Endangered and Threatened Wildlife and Plants: Proposed Endangered Status for the Hawaiian Insular False Killer Whale Distinct Population Segment, 70169-70187 [2010-28843]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration

[Federal Register Volume 75, Number 221 (Wednesday, November 17, 2010)]
[Proposed Rules]
[Pages 70169-70187]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-28843]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Part 224

[Docket No. 0912161432-0453-02]
RIN 0648-XT37


Endangered and Threatened Wildlife and Plants: Proposed 
Endangered Status for the Hawaiian Insular False Killer Whale Distinct 
Population Segment

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

ACTION: Proposed rule; request for comments.

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SUMMARY: We, the NMFS, have completed a comprehensive status review of 
the Hawaiian insular false killer whale (Pseudorca crassidens) under 
the Endangered Species Act (ESA) in response to a petition submitted by 
the Natural Resources Defense Council (NRDC) to list the Hawaiian 
insular false killer whale as an endangered species. After reviewing 
the best scientific and commercial information available, we have 
determined that the Hawaiian insular false killer whale is a distinct 
population segment (DPS) that qualifies as a species under the ESA. 
Moreover, after evaluating threats facing the species, and considering 
efforts being made to protect the Hawaiian insular DPS, we have 
determined that the DPS is declining and is in danger of extinction 
throughout its range. We propose to list it as endangered under the 
ESA. Although we are not proposing to designate critical habitat at 
this time, we are soliciting information to inform the development of 
the final listing rule and designation of critical habitat in the event 
the DPS is listed.

DATES: Comments on this proposal must be received by February 15, 2011. 
A public hearing will be held on Oahu, Hawaii, on Thursday, January 20, 
2011, 6:30 p.m. to 9 p.m., at the McCoy Pavilion at Ala Moana Park, 
1201 Ala Moana Blvd., Honolulu, HI 96814. NMFS will consider requests 
for additional public hearings if any person so requests by January 31, 
2011. Notice of the location and time of any such additional hearing 
will be published in the Federal Register not less than 15 days before 
the hearing is held.

ADDRESSES: You may submit comments identified by 0648-XT37 by any one 
of the following methods:
     Electronic Submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal: https://www.regulations.gov. Follow the instructions for submitting comments.
     Mail or hand-delivery: Submit written comments to 
Regulatory Branch Chief, Protected Resources Division, National Marine 
Fisheries Service, Pacific Islands Regional Office, 1601 Kapiolani 
Blvd., Suite 1110, Honolulu, HI 96814, Attn: Hawaiian insular false 
killer whale proposed listing.
    Instructions: All comments received are a part of the public record 
and will generally be posted to https://www.regulations.gov without 
change. Comments will be posted for public viewing after the comment 
period has closed. All Personal Identifying Information (for example, 
name, address, etc.) voluntarily submitted by the commenter may be 
publicly accessible. Do not submit Confidential Business Information or 
otherwise sensitive or protected information. We will accept anonymous 
comments (enter ``N/A'' in the required fields if you wish to remain 
anonymous). Attachments to electronic comments will be accepted in 
Microsoft Word, Excel, WordPerfect, or Adobe PDF file formats only. The 
petition, status review report, and other reference materials regarding 
this determination can be obtained via the NMFS Pacific Islands 
Regional Office Web site: https://www.fpir.noaa.gov/PRD/prd_false_killer_whale.html or by submitting a request to the Regulatory Branch 
Chief, Protected Resources Division, National Marine Fisheries Service, 
Pacific Islands Regional Office, 1601 Kapiolani Blvd., Suite 1110, 
Honolulu, HI 96814, Attn: Hawaiian insular false killer whale proposed 
listing.

FOR FURTHER INFORMATION CONTACT: Krista Graham, NMFS, Pacific Islands 
Regional Office, 808-944-2238; Lance Smith, NMFS, Pacific Islands 
Regional Office, 808-944-2258; or Dwayne Meadows, NMFS, Office of 
Protected Resources, 301-713-1401.

SUPPLEMENTARY INFORMATION:

Background

    On October 1, 2009, we received a petition from the NRDC requesting 
that we list the insular population of Hawaiian false killer whales as 
an endangered species under the ESA and designate critical habitat 
concurrent with listing. According to the draft 2010 Stock Assessment 
Report (SAR) (Carretta et al., 2010) (available at https://www.nmfs.noaa.gov/pr/pdfs/sars/ sars/) that we have completed as required by 
the Marine Mammal Protection Act (MMPA), false killer whales within the 
United States (U.S.) Exclusive Economic Zone (EEZ) around the Hawaiian 
Islands are divided into a Hawaii pelagic stock and a Hawaii insular 
stock. The petition considers the insular population of Hawaiian false 
killer whales and the Hawaii insular stock of false killer whales to be 
synonymous. On January 5, 2010, we determined that the petitioned 
action presented substantial scientific and commercial information 
indicating that the petitioned action may be warranted, and we 
requested information to assist with a comprehensive status review of 
the species to determine if the Hawaiian insular false killer whale 
warranted listing under the Endangered Species Act of 1973 (ESA) (75 FR 
316).

ESA Statutory Provisions

    The ESA defines ``species'' to include subspecies or a DPS of any 
vertebrate species which interbreeds when mature (16 U.S.C. 1532(16)). 
The U.S. Fish and Wildlife Service (FWS) and NMFS have adopted a joint 
policy describing what

[[Page 70170]]

constitutes a DPS of a taxonomic species (61 FR 4722). The joint DPS 
policy identifies two criteria for making DPS determinations: (1) The 
population must be discrete in relation to the remainder of the taxon 
(species or subspecies) to which it belongs; and (2) the population 
must be significant to the remainder of the taxon to which it belongs.
    A population segment of a vertebrate species may be considered 
discrete if it satisfies either one of the following conditions: (1) 
``It is markedly separated from other populations of the same taxon as 
a consequence of physical, physiological, ecological, or behavioral 
factors. Quantitative measures of genetic or morphological 
discontinuity may provide evidence of this separation''; or (2) ``it is 
delimited by international governmental boundaries within which 
differences in control of exploitation, management of habitat, 
conservation status, or regulatory mechanisms exist that are 
significant in light of section 4(a)(1)(D)'' of the ESA.
    If a population segment is found to be discrete under one or both 
of the above conditions, its biological and ecological significance to 
the taxon to which it belongs is evaluated. Considerations under the 
significance criterion may include, but are not limited to: (1) 
``Persistence of the discrete population segment in an ecological 
setting unusual or unique for the taxon; (2) evidence that the loss of 
the discrete population segment would result in a significant gap in 
the range of a taxon; (3) evidence that the discrete population segment 
represents the only surviving natural occurrence of a taxon that may be 
more abundant elsewhere as an introduced population outside its 
historic range; and (4) evidence that the discrete population segment 
differs markedly from other populations of the species in its genetic 
characteristics.''
    The ESA defines an ``endangered species'' as one that is in danger 
of extinction throughout all or a significant portion of its range, and 
a ``threatened species'' as one that is likely to become an endangered 
species in the foreseeable future throughout all or a significant 
portion of its range (16 U.S.C. 1532 (6) and (20)). The statute 
requires us to determine whether any species is endangered or 
threatened because of any of the following factors: (1) The present or 
threatened destruction, modification, or curtailment of its habitat or 
range; (2) overexploitation for commercial, recreational, scientific, 
or educational purposes; (3) disease or predation; (4) the inadequacy 
of existing regulatory mechanisms; or (5) other natural or manmade 
factors affecting its continued existence (16 U.S.C. 1533). We are to 
make this determination based solely on the best available scientific 
and commercial information after conducting a review of the status of 
the species and taking into account any efforts being made by states or 
foreign governments to protect the species.
    When evaluating conservation efforts not yet implemented or 
implemented for only a short period of time to determine whether they 
are likely to negate the need to list the species, we use the criteria 
outlined in the joint NMFS and FWS Policy for Evaluating Conservation 
Efforts When Making Listing Decisions (PECE policy; 68 FR 15100).

