[Federal Register Volume 82, Number 246 (Tuesday, December 26, 2017)]
[Notices]
[Pages 60954-60967]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2017-27761]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

RIN 0648-XF507


Takes of Marine Mammals Incidental to Specified Activities; 
Taking Marine Mammals Incidental to Boost-Back and Landing of Falcon 9 
Rockets

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 
Space Exploration Technology Corporation (SpaceX) to incidentally 
harass, by Level B harassment only, marine mammals during boost-back 
and landing of Falcon 9 rockets at Vandenberg Air Force Base in 
California, and at contingency landing locations in the Pacific Ocean.

DATES: This Authorization is valid from December 1, 2017, through 
November 30, 2018.

FOR FURTHER INFORMATION CONTACT: Jordan Carduner, 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: www.nmfs.noaa.gov/pr/permits/incidental/research.htm. In case of problems accessing these documents, 
please call the contact listed above.

SUPPLEMENTARY INFORMATION:

Background

    Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) 
direct the Secretary of Commerce to allow, upon request, the 
incidental, but not intentional, taking of small numbers of marine 
mammals by U.S. citizens who engage in a specified activity (other than 
commercial fishing) within a specified geographical region if certain 
findings are made and either regulations are issued or, if the taking 
is limited to harassment, a notice of a proposed authorization is 
provided to the public for review.
    An authorization for incidental takings shall be granted if NMFS 
finds that the taking will have a negligible impact on the species or 
stock(s), will not have an unmitigable adverse impact

[[Page 60955]]

on the availability of the species or stock(s) for subsistence uses 
(where relevant), and if the permissible methods of taking and 
requirements pertaining to the mitigation, monitoring and reporting of 
such takings are set forth.
    NMFS has defined ``negligible impact'' in 50 CFR 216.103 as an 
impact resulting from the specified activity that cannot be reasonably 
expected to, and is not reasonably likely to, adversely affect the 
species or stock through effects on annual rates of recruitment or 
survival.
    The MMPA states that the term ``take'' means to harass, hunt, 
capture, kill or attempt to harass, hunt, capture, or kill any marine 
mammal.
    Except with respect to certain activities not pertinent here, the 
MMPA defines ``harassment'' as: Any act of pursuit, torment, or 
annoyance which (i) has the potential to injure a marine mammal or 
marine mammal stock in the wild (Level A harassment); or (ii) has the 
potential to disturb a marine mammal or marine mammal stock in the wild 
by causing disruption of behavioral patterns, including, but not 
limited to, migration, breathing, nursing, breeding, feeding, or 
sheltering (Level B harassment).

Summary of Request

    NMFS received a request from SpaceX for an IHA to take marine 
mammals incidental to Falcon 9 First Stage recovery activities, 
including in-air boost-back maneuvers and landings of the First Stage 
of the Falcon 9 rocket at Vandenberg Air Force Base (VAFB) in 
California, and at contingency landing locations offshore. SpaceX's 
request was for harassment only and NMFS concurs that mortality is not 
expected to result from this activity. Therefore, an IHA is 
appropriate.
    SpaceX's application for incidental take authorization was received 
on July 11, 2017. SpaceX submitted a revised version of the request on 
October 13, 2017. This revised version of the application was deemed 
adequate and complete. The planned activity may exceed one year, hence 
subsequent MMPA incidental harassment authorizations may be requested 
for this particular activity.
    The planned activities include in-air boost-back maneuvers and 
landings of the First Stage of the Falcon 9 rocket. The action may 
occur as many as 12 times and may occur at any time of year. Species 
that are expected to be taken by the planned activity include harbor 
seal, California sea lion, Steller sea lion, northern elephant seal, 
northern fur seal, and Guadalupe fur seal. SpaceX's activities are 
expected to produce noise, in the form of sonic booms, that are 
expected to result in harassment of marine mammals that are hauled out 
of the water. Take by Level B harassment only is expected; no injury or 
mortality of marine mammals is expected to result from the activities.
    This is the second IHA issued by NMFS for this activity. SpaceX 
applied for, and was granted, an IHA in 2016 that was valid from June 
30, 2016 through June 29, 2017 (81 FR 34984; June 30, 2016). SpaceX 
complied with all the requirements (e.g., mitigation, monitoring, and 
reporting) of the previous IHA.

Description of Activity

    The Falcon 9 is a two-stage rocket designed and manufactured by 
SpaceX for transport of satellites and SpaceX's Dragon spacecraft into 
orbit. SpaceX currently operates the Falcon Launch Vehicle Program at 
Space Launch Complex 4E (SLC-4E) at VAFB. SpaceX plans to conduct 
recovery of the Falcon 9 First Stage by returning the First Stage to 
SLC-4 West (SLC-4W) at VAFB for potential reuse, up to twelve times per 
year. This includes performing in-air boost-back maneuvers and landings 
of the Falcon 9 First Stage on the pad at SLC-4W. The reuse of the 
Falcon 9 First Stage enables SpaceX to efficiently conduct lower cost 
launch missions from VAFB in support of commercial and government 
clients.
    Although SLC-4W is the preferred landing location, SpaceX has 
identified the need for contingency landing locations should it not be 
feasible to land the First Stage at SLC-4W. The first contingency 
landing option is on a barge located at least 27 nautical miles (nm) 
(50 kilometers (km)) offshore of VAFB. The second contingency landing 
option is on a barge within the Iridium Landing Area, an area 
approximately 33,153 square kilometers (km\2\) area that is located 
approximately 122 nm (225 km) southwest of San Nicolas Island and 133 
nm (245 km) southwest of San Clemente Island (see Figure 1-3 in the IHA 
application).
    During descent, a sonic boom (overpressure of high-energy impulsive 
sound) would be generated when the First Stage reaches a rate of travel 
that exceeds the speed of sound. Sonic booms would occur in proximity 
to the landing areas and may be heard during or briefly after the 
boost-back and landing, depending on the location of the observer. 
Sound from the sonic boom has the potential to result in harassment of 
marine mammals, either on the mainland at or near VAFB, or at the 
Northern Channel Islands (NCI). Based on model results, a boost-back 
and landing of the Falcon 9 First Stage at SLC-4W would produce sonic 
booms with overpressures that would potentially be as high as 8.5 
pounds per square foot (psf) at VAFB and potentially as high as 3.1 psf 
at the NCI. Sonic boom modeling indicates that landings that occur at 
either of the proposed contingency landing locations offshore would 
result in sonic booms below 1.0 psf. Take of marine mammals that are 
hauled out of the water are expected to occur only when those hauled 
out marine mammals experience sonic booms greater than 1.0 psf (this is 
discussed in greater detail below in the section on Estimated Take). 
Therefore, take of marine mammals may occur as a result of landings 
that occur at VAFB; however, take of marine mammals is not expected to 
occur as a result of landings that occur at either of the proposed 
contingency landing locations offshore. Sounds resulting from SpaceX's 
activities other than sonic booms, as well as other aspects of SpaceX's 
activities such as unsuccessful landings, are not expected to result in 
take of marine mammals and are not discussed further in this document.
    The activities authorized in this IHA are limited to Falcon 9 First 
Stage boost-back maneuvers and landings. Incidental take of marine 
mammals resulting from Falcon 9 rocket launches from VAFB is already 
authorized via regulations (79 FR 10016; February 24, 2014) and a 
Letter of Authorization (LOA) (79 FR 18528; April 2, 2014). As such, 
NMFS does not authorize take of marine mammals incidental to launches 
of the Falcon 9 rocket in this IHA; incidental take resulting from 
Falcon 9 rocket launches is therefore not analyzed further in this 
document.
    A detailed description of the planned activities is provided in the 
Federal Register notice of the proposed IHA (82 FR 49332; October 25, 
2017). Since that time, no changes have been made to the planned 
activities. Therefore, a more detailed description is not provided 
here. Please refer to that Federal Register notice for a more detailed 
description of the specific activities. Mitigation, monitoring, and 
reporting measures are described in detail later in this document 
(please see ``Mitigation'' and ``Monitoring and Reporting'').

Comments and Responses

    NMFS published a notice of proposed IHA in the Federal Register on 
October 25, 2017 (82 FR 49332). During the 30-day public comment 
period, NMFS received a comment letter from the Marine Mammal 
Commission (Commission). NMFS has posted the comments online at: http:/
/

[[Page 60956]]

www.nmfs.noaa.gov/pr/permits/incidental. The following is a summary of 
the public comments received and NMFS's responses.
    Comment 1: The Commission recommended that NMFS include Falcon 9 
recovery activities as a proposed amendment to the United States Air 
Force's (USAF) final rule (79 FR 10016; February 24, 2014) rather than 
authorizing those activities in separate IHAs until the rule expires in 
2019, and that NMFS ultimately include Falcon 9 recovery activities in 
the future proposed rule that will cover all other rocket activities 
conducted by USAF at VAFB beginning in 2019. The Commission also 
recommended that NMFS issue the IHA, subject to inclusion of the 
proposed mitigation, monitoring, and reporting measures, which are 
included as proposed in the final IHA.
    Response: NMFS agrees that streamlining in the MMPA incidental take 
authorization process is desirable when possible and we will work with 
the USAF to determine whether it is practicable to incorporate Falcon 9 
recovery activities in any future regulations governing the take of 
marine mammals incidental to rocket launch activities that occur at 
VAFB.

