomplish, have a reasonable likelihood of accomplishing (based on
current science), or contribute to the accomplishment of one or more of
the general goals listed below:
(1) Avoidance or minimization of injury or death of marine mammals
wherever possible (goals 2, 3, and 4 may contribute to this goal);
(2) A reduction in the number (total number or number at
biologically important time or location) of individual marine mammals
exposed to stimuli expected to result in incidental take (this goal may
contribute to 1 above);
(3) A reduction in the number (total number or number at
biologically important time or location) of times any individual marine
mammal would be exposed to stimuli expected to result in incidental
take (this goal may contribute to 1 above);
(4) A reduction in the intensity of exposure to stimuli expected to
result in incidental take (this goal may contribute to 1 above);
(5) Avoidance or minimization of adverse effects to marine mammal
habitat, paying particular attention to the prey base, blockage or
limitation of passage to or from biologically important areas,
permanent destruction of habitat, or temporary disturbance of habitat
during a biologically important time; and
(6) For monitoring directly related to mitigation, an increase in
the probability of detecting marine mammals, thus allowing for more
effective implementation of the mitigation.
Based on our evaluation of ADOT&PF's measures, including
information from monitoring of implementation of mitigation measures
very similar to those described here under previous IHAs from other
marine construction projects, we have determined that the mitigation
measures provide the means of effecting the least practicable impact on
marine mammal species or stocks and their habitat, paying particular
attention to rookeries, mating grounds, and areas of similar
significance.
Monitoring and Reporting
In order to issue an IHA for an activity, section 101(a)(5)(D) of
the MMPA states that NMFS must set forth ``requirements pertaining to
the monitoring and reporting of such taking.'' The MMPA implementing
regulations at 50 CFR 216.104(a)(13) indicate that requests for
incidental take authorizations must include the suggested means of
accomplishing the necessary monitoring and reporting that will result
in increased knowledge of the species and of the level of taking or
impacts on populations of marine
[[Page 17214]]
mammals that are expected to be present in the action area. ADOT&PF
submitted a marine mammal monitoring plan as part of the IHA
application. It can be found in Appendix B of the Application.
Any monitoring requirement we prescribe should improve our
understanding of one or more of the following:
Occurrence of marine mammal species in action area (e.g.,
presence, abundance, distribution, density);
Nature, scope, or context of likely marine mammal exposure
to potential stressors/impacts (individual or cumulative, acute or
chronic), through better understanding of: (1) Action or environment
(e.g., source characterization, propagation, ambient noise); (2)
Affected species (e.g., life history, dive patterns); (3) Co-occurrence
of marine mammal species with the action; or (4) Biological or
behavioral context of exposure (e.g., age, calving or feeding areas);
Individual responses to acute stressors, or impacts of
chronic exposures (behavioral or physiological);
How anticipated responses to stressors impact either: (1)
Long-term fitness and survival of an individual; or (2) Population,
species, or stock; and
Effects on marine mammal habitat and resultant impacts to
marine mammals.
Mitigation and monitoring effectiveness.
Monitoring Measures
The monitoring measures described below for the Final IHA have been
updated somewhat from those listed in the notice of proposed
authorization, to reflect NMFS' current standard monitoring measures
for applicable IHAs. These updates do not change the substance, scope,
or anticipated effectiveness of the monitoring measures.
Monitoring Protocols--Monitoring will be conducted by qualified
marine mammal observers (MMOs), who are trained biologists, with the
following minimum qualifications:
Independent observers (i.e., not construction personnel)
are required;
At least one observer must have prior experience working
as an observer;
Other observers may substitute education (undergraduate
degree in biological science or related field) or training for
experience;
Ability to conduct field observations and collect data
according to assigned protocols.
Experience or training in the field identification of
marine mammals, including the identification of behaviors;
Sufficient training, orientation, or experience with the
construction operation to provide for personal safety during
observations;
Writing skills sufficient to prepare a report of
observations including but not limited to the number and species of
marine mammals observed; dates and times when in-water construction
activities were conducted; dates and times when in-water construction
activities were suspended to avoid potential incidental injury from
construction sound of marine mammals observed within a defined shutdown
zone; and marine mammal behavior;
Ability to communicate orally, by radio or in person, with
project personnel to provide real-time information on marine mammals
observed in the area as necessary; and
NMFS will require submission and approval of observer CVs.
In order to effectively monitor the pile driving monitoring zones,
the MMOs will be positioned at the best practical vantage points. The
monitoring position may vary based on pile driving activities and the
locations of the piles and driving equipment. These may include the
catwalk at the ferry terminal, the contractor barge, on a vessel, or
another location deemed to be more advantageous. The monitoring
location will be identified with the following characteristics: (1)
Unobstructed view of pile being driven; (2) Unobstructed view of all
water within a 3,265 m (vibratory driving) and 2,090 m (impact driving)
radius of each pile, although it is understood that monitoring may be
impaired at longer distances; (3) Clear view of pile driving operator
or construction foreman in the event of radio failure; and; (4) Safe
distance from pile driving activities in the construction area.
A total of two observers will be on site and actively observing the
shutdown and disturbance zones during all pile driving and extraction
activities. Observers will use their naked eye with the aid of big-eye
binoculars and a spotting scope to search continuously for marine
mammals during all pile driving and extraction activities. One observer
will always be positioned on the dock looking out to monitor the zone
that is currently in effect. A second observer will be located on
either the dock supplementing efforts of the first observer in
monitoring from that point, or, when weather and safety conditions
permit, on a vessel transiting the observation zones. In the Federal
Register notice for the proposed IHA, NMFS had recommended that ADOT&PF
coordinate with the NPS and whale-watching charters to augment their
land-based monitoring with information from boats in Icy Strait/
Passage. However, most NPS surveys and whale-watching charters occur
outside of the designated work windows for this project (i.e.,
September through November and March through May). Therefore, this
protocol has been removed as a monitoring requirement under this IHA.
However, monitoring will be augmented through the use of two on-site
observers, rather than the one on-site observer required under the
proposed IHA.
The following additional measures apply to visual monitoring:
Monitoring will begin 30 minutes prior to pile driving.
This will ensure that all marine mammals in the monitoring zone are
documented and that no marine mammals are present in the injury zone;
If a marine mammal comes within or approaches the shutdown
zone, pile driving operations shall cease. Pile driving will only
commence once observers have declared the shutdown zone clear of the
marine mammals or if it has not been seen in the shutdown zone for 30
minutes for cetaceans or 15 minutes for pinnipeds. Their behavior will
be monitored and documented. The shutdown zone may only be declared
clear, and pile driving started, when the entire shutdown zone is
visible (i.e., when not obscured by dark, rain, fog, etc.);
When a marine mammal is observed, its location will be
determined using a rangefinder to verify distance and a GPS or compass
to verify heading;
The MMOs will record any cetacean or pinniped present in
the injury zone. The Level A zone extends out to 630 m from the site of
impact pile driving activity for harbor porpoise and Dall's porpoise.