Status Review and Approach of the BRT

    To conduct the comprehensive status review of the Hawaiian insular 
population of the false killer whale, we formed a Biological Review 
Team (BRT) comprised of eight federal scientists from our Northwest, 
Southwest, Alaska, and Pacific Islands Fisheries Science Centers. We 
asked the BRT to review the best available scientific and commercial 
information to determine whether the Hawaiian insular false killer 
whale warrants delineation into a DPS, using the criteria in the joint 
DPS policy. We asked the BRT to then assess the level of extinction 
risk facing the species at the DPS level, describing its confidence 
that the DPS is at high risk, medium risk, or low risk of extinction. 
The BRT defined the level of risk based on thresholds that have been 
used to assess other marine mammal species, and consistent with the 
criteria used by the International Union for the Conservation of Nature 
(IUCN) Red List of Threatened Species (IUCN, 2001). In evaluating the 
extinction risk, we asked the BRT to describe the threats facing the 
species, according to the statutory factors listed under section 
4(a)(1) of the ESA, and qualitatively assess the severity, geographic 
scope, and level of certainty of each threat (Oleson et al., 2010).
    In compiling the best available information, making a DPS 
determination, and evaluating the status of the DPS, the BRT considered 
a variety of scientific information from the literature, unpublished 
documents, and direct communications with researchers working on false 
killer whales, as well as technical information submitted to NMFS. The 
BRT formally reviewed all information not previously peer-reviewed, and 
only that information found to meet the standard of best available 
science was considered further. Analyses conducted by individual BRT 
members were subjected to independent peer review, as required by the 
Office of Management and Budget Peer Review and Bulletin and under the 
1994 joint NMFS/FWS peer review policy for ESA activities (59 FR 
34270), prior to incorporation into the status review report.
    The BRT acknowledged that considerable levels of uncertainty are 
present for all aspects of the Hawaiian insular false killer whale's 
biology, abundance, trends in abundance, and threats. Such 
uncertainties are expected for an uncommon species that is primarily 
found in the open ocean where research is expensive and knowledge is 
consequently poor. The BRT decided to treat the uncertainty explicitly 
by defining where it exists and using a point system to weigh various 
plausible scenarios, taking into account all of the best available data 
on false killer whales, but also considering information on other 
similar toothed whales. The BRT's objectives in taking this approach 
were to make the process of arriving at conclusions detailed in the 
status review report as transparent as possible and to provide 
assurance that the BRT was basing its conclusions on a common 
understanding of the evidence. Details of this approach can be found in 
Appendix A of the status review report.
    The report of the BRT deliberations (Oleson et al., 2010) 
(hereafter ``status review report'') thoroughly describes Hawaiian 
false killer whale biology, ecology, and habitat, provides input on the 
DPS determination, and assesses past, present, and future potential 
risk factors, and overall extinction risk. The key background 
information and findings of the status review report are summarized 
below.

Biology and Life History of False Killer Whales

    The following section presents biology and life history information 
gathered from throughout the range of false killer whales. A later 
section focuses on information specific to the Hawaiian insular false 
killer whale.

Description

    The false killer whale, Pseudorca crassidens (Owen, 1846) is a 
member of the family Delphinidae, and no subspecies have been 
identified. The species is a slender, large delphinid, with maximum 
reported sizes of 610 cm for males (Leatherwood and Reeves, 1983) and 
506 cm for females (Perrin and Reilly, 1984). Length at birth has been 
reported to range from 160-190 cm, and length at sexual maturity is 334 
through 427 cm in females and 396-457

[[Page 70171]]

cm in males (Stacey et al., 1994; Odell and McClune, 1999). Estimated 
age at sexual maturity is about 8 to 11 years for females, while males 
may mature 8 to 10 years later (Kasuya, 1986). The maximum reported age 
has been estimated as 63 years for females and 58 years for males 
(Kasuya, 1986), with females becoming reproductively senescent at about 
age 44 (Ferreira, 2008). Both sexes grow 40 to 50 percent in body 
length during their first year of life, but males subsequently grow 
faster than females. Growth ceases between 20 and 30 years of age, and 
there is evidence of geographic variation in final asymptotic body 
size. Off the coast of Japan, asymptotic length is 46 cm (females) and 
56 cm (males) longer than off the coast of South Africa (Ferreira, 
2008). Large individuals may weigh up to 1,400 kg. Coloration of the 
entire body is black or dark gray, although lighter areas may occur 
ventrally between the flippers or on the sides of the head. A 
prominent, falcate dorsal fin is located at about the midpoint of the 
back, and the tip can be pointed or rounded. The head lacks a distinct 
beak, and the melon tapers gradually from the area of the blowhole to a 
rounded tip. In males, the melon extends slightly further forward than 
in females. The pectoral fins have a unique shape among the cetaceans, 
with a distinct central hump creating an S-shaped leading edge.

Global Distribution and Density

    False killer whales are found in all tropical and warm-temperate 
oceans, generally in deep offshore waters, but also in some shallower 
semi-enclosed seas and gulfs (e.g., Sea of Japan, Yellow Sea, Persian 
Gulf), and near oceanic islands (e.g., Hawaii, Johnston Atoll, 
Galapagos, Guadeloupe, Martinique) (Leatherwood et al., 1989). 
Sightings have also been reported as ``common'' in Brazilian shelf 
waters (IWC, 2007) where animals could be seen from shore from Rio de 
Janeiro feeding in an upwelling zone that concentrates prey. There are 
occasional records in both the northern and southern hemispheres of 
animals at latitudes as high as about 50 degrees (Stacey and Baird, 
1991; Stacey et al., 1994). In the western Pacific off the coast of 
Japan, false killer whales appear to move north-south seasonally, 
presumably related to prey distribution (Kasuya, 1971), but seasonal 
movements have not been documented elsewhere. Densities in the central 
and eastern Pacific range from 0.02 to 0.38 animals per 100 km\2\ (Wade 
and Gerrodette, 1993; Mobley et al., 2000; Ferguson and Barlow, 2003; 
Carretta et al., 2007), with the lowest densities reported for waters 
north of about 15 degrees north off Baja California, Mexico, and within 
the U.S. EEZ around Hawaii, and highest densities reported in waters 
surrounding Palmyra Atoll. Unlike other species that can be found both 
along continental margins and in offshore pelagic waters (e.g., 
bottlenose dolphins (Tursiops truncatus)), false killer whale densities 
generally do not appear to increase closer to coastlines.
    Although false killer whales are found globally, genetic, 
morphometric, and life history differences indicate there are distinct 
regional populations (Kitchener et al., 1990; Mobley et al., 2000; 
Chivers et al., 2007; Ferreira, 2008). Within waters of the central 
Pacific, four Pacific Islands Region management stocks of false killer 
whales are currently recognized for management under the U.S. MMPA: The 
Hawaii insular stock, the Hawaii pelagic stock, the Palmyra Atoll 
stock, and the American Samoa stock (Carretta et al., 2010).