Description of Marine Mammals in the Area of Specified Activities

    Section 4 of the IHA application summarizes available information 
regarding status and trends, distribution and habitat preferences, and 
behavior and life history of the potentially affected species. We have 
reviewed SpaceX's species descriptions, including life history 
information, distribution, regional distribution, and acoustics and 
hearing, for accuracy and completeness, and we refer the reader to 
Section 4 of the IHA application, rather than reprinting the 
information here. A detailed description of the species likely to be 
affected by the specified activities, 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 of the 
proposed IHA (82 FR 49332; October 25, 2017). 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 (www.nmfs.noaa.gov/pr/species/mammals/) for 
generalized species accounts.
    Table 1 lists all marine mammal species with expected occurrence in 
the project area (including at VAFB, on the NCI, and in the waters 
surrounding VAFB, the NCI and the contingency landing location) that 
are expected to be affected by the specified activities, and summarizes 
information related to the populations, including regulatory status 
under the MMPA and Endangered Species Act (ESA). There are an 
additional 28 species of marine mammals (all cetaceans) with expected 
or possible occurrence in the project area. However, we have determined 
that sonic booms are the only potential stressor associated with the 
activity that could result in take of marine mammals, and that sonic 
booms only have the potential to result in harassment of marine mammals 
that are hauled out of the water. Therefore, we have concluded that the 
likelihood of the planned activities resulting in the harassment of any 
cetacean to be so low as to be discountable. As we have concluded that 
the likelihood of any cetacean being taken incidentally as a result of 
SpaceX's activities to be so low as to be discountable, cetaceans are 
not considered further in this document and no take of cetaceans is 
authorized in the IHA. Please see Table 3-1 in SpaceX's IHA application 
for a complete list of species with expected or potential occurrence in 
the project area.
    All values presented in Table 1 are the most recent available at 
the time of publication and are available in NMFS's stock assessment 
reports (SAR) (e.g., Carretta et al., 2017; Muto et al., 2017). Please 
see the SARs, available at www.nmfs.noaa.gov/pr/sars, for more detailed 
accounts of these stocks' status and abundance. Abundance estimates 
presented in Table 1 represent the total number of individuals that 
make up a given stock or the total number estimated within a particular 
study 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. PBR, 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, is considered in 
concert with known sources of ongoing anthropogenic mortality to assess 
the population-level effects of the anticipated mortality from a 
specific project (as described in NMFS's SARs). While no mortality is 
anticipated or authorized in this IHA, PBR and annual serious injury 
and mortality are included here as gross indicators of the status of 
the species and other threats. For taxonomy, we follow Committee on 
Taxonomy (2017). For status of species, we provide information 
regarding U.S. regulatory status under the MMPA and ESA.

                                         Table 1--Marine Mammal Species Potentially Present in the Project Area
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                  Stock abundance                                    Relative occurrence
                                                            ESA/MMPA status;      (CV, Nmin, most                      Annual M/SI     in project area;
             Species                       Stock          Strategic (Y/N) \1\     recent abundance       PBR \3\           \4\            season of
                                                                                    survey) \2\                                           occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                         Order Carnivora--Superfamily Pinnipedia
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                                                      Family Otariidae (eared seals and sea lions)
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California sea lion (Zalophus      U.S.................  -; N                   296,750 (n/a;                 9,200             389  Abundant; year-
 californianus).                                                                 153,337; 2011).                                      round.
Northern fur seal (Callorhinus     California..........  -; N                   14,050 (n/a; 7,524;             451             1.8  Abundant; year-
 ursinus).                                                                       2013).                                               round; peak
                                                                                                                                      occurrence during
                                                                                                                                      summer.
Guadalupe fur seal (Arctocephalus  n/a.................  T/D; Y                 20,000 (n/a;                    542             3.2  Rare; slightly more
 philippii townsendi).                                                           15,830; 2010).                                       common in summer.

[[Page 60957]]

 
Steller sea lion (Eumetopias       Eastern U.S.........  -; N                   71,562 (n/a;                  2,498             108  Rare; year-round.
 jubatus).                                                                       41,638; 2015).
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                             Family Phocidae (earless seals)
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Harbor seal (Phoca vitulina        California..........  -; N                   30,968 (n/a;                  1,641              43  Abundant; year-
 richardii).                                                                     27,348; 2012).                                       round.
Northern elephant seal (Mirounga   California breeding.  -; N                   179,000 (n/a;                 4,882             8.8  Abundant; year-
 angustirostris).                                                                81,368; 2010).                                       round; peak
                                                                                                                                      occurrence during
                                                                                                                                      winter.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ 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\ Potential biological removal, 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 size (OSP).
\4\ 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.

    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. Subsequently, NMFS (2016) described generalized hearing ranges 
for these marine mammal hearing groups. Generalized hearing ranges were 
chosen based on the approximately 65 decibels (dB) threshold from the 
normalized composite audiograms. The relevant functional groups and the 
associated frequencies are indicated below (note that these frequency 
ranges correspond to the range for the composite group, with the entire 
range not necessarily reflecting the capabilities of every species 
within that group):
     Pinnipeds in water; Phocidae (true seals): generalized 
hearing is estimated to occur between approximately 50 hertz (Hz) to 86 
kilohertz (kHz), with best hearing between 1-50 kHz;
     Pinnipeds in water; Otariidae (eared seals): generalized 
hearing is estimated to occur between 60 Hz and 39 kHz, with best 
hearing between 2-48 kHz.
    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).

   Table 2--Relevant Marine Mammal Functional Hearing Groups and Their
                       Generalized Hearing Ranges
------------------------------------------------------------------------
              Hearing group                  Generalized hearing range*
------------------------------------------------------------------------
Phocid pinnipeds (PW) (underwater) (true   50 Hz to 86 kHz.
 seals).
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 PW pinniped
  (approximation).

    For more detail concerning these groups and associated frequency 
ranges, please see NMFS (2016) for a review of available information. 
Of the six marine mammal species that may be affected by the planned 
activities, four are classified as otariids and two are classified as 
phocids.

Potential Effects of Specified Activities on Marine Mammals and Their 
Habitat

    The effects of noise from SpaceX's activities have the potential to 
result in behavioral harassment of marine mammals in the vicinity of 
the action area. The Federal Register notice of proposed IHA (82 FR 
49332; October 25, 2017) included a discussion of the effects of 
anthropogenic noise on marine mammals and their habitat, therefore that 
information is not repeated here; please refer to that Federal Register 
notice for that information. No instances of injury, serious injury or 
mortality are expected as a result of SpaceX's activities.

Estimated Take by Incidental Harassment

    This section provides an estimate of the number of incidental takes 
authorized through this IHA, which will inform both NMFS' consideration 
of whether the number of takes is ``small'' 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

[[Page 60958]]

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).
    All authorized takes are by Level B harassment only, in the form of 
disruption of behavioral patterns for individual marine mammals 
resulting from exposure to sounds associated with the planned 
activities. Based on the nature of the activity, Level A harassment, 
serious injury, and mortality are neither anticipated nor authorized in 
this IHA.
    Described in the most basic way, we estimate take by considering: 
(1) Acoustic thresholds above which NMFS believes the best available 
science indicates marine mammals will be behaviorally harassed; (2) the 
area 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 number of days of activities. Below, we describe these 
components in more detail and present the take estimate.

Acoustic Thresholds

    Using the best available science, NMFS has developed acoustic 
thresholds that identify the received level of 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). As described above, Level A harassment 
is not expected to occur as a result of the planned activities and we 
do not authorize take by Level A harassment, thus criteria and 
thresholds for Level A harassment are not discussed further. Thresholds 
have been developed identifying the received level of in-air sound 
above which exposed pinnipeds would likely be behaviorally harassed. In 
this case, we are concerned only with in-air sound as the planned 
activities are not expected to result in harassment of marine mammals 
that are underwater. Thus, only in-air thresholds are discussed 
further.