The Level A zone for harbor seals during impact driving is set at 285
m. There are no Level A take zones applicable to other species for
which take is authorized.
The MMOs will record any cetacean or pinniped present in
the disturbance zone. For impact driving the Level B harassment area
encompasses a radius of 2,090 m from the site of pile driving. During
vibratory driving radius of the Level B harassment area extends to
3,265 m.
At the end of the pile driving day, post-construction
monitoring will be conducted for 30 minutes beyond the cessation of
pile driving;
If any marine mammal species are encountered during
activities that are not listed in Table 1 for authorized
[[Page 17215]]
taking and are likely to be exposed to SPLs greater than or equal to
160 dB re 1 [mu]Pa (rms) for impact driving and 120 dB re 1 [mu]Pa
(rms) for vibratory driving, then the ADOT&PF must stop pile driving
activities and report observations to NMFS' Office of Protected
Resources;
If waters exceed a sea-state which restricts the
observers' ability to make observations within the marine mammal
shutdown zone (e.g., excessive wind or fog), pile installation and
removal will cease. Pile driving will not be initiated until the entire
shutdown zone is visible.
Data Collection
Observers are required to use approved data forms. Among other
pieces of information, ADOT&PF will record detailed information about
any implementation of shutdowns, including the distance of animals to
the pile and description of specific actions that ensued and resulting
behavior of the animal, if any. In addition, the ADOT&PF will attempt
to distinguish between the number of individual animals taken and the
number of incidents of take. At a minimum, the following information
will be collected on the sighting forms:
Date and time that monitored activity begins or ends;
Construction activities occurring during each observation
period;
Detailed information about any implementation of
shutdowns, including the distance of animals to the pile and
description of specific actions that ensued and resulting behavior of
the animal, if any;
Weather parameters (e.g., percent cover, visibility);
Water conditions (e.g., sea state, tide state);
Species, numbers, and, if possible, sex and age class of
marine mammals;
Description of any observable marine mammal behavior
patterns, including bearing and direction of travel and distance from
pile driving activity;
Distance from pile driving activities to marine mammals
and distance from the marine mammals to the observation point;
Locations of all marine mammal observations; and
Other human activity in the area.
Sound Source Verification
SSV testing of impact and vibratory pile driving will be conducted
for this project within seven days of initiating underwater pile
driving work. The monitoring plan will be in agreement with a NMFS
document titled ``Guidance Document: Data Collection Methods to
Characterize Impact and Vibratory Pile Driving Source Levels Relevant
to Marine Mammals'' dated January 31, 2012. The SSV will be conducted
by an acoustical firm with prior experience conducting SSV tests in
Alaska. NMFS must approve the acoustic monitoring plan. Results will be
sent to NMFS no later than 14 days after field-testing has been
completed. If necessary, the shutdown, Level A, and Level B harassment
zones will be adjusted to meet MMPA requirements within 7 days of NMFS
receiving field results.
Reporting
ADOT&PF will notify NMFS prior to the initiation of the pile
driving activities and will provide NMFS with a draft monitoring report
within 90 days of the conclusion of the construction work. This report
will detail the monitoring protocol, summarize the data recorded during
monitoring, and estimate the number of marine mammals that may have
been harassed. If no comments are received from NMFS within 30 days of
submission of the draft final report, the draft final report will
constitute the final report. If comments are received, a final report
must be submitted within 30 days after receipt of comments.
Estimated Take
This section includes an estimate of the number of incidental
``takes'' proposed for authorization pursuant to this IHA, which will
inform both NMFS' consideration of whether the number of takes is
``small'' and the negligible impact determination.
Except with respect to certain activities not pertinent here,
section 3(18) of the MMPA defines ``harassment'' as: ``. . . any act of
pursuit, torment, or annoyance which (i) has the potential to injure a
marine mammal or marine mammal stock in the wild (Level A harassment);
or (ii) has the potential to disturb a marine mammal or marine mammal
stock in the wild by causing disruption of behavioral patterns,
including, but not limited to, migration, breathing, nursing, breeding,
feeding, or sheltering (Level B harassment).''
No serious injury or mortality is anticipated to result from this
activity. Limited take of three species of marine mammal (i.e., harbor
seal, harbor porpoise, and Dall's porpoise) by Level A harassment
(injury) is authorized due to potential auditory injury that cannot
reasonably be prevented through mitigation. Mitigation zones are
expected to reduce Level A harassment for these three species and
prevent Level A harassment for all other species. Level B harassment
(behavioral disturbance) is expected to occur and take is authorized
for the numbers identified below.
Given the many uncertainties in predicting the quantity and types
of impacts of sound on marine mammals, it is common practice to
estimate how many animals are likely to be present within a particular
distance of a given activity, or exposed to a particular level of
sound.
ADOT&PF has requested authorization for the incidental taking of
small numbers of marine mammals near the Gustavus Ferry Terminal that
may result from impact pile driving, vibratory pile driving and
vibratory pile removal. In order to estimate the potential incidents of
take that may occur incidental to the specified activity, we must first
estimate the extent of the sound field that may be produced by the
activity and then consider in combination with information about marine
mammal density or abundance in the project area. We first provide
information on applicable sound thresholds for determining effects to
marine mammals before describing the information used in estimating the
sound fields, the available marine mammal density or abundance
information, and the method of estimating potential incidences of take.
Sound Thresholds
We use sound exposure thresholds to determine when an activity that
produces sound might result in impacts to a marine mammal such that a
take by injury or behavioral harassment might occur. These thresholds
are used to estimate when injury or harassment may occur.
Distance to Sound Thresholds
The sound field in the project area is the existing ambient noise
plus additional construction noise from the project. The primary
components of the project expected to affect marine mammals are the
sounds generated by impact pile driving, vibratory pile driving, and
vibratory pile removal.
In order to calculate distances to the Level A and Level B sound
thresholds, NMFS used acoustic monitoring data that had been collected
at the Kake Ferry Terminal by ADOT&PF. ADOT&PF implemented SSV
measurements at Kake Harbor, Alaska and used this information as a
proxy SSL for the Gustavus Ferry Terminal project. The results
determined a SSL of 157.7 dB re 1 [mu]Pa rms at 10 m for vibratory
driving, 194.8 dB re 1 [mu]Pa rms
[[Page 17216]]
at 10 m for impact driving, and single strike/shot sound exposure level
(SEL) of 179.3 dB. These SSLs are different than those found in the
notice of proposed authorization. The Kake Harbor findings were re-
analyzed to include additional data from a single restraint pile that
had not been included in the original notice, resulting in elevated
SSLs and larger Level A and Level B isopleths associated with the
planned impact and vibratory driving.
The formula below is used to calculate underwater sound
propagation. Transmission loss (TL) is the decrease in acoustic
intensity as an acoustic pressure wave propagates out from a source. TL
parameters vary with frequency, temperature, sea conditions, current,
source and receiver depth, water depth, water chemistry, and bottom
composition and topography. The general formula for underwater TL is:
TL = B * log10 (R1/R2)
Where:
TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R1 = the distance of the modeled SPL from the driven
pile, and
R2 = the distance from the driven pile of the initial
measurement.