Life History

    False killer whales are long-lived social odontocetes. Much of what 
is known about their life history comes either from examination of dead 
animals originating from drive fisheries in Japan (Kasuya and Marsh, 
1984; Kasuya, 1986) or strandings (Purves and Pilleri, 1978; Ferreira, 
2008). The social system has been described as matrilineal (Ferreira, 
2008). However, this is not consistent with two known characteristics 
of false killer whales: Males leave their natal group when they begin 
to become sexually mature; and research showing females within a single 
group have different haplotypes, indicating that even among females, 
groups are composed of more than near-relatives (Chivers et al., 2010). 
Ferreira (2008) suggested the mating system may be polygynous based on 
the large testes size of males, but actual understanding of the mating 
system remains poor.
    The only reported data on birth interval, 6.9 years between calves, 
is from Japan (Kasuya, 1986). However, annual pregnancy rates were 
reported for Japan as 11.4 percent and 2.2 percent for South Africa 
(Ferreira, 2008). A rough interbirth interval can be calculated by 
taking the inverse of the annual pregnancy rate, which yields intervals 
of 8.8 and 45 years for Japan and South Africa, respectively. A single 
stranding group where 1 out of 37 adult females was pregnant was the 
source of the South African data, which may not be a representative 
sample and could be insufficient to estimate pregnancy rates in that 
population.
    Comparisons of the life history parameters inferred from the 
Japanese drive fishery samples and the South African stranding sample 
indicated that the whales in Japan attained a larger asymptotic body 
size and grew faster. Also, a suite of characteristics of the whales in 
Japan indicated a higher reproductive rate: The ratio of reproductive 
to post-reproductive females was higher and the pregnancy rate was 
higher than in South Africa. Possible reasons given by Ferreira (2008) 
for the apparently higher reproductive rate in Japan are: The Japan 
whales are exhibiting a density-dependent response to population 
reduction as a result of exploitation; the colder waters near Japan are 
more productive; or differences in food quality. The estimated 
reproductive rates in both Japan and South Africa are low compared to 
those of other delphinids and especially to the two species with the 
most similar life history: Short-finned pilot whales (Globicephala 
macrorhynchus), and Southern Resident killer whales (Orcinus orca) 
(Olesiuk et al., 1990).
    Little is known about the breeding behavior of false killer whales 
in the wild, but some information is available from false killer whales 
held in oceanaria (Brown et al., 1966). Gestation has been estimated to 
last 11 to 16 months, (Kasuya, 1986; Odell and McClune, 1999). Females 
with calves lactate for 18 to 24 months (Perrin and Reilly, 1984). In 
captive settings, false killer whales have mated with other delphinids, 
including short-finned pilot whales and bottlenose dolphins. Bottlenose 
dolphins in captivity have produced viable offspring with false killer 
whales (Odell and McClune, 1999).
    Reproductive senescence is quite rare in cetaceans but has been 
documented in false killer whales and other social odontocetes. The two 
primary reasons given for reproductive senescence are increasing 
survival of offspring as a result of care given by multiple females of 
multiple generations (grandmothering), and transmission of learning 
across generations allowing survival in lean periods by remembering 
alternative feeding areas or strategies (McAuliffe and Whitehead, 2005; 
Ferreira, 2008).
    Wade and Reeves (2010) argue that odontocetes have delayed recovery 
as compared to mysticetes when numbers are reduced because of the 
combination of their life history, which results in exceptionally low 
maximum population growth rates, and the potential for social 
disruption. Particularly if older females are lost, it may take decades 
to rebuild the knowledge required to achieve maximum population growth 
rates.

[[Page 70172]]

Wade and Reeves (2010) give numerous examples, both from cetaceans 
(beluga whales (Delphinapterus leucas), killer whales, and sperm whales 
(Physeter macrocephalus) are particularly pertinent) and elephants, 
which are similarly long-lived social animals with reproductive 
senescence.

Feeding Ecology

    False killer whales are top predators, eating primarily fish and 
squid, but also occasionally taking marine mammals (see references in 
Oleson et al., 2010). These conclusions are based on relatively limited 
data from various parts of the species' range.The large, widely spread 
groups in which false killer whales typically occur (Baird et al., 
2008a; Baird et al., 2010) and their patchily distributed prey suggest 
that this species forages cooperatively. Further evidence for the 
social nature of false killer whale foraging is the observation of prey 
sharing among individuals in the group (Connor and Norris, 1982; Baird 
et al., 2008a). False killer whales feed both during the day and at 
night (Evans and Awbrey, 1986; Baird et al., 2008a).

Diving Behavior

    Limited information is available on the diving behavior of false 
killer whales. Maximum dive depth was estimated at 500 m (Cummings and 
Fish, 1971). Time depth recorders have been deployed on four false 
killer whales (R. Baird, pers. comm., Cascadia Research Collective) 
totaling approximately 44 hours. The deepest dive recorded during a 22-
hour deployment was estimated to have been as deep as 700 m (estimate 
based on duration past the recorder's 234 m limit and ascent and 
descent rates). However, only 7 dives were to depths greater than 150 
m, all of them accomplished in the daytime. Nighttime dives were all 
shallow (30-40 m maximum), but relatively lengthy (approximately 6-7 
minutes).
    Indirect evidence of dive depths by false killer whales can be 
inferred from prey. Mahimahi has been noted as a prominent prey item 
(Baird, 2009). Based on the catch rates of longlines instrumented with 
depth sensors and capture timers (Boggs, 1992) in the daytime, mahimahi 
are caught closer to the surface than other longline-caught fish, 
primarily in the upper 100 m. Other prey species, such as bigeye tuna, 
typically occur much deeper, from the surface down to at least 400 m 
(Boggs, 1992). The deepest dives by the instrumented false killer 
whales approach the daytime swimming depth limit of swordfish (Xiphias 
gladius), a prey item, near 700 m (Carey and Robinson, 1981).

