Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to Erickson Residence Marine Access Project in Juneau, Alaska, 50387-50407 [2019-20777]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 84, Number 186 (Wednesday, September 25, 2019)]
[Notices]
[Pages 50387-50407]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-20777]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XR029


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Erickson Residence Marine Access 
Project in Juneau, Alaska

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

ACTION: Notice; proposed incidental harassment authorization; request 
for comments on proposed authorization and possible renewal.

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SUMMARY: NMFS has received a request from Jim Erickson for 
authorization to take marine mammals incidental to the Erickson 
Residence Marine Access Project in Juneau, Alaska. Pursuant to the 
Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its 
proposal to issue an incidental harassment authorization (IHA) to 
incidentally take marine mammals during the specified activities. NMFS 
is also requesting comments on a possible one-year renewal that could 
be issued under certain circumstances and if all requirements are met, 
as described in Request for Public Comments at the end of this notice. 
NMFS will consider public comments prior to making any final decision 
on the issuance of the requested MMPA authorizations and agency 
responses will be summarized in the final notice of our decision.

DATES: Comments and information must be received no later than October 
25, 2019.

ADDRESSES: Comments should be addressed to Jolie Harrison, Chief, 
Permits and Conservation Division, Office of Protected Resources, 
National Marine Fisheries Service. Physical comments should be sent to 
1315 East-West Highway, Silver Spring, MD 20910 and electronic comments 
should be sent to [email protected].
    Instructions: NMFS is not responsible for comments sent by any 
other method, to any other address or individual, or received after the 
end of the comment period. Comments received electronically, including 
all attachments, must not exceed a 25-megabyte file size. Attachments 
to electronic comments will be accepted in Microsoft Word or Excel or 
Adobe PDF file formats only. All comments received are a part of the 
public record and will generally be posted online at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act without change. All personal identifying 
information (e.g., name, address) voluntarily submitted by the 
commenter may be publicly accessible. Do not submit confidential 
business information or otherwise sensitive or protected information.

FOR FURTHER INFORMATION CONTACT: Amy Fowler, Office of Protected 
Resources, NMFS, (301) 427-8401. Electronic copies of the application 
and supporting documents, as well as a list of the references cited in 
this document, may be obtained online at: https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act. In case of problems accessing these 
documents, please call the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

    The MMPA prohibits the ``take'' of marine mammals, with certain 
exceptions. Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 
et seq.) direct the Secretary of Commerce (as delegated to NMFS) to 
allow, upon request, the incidental, but not intentional, taking of 
small numbers of marine mammals by U.S. citizens who engage in a 
specified activity (other than commercial fishing) within a specified

[[Page 50388]]

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 incidental take authorization may be 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) and will not have an unmitigable adverse impact on the 
availability of the species or stock(s) for taking for subsistence uses 
(where relevant). Further, NMFS must prescribe the permissible methods 
of taking and other ``means of effecting the least practicable adverse 
impact'' on the affected species or stocks and their habitat, paying 
particular attention to rookeries, mating grounds, and areas of similar 
significance, and on the availability of such species or stocks for 
taking for certain subsistence uses (referred to in shorthand as 
``mitigation''); and requirements pertaining to the mitigation, 
monitoring and reporting of such takings are set forth.

National Environmental Policy Act

    To comply with the National Environmental Policy Act of 1969 (NEPA; 
42 U.S.C. 4321 et seq.) and NOAA Administrative Order (NAO) 216-6A, 
NMFS must review our proposed action (i.e., the issuance of an 
incidental harassment authorization) with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (incidental harassment authorizations with 
no anticipated serious injury or mortality) of the Companion Manual for 
NOAA Administrative Order 216-6A, which do not individually or 
cumulatively have the potential for significant impacts on the quality 
of the human environment and for which we have not identified any 
extraordinary circumstances that would preclude this categorical 
exclusion. Accordingly, NMFS has preliminarily determined that the 
issuance of the proposed IHA qualifies to be categorically excluded 
from further NEPA review.
    We will review all comments submitted in response to this notice 
prior to concluding our NEPA process or making a final decision on the 
IHA request.

Summary of Request

    On May 8, 2019, NMFS received a request from Jim Erickson for an 
IHA to take marine mammals incidental to pile driving activities 
associated with a dock replacement project in Auke Bay, north of 
Juneau, Alaska. The application was deemed adequate and complete on 
August 13, 2019. Mr. Erickson's request is for take of a small number 
of eight species of marine mammal by Level A and Level B harassment. 
Neither Mr. Erickson nor NMFS expects serious injury or mortality to 
result from this activity and, therefore, an IHA is appropriate.

Description of Proposed Activity

Overview

    Mr. Erickson is proposing to replace his private moorage facility 
in Auke Bay in Juneau, Alaska to provide a safer, more accessible and 
secure dock. The old, deteriorated dock structure will be replaced with 
a new, modern moorage facility. Six timber piles will be removed using 
a vibratory hammer, and six steel pipe piles will be installed using 
vibratory and impact hammers. Drilling may be required to install the 
larger diameter steel piles. Vibratory pile removal and installation, 
impact pile installation, and drilling would introduce underwater 
sounds at levels that may result in take, by Level A and Level B 
harassment, of marine mammals in Auke Bay.

Dates and Duration

    Construction is expected to begin in the spring of 2020 but may 
occur up to December 2020. Pile driving may be intermittent during this 
period, depending on weather, construction and mechanical delays, and 
logistical constraints. Construction is expected to take up to eight 
days. Of those eight days, impact pile driving may occur on up to four 
days, vibratory pile removal and installation may occur on up to six 
days, and drilling may occur on up to two days. Work will occur during 
daylight hours only.

Specific Geographic Region

    Auke Bay is an estuary at the southern end of Lynn Canal, located 
approximately 18 kilometers (km) (11 miles (mi)) north-northwest of 
downtown Juneau. The bay is one of many that lead to a larger system of 
glacial fjords connecting various channels with the open ocean. Auke 
Bay is approximately 130 km (80.7 mi) inland from the Gulf of Alaska 
(Figure 1). Auke Bay contains several small islands and reefs within 
the 11 square kilometer (km\2\) (4.25 square mile (mi\2\)) embayment. 
While most of the bay is relatively shallow, reaching depths of 40 to 
60 meters (m) (131 to 197 feet (ft)), depths of more than 100 m (328 
ft) are found near Coghland Island on the western side of the bay. Mr. 
Erickson's dock is located on the eastern shore of Auke Bay, on the 
Mendenhall Peninsula (see Figure 1).
BILLING CODE 3510-22-P

[[Page 50389]]

[GRAPHIC] [TIFF OMITTED] TN25SE19.005

BILLING CODE 3510-22-C

Detailed Description of Specific Activity

    The Erickson Residence Marine Access Project involves demolishing 
an existing private moorage facility and replacing it with a new, 
modern facility consisting of a concrete retaining wall, an aluminum 
approach structure, and steel gangway leading to a new timber moorage 
float supported by steel piles. The six existing 12- to 16-inch (in) 
timber support piles will be extracted using a vibratory hammer. Four 
12.75-in steel pipe piles and two 20-in steel pipe piles will be 
installed in their place. All pile removal and installation activities 
will be conducted from a stationary barge platform. Pile installation 
will primarily be done using a vibratory hammer. Due to a rock 
outcropping in the project vicinity, drilling may be required for the 
two 20-in piles, as they require more embedment to reach the necessary 
capacity to withstand the high lateral loads on the float. No drilling 
is anticipated for the four 12.75-in approach bearing piles. Impact 
hammers will only be used for piles that encounter soils too dense to 
penetrate with the vibratory hammer. Table 1 provides a summary of the 
expected pile removal and installation parameters.

[[Page 50390]]



                                             Table 1--Numbers and Types of Piles To Be Installed and Removed
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                                                                                                           Duration per
                                                                                            Strikes per   pile (minutes)
                 Pile type                             Method                Number of     pile (impact     (vibratory     Piles per day      Days of
                                                                               piles         driving)        driving,         (range)        activity
                                                                                                             drilling)
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Pile installation:
    12.75-in steel........................  Vibratory installation......               4             N/A              30             2-4             1-2
    12.75-in steel........................  Impact installation.........                             150             N/A             2-4             1-2
    20-in steel...........................  Vibratory installation......               2             N/A             120             1-2             1-2
    20-in steel...........................  Impact installation.........                             150             N/A             1-2             1-2
    20-in steel...........................  Drilling....................                             N/A             300             1-2             1-2
Pile removal:
    12- to 16-in timber...................  Vibratory removal...........               6             N/A              15             3-6             1-2
                                                                         -------------------------------------------------------------------------------
        Total piles.......................  ............................              12  ..............  ..............      Total days               8
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    Demolition of the existing float and approach structures, and 
installation of the new float, approach, and concrete retaining wall 
are not expected to result in take of marine mammals and will therefore 
not be discussed further in this document.
    Proposed mitigation, monitoring, and reporting measures are 
described in detail later in this document (please see Proposed 
Mitigation and Proposed Monitoring and Reporting).

Description of Marine Mammals in the Area of Specified Activities

    Sections 3 and 4 of the application summarize available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history, of the potentially affected species. 
Additional information regarding population trends and threats may be 
found in NMFS's Stock Assessment Reports (SARs; https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessments) and more general information about these species 
(e.g., physical and behavioral descriptions) may be found on NMFS's 
website (https://www.fisheries.noaa.gov/find-species).
    Table 2 lists all species with expected potential for occurrence in 
Auke Bay and summarizes information related to the population or stock, 
including regulatory status under the MMPA and ESA and potential 
biological removal (PBR), where known. For taxonomy, we follow 
Committee on Taxonomy (2018). PBR is defined by the MMPA as the maximum 
number of animals, not including natural mortalities, that may be 
removed from a marine mammal stock while allowing that stock to reach 
or maintain its optimum sustainable population (as described in NMFS's 
SARs). While no mortality is anticipated or authorized here, PBR and 
annual serious injury and mortality from anthropogenic sources are 
included here as gross indicators of the status of the species and 
other threats.
    Marine mammal abundance estimates presented in this document 
represent the total number of individuals that make up a given stock or 
the total number estimated within a particular study or survey area. 
NMFS's stock abundance estimates for most species represent the total 
estimate of individuals within the geographic area, if known, that 
comprises that stock. For some species, this geographic area may extend 
beyond U.S. waters. All managed stocks in this region are assessed in 
NMFS's U.S. Alaska and U.S. Pacific SARs. All values presented in Table 
2 are the most recent available at the time of publication and are 
available in the 2018 SARs (Muto et al., 2019; Caretta et al., 2019).

                                              Table 2--Marine Mammals That Could Occur in the Project Area
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                                                                                                       Stock abundance
                                                                                 ESA/MMPA  status;     (CV, Nmin, most                     Annual  M/SI
           Common name                Scientific name            Stock          Strategic (Y/N) \1\    recent abundance         PBR             \3\
                                                                                                         survey) \2\
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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                                                                  Family Eschrichtiidae
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Gray whale.......................  Eschrichtius          Eastern North         -/-; N                26,960 (0.05,                   801             138
                                    robustus.             Pacific.                                    25,849, 2016).
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                                                            Family Balaenopteridae (rorquals)
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Humpback whale...................  Megaptera             Central North         T/D; Y                10,103 (0.3, 7,890,              83              26
                                    novaeangliae.         Pacific.                                    2006).
Minke whale......................  Balaenoptera          Alaska..............  -/-; N                N/A (see SAR, N/A,              UND               0
                                    acutorostrada.                                                    see SAR).
Fin whale........................  Balaenoptera          Northeast Pacific...  E/D; Y                see SAR (see SAR,               5.1             0.6
                                    physalus.                                                         see SAR, 2013).
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                                            Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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                                                                   Family Delphinidae
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Killer whale.....................  Orcinus orca........  Alaska Resident.....  -/-; N                2,347 (N/A, 2347,                24               1
                                                                                                      2012).

[[Page 50391]]

 
Killer whale.....................  Orcinus orca........  Northern Resident...  -/-; N                261 (N/A, 261,                 1.96               0
                                                                                                      2011).
Killer whale.....................  Orcinus orca........  West Coast Transient  -/-; N                243 (N/A, 243,                  2.4               0
                                                                                                      2009).
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                                                             Family Phocoenidae (porpoises)
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Harbor porpoise..................  Phocoena phocoena...  Southeast Alaska....  -/-; Y                975 (0.10; 896;                 8.9              34
                                                                                                      2012).
Dall's porpoise..................  Phocoenoides dalli..  Alaska..............  -/-; N                83,400 (0.097, N/A,             UND              38
                                                                                                      1991).
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                                                         Order Carnivora--Superfamily Pinnipedia
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                                                      Family Otariidae (eared seals and sea lions)
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Steller sea lion.................
Eumetopias jubatus...............  Eastern DPS.........  E/D; Y..............  54,267 (see SAR,      326................             252
                                                                                54,267, 2017)
Steller sea lion.................  Eumetopias jubatus..  Western DPS.........  -/-; N                41,638 (see SAR,              2,498             108
                                                                                                      41,638, 2015).
California sea lion..............  Zalophus              U.S.................  -/-; N                257,606 (N/A,                14,011           > 321
                                    californianus.                                                    233,515, 2014).
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                                                             Family Phocidae (earless seals)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Harbor seal......................  Phoca vitulina......  Lynn Canal/Stephens   -/-; N                9,478 (see SAR,                 155              50
                                                          Passage.                                    8,605, 2011).
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1--Endangered Species Act (ESA) status: Endangered (E), Threatened (T)/MMPA status: Depleted (D). A dash (-) indicates that the species is not listed
  under the ESA or designated as depleted under the MMPA. Under the MMPA, a strategic stock is one for which the level of direct human-caused mortality
  exceeds PBR or which is determined to be declining and likely to be listed under the ESA within the foreseeable future. Any species or stock listed
  under the ESA is automatically designated under the MMPA as depleted and as a strategic stock.
2--NMFS marine mammal stock assessment reports online at: www.nmfs.noaa.gov/pr/sars/. CV is coefficient of variation; Nmin is the minimum estimate of
  stock abundance. In some cases, CV is not applicable.
3--These values, found in NMFS's SARs, represent annual levels of human-caused mortality plus serious injury from all sources combined (e.g., commercial
  fisheries, ship strike). Annual M/SI often cannot be determined precisely and is in some cases presented as a minimum value or range. A CV associated
  with estimated mortality due to commercial fisheries is presented in some cases.
Note--Italicized species are not expected to be taken or proposed for authorization.

    All species that could potentially occur in the proposed survey 
areas are included in Table 2. However, the spatial and temporal 
occurrence of gray whales and fin whales in the area is such that take 
is not expected to occur, and they are not discussed further beyond the 
explanation provided here. Sightings of gray whales and fin whales are 
uncommon in the inland waters of southeast Alaska. These species are 
typically seen closer to the open waters of the Gulf of Alaska. Take of 
gray whales and fin whales has not been requested nor proposed to be 
authorized and these species are not considered further in this 
document.

Steller Sea Lion

    Steller sea lions are found throughout the northern Pacific Ocean, 
including coastal and inland waters from Russia (Kuril Islands and the 
Sea of Okhotsk), east to Alaska, and south to California. Steller sea 
lions were listed as threatened range-wide under the ESA on November 
26, 1990 (55 FR 49204) but were subsequently partitioned into the 
eastern and western Distinct Population Segments (eDPS and wDPS, 
respectively). The eDPS remained classified as threatened (62 FR 24345; 
May 5, 1997) until it was delisted in 2013 (78 FR 66139; November 4, 
2013). The wDPS (those individuals west of 144[deg] W longitude, or 
Cape Suckling, AK) was upgraded to endangered status following 
separation of the stocks, and it remains listed as endangered.
    Steller sea lions in southeast Alaska are overwhelmingly part of 
the eDPS; however, NMFS (2013) reports that an average of 917 
individuals from the wDPS move into southeast Alaska annually. Within 
southeast Alaska, abundance of wDPS individuals is higher to the north 
and west, and lower toward the south and east. Cape Ommaney and 
Frederick Sound are considered the southern limit of the range for wDPS 
animals. While it is not possible to estimate the number of wDPS 
animals that are present east of the 144[deg] W longitude boundary at 
any time, recent studies indicate that 18.1 percent of Steller sea 
lions in the Lynn Canal area may be from the wDPS (Hastings et al., 
2019).
    Steller sea lions are opportunistic predators, feeding primarily on 
a wide variety of fishes and cephalopods, including Pacific herring 
(Clupea pallasi), walleye pollock (Gadus chalogramma), capelin 
(Mallotus villosus), Pacific sand lance (Ammodytes hexapterus), Pacific 
cod (Gadus machrocephalus), salmon (Oncorhynchus spp.), and squid 
(Teuthida spp.) (Jefferson et al., 2008; Wynne et al., 2011). Steller 
sea lions do not generally eat every day, but tend to forage every one 
to two days and return to haulouts to rest between foraging trips 
(Merrick and Loughlin 1997; Rehberg et al., 2009). Most individuals 
that frequent Auke Bay haul out at Benjamin Island in Lynn Canal, but 
several other haulouts are located within 20 to 30 km (12 to 19 mi) of 
the project area.

[[Page 50392]]

    The action area is not located in or near designated critical 
habitat for the wDPS of Steller sea lions. In southeast Alaska, 
critical habitat for the wDPS includes a terrestrial zone, an aquatic 
zone, and an in-air zone that extends 3,000 ft (0.9 km) landward, 
seaward, and above, respectively, any designated major rookery and 
major haulout. The nearest designated major haulout is located at 
Benjamin Island.

California Sea Lion

    California sea lions typically breed on islands in southern 
California, western Baja California and the Gulf of California 
(Carretta et al 2017). During the winter, males commonly migrate to 
feeding grounds off California, Oregon, Washington, British Columbia 
and recently Southeast Alaska. Females and pups typically stay close to 
breeding colonies until the pups have weened. The furthest north 
females have been observed is off the coast of Washington and Oregon 
during warm water years (NMFS 2019f). California sea lions feed 
primarily offshore in coastal waters. They are opportunistic predators 
and eat a variety of prey including squid, anchovies, mackerel, 
rockfish and sardines (NMFS 2019f). A single California sea lion hauled 
out on the Statter Harbor boat ramp in Auke Bay in September of 2017.

Harbor Seal

    Harbor seals range from Baja California north along the west coasts 
of California, Oregon, Washington, British Columbia, and southeast 
Alaska; west through the Gulf of Alaska, Prince William Sound, and the 
Aleutian Islands; and north in the Bering Sea to Cape Newenham and the 
Pribilof Islands. Harbor seals occur year-round in the inside passages 
of southeast Alaska and are regularly sighted in Auke Bay, including 
Statter Harbor. Groups ranging from 10 to 52 seals may be present in 
Auke Bay, hauled out on the western side of Coghlan Island and on 
Battleship Island.
    Harbor seals forage on fish and invertebrates, including capelin, 
eulachon (Thaleichthys pacificus), cod, Pollock, flatfish, shrimp, 
octopus, and squid (Wynne 2012). They are opportunistic feeders that 
forage in marine, estuarine, freshwater habitats, adjusting their 
foraging behavior to take advantage of prey that are seasonally and 
locally abundant (Payne and Selzer 1989). Depending on prey 
availability, harbor seals conduct both shallow and deep dives while 
foraging (Tollit et al., 1997). Harbor seals usually give birth to a 
single pup between May and mid-July. Birthing locations are dispersed 
over several haulout sites and are not confined to major rookeries 
(Klinkhart et al., 2008).

Harbor Porpoise

    The Southeast Alaska stock of harbor porpoises ranges from Cape 
Suckling to the Canada border (Muto et al., 2018). Harbor porpoises 
frequent primarily coastal waters in southeast Alaska (Dalheim et al., 
2009) and occur most frequently in waters less than 100 m (328 ft) deep 
(Hobbs and Waite 2010). Harbor porpoises forage in waters less than 200 
m (656 ft) deep on small pelagic schooling fish such as herring, cod, 
pollock, octopus, smelt, and bottom-dwelling fish, occasionally feeding 
on squid and crustaceans (Bj[oslash]rge and Tolley 2009; Wynne et al., 
2011). Calving generally occurs from May to August, but can vary by 
region.

Dall's Porpoise

    Dall's porpoises are found throughout the north Pacific, from 
southern Japan to southern California and north to the Bering Sea. 
Dall's porpoises can be found in offshore, inshore, and nearshore 
habitat, but prefers waters more than 183 m (600 ft) deep (Dahlheim et 
al., 2009; Jefferson 2009). Waters over 183 m (600 ft) do not occur in 
Auke Bay but Dall's porpoises have been consistently observed in Lynn 
Canal, Stephens Passage, upper Chatham Strait, Frederick Sound, and 
Clarence Strait (Dahlheim et al., 2000). Dall's porpoises may migrate 
between inshore and offshore areas and make latitudinal movements or 
short seasonal migrations, but these movements are generally not 
consistent (Jefferson 2009). If Dall's porpoises were to occur in Auke 
Bay, they would likely be present in March or April, given seasonal 
patterns observed in nearby areas of southeast Alaska (Dahlheim et al., 
2009). Dall's porpoises often bow-ride with vessels and may occur in 
Auke Bay incidentally a few times per year.
    Dall's porpoises generally occur in groups of 2 to 20 individuals, 
but have also been recorded in groups numbering in the hundreds. Common 
prey include a variety of small, schooling fishes (such as herring and 
mackerels) and cephalopods.

Killer Whale

    Killer whales have been observed in all oceans, but the highest 
densities occur in colder and more productive waters found at high 
latitudes (NMFS 2016a). Killer whales occur along the entire Alaska 
coast, in British Columbia and Washington inland waterways, and along 
the outer coasts of Washington, Oregon, and California (NMFS 2016a). 
There are three distinct ecotypes, or forms, of killer whales 
recognized in the north Pacific: Resident, transient, and offshore. The 
three ecotypes differ morphologically, ecologically, behaviorally, and 
genetically. Eight stocks of killer whales are recognized within the 
Pacific U.S. Exclusive Economic Zone. Of those, the Alaska Resident 
stock, Northern Resident stock, and West Coast Transient stock may 
occur in the project area (Muto et al., 2018).
    The Alaska Resident stock occurs from southeast Alaska to the 
Aleutian Islands and Bering Sea. Photo-identification studies between 
2005 and 2009 identified 2,347 individuals in this stock, including 
approximately 121 in southeast Alaska (Muto et al., 2018). The Northern 
Resident stock occurs from Washington north through part of southeast 
Alaska and consists of 261 individuals (Muto et al., 2018). The West 
Coast Transient stock occurs from California north through southeast 
Alaska. Between 1975 and 2012, surveys identified 521 individual West 
Coast Transient killer whales but the minimum population estimate for 
the stock is 243 individuals (Muto et al., 2018). Dahlheim et al., 
(2009) noted a 5.2 percent annual decline in transient killer whales 
observed in southeast Alaska between 1991 and 2007.
    No systematic studies of killer whales have been conducted in or 
around Auke Bay. Killer whales were observed infrequently (on 11 of 135 
days) during monitoring in Hoonah, and most were recorded in deeper, 
offshore waters (Berger ABAM 2016). Both resident and transient killer 
whales were observed in southeast Alaska during all seasons during 
surveys between 1991 and 2007, in a variety of habitats and in all 
major waterways, including Lynn Canal, Icy Strait, Stephens Passage, 
Frederick Sound, and upper Chatham Strait (Dahlheim et al., 2009). 
There does not appear to be strong seasonal variation in abundance or 
distribution of killer whales, but Dahlheim et al., (2009) observed 
substantial variability between years during the study.
    Transient killer whales hunt and feed primarily on marine mammals, 
including harbor seals, Dall's porpoises, harbor porpoises, and sea 
lions. Resident killer whale populations in the eastern north Pacific 
feed mainly on salmonids, showing a strong preference for Chinook 
salmon (NMFS 2016a). Transient killer whales are often found in long-
term stable social units (pods) of 1 to 16 whales. Pod sizes in 
southeast Alaska vary by season, averaging 6 animals in spring, 5 in 
summer, and 4 in fall. Group sizes of transient whales

[[Page 50393]]

are generally smaller than those of resident killer whales. Resident 
killer whales occur in pods ranging from seven to 70 whales that are 
seen in association with one another more than 50 percent of the time 
(Dahlheim et al., 2009; NMFS 2016b).

Humpback Whale

    Humpback whales in the project area are from the Central North 
Pacific stock but may be of the Hawaii or Mexico DPS. The population of 
the Hawaii DPS is currently estimated at 11,398 individuals (95% 
confidence interval (CI) = 10,503--12,370) and the Mexico DPS is 
estimated at 3,264 individuals (95% CI = 2,912--3,659). The population 
of humpback whales from both the Hawaii and Mexico DPSs that are found 
in the summer feeding grounds of southeast Alaska is approximately 
6,137 individuals (95% CI = 5,352--7,038) (Wade et al., 2016). Humpback 
whales found in the project area are predominantly members of the 
Hawaii DPS, which is not listed under the ESA. However, based on a 
comprehensive photo-identification study, members of the Mexico DPS, 
which is listed as threatened, are known to occur in southeast Alaska. 
Approximately 6.1 percent (fewer than one in every 16) of all humpback 
whales in southeast Alaska and northern British Columbia are members of 
the Mexico DPS, while all others are assumed to be members of the 
Hawaii DPS (Wade et al., 2016).
    Humpback whales migrate to southeast Alaska in spring to feed after 
months of fasting in equatorial breeding grounds in Hawaii and Mexico. 
Peak abundance of humpback whales in southeast Alaska typically occurs 
during late summer to early fall. Most humpback whales begin returning 
to southern breeding grounds in fall or winter. However, due to 
temporal overlap between whales departing and returning, humpbacks can 
be found in Alaskan feeding grounds in every month of the year (Baker 
et al., 1985; Straley 1990; Wynne and Witteveen 2009). It is also 
common for some humpback whales to overwinter in areas of southeast 
Alaska. It is thought that those humpbacks that remain in southeast 
Alaska do so in response to the availability of winter schools of fish, 
such as herring (Straley 1990).
    The waters of southeast Alaska (including Auke Bay) are considered 
a biologically important area for feeding humpback whales between March 
and November (Ferguson et al., 2015). In Alaska, humpback whales filter 
feed on small crustaceans, plankton, and small fish such as walleye 
pollock, Pacific sand lance, herring, eulachon, and capelin (Witteveen 
et al., 2012). It is common to observe groups of humpback whales 
cooperatively bubble feeding.
    Humpback whales' utilization of Auke Bay is intermittent and 
irregular year-round. Recent anecdotal accounts by the Juneau Deputy 
Harbormaster indicate that humpback whale abundance in Auke Bay has 
been lower over the last 18 months than in past years (Creswell, M., 
pers. comm.). Specific micro-habitat features of Auke Bay attract 
forage fish, specifically herring, and are frequented by humpback 
whales. Although abundance is generally higher in the summer months, 
the presence of prey fish is a greater determinant of the presence of 
humpback whales than season. Teerlink (2017) identified 179 individual 
humpback whales in the Juneau area based on fluke identification.