NMFS typically recommends a default practical spreading loss of 15 dB
per tenfold increase in distance. ADOT&PF analyzed the available
underwater acoustic data utilizing the practical spreading loss model.
On August 4, 2016, NMFS released its Technical Guidance for
Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing
(Guidance, available at http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm). This new guidance established new thresholds for
predicting auditory injury, which equates to Level A harassment under
the MMPA. In the Federal Register notice (81 FR 51694), NMFS explained
the approach it would take during a transition period, wherein we
balance the need to consider this new best available science with the
fact that some applicants have already committed time and resources to
the development of analyses based on our previous guidance and have
constraints that preclude the recalculation of take estimates, as well
as where the action is in the agency's decision-making pipeline. In
that Notice, we included a non-exhaustive list of factors that would
inform the most appropriate approach for considering the new Guidance,
including: The scope of effects; how far in the process the applicant
has progressed; when the authorization is needed; the cost and
complexity of the analysis; and the degree to which the guidance is
expected to affect our analysis. In this case, ADOT&PF initially
submitted a request for authorization on June 30, 2015. A revised
application was submitted on April 15, 2016. A Federal Register notice
announcing the proposed authorization was published on June 23, 2016
(81 FR 40852). Under the new Guidance, NMFS determined that there is a
greater likelihood of auditory injury for low-frequency cetaceans
(i.e., humpback whale, minke whale); high-frequency cetaceans (i.e.,
harbor porpoise, Dall's porpoise); and Phocid pinnipeds (i.e., harbor
seals) during impact driving than was considered in our notice of
proposed authorization (81 FR 40852). In order to address this
likelihood, we increased the required shutdown zones for humpback and
minke whales, harbor porpoise, Dall's porpoise, and harbor seals. In
addition, to account for the potential that harbor seals, harbor
porpoises and Dall's porpoises may enter into the Level A take zones
that exists beyond the designated shutdown zone, we authorize the
taking by Level A harassment of limited numbers of these species. In
summary, we have considered the new Guidance and believe that the
likelihood of injury is adequately addressed in the analysis contained
herein and appropriate protective measures are in place in the IHA.
The calculation of the Level A harassment zones utilized the
methods presented in Appendix D of the Guidance, and the accompanying
User Spreadsheet. The Guidance provides updated PTS onset thresholds
using the cumulative SEL (SELcum) metric, which incorporates
marine mammal auditory weighting functions, to identify the received
levels, or acoustic thresholds, at which individual marine mammals are
predicted to experience changes in their hearing sensitivity for acute,
incidental exposure to all underwater anthropogenic sound sources. The
Guidance (Appendix D) and its companion User Spreadsheet provide
alternative methodology for incorporating these more complex thresholds
and associated weighting functions.
The User Spreadsheet accounts for effective hearing ranges using
Weighting Factor Adjustments (WFAs), and ADOT&PF's application uses the
recommended values for vibratory and impact driving therein. NMFS' new
acoustic thresholds use dual metrics of SELcum and peak
sound level (PK) for impulsive sounds (e.g., impact pile driving) and
SELcum for non-impulsive sounds (e.g., vibratory pile
driving) (Table 3). ADOT&PF used source level measurements from similar
pile driving events and, using the User Spreadsheet, applied the
updated PTS onset thresholds for impulsive PK and SELcum
assuming 600 strikes per pile and installation of 3 piles per day to
determine distance to the isopleths for PTS onset for impact pile
driving. For vibratory pile driving, ADOT&PF used the User Spreadsheet
to determine isopleth estimates for PTS onset using the cumulative
sound exposure level metric (LE) assuming a driving time of
up to 6 hours per day. In determining the cumulative sound exposure
levels, the Guidance considers the duration of the activity, the sound
exposure level produced by the source during one working day, and the
effective hearing range of the receiving species. In the case of the
duel metric acoustic thresholds (Lpk and LE) for
impulsive sound, the larger of the two isopleths for calculating PTS
onset is used. These values were then used to develop mitigation
measures for proposed pile driving activities (Table 3).
NMFS's new acoustic guidance established new thresholds for
predicting auditory injury (Level A Harassment). The Guidance indicates
that there is a greater likelihood of auditory injury for low-frequency
cetaceans, high-frequency cetaceans, and Phocid pinnipeds than was
considered in our notice of proposed authorization. The practical
spreading loss model estimates injury zones for functional hearing
groups for which take is authorized for pulsed sound generated during
impact pile driving (Table 4) and non-pulsed sound during vibratory
pile driving (Table 5).
[[Page 17217]]
Table 3--Summary of PTS Onset Acoustic Thresholds
------------------------------------------------------------------------
PTS onset acoustic thresholds *
(received level)
Hearing group -----------------------------------------
Impulsive Non-impulsive
------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans.. Lpk,flat: 219 dB, LE,LF,24h: 199
LE,LF,24h: 183 dB. dB.
Mid-Frequency (MF) Cetaceans.. Lpk,flat: 230 dB, LE,MF,24h: 198
LE,MF,24h: 185 dB. dB.
High-Frequency (HF) Cetaceans. Lpk,flat: 202 dB, LE,HF,24h: 173
LE,HF,24h: 155 dB. dB.
Phocid Pinnipeds (PW) Lpk,flat: 218 dB, LE,PW,24h: 201
(Underwater). LE,PW,24h: 185 dB. dB.
Otariid Pinnipeds (OW) Lpk,flat: 232 dB, LE,OW,24h: 219
(Underwater). LE,OW,24h: 203 dB. dB.
------------------------------------------------------------------------
* Dual metric acoustic thresholds for impulsive sounds: Use whichever
results in the largest isopleth for calculating PTS onset. If a non-
impulsive sound has the potential of exceeding the peak sound pressure
level thresholds associated with impulsive sounds, these thresholds
should also be considered.
Note: Peak sound pressure (Lpk) has a reference value of 1 [micro]Pa,
and cumulative sound exposure level (LE) has a reference value of
1[micro]Pa\2\s. In this Table, thresholds are abbreviated to reflect
American National Standards Institute standards (ANSI 2013). However,
peak sound pressure is defined by ANSI as incorporating frequency
weighting, which is not the intent for this Technical Guidance. Hence,
the subscript ``flat'' is being included to indicate peak sound
pressure should be flat weighted or unweighted within the generalized
hearing range. The subscript associated with cumulative sound exposure
level thresholds indicates the designated marine mammal auditory
weighting function (LF, MF, and HF cetaceans, and PW and OW pinnipeds)
and that the recommended accumulation period is 24 hours. The
cumulative sound exposure level thresholds could be exceeded in a
multitude of ways (i.e., varying exposure levels and durations, duty
cycle). When possible, it is valuable for action proponents to
indicate the conditions under which these acoustic thresholds will be
exceeded.