Social Behavior

    There is quite a bit of variance in estimates of group size of 
false killer whales. At least some of the variability stems from 
estimation methods and time spent making the group size estimate. Most 
group sizes estimated from boats or planes vary from 1 to over 50 
animals with an average from 20 to 30, and group size estimates 
increase with encounter duration up to 2 hours (Baird et al., 2008a). 
Group size tends to increase with encounter duration because the 
species often occurs in small subgroups that are spread over tens of 
square miles. It is possible that the groups seen on typical boat or 
plane surveys are only part of a larger group spread over many miles 
(see e.g., Baird et al., 2010) that are in acoustic contact with one 
another. These widespread aggregations of small groups can total 
hundreds of individuals (Wade and Gerrodette, 1993; Carretta et al., 
2007; Baird, 2009; Reeves et al., 2009). Mass strandings of large 
groups of false killer whales (range 50-835; mean = 180) have been 
documented in many regions, including New Zealand, Australia, South 
Africa, the eastern and western North Atlantic, and Argentina (Ross, 
1984). Groups of 2-201 individuals (mean = 99) have also been driven 
ashore in Japanese drive fisheries (Kasuya, 1986). The social 
organization of smaller groups has been studied most extensively near 
the main Hawaiian Islands (Baird et al., 2008a), where individuals are 
known to form strong long-term bonds. False killer whales are also 
known to associate with other cetacean species, especially bottlenose 
dolphins (Leatherwood et al., 1988). Interestingly, records also show 
false killer whales attacking other cetaceans, including sperm whales 
and bottlenose dolphins (Palacios and Mate, 1996; Acevedo-Gutierrez et 
al., 1997).

Biology and Life History of Hawaiian Insular False Killer Whales

Current Distribution

    The boundaries of Hawaiian insular false killer whale distribution 
have been assessed using ship and aerial survey sightings and location 
data from satellite-linked telemetry tags. Satellite telemetry location 
data from seven groups of individuals tagged off the islands of Hawaii 
and Oahu indicate that the whales move widely and quickly among the 
main Hawaiian Islands and use waters up to at least 112 km offshore 
(Baird et al., 2010; Forney et al., 2010). Regular movement throughout 
the main Hawaiian Islands was also documented by re-sightings of 
photographically-identified individuals over several years (Baird et 
al., 2005; Baird, 2009; Baird et al., 2010). Individuals use both 
windward and leeward waters, moving from the windward to leeward side 
and back within a day (Baird, 2009; Baird et al., 2010; Forney et al., 
2010). Some individual false killer whales tagged off the Island of 
Hawaii have remained around that island for extended periods (days to 
weeks), but individuals from all tagged groups eventually ranged widely 
throughout the main Hawaiian Islands, including movements to the west 
of Kauai and Niihau (Baird, 2009; Forney et al., 2010). Based on 
locations obtained from 20 satellite-tagged insular false killer 
whales, the minimum convex polygon range for the insular population was 
estimated to encompass 77,600 km\2\ (M.B. Hanson, unpublished data).
    The greatest offshore movements occurred on the leeward sides of 
the islands, although on average, similar water depths and habitat were 
utilized on both the windward and leeward sides of all islands (Baird 
et al., 2010). Individuals utilize habitat overlaying a broad range of 
water depths, varying from shallow (<50 m) to very deep (>4,000 m) 
(Baird et al., 2010). Tagged insular false killer whales have often 
demonstrated short- to medium-term residence in individual island areas 
before ranging widely among islands and adopting another short-term 
residency pattern. It is likely that movement and residency patterns of 
the whales vary over time depending on the density and movement 
patterns of their prey species (Baird, 2009).
    A genetically distinct population of pelagic false killer whales 
occurs off Hawaii (Chivers et al., 2007). Hawaiian insular false killer 
whales share a portion of their range with the genetically distinct 
pelagic population (Forney et al., 2010). Satellite telemetry locations 
from a single tagged individual from the pelagic population, as well as 
shipboard and small boat survey sightings, suggest that the ranges of 
the two populations overlap in the area between 42 km and 112 km from 
shore (Baird et al., 2010; Forney et al., 2010). Based on this 
evidence, it is clear that the region from about 40 km to at least 112 
km from the main Hawaiian Islands is an overlap zone, in which both 
insular and pelagic false killer whales can be found. However, a small 
sample size of satellite-tracked individuals creates some uncertainty 
in these boundaries. In particular, the offshore boundary of the 
insular stock is

[[Page 70173]]

likely to be farther than 112 km because their documented offshore 
extent has increased as sample sizes of satellite-tracked individuals 
have increased. It is likely that additional deployments in the future 
will continue to result in greater maximum documented distances for 
insular false killer whales. Thus, an additional geographic ``buffer'' 
beyond the present maximum distance of 112 km has been recognized out 
to 140 km. Moreover, 140 km is approximately 75 nmi which follows the 
original boundary recommendation of Chivers et al. (2008). Therefore, 
the draft 2010 SAR for false killer whales recognizes an overlap zone 
between insular and pelagic false killer whales between 40 km and 140 
km from the main Hawaiian Islands based on sighting, telemetry, and 
genetic data (based on justification in Forney et al., 2010; Carretta 
et al., 2010). We recognize that boundary for this status review as 
well.

Life History

    There is no information available to assess whether the life 
history of Hawaiian insular false killer whales differs markedly from 
other false killer whale populations. However, there is also no 
evidence to show they are similar. As discussed earlier, false killer 
whales in Japan were larger and had a higher reproductive output than 
those in South Africa, and these differences were attributed to one or 
more of the following: colder more productive waters, response to 
exploitation, and different food in the two regions (Ferreira, 2008). 
It remains uncertain whether Hawaiian insular false killer whales are 
more like those from Japan or those from South Africa.

Social Structure

    Molecular genetic results support the separation of Hawaiian 
insular false killer whales from the more broadly distributed Hawaiian 
pelagic false killer whales (Chivers et al., 2007; 2010). Matches from 
photo-identification of individuals in groups of insular false killer 
whales also suggests functional isolation of the insular population 
from the overlapping pelagic population of false killer whales (Baird 
et al., 2008a). Based on 553 identifications available as of July 2009, 
with the exception of observations of four small groups (two observed 
near Kauai and two off the Island of Hawaii), all false killer whales 
observed within 40 km of the main Hawaiian Islands link to each other 
through a single large social network that makes up the insular 
population. A large group of 19 identified individuals of the pelagic 
population (or presumed to be) seen 42 km from shore and 
identifications from a number of other sightings of smaller groups do 
not link into the social network (Baird, 2009).
    The social cohesion of insular false killer whales is likely 
important to maintaining high fecundity and survival as it is in other 
highly social animals. Although some aspects of the behavior and 
``culture'' of Hawaiian insular false killer whales have been 
investigated or discussed, the mechanisms by which they might influence 
population growth rates are not well understood. The situation of this 
population could be analogous to those of other populations of large 
mammals in which females live well beyond their reproductive life spans 
(e.g., elephants, higher primates, and some other toothed cetaceans 
such as pilot whales) (McComb et al., 2001; Lahdenpera et al., 2004). 
The loss of only a few key individuals--such as the older, post-
reproductive females--could result in a significant loss of inclusive 
fitness conveyed by ``grandmothering'' behavior (i.e., assistance in 
care of the young of other females in the pod). In addition, cultural 
knowledge (e.g., how to cope with environmental changes occurring on 
decadal scales) could be lost, leading to reduced survival or fecundity 
of some or all age classes. Wade and Reeves (2010) document the special 
vulnerability of social odontocetes giving examples of killer whales, 
belugas, sperm whales, and dolphins in the eastern tropical Pacific.

Historical Population Size

    Historical population size is unknown. BRT members used density 
estimates from other areas together with the range inferred from 
telemetry data (see above) to suggest plausible ranges for historical 
abundance. Using the estimated density of false killer whales around 
the Palmyra Atoll EEZ, 0.38 animals/100 km\2\, where the highest 
density of this species has been reported (Barlow and Rankin, 2007), 
and extrapolating that density out to the 202,000 km\2\ area within 140 
km of the main Hawaiian Islands (proposed as a stock boundary for 
Hawaiian insular false killer whales in the draft 2010 SAR), a point-
estimate, or a plausible historical abundance, for the insular 
population is around 769. Alternatively, using one standard deviation 
above the point-estimate of the density around Palmyra Atoll to account 
for uncertainty in that density estimate, the upper limit of the 
abundance of Hawaiian insular false killer whales could have reached 
1,392 animals. The BRT placed the lower limit of plausible population 
size in 1989 at 470 based on the estimated number of animals observed 
in the 1989 aerial surveys (see above).
    There are several important caveats. Even though Palmyra has a 
density that is high relative to other areas, it is unlikely that this 
represented a pristine population during the 2005 survey on which the 
estimate is based. Given the depredation tendencies of false killer 
whales, known long-lining in the Palmyra area, and the fact that false 
killer whales are known to become seriously injured or die as a result 
of interactions with longlines, the possibility that current densities 
are lower than historical densities cannot be discounted. Although 
Palmyra is situated in more productive waters than the Hawaiian 
Islands, we do not understand enough about the feeding ecology, 
behavior, and social system(s) of false killer whales to know how or 
whether productivity might be related to animal density for false 
killer whales. This caveat is true for all other areas where population 
density estimates exist for false killer whales. Therefore, we used and 
view data from Palmyra as a conservative estimate of pristine density.

Current Abundance

    The draft 2010 SAR for Hawaiian insular false killer whales 
(Carretta et al., 2010) gives the best estimate of current population 
size as 123 individuals (coefficient of variation, or CV = 0.72), 
citing Baird et al. (2005). Recent reanalysis of photographic data has 
yielded two new estimates of population size for the 2006-2009 period. 
Two estimates are presented because two groups photographed near Kauai 
have not yet been observed to associate into the social network of 
false killer whales seen at the other islands. These animals may come 
from the pelagic population, may come from another undocumented 
population in the Northwestern Hawaiian Islands, or may represent a 
portion of the insular population that has not been previously 
documented photographically. The current best estimates of population 
size for Hawaiian insular false killer whales are 151 individuals (CV = 
0.20) without the animals photographed at Kauai, or 170 individuals (CV 
= 0.21) with them. As a comparison, the Hawaiian pelagic population is 
estimated to be 484 individuals (CV = 0.93) within the U.S. EEZ 
surrounding Hawaii (Barlow and Rankin, 2007).
    Although the absolute abundance of Hawaiian insular false killer 
whales is small, the core-area (within 40 km) population density (0.12 
animals/100 km\2\) is among the highest reported for this species. The 
high density of the Hawaiian insular population suggests a unique 
habitat capable of supporting a

[[Page 70174]]

larger population density than nearby oligotrophic waters.

Trends in Abundance

    Aerial survey sightings since 1989 suggest that the Hawaiian 
insular false killer whale population has declined over the last 2 
decades. A survey was conducted in June and July 1989 on the leeward 
sides of Hawaii, Lanai, and Oahu to determine the minimum population 
size of false killer whales in Hawaiian waters. False killer whales 
were observed on 14 occasions with 3 large groups (group sizes of 470, 
460, and 380) reported close to shore off the Island of Hawaii on 3 
different days (Reeves et al., 2009). As described in the Current 
Abundance section, the current best estimates of population size for 
Hawaiian insular false killer whales are 151 individuals without the 
animals photographed at Kauai, or 170 with them. Therefore, the largest 
group seen in 1989 is much larger than the current best estimate of the 
size of the insular population. Although the animals seen during the 
1989 surveys are assumed to come from the insular population based on 
their sighting location within 55 km of the Island of Hawaii, it is 
possible that they represent a short-term influx of pelagic animals to 
waters closer to the islands. Moreover, because photographic or genetic 
identification of individuals is often required to determine the 
population identity of false killer whales in Hawaiian waters, we 
cannot be absolutely certain that sightings from the 1989 or 1993 to 
2003 aerial surveys came from the insular population. Similarly, false 
killer whale bycatch or sightings by observers aboard fishing vessels 
cannot be attributed to the insular population when no identification 
photographs or genetic samples are obtained. Nevertheless, because of 
the location of the sightings and lack of evidence of pelagic animals 
occurring that close to the islands, it is most likely that this group 
did consist of insular animals.
    With respect to trends in group size, the average group size during 
the 1989 survey (195 animals) is larger than the typical average group 
size for the insular population (25 animals for encounters longer than 
2 hours) during more recent surveys (Baird et al., 2005). The 1989 
average group size is also larger than the more recent average of that 
observed for the pelagic population (12 animals) (Barlow and Rankin, 
2007).
    Five additional systematic aerial surveys were conducted between 
1993 and 2003 covering both windward and leeward sides of all of the 
main Hawaiian Islands, including channels between the islands, out to a 
maximum distance of about 46 km from shore (Mobley et al., 2000; 
Mobley, 2004). A regression of sighting rates from these surveys 
suggests a significant decline in the population size (Baird, 2009). 
The large groups sizes observed in 1989, together with the declining 
encounter rates from 1993 through 2003 suggest that Hawaiian insular 
false killer whales have declined substantially in recent decades.
    It is possible that weather or other survey conditions are at least 
partially responsible for the decline in sighting rates from 1993 
through 2003; however, there was no downward trend in the sighting 
rates for the four most commonly seen species of small cetaceans 
(spinner dolphin (Stenella longirostris), bottlenose dolphin, spotted 
dolphin (Stenella attenuata), and short-finned pilot whale). These four 
species represent nearshore and pelagic habitat preferences and span a 
range of body sizes from smaller to larger than false killer whales. It 
can be inferred from this evidence that variability in sighting 
conditions during the survey period did not have a major effect on 
sighting rates and therefore the sighting rate for insular false killer 
whales has, in fact, declined.
    A number of additional lines of evidence, summarized in Baird 
(2009), support a recent decline in Hawaiian insular false killer whale 
population size. Individual researchers in Hawaii have noted a marked 
decline in encounter rates since the 1980s and the relative encounter 
rate of false killer whales during the 1989 aerial survey was much 
higher than current encounter rates.