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, and the 
receiving animals (hearing, motivation, experience, demography, 
behavioral context) and can be difficult to predict (Southall et al., 
2007, Ellison et al., 2011). 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 
typically uses a generalized acoustic threshold based on received level 
to estimate the onset of behavioral harassment. For in-air sounds, NMFS 
expects that harbor seals exposed to sound above received levels of 90 
dB re 20 micro Pascals ([mu]Pa) (root mean squared (rms)) will be 
behaviorally harassed, and all other species of pinnipeds exposed to 
sound above received levels of 100 dB re 20 [mu]Pa (rms) will be 
behaviorally harassed (Table 3).

 Table 3--Recommended Criteria for Pinniped Harassment From Exposure to
                             Airborne Sound
------------------------------------------------------------------------
               Species                    Level B harassment threshold
------------------------------------------------------------------------
Harbor seals.........................  90 dB re 20 [mu]Pa.
All other pinniped species...........  100 dB re 20 [mu]Pa.
------------------------------------------------------------------------

    Typically, NMFS relies on the acoustic criteria shown in Table 3 to 
estimate take as a result of exposure to airborne sound from a given 
activity. However, in this case we have the benefit of more than 20 
years of observational data on pinniped responses to the stimuli 
associated with the planned activity that we expect to result in 
harassment (sonic booms) in the particular geographic area of the 
planned activity (VAFB and the NCI). Therefore, we consider these data 
to be the best available information in regard to estimating take based 
on modeled exposures among pinnipeds to sounds associated with the 
planned activities. These data suggest that pinniped reactions to sonic 
booms are dependent on the species and the intensity of the sonic boom 
(Table 4).
    The USAF has monitored pinniped responses to rocket launches from 
VAFB for over 20 years. Though rocket launches are not part of the 
planned activities (as described above), the acoustic stimuli 
associated with launches (e.g., sonic booms) is expected to be 
substantially similar to those expected to occur with Falcon 9 boost-
backs and landings; therefore, we rely on observational data on 
responses of pinnipeds to sonic booms associated with rocket launches 
from VAFB in making assumptions about expected pinniped responses to 
sonic booms associated with Falcon 9 boost-backs and landings.
    Observed reactions of pinnipeds at the NCI and at VAFB to sonic 
booms have ranged from no response to heads-up alerts, from startle 
responses to some movements on land, and from some movements into the 
water to occasional stampedes (especially involving California sea 
lions on the NCI). We therefore assume sonic booms generated during the 
return flight of the Falcon 9 First Stage may elicit an alerting or 
other short-term behavioral reaction, including flushing into the water 
if hauled out.
    Data from launch monitoring by the USAF has shown that pinniped 
reactions to sonic booms are correlated with the level of the sonic 
boom. Low energy sonic booms (<1.0 psf have resulted in little to no 
behavioral responses, including head raising and briefly alerting but 
returning to normal behavior shortly after the stimulus (Table 4). More 
powerful sonic booms have resulted in pinnipeds flushing from haulouts. 
No pinniped mortalities have been associated with sonic booms. No 
sustained decreases in numbers of animals observed at haulouts have 
been observed after the stimulus. Table 4 presents a summary of 
monitoring efforts at the NCI from 1999 to 2014. These data show that 
reactions to sonic booms tend to be insignificant below 1.0 psf and 
that, even above 1.0 psf, only a portion of the animals present have 
reacted to the sonic boom. Time-lapse video photography during four 
launch events revealed that harbor seals that reacted to the rocket 
launch noise but did not leave the haul-out were all adults.
    Data from previous monitoring also suggests that for those 
pinnipeds that flush from haulouts in response to sonic booms, the 
amount of time it takes for those animals to begin returning to the 
haulout site, and for numbers of animals to return to pre-launch 
levels, is correlated with sonic boom sound levels. Pinnipeds may begin 
to return to the haulout site within 2-55 minutes of the launch 
disturbance, and the haulout site usually returned to pre-launch levels 
within 45-120 minutes.
    Monitoring data has consistently shown that reactions among 
pinnipeds vary between species, with harbor seals and California sea 
lions tending to be more sensitive to disturbance than northern 
elephant seals and northern fur seals (Table 4). Because Steller sea 
lions and Guadalupe fur seals occur in the project area relatively 
infrequently, no data has been recorded on their reactions to sonic 
booms. At VAFB, harbor seals generally alert to nearby

[[Page 60959]]

launch noises, with some or all of the animals going into the water. 
Usually the animals haul out again from within minutes to two hours or 
so of the launch, provided rising tides or breakers have not submerged 
the haul-out sites. Post-launch surveys often indicate as many or more 
animals hauled out than were present at the time of the launch, unless 
rising tides, breakers or other disturbances are involved (SAIC 2012). 
When launches occurred during high tides at VAFB, no impacts have been 
recorded because virtually all haulout sites were submerged.
    At the Channel Islands, California sea lions have been observed to 
react strongly to sonic booms relative to other species present. 
California sea lion pups have sometimes reacted more than adults, 
either because they are more easily frightened or because their hearing 
is more acute. Harbor seals also generally appear to be more sensitive 
to sonic booms than most other pinnipeds, often startling and fleeing 
into the water. Northern fur seals generally show little or no 
reaction. Northern elephant seals generally exhibit no reaction at all, 
except perhaps a heads-up response or some stirring, especially if sea 
lions in the same area or mingled with the elephant seals react 
strongly to the boom. Post-launch monitoring generally reveals a return 
to normal patterns within minutes up to an hour or two of each launch, 
regardless of species (SAIC 2012).
    Table 4 summarizes monitoring efforts at San Miguel Island during 
which acoustic measurements were successfully recorded and during which 
pinnipeds were observed. During more recent launches, night vision 
equipment was used. The table shows only monitoring data for launches 
during which sonic booms were heard and recorded. The table shows that 
little or no reaction from the four species usually occurs when 
overpressures are below 1.0 psf. In general, as described above, 
elephant seals do not react unless other animals around them react 
strongly or if the sonic boom is extremely loud, and northern fur seals 
seem to react similarly. Not enough data exist to draw conclusions 
about harbor seals at the NCI, but considering their reactions to 
launch noise at VAFB, it is likely that they are also sensitive to 
sonic booms (SAIC 2012).

                    Table 4--Observed Pinniped Responses to Sonic Booms at San Miguel Island
----------------------------------------------------------------------------------------------------------------
                                          Sonic boom                                   Species and associated
             Launch event                 level (psf)      Monitoring location               reactions
----------------------------------------------------------------------------------------------------------------
Athena II (April 27, 1999)............             1.0  Adams Cove...............  California sea lion--866
                                                                                    alerted; 232 (27%) flushed
                                                                                    into water.
                                                                                   Northern elephant seal--
                                                                                    alerted but did not flush.
                                                                                   Northern fur seal--alerted
                                                                                    but did not flush.
Athena II (September 24, 1999)........            0.95  Point Bennett............  California sea lion--12 of
                                                                                    600 (2%) flushed into water.
                                                                                   Northern elephant seal--
                                                                                    alerted but did not flush.
                                                                                   Northern fur seal--alerted
                                                                                    but did not flush.
Delta II 20 (November 20, 2000).......             0.4  Point Bennett............  California sea lion--60 pups
                                                                                    flushed into water; no
                                                                                    reaction from focal group.
                                                                                   Northern elephant seal--no
                                                                                    reaction.
Atlas II (September 8, 2001)..........            0.75  Cardwell Point...........  California sea lion (Group
                                                                                    1)--no reaction (1,200
                                                                                    animals).
                                                                                   California sea lion (Group
                                                                                    2)--no reaction (247
                                                                                    animals).
                                                                                   Northern elephant seal--no
                                                                                    reaction.
                                                                                   Harbor seal--2 of 4 flushed
                                                                                    into water.
Delta II (February 11, 2002)..........            0.64  Point Bennett............  California sea lion and
                                                                                    northern fur seal--no
                                                                                    reaction among 485 animals
                                                                                    in 3 groups.
                                                                                   Northern elephant seal--no
                                                                                    reaction among 424 animals
                                                                                    in 2 groups.
Atlas II (December 2, 2003)...........            0.88  Point Bennett............  California sea lion--
                                                                                    approximately 40% alerted;
                                                                                    several flushed to water
                                                                                    (number unknown--night
                                                                                    launch).
                                                                                   Northern elephant seal--no
                                                                                    reaction.
Delta II (July 15, 2004)..............            1.34  Adams Cove...............  California sea lion--10%
                                                                                    alerted (number unknown--
                                                                                    night launch).
Atlas V (March 13, 2008)..............            1.24  Cardwell Point...........  Northern elephant seal--no
                                                                                    reaction (109 pups).
Delta II (May 5, 2009)................            0.76  West of Judith Rock......  California sea lion--no
                                                                                    reaction (784 animals).
Atlas V (April 14, 2011)..............            1.01  Cuyler Harbor............  Northern elephant seal--no
                                                                                    reaction (445 animals).
Atlas V (September 13, 2012)..........            2.10  Cardwell Point...........  California sea lion--no
                                                                                    reaction (460 animals).
                                                                                   Northern elephant seal--no
                                                                                    reaction (68 animals).
                                                                                   Harbor seal--20 of 36 (56%)
                                                                                    flushed into water.
Atlas V (April 3, 2014)...............            0.74  Cardwell Point...........  Harbor seal--1 of ~25 flushed
                                                                                    into water; no reaction from
                                                                                    others.
Atlas V (December 12, 2014)...........            1.16  Point Bennett............  Calif. sea lion--5 of ~225
                                                                                    alerted; none flushed.
----------------------------------------------------------------------------------------------------------------