Table 4--Underwater Level A Injury Threshold Decibel Levels and Corresponding Isopleths for Functional Hearing Groups During Impact Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
High-frequency
Low-frequency Mid-frequency cetaceans Phocid Otariid
Hearing group cetaceans cetaceans (harbor pinnipeds pinnipeds
(humpback whale, (killer whale) porpoise, (harbor seal) (Steller sea
minke whale) Dall's porpoise) lion)
--------------------------------------------------------------------------------------------------------------------------------------------------------
SELcum Threshold.............................................. 183 185 155 185 203
PTS Isopleth to threshold (m)/Impact Driving.................. 527.5 18.8 628.3 282.3 20.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
*All decibel levels referenced to 1 [mu]Pa. Note all thresholds are based off root mean square (rms) levels
** PTS = Permanent Threshold Shift.
Based on this data NMFS will require shutdown zones that extend to
550 m for humpback whale and minke whale; 100 m for harbor seal, harbor
porpoise and Dall's porpoise; and 25 m for killer whale and Steller sea
lion. NMFS will also require Level A take zones which are areas beyond
the shutdown zones where animals may be exposed to sound levels that
could result in permanent threshold shift (PTS). The Level A zone of
628.3 m will be rounded to a zone of 630 m for harbor porpoise and
Dall's porpoise for monitoring purposes while the Level A zone of 282.3
for harbor seals will be rounded to 285 m. There are no Level A take
zones applicable to other species for which take is authorized.
Table 5--Underwater Level A Harassment Threshold Decibel Levels and Corresponding Isopleths for Functional Hearing Groups During Vibratory Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
High-frequency
Low-frequency Mid-frequency cetaceans Phocid Otariid
Hearing group cetaceans cetaceans (harbor pinnipeds pinnipeds
(humpback whale, (killer whale) porpoise, (harbor seal) (Steller sea
minke whale) Dall's porpoise) lion)
--------------------------------------------------------------------------------------------------------------------------------------------------------
SELcum Threshold.............................................. 183 185 155 185 203
PTS Isopleth to threshold (m)/Impact Driving.................. 13.6 1.2 20.1 8.3 0.6
--------------------------------------------------------------------------------------------------------------------------------------------------------
*All decibel levels referenced to 1 [mu]Pa. Note all thresholds are based off root mean square (rms) levels
** PTS = Permanent Threshold Shift.
Based on these results NMFS will require a shutdown zone during
vibratory driving of 20 m for harbor porpoise, Dall's porpoise,
humpback whale and minke whale. A standard 10 m zone for killer whale,
harbor seal and Steller sea lion will also be implemented during
vibratory driving.
The disturbance zone for impact pile driving is approximately 2,090
m from the driven pile for all marine mammals. The disturbance zone for
continuous noise generated by a vibratory hammer is larger, predicted
to extend for 3,265 m from the pile. Table 6 illustrates thresholds and
isopleths for this activity that might result in Level B harassment
impacts to a marine mammal.
[[Page 17218]]
Table 6--Underwater Level B Disturbance Threshold Decibel Levels for Marine Mammals and Corresponding Isopleths
for Impact and Vibratory Pile Driving
----------------------------------------------------------------------------------------------------------------
Behavioral disruption for non-
Type of sound source Behavioral disruption for impulse pulse noise (e.g., vibratory pile
noise (e.g., impact pile driving) driving, drilling)
----------------------------------------------------------------------------------------------------------------
Threshold............................. 160 dB rms......................... 120 dB.
Isopleth to threshold (m)............. 2,090 m............................ 3,265 m.
----------------------------------------------------------------------------------------------------------------
*All decibel levels referenced to 1 [mu]Pa. Note all thresholds are based off root mean square (rms) levels.
The method used for calculating potential exposures to impact and
vibratory pile driving noise for each threshold uses local marine
mammal data sets and data from an IHA monitoring report from a similar
project in the area. It is assumed that all pilings installed at each
site would have an underwater noise disturbance equal to the piling
that causes the greatest noise disturbance (i.e., the piling furthest
from shore) installed with the method that has the largest ZOI. The
largest underwater disturbance ZOI would be produced by vibratory
driving steel piles. Note that the ZOIs for each threshold are not
spherical and are truncated by land masses on either side of the
channel which would dissipate sound pressure waves.
Since density information was not available for marine mammal
species near Gustavus, NMFS relied on two observational data sets. For
the first study, ADOT&PF hired two observers to visit the Gustavus dock
twice every day between March 7, 2016 and May 15, 2016. They scanned
for marine mammals within 2000 m for at least 30 minutes on each visit
and recorded observations. Because these data are at the project
location at the same time of year as the Spring phase of work for this
project, and in the absence of survey data, NMFS considers these data
best available for March through May.
Similar data are not available for the September through November
work phase. However, a nearby ferry terminal reconstruction project
took place in Hoonah, Alaska in the Fall of 2015. Hoonah is located 32
kilometers (km) southeast of Gustavus. An IHA was issued for the Hoonah
project which required submission of a marine mammal monitoring report
after project completion (BerberABAM 2016). The Hoonah project required
the use of both land and vessel-based observers to monitor waters that
spanned the width of Icy Strait, reaching as far north as the southern
shore of Pleasant Island. The ZOI for the Gustavus project extends to
the northern shores of Pleasant Island and westward into Icy Strait.
While the ZOIs of the Hoonah and Gustavus projects do not directly
overlap, NMFS felt that marine mammals are likely to traverse both ZOIs
in comparable numbers. Note that opportunistic sightings are not
considered abundance estimates and do not account for unseen animals in
the area and in the water. Opportunistic surveys do not have a
correction factor for those uncounted animals. Nevertheless, NMFS
considers the data from the 2016 ADOT&PF study and 2015 Hoonah
monitoring report to be the best data available, respectively, for the
March through May and September through November periods.
In order to estimate take, NMFS assumed the following:
50 days of pile driving are assumed to occur in this
exposure analysis (ADOT&PF states that between 16 and 50 days of pile
driving activity could occur).
33 days of pile driving will occur in March, April,
October, and November (non-charter season) and 17 days of pile driving
will occur in May and September (charter season).
[cir] 33 days in 4 non-charter months = 8.25 days/month outside of the
charter season
[cir] 17 days in 2 charter months = 8.5 days/month during the charter
season
The highest number of observed animals on any one day of
the month will be utilized.
The calculation for marine mammal exposures, except for Dall's
porpoise, was estimated as follows:
(the highest number of animals observed per day in a given month) x
(number of days of pile driving/removal activity in that month). The
monthly totals were added to arrive at a final estimate.
Note that with the exception of Dall's porpoise, the estimated
numbers of animal exposures in the proposed IHA Federal Register Notice
(81 FR 40852) are different from those listed in this Final IHA Notice
of Issuance. NMFS determined that the new site-specific information
contained in the 2016 ADOT&PF and 2015 Hoonah surveys was the best
available and incorporated it as part of the methodology described
above in the Final IHA. Additionally, the proposed IHA indicated that
the first period of construction would occur from September through
November of 2017 while the second period was scheduled for March
through May of 2018. The applicant opted to delay the start date until
2018. Therefore, the Final IHA authorizes take during the first
construction period from March through May of 2018 as well as the
second construction period running from September through November of
2018.