Population Structure

    Chivers et al. (2007) delineated false killer whales around Hawaii 
into two separate populations: Hawaiian insular and Hawaiian pelagic. 
That work has recently been extended with new samples, the addition of 
nuclear markers, and an analysis with a broader interpretation of the 
data (Chivers et al., 2010). The new analysis examined mitochondrial 
DNA (mtDNA) using sequences of 947 base pairs from the d-loop and 
nuclear DNA (nDNA) using eight microsatellites. These additional 
samples help confirm the delineation of these two populations.
    Three stratifications of the mtDNA data examined genetic 
differentiation at different spatial scales (Chivers et al., 2010). The 
broad-scale stratification recognized three groups: Hawaiian insular, 
central North Pacific, and eastern North Pacific. In the fine-scale 
stratification, five strata were recognized: Hawaiian insular, Hawaiian 
pelagic, Mexico, Panama, and American Samoa. The finest-scale 
stratification recognized each of the main Hawaiian Islands as strata.
    All but one Hawaiian insular false killer whale had one of two 
closely related haplotypes that have not been found elsewhere. The 
presence of two distinct, closely related haplotypes in Hawaiian 
insular false killer whales is consistent with Hawaiian insular false 
killer whales having little gene flow from other areas. This pattern 
differs from those of Hawaiian stocks of bottlenose, spinner, and 
spotted dolphins that all have evidence suggesting multiple successful 
immigration events. The pattern of primarily closely related haplotypes 
shown in Hawaiian insular false killer whales is consistent with a 
strong social system or strong habitat specialization that makes 
survival of immigrants or their offspring unlikely. One single 
individual, a male, was found in among Hawaiian insular false killer 
whales with a different haplotype. Although there is no photograph of 
that male to connect it directly to Hawaiian insular false killer 
whales, it was sampled within a group with such strong connections that 
assignment tests could not exclude that it belongs to the insular 
group. Given the low power of the current assignment test (with few 
microsatellite markers), the possibility of immigration (permanent 
membership with Hawaiian insular false killer whales but with an origin 
outside the group) cannot be ruled out. Likewise, the possibility that 
this individual was a temporary visitor (i.e., not a true immigrant) 
from the pelagic population cannot be excluded. The rare haplotype is 
sufficiently distantly related that it seems most plausible that this 
resulted from a separate immigration event (i.e., that immigrants are 
accepted on rare occasions).
    The mtDNA data also show strong differentiation between Hawaiian 
insular false killer whales (n = 81) and both broad-scale strata 
(central North Pacific (n = 13) and eastern North Pacific (n = 39)) and 
fine-scale strata (Hawaiian pelagic (n = 9), Mexico (n = 19), Panama (n 
= 15), and American Samoa (n = 6)). Genetic divergence between the 
Hawaiian insular false killer whales and other strata examined showed 
magnitudes of differentiation that were all consistent with less than 
one migrant per generation. No significant differences were found among 
the main Hawaiian Islands with sufficient data for statistical analysis 
(Hawaii, Oahu, and Maui).
    Nuclear DNA results also showed highly significant differentiation 
among

[[Page 70175]]

the broad and fine strata (Hawaiian insular (n = 69), central North 
Pacific (n = 13), eastern North Pacific (n = 36), Hawaiian pelagic (n = 
9), Mexico (n = 19), Panama (n = 12), and American Samoa (n = 6)). The 
estimates of divergence between the Hawaiian insular strata and other 
strata demonstrate that the magnitude of differentiation was less for 
nDNA than for mtDNA, indicating the potential for some male-mediated 
gene flow. Tests for differences between currently living males and 
females in level of differentiation were not significant for either 
mtDNA or nDNA. However, this test has no ability to detect differences 
in male versus female gene flow in the past. Chivers et al. (2010) give 
a number of hypotheses for the apparently different magnitude of 
signals between mtDNA and nDNA: (1) There is a low level of male-
mediated gene flow that was not apparent because of insufficient 
sampling of nearby groups of false killer whales and/or the test for 
male-mediated gene flow can only detect first-generation male migrants; 
(2) the magnitude of nDNA differentiation is underestimated because of 
the high mutation rate of microsatellites; or (3) the magnitude of 
differentiation is not inconsistent with cases where selection has been 
shown to be strong enough for local adaptation.
    The aforementioned uncertainties will best be resolved with 
additional sampling of nearby pelagic waters. Although the sample 
distribution is improved since the 2007 analysis, it remains poor in 
pelagic areas. The only full-scale cetacean survey of Hawaiian pelagic 
waters resulted in only two sightings of false killer whales in four 
months of effort, and the weather was too poor to obtain any high-
quality identification photographs or biopsies (J. Barlow, pers. comm., 
NMFS SWFSC). Fisheries observers are trained to obtain identification 
photographs and biopsy samples; however, conditions during 
disentanglement usually result in photographs difficult to identify due 
to darkness, and prevent successful biopsy.
    The strongest data with which to evaluate population structure are 
the mtDNA data. Approximately half of the population of Hawaiian 
insular false killer whales has been sampled, and all but one 
individual has one of two closely related haplotypes that have not been 
found elsewhere.
    Chivers et al. (2010) used the analytical method of Piry et al. 
(1999) to test for evidence of a recent decline in abundance within the 
Hawaiian insular population. The analysis takes advantage of the fact 
that when the effective size of a population is reduced, the allelic 
diversity of the population is reduced more rapidly than its 
heterozygosity, resulting in an apparent excess of heterozygosity given 
the number of alleles detected. Chivers et al. (2010) detected 
statistically significant evidence of a recent decline in Hawaiian 
insular false killer whales using this method, with all eight 
microsatellite loci exhibiting heterozygosity excess.
    The microsatellite data were also used to estimate the effective 
population size of Hawaiian insular false killer whales as 46 (95 
percent CI = 32-69). Because this population may have recently declined 
and the animals are long-lived, many of those individuals still alive 
likely were born prior to the decline. Thus, the estimate of effective 
population size is likely too high. Nevertheless, domestic animals have 
been shown to start displaying deleterious genetic effects (lethal or 
semi-lethal traits) when effective population size reaches about 50 
individuals (Franklin, 1980). While negative genetic effects cannot be 
predicted for a group of individuals that are probably naturally 
uncommon with a strong social structure that limits genetic diversity, 
the current low effective population size is a concern.