Minke Whale

    Minke whales are found throughout the northern hemisphere in polar, 
temperate, and tropical waters (Jefferson et al., 2008). The 
International Whaling Commission has identified three minke whale 
stocks in the North Pacific: One near the Sea of Japan, a second in the 
rest of the western Pacific (west of 180[deg] W), and a third, less 
concentrated stock throughout the eastern Pacific. NMFS further splits 
this third stock between Alaska whales and resident whales of 
California, Oregon, and Washington (Muto et al., 2018). Minke whales 
are found in all Alaska waters though there are no population estimates 
for minke whales in southeast Alaska.
    In Alaska, minke whales feed primarily on euphausiids and walleye 
pollock. Minke whales are generally found in shallow, coastal waters 
within 200 m (656 ft) of shore (Zerbini et al., 2006). No information 
appears to be available on the winter occurrence of minke whales in 
southeast Alaska. Anecdotal observations suggest that minke whales do 
not enter Auke Bay, and so are expected to rarely occur in the project 
area.

Marine Mammal Hearing

    Hearing is the most important sensory modality for marine mammals 
underwater, and exposure to anthropogenic sound can have deleterious 
effects. To appropriately assess the potential effects of exposure to 
sound, it is necessary to understand the frequency ranges marine 
mammals are able to hear. Current data indicate that not all marine 
mammal species have equal hearing capabilities (e.g., Richardson et 
al., 1995; Wartzok and Ketten, 1999; Au and Hastings, 2008). To reflect 
this, Southall et al. (2007) recommended that marine mammals be divided 
into functional hearing groups based on directly measured or estimated 
hearing ranges on the basis of available behavioral response data, 
audiograms derived using auditory evoked potential techniques, 
anatomical modeling, and other data. Note that no direct measurements 
of hearing ability have been successfully completed for mysticetes 
(i.e., low-frequency cetaceans). Subsequently, NMFS (2018) described 
generalized hearing ranges for these marine mammal hearing groups. 
Generalized hearing ranges were chosen based on the approximately 65 
decibel (dB) threshold from the normalized composite audiograms, with 
the exception for lower limits for low-frequency cetaceans where the 
lower bound was deemed to be biologically implausible and the lower 
bound from Southall et al. (2007) retained. Marine mammal hearing 
groups and their associated hearing ranges are provided in Table 3.

           Table 3--Marine Mammal Hearing Groups (NMFS, 2018)
------------------------------------------------------------------------
              Hearing group                 Generalized hearing range *
------------------------------------------------------------------------
Low-frequency (LF) cetaceans (baleen      7 Hz to 35 kHz.
 whales).
Mid-frequency (MF) cetaceans (dolphins,   150 Hz to 160 kHz.
 toothed whales, beaked whales,
 bottlenose whales).
High-frequency (HF) cetaceans (true       275 Hz to 160 kHz.
 porpoises, Kogia, river dolphins,
 cephalorhynchid, Lagenorhynchus
 cruciger & L. australis).
Phocid pinnipeds (PW) (underwater) (true  50 Hz to 86 kHz.
 seals).

[[Page 50394]]

 
Otariid pinnipeds (OW) (underwater) (sea  60 Hz to 39 kHz.
 lions and fur seals).
------------------------------------------------------------------------
* Represents the generalized hearing range for the entire group as a
  composite (i.e., all species within the group), where individual
  species' hearing ranges are typically not as broad. Generalized
  hearing range chosen based on ~65 dB threshold from normalized
  composite audiogram, with the exception for lower limits for LF
  cetaceans (Southall et al. 2007) and PW pinniped (approximation).

    The pinniped functional hearing group was modified from Southall et 
al. (2007) on the basis of data indicating that phocid species have 
consistently demonstrated an extended frequency range of hearing 
compared to otariids, especially in the higher frequency range 
(Hemil[auml] et al., 2006; Kastelein et al., 2009; Reichmuth and Holt, 
2013).
    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2018) for a review of available information. 
Eight marine mammal species (five cetacean and three pinniped (two 
otariid and one phocid) species) have the reasonable potential to co-
occur with the proposed survey activities. Please refer to Table 2. Of 
the cetacean species that may be present, two are classified as low-
frequency cetaceans (i.e., all mysticete species), one is classified as 
mid-frequency cetaceans (i.e., all delphinid and ziphiid species and 
the sperm whale), and two are classified as high-frequency cetaceans 
(i.e., harbor porpoise and Kogia spp.).

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    This section includes a summary and discussion of the ways that 
components of the specified activity may impact marine mammals and 
their habitat. The Estimated Take by Incidental Harassment section 
later in this document includes a quantitative analysis of the number 
of individuals that are expected to be taken by this activity. The 
Negligible Impact Analysis and Determination section considers the 
content of this section, the Estimated Take by Incidental Harassment 
section, and the Proposed Mitigation section, to draw conclusions 
regarding the likely impacts of these activities on the reproductive 
success or survivorship of individuals and how those impacts on 
individuals are likely to impact marine mammal species or stocks.

Description of Sound Sources

    The marine soundscape is comprised of both ambient and 
anthropogenic sounds. Ambient sound is defined as the all-encompassing 
sound in a given place and is usually a composite of sound from many 
sources both near and far. The sound level of an area is defined by the 
total acoustical energy being generated by known and unknown sources. 
These sources may include physical (e.g., waves, wind, precipitation, 
earthquakes, ice, atmospheric sound), biological (e.g., sounds produced 
by marine mammals, fish, and invertebrates), and anthropogenic sound 
(e.g., vessels, dredging, aircraft, construction).
    The sum of the various natural and anthropogenic sound sources at 
any given location and time--which comprise ``ambient'' or 
``background'' sound--depends not only on the source levels (as 
determined by current weather conditions and levels of biological and 
shipping activity) but also on the ability of sound to propagate 
through the environment. In turn, sound propagation is dependent on the 
spatially and temporally varying properties of the water column and sea 
floor, and is frequency-dependent. As a result of the dependence on a 
large number of varying factors, ambient sound levels can be expected 
to vary widely over both coarse and fine spatial and temporal scales. 
Sound levels at a given frequency and location can vary by 10-20 dB 
from day to day (Richardson et al. 1995). The result is that, depending 
on the source type and its intensity, sound from the specified activity 
may be a negligible addition to the local environment or could form a 
distinctive signal that may affect marine mammals.
    In-water construction activities associated with the project would 
include impact pile driving, vibratory pile driving, vibratory pile 
removal, and DTH drilling. The sounds produced by these activities fall 
into one of two general sound types: impulsive and non-impulsive. 
Impulsive sounds (e.g., explosions, gunshots, sonic booms, impact pile 
driving) are typically transient, brief (less than 1 second), 
broadband, and consist of high peak sound pressure with rapid rise time 
and rapid decay (ANSI 1986; NIOSH 1998; ANSI 2005; NMFS 2018). Non-
impulsive sounds (e.g. aircraft, machinery operations such as drilling 
or dredging, vibratory pile driving, and active sonar systems) can be 
broadband, narrowband or tonal, brief or prolonged (continuous or 
intermittent), and typically do not have the high peak sound pressure 
with raid rise/decay time that impulsive sounds do (ANSI 1995; NIOSH 
1998; NMFS 2018). The distinction between these two sound types is 
important because they have differing potential to cause physical 
effects, particularly with regard to hearing (e.g., Ward 1997 in 
Southall et al. 2007).
    Two types of pile hammers would be used on this project: Impact and 
vibratory. Impact hammers operate by repeatedly dropping a heavy piston 
onto a pile to drive the pile into the substrate. Sound generated by 
impact hammers is characterized by rapid rise times and high peak 
levels, a potentially injurious combination (Hastings and Popper 2005). 
Vibratory hammers install piles by vibrating them and allowing the 
weight of the hammer to push them into the sediment. Vibratory hammers 
produce significantly less sound than impact hammers. Peak sound 
pressure levels (SPLs) may be 180 dB or greater, but are generally 10 
to 20 dB lower than SPLs generated during impact pile driving of the 
same-sized pile (Oestman et al. 2009). Rise time is slower, reducing 
the probability and severity of injury, and sound energy is distributed 
over a greater amount of time (Nedwell and Edwards 2002; Carlson et al. 
2005).
    Drilling would be conducted using a DTH drill inserted through the 
hollow steel piles. A DTH drill is a drill bit that drills through the 
bedrock using a pulse mechanism that functions at the bottom of the 
hole. This pulsing bit breaks up rock to allow removal of debris and 
insertion of the pile. The head extends so that the drilling takes 
place below the pile. The pulsing sounds produced by the down-the-hole 
drilling method are continuous, however this method likely increases 
sound attenuation because the noise is primarily contained within the 
steel pile and below ground rather than impact hammer driving methods 
which occur at the top of the pile (R&M 2016).
    The likely or possible impacts of Mr. Erickson's proposed activity 
on marine mammals could involve both non-acoustic and acoustic 
stressors. Potential non-acoustic stressors could

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result from the physical presence of the equipment and personnel; 
however, any impacts to marine mammals are expected to primarily be 
acoustic in nature. Acoustic stressors include effects of heavy 
equipment operation during pile installation and removal.

Acoustic Impacts

    The introduction of anthropogenic noise into the aquatic 
environment from pile installation, removal, and drilling is the 
primary means by which marine mammals may be harassed from Mr. 
Erickson's specified activity. In general, animals exposed to natural 
or anthropogenic sound may experience physical and psychological 
effects, ranging in magnitude from none to severe (Southall et al. 
2007). In general, exposure to pile driving and drilling noise has the 
potential to result in auditory threshold shifts and behavioral 
reactions (e.g., avoidance, temporary cessation of foraging and 
vocalizing, changes in dive behavior). Exposure to anthropogenic noise 
can also lead to non-observable physiological responses such an 
increase in stress hormones. Additional noise in a marine mammal's 
habitat can mask acoustic cues used by marine mammals to carry out 
daily functions such as communication and predator and prey detection. 
The effects of pile driving and drilling noise on marine mammals are 
dependent on several factors, including, but not limited to, sound type 
(e.g., impulsive vs. non-impulsive), the species, age and sex class 
(e.g., adult male vs. mom with calf), duration of exposure, the 
distance between the pile and the animal, received levels, behavior at 
time of exposure, and previous history with exposure (Wartzok et al. 
2004; Southall et al. 2007). Here we discuss physical auditory effects 
(threshold shifts) followed by behavioral effects and potential impacts 
on habitat.
    NMFS defines a noise-induced threshold shift (TS) as a change, 
usually an increase, in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). The amount of 
threshold shift is customarily expressed in dB. A TS can be permanent 
or temporary. As described in NMFS (2018), there are numerous factors 
to consider when examining the consequence of TS, including, but not 
limited to, the signal temporal pattern (e.g., impulsive or non-
impulsive), likelihood an individual would be exposed for a long enough 
duration or to a high enough level to induce a TS, the magnitude of the 
TS, time to recovery (seconds to minutes or hours to days), the 
frequency range of the exposure (i.e., spectral content), the hearing 
and vocalization frequency range of the exposed species relative to the 
signal's frequency spectrum (i.e., how animal uses sound within the 
frequency band of the signal; e.g., Kastelein et al. 2014), and the 
overlap between the animal and the source (e.g., spatial, temporal, and 
spectral).
    Permanent Threshold Shift (PTS)--NMFS defines PTS as a permanent, 
irreversible increase in the threshold of audibility at a specified 
frequency or portion of an individual's hearing range above a 
previously established reference level (NMFS 2018). Available data from 
humans and other terrestrial mammals indicate that a 40 dB threshold 
shift approximates PTS onset (see Ward et al. 1958, 1959; Ward 1960; 
Kryter et al. 1966; Miller 1974; Ahroon et al. 1996; Henderson et al. 
2008). PTS levels for marine mammals are estimates, as with the 
exception of a single study unintentionally inducing PTS in a harbor 
seal (Kastak et al. 2008), there are no empirical data measuring PTS in 
marine mammals largely due to the fact that, for various ethical 
reasons, experiments involving anthropogenic noise exposure at levels 
inducing PTS are not typically pursued or authorized (NMFS 2018).
    Temporary Threshold Shift (TTS)--A temporary, reversible increase 
in the threshold of audibility at a specified frequency or portion of 
an individual's hearing range above a previously established reference 
level (NMFS 2018). Based on data from cetacean TTS measurements (see 
Southall et al. 2007), a TTS of 6 dB is considered the minimum 
threshold shift clearly larger than any day-to-day or session-to-
session variation in a subject's normal hearing ability (Schlundt et 
al. 2000; Finneran et al. 2000, 2002). As described in Finneran (2015), 
marine mammal studies have shown the amount of TTS increases with 
cumulative sound exposure level (SELcum) in an accelerating 
fashion: At low exposures with lower SELcum, the amount of 
TTS is typically small and the growth curves have shallow slopes. At 
exposures with higher higher SELcum, the growth curves 
become steeper and approach linear relationships with the noise SEL.
    Depending on the degree (elevation of threshold in dB), duration 
(i.e., recovery time), and frequency range of TTS, and the context in 
which it is experienced, TTS can have effects on marine mammals ranging 
from discountable to serious (similar to those discussed in auditory 
masking, below). For example, a marine mammal may be able to readily 
compensate for a brief, relatively small amount of TTS in a non-
critical frequency range that takes place during a time when the animal 
is traveling through the open ocean, where ambient noise is lower and 
there are not as many competing sounds present. Alternatively, a larger 
amount and longer duration of TTS sustained during time when 
communication is critical for successful mother/calf interactions could 
have more serious impacts. We note that reduced hearing sensitivity as 
a simple function of aging has been observed in marine mammals, as well 
as humans and other taxa (Southall et al. 2007), so we can infer that 
strategies exist for coping with this condition to some degree, though 
likely not without cost.
    Currently, TTS data only exist for four species of cetaceans 
(bottlenose dolphin (Tursiops truncatus), beluga whale (Delphinapterus 
leucas), harbor porpoise, and Yangtze finless porpoise (Neophocoena 
asiaeorientalis)) and five species of pinnipeds exposed to a limited 
number of sound sources (i.e., mostly tones and octave-band noise) in 
laboratory settings (Finneran 2015). TTS was not observed in trained 
spotted (Phoca largha) and ringed (Pusa hispida) seals exposed to 
impulsive noise at levels matching previous predictions of TTS onset 
(Reichmuth et al. 2016). In general, harbor seals and harbor porpoises 
have a lower TTS onset than other measured pinniped or cetacean species 
(Finneran 2015). Additionally, the existing marine mammal TTS data come 
from a limited number of individuals within these species. No data are 
available on noise-induced hearing loss for mysticetes. For summaries 
of data on TTS in marine mammals or for further discussion of TTS onset 
thresholds, please see Southall et al. (2007), Finneran and Jenkins 
(2012), Finneran (2015), and Table 5 in NMFS (2018). Installing piles 
requires a combination of impact pile driving and vibratory pile 
driving, and may require DTH drilling. For the project, these 
activities would not occur at the same time and there would likely be 
pauses in activities producing the sound during each day. Given these 
pauses and that many marine mammals are likely moving through the 
action area and not remaining for extended periods of time, the 
potential for TS declines.
    Behavioral Harassment--Exposure to noise from pile driving and 
removal also has the potential to behaviorally disturb marine mammals. 
Available studies show wide variation in response to underwater sound; 
therefore, it is difficult to predict specifically how any

[[Page 50396]]

given sound in a particular instance might affect marine mammals 
perceiving the signal. If a marine mammal does react briefly to an 
underwater sound by changing its behavior or moving a small distance, 
the impacts of the change are unlikely to be significant to the 
individual, let alone the stock or population. However, if a sound 
source displaces marine mammals from an important feeding or breeding 
area for a prolonged period, impacts on individuals and populations 
could be significant (e.g., Lusseau and Bejder 2007; Weilgart 2007; NRC 
2005).
    Disturbance may result in changing durations of surfacing and 
dives, number of blows per surfacing, or moving direction and/or speed; 
reduced/increased vocal activities; changing/cessation of certain 
behavioral activities (such as socializing or feeding); visible startle 
response or aggressive behavior (such as tail/fluke slapping or jaw 
clapping); avoidance of areas where sound sources are located. 
Pinnipeds may increase their haul out time, possibly to avoid in-water 
disturbance (Thorson and Reyff 2006). Behavioral responses to sound are 
highly variable and context-specific and any reactions depend on 
numerous intrinsic and extrinsic factors (e.g., species, state of 
maturity, experience, current activity, reproductive state, auditory 
sensitivity, time of day), as well as the interplay between factors 
(e.g., Richardson et al. 1995; Wartzok et al. 2003; Southall et al. 
2007; Weilgart 2007; Archer et al. 2010). Behavioral reactions can vary 
not only among individuals but also within an individual, depending on 
previous experience with a sound source, context, and numerous other 
factors (Ellison et al. 2012), and can vary depending on 
characteristics associated with the sound source (e.g., whether it is 
moving or stationary, number of sources, distance from the source). In 
general, pinnipeds seem more tolerant of, or at least habituate more 
quickly to, potentially disturbing underwater sound than do cetaceans, 
and generally seem to be less responsive to exposure to industrial 
sound than most cetaceans. Please see Appendices B-C of Southall et al. 
(2007) for a review of studies involving marine mammal behavioral 
responses to sound.
    Disruption of feeding behavior can be difficult to correlate with 
anthropogenic sound exposure, so it is usually inferred by observed 
displacement from known foraging areas, the appearance of secondary 
indicators (e.g., bubble nets or sediment plumes), or changes in dive 
behavior. As for other types of behavioral response, the frequency, 
duration, and temporal pattern of signal presentation, as well as 
differences in species sensitivity, are likely contributing factors to 
differences in response in any given circumstance (e.g., Croll et al. 
2001; Nowacek et al. 2004; Madsen et al. 2006; Yazvenko et al. 2007). A 
determination of whether foraging disruptions incur fitness 
consequences would require information on or estimates of the energetic 
requirements of the affected individuals and the relationship between 
prey availability, foraging effort and success, and the life history 
stage of the animal.
    In 2016, ADOT&PF documented observations of marine mammals during 
construction activities (i.e., pile driving and down-hole drilling) at 
the Kodiak Ferry Dock (see 80 FR 60636 for Final IHA Federal Register 
notice). In the marine mammal monitoring report for that project (ABR 
2016), 1,281 Steller sea lions were observed within the behavioral 
disturbance zone during pile driving or drilling (i.e., documented as 
Level B harassment take). Of these, 19 individuals demonstrated an 
alert behavior, 7 were fleeing, and 19 swam away from the project site. 
All other animals were engaged in activities such as milling, foraging, 
or fighting and did not change their behavior. In addition, two sea 
lions approached within 20 meters of active vibratory pile driving 
activities. Three harbor seals were observed within the disturbance 
zone during pile driving activities; none of them displayed disturbance 
behaviors. Fifteen killer whales and three harbor porpoise were also 
observed within the Level B harassment zone during pile driving. The 
killer whales were travelling or milling while all harbor porpoises 
were travelling. No signs of disturbance were noted for either of these 
species. Given the similarities in activities and habitat and the fact 
the same species are involved, we expect similar behavioral responses 
of marine mammals to the specified activity. That is, disturbance, if 
any, is likely to be temporary and localized (e.g., small area 
movements). Monitoring reports from other recent pile driving projects 
have observed similar behaviors.
    Masking--Sound can disrupt behavior through masking, or interfering 
with, an animal's ability to detect, recognize, or discriminate between 
acoustic signals of interest (e.g., those used for intraspecific 
communication and social interactions, prey detection, predator 
avoidance, navigation) (Richardson et al. 1995). Masking occurs when 
the receipt of a sound is interfered with by another coincident sound 
at similar frequencies and at similar or higher intensity, and may 
occur whether the sound is natural (e.g., snapping shrimp, wind, waves, 
precipitation) or anthropogenic (e.g., pile driving, shipping, sonar, 
seismic exploration) in origin. The ability of a noise source to mask 
biologically important sounds depends on the characteristics of both 
the noise source and the signal of interest (e.g., signal-to-noise 
ratio, temporal variability, direction), in relation to each other and 
to an animal's hearing abilities (e.g., sensitivity, frequency range, 
critical ratios, frequency discrimination, directional discrimination, 
age or TTS hearing loss), and existing ambient noise and propagation 
conditions. Masking of natural sounds can result when human activities 
produce high levels of background sound at frequencies important to 
marine mammals. Conversely, if the background level of underwater sound 
is high (e.g. on a day with strong wind and high waves), an 
anthropogenic sound source would not be detectable as far away as would 
be possible under quieter conditions and would itself be masked. Auke 
Bay is home to a busy ferry terminal as well as moorage for small 
private vessels that transit the area on a regular basis; therefore, 
background sound levels in the harbor are already elevated.
    Airborne Acoustic Effects--Pinnipeds that occur near the project 
site could be exposed to airborne sounds associated with pile driving 
and removal that have the potential to cause behavioral harassment, 
depending on their distance from pile driving activities. Cetaceans are 
not expected to be exposed to airborne sounds that would result in 
harassment as defined under the MMPA.
    Airborne noise would primarily be an issue for pinnipeds that are 
swimming or hauled out near the project site within the range of noise 
levels exceeding the acoustic thresholds. We recognize that pinnipeds 
in the water could be exposed to airborne sound that may result in 
behavioral harassment when looking with their heads above water. Most 
likely, airborne sound would cause behavioral responses similar to 
those discussed above in relation to underwater sound. For instance, 
anthropogenic sound could cause hauled-out pinnipeds to exhibit changes 
in their normal behavior, such as reduction in vocalizations, or cause 
them to temporarily abandon the area and move further from the source. 
However, these animals would previously have been `taken' because of 
exposure to underwater sound above the behavioral harassment 
thresholds, which are in all cases larger than those

[[Page 50397]]

associated with airborne sound. Thus, the behavioral harassment of 
these animals is already accounted for in these estimates of potential 
take. Therefore, we do not believe that authorization of incidental 
take resulting from airborne sound for pinnipeds is warranted, and 
airborne sound is not discussed further here.

Marine Mammal Habitat Effects

    Mr. Erickson's construction activities could have localized, 
temporary impacts on marine mammal habitat by increasing in-water sound 
pressure levels and slightly decreasing water quality. Construction 
activities are of short duration and would likely have temporary 
impacts on marine mammal habitat through increases in underwater sound. 
Increased noise levels may affect acoustic habitat (see masking 
discussion above) and adversely affect marine mammal prey in the 
vicinity of the project area (see discussion below). During pile 
driving and drilling, elevated levels of underwater noise would 
ensonify the bay where both fish and mammals may occur and could affect 
foraging success.
    In-water pile installation, pile removal, and drilling would also 
cause short-term effects on water quality due to increased turbidity. 
Local currents are anticipated to disburse suspended sediments produced 
by project activities at moderate to rapid rates depending on tidal 
stage. Mr. Erickson would employ standard construction best management 
practices, thereby reducing any impacts. Considering the nature and 
duration of the effects, combined with the measures to reduce 
turbidity, the impact from increased turbidity levels is expected to be 
discountable.

In-Water Construction Effects on Potential Foraging Habitat

    The area likely impacted by the project is relatively small 
compared to the available habitat in the surrounding waters of Lynn 
Canal. Although Auke Bay is included in the designated Biologically 
Important Area for feeding humpback whales, humpback foraging efforts 
within Auke Bay itself are intermittent and irregular across seasons. 
Construction activities may temporarily increase turbidity resulting 
from suspended sediments. Any increases would be temporary, localized, 
and minimal. Mr. Erickson must comply with state water quality 
standards during these operations by limiting the extent of turbidity 
to the immediate project area. In general, turbidity associated with 
pile installation is localized to about a 25-foot radius around the 
pile (Everitt et al. 1980). Cetaceans are not expected to enter the 
harbor and be close enough to the project pile driving areas to 
experience effects of turbidity, and any pinnipeds would likely be 
transiting the area and could avoid localized areas of turbidity. 
Therefore, the impact from increased turbidity levels is expected to be 
discountable to marine mammals. Furthermore, pile driving and removal 
at the project site would not obstruct movements or migration of marine 
mammals.
    Avoidance by potential prey (i.e., fish) of the immediate area due 
to the temporary loss of this foraging habitat is also possible. The 
duration of fish avoidance of this area after pile driving stops is 
unknown, but a rapid return to normal recruitment, distribution and 
behavior is anticipated. Any behavioral avoidance by fish of the 
disturbed area would still leave significantly large areas of fish and 
marine mammal foraging habitat in the nearby vicinity in Lynn Canal.
    The duration of the construction activities is relatively short, 
with pile driving activities expected to take only eight days. Each 
day, construction would occur for only a few hours during the day. 
Impacts to habitat and prey are expected to be temporary and minimal 
based on the short duration of activities.

In-Water Construction Effects on Potential Prey (Fish)

    Construction activities would produce continuous (i.e., vibratory 
pile driving) and pulsed (i.e. impact driving) sounds. Fish react to 
sounds that are especially strong and/or intermittent low-frequency 
sounds. Short duration, sharp sounds can cause overt or subtle changes 
in fish behavior and local distribution. Hastings and Popper (2005) 
identified several studies that suggest fish may relocate to avoid 
certain areas of sound energy. Additional studies have documented 
effects of pile driving on fish, although several are based on studies 
in support of large, multiyear bridge construction projects (e.g., 
Scholik and Yan 2001, 2002; Popper and Hastings 2009). Sound pulses at 
received levels of 160 dB may cause subtle changes in fish behavior. 
SPLs of 180 dB may cause noticeable changes in behavior (Pearson et al. 
1992; Skalski et al. 1992). SPLs of sufficient strength have been known 
to cause injury to fish and fish mortality.
    The most likely impact to fish from pile driving and drilling 
activities at the project area would be temporary behavioral avoidance 
of the area. The duration of fish avoidance of this area after pile 
driving stops is unknown, but a rapid return to normal recruitment, 
distribution and behavior is anticipated. In general, impacts to marine 
mammal prey species are expected to be minor and temporary due to the 
short timeframe for the project.
    Construction activities, in the form of increased turbidity, have 
the potential to adversely affect fish in the project area. Increased 
turbidity is expected to occur in the immediate vicinity (on the order 
of 10 feet or less) of construction activities. However, suspended 
sediments and particulates are expected to dissipate quickly within a 
single tidal cycle. Given the limited area affected and high tidal 
dilution rates any effects on fish are expected to be minor or 
negligible. In addition, best management practices would be in effect, 
which would limit the extent of turbidity to the immediate project 
area.
    In summary, given the short daily duration of sound associated with 
individual pile driving and drilling events and the relatively small 
areas being affected, pile driving activities associated with the 
proposed action are not likely to have a permanent, adverse effect on 
any fish habitat, or populations of fish species. Thus, we conclude 
that impacts of the specified activity are not likely to have more than 
short-term adverse effects on any prey habitat or populations of prey 
species. Further, any impacts to marine mammal habitat are not expected 
to result in significant or long-term consequences for individual 
marine mammals, or to contribute to adverse impacts on their 
populations.

Estimated Take

    This section provides an estimate of the number of incidental takes 
proposed for authorization through this IHA, which will inform both 
NMFS' consideration of ``small numbers'' and the negligible impact 
determination.
    Harassment is the only type of take expected to result from these 
activities. 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).
    Authorized takes would primarily be by Level B harassment, as use 
of the vibratory and impact pile hammers and drill has the potential to 
result in disruption of behavioral patterns for

[[Page 50398]]

individual marine mammals. There is also some potential for auditory 
injury (Level A harassment) to result, primarily for high frequency 
cetacean species and phocids because predicted auditory injury zones 
are larger than for other hearing groups. Auditory injury is unlikely 
to occur for other groups. The proposed mitigation and monitoring 
measures are expected to minimize the severity of such taking to the 
extent practicable.
    As described previously, no mortality is anticipated or proposed to 
be authorized for this activity. Below we describe how the take is 
estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which NMFS believes the best available science 
indicates marine mammals will be behaviorally harassed or incur some 
degree of permanent hearing impairment; (2) the area or volume of water 
that will be ensonified above these levels in a day; (3) the density or 
occurrence of marine mammals within these ensonified areas; and, (4) 
and the number of days of activities. We note that while these basic 
factors can contribute to a basic calculation to provide an initial 
prediction of takes, additional information that can qualitatively 
inform take estimates is also sometimes available (e.g., previous 
monitoring results or average group size). Below, we describe the 
factors considered here in more detail and present the proposed take 
estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of underwater sound above 
which exposed marine mammals would be reasonably expected to be 
behaviorally harassed (equated to Level B harassment) or to incur PTS 
of some degree (equated to Level A harassment).
    Level B Harassment for non-explosive sources--Though significantly 
driven by received level, the onset of behavioral disturbance from 
anthropogenic noise exposure is also informed to varying degrees by 
other factors related to the source (e.g., frequency, predictability, 
duty cycle), the environment (e.g., bathymetry), and the receiving 
animals (hearing, motivation, experience, demography, behavioral 
context) and can be difficult to predict (Southall et al., 2007, 
Ellison et al., 2012). Based on what the available science indicates 
and the practical need to use a threshold based on a factor that is 
both predictable and measurable for most activities, NMFS uses a 
generalized acoustic threshold based on received level to estimate the 
onset of behavioral harassment. NMFS predicts that marine mammals are 
likely to be behaviorally harassed in a manner we consider Level B 
harassment when exposed to underwater anthropogenic noise above 
received levels of 120 dB re 1 [mu]Pa (rms) for continuous (e.g., 
vibratory pile-driving, drilling) and above 160 dB re 1 [mu]Pa (rms) 
for non-explosive impulsive (e.g., seismic airguns) or intermittent 
(e.g., scientific sonar) sources.
    Mr. Erickson's proposed activity includes the use of continuous 
(vibratory pile driving and removal, drilling) and impulsive (impact 
pile driving) sources, and therefore the 120 and 160 dB re 1 [mu]Pa 
(rms) thresholds are applicable.
    Level A harassment for non-explosive sources--NMFS' Technical 
Guidance for Assessing the Effects of Anthropogenic Sound on Marine 
Mammal Hearing (Version 2.0) (Technical Guidance, 2018) identifies dual 
criteria to assess auditory injury (Level A harassment) to five 
different marine mammal groups (based on hearing sensitivity) as a 
result of exposure to noise from two different types of sources 
(impulsive or non-impulsive). Mr. Erickson's proposed activity includes 
the use of impulsive (impact pile driving) and non-impulsive (vibratory 
pile driving and removal, drilling) source.
    These thresholds are provided in Table 4. The references, analysis, 
and methodology used in the development of the thresholds are described 
in NMFS 2018 Technical Guidance, which may be accessed at https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-acoustic-technical-guidance.

                     Table 4--Thresholds Identifying the Onset of Permanent Threshold Shift
----------------------------------------------------------------------------------------------------------------
                                                   PTS onset acoustic thresholds \*\  (received level)
----------------------------------------------------------------------------------------------------------------
             Hearing group                        Impulsive                         Non-impulsive
----------------------------------------------------------------------------------------------------------------
Low-Frequency (LF) Cetaceans...........  Cell 1: Lpk,flat: 219 dB;   Cell 2: LE,LF,24h: 199 dB.
                                          LE,LF,24h: 183 dB.
Mid-Frequency (MF) Cetaceans...........  Cell 3: Lpk,flat: 230 dB;   Cell 4: LE,MF,24h: 198 dB.
                                          LE,MF,24h: 185 dB.
High-Frequency (HF) Cetaceans..........  Cell 5: Lpk,flat: 202 dB;   Cell 6: LE,HF,24h: 173 dB.
                                          LE,HF,24h: 155 dB.
Phocid Pinnipeds (PW) (Underwater).....  Cell 7: Lpk,flat: 218 dB;   Cell 8: LE,PW,24h: 201 dB.
                                          LE,PW,24h: 185 dB.
Otariid Pinnipeds (OW) (Underwater)....  Cell 9: Lpk,flat: 232 dB;   Cell 10: LE,OW,24h: 219 dB.
                                          LE,OW,24h: 203 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.

Ensonified Area

    Here, we describe operational and environmental parameters of the 
activity that will feed into identifying the area ensonified above the 
acoustic thresholds, which include source levels and transmission loss 
coefficient.
    The sound field in the project area is the existing background 
noise plus additional construction noise from the proposed project. 
Marine mammals are expected to be affected via sound generated by the 
primary components of the project (i.e., impact pile driving, vibratory 
pile driving and removal). The area ensonified above the thresholds for 
harassment is governed by the topography of Auke Bay and the various 
islands located within and around the

[[Page 50399]]

bay. The eastern part of Auke Bay is acoustically shadowed by Auke 
Cape, while Portland Island, Coghlan Island, Suedla Island, and Spuhn 
Island would inhibit sound transmission from reaching the more open 
waters toward Mansfield Peninsula (see Figure 2 in the IHA 
application). Additionally, vessel traffic and other commercial and 
industrial activities in the project area may contribute to elevated 
background noise levels which may mask sounds produced by the project.
    The project includes vibratory removal of timber piles, vibratory 
and impact installation of steel pipe piles, and drilling. Source 
levels for these activities are based on reviews of measurements of the 
same or similar types and dimensions of piles available in the 
literature. Source levels for each activity are presented in Table 5. 
The source level for vibratory removal of timber piles is from in-water 
measurements generated by the Greenbusch Group (2018) from the Seattle 
Pier 62 project (83 FR 39709; April 10, 2018). Hydroacoustic monitoring 
results from Pier 62 determined unweighted rms ranging from 140 dB to 
169 dB. NMFS analyzed source measurements at different distances for 
all 63 individual timber piles that were removed at Pier 62 and 
normalized the values to 10 m. The results showed that the median is 
152 dB SPLrms. There are no literature source levels for vibratory 
installation of 12.75-in steel piles so source levels from vibratory 
installation of 12-in steel piles from the Caltrans Compendium of Pile 
Driving Sound Data were used as a proxy (Caltrans 2015). Similarly, as 
no literature source levels exist for vibratory installation of 20-in 
steel piles, hydroacoustic measurements of vibratory installation of 
24-in steel piles from the U.S. Navy's Test Pile Project were used as a 
proxy (Navy 2015). Source levels for impact installation of 12.75-in 
piles were determined by using Caltrans measurements of impact 
installation of 12-in steel piles as a proxy (Caltrans 2015). Source 
levels for impact installation of 20-in piles are from installation of 
20-in piles in the Columbia River, in similar water depths (Yurk et 
al., 2016). Source levels for drilling are proxy from median measured 
source level from drilling of 24-in diameter piles at the Kodiak Ferry 
Terminal (Denes et al., 2016, Table 72).

                                                                 Table 5--Sound Source Levels for Pile Sizes and Driving Methods
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         Source level
                Pile size                             Method           ------------------------------------------------                             Literature source
                                                                            dB RMS          dB Peak         dB SEL
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
12.75-in steel...........................  Vibratory..................             155             171             155  Caltrans 2015 (proxy from 12-in).
20-in steel..............................  Vibratory..................             161              --              --  Navy 2015 (proxy from 24-in).
12- to 16-in timber......................  Vibratory..................             152              --              --  Greenbusch Group 2018.
20-in steel..............................  Drilling...................           166.2              --              --  Denes et al., 2016 (proxy from 24-in).
12.75-in steel...........................  Impact.....................             177             192              --  Caltrans 2015 (proxy from 12-in).
20-in steel..............................  Impact.....................             190             205             175  Yurk et al., 2016.
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
--indicates source level not reported.

    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 (R 1/R 2), where

TL = transmission loss in dB
B = transmission loss coefficient
R 1= the distance of the modeled SPL from the driven 
pile, and
R 2= the distance from the driven pile of the initial 
measurement

    A practical spreading value of fifteen is often used under 
conditions, such as Auke Bay, where water increases with depth as the 
receiver moves away from the shoreline, resulting in an expected 
propagation environment that would lie between spherical and 
cylindrical spreading loss conditions. Practical spreading loss is 
assumed here.

               Table 6--Pile Driving Source Levels and Distances to Level B Harassment Thresholds
----------------------------------------------------------------------------------------------------------------
                                                                   Source level       Level B
                                                                  at 10 m (dB re   threshold (dB    Distance to
          Pile size and type                     Method             1 [micro]Pa   re 1 [micro]Pa      level B
                                                                       rms)            rms)        threshold (m)
----------------------------------------------------------------------------------------------------------------
12.75-in steel........................  Vibratory...............             155             120           2,154
20-in steel...........................  Vibratory...............             161             120           5,412
12- to 16-in timber...................  Vibratory...............             152             120           1,359
20-in steel...........................  Drilling................           166.2             120          12,023
12.75-in steel........................  Impact..................             177             160             136
20-in steel...........................  Impact..................             190             160           1,000
----------------------------------------------------------------------------------------------------------------

    When the NMFS Technical Guidance (2016) was published, in 
recognition of the fact that ensonified area/volume could be more 
technically challenging to predict because of the duration component in 
the new thresholds, we developed a User Spreadsheet that includes tools 
to help predict a simple isopleth that can be used in conjunction with 
marine mammal density or occurrence to help predict takes. We note that 
because of some of the assumptions included in the methods used for 
these tools, we anticipate that isopleths produced are typically going 
to be overestimates of some degree, which may result in some degree of 
overestimate of Level A harassment take. However, these tools offer the 
best way to predict appropriate isopleths when more sophisticated 3D 
modeling methods are not available, and NMFS continues to develop ways 
to quantitatively refine these tools, and will qualitatively address 
the output where appropriate. For stationary sources (such as pile 
drivers), NMFS

[[Page 50400]]

User Spreadsheet predicts the closest distance at which, if a marine 
mammal remained at that distance the whole duration of the activity, it 
would not incur PTS. Inputs used in the User Spreadsheet, and the 
resulting isopleths are reported below (Table 7). Mr. Erickson 
anticipates that the number of piles installed or removed per day may 
vary due to environmental conditions and equipment availability. To 
calculate the Level A harassment isopleths in the User Spreadsheet, Mr. 
Anderson conservatively entered the maximum number of piles that may be 
installed in a day.

                                                  Table 7--User Spreadsheet Input Parameters Used for Calculating Level A Harassment Isopleths
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Weighting                                                                        Driving
                                                                    Spreadsheet       factor       Source level     Propagation       Strike        Strikes per    duration for    Max piles per
                            Activity                                 tab used       adjustment        at 10 m         (xLogR)     duration (sec)       pile         single pile         day
                                                                                       (kHz)                                                                          (hours)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Timber vibratory removal........................................             A.1             2.5      152 dB rms              15             N/A             N/A            0.25               6
12.75-in vibratory install......................................             A.1             2.5      155 dB rms              15             N/A             N/A               1               4
20-in vibratory install.........................................             A.1             2.5      161 dB rms              15             N/A             N/A               2               2
DTH Drilling....................................................             A.1             2.5           166.2              15             N/A             N/A               5               2
12.75-in impact.................................................             E.1               2      177 dB rms              15            0.05             150             N/A               4
20-in impact....................................................             E.1               2      175 dB SEL              15             N/A             150             N/A               2
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
N/A indicates not applicable.


                          Table 8--Calculated Distances to Level A Harassment Isopleths
----------------------------------------------------------------------------------------------------------------
                                                            Level A harassment zone (m)
            Activity             -------------------------------------------------------------------------------
                                   LF cetaceans    MF cetaceans    HF cetaceans       Phocids        Otariids
----------------------------------------------------------------------------------------------------------------
Timber vibratory removal........             2.2             0.2             3.3             1.4             0.1
12.75-in vibratory install......             6.9             0.6            10.1             4.2             0.3
20-in vibratory install.........            17.2             1.5            25.4            10.5             0.7
DTH Drilling....................            70.4             6.2           104.1            42.8             3.0
12.75-in impact.................            38.4             1.4            45.7            20.5             1.5
20-in impact....................           131.1             4.7           156.1            70.1             5.1
----------------------------------------------------------------------------------------------------------------

Marine Mammal Occurrence and Take Calculation and Estimation

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals and describe how it is 
brought together with the information above to produce a quantitative 
take estimate. When available, peer-reviewed scientific publications 
were used to estimate marine mammal abundance in the project area. 
However, scientific surveys and resulting data such as population 
estimates, densities, and other quantitative information are lacking 
for most marine mammal populations and most areas of southeast Alaska, 
including Auke Bay. Therefore, Mr. Erickson gathered qualitative 
information from discussions with knowledgeable local people in the 
Auke Bay area, including biologists, the harbormaster, a tour operator, 
and other individuals familiar with marine mammals in the Auke Bay 
area.
    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate. Because reliable 
densities are not available, the applicant requests take based on the 
maximum number of animals that may occur in the harbor per day 
multiplied by the number of days of the activity.

Steller Sea Lion

    Steller sea lions are common within Auke Bay but generally only 
occur in the area during winter. Most individuals that frequent Auke 
Bay haul out at Benjamin Island in Lynn Canal. The Auke Bay boating 
community observes Steller sea lions transiting between Auke Bay and 
Benjamin Island regularly during winter. Steller sea lions are not 
known to haul out on any beaches or structures within Auke Bay, but 
animals have been observed foraging within Auke Bay, and may rest in 
large raft groups in the water. Groups as large as 121 individuals have 
been observed in Auke Bay (Ridgway pers. observ.).
    Mr. Erickson estimates that one large group (121 individuals) may 
be exposed to project-related underwater noise daily on 8 days of pile 
installation and removal activities, for a total of 968 exposures. As 
stated above, approximately 18.1 percent of Steller sea lions present 
in Auke Bay are expected to belong to the wDPS, for a total of 175 
exposures of wDPS Steller sea lions and 793 exposures of eDPS Steller 
sea lions.
    The largest Level A harassment zone for otariid pinnipeds extends 
5.1 m from the source (Table 8). Mr. Erickson is planning to implement 
a minimum shutdown zone of 10 m during all pile driving activities, 
(see Proposed Mitigation section), which is expected to eliminate the 
potential for Level A take of Steller sea lions. Therefore, no takes of 
Steller sea lions by Level A harassment were requested or are proposed 
to be authorized.

California Sea Lion

    California sea lions are rare in Southeast Alaska, but a single 
California sea lion was observed hauled out in Statter Harbor in 
September of 2017. While Statter Harbor is acoustically shadowed by the 
topography of Auke Bay and will not be ensonified above the Level B 
behavioral harassment threshold, a California sea lion could enter the 
Level B harassment zone within Auke Bay to forage. Therefore, Mr. 
Erickson estimates that a single California sea lion may enter the 
Level B harassment zone on each of the eight days of pile driving, for 
a total of eight exposures.
    The largest Level A harassment zone for otariid pinnipeds extends 
5.1 m from the source (Table 8). Mr. Erickson is planning to implement 
a minimum shutdown zone of 10 m during all pile driving activities, 
(see Proposed Mitigation section), which is expected to eliminate the 
potential for Level A take of California sea lions. Therefore, no takes 
of California sea lions by Level A harassment were requested or are 
proposed to be authorized.

[[Page 50401]]

Harbor Seal

    Harbor seals are commonly sighted in the waters of the inside 
passages throughout southeast Alaska. Seals occur year-round within the 
project area and are regularly sighted in Auke Bay, including Statter 
Harbor.
    Up to 52 seals have been observed hauled out on a dock at 
Fisherman's Bend within Statter Harbor (Ridgway unpubl. data) which is 
acoustically sheltered from the proposed pile driving activities, but 
it is assumed that these animals may leave the dock to forage within 
Auke Bay and may be exposed to noise levels in excess of the Level B 
harassment thresholds upon entering the water. Mr. Erickson estimates 
up to 52 harbor seals could be exposed to elevated sound levels on each 
day of pile driving, for a total of 416 exposures.
    The largest Level A harassment zone for phocid pinnipeds results 
from impact installation of 20-in piles and extends 70.1 m from the 
pile (Table 8). There are no haulouts located within the Level A 
harassment zone and although it is unlikely that harbor seals will 
enter this area without detection while pile driving activities are 
underway, it is possible that harbor seals may approach and enter the 
Level A harassment zone undetected. Mr. Erickson has observed up to 
four harbor seals in the water near the existing dock. Therefore, Mr. 
Erickson estimates that up to four harbor seals may approach the site 
within 70 m of the source each day. Impact pile driving is expected to 
occur on up to four days (Table 1). For this reason, Mr. Erickson has 
requested take of 16 harbor seals by Level A harassment.

Harbor Porpoise

    Although there have been no systematic studies or observations of 
harbor porpoises specific to Auke Bay, there is the potential for them 
to occur within the project area. Abundance data for harbor porpoises 
in southeast Alaska were collected during 18 seasonal surveys spanning 
22 years, from 1991 to 2012. During that study, a total of 398 harbor 
porpoises were observed in the northern inland waters of southeast 
Alaska, including Lynn Canal (Dahlheim et al., 2015). Mean group size 
of harbor porpoises in southeast Alaska varies by season. In the fall, 
mean group size was determined to be 1.88 harbor porpoises (Dahlheim et 
al., 2009). However, groups of five to six harbor porpoises have been 
observed in Auke Bay (B. Lambert, pers. comm.). Therefore, Mr. Erickson 
estimates that up to six harbor porpoises may enter the Level B 
harassment zone on each of the eight days of pile driving, for a total 
of 48 exposures.
    The largest Level A harassment zone extends 156.1 m from the source 
(Table 8). Mr. Erickson is planning to implement shutdown zones that 
encompass the Level A harassment zones (see Proposed Mitigation 
section). However, harbor porpoises are known to be an inconspicuous 
species and are challenging for protected species observers (PSOs) to 
sight, making any approach to a specific area potentially difficult to 
detect. Because harbor porpoises move quickly and elusively, it is 
possible that they may enter the Level A harassment zone without 
detection. Mr. Erickson estimates that one pair of harbor porpoises may 
enter the Level A harassment zone on each of the four days of impact 
pile driving for a total of eight potential takes by Level A 
harassment.

Dall's Porpoise

    Dall's porpoises are not expected to occur within Auke Bay because 
the shallow water habitat of the bay is atypical of areas where Dall's 
porpoises usually occur. However, Dall's porpoises may 
opportunistically inhabit nearshore habitat. The largest group of 
Dall's porpoises observed in Auke Bay was 10 individuals in 1994. 
Therefore, Mr. Erickson estimates that one group of ten Dall's 
porpoises may enter the Level B harassment zone once during 
construction, for a total of ten exposures.
    Mr. Erickson will implement shutdown zones for porpoises that 
encompass the Level A harassment zones for each pile driving 
activities. The largest Level A harassment zone for Dall's porpoise 
extends 156.1 m from the source during impact installation of 20-in 
steel piles (Table 8). Given the larger group size and more conspicuous 
rooster-tail generated by swimming Dall's porpoises, which makes them 
more noticeable than harbor porpoises, PSOs are expected to detect 
Dall's porpoises prior to them entering the Level A harassment zone. 
Therefore, takes of Dall's porpoises by Level A harassment have not 
been requested and are not proposed to be authorized.

Killer Whale

    Killer whales are known visitors of the Lynn Canal area, and 
occasionally enter Auke Bay. Oceanus Alaska compiled sightings records 
reported by Juneau residents and reported an average of 25 killer 
whales in the area per year between 2010 and 2017. Killer whales in the 
project area may be of the Northern Resident, Alaska Resident, or West 
Coast Transient stocks. The Alaska Resident group AG pod is known to 
frequent the Juneau Area in groups of up to 25 individuals (B. Lambert, 
pers. comm.). Mr. Erickson estimates that one group of up to 25 killer 
whales may enter the Level B harassment zone during the eight days of 
pile driving for a total of 25 exposures.
    Mr. Erickson will implement shutdown zones that encompass the 
largest Level A harassment zones for killer whales during all pile 
driving activities. Killer whales are generally conspicuous and PSOs 
are expected to detect killer whales and implement a shutdown before 
the animals enter the Level A harassment zone. Therefore, takes by 
Level A harassment have not been requested and are not proposed to be 
authorized.

Humpback Whale

    Use of Auke Bay by humpback whales is intermittent and irregular 
year-round. During winter, researchers have documented 1 to 19 
individual humpback whales per month in waters close to the project 
area, including Lynn Canal (Moran et al., 2018a; Straley et al., 2018). 
Group sizes in southeast Alaska generally range from one to four 
individuals (Dahlheim et al., 2009). Mr. Erickson estimates that one 
group of up to four individuals may be present in the Level B 
harassment zone per day during the eight days of pile driving, for a 
total of 32 takes by Level B harassment.
    The largest Level A harassment zone for humpback whales extends 
131.1 m from the source during impact installation of 20-in piles 
(Table 8). Given the irregular and small presence of humpback whales in 
Auke Bay, along with the fact that PSOs are expected to detect humpback 
whales before they enter the Level A harassment zone and implement 
shutdowns to prevent take by Level A harassment, no Level A takes have 
been requested nor proposed to be authorized.

Minke Whale

    Dedicated surveys for cetaceans in southeast Alaska found that 
minke whales were scattered throughout inland waters from Glacier Bay 
and Icy Strait to Clarence Strait, with small concentrations near the 
entrance of Glacier Bay. All sightings were of single minke whales, 
except for a single sighting of multiple minke whales. Surveys took 
place in spring, summer, and fall, and minke whales were present in low 
numbers in all seasons and years (Dahlheim et al., 2009). Anecdotal 
reports have not included minke whales near Auke Bay. However, minke 
whales are distributed throughout a wide

[[Page 50402]]

variety of habitats and have been observed in nearby Glacier Bay, 
indicating they may potentially occur within the Level B harassment 
zone. Therefore, Mr. Erickson estimates that one minke whale may enter 
the Level B harassment zone once during the eight days of pile driving 
activities, for a total of one take by Level B harassment.
    The Level A harassment zones for minke whales are the same as for 
humpback whales, and the shutdown protocols will be the same as well. 
Therefore, given the low occurrence of minke whales combined with the 
mitigation, takes by Level A harassment have not been requested and are 
not proposed to be authorized.

                                     Table 9--Estimated Take by Level A and Level B Harassment, by Species and Stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                           Proposed take
                Common name                             Stock                  Stock          Level A         Level B     Total proposed   as percentage
                                                                           abundance \a\                                       take          of stock
--------------------------------------------------------------------------------------------------------------------------------------------------------
Humpback whale............................  Central North Pacific.......          10,103               0              32          \b\ 32            0.32
Minke Whale...............................  Alaska......................             N/A               0               1               1             N/A
Killer whale..............................  Alaska Resident.............           2,347               0              25              25        \d\ 1.06
                                            Northern Resident...........             261                                                        \d\ 9.58
                                            West Coast Transient........             243                                                        \d\ 10.3
Harbor porpoise...........................  Southeast Alaska............             975               8              40              48            4.92
Dall's porpoise...........................  Alaska......................          83,400               0              10              10            <0.1
Steller sea lion..........................  Western U.S.................          54,267               0             175         \c\ 175            0.32
                                            Eastern U.S.................          41,638               0             793             793            1.90
California sea lion.......................  U.S.........................         257,606               0               8               8           <0.01
Harbor seal...............................  Lynn Canal/Stephens Passage.           9,478              16             400             416            4.39
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Stock or DPS size is Nbest according to NMFS 2018 Draft Stock Assessment Reports.
\b\ For ESA section 7 consultation purposes, 6.1 percent are designated to the Mexico DPS and the remaining are designated to the Hawaii DPS; therefore,
  we assigned 2 Level B takes to the Mexico DPS.
\c\ Based on numbers reported in Hastings et al. (2019) and in consultation with the Alaska Regional Office, we used an 18.1 percent distinction factor
  to determine the number of animals potentially from the western DPS.
\d\ These percentages assume all 25 takes may occur to each individual stock, thus the percentage of one or more stocks are likely inflated as the takes
  would be divided among multiple stocks.

Proposed 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 (latter not applicable for this action). 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 and their habitat (50 CFR 
216.104(a)(11)).
    In evaluating how mitigation may or may not be appropriate to 
ensure the least practicable adverse impact on species or stocks and 
their habitat, as well as subsistence uses where applicable, we 
carefully consider two primary factors:
    (1) The manner in which, and the degree to which, the successful 
implementation of the measure(s) is expected to reduce impacts to 
marine mammals, marine mammal species or stocks, and their habitat, as 
well as subsistence uses. This considers the nature of the potential 
adverse impact being mitigated (likelihood, scope, range). It further 
considers the likelihood that the measure will be effective if 
implemented (probability of accomplishing the mitigating result if 
implemented as planned), the likelihood of effective implementation 
(probability implemented as planned); and
    (2) the practicability of the measures for applicant 
implementation, which may consider such things as cost, impact on 
operations, and, in the case of a military readiness activity, 
personnel safety, practicality of implementation, and impact on the 
effectiveness of the military readiness activity.

Mitigation for Marine Mammals and Their Habitat

    In addition to the measures described later in this section, Mr. 
Erickson will employ the following standard mitigation measures:
     Conduct briefings between construction supervisors and 
crews and the marine mammal monitoring team prior to the start of all 
pile driving activity, and when new personnel join the work, to explain 
responsibilities, communication procedures, marine mammal monitoring 
protocol, and operational procedures;
     For in-water heavy machinery work other than pile driving 
(e.g., standard barges, etc.), 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);
     Work may only occur during daylight hours, when visual 
monitoring of marine mammals can be conducted;
     For those marine mammals for which Level B harassment take 
has not been requested, in-water pile installation/removal and drilling 
will shut down immediately if such species are observed within or on a 
path towards the monitoring zone (i.e., Level B harassment zone); and
     If take reaches the authorized limit for an authorized 
species, pile installation will be stopped as these species approach 
the Level B harassment zone to avoid additional take.
    The following measures would apply to ADOT&PF's mitigation 
requirements:
    Establishment of Shutdown Zone for Level A Harassment--For all pile 
driving/removal and drilling activities, Mr. Erickson would 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

[[Page 50403]]

mammal (or in anticipation of an animal entering the defined area). 
These shutdown zones would be used to prevent incidental Level A 
exposures from impact pile driving for Steller sea lions, California 
sea lions, Dall's porpoises, killer whales, humpback whales, and minke 
whales, and to reduce the potential for such take for harbor seals and 
harbor porpoises. During all pile driving and removal activities, a 
minimum shutdown zone of 20 m would be enforced (Table 10). Shutdown 
zones for each specific activity are based on the Level A harassment 
zones and therefore vary by pile-size, type, driving method, and marine 
mammal hearing group (Table 10).

                              Table 10--Shutdown Zones for Pile Driving Activities
----------------------------------------------------------------------------------------------------------------
                                                                 Shutdown zone (m)
                                 -------------------------------------------------------------------------------
            Activity                                                                  Phocid          Otariid
                                   LF cetaceans    MF cetaceans    HF cetaceans      pinnipeds       pinnipeds
----------------------------------------------------------------------------------------------------------------
Vibratory Timber Pile Removal...              10              10              10              10              10
Vibratory Pile Driving (12.75-                10              10              10              10              10
 in)............................
Vibratory Pile Driving (20-in)..              20              10              30              15              10
Drilling........................              75              10             105              45              10
Impact Pile Driving 12.75-in....              40              10              50              20              10
Impact Pile Driving 20-in.......             135              10             160              75              10
----------------------------------------------------------------------------------------------------------------

    Establishment of Monitoring Zones for Level B Harassment--Mr. 
Erickson would establish monitoring zones to correlate with Level B 
disturbance zones or zones of influence which are areas where SPLs are 
equal to or exceed the 160 dB rms threshold for impact driving and the 
120 dB rms threshold during vibratory driving and drilling. Monitoring 
zones provide utility for observing by establishing monitoring 
protocols for areas adjacent to the shutdown zones. Monitoring zones 
enable observers to be aware of and communicate the presence of marine 
mammals in the project area outside the shutdown zone and thus prepare 
for a potential cease of activity should the animal enter the shutdown 
zone. The proposed monitoring zones are described in Table 11. Should 
PSOs determine the monitoring zone cannot be effectively observed in 
its entirety, Level B harassment exposures will be recorded and 
extrapolated based upon the number of observed take and the percentage 
of the Level B zone that was not visible.

                Table 11--Marine Mammal Monitoring Zones
------------------------------------------------------------------------
                                                            Monitoring
                        Activity                             zone (m)
------------------------------------------------------------------------
Impact installation of 12.75-in piles...................             135
Impact installation of 20-in piles......................           1,000
Vibratory timber pile removal...........................           1,360
Vibratory installation of 21.75-in piles................           2,155
Vibratory installation of 20-in piles...................           5,410
Drilling................................................          12,100
------------------------------------------------------------------------

    Soft Start--The use of soft-start procedures are 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 
would be required to provide an initial set of strikes from the hammer 
at reduced energy, with each strike followed by a 30-second waiting 
period. This procedure would be conducted a total of three times before 
impact pile driving begins. Soft start would be implemented at the 
start of each day's impact pile driving and at any time following 
cessation of impact pile driving for a period of thirty minutes or 
longer. Soft start is not required during vibratory pile driving and 
removal activities.
    Pre-Activity Monitoring--Prior to the start of daily in-water 
construction activity, or whenever a break in pile driving/removal or 
drilling of 30 minutes or longer occurs, PSOs will observe the shutdown 
and monitoring zones for a period of 30 minutes. The shutdown zone will 
be cleared when a marine mammal has not been observed within the zone 
for that 30-minute period. If a marine mammal is observed within the 
shutdown zone, a soft-start cannot proceed until the animal has left 
the zone or has not been observed for 15 minutes. If the Level B 
harassment zone has been observed for 30 minutes and non-permitted 
species are not present within the zone, soft start procedures can 
commence and work can continue even if visibility becomes impaired 
within the Level B monitoring zone. If a marine mammal permitted for 
Level B take is present in the Level B harassment zone, activities may 
begin and Level B take will be recorded. As stated above, if the entire 
Level B zone is not visible at the start of construction, piling or 
drilling activities can begin. If work ceases for more than 30 minutes, 
the pre-activity monitoring of both the Level B and shutdown zone will 
commence.
    Based on our evaluation of the applicant's proposed measures, NMFS 
has preliminarily determined that the proposed mitigation measures 
provide the means effecting the least practicable impact on the 
affected species or stocks and their habitat, paying particular 
attention to rookeries, mating grounds, and areas of similar 
significance.

Proposed 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 
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 mammals that are expected to be present in the 
proposed action area. Effective reporting is critical both to 
compliance as well as ensuring that the most value is obtained from the 
required monitoring.
    Monitoring and reporting requirements prescribed by NMFS should 
contribute to improved understanding of one or more of the following:
     Occurrence of marine mammal species or stocks in the area 
in which take is anticipated (e.g., presence, abundance, distribution, 
density);
     Nature, scope, or context of likely marine mammal exposure 
to potential

[[Page 50404]]

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 marine mammal responses (behavioral or 
physiological) to acoustic stressors (acute, chronic, or cumulative), 
other stressors, or cumulative impacts from multiple stressors;
     How anticipated responses to stressors impact either: (1) 
Long-term fitness and survival of individual marine mammals; or (2) 
populations, species, or stocks;
     Effects on marine mammal habitat (e.g., marine mammal prey 
species, acoustic habitat, or other important physical components of 
marine mammal habitat); and
     Mitigation and monitoring effectiveness.

Marine Mammal Visual Monitoring

    Monitoring shall be conducted by NMFS-approved observers. Trained 
observers shall be placed from the best vantage point(s) practicable to 
monitor for marine mammals and implement shutdown or delay procedures 
when applicable through communication with the equipment operator. 
Observer training must be provided prior to project start, and shall 
include instruction on species identification (sufficient to 
distinguish the species in the project area), description and 
categorization of observed behaviors and interpretation of behaviors 
that may be construed as being reactions to the specified activity, 
proper completion of data forms, and other basic components of 
biological monitoring, including tracking of observed animals or groups 
of animals such that repeat sound exposures may be attributed to 
individuals (to the extent possible).
    Monitoring would be conducted 30 minutes before, during, and 30 
minutes after pile driving/removal and drilling activities. In 
addition, observers shall record all incidents of marine mammal 
occurrence, regardless of distance from activity, and shall document 
any behavioral reactions in concert with distance from piles being 
driven or removed. Pile driving/removal and drilling activities include 
the time to install or remove a single pile or series of piles, as long 
as the time elapsed between uses of the pile driving equipment is no 
more than 30 minutes.
    At least two PSOs will be on duty during all pile driving 
activities. One PSO will be stationed at the dock site to allow full 
monitoring of the waters within the shutdown zones and the closest 
waters of the Level B harassment monitoring zones. An additional PSO 
will be positioned in a vessel in Auke Bay to observed the larger 
monitoring zones. Most of the shoreline of Auke Bay is privately owned 
and unavailable for PSOs to access. Additionally, PSOs cannot be 
stationed on the shore of the various islands in Auke Bay due to safety 
concerns. Therefore, a vessel-based PSO is the most practicable 
position for this project. Potential PSO locations are shown in Figure 
2 in Mr. Erickson's Marine Mammal Monitoring Plan.
    PSOs would scan the waters using binoculars, and/or spotting 
scopes, and would use a handheld GPS or range-finder device to verify 
the distance to each sighting from the project site. All PSOs would be 
trained in marine mammal identification and behaviors and are required 
to have no other project-related tasks while conducting monitoring. In 
addition, monitoring will be conducted by qualified observers, who will 
be placed at the best vantage point(s) practicable to monitor for 
marine mammals and implement shutdown/delay procedures when applicable 
by calling for the shutdown to the hammer operator. Mr. Erickson would 
adhere to the following observer qualifications:
    (i) Independent observers (i.e., not construction personnel) are 
required;
    (ii) At least one observer must have prior experience working as an 
observer;
    (iii) Other observers may substitute education (degree in 
biological science or related field) or training for experience; and
    (iv) Mr. Erickson must submit observer CVs for approval by NMFS.
    Additional standard observer qualifications include:
     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; and
     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.
    A draft marine mammal monitoring report would be submitted to NMFS 
within 90 days after the completion of pile driving and removal and 
drilling activities. It will include an overall description of work 
completed, a narrative regarding marine mammal sightings, and 
associated PSO data sheets. Specifically, the report must include:
     Date and time that monitored activity begins or ends;
     Construction activities occurring during each observation 
period;
     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 observed;
     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;
     Other human activity in the area; and
     A summary of the total number of individuals of each 
species detected within the Level B Harassment Zone, and estimated as 
taken if correction factor appropriate, and the total number of 
individuals of each species detected within the Level A Harassment Zone 
and the average amount of time that they remained in that zone.
    If no comments are received from NMFS within 30 days, the draft 
final report will constitute the final report. If comments are 
received, a final report addressing NMFS comments must be submitted 
within 30 days after receipt of comments.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner prohibited by the IHA 
(if issued), such as an injury, serious injury or mortality, Mr. 
Erickson would immediately cease the specified activities and report 
the incident to the Chief of the Permits and Conservation Division, 
Office of

[[Page 50405]]

Protected Resources, NMFS, and the Alaska Regional Stranding 
Coordinator. The report would include the following information:
     Description of the incident;
     Environmental conditions (e.g., Beaufort sea state, 
visibility);
     Description of all marine mammal observations in the 24 
hours preceding the incident;
     Species identification or description of the animal(s) 
involved;
     Fate of the animal(s); and
     Photographs or video footage of the animal(s) (if 
equipment is available).
    Activities would not resume until NMFS is able to review the 
circumstances of the prohibited take. NMFS would work with Mr. Erickson 
to determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. Mr. Erickson would not be 
able to resume pile driving activities until notified by NMFS via 
letter, email, or telephone.
    In the event that Mr. Erickson discovers an injured or dead marine 
mammal, and the lead PSO determines that the cause of the injury or 
death is unknown and the death is relatively recent (e.g., in less than 
a moderate state of decomposition as described in the next paragraph), 
Mr. Erickson would immediately report the incident to the Chief of the 
Permits and Conservation Division, Office of Protected Resources, NMFS, 
and the NMFS Alaska Stranding Hotline and/or by email to the Alaska 
Regional Stranding Coordinator. The report would include the same 
information identified in the paragraph above. Activities would be able 
to continue while NMFS reviews the circumstances of the incident. NMFS 
would work with Mr. Erickson to determine whether modifications in the 
activities are appropriate.
    In the event that Mr. Erickson discovers an injured or dead marine 
mammal and the lead PSO determines that the injury or death is not 
associated with or related to the activities authorized in the IHA 
(e.g., previously wounded animal, carcass with moderate to advanced 
decomposition, or scavenger damage), Mr. Erickson would report the 
incident to the Chief of the Permits and Conservation Division, Office 
of Protected Resources, NMFS, and the NMFS Alaska Stranding Hotline 
and/or by email to the Alaska Regional Stranding Coordinator, within 24 
hours of the discovery. Mr. Erickson would provide photographs, video 
footage (if available), or other documentation of the stranded animal 
sighting to NMFS and the Marine Mammal Stranding Network.

Negligible Impact Analysis and Determination

    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 estimates of the 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), as well as effects on habitat, and the likely effectiveness 
of the mitigation. We also assess the number, intensity, and context of 
estimated takes by evaluating this information relative to population 
status. 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 this 
analysis 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).
    Pile driving/removal and drilling activities associated with the 
project as outlined previously, have the potential to disturb or 
displace marine mammals. Specifically, the specified activities may 
result in take, in the form of Level A harassment and Level B 
harassment from underwater sounds generated from pile driving and 
removal. Potential takes could occur if individuals of these species 
are present in zones ensonified above the thresholds for Leval A or 
Level B harassment identified above when these activities are underway.
    The takes from Level A and Level B harassment would be due to 
potential behavioral disturbance, TTS, and PTS. No mortality is 
anticipated given the nature of the activity and measures designed to 
minimize the possibility of injury to marine mammals. Level A 
harassment is only anticipated for harbor porpoise and harbor seal. The 
potential for harassment is minimized through the construction method 
and the implementation of the planned mitigation measures (see Proposed 
Mitigation section).
    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; HDR, Inc. 2012; Lerma 2014; ABR 2016). Most likely for pile 
driving, individuals will simply move away from the sound source and be 
temporarily displaced from the areas of pile driving and drilling, 
although even this reaction has been observed primarily only in 
association with impact pile driving. The pile driving activities 
analyzed here are similar to, or less impactful than, numerous other 
construction activities conducted in southeast Alaska, which have taken 
place with no known long-term adverse consequences from behavioral 
harassment. Level B harassment will be reduced to the level of least 
practicable adverse impact through use of mitigation measures described 
herein and, if sound produced by project activities is sufficiently 
disturbing, animals are likely to simply avoid the area while the 
activity is occurring. While vibratory driving and drilling associated 
with the proposed project may produce sound at distances of many 
kilometers from the project site, thus intruding on some habitat, the 
project site itself is located in a busy harbor and the majority of 
sound fields produced by the specified activities are close to the 
harbor. Therefore, we expect that animals annoyed by project sound 
would simply avoid the area and use more-preferred habitats.
    In addition to the expected effects resulting from authorized Level 
B harassment, we anticipate that harbor porpoises and harbor seals may 
sustain some limited Level A harassment in the form of auditory injury. 
However, given the relatively small size of the Level A harassment 
zones and the anticipated effectiveness of mitigation, animals in these 
locations that experience PTS would likely only receive slight PTS, 
i.e., minor degradation of hearing capabilities within regions of 
hearing that align most completely with the energy produced by pile 
driving, i.e., the low-frequency region below 2 kHz, not severe hearing 
impairment or impairment in the regions of greatest hearing 
sensitivity. If hearing impairment occurs, it is most likely that the 
affected animal would lose a few decibels in its hearing sensitivity, 
which in most cases is not likely to meaningfully affect its ability to 
forage

[[Page 50406]]

and communicate with conspecifics. As described above, we expect that 
marine mammals would be likely to move away from a sound source that 
represents an aversive stimulus, especially at levels that would be 
expected to result in PTS, given sufficient notice through use of soft 
start.
    Nearly all inland waters of southeast Alaska, including Auke Bay, 
are included in the southeast Alaska humpback whale feeding BIA 
(Ferguson et al., 2015), though humpback whale distribution in 
southeast Alaska varies by season and waterway (Dahlheim et al. 2009). 
Humpback whales are present within Auke Bay intermittently and in low 
numbers. The area of the BIA that may be affected by the proposed 
project is small relative to the overall area of the BIA, and the area 
of suitable humpback whale habitat that is not included in the BIA. The 
southeast Alaska humpback whale feeding BIA is active between March and 
November. While the exact timing of the proposed project is unknown, 
Mr. Erickson's pile driving activities are expected to take only eight 
days. If the project were to occur between March and November, the days 
of activity represent a small fraction of the time the BIA is active 
and, thus, even if humpback whale feeding behaviors were interrupted by 
the activity, the disturbance would be short-term and alternative 
habitat and foraging opportunities are available nearby. Further, only 
a very small portion of the humpback stock is expected to enter the 
area and potentially be disturbed. Therefore, any adverse effects on 
humpback whales resulting from disturbances occurring in the southeast 
Alaska humpback whale feeding BIA are expected to be short-term and 
minor and not adversely impact reproduction or survival, much less the 
stock.
    The project also is not expected to have significant adverse 
effects on affected marine mammals' habitat. The project activities 
would not modify existing marine mammal habitat for a significant 
amount of time. The activities may cause some fish to leave the area of 
disturbance, thus temporarily impacting marine mammals' foraging 
opportunities in a limited portion of the foraging range; but, because 
of the short duration of the activities and the relatively small area 
of the habitat that may be affected, the impacts to marine mammal 
habitat are not expected to cause significant or long-term negative 
consequences.
    In summary and as described above, the following factors primarily 
support our preliminary determination that the impacts resulting from 
this activity are not expected to adversely affect the species or stock 
through effects on annual rates of recruitment or survival:
     No mortality is anticipated or authorized;
     The Level A harassment exposures are anticipated to result 
only in slight PTS, within the lower frequencies associated with pile 
driving;
     The anticipated incidents of Level B harassment would 
consist of, at worst, temporary modifications in behavior that would 
not result in fitness impacts to individuals;
     The area impacted by the specified activity is very small 
relative to the overall habitat ranges of all species, does not include 
ESA-designated critical habitat, and only temporally overlaps with the 
southeast Alaska humpback whale feeding BIA for two months of the 
planned six months of activity; and
     The proposed mitigation measures are expected to reduce 
the effects of the specified activity to the level of least practicable 
adverse impact.
    In addition, although affected humpback whales and Steller sea 
lions may be from a DPS that is listed under the ESA, it is unlikely 
that minor noise effects in a small, localized area of habitat would 
have any effect on the stocks' ability to recover. 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 activities will have only minor, short-term effects on 
individuals. The specified activities are 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 proposed monitoring and 
mitigation measures, NMFS preliminarily finds that the total marine 
mammal take from the proposed activity will have a negligible impact on 
all affected marine mammal species or stocks.

Small Numbers

    As noted above, only small numbers of incidental take may be 
authorized under Sections 101(a)(5)(A) and (D) of the MMPA for 
specified activities other than military readiness activities. The MMPA 
does not define small numbers and so, in practice, where estimated 
numbers are available, NMFS compares the number of individuals taken to 
the most appropriate estimation of abundance of the relevant species or 
stock in our determination of whether an authorization is limited to 
small numbers of marine mammals. Additionally, other qualitative 
factors may be considered in the analysis, such as the temporal or 
spatial scale of the activities.
    Table 8 indicates the number of animals that could be exposed to 
received noise levels that could cause Level A and Level B harassment 
for the proposed work in Auke Bay. Our analysis shows that less than 11 
percent of each affected stock could be taken by harassment. The 
numbers of animals proposed to be taken for these stocks would be 
considered small relative to the relevant stock's abundances even if 
each estimated taking occurred to a new individual--an extremely 
unlikely scenario.
    Based on the analysis contained herein of the proposed activity 
(including the proposed mitigation and monitoring measures) and the 
anticipated take of marine mammals, NMFS preliminarily finds that small 
numbers of marine mammals will be taken relative to the population size 
of the affected species or stocks.

Unmitigable Adverse Impact Analysis and Determination

    In order to issue an IHA, NMFS must find that the specified 
activity will not have an ``unmitigable adverse impact'' on the 
subsistence uses of the affected marine mammal species or stocks by 
Alaskan Natives. NMFS has defined ``unmitigable adverse impact'' in 50 
CFR 216.103 as an impact resulting from the specified activity: (1) 
That is likely to reduce the availability of the species to a level 
insufficient for a harvest to meet subsistence needs by: (i) Causing 
the marine mammals to abandon or avoid hunting areas; (ii) Directly 
displacing subsistence users; or (iii) Placing physical barriers 
between the marine mammals and the subsistence hunters; and (2) That 
cannot be sufficiently mitigated by other measures to increase the 
availability of marine mammals to allow subsistence needs to be met.
    The proposed project is not known to occur in an important 
subsistence hunting area. Auke Bay is a developed area with regular 
marine vessel traffic. Of the marine mammals considered in this IHA 
application, only harbor seals are known to be used for subsistence in 
the project area. In a previous consultation with ADF&G, the Douglas 
Indian Association, Sealaska Heritage Institute, and the Central 
Council of the Tlingit and Haida Indian Tribes of Alaska, 
representatives indicated that the primary concern with construction 
activities in Statter Harbor was impacts to herring fisheries, not 
marine

[[Page 50407]]

mammals. As stated above, impacts to fish from the proposed project are 
expected to be localized and temporary, so are not likely to impact 
herring fisheries. If any tribes express concerns regarding project 
impacts to subsistence hunting of marine mammals, further communication 
between will take place, including provision of any project 
information, and clarification of any mitigation and minimization 
measures that may reduce potential impacts to marine mammals.
    Based on the description of the specified activity, the measures 
described to minimize adverse effects on the availability of marine 
mammals for subsistence purposes, and the proposed mitigation and 
monitoring measures, NMFS has preliminarily determined that there will 
not be an unmitigable adverse impact on subsistence uses from [name of 
applicant]'s proposed activities.

Endangered Species Act (ESA)

    Section 7(a)(2) of the Endangered Species Act of 1973 (ESA: 16 
U.S.C. 1531 et seq.) requires that each Federal agency insure that any 
action it authorizes, funds, or carries out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the destruction or adverse modification of designated 
critical habitat. To ensure ESA compliance for the issuance of IHAs, 
NMFS consults internally, in this case with the Alaska Regional Office, 
whenever we propose to authorize take for endangered or threatened 
species.
    NMFS is proposing to authorize take of wDPS Steller sea lions and 
Mexico DPS humpback whales, which are listed under the ESA. The Permits 
and Conservation Division has requested initiation of section 7 
consultation with NMFS' Alaska Regional Office for the issuance of this 
IHA. NMFS will conclude the ESA consultation prior to reaching a 
determination regarding the proposed issuance of the authorization.

Proposed Authorization

    As a result of these preliminary determinations, NMFS proposes to 
issue an IHA to Mr. Erickson for conducting pile installation and 
removal activities between January and December 2020, provided the 
previously mentioned mitigation, monitoring, and reporting requirements 
are incorporated. A draft of the proposed IHA can be found at https://www.fisheries.noaa.gov/permit/incidental-take-authorizations-under-marine-mammal-protection-act.

Request for Public Comments

    We request comment on our analyses, the proposed authorization, and 
any other aspect of this Notice of Proposed IHA for the proposed 
action. We also request at this time comment on the potential renewal 
of this proposed IHA as described in the paragraph below. Please 
include with your comments any supporting data or literature citations 
to help inform decisions on the request for this IHA or a subsequent 
Renewal.
    On a case-by-case basis, NMFS may issue a one-year IHA renewal with 
an additional 15 days for public comments when (1) another year of 
identical or nearly identical activities as described in the Specified 
Activities section of this notice is planned or (2) the activities as 
described in the Specified Activities section of this notice would not 
be completed by the time the IHA expires and a Renewal would allow for 
completion of the activities beyond that described in the Dates and 
Duration section of this notice, provided all of the following 
conditions are met:
     A request for renewal is received no later than 60 days 
prior to expiration of the current IHA.
     The request for renewal must include the following:
    (1) An explanation that the activities to be conducted under the 
requested Renewal are identical to the activities analyzed under the 
initial IHA, are a subset of the activities, or include changes so 
minor (e.g., reduction in pile size) that the changes do not affect the 
previous analyses, mitigation and monitoring requirements, or take 
estimates (with the exception of reducing the type or amount of take 
because only a subset of the initially analyzed activities remain to be 
completed under the Renewal).
    (2) A preliminary monitoring report showing the results of the 
required monitoring to date and an explanation showing that the 
monitoring results do not indicate impacts of a scale or nature not 
previously analyzed or authorized.
     Upon review of the request for Renewal, the status of the 
affected species or stocks, and any other pertinent information, NMFS 
determines that there are no more than minor changes in the activities, 
the mitigation and monitoring measures will remain the same and 
appropriate, and the findings in the initial IHA remain valid.

    Dated: September 19, 2019.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2019-20777 Filed 9-24-19; 8:45 am]
 BILLING CODE 3510-22-P