Steller Sea Lion
There are numerous Steller sea lion haulouts in Icy Strait but none
occurring in Icy Passage (Mathews et al., 2011; Tod Sebens, CSE,
Stephen Vanderhoff, SWE, Janet Neilson, NPS, personal communication).
The nearest Steller sea lion haulout sites are located on Black Rock on
the south side of Pleasant Island and Point Carolus west across the
Strait from Point Gustavus (Mathews et al., 2011). Both haulouts are
over 16 km from the Gustavus Ferry Terminal.
Steller sea lions are common in the ferry terminal area during the
charter fishing season (May to September) and are known to haul out on
the public dock (Tod Sebens, CSE, Stephen Vanderhoff, SWE, Janet
Neilson, NPS, personal communication Bruce Kruger, ADF&G, personal
communication). During the charter fishing season, Steller sea lions
begin arriving at the ferry terminal as early as 2:00 p.m. local time,
reaching maximum abundance when the charter boats return at
approximately 5:00 p.m. local time. The sea lions forage on the
carcasses of the sport fish catch and then vacate the area.
There are no density estimates of Steller sea lions available in
the action area. The best available information on the distribution of
these marine mammals in the study area comes from the 2016 ADOT&PF
study and the 2015 Hoonah monitoring report. Individuals taken would
likely be a mix of solitary adult males and females. NMFS does not
anticipate exposure of Steller sea
[[Page 17219]]
lion pups, as there are no rookeries within the action area.
NMFS has classified Steller sea lions as two distinct population
segments under the ESA--the western and eastern stocks. The western
DPS, extending from Japan around the Pacific Rim to Cape Suckling in
Alaska (144[deg] W.), was listed as endangered due to its continued
decline and lack of recovery. The eastern DPS, extending from Cape
Suckling (144[deg] W.) east to British Columbia and south to
California, was previously listed as threatened under the ESA. NMFS has
removed the eastern DPS from the list of threatened species, while the
western DPS remains listed as endangered. Note that since the actual
percentage of western DPS versus eastern DPS of Steller sea lions in
the project area is unknown, NMFS will conservatively estimate that all
individuals are from the endangered western DPS.
Based on the information presented in Table 7, NMFS has authorized
709 Level B harassment takes of Steller sea lions. No Level A takes are
authorized since the shutdown zone for Steller sea lions during impact
or vibratory pile driving is larger than the PTS isopleth.
Table 7--Estimated Monthly Total Number of Steller Sea Lions Exposed to Continuous and Impact Sourced Sounds From Pile Driving
--------------------------------------------------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year Project activity Charter season days of pile animals Estimated monthly total
occurring driving observed on a number of exposed animals
single day
--------------------------------------------------------------------------------------------------------------------------------------------------------
March 2018......................... Construction.......... No......................... 8.25 \2\ 4 33.
April 2018......................... Construction.......... No......................... 8.25 \2\ 7 57.75.
May 2018........................... Construction.......... Yes........................ 8.5 \2\ 6 51.
September 2018..................... Construction.......... Yes........................ 8.5 \1\ 26 221.
October 2018....................... Construction.......... No......................... 8.25 \1\ 33 272.25.
November 2018...................... Construction.......... No......................... 8.25 \2\ 9 74.25.
--------------------------------------------------------------------------------------------------------------------
1Total......................... ...................... ........................... .............. .............. 709.25.
709 (rounded).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
Note that the final take numbers for Steller sea lion calculated in
this Notice as well as the Environmental Assessment (EA) were slightly
different than those included in the Biological Opinion which was
drafted under the ESA. In the Biological Opinion, a total of 708 takes
were calculated while 709 were estimated for this Notice and the EA.
This occurred because the EA calculated takes based on 8.25 or 8.5 days
of pile driving per month, as applicable, while the Biological Opinion
used a single average value of 8.33 days per month, resulting in a
slightly different final take number. However, this small discrepancy
will have no practical impacts because the numbers are so close and the
take numbers were calculated using conservative assumptions, so NMFS
does not anticipate the applicant taking anywhere close to the
authorized number of takes.
Humpback Whale
NMFS used humpback whale data collected from the 2016 ADOT&PF study
and 2015 Hoonah monitoring report to estimate take using the
methodology described above. Based on the information presented in
Table 8, NMFS has authorized 600 Level B harassment takes of humpback
whales. No Level A takes are authorized since the shutdown zones are
larger than the PTS isopleths.
Table 8--Estimated Monthly Total Number of Humpback Whales Exposed to Continuous and Impact Sourced Sounds From
Pile Driving
----------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year days of pile animals Estimated monthly total number of
driving observed on a exposed animals
single day
----------------------------------------------------------------------------------------------------------------
March 2018................................ 8.25 \1\ 6 49.5.
April 2018................................ 8.25 \1\ 22 181.5.
May 2018.................................. 8.5 \1\ 10 85.
September 2018............................ 8.5 \2\ 15 127.5.
October 2018.............................. 8.25 \2\ 18 148.5.
November 2018............................. 8.25 \2\ 1 8.25.
---------------------------------------------------------------------
Total................................. .............. .............. 600.25.
600 (rounded).
----------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
[[Page 17220]]
Harbor Seal
There are no documented haulout sites for harbor seals in the
vicinity of the project. The nearest haulouts, rookeries, and pupping
grounds occur in Glacier Bay over 32 km from the ferry terminal.
However, occasionally an individual will haul out on rocks on the north
side of Pleasant Island (Stephen Vanderhoff, SWE, personal
communication). A recent study of post-breeding harbor seal migrations
from Glacier Bay demonstrates that some harbor seals traveled
extensively beyond the boundaries of Glacier Bay during the post-
breeding season (Womble and Gende 2013). Strong fidelity of individuals
for haulout sites during the breeding season was documented in this
study as well. Harbor seals are also documented in Icy Passage in the
winter and early spring (Womble and Gende 2013). Using the 2016 ADOT&PF
and 2015 Hoonah data, NMFS has authorized 675 total takes of harbor
seals as shown in Table 9. Since the PTS isopleth (282.3 m) during
impact driving is greater than the shutdown zones (100 m) NMFS is
authorizing Level A take using the following calculation:
Level A takes = (PTS isopleth - Shutdown zone)/Level B Isopleth (3,265
m) * Total Takes;
Animals in Shutdown Zone = (Shutdown zone isopleth/Level B Isopleth) *
Total Takes; and
Level B takes = Total Takes - Level A Takes - Shutdown Takes
Using these calculations, NMFS is authorizing 38 Level A and 616 Level
B harbor seal takes as shown in Table 9.
Table 9--Estimated Monthly Total Number of Harbor Seals Exposed to Continuous and Impact Sourced Sounds From
Pile Driving
----------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year days of pile animals Estimated monthly total number of
driving observed on a exposed animals
single day
----------------------------------------------------------------------------------------------------------------
March 2018................................ 8.25 \1\ 20 165.