    As described above, data from launch monitoring by the USAF on the 
NCI and at VAFB have shown that pinniped reactions to sonic booms are 
correlated to the level of the sonic boom. Low energy sonic booms (<1.0 
psf) have typically resulted in little to no behavioral responses, 
including head raising and briefly alerting but returning to normal 
behavior shortly after the stimulus. More powerful sonic booms have 
flushed animals from haulouts (but not resulted in any mortality or 
sustained decreased in numbers after the stimulus). Monitoring data 
from the NCI and VAFB from 1999 to 2014 show that reactions to sonic 
booms tend to be insignificant below 1.0 psf and that, even above 1.0 
psf, only a portion of the animals present react to the sonic boom 
(Table 4). Therefore, for the purposes of estimating the extent of take 
that is likely to occur as a result of the planned activities, we 
assume that Level B harassment occurs when a pinniped (on land) is 
exposed to a sonic boom at or above 1.0 psf. Therefore, the number of 
expected takes by Level B harassment is based on estimates of the 
numbers of animals that would be within the areas exposed to sonic 
booms at levels at or above 1.0 psf.

Ensonified Area

    As described above, modeling was performed to estimate overpressure 
levels that would be created during sonic booms that occur during the 
return flight of the Falcon 9 First Stage.

[[Page 60960]]

The predicted acoustic footprint of the sonic boom was computed using 
the computer program PCBoom (Plotkin and Grandi 2002; Page et al. 
2010). As described above, the highest sound generated by a sonic boom 
would generally be focused on the area where the Falcon 9 ultimately 
lands. Based on model results, a boost-back and landing of the Falcon 9 
First Stage at SLC-4W would produce a sonic boom with overpressures as 
high as 8.5 psf at SLC-4W, which would attenuate to levels below 1.0 
psf at approximately 15.90 mi. (25.59 km) from the landing area (Figure 
2-2 in the IHA application). This estimate is based, in part, on actual 
observations from Falcon 9 boost-back and landing activities at Cape 
Canaveral, Florida. A boost-back and landing of the Falcon 9 First 
Stage at SLC-4W would produce a sonic boom with overpressures up to 3.1 
psf on the NCI, based on model results.
    During a contingency barge landing event, sonic boom overpressure 
would be directed at the ocean surface while the first-stage booster is 
supersonic. Model results indicate that sonic booms would not exceed 
1.0 psf on any part of the NCI during a boost-back and landing of the 
Falcon 9 First Stage at the contingency landing location at least 27 nm 
(50 km) offshore (Figure 2-6 and Figure 2-7 in the IHA application). 
Additionally, First Stage boost-backs and landings within the Iridium 
Landing Area would not likely produce measurable overpressures at any 
land surface (Figure 2-8 and Figure 2-9 in the IHA application). 
Therefore, take of marine mammals is not expected to occur as a result 
of boost-back and landing activities at the contingency landing 
location at least 27 nm (50 km) offshore, nor within the Iridium 
Landing Area. Estimated takes are therefore based on the possibility of 
boost-back and landing activities occurring at SLC-4W.

Marine Mammal Occurrence

    In this section we provide the information about the presence, 
density, or group dynamics of marine mammals that will inform the take 
calculations. Data collected from marine mammal surveys, including 
monthly marine mammal surveys conducted by the USAF at VAFB as well as 
data collected by NMFS, represent the best available information on the 
occurrence of the six pinniped species expected to occur in the project 
area. The quality and amount of information available on pinnipeds in 
the project area varies depending on species; some species are surveyed 
regularly at VAFB and the NCI (e.g., California sea lion), while other 
species are surveyed less frequently (e.g., northern fur seals and 
Guadalupe fur seals). However, the best available data was used to 
estimate take numbers. Take estimates for all species are shown in 
Table 6.
    Harbor Seal--Pacific harbor seals are the most common marine mammal 
inhabiting VAFB, congregating on several rocky haulout sites along the 
VAFB coastline. They also haul out, breed, and pup in isolated beaches 
and coves throughout the coasts of the NCI. Harbor seals may be exposed 
to sonic booms above 1.0 psf on the mainland and the NCI. Take of 
harbor seals at VAFB was estimated based on the maximum count totals 
from monthly surveys of VAFB haulout sites from 2013-2016 (ManTech SRS 
Technologies, Inc., 2014, 2015, 2016; VAFB, unpubl. data). Take of 
harbor seals at the NCI and at Point Conception was estimated based on 
the maximum count totals from aerial survey data collected from 2002 to 
2012 by the NMFS Southwest Fisheries Science Center (SWFSC) (Lowry et 
al., 2017).
    California sea lion-- California sea lions are common offshore of 
VAFB and haul out on rocks and beaches along the coastline of VAFB, 
though pupping rarely occurs on the VAFB coastline. They haul out in 
large numbers on the NCI and rookeries exist on San Miguel and Santa 
Cruz islands. California sea lions may be exposed to sonic booms above 
1.0 psf on the mainland and the NCI. Take of California sea lions at 
VAFB was estimated based on the maximum count totals from monthly 
surveys of VAFB haulout sites from 2013-2016 (ManTech SRS Technologies, 
Inc., 2014, 2015, 2016; VAFB, unpubl. data). Take of California sea 
lions at the NCI was estimated based on the maximum count totals from 
aerial survey data collected from 2002 to 2012 by the SWFSC (Lowry et 
al., 2017). We note that in the Federal Register notice of the proposed 
IHA (82 FR 49332; October 25, 2017) we estimated takes of California 
sea lions on Santa Cruz Island (811 takes of California sea lions were 
estimated per boost-back and landing activity). However, since the 
notice of the proposed IHA was published, we have reviewed the sonic 
boom models presented in the IHA application and determined that a 
sonic boom of 1.0 psf or above is not expected to impact Santa Cruz 
Island, and, therefore, no takes of marine mammals on Santa Cruz Island 
are expected to occur as a result of the specified activities. 
Therefore we do not authorize any takes of California sea lions on 
Santa Cruz Island in this IHA.
    Steller Sea Lion--Steller sea lions occur in small numbers at VAFB 
and on San Miguel Island. They have not been observed on the Channel 
Islands other than at San Miguel Island and they do not currently have 
rookeries at VAFB or the NCI. Steller sea lions may be exposed to sonic 
booms above 1.0 psf on the mainland and the NCI. Take of Steller sea 
lions at VAFB was estimated based on the largest count totals from 
monthly surveys of VAFB haulout sites from 2013-2016 (ManTech SRS 
Technologies, Inc., 2014, 2015, 2016; VAFB, unpubl. data). Steller sea 
lions haul out in very small numbers on the NCI, and comprehensive 
survey data for Steller sea lions in the NCI is not available. Take of 
Steller sea lions at the NCI was estimated based on subject matter 
expert input suggesting that as many as four Steller sea lions have 
been observed on San Miguel Island at a time (pers. comm., S. Melin, 
NMFS Marine Mammal Laboratory (MML), to J. Carduner, NMFS, Feb 11, 
2016).
    Northern elephant seal--Northern elephant seals haul out 
sporadically on rocks and beaches along the coastline of VAFB and at 
Point Conception and have rookeries on San Miguel Island and Santa Rosa 
Island and at one location at VAFB. Northern elephant seals may be 
exposed to sonic booms above 1.0 psf on the mainland and the NCI. Take 
of northern elephant seals at VAFB was estimated based on the largest 
count totals from monthly surveys of VAFB haulout sites from 2013-2016 
(ManTech SRS Technologies, Inc., 2014, 2015, 2016; VAFB, unpubl. data). 
Take of northern elephant seals at the NCI and at Point Conception was 
estimated based on the maximum count totals from aerial survey data 
collected from 2002 to 2012 by the NMFS SWFSC (Lowry et al., 2017).
    Northern fur seal--Northern fur seals have rookeries on San Miguel 
Island, the only island in the NCI on which they have been observed. No 
haulouts or rookeries exist for northern fur seals on the mainland 
coast, including VAFB, thus they may be exposed to sonic booms above 
1.0 psf at the NCI but not on the mainland. Comprehensive survey data 
for northern fur seals in the project area is not available. Estimated 
take of northern fur seals was based on subject matter expert input 
which suggested a maximum of approximately 6,000-8,000 northern fur 
seals may be present on San Miguel Island at the height of breeding/
pupping season (early July). After the height of the breeding/pupping 
season, numbers fluctuate but decrease as females go on foraging trips 
and males begin to migrate in late July/August. Numbers continue to 
decrease

[[Page 60961]]

until November when most of the population is absent from the island 
until the following breeding/pupping period (starting the following 
June) (pers. comm., T. Orr, NMFS NMML, to J. Carduner, NMFS OPR, 
February 27, 2016). It was therefore conservatively estimated that 
numbers peak at 8,000 animals hauled out at any given time in July and 
decrease to a minimum of 2,000 animals hauled out at any given time in 
the winter, then increase again until the following July. This results 
in an average estimate of 5,000 northern fur seals hauled out at San 
Miguel Island at any given time over the course of the entire year.
    Guadalupe fur seal--There are estimated to be approximately 20-25 
individual Guadalupe fur seals that have fidelity to San Miguel Island 
(pers. comm. S. Mellin, NMFS NMML, to J. Carduner, NMFS OPR, February 
11, 2016). No haulouts or rookeries exist for Guadalupe fur seals on 
the mainland coast, including VAFB, thus they may be exposed to sonic 
booms above 1.0 psf at the NCI but not on the mainland. Comprehensive 
survey data on Guadalupe fur seals in the project area is not readily 
available. Estimated take of Guadalupe fur seals was based on the 
maximum number of Guadalupe fur seals observed at any one time on San 
Miguel Island (13) (pers. comm., J. LaBonte, ManTech SRS Technologies 
Inc., to J. Carduner, NMFS, Feb. 29, 2016); it was therefore 
conservatively assumed that 13 Guadalupe fur seals may be hauled out at 
San Miguel Island at any given time.
Take Calculation and Estimation
    Here we describe how the information provided above is brought 
together to produce a quantitative take estimate.
    NMFS currently uses a three-tiered scale to determine whether the 
response of a pinniped on land to acoustic or visual stimuli is 
considered an alert, a movement, or a flush. NMFS considers the 
behaviors that meet the definitions of both movements and flushes to 
qualify as behavioral harassment. Thus a pinniped on land is considered 
by NMFS to have been behaviorally harassed if it moves greater than two 
times its body length, or if the animal is already moving and changes 
direction and/or speed, or if the animal flushes from land into the 
water. Animals that become alert without such movements are not 
considered harassed. See Table 5 for a summary of the pinniped 
disturbance scale.

                           Table 5--Levels of Pinniped Behavioral Disturbance on Land
----------------------------------------------------------------------------------------------------------------
                                                                                       Classified as behavioral
               Level                   Type of response            Definition             harassment by NMFS
----------------------------------------------------------------------------------------------------------------
1.................................  Alert................  Head orientation or brief  No.
                                                            movement in response to
                                                            disturbance, which may
                                                            include turning head
                                                            towards the disturbance,
                                                            craning head and neck
                                                            while holding the body
                                                            rigid in a u-shaped
                                                            position, changing from
                                                            a lying to a sitting
                                                            position, or brief
                                                            movement of less than
                                                            twice the animal's body
                                                            length.
2.................................  Movement.............  Movements in response to   Yes.
                                                            the source of
                                                            disturbance, ranging
                                                            from short withdrawals
                                                            at least twice the
                                                            animal's body length to
                                                            longer retreats over the
                                                            beach, or if already
                                                            moving a change of
                                                            direction of greater
                                                            than 90 degrees.
3.................................  Flush................  All retreats (flushes) to  Yes.
                                                            the water.
----------------------------------------------------------------------------------------------------------------

    As described above, the likelihood of pinnipeds exhibiting 
responses to sonic booms that would be considered behavioral harassment 
(based on the levels of pinniped disturbance as shown in Table 5) is 
dependent on both the species and on the intensity of the sonic boom. 
Data from rocket launch monitoring by the USAF at VAFB and the NCI show 
that pinniped reactions to sonic booms are correlated to the level of 
the sonic boom, with low energy sonic booms (<1.0 psf) typically 
resulting in little to no behavioral responses, and higher energy sonic 
booms resulting in responses ranging from no response to heads-up 
alerts, startle responses, some movements on land, and some movements 
into the water (flushing). Based on model results, a boost-back and 
landing of the Falcon 9 First Stage at SLC-4W would produce a sonic 
boom with greater intensity at VAFB (overpressures potentially as high 
as 8.5 psf) than at the NCI (overpressures potentially as high as 3.1 
psf). Responses of pinnipeds to sonic booms are also highly dependent 
on species, with harbor seals, California sea lions and Steller sea 
lions generally displaying greater sensitivity to sonic booms than 
northern elephant seals and northern fur seals (Table 4). We are not 
aware of any data on Guadalupe fur seal responses to sonic booms, but 
we assume responses by Guadalupe fur seal responses to be similar to 
those observed in northern fur seals as the two species are 
physiologically and behaviorally very similar.
    Take estimates were calculated by overlaying the modeled acoustic 
footprints of sonic booms from boost-back and landing events at SLC-4W 
with known pinniped haulouts on the mainland (including those at VAFB) 
and the NCI to determine the pinniped haulouts that would potentially 
be affected by sonic booms with overpressures of 1.0 psf and above. 
Only haulouts along northeastern San Miguel Island and northern and 
northwestern Santa Rosa Island would be expected to experience 
overpressures greater than 1.0 psf during a boost-back and landing at 
SLC-4W (Figures 2-3, 2-4, 2-5 and 2-6 in the IHA application). Take 
estimates also account for the likely intensity of the sonic boom as 
well as the relative sensitivity of the marine mammal species present, 
based on monitoring data as described above.
    A boost-back and landing of the Falcon 9 First Stage at SLC-4W that 
results in a sonic boom of 1.0 psf and above at VAFB was conservatively 
estimated to result in behavioral harassment of 100 percent of all 
species hauled out at or near VAFB and Point Conception (Table 6). A 
boost-back and landing of the Falcon 9 First Stage at SLC-4W that 
results in a sonic boom of 1.0 psf and above at the NCI was estimated 
to result in the behavioral harassment of 100 percent of California sea 
lions, harbor seals, and Steller sea lions that are hauled out at the 
NCI and of five percent of northern elephant seals, northern fur seals, 
and Guadalupe fur seals that are hauled out at the NCI. The five 
percent adjustment in the take estimates for these species at the NCI 
is also considered conservative, as launch monitoring data shows that 
elephant seals and fur seals sometimes alert to sonic booms but have 
never been observed flushing to the water or

[[Page 60962]]

responding in a manner that would be classified as behavioral 
harassment even when sonic booms were measured at >1.0 psf (see Table 4 
for a summary of launch monitoring data).
    The take calculations presented in Table 6 are based on the best 
available information on marine mammal populations in the project 
location and responses among marine mammals to the stimuli associated 
with the planned activities.

 Table 6--Estimated Numbers of Marine Mammals, and Percentage of Marine Mammal Populations, Potentially Taken as
                                       a Result of the Planned Activities
----------------------------------------------------------------------------------------------------------------
                                                     Estimated       Estimated
                                                     number of       combined      Total number   Takes by level
                                                      level B        number of      of takes by    B harassment
            Species                Geographic       harassment        level B         level B      authorized as
                                    location       exposures per    harassment      harassment     a percentage
                                                     event, by     exposures per  authorized \1\   of population
                                                     location          event
----------------------------------------------------------------------------------------------------------------
Pacific Harbor Seal \2\.......  VAFB............             366           1,384          16,608             4.4
                                Pt. Conception..             516
                                San Miguel                   310
                                 Island.
                                Santa Rosa                   192
                                 Island.
                                Santa Cruz                     0
                                 Island.
California Sea Lion...........  VAFB............             416           3,750          45,000            15.2
                                Pt. Conception..             N/A
                                San Miguel                 2,134
                                 Island.
                                Santa Rosa                 1,200
                                 Island.
                                Santa Cruz                     0
                                 Island.
Northern Elephant Seal........  VAFB............             190             227           2,724             1.5
                                Pt. Conception..              11
                                San Miguel                    18
                                 Island \3\.
                                Santa Rosa                     8
                                 Island \3\.
                                Santa Cruz                     0
                                 Island.
Steller Sea Lion..............  VAFB............              16              20             240             0.3
                                Pt. Conception..             N/A
                                San Miguel                     4
                                 Island.
                                Santa Rosa                   N/A
                                 Island.
                                Santa Cruz                   N/A
                                 Island.
Northern Fur Seal.............  VAFB............             N/A             250           3,000            21.4
                                Pt. Conception..             N/A
                                San Miguel                   250
                                 Island \ 3\.
                                Santa Rosa                   N/A
                                 Island.
                                Santa Cruz                   N/A
                                 Island.
Guadalupe Fur Seal............  VAFB............             N/A               1              12             0.1
                                Pt. Conception..             N/A
                                San Miguel                     1
                                 Island \3\.
                                Santa Rosa                   N/A
                                 Island.
                                Santa Cruz                   N/A
                                 Island.
----------------------------------------------------------------------------------------------------------------
\1\ Based on twelve boost-back and landing events. Total number of takes authorized represents incidences of
  harassment and not necessarily individuals.
\2\ As the same individual harbor seals are likely to be taken repeatedly over the course of the specified
  activities, we use the estimate of 1,384 individual animals taken per Falcon 9 First Stage recovery activity
  for the purposes of estimating the percentage of stock abundance likely to be taken over the course of the
  entire activity.
\3\ Number shown reflects five percent of total number of predicted potential exposures, i.e. five percent of
  animals exposed to sonic booms above 1.0 psf at these locations are assumed to experience Level B harassment.

    Take estimates are believed to be conservative based on the 
assumption that all twelve Falcon 9 First Stage recovery activities 
would result in landings at SLC-4W, with no landings occurring at 
contingency landing locations. However, some or all actual landing 
events may ultimately occur at the contingency landing locations; as 
described above, landings at the contingency landing locations would be 
expected to result in no takes of marine mammals. However, the number 
of landings at each location is not known in advance, therefore, we 
assume all landings would occur at SLC-4W. In addition, as described 
above, it is conservatively assumed that 100 percent of any species of 
pinniped hauled out on the mainland (VAFB and Point Conception), and 
100 percent of harbor seals, California sea lions and Steller sea lions 
hauled out at the NCI, would be harassed (Level B harassment only) by a 
Falcon 9 boost-back and landing event at SLC-4W that results in a sonic 
boom of >1.0 psf. However, it is possible that less than this 
percentage of hauled out pinnipeds will be behaviorally harassed by a 
Falcon 9 boost-back and landing at SLC-4W. While there may be some 
limited behavioral harassment of pinnipeds that occurs at psf levels 
<1.0, we account for that in the overall conservativeness of the total 
take number, as described above.
    As described above, in the Federal Register notice of the proposed 
IHA (82 FR 49332; October 25, 2017) we estimated 811 takes of 
California sea lions would occur at Santa Cruz Island per boost-back 
and landing activity; however, since the notice of the proposed IHA was 
published, we have reviewed the sonic boom models presented in the IHA 
application and determined that a sonic boom of 1.0 psf or above is not 
expected to impact Santa Cruz Island, and therefore no takes of marine 
mammals on Santa Cruz Island are expected to occur as a result of the 
specified activities. Therefore, we do

[[Page 60963]]

not authorize any takes of California sea lions on Santa Cruz Island in 
this IHA. We authorize a total of 45,000 takes of California sea lions 
in this IHA (a total of 54,732 takes of California sea lions was 
proposed in the proposed IHA). We also note that in the Federal 
Register notice of the proposed IHA (82 FR 49332; October 25, 2017) we 
proposed to authorize a total of 1,384 takes of harbor seals. This was 
an error, as the number 1,384 represents the estimated number of takes 
of harbor seals per boost-back and landing activity. We intended to 
propose to authorize a total of 16,608 takes of harbor seals, which 
represents the number of estimated takes per boost-back and landing 
activity (1,384) times the number of activities (12). We therefore 
authorize a total of 16,608 takes of harbor seals in this IHA. These 
revisions in the take estimates have not changed any of our 
determinations.
    Given the many uncertainties in predicting the quantity and types 
of impacts of sound on marine mammals, it is common practice to 
estimate how many animals are likely to be present within a particular 
distance of a given activity, or exposed to a particular level of 
sound. In practice, depending on the amount of information available to 
characterize daily and seasonal movement and distribution of affected 
marine mammals, it can be difficult to distinguish between the number 
of individuals harassed and the instances of harassment and, when 
duration of the activity is considered, it can result in a take 
estimate that overestimates the number of individuals harassed. For 
instance, an individual animal may accrue a number of incidences of 
harassment over the duration of a project, as opposed to each incident 
of harassment accruing to a new individual. This is especially likely 
if individual animals display some degree of residency or site fidelity 
and the impetus to use the site is stronger than the deterrence 
presented by the harassing activity.
    Take estimates shown in Table 6 are considered reasonable estimates 
of the number of instances of marine mammal exposures to sound 
resulting in Level B harassment that are likely to occur as a result of 
the planned activities, and not necessarily the number of individual 
animals exposed.

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 impact on species or stocks and their 
habitat, as well as subsistence uses where applicable, we carefully 
balance 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--which considers the nature of the potential adverse 
impact being mitigated (likelihood, scope, range), as well as the 
likelihood that the measure will be effective if implemented; and the 
likelihood of effective implementation, 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.
    Any mitigation measure(s) prescribed by NMFS should be able to 
accomplish, have a reasonable likelihood of accomplishing (based on 
current science), or contribute to the accomplishment of one or more of 
the general goals listed below.
    1. Avoidance or minimization of injury or death of marine mammals 
wherever possible (goals 2, 3, and 4 may contribute to this goal).
    2. A reduction in the numbers of marine mammals (total number or 
number at biologically important time or location) exposed to 
activities expected to result in the take of marine mammals (this goal 
may contribute to 1, above, or to reducing harassment takes only).
    3. A reduction in the number of times (total number or number at 
biologically important time or location) individuals would be exposed 
to activities expected to result in the take of marine mammals (this 
goal may contribute to 1, above, or to reducing harassment takes only).
    4. A reduction in the intensity of exposures (either total number 
or number at biologically important time or location) to activities 
expected to result in the take of marine mammals (this goal may 
contribute to 1, above, or to reducing the severity of harassment takes 
only).
    5. Avoidance or minimization of adverse effects to marine mammal 
habitat, paying special attention to the food base, activities that 
block or limit passage to or from biologically important areas, 
permanent destruction of habitat, or temporary destruction/disturbance 
of habitat during a biologically important time.
    6. For monitoring directly related to mitigation--an increase in 
the probability of detecting marine mammals, thus allowing for more 
effective implementation of the mitigation.

Mitigation for Marine Mammals and Their Habitat

    SpaceX's IHA application contains descriptions of the mitigation 
measures proposed to be implemented during the specified activities in 
order to effect the least practicable adverse impact on the affected 
marine mammal species and stocks and their habitats.
    It should be noted that it would not be feasible to stop or divert 
an inbound Falcon 9 First Stage booster. Once the boost-back and 
landing sequence is underway, there would be no way for SpaceX to 
change the trajectory of the Falcon 9 First Stage to avoid potential 
impacts to marine mammals. The proposed mitigation measures include the 
following:
     Unless constrained by other factors including human safety 
or national security concerns, launches would be scheduled to avoid 
boost-backs and landings during the harbor seal pupping season of March 
through June, when practicable.
    Based on our evaluation of SpaceX's proposed mitigation measures, 
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

[[Page 60964]]

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 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.

Monitoring

    SpaceX submitted a monitoring plan as part of their IHA 
application. SpaceX's proposed marine mammal monitoring plan was 
created with input from NMFS and was based on similar plans that have 
been successfully implemented by other action proponents under previous 
authorizations for similar projects, specifically the USAF's monitoring 
of rocket launches from VAFB.

Marine Mammal Monitoring

    SpaceX will determine a monitoring location for each boost-back and 
landing activity, taking into consideration predictions of the areas 
likely to receive the greatest sonic boom intensity as well as current 
haulout locations and the distribution of pinniped species and their 
behavior. The selection of the monitoring location will also be based 
on what species (if any) have pups at haulouts and which of those 
species would be expected to be the most reactive to sonic booms. 
SpaceX prioritizes the selection of rookery locations if they are 
expected to be impacted by a sonic boom and prioritizes the most 
reactive species if there are multiple species that are expected to be 
hauled out in the modeled sonic boom impact area. For instance, if 
harbor seals were pupping, SpaceX will prioritize selection of a harbor 
seal rookery for monitoring because they tend to be the most reactive 
species to sonic booms. There is also thought given to the geography 
and wind exposure of the specific beaches that are predicted to be 
impacted, to avoid inadvertently selecting a portion of a beach that 
tends to be abandoned by pinnipeds every afternoon as a result high 
winds. As VAFB is an active military base, the selection of appropriate 
monitoring locations must also take into account security restrictions 
and human safety as unexploded ordnance is present in some areas
    Marine mammal monitoring protocols will vary based on modeled sonic 
boom intensity, the location and the season. As described above, sonic 
boom modeling will be performed prior to all boost-back and landing 
activities. Although the same rockets will be used, other parameters 
specific to each launch will be incorporated into each model. These 
include direction and trajectory, weight, length, engine thrust, engine 
plume drag, position versus time from initiating boost-back to 
additional engine burns, among other aspects. Various weather scenarios 
will be analyzed from NOAA weather records for the region, then run 
through the model. Among other factors, these will include the presence 
or absence of the jet stream, and if present, its direction, altitude 
and velocity. The type, altitude, and density of clouds will also be 
considered. From these data, the models will predict peak amplitudes 
and impact locations.
    As described above, impacts to pinnipeds on the NCI, including 
pups, have been shown through more than two decades of monitoring 
reports to be minimal and temporary (MMCG and SAIC 2012). Therefore 
monitoring requirements at the NCI will be dependent on modeled sonic 
boom intensity and will be based on the harbor seal pupping season, 
such that monitoring requirements are greater when pups are expected to 
be present. When pups are present at haulouts, a lower threshold is 
reasonable in that a sonic boom could theoretically pose a greater risk 
of abandonment of pups in the event that mothers flush to the water (we 
note, however, that pup abandonment has never been documented as a 
result of sonic booms at the NCI). As pups grow older and are more 
maneuverable, the risk of pup abandonment diminishes. Thus, at the 
height of the pupping season (between March 1 and June 30) monitoring 
is required if sonic boom model results indicate a peak overpressure of 
1.0 psf or greater is likely to impact one of the NCI. Between July 1 
and September 30 monitoring is required if sonic boom model results 
indicate a peak overpressure of 1.5 psf or greater is likely to impact 
one of the NCI. Between October 1 and February 28, monitoring is 
required if sonic boom model results indicate a peak overpressure of 
2.0 psf or greater is likely to impact one of the NCI.
    Marine mammal monitoring procedures will consist of the following:
     To conduct monitoring of Falcon 9 First Stage boost-back 
and landing activities, SpaceX will designate qualified (must be able 
to identify pinnipeds to species, age class, and sex when possible), 
on-site observers that will be approved in advance by NMFS;
     If sonic boom model results indicate a peak overpressure 
of 1.0 psf or greater is likely to impact VAFB, then acoustic and 
biological monitoring at VAFB will be implemented;
     If sonic boom model results indicate a peak overpressure 
of 1.0 psf or greater is likely to impact one of the NCI between March 
1 and June 30; a peak overpressure of greater than 1.5 psf is likely to 
impact one of the NCI between July 1 and September 30, or a peak 
overpressure of greater than 2.0 psf is likely to impact one of the NCI 
between October 1 and February 28, then monitoring of haulout sites on 
the NCI will be implemented. Monitoring will be conducted at the 
haulout site closest to the area predicted to experience the greatest 
sonic boom intensity, at both VAFB and the NCI. If multiple haulouts 
are located within the area expected to experience the greatest sonic 
boom intensity, selection of monitoring locations will be based on 
species (i.e., species known to be more

[[Page 60965]]

reactive to sonic booms will be prioritized) and pup presence (i.e., 
haulouts with pups will be prioritized);
     Monitoring will commence at least 72 hours prior to the 
boost-back and continue until at least 48 hours after the event;
     Monitors will conduct hourly counts for six hours per day 
centered around the scheduled launch time to the extent possible. 
Monitors will be at the monitoring location continuously for six hours 
per day and will record pinniped counts every hour during this period;
     If the activity occurs during daylight hours then the six 
hourly counts will be centered around the scheduled launch time (such 
that there are observations for 2-3 hours before and after the event). 
If the activity occurs during nighttime then hourly counts will 
commence at daybreak and proceed until six hours after daybreak (counts 
taken during nighttime are not accurate). Monitors would observe 
pinniped reactions with night vision binoculars for nighttime events;
     Monitoring will include multiple surveys each day that 
record the species; number of animals; general behavior; presence of 
pups; age class; gender; and reaction to noise associated with Falcon 9 
First Stage recovery activities, sonic booms or other natural or human 
caused disturbances, in addition to recording environmental conditions 
such as tide, wind speed, air temperature, and swell;
     If the boost-back and landing is scheduled during daylight 
hours, time lapse photography or video recording will be used to 
document the behavior of marine mammals during Falcon 9 First Stage 
recovery activities;
     For Falcon 9 First Stage recovery activities scheduled 
during harbor seal pupping season (March through June), follow-up 
surveys will be conducted within two weeks of the boost-back and 
landing;
     Newly documented northern elephant seal pupping locations 
at VAFB will be prioritized for monitoring when landings occur at SLC-
4W during northern elephant seal pupping season (January through 
February) when practicable.

Acoustic Monitoring

    Acoustic measurements of the sonic boom created during boost-back 
at the monitoring location will be recorded to determine the 
overpressure level. Typically this will entail use of a digital audio 
tape (DAT) recorder and a high quality microphone to monitor the sound 
environment and measure the sonic boom. This system will be specially 
tailored for recording the low frequency sound associated with rocket 
launches and sonic booms. The DAT system will record the launch noise 
and sonic boom digitally to tape, which will allow for detailed 
post[hyphen]analysis of the frequency content, and the calculation of 
other acoustic metrics, and will record the ambient noise and sonic 
boom. The DAT recorder will be placed near the marine mammal monitoring 
site when practicable.

Reporting

    SpaceX will report data collected during marine mammal monitoring 
and acoustic monitoring as described above. The monitoring report will 
include a description of project related activities, counts of marine 
mammals by species, sex and age class, a summary of marine mammal 
species/count data, and a summary of observed marine mammal responses 
to project-related activities.
    A launch monitoring report will be submitted by SpaceX to the NMFS 
Office of Protected Resources and the NMFS West Coast Region within 60 
days after each Falcon 9 First Stage recovery action. This report will 
contain information on the date(s) and time(s) of the Falcon 9 First 
Stage recovery action, the design of the monitoring program; and 
results of the monitoring program, including, but not necessarily 
limited to the following:
     Numbers of pinnipeds present on the monitored haulout 
prior to the Falcon 9 First Stage recovery;
     Numbers of pinnipeds that may have been harassed (based on 
observations of pinniped responses and the pinniped disturbance scale 
as shown in Table 4);
     The length of time pinnipeds remained off the haulout or 
rookery for pinnipeds estimated to have entered the water as a result 
of Falcon 9 First Stage recovery noise;
     Any other observed behavioral modifications by pinnipeds 
that were likely the result of Falcon 9 First Stage recovery 
activities, including sonic boom; and
     Results of acoustic monitoring including comparisons of 
modeled sonic booms with actual acoustic recordings of sonic booms.
    In addition, a final monitoring report will be submitted by SpaceX 
to the NMFS Office of Protected Resources. A draft of the report will 
be submitted within 90 days of the expiration of the IHA, or, within 45 
days of the requested renewal of the IHA (if applicable). A final 
version of the report will be submitted within 30 days following 
resolution of comments on the draft report from NMFS. The report will 
summarize the information from the 60-day post-activity reports (as 
described above), including but not necessarily limited to the 
following:
     Date(s) and time(s) of the Falcon 9 First Stage recovery 
actions;
     Design of the monitoring program; and
     Results of the monitoring program, including the 
information components contained in the 60-day launch reports, as well 
as any documented cumulative impacts on marine mammals as a result of 
the activities, such as long term reductions in the number of pinnipeds 
at haulouts as a result of the activities.
    In the unanticipated event that the specified activity clearly 
causes the take of a marine mammal in a manner not authorized by the 
IHA, such as a Level A harassment, or a take of a marine mammal species 
other than those authorized, SpaceX would immediately cease the 
specified activities and immediately report the incident to the NMFS 
Office of Protected Resources. The report would include the following 
information:
     Time, date, and location (latitude/longitude) of the 
incident;
     Description of the incident;
     Status of all Falcon 9 First Stage recovery activities in 
the 48 hours preceding the incident;
     Description of all marine mammal observations in the 48 
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 SpaceX to 
determine what is necessary to minimize the likelihood of further 
prohibited take and ensure MMPA compliance. SpaceX would not be able to 
resume their activities until notified by NMFS via letter, email, or 
telephone.
    In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead observer determines the cause of the injury or 
death is unknown and the death is relatively recent (i.e., in less than 
a moderate state of decomposition), SpaceX would immediately report the 
incident to mail to: The NMFS Office of Protected Resources and the 
NMFS West Coast Region Stranding Coordinator. The report would include 
the same information identified in the paragraph above. Authorized 
activities would be able to continue while NMFS reviews the 
circumstances of the incident. NMFS would work with SpaceX to determine 
whether

[[Page 60966]]

modifications in the activities are appropriate.
    In the event that SpaceX discovers an injured or dead marine 
mammal, and the lead MMO determines 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), SpaceX would report the incident 
to the NMFS Office of Protected Resources and NMFS West Coast Region 
Stranding Coordinator, within 24 hours of the discovery. SpaceX would 
provide photographs or video footage (if available) or other 
documentation of the stranded animal sighting to NMFS and the Marine 
Mammal Stranding Network.
    This will be the second IHA issued to SpaceX for the specified 
activity. SpaceX did not perform any Falcon 9 boost-back and landing 
activities that resulted in return flights to VAFB nor that generated 
sonic booms that impacted the NCI during the period of validity for the 
prior IHA issued for the same activity. SpaceX did perform boost-back 
and landing activities at a contingency landing location located 
offshore during the period of validity for the prior IHA, however the 
contingency landing location was located so far offshore that there 
were no impacts predicted to marine mammals by sonic boom modeling, 
thus marine mammal monitoring was not required.