DPS Determination

    We have determined that Hawaiian insular false killer whales are 
discrete from other false killer whales based on genetic discontinuity 
and behavioral factors (the uniqueness of their behavior related to 
habitat use patterns). We have also determined that Hawaiian insular 
false killer whales are significant to the taxon, based on their unique 
ecological setting, marked genetic characteristic differences, and 
cultural factors.
    Both mitochondrial DNA (mtDNA) and nuclear DNA (nDNA) provide 
support for genetic discontinuity. As explained in the Population 
Structure section of this proposed rule, genetic differentiation was 
examined at different spatial scales. The mtDNA data show strong 
differentiation between Hawaiian insular false killer whales and other 
false killer whale groups at both broad-scale strata (central North 
Pacific and eastern North Pacific) and fine-scale strata (Hawaiian 
pelagic, Mexico, Panama, and American Samoa). The strongest DNA data 
come from mtDNA. The Hawaiian insular false killer whales have 
approximately half of the population sampled, and all but one 
individual has one of the two closely related haplotypes that have not 
been found elsewhere. The BRT concluded that this pattern alone argues 
for a strong possibility of a high degree of separation. Nuclear DNA 
(microsatellite) data are also consistent with little gene flow between 
Hawaiian insular false killer whales and other false killer whales and 
support discreteness. Nuclear DNA results showed highly significant 
differentiation among the Hawaiian insular, North Pacific, eastern 
North Pacific, Hawaiian pelagic, Mexico, Panama, and American Samoa 
strata.
    Hawaiian insular false killer whales are behaviorally unique 
because they are the only population of the species known to have 
movements restricted to the vicinity of an oceanic island group. This 
behavioral separation is supported by their linkage through a tight 
social network, without any linkages to animals outside of the Hawaiian 
Islands. Phylogeographic analysis also indicates an isolated population 
with nearly exclusive haplotypes, and telemetry data show that all 20 
satellite-linked telemetry tagged Hawaiian insular false killer whales 
remained within the main Hawaiian Islands (Baird et al., 2010; Baird et 
al., unpublished data), in contrast with a single tagged pelagic false 
killer whale, which ranged far from shore. Although it is not unusual 
for false killer whales to be observed close to land, long-term history 
of exclusive use of a specific mainland or island system has not been 
documented elsewhere.
    Hawaiian insular false killer whales are significant to the taxon 
based on persistence in a unique ecological setting, marked genetic 
characteristic differences, and cultural factors. Hawaiian insular 
false killer whales persist in an ecological setting unusual or unique 
from other false killer whale populations because they are found 
primarily in island-associated waters that are relatively shallow and 
productive compared to surrounding oligotrophic waters. The following 
lines of evidence supporting this unique ecological setting include: 
Utilization of prey associated with island habitat that may require 
specialized knowledge of locations and seasonal conditions that 
aggregate prey or make them more vulnerable to predation. In an insular 
habitat, such foraging grounds may occur more regularly or in more 
predictable locations than on the high seas. The contaminant levels 
found in insular animals also suggest that both insular false killer 
whales and their prey may be associated with the urban island 
environment. And despite their small population size, the density 
(animals per km\2\) of Hawaiian insular false killer whales is high 
relative to other false killer whale populations, suggesting the

[[Page 70176]]

nearshore habitat or a unique habitat-use strategy may support a higher 
density of animals, which may have implications for differences in 
social structure and interactions within the population or with the 
pelagic population. Additionally, movement and photographic resighting 
data suggest Hawaiian insular false killer whales employ a unique 
foraging strategy compared to other false killer whales.
    Hawaiian insular false killer whales differ markedly from other 
populations of the species in their genetic characteristics. Hawaiian 
insular false killer whales exhibit strong phylogeographic patterns 
that are consistent with local evolution of mitochondrial haplotypes. 
Eighty of 81 individuals had one of two closely related haplotypes 
found nowhere else. These haplotypes are a sequence of a non-coding 
portion of the mtDNA and as such do not provide direct evidence for 
selection. The BRT found that the magnitude of mtDNA differentiation is 
large enough to infer that time has been sufficient and gene flow has 
been low enough to allow adaptation to the local Hawaiian habitat. The 
BRT noted that geneticists use one effective migrant per generation as 
a rule of thumb for the level of gene flow below which adaptation to 
local habitat is likely. Comparisons using mtDNA of the Hawaiian 
insular animals to those in all other geographic strata indicate less 
than one migrant per generation.
    Finally, culture, or knowledge passed through learning from one 
generation to the next, is likely to play an important role in the 
evolutionary potential of false killer whales. The insular population 
contributes to cultural diversity in the species, and this may provide 
the capacity for different amounts of cultural capabilities such as the 
ability of false killer whales to adapt to environmental change. 
Evidence in support of the significance of cultural diversity includes: 
Insular false killer whales may have unique knowledge of nearshore 
foraging areas and foraging tactics that are transmitted through 
learning. Learning is a common feature of other social odontocetes. 
False killer whales are highly social mammals with long interbirth 
intervals and reproductive senescence suggesting transfer of knowledge 
is important to successfully persist in this unique Hawaiian habitat. 
Learning to persist in this unique habitat, and knowing the intricacies 
of localized prey distribution and prey movements, may take many 
generations.
    Overall, the combination of genetic and behavioral discreteness 
coupled with ecological, genetic, and cultural significance led us to 
conclude that Hawaiian insular false killer whales are a DPS. There was 
some uncertainty in the genetic discontinuity factor of the 
discreteness conclusion based primarily on the lack of information on 
the adjacent population of pelagic false killer whales off the coast of 
Hawaii, and due to gaps in genetic sampling to the west of Hawaii. 
However, the BRT did not find this lack of information sufficient to 
alter the significance finding for Hawaiian insular false killer 
whales. We agree with the BRT's conclusion that the Hawaiian insular 
population of the false killer whale is a DPS.

Extinction Risk Assessment

Evaluating Threats

    The BRT qualitatively assessed potential individual threats to 
Hawaiian insular false killer whales and organized its assessment of 
threats according to the five factors listed under ESA section 4(a)(1). 
They evaluated the potential role that each factor may have played in 
the decline of Hawaiian insular false killer whales and the degree to 
which each factor is likely to limit population growth in the 
foreseeable future. Within the five factors, specific threats were 
individually ranked by considering the severity, geographic scope, the 
level of certainty that insular false killer whales are affected, and 
overall current and future (60 years) risk imposed by that threat. 
Consideration of future threats was limited to 60 years duration as 
this corresponds roughly to the life span of a false killer whale and 
represents a biologically relevant time horizon for projecting current 
conditions into the future.
    Section 4(a)(1) of the ESA and NMFS's implementing regulations (50 
CFR 424) state that the agency must determine whether a species is 
endangered or threatened because of any one or a combination of the 
five factors described under the ESA Statutory Provisions. The BRT was 
not asked to determine whether the DPS was endangered or threatened; it 
was only asked to assess the risk of extinction and the impact of 
factors affecting the DPS. The following discussion briefly summarizes 
the BRT's findings regarding threats to the Hawaiian insular false 
killer whale DPS. More details, including how the BRT voted, can be 
found in the status review report (Oleson et al., 2010). Overall, there 
were 29 threats identified to have either a historical, current, or 
future risk to Hawaiian insular false killer whales. Of these, 15 are 
believed to contribute most significantly to the current or future 
decline of Hawaiian insular false killer whales. The following is a 
summary of each of the 15 current and/or future potential threats that 
could result in either a high risk or medium risk of extinction, 
categorized according to the five section 4(a)(1) factors.
A: The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range
Reduced Total Prey Biomass and Reduced Prey Size
    The impacts of reduced total prey biomass and reduced prey size 
represent a medium risk for insular false killer whales. Although 
declines in prey biomass were more dramatic in the past when the 
insular false killer whale population may have been higher, the total 
prey abundance remains very low compared to the 1950s and 1960s as 
evidenced by catch-per-unit-effort (CPUE) data from Hawaii longline 
fisheries and biomass estimates from tuna stock assessments (Oleson et 
al., 2010). Long-term declines in prey size from the removal of large 
fish have been recorded from the earliest records to the future (Oleson 
et al., 2010).
Competition With Commercial Fisheries
    Competition with commercial fisheries is rated as a medium level of 
risk to current and future Hawaiian insular false killer whales. This 
risk exists because false killer whale prey includes many of the same 
species targeted by Hawaii's commercial fisheries, especially the 
fisheries for tuna, billfish, wahoo, and mahimahi.
    Until 1980, distant-water longliners from Japan caught between 
1,300 and 5,000 t of tuna and billfish annually within the U.S. EEZ 
around Hawaii (Yong and Wetherall, 1980). Since 1980 no foreign 
longline fishing has been legally conducted in this zone, but the U.S. 
Hawaii-based longline fisheries now harvest similar quantities of tuna 
and billfish in the EEZ. In terms of total hooks deployed by the U.S. 
domestic fisheries, the fisheries declined slightly in the 1960s and 
1970s, and then began to grow again in the 1980s. Total hooks in the 
U.S. EEZ around the main Hawaiian Islands in the period of 1965 and 
1977 were around 1.6 to 2.9 million hooks per year. As the domestic 
fisheries declined in the 1960s and 1970s, foreign fishing in the U.S. 
EEZ around the main Hawaiian Islands increased, and then ceased in 
1980. Domestic longlining was revitalized in the 1980s based on new 
markets for fresh tuna and the introduction of new shallow-set 
swordfish fishing methods.

[[Page 70177]]

Hooks deployed inside the U.S. EEZ around the main Hawaiian Islands in 
the 1990s were double that estimated for the 1970s, and doubled again 
in the 2000s. Participation in the Hawaii longline fisheries 
approximately doubled from 37 vessels in 1987 to 75 in 1989 and doubled 
again to 156 (vessels with permits) by the end of 1991. As the Hawaii-
based longline fisheries expanded during the late 1970s through the 
early 1990s, longline fishing effort increased in waters near the 
Hawaiian Islands and within the range of insular false killer whales. 
The expansion in these nearshore waters within the 40 km core habitat 
of the Hawaiian insular false killer whales was pronounced during an 
influx of new fisheries participants in the late 1980s (Ito, 1991) and 
this led to conflicts in the fishing areas previously dominated by 
troll and handline fishermen. The growing conflict between commercial 
longliners and near-shore troll and handliners was finally resolved in 
1992 with a prohibited area limiting nearshore longlining. Although the 
fraction of total Pacific longline tuna catches that are from the EEZ 
around the main Hawaiian Islands has declined from about half to about 
a quarter over the last two decades, the absolute quantity caught in 
the EEZ continued to increase through 2005, declining moderately 
thereafter (WPRFMC, 2010).
    The present-day Hawaiian insular false killer whale population 
requires an estimated 1.3 to 1.8 million kg of prey per year (Oleson et 
al., 2010). Competition with longline fisheries for potential prey 
within the insular false killer whale habitat seems to have represented 
a higher risk prior to the early 1990s when the longline fisheries were 
harvesting many millions of pounds of fish per year, and where reported 
catch locations were almost all in what is now the longline prohibited 
area. In the core nearshore habitat (<40 km from shore), the troll and 
handline fisheries now harvest as much as is estimated to be consumed 
annually by the Hawaiian insular false killer whale population.
Competition With Recreational Fisheries
    The potential limiting factor of reduced food due to catch removals 
by recreational fisheries was rated lower than for troll, handline, 
shortline, and kaka line fisheries in the status review report (Oleson 
et al., 2010). The BRT did not consider the estimates of recreational 
fishing for pelagic species ranging from 15-25 million lbs (7-11 
million kg) per year for 2003-2008 provided by the Marine Recreational 
Fisheries Survey (WPRFMC, 2010). Although the methods used to 
extrapolate statewide totals from the survey are being overhauled 
following a critical review, and although it is difficult to know what 
proportion of surveyed fishers' catch may be marketed surreptitiously, 
the extrapolated Hawaii recreational fisheries catch totals are many 
times higher than the reported commercial catch totals for the troll, 
handline, shortline, and kaka line fisheries considered by the BRT 
(Oleson et al., 2010). Reported commercial catches may be under-
reported, and some may be included in the recreational estimates, but 
if the nominal recreational estimates from the survey are even somewhat 
representative, then the recreational sector would represent at least 
as much competition for fish as the reported commercial troll handline, 
shortline, and kaka line fisheries. Thus, we believe competition with 
recreational fisheries should be rated as a medium level of current and 
future risk to Hawaiian insular false killer whales.
Natural or Anthropogenic Contaminants
    The threat of the accumulation of natural or anthropogenic 
contaminants, such as exposure to persistent organic pollutants (POPs), 
heavy metals (e.g., mercury, cadmium, lead), chemicals of emerging 
concern (industrial chemicals, current-use pesticides, pharmaceuticals, 
and personal care products), plastics, and oil, is rated as a medium 
level of current and future risk to Hawaiian insular false killer 
whales.
    Many toxic chemical compounds and heavy metals degrade slowly in 
the environment and thus tend to biomagnify in marine ecosystems, 
especially in lipid-rich tissues of top-level predators (McFarland and 
Clarke, 1989). In marine mammals, exposure to high levels of POPs has 
been associated with immunosuppression (Ross et al., 1995; Beckmen et 
al., 2003), reproductive dysfunction (Helle et al., 1976; Subramanian 
et al., 1987), and morphological changes (Zakharov and Yablokov, 1990; 
Sonne et al., 2004). Heavy metals have also been shown to accumulate in 
marine mammals and, in some cases, may cause deleterious biological 
effects, including alterations in steroid synthesis and liver damage 
(O'Hara and O'Shea, 2001). Many of these chemicals have been banned in 
the U.S. from production and use due to their toxic effects on wildlife 
and laboratory animals. As a result, the levels of these compounds in 
marine environmental samples in the U.S. have declined since the bans, 
including fish from Hawaii (Brasher and Wolff, 2004). However, some of 
these chemicals continue to be used in other regions of the world and 
can be transported to other areas via atmospheric transport or ocean 
currents (Fiedler, 2008; van den Berg, 2009). Even though these 
contaminants have been banned in the U.S. for more than 25 years, they 
continue to be measured in marine animals from Hawaii (Hunter, 1995; 
Kimbrough et al., 2008; Ylitalo et al., 2009).
    Independently the threat of bioaccumulation of chemicals is a cause 
for concern, but when coupled with the threat