April 2018................................ 8.25 \1\ 16 132.
May 2018.................................. 8.5 \1\ 7 59.
September 2018............................ 8.5 \2\ 22 187.
October 2018.............................. 8.25 \2\ 16 132.
November 2018............................. 8.25 \2\ 0 0.
---------------------------------------------------------------------
Total................................. .............. .............. 675.
21 Shutdown Zone.
38 Level A.
616 Level B.
654 Total.
----------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
Harbor Porpoise
Harbor porpoise are common in Icy Strait. Concentrations of harbor
porpoise were consistently found in varying habitats surrounding
Zarembo Island and Wrangell Island, and throughout the Glacier Bay and
Icy Strait regions (Dahlheim et al., 2009). These concentrations
persisted throughout the three seasons sampled. Dahlheim (2015)
indicated that 332 resident harbor porpoises occur in the Icy Strait
area, though the population has been declining across Southeast Alaska
since the early 1990's (Dahlheim et al., 2012). During a 2014 survey,
Barlow et al. (in press) observed 462 harbor porpoises in the Glacier
Bay and Icy Strait area during a three-month summer survey period. It
is estimated that harbor porpoise are observed on at least 75 percent
of whale watch excursions (75 of 100 days) during the May through
September months (Tod Sebens, CSE, Stephen Vanderhoff, SWE, personal
communication).
Using the 2016 ADOT&PF and 2015 Hoonah data, NMFS has authorized
158 total takes of harbor porpoise as shown in Table 10. Since the PTS
isopleth (628.3 m) is greater than the shutdown zone (100 m), NMFS is
authorizing Level A take. Using the same calculation utilized to derive
harbor seal takes, NMFS is authorizing 26 Level A and 127 Level B
harbor porpoise takes.
Table 10--Estimated Monthly Total Number of Harbor Porpoise Exposed to Continuous and Impact Sourced Sounds From
Pile Driving
----------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year days of pile animals Estimated monthly total number of
driving observed on a exposed animals
single day
----------------------------------------------------------------------------------------------------------------
March 2018................................ 8.25 \1\ 7 57.75.
April 2018................................ 8.25 \1\ 4 33.
May 2018.................................. 8.5 \1\ 3 25.5.
September 2018............................ 8.5 \2\ 2 17.
October 2018.............................. 8.25 \2\ 3 24.75.
November 2018............................. 8.25 \2\ 0 0.
---------------------------------------------------------------------
[[Page 17221]]
Total................................. .............. .............. 158.
5 Shutdown.
26 Level A.
127 Level B.
153 Total.
----------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
Killer Whale
Based on observations of local marine mammal specialists, the
probability of killer whales occurring in Icy Passage is low. However,
they do occur in Icy Strait and have been observed in Icy Passage.
Since there is no density information available for killer whales in
this area, NMFS used the 2016 ADOT&PF and 2015 Hoonah data sources to
estimate killer whale exposures. NMFS has authorized 126 Level B
harassment takes of killer whales as shown in Table 11. No Level A
takes are authorized since the shutdown zones for killer whales are
larger than the PTS isopleths.
Table 11--Estimated Monthly Total Number of Killer Whales Exposed to Continuous and Impact Sourced Sounds From
Pile Driving
----------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year days of pile animals Estimated monthly total number of
driving observed on a exposed animals
single day
----------------------------------------------------------------------------------------------------------------
March 2018................................ 8.25 \1\ 0 0.
April 2018................................ 8.25 \1\ 7 57.75.
May 2018.................................. 8.5 \1\ 0 0.
September 2018............................ 8.5 \2\ 8 68.
October 2018.............................. 8.25 \2\ 0 0.
November 2018............................. 8.25 \2\ 0 0.
---------------------------------------------------------------------
Total................................. .............. .............. 125.75.
126 (rounded).
----------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
Minke Whale
Based on observations of local marine mammal specialists, the
probability of minke whales occurring in Icy Passage is low. However,
they have been documented in Icy Strait and Icy Passage and could
potentially transit through the disturbance zone. The 2015 Hoonah
survey conducted from September through November did not document any
minke whales. However, results from the 2016 ADOT&PF March through May
survey showed a monthly high of one minke whale sighting per day in
April and two minke whales per day in May. An assumption of 8.25 days
of driving in April (8.25 * 1 whale) and 8.5 days in May (8.5 * 2
whales) results in 25 minke whale exposures. NMFS will also
conservatively assume that two whales may be exposed per day of driving
in March (8.25 * 2 whales). Based on these assumptions NMFS is
authorizing Level B harassment take of 42 minke whales as is shown in
Table 12. No Level A takes are authorized since the shutdown zones for
minke whales are larger than the PTS isopleth.
Table 12--Estimated Monthly Total Number of Minke Whales Exposed to Continuous and Impact Sourced Sounds From
Pile Driving
----------------------------------------------------------------------------------------------------------------
Maximum
Number of number of
Month/year days of pile animals Estimated monthly total number of
driving observed on a exposed animals
single day
----------------------------------------------------------------------------------------------------------------
March 2018................................ 8.25 2 16.5.
April 2018................................ 8.25 \1\ 1 8.25.
May 2018.................................. 8.5 \1\ 2 17.
September 2018............................ 8.5 \2\ 0 0
October 2018.............................. 8.25 \2\ 0 0.
[[Page 17222]]
November 2018............................. 8.25 \2\ 0 0.
---------------------------------------------------------------------
Total................................. .............. .............. 41.75.
42 (rounded).
----------------------------------------------------------------------------------------------------------------
\1\ These estimates come from observations made at the dock during March-May of 2016.
\2\ These estimates are from monitoring in nearby Icy Strait in 2015.
Dall's Porpoise
Dall's porpoise are documented in Icy Strait but not Icy Passage.
Dahlheim et al., (2009) found Dall's porpoise throughout Southeast
Alaska, with concentrations of animals consistently found in Icy
Strait, Lynn Canal, Stephens Passage, upper Chatham Strait, Frederick
Sound, and Clarence Strait. It is estimated that there are anywhere
from 4 to 12 sightings of Dall's porpoise in Icy Strait per season
during the May through September whale watching charter months (Tod
Sebens, CSE, Stephen Vanderhoff, SWE, personal communication). NPS
documented seven sightings in Icy Strait since 1993 in September,
October, November, April, and May. The mean group size of Dall's
porpoise in Southeast Alaska is estimated at three individuals
(Dahlheim et al., 2009).
The 2016 ADOT&PF and 2015 Hoonah studies did not record any
sightings of Dall's porpoise. However, they are occasionally sighted by
whale watching tours in Icy Strait and could potentially transit from
the Strait into the ZOI in Icy Passage. For this analysis, NMFS
conservatively assumes a maximum number of 12 group sightings per
season between May and September, which equates to 2.4 sightings per
month. Using this number it is estimated that the following number of
Dall's porpoise may be present in the disturbance zone:
Underwater exposure estimate: 2.4 group sightings/month x 3 animals/
group x 6 months of pile driving activity (March-May; September-
November) = 43.2
Since the PTS isopleth during impact driving (628.3 m) is greater
than the shutdown zone (100 m) NMFS is authorizing Level A take. Using
the same calculation utilized to derive harbor seal takes, NMFS is
authorizing take of 42 Dall's porpoise, with 7 Level A and 35 Level B
takes. According to this calculation, one porpoise would theoretically
occur in the shutdown zone and, therefore, is not counted as a take.
