Endangered and Threatened Species; Proposed Listing of Nine Distinct Population Segments of Loggerhead Sea Turtles as Endangered or Threatened, 12598-12656 [2010-5370]

Agencies

• DEPARTMENT OF COMMERCE
• National Oceanic and Atmospheric Administration
• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 75, Number 50 (Tuesday, March 16, 2010)]
[Proposed Rules]
[Pages 12598-12656]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-5370]



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Part II





Department of the Interior





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Fish and Wildlife Service



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Department of Commerce





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National Oceanic and Atmospheric Administration



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50 CFR Parts 17, 223, and 224



Endangered and Threatened Species; Proposed Listing of Nine Distinct 
Population Segments of Loggerhead Sea Turtles as Endangered or 
Threatened; Proposed Rule

Federal Register / Vol. 75 , No. 50 / Tuesday, March 16, 2010 / 
Proposed Rules

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Parts 223 and 224

[Docket No. 100104003-0004-01]
RIN 0648-AY49


Endangered and Threatened Species; Proposed Listing of Nine 
Distinct Population Segments of Loggerhead Sea Turtles as Endangered or 
Threatened

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce; United States Fish and 
Wildlife Service (USFