[Federal Register Volume 86, Number 132 (Wednesday, July 14, 2021)]
[Notices]
[Pages 37124-37133]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-14980]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

[RTID 0648-XB208]


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Army Corps of Engineers Debris Dock 
Replacement Project, Sausalito, California

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

ACTION: Notice; issuance of an incidental harassment authorization.

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SUMMARY: In accordance with the regulations implementing the Marine 
Mammal Protection Act (MMPA) as amended, notification is hereby given 
that NMFS has issued an incidental harassment authorization (IHA) to 
the U.S. Army Corps of Engineers (ACOE) to incidentally harass, by 
Level A and Level B harassment only, marine mammals during construction 
activities associated with the Debris Dock Replacement Project in 
Sausalito, California.

DATES: This authorization is effective from September 1, 2021 through 
August 31, 2022.

FOR FURTHER INFORMATION CONTACT: Dwayne Meadows, Ph.D., 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 
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 the 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 the takings are set forth.
    The definitions of all applicable MMPA statutory terms cited above 
are included in the relevant sections below.

Summary of Request

    On March 17, 2021, NMFS received an application from ACOE 
requesting an IHA to take small numbers of seven species of marine 
mammals incidental to pile driving associated with the Debris Dock 
Replacement Project. The application was deemed adequate and complete 
on May 20, 2021. The ACOE's request is for take of a small number of 
these species by Level A or Level B harassment. Neither the ACOE nor 
NMFS expects serious injury or mortality to result from this activity 
and, therefore, an IHA is appropriate.

Description of the Specified Activity

Overview

    The purpose of the project is to replace the existing decaying dock 
and other onshore infrastructure used to move marine debris collected 
from San Francisco Bay onto land for disposal. The existing dock will 
be removed and replaced. The work will involve impact hammering 31 24-
inch diameter concrete deck support piles and 17 14-inch diameter 
timber fender piles for the replacement dock and removal of the decayed 
dock by cutting or otherwise removing 31 18-inch diameter concrete deck 
support piles and 17 14-inch diameter timber fender piles. The ACOE 
recently informed us that three of the 24-inch diameter concrete piles 
may be replaced with 18-inch diameter concrete piles, but we analyzed 
the more conservative case of all 24-inch diameter concrete piles. This 
construction work will take no more than 26 days of in-water pile work. 
A detailed description of the planned project is provided in the 
Federal Register notice for the proposed IHA (86 FR 28768; May 28, 
2021). Since that time, no changes have been made to the planned 
activities. Therefore, a detailed description is not provided here. 
Please refer to that Federal Register notice for the description of the 
specific activity.
    The pile driving/removal can result in take of marine mammals from 
sound in the water which results in behavioral harassment or auditory 
injury.
    In summary, the project period includes 10 days of pile removal and 
16 days of pile installation activities for which incidental take 
authorization is requested.

                             Table 1--Summary of Pile Driving and Removal Activities
----------------------------------------------------------------------------------------------------------------
                                                    Number of    Minutes/strikes                     Duration
            Method                 Pile type          piles          per pile      Piles per day      (days)
----------------------------------------------------------------------------------------------------------------
Cutting......................  18-inch concrete              31  5 min..........              10               7
Cutting......................  14-inch timber..              17  5 min..........              10               3
Impact Driving...............  24-inch concrete              31  1,000 strikes..              10              10

[[Page 37125]]

 
Impact Driving...............  14-inch timber..              17  1,000 strikes..              10               6
                                                ----------------------------------------------------------------
    Totals...................  ................              96  ...............  ..............              26
----------------------------------------------------------------------------------------------------------------

    Mitigation, monitoring, and reporting measures are described in 
detail later in this document (please see Mitigation and Monitoring and 
Reporting).

Comments and Responses

    A notice of NMFS's proposal to issue an IHA to the ACOE was 
published in the Federal Register on May 28, 2021 (86 FR 28768). That 
notice described, in detail, the ACOE's activity, the marine mammal 
species that may be affected by the activity, and the anticipated 
effects on marine mammals. During the 30-day public comment period, 
NMFS received public comment from one commenter. The U.S. Geological 
Survey noted they have ``no comment at this time''.

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 
the project area in San Francisco Bay and summarizes information 
related to the population or stock, including regulatory status under 
the MMPA and Endangered Species Act (ESA) and potential biological 
removal (PBR), where known. For taxonomy, we follow Committee on 
Taxonomy (2020). 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. Pacific SARs and draft SARs (e.g., Caretta et al., 2020a 
and b).

                    Table 2--Species That Spatially Co-Occur With the Activity to the Degree That Take Is Reasonably Likely To Occur
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                                                                                         ESA/MMPA status;    Stock abundance (CV,
             Common name                  Scientific name               Stock             strategic (Y/N)      Nmin, most recent       PBR     Annual M/
                                                                                                \1\          abundance survey) \2\               SI \3\
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                                          Order Cetartiodactyla--Cetacea--Superfamily Mysticeti (baleen whales)
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Family Eschrichtiidae:
    Gray Whale......................  Eschrichtius robustus..  Eastern North Pacific..  -, -, N             26,960 (0.05, 25,849,         801        138
                                                                                                             2016).
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                            Order Cetartiodactyla--Cetacea--Superfamily Odontoceti (toothed whales, dolphins, and porpoises)
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Family Delphinidae:
    Bottlenose Dolphin..............  Tursiops truncatus.....  California Coastal.....  -, -, N             453 (0.06, 346, 2011).        2.7       >2.0
Family Phocoenidae (porpoises):
    Harbor porpoise.................  Phocoena phocoena......  San Francisco/Russian    -, -, N             9,886 (0.51, 2019)....         66          0
                                                                River.
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                                                         Order Carnivora--Superfamily Pinnipedia
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Family Otariidae (eared seals and
 sea lions):
    California Sea Lion.............  Zalophus californianus.  United States..........  -, -, N             257,606 (N/A, 233,515,     14,011       >321
                                                                                                             2014).
    Northern fur seal...............  Callorhinus ursinus....  California.............  -, D, N             14,050 (N/A, 7,524,           451        1.8
                                                                                                             2013).
                                                               Eastern North Pacific..  -, D, N             620,660 (0.2, 525,333,     11,295        399
                                                                                                             2016).
Family Phocidae (earless seals):
    Northern elephant seal..........  Mirounga angustirostris  California Breeding....  -, -, N             179,000 (N/A, 81,368,       4,882        8.8
                                                                                                             2010).

[[Page 37126]]

 
    Harbor seal.....................  Phoca vitulina.........  California.............  -, -, N             30,968 (N/A, 27,348,        1,641         43
                                                                                                             2012).
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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: https://www.fisheries.noaa.gov/national/marine-mammal-protection/marine-mammal-stock-assessment-reports. CV is coefficient of variation; Nmin is the minimum estimate of stock abundance.
\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 Mortality/Serious Injury (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.

    Harbor seal, California sea lion, bottlenose dolphin and Harbor 
porpoise spatially co-occur with the activity to the degree that take 
is reasonably likely to occur, and we have proposed authorizing take of 
these species. For gray whale, northern fur seal and northern elephant 
seal, occurrence is such that take is possible, and we have proposed 
authorizing take of these species also.
    A detailed description of the of the species likely to be affected 
by the project, including brief introductions to the species and 
relevant stocks as well as available information regarding population 
trends and threats, and information regarding local occurrence, were 
provided in the Federal Register notice for the proposed IHA (86 FR 
28768; May 28, 2021); since that time, we are not aware of any changes 
in the status of these species and stocks; therefore, detailed 
descriptions are not provided here. Please refer to that Federal 
Register notice for these descriptions. Please also refer to NMFS' 
website (https://www.fisheries.noaa.gov/find-species) for generalized 
species accounts.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of underwater noise from the ACOE's construction 
activities have the potential to result in behavioral harassment of 
marine mammals in the vicinity of the survey area. The notice of 
proposed IHA (86 FR 28768; May 28, 2021) included a discussion of the 
effects of anthropogenic noise on marine mammals and the potential 
effects of underwater noise from the ACOE's construction on marine 
mammals and their habitat. That information and analysis is 
incorporated by reference into this final IHA determination and is not 
repeated here; please refer to the notice of proposed IHA (86 FR 28768; 
May 28, 2021).

Estimated Take

    This section provides an estimate of the number of incidental takes 
authorized 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 acoustic source (i.e., vibratory or impact pile driving) has the 
potential to result in disruption of behavioral patterns for individual 
marine mammals. There is also some potential for auditory injury (Level 
A harassment) to result for pinnipeds and harbor porpoise because 
predicted auditory injury zones are larger. The mitigation and 
monitoring measures are expected to minimize the severity of the taking 
to the extent practicable.
    As described previously, no mortality is anticipated or authorized 
for this activity. Below we describe how the take is estimated.
    Generally speaking, we estimate take by considering: (1) Acoustic 
thresholds above which 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). Due to the lack of 
marine mammal density, NMFS relied on local occurrence data and group 
size to estimate take for some species. Below, we describe the factors 
considered here in more detail and present the proposed take estimate.

Acoustic Thresholds

    NMFS recommends the use of 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

[[Page 37127]]

received levels of 120 dB re 1 microPascal ([mu]Pa) (root mean square 
(rms)) for continuous (e.g., vibratory pile-driving) and above 160 dB 
re 1 [mu]Pa (rms) for non-explosive impulsive (e.g., impact pile 
driving) or intermittent (e.g., scientific sonar) sources.
    The ACOE's proposed activity includes the use of continuous 
(underwater chainsaw and pile clippers) 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). The ACOE's activity includes the use of 
impulsive (impact pile-driving) and non-impulsive (pile cutting 
methods) sources.
    These thresholds are provided in Table 3. 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 3--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.
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* 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 [mu]Pa, and cumulative sound exposure level (LE) has
  a reference value of 1[mu]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, pile 
clippers and underwater chainsaws).
    In order to calculate distances to the Level A harassment and Level 
B harassment sound thresholds for the methods and piles being used in 
this project, NMFS used acoustic monitoring data from other locations 
to develop source levels for the various pile types, sizes and methods 
(see Table 4). Data for the pile clippers and underwater chainsaws come 
from data gathered at U.S. Navy projects in San Diego Bay (NAVFAC SW, 
2020), the source levels used are from the averages of the maximum 
source levels measured, a somewhat more conservative measure than the 
median sound levels we typically use. The source level for an 
underwater chainsaw is 150 db RMS and the source level for a large pile 
clipper is 161 dB RMS (NAVFAC SW, 2020). Because the ACOE's as yet 
unhired contractor has not decided which of the various pile removal 
methods it will use, we only use a worst-case scenario of operation 
using the loudest sound producing method (large pile clippers) to 
consider the largest possible harassment zones and estimated take.

                                      Table 4--Project Sound Source Levels
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               Method                       Pile type         Estimated noise level             Source
----------------------------------------------------------------------------------------------------------------
Cutting............................  18-inch concrete......  161 dB RMS............  NAVFAC SW 2020.
Cutting............................  14-inch timber........  161 dB RMS............  NAVFAC SW 2020.
Impact Driving.....................  24-inch concrete......  159 dB SEL; 184 dB      Illingworth and Rodkin,
                                                              Peak.                   Inc., 2019.
Impact Driving.....................  14-inch timber........  155 dB SEL; 175 dB      Table I.2-3 (CalTrans
                                                              Peak.                   2015).
----------------------------------------------------------------------------------------------------------------
Note: SEL = single strike sound exposure level; dB Peak = peak sound level; RMS = root mean square. Impact
  driving source levels reduced by 5 dB to account for use of bubble curtain.

Level B Harassment Zones

    Transmission loss (TL) is the decrease in acoustic intensity as an 
acoustic pressure wave propagates out from a source. TL parameters vary 
with frequency, temperature, sea conditions, current, source and 
receiver depth, water depth, water chemistry, and bottom composition 
and topography. The general formula for underwater TL is:
TL = B * Log10 (R1/R2)


[[Page 37128]]


where:

TL = transmission loss in dB
B = transmission loss coefficient; for practical spreading equals 15
R1 = the distance of the modeled SPL from the driven pile, and
R2 = the distance from the driven pile of the initial measurement

    The recommended TL coefficient for most nearshore environments is 
the practical spreading value of 15. This value results in an expected 
propagation environment that would lie between spherical and 
cylindrical spreading loss conditions, which is the most appropriate 
assumption for the ACOE's proposed activity in the absence of specific 
modelling.
    The ACOE determined underwater noise would fall below the 
behavioral effects threshold of 160 dB RMS for impact driving at 22 m 
and the 120 dB rms threshold for pile cutting at 5,412 m. It should be 
noted that based on the bathymetry and geography of San Francisco Bay, 
sound will not reach the full distance of the Level B harassment 
isopleths in all directions.

Level A Harassment Zones

    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 take by Level A harassment. 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 
impact pile driving or removal using any of the methods discussed 
above, NMFS 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. We used the User Spreadsheet to 
determine the Level A harassment isopleths. Inputs used in the User 
Spreadsheet or models are reported in Table 1 and the resulting 
isopleths are reported in Table 5 for each of the construction methods 
and pile types.

                                      Table 5--Level A and Level B Isopleths (meters) for Each Pile Type and Method
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                               High-
              Method                      Pile type       Low- frequency  Mid- frequency     frequency        Phocids        Otariids         Level B
                                                             cetaceans       cetaceans       cetaceans
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cutting...........................  18-inch concrete....               6             0.5             8.9             3.7             0.3            5412
Cutting...........................  14-inch timber......               6             0.5             8.9             3.7             0.3            5412
Impact Driving....................  24-inch concrete....           116.4             4.1           138.7            62.3             4.5              22
Impact Driving....................  14-inch timber......              63             2.2            75.1            33.7             2.5              22
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 that will inform the take 
calculations. Here we describe how the information provided above is 
brought together to produce a quantitative take estimate.

Bottlenose Dolphin

    Density data for this species in the project vicinity do not exist. 
San Francisco Oakland Bay Bridge (SFOBB) project monitoring showed two 
observations of this species over 6 days of monitoring in 2017 
(CalTrans 2018). One common bottlenose dolphin is sighted with 
regularity near Alameda (GGCR 2016). Based on the regularity of the 
sighting in Alameda and the SFOBB observations of approximately 0.33 
dolphin a day, we authorize the Level B harassment take equivalent to 
0.33 dolphins per day for the 26 proposed days of the project, or 9 
common bottlenose dolphin (Table 6). Because the Level A harassment 
zones are relatively small and we believe the Protected Species 
Observer (PSO) will be able to effectively monitor the Level A 
harassment zones, we do not authorize take by Level A harassment of 
bottlenose dolphins.

Harbor Porpoise

    Density data for this species from SFOBB monitoring was 0.17/km\2\ 
(CalTrans 2018). Based on the different pile types and methods there 
are three different sized ensonified areas to be considered to estimate 
Level B harassment take (Table 8). Multiplication of the above density 
times the corresponding ensonified area and duration, summing the 
results for the three methods, and subtracting the overlap of Level A 
take (below) to avoid double-counting of take, leads to authorized 
Level B harassment take of 21 harbor porpoise (Table 6).
    Similarly, calculating expected Level A harassment take as density 
times the corresponding Level A harassment ensonified area and duration 
for each method results in an estimate that less than one harbor 
porpoise may enter a Level A harassment zone during the project (see 
Table 14 of application). Given the relatively high density and larger 
size of the Level A isopleths for harbor porpoises (Table 5, high-
frequency cetaceans) we consider Level A harassment take is a 
possibility. However, we recognize that harbor porpoises travel in 
groups of up to 10 individuals and can be quick and somewhat cryptic, 
so there is potential that underwater mammals may go undetected before 
spotted in the Level A harassment and shutdown zone. Based on this 
observation we authorize Level A harassment take of 2 harbor porpoise.

California Sea Lion

    Density data for this species from SFOBB monitoring was 0.16/km\2\ 
(CalTrans 2018). Based on the different pile types and methods there 
are three different sized ensonified areas to be considered to estimate 
Level B harassment take (Table 7). Multiplication of the above density 
times the corresponding ensonified area and duration, and summing the 
results for the three methods, and subtracting the overlap of Level A 
take (below) to avoid double-counting of take, leads to authorized 
Level B harassment take of 20 California sea lions (Table 6).
    Similarly, calculating expected Level A harassment take as density 
times the corresponding Level A harassment ensonified area and duration 
for each method results in an estimate that less than one California 
sea lion will enter a Level A harassment zone (see Table 13

[[Page 37129]]

of application). Given the relatively high density and behavior of 
California sea lions we consider Level A harassment take is a 
possibility. Based on this observation we authorize Level A harassment 
take of 2 California sea lions.

Northern Fur Seal

    Density data for this species in the project vicinity do not exit. 
SFOBB monitoring showed no observations of this species (CalTrans 
2018). None were observed for the Treasure Island Ferry Dock project in 
2019 (Matt Osowski, personal communication). The Marine Mammal Center 
rescues about five northern fur seals in a year, and they occasionally 
rescue them from Yerba Buena Island and Treasure Island (TMMC, 2019). 
To be conservative we authorize Level B harassment take of three 
northern fur seals. Because the Level A harassment zones are relatively 
small and we believe the Protected Species Observer (PSO) will be able 
to effectively monitor the Level A harassment zones, and the species is 
rare, we do not authorize take by Level A harassment of northern fur 
seals.

Northern Elephant Seal

    Density data for this species in the project vicinity do not exist. 
SFOBB monitoring showed no observations of this species (CalTrans 
2018). None were observed for the Treasure Island Ferry Dock project in 
2019 (Matt Osowski, personal communication). Out of the approximately 
100 annual northern elephant seal strandings in San Francisco Bay, 
approximately 10 individuals strand nearby at Yerba Buena or Treasure 
Islands each year (TMMC, 2020). Therefore, we authorize the Level B 
harassment take of 5 northern elephant seals. Because the Level A 
harassment zones are relatively small and we believe the PSO will be 
able to effectively monitor the Level A harassment zones, and the 
species is rare, we do not authorize take by Level A harassment of 
northern elephant seals.

Harbor Seal

    Density data for this species from SFOBB monitoring was 3.92/km\2\ 
(CalTrans 2018). Based on the different pile types and methods there 
are three different sized ensonified areas to be considered to estimate 
Level B harassment take (Table 7). Multiplication of the above density 
times the corresponding ensonified area and duration, summing the 
results for the three methods, and subtracting the overlap of Level A 
take (below) to avoid double-counting of take, leads to authorized 
Level B harassment take of 527 harbor seals (Table 6).
    Similarly, calculating expected Level A harassment take as density 
times the corresponding Level A harassment ensonified area and duration 
for each method results in an estimate that less than one harbor seal 
may enter a Level A harassment zone during the project (see Table 12 of 
application). Given the relatively high density and size of the Level A 
isopleths for harbor seals (Table 5, phocid pinnipeds) we consider 
Level A harassment take is a possibility. We recognize that harbor 
seals can occur in moderate and rarely large size groups and can be 
quick and somewhat cryptic, so there is potential that underwater 
mammals may go undetected before spotted in the Level A harassment and 
shutdown zone. Based on this observation we authorize Level A 
harassment take of 2 harbor seals.

Gray Whale

    Density data for this species in the project vicinity do not exist. 
SFOBB monitoring showed no observations of this species (CalTrans 
2018). None were observed for the Treasure Island Ferry Dock project in 
2019 (Matt Osowski, personal communication). Approximately 12 gray 
whales were stranded in San Francisco Bay from January to May of 2019 
(TMMC, 2019) and four stranded in the vicinity on one week in 2021 
(https://www.washingtonpost.com/science/2021/04/11/whales-sf-bay-beaches/). Because recent observations are not well understood, 
Sausalito sits near the entrance to the bay, and as a conservative 
measure, we authorize Level B harassment take of 2 gray whales. Because 
the Level A harassment zones are relatively small and we believe the 
PSO will be able to effectively monitor the Level A harassment zones, 
and the species is rare, we do not authorize take by Level A harassment 
of gray whales.

  Table 6--Authorized Amount of Taking, by Level A Harassment and Level B Harassment, by Species and Stock and
                                            Percent of Take by Stock
----------------------------------------------------------------------------------------------------------------
                                                                      Level A         Level B       Percent of
         Common name            Scientific name       Stock         harassment      harassment         stock
----------------------------------------------------------------------------------------------------------------
Harbor seal..................  (Phoca vitulina)  California                    2             527             1.7
                                                  Stock.
Harbor porpoise..............  (Phocoena         San Francisco--               2              21             0.3
                                phocoena).        Russian River
                                                  Stock.
California sea lion..........  (Zalophus         U.S. Stock.....               2              20            <0.1
                                californianus).
Gray whale...................  (Eschrichtius     Eastern North                 0               2            <0.1
                                robustus).        Pacific Stock.
Bottlenose dolphin...........  (Tursiops         California                    0               9               2
                                truncatus).       Coastal Stock.
Northern elephant seal.......  (Mirounga         California                    0               5            <0.1
                                angustirostris).  Breeding Stock.
Northern fur seal............  (Callorhinus      California and                0               3            <0.1
                                ursinus).         Eastern North
                                                  Pacific Stocks.
----------------------------------------------------------------------------------------------------------------


                            Table 7--Calculations To Estimate Level B Harassment Take
----------------------------------------------------------------------------------------------------------------
                                                                                                      Harbor
                                                                    Harbor Seal      Sea Lion        Porpoise
----------------------------------------------------------------------------------------------------------------
SFOBB Species density (animals/square kilometer (km\2\))........            3.96            0.16            0.17
Days of Pile Driving/Cutting
    24-inch Concrete............................................              10              10              10
    14-inch Timber..............................................               6               6               6
    Pile Cutting................................................              10              10              10
Area of Isopleth in km\2\
    24-inch Concrete............................................         0.00151         0.00151         0.00151
    14-inch Timber..............................................         0.00151         0.00151         0.00151

[[Page 37130]]

 
    Pile Cutting................................................         13.3456         13.3456         13.3456
Per day take Level B
    24-inch Concrete............................................           0.006          0.0002          0.0003
    14-inch Timber..............................................           0.006          0.0002          0.0003
    Pile Cutting................................................         52.8486          2.1353          2.2688
                                                                 -----------------------------------------------
        Total Level B Take Calculated...........................          528.58           21.36           22.69
        Total Level B Take Estimated............................             529              22              23
----------------------------------------------------------------------------------------------------------------

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 the 
activity, and other means of effecting the least practicable impact on 
the species or stock and its habitat, paying particular attention to 
rookeries, mating grounds, and areas of similar significance, and on 
the availability of the 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 the 
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. 
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.
    The following mitigation measures are in the IHA:
     Avoid direct physical interaction with marine mammals 
during construction activity. If a marine mammal comes within 10 m of 
such activity, operations must cease and vessels must reduce speed to 
the minimum level required to maintain steerage and safe working 
conditions;
     Conduct training between construction supervisors and 
crews and the marine mammal monitoring team and relevant ACOE staff 
prior to the start of all pile driving activity and when new personnel 
join the work, so that responsibilities, communication procedures, 
monitoring protocols, and operational procedures are clearly 
understood;
     Pile driving activity must be halted upon observation of 
either a species for which incidental take is not authorized or a 
species for which incidental take has been authorized but the 
authorized number of takes has been met, entering or within the 
harassment zone;
     The ACOE will establish and implement the shutdown zones 
indicated in Table 9. The purpose of a shutdown zone is generally to 
define an area within which shutdown of the activity would occur upon 
sighting of a marine mammal (or in anticipation of an animal entering 
the defined area). Shutdown zones typically vary based on the activity 
type and marine mammal hearing group. The ACOE wishes to simplify 
implementation of the relatively small shutdown zones and has proposed 
using a single shutdown zone distance for each activity rather than 
separate zones for each hearing group as we minimally require 
typically. Therefore the shutdown zones in Table 8 are based on the 
largest possible Level A harassment zones calculated from the isopleths 
in Table 6.
     Employ PSOs and establish monitoring locations as 
described in the application and Section 5 of the IHA. The Holder must 
monitor the project area to the maximum extent possible based on the 
required number of PSOs, required monitoring locations, and 
environmental conditions for all pile driving and removal one PSO must 
be used. The PSO will be stationed as close to the activity as 
possible;
     The placement of the PSO during all pile driving and 
removal and drilling activities will ensure that the entire shutdown 
zone is visible during pile installation. Should environmental 
conditions deteriorate such that marine mammals within the entire 
shutdown zone will not be visible (e.g., fog, heavy rain), pile driving 
and removal must be delayed until the PSO is confident marine mammals 
within the shutdown zone could be detected;
     Monitoring must take place from 30 minutes prior to 
initiation of pile driving activity through 30 minutes post-completion 
of pile driving activity. Pre-start clearance monitoring must be 
conducted during periods of visibility sufficient for the lead PSO to 
determine the shutdown zones clear of marine mammals. Pile driving may 
commence following 30 minutes of observation when the determination is 
made;
     If pile driving is delayed or halted due to the presence 
of a marine mammal, the activity may not commence or resume until 
either the animal has voluntarily exited and been visually confirmed 
beyond the shutdown zone or 15 minutes have passed without re-detection 
of the animal;
     The ACOE must use soft start techniques when impact pile 
driving. Soft start requires contractors to provide an initial set of 
three strikes at reduced energy, followed by a 30-second waiting 
period, then two subsequent reduced-energy strike sets. A soft start 
must 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 
30 minutes or longer;
     Use a bubble curtain during impact pile driving and ensure 
that it is operated as necessary to achieve optimal performance, and 
that no reduction in performance may be

[[Page 37131]]

attributable to faulty deployment. At a minimum, the ACOE must adhere 
to the following performance standards: The bubble curtain must 
distribute air bubbles around 100 percent of the piling circumference 
for the full depth of the water column. The lowest bubble ring must be 
in contact with the substrate for the full circumference of the ring, 
and the weights attached to the bottom ring shall ensure 100 percent 
substrate contact. No parts of the ring or other objects shall prevent 
full substrate contact. Air flow to the bubblers must be balanced 
around the circumference of the pile.

     Table 8--Shutdown Zones (Meters) for Each Pile Type and Method
------------------------------------------------------------------------
               Pile size, type, and method                 Shutdown zone
------------------------------------------------------------------------
24-inch concrete, impact................................             140
14-inch timber, impact..................................              80
14 and 18-inch pile cutting.............................              10
------------------------------------------------------------------------

    Based on our evaluation of the applicant's proposed measures, as 
well as other measures considered by NMFS, NMFS has determined that the 
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.

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 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.

Visual Monitoring

     Monitoring must be conducted by qualified, NMFS-approved 
PSOs, in accordance with the following: PSOs must be independent (i.e., 
not construction personnel) and have no other assigned tasks during 
monitoring periods. At least one PSO must have prior experience 
performing the duties of a PSO during construction activity pursuant to 
a NMFS-issued incidental take authorization. Other PSOs may substitute 
other relevant experience, education (degree in biological science or 
related field), or training. PSOs must be approved by NMFS prior to 
beginning any activity subject to this IHA.
     PSOs must record all observations of marine mammals as 
described in the Section 5 of the IHA, regardless of distance from the 
pile being driven. PSOs shall document any behavioral reactions in 
concert with distance from piles being driven or removed;
    PSOs must have the following additional qualifications:
     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, times, and reason for implementation 
of mitigation (or why mitigation was not implemented when required); 
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;
     The ACOE must establish the following monitoring 
locations. For all pile driving and cutting activities, a minimum of 
one PSO must be assigned to the active pile driving or cutting location 
to monitor the shutdown zones and as much of the Level B harassment 
zones as possible.

Reporting

    A draft marine mammal monitoring report will be submitted to NMFS 
within 90 days after the completion of pile driving and removal 
activities, or 60 days prior to a requested date of issuance of any 
future IHAs for projects at the same location, whichever comes first. 
The report will include an overall description of work completed, a 
narrative regarding marine mammal sightings, and associated PSO data 
sheets. Specifically, the report must include:
     Dates and times (begin and end) of all marine mammal 
monitoring;
     Construction activities occurring during each daily 
observation period, including the number and type of piles driven or 
removed and by what method (i.e., impact or cutting) and the total 
equipment duration for cutting for each pile or total number of strikes 
for each pile (impact driving);
     PSO locations during marine mammal monitoring;
     Environmental conditions during monitoring periods (at 
beginning and end of PSO shift and whenever conditions change 
significantly), including Beaufort sea state and any other relevant 
weather conditions including cloud cover, fog, sun glare, and overall 
visibility to the horizon, and estimated observable distance;
     Upon observation of a marine mammal, the following 
information: Name of PSO who sighted the animal(s) and PSO location and 
activity at time of sighting; Time of sighting; Identification of the 
animal(s) (e.g., genus/species, lowest possible taxonomic level, or 
unidentified), PSO confidence in

[[Page 37132]]

identification, and the composition of the group if there is a mix of 
species; Distance and bearing of each marine mammal observed relative 
to the pile being driven for each sighting (if pile driving was 
occurring at time of sighting); Estimated number of animals (min/max/
best estimate); Estimated number of animals by cohort (adults, 
juveniles, neonates, group composition, etc.); Animal's closest point 
of approach and estimated time spent within the harassment zone; 
Description of any marine mammal behavioral observations (e.g., 
observed behaviors such as feeding or traveling), including an 
assessment of behavioral responses thought to have resulted from the 
activity (e.g., no response or changes in behavioral state such as 
ceasing feeding, changing direction, flushing, or breaching);
     Number of marine mammals detected within the harassment 
zones, by species; and
     Detailed information about any implementation of any 
mitigation triggered (e.g., shutdowns and delays), a description of 
specific actions that ensued, and resulting changes in behavior of the 
animal(s), if any.
    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.

Reporting Injured or Dead Marine Mammals

    In the event that personnel involved in the construction activities 
discover an injured or dead marine mammal, the IHA-holder must 
immediately cease the specified activities and report the incident to 
the Office of Protected Resources (OPR) 
([email protected]), NMFS and to West Coast Regional 
Stranding Coordinator as soon as feasible. If the death or injury was 
clearly caused by the specified activity, the ACOE must immediately 
cease the specified activities until NMFS is able to review the 
circumstances of the incident and determine what, if any, additional 
measures are appropriate to ensure compliance with the terms of the 
IHA. The IHA-holder must not resume their activities until notified by 
NMFS. The report must include the following information:
     Time, date, and location (latitude/longitude) of the first 
discovery (and updated location information if known and applicable);
     Species identification (if known) or description of the 
animal(s) involved;
     Condition of the animal(s) (including carcass condition if 
the animal is dead);
     Observed behaviors of the animal(s), if alive;
     If available, photographs or video footage of the 
animal(s); and
     General circumstances under which the animal was 
discovered.

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 and removal activities have the potential to disturb 
or displace marine mammals. Specifically, the project activities may 
result in take, in the form of Level A and Level B harassment from 
underwater sounds generated from pile driving and removal. Potential 
takes could occur if individuals are present in the ensonified zone 
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. The potential for 
harassment is minimized through the construction method and the 
implementation of the planned mitigation measures (see Mitigation 
section).
    The Level A harassment zones identified in Table 5 are based upon 
an animal exposed to impact pile driving multiple piles per day. 
Considering duration of impact driving each pile (up to 20 minutes) and 
breaks between pile installations (to reset equipment and move pile 
into place), this means an animal would have to remain within the area 
estimated to be ensonified above the Level A harassment threshold for 
multiple hours. This is highly unlikely given marine mammal movement 
throughout the area. If an animal was exposed to accumulated sound 
energy, the resulting PTS would likely be small (e.g., PTS onset) at 
lower frequencies where pile driving energy is concentrated, and 
unlikely to result in impacts to individual fitness, reproduction, or 
survival.
    The nature of the pile driving project precludes the likelihood of 
serious injury or mortality. For all species and stocks, take would 
occur within a limited, confined area (north-central San Francisco Bay 
including Richardson's Bay) of the stock's range. Level A and Level B 
harassment will be reduced to the level of least practicable adverse 
impact through use of mitigation measures described herein. Further the 
amount of take authorized is extremely small when compared to stock 
abundance.
    Behavioral responses of marine mammals to pile driving at the 
project site, if any, are expected to be mild and temporary. Marine 
mammals within the Level B harassment zone may not show any visual cues 
they are disturbed by activities (as noted during modification to the 
Kodiak Ferry Dock) or could become alert, avoid the area, leave the 
area, or display other mild responses that are not observable such as 
changes in vocalization patterns. Given the short duration of noise-
generating activities per day and that pile driving and removal would 
occur across nine months, any harassment would be temporary. There are 
no other areas or times of known biological importance for any of the 
affected species.
    In addition, 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

[[Page 37133]]

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.
    In summary and as described above, the following factors primarily 
support our 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;
     Authorized Level A harassment would be very small amounts 
and of low degree;
     No important habitat areas have been identified within the 
project area;
     For all species, San Francisco Bay is a very small and 
peripheral part of their range;
     The ACOE would implement mitigation measures such as 
bubble curtains, soft-starts, and shut downs; and
     Monitoring reports from similar work in San Francisco Bay 
have documented little to no effect on individuals of the same species 
impacted by the specified activities.
    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 monitoring and mitigation 
measures, NMFS 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 section 101(a)(5)(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. When the predicted number of individuals to 
be taken is fewer than one third of the species or stock abundance, the 
take is considered to be of small numbers. Additionally, other 
qualitative factors may be considered in the analysis, such as the 
temporal or spatial scale of the activities.
    The amount of take NMFS authorizes is below one third of the 
estimated stock abundance of all species (in fact, take of individuals 
is less than 10 percent of the abundance of the affected stocks, see 
Table 6). This is likely a conservative estimate because they assume 
all takes are of different individual animals which is likely not the 
case. Some individuals may return multiple times in a day, but PSOs 
would count them as separate takes if they cannot be individually 
identified.
    Based on the analysis contained herein of the proposed activity 
(including the mitigation and monitoring measures) and the anticipated 
take of marine mammals, NMFS 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

    There are no relevant subsistence uses of the affected marine 
mammal stocks or species implicated by this action. Therefore, NMFS has 
determined that the total taking of affected species or stocks would 
not have an unmitigable adverse impact on the availability of such 
species or stocks for taking for subsistence purposes.

Endangered Species Act

    Section 7(a)(2) of the 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 West Coast Region Protected Resources Division Office, 
whenever we propose to authorize take for endangered or threatened 
species.
    No incidental take of ESA-listed species is authorized or expected 
to result from this activity. Therefore, NMFS has determined that 
formal consultation under section 7 of the ESA is not required for this 
action.

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 IHA) 
with respect to potential impacts on the human environment.
    This action is consistent with categories of activities identified 
in Categorical Exclusion B4 (IHAs 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 determined 
that the issuance of the proposed IHA qualifies to be categorically 
excluded from further NEPA review.

Authorization

    NMFS has issued an IHA to the ACOE for the potential harassment of 
small numbers of seven marine mammal species incidental to the Debris 
Dock Replacement project in Sausalito, CA, provided the previously 
mentioned mitigation, monitoring and reporting requirements are 
followed.

    Dated: July 8, 2021.
Catherine Marzin,
Acting Director, Office of Protected Resources, National Marine 
Fisheries Service.
[FR Doc. 2021-14980 Filed 7-13-21; 8:45 am]
BILLING CODE 3510-22-P