Analyses and Determinations
Negligible Impact Analysis
NMFS has defined negligible impact as ``an impact resulting from
the specified activity that cannot be reasonably expected to, and is
not reasonably likely to, adversely affect the species or stock through
effects on annual rates of recruitment or survival'' (50 CFR 216.103).
A negligible impact finding is based on the lack of likely adverse
effects on annual rates of recruitment or survival (i.e., population-
level effects). An estimate of the number of takes, alone, is not
enough information on which to base an impact determination. In
addition to considering the authorized number of marine mammals that
might be ``taken'' through harassment, NMFS considers other factors,
such as the likely nature of any responses (e.g., intensity, duration),
the context of any responses (e.g., critical reproductive time or
location, migration, etc.), and effects on habitat, the status of the
affected stocks, and the likely effectiveness of the mitigation.
Consistent with the 1989 preamble for NMFS's implementing regulations
(54 FR 40338; September 29, 1989), the impacts from other past and
ongoing anthropogenic activities are incorporated into these analyses
via their impacts on the environmental baseline (e.g., as reflected in
the regulatory status of the species, population size and growth rate
where known, ongoing sources of human-caused mortality, or ambient
noise levels).
To avoid repetition, the discussion of our analyses applies to all
the species listed in Table 1. There is little information about the
nature of severity of the impacts or the size, status, or structure of
any species or stock that would lead to a different analysis for this
activity.
Pile driving and pile extraction activities associated with the
Gustavus Ferry Terminal Improvements Project, as outlined previously,
have the potential to disturb or displace marine mammals. Specifically,
the specified activities may result in Level B harassment (behavioral
disturbance) for all species authorized for take, from underwater sound
generated from pile driving and removal. Level A injury may also occur
to a limited number of harbor seal, harbor porpoise and Dall's
porpoise. Potential takes could occur if individuals of these species
are present in the Level A and Level B ensonified zones when pile
driving is under way.
No serious injury or mortality is anticipated to result from this
activity. Limited take of three species of marine mammal by Level A
harassment (injury) is authorized due to potential auditory injury that
cannot reasonably be prevented through mitigation. Any take by Level A
harassment will potentially be in the form of PTS and may affect small
numbers of harbor seal, harbor porpoise and Dall's porpoise. ADOT&PF
will enact required mitigation measures to minimize Level A take.
ADOT&PF will also record all occurrences of marine mammals in specified
Level A zones. In this analysis, we considered the potential for small
numbers of three species to incur auditory injury and found that it
would not impact our preliminary determinations.
Any takes from Level B harassment will be due to behavioral
disturbance and TTS. As part of required mitigation, ADOT&PF will
employ soft start techniques during pile driving operations to allow
marine mammals to vacate the area prior to commencement of full power
driving. Pile caps will also be employed during impact pile driving to
reduce underwater noise levels.
ADOT&PF's proposed activities are localized and of relatively short
duration. The entire project area is limited to the Gustavus Ferry
Terminal area and its immediate surroundings. Specifically, the use of
impact driving
[[Page 17223]]
will be limited to an estimated maximum of 57 hours over the course of
16 to 50 days of construction. Total vibratory pile driving time is
estimated at 114 hours over the same period. While impact driving does
have the potential to cause injury to marine mammals, mitigation in the
form of shutdown zones should limit exposure to Level A thresholds.
Vibratory driving does not have significant potential to cause injury
to marine mammals due to the relatively low source levels produced and
the lack of potentially injurious source characteristics. Additionally,
no important feeding and/or reproductive areas for marine mammals are
known to be within the ensonified areas during the construction
timeframe.
The project also is not expected to have significant adverse
effects on affected marine mammals' habitat. The project activities are
limited in time and would not modify existing marine mammal habitat.
The activities may cause some fish to leave the area of disturbance,
thus temporarily impacting marine mammals' foraging opportunities in a
portion of the foraging range However, a relatively small area of
habitat may be affected, so the impacts to marine mammal habitat are
not expected to cause significant or long-term negative consequences.
Effects on individuals that are taken by Level B harassment, on the
basis of reports in the literature as well as monitoring from other
similar activities, will likely be limited to reactions such as
increased swimming speeds, increased surfacing time, or decreased
foraging (if such activity were occurring) (e.g., Thorson and Reyff
2006; Lerma 2014). Most likely, individuals will simply move away from
the sound source and be temporarily displaced from the areas of pile
driving, although even this reaction has been observed primarily only
in association with impact pile driving. In response to vibratory
driving, pinnipeds (which may become somewhat habituated to human
activity in industrial or urban waterways) have been observed to orient
towards and sometimes move towards the sound. The pile extraction and
driving activities analyzed here are similar to, or less impactful
than, numerous construction activities conducted in other similar
locations, which have taken place with no reported serious injuries or
mortality to marine mammals, and no known long-term adverse
consequences from behavioral harassment. Repeated exposures of
individuals to levels of sound that may cause Level B harassment are
unlikely to result in hearing impairment or to significantly disrupt
foraging behavior. Thus, even repeated Level B harassment of some small
subset of the overall stock is unlikely to result in any significant
realized decrease in fitness for the affected individuals, and would
not result in any adverse impact to the stock as a whole.
For pinnipeds, no rookeries are present in the project area.
Furthermore, the project area is not known to provide foraging habitat
of any special importance (other than is afforded by the known
migration of salmonids).
In summary, this negligible impact analysis is founded on the
following factors: (1) The possibility of serious injury or mortality
to authorized species may reasonably be considered discountable; (2)
the limited temporal and spatial impacts to marine mammal habitat; (3)
the absence of any major rookeries near the project area; and (4) the
presumed efficacy of the planned mitigation measures in reducing the
effects of the specified activity to the level of effecting the least
practicable impact upon the affected species. In combination, we
believe that these factors, as well as the available body of evidence
from other similar activities, demonstrate that the potential effects
of the specified activity will have only short-term effects on
individuals. The specified activity is not expected to impact rates of
recruitment or survival and will therefore not result in population-
level impacts.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the planned monitoring and
mitigation measures, NMFS finds that the total marine mammal take from
ADOT&PF's Gustavus Ferry Terminal Improvements Project will have a
negligible impact on all affected marine mammal species or stocks.
Table 13--Estimated Number of Exposures and Percentage of Stocks That May Be Subject to Level A and Level B Harassment
--------------------------------------------------------------------------------------------------------------------------------------------------------
Level A Level B Total proposed
Species authorized authorized authorized Stock(s) abundance estimate Percentage of total stock
takes takes takes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Steller Sea Lion........................ 0 709 709 50,983 (western distinct 1.43%[sol]1.39%.
population segment in Alaska)/
71,562 (eastern stock).
Humpback whale.......................... 0 600/(36*) 600/(36*) 10,103 (Central North Pacific 5.93%[sol]1.1%.
Stock)/3,264 (Mexico DPS).
Harbor Seal............................. 38 616 654 7,210 (Glacier Bay/Icy Strait). 9.07%.
Harbor Porpoise......................... 26 127 153 11,146 (Southeast Alaska)...... 1.37%.
Killer whale............................ 0 126 126 261 (Northern resident)/587 48.2% 21.4% 51.8%.
(Gulf of Alaska transient)/243
(West Coast transient).
Minke whale............................. 0 42 42 Unknown........................ Unknown.
Dall's Porpoise......................... 7 35 42 83,400......................... <0.01%.
--------------------------------------------------------------------------------------------------------------------------------------------------------
* 6.1 percent of humpbacks whales in southeast Alaska (36) are from Mexico DPS (Wade et al. 2016).
Small Numbers Analysis
Table 13 depicts the number of animals that could be exposed to
received noise levels that could cause Level A or Level B harassment
for the proposed work at the Gustavus Ferry Terminal project. The
analyses provided above represent between <0.01 and 51.8 percent of the
populations of these stocks that could be affected by harassment,
except for Minke whales since their population number is unknown. While
the Northern resident and West Coast transient killer whale takes and
percentages of stock affected appears high (48.2 percent and 51.8
percent), in reality 126 Northern resident or West Coast transient
killer whale individuals are not likely to be harassed. Instead, it is
more likely that there will be multiple takes of a smaller number of
individuals.
NMFS believes that small numbers of the West coast transient killer
whale
[[Page 17224]]
stock would be taken based on the limited region of exposure in
comparison with the known distribution of the transient stock. The West
coast transient stock ranges from Southeast Alaska to California, while
the proposed project activity would be stationary. A notable percentage
of West coast transient whales have never been observed in Southeast
Alaska. Only 155 West coast transient killer whales have been
identified as occurring in Southeast Alaska according to Dahlheim and
White (2010). The same study identified three pods of transients,
equivalent to 19 animals that remained almost exclusively in the
southern part of Southeast Alaska (i.e. Clarence Strait and Sumner
Strait). This information indicates that only a small subset of the
entire West coast Transient stock would be at risk for take in the Icy
Passage area because a sizable portion of the stock has either not been
observed in Southeast Alaska or consistently remains far south of Icy
Passage.
The Northern resident killer whale stock are most commonly seen in
the waters around the northern end of Vancouver Island, and in
sheltered inlets along B.C.'s Central and North Coasts. They also range
northward into Southeast Alaska in the winter months. Pile driving
operations are not permitted under the IHA from December through
February. It is also unlikely that such a large portion of Northern
resident killer whales with ranges of this magnitude would be
concentrated in and around Icy Passage.
There is no current abundance estimate for minke whale since
population data on this species is dated. However, the proposed take of
42 minke whales may be considered small. A visual survey for cetaceans
was conducted in the central-eastern Bering Sea in July-August 1999,
and in the southeastern Bering Sea in 2000. Results of the surveys in
1999 and 2000 provide provisional abundance estimates of 810 and 1,003
minke whales in the central-eastern and southeastern Bering Sea,
respectively (Moore et al., 2002). Additionally, line-transect surveys
were conducted in shelf and nearshore waters in 2001-2003 from the
Kenai Fjords in the Gulf of Alaska to the central Aleutian Islands.
Minke whale abundance was estimated to be 1,233 for this area (Zerbini
et al., 2006). However, these estimates cannot be used as an estimate
of the entire Alaska stock of minke whales because only a portion of
the stock's range was surveyed. (Allen and Anglis 2012). Clearly, 42
authorized takes should be considered a small number, as it constitutes
only 5.2 percent of the smallest abundance estimate generated during
the surveys just described and each of these surveys represented only a
portion of the minke whale range.
Note that the numbers of animals authorized to be taken for all
species, with the exception of Northern resident and West coast
transient killer whales, would be considered small relative to the
relevant stocks or populations even if each estimated taking occurred
to a new individual--an extremely unlikely scenario.
Based on the analysis contained herein of the likely effects of the
specified activity on marine mammals and their habitat, and taking into
consideration the implementation of the mitigation and monitoring
measures, which are expected to reduce the number of marine mammals
potentially affected by the proposed action, NMFS finds that small
numbers of marine mammals will be taken relative to the populations of
the affected species or stocks.
Impact on Availability of Affected Species for Taking for Subsistence
Uses
The proposed Gustavus Ferry Terminal improvements project will
occur near but not overlap the subsistence area used by the villages of
Hoonah and Angoon (Wolfe et al., 2013). Harbor seals and Steller sea
lions are available for subsistence harvest in this area (Wolfe et al.,
2013). There are no harvest quotas for other marine mammals found
there. The project is likely to result only in short-term, temporary
impacts to pinnipeds in the form of possible behavior changes, and is
not expected to result in the serious injury or death of any marine
mammal. Since all project activities will take place within the
immediate vicinity of the Gustavus Ferry Terminal, the project will not
have an adverse impact on the availability of marine mammals for
subsistence use at locations farther away. No disturbance or
displacement of harbor seals or sea lions from traditional hunting
areas by activities associated with the project is expected.
Based on the description of the specified activity and the proposed
mitigation and monitoring measures, NMFS has determined that there will
not be an unmitigable adverse impact on subsistence uses from ADOT&PF's
proposed activities.
National Environmental Policy Act
NMFS prepared an Environmental Assessment (EA) and analyzed the
potential impacts to marine mammals that would result from the Gustavus
Ferry Terminal construction project. A Finding of No Significant Impact
(FONSI) was signed on December 20, 2016. A copy of the EA and FONSI is
available upon request (see ADDRESSES).
Endangered Species Act (ESA)
There are two marine mammal species that are listed under the ESA
with confirmed or possible occurrence in the study area. The Mexico DPS
of humpback whale is listed as threatened and the western DPS of
Steller sea lion is listed as endangered under the Endangered Species
Act. The NMFS Alaska Regional Office Protected Resources Division
issued a Biological Opinion under section 7 of the ESA, on the issuance
of an IHA to ADOT&PF under section 101(a)(5)(D) of the MMPA by the NMFS
Permits and Conservation Division. The Biological Opinion concluded
that the proposed action is not likely to jeopardize the continued
existence of Mexico DPS humpback whales or western DPS Steller sea
lions, and is not likely to destroy or adversely modify western DPS
Steller sea lion critical habitat.
Authorization
NMFS has issued an IHA to ADOT&PF for reconstructing the existing
Gustavus Ferry Terminal located in Gustavus, Alaska, provided the
previously mentioned mitigation, monitoring, and reporting requirements
are incorporated.
Dated: April 4, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries
Service.
[FR Doc. 2017-07031 Filed 4-7-17; 8:45 am]
BILLING CODE 3510-22-P