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).
    To avoid repetition, the discussion of our analyses applies to all 
the species listed in Table 1, given that the anticipated effects of 
this activity on these different marine mammal species are expected to 
be similar. Activities associated with Falcon 9 First Stage recovery, 
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 B harassment (behavioral disturbance) only, 
from airborne sounds of sonic booms. Potential takes could occur if 
marine mammals are hauled out in areas where a sonic boom above 1.0 psf 
occurs, which is considered likely given the modeled sonic booms of the 
planned activities and the occurrence of pinnipeds in the project area. 
Based on the best available information, including monitoring reports 
from similar activities that have been authorized by NMFS, behavioral 
responses will likely be limited to reactions such as alerting to the 
noise, with some animals possibly moving toward or entering the water, 
depending on the species and the intensity of the sonic boom. Repeated 
exposures of individuals to levels of sound that may cause Level B 
harassment are unlikely to result in hearing impairment or to 
significantly disrupt foraging behavior. Thus, even repeated Level B 
harassment of some small subset of an overall stock is unlikely to 
result in any significant realized decrease in fitness to those 
individuals, and thus would not result in any adverse impact to the 
stock as a whole. Level B harassment would be reduced to the level of 
least practicable impact through use of mitigation measures described 
above.
    If a marine mammal responds to a stimulus by changing its behavior 
(e.g., through relatively minor changes in locomotion direction/speed), 
the response may or may not constitute taking at the individual level, 
and is unlikely to affect the stock or the species as a whole. However, 
if a sound source displaces marine mammals from an important feeding or 
breeding area for a prolonged period, impacts on animals or on the 
stock or species could potentially be significant (e.g., Lusseau and 
Bejder, 2007; Weilgart, 2007). Flushing of pinnipeds into the water has 
the potential to result in mother-pup separation, or could result in a 
stampede, either of which could potentially result in serious injury or 
mortality and thereby could potentially impact the stock or species. 
However, based on the best available information, including reports 
from over 20 years of launch monitoring at VAFB and the NCI, no serious 
injury or mortality of marine mammals is anticipated as a result of the 
planned activities.
    Even in the instances of pinnipeds being behaviorally disturbed by 
sonic booms from rocket launches at VAFB, no evidence has been 
presented of abnormal behavior, injuries or mortalities, or pup 
abandonment as a result of sonic booms (SAIC 2013). These findings came 
as a result of more than two decades of surveys at VAFB and the NCI 
(MMCG and SAIC, 2012). Post-launch monitoring generally reveals a 
return to normal behavioral patterns within minutes up to an hour or 
two of each launch, regardless of species. For instance, a total of 
eight Delta II and Taurus space vehicle launches occurred from north 
VAFB, near the Spur Road and Purisima Point haulout sites, from 
February, 2009 through February, 2014. Of these eight launches, three 
occurred during the harbor seal pupping season. The continued use by 
harbor seals of the Spur Road and Purisima Point haulout sites 
indicates that it is unlikely that these rocket launches (and 
associated sonic booms) resulted in long-term disturbances of pinnipeds 
using the haulout sites. San Miguel Island represents the most 
important pinniped rookery in the lower 48 states, and as such 
extensive research has been conducted there for decades. From this 
research, as well as stock assessment reports, it is clear that VAFB 
operations (including associated sonic booms) have not had any 
significant impacts on San Miguel Island rookeries and haulouts (SAIC 
2012).
    In summary, this negligible impact analysis is founded on the 
following factors:
     No injury, serious injury, or mortality are anticipated or 
authorized;
     The anticipated incidences of Level B harassment are 
expected to consist of, at worst, temporary modifications in behavior 
(i.e., short distance movements and occasional flushing into the water 
with return to haulouts within at most two days), which are not 
expected to adversely affect the fitness of any individuals;
     The activities are expected to result in no long-term 
changes in the use by

[[Page 60967]]

pinnipeds of rookeries and haulouts in the project area, based on over 
20 years of monitoring data; and
     The presumed efficacy of planned mitigation measures in 
reducing the effects of the specified activity to the level of least 
practicable impact.
    In combination, we believe that these factors, as well as the 
available body of evidence from other similar activities, demonstrate 
that the potential effects of the specified activity will be short-term 
on individual animals. The specified activity is not expected to impact 
rates of recruitment or survival and will therefore not result in 
population-level impacts. Based on the analysis contained herein of the 
likely effects of the specified activity on marine mammals and their 
habitat, and taking into consideration the implementation of the 
monitoring and mitigation measures, NMFS finds that the total marine 
mammal take from the planned activity will have a negligible impact on 
the 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, 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.
    The numbers of authorized takes would be considered small relative 
to the relevant stocks or populations (less than 22 percent for all 
species and stocks). It is important to note that the number of 
expected takes does not necessarily represent of the number of 
individual animals expected to be taken. Our small numbers analysis 
accounts for this fact. Multiple exposures to Level B harassment can 
accrue to the same individual animals over the course of an activity 
that occurs multiple times in the same area (such as SpaceX's planned 
activity). This is especially likely in the case of species that have 
limited ranges and that have site fidelity to a location within the 
project area, as is the case with harbor seals.
    As described above, harbor seals are non-migratory, rarely 
traveling more than 50 km from their haulout sites. Thus, while the 
estimated abundance of the California stock of Pacific harbor seals is 
30,968 (Carretta et al., 2017), a substantially smaller number of 
individual harbor seals is expected to occur within the project area. 
We expect that, because of harbor seals' documented site fidelity to 
haulout locations at VAFB and the NCI, and because of their limited 
ranges, the same individuals are likely to be taken repeatedly over the 
course of the specified activities (maximum of twelve Falcon 9 First 
Stage recovery actions). Therefore, the number of instances of Level B 
harassment among harbor seals over the course of the authorization 
(i.e., the total number of takes shown in Table 6) is expected to 
accrue to a much smaller number of individuals encompassing a small 
portion of the overall regional stock. The maximum number of individual 
of harbor seals expected to be taken by Level B harassment, per Falcon 
9 First Stage recovery action, is 1,384. As we believe the same 
individuals are likely to be taken repeatedly over the course of the 
specified activities, we use the estimate of 1,384 individual animals 
taken per Falcon 9 First Stage recovery activity for the purposes of 
estimating the percentage of the stock abundance likely to be taken 
over the course of the entire activity.
    Based on the analysis contained herein of the planned 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.

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 with respect to potential impacts 
on the human environment.
    This action is consistent with categories of activities identified 
in CE B4 of the Companion Manual for NAO 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 IHA qualifies to be categorically excluded from further 
NEPA review.

Endangered Species Act

    There is one marine mammal species (Guadalupe fur seal) listed 
under the ESA with confirmed occurrence in the area expected to be 
impacted by the planned activities. The NMFS West Coast Region has 
determined that NMFS OPR's issuance of the IHA to SpaceX for the take 
of marine mammals incidental to Falcon 9 First Stage recovery 
activities is not likely to adversely affect the Guadalupe fur seal. 
Therefore, formal ESA section 7 consultation on this IHA is not 
required.

Authorization

    NMFS has issued an IHA to SpaceX for the potential harassment of 
small numbers of six marine mammal species incidental to Falcon 9 First 
Stage recovery activities in California and at contingency landing 
locations offshore, provided the previously mentioned mitigation, 
monitoring and reporting requirements are incorporated.

    Dated: December 20, 2017.
Donna S. Wieting,
Director, Office of Protected Resources, National Marine Fisheries 
Service.
[FR Doc. 2017-27761 Filed 12-22-17; 8:45 am]
 BILLING CODE 3510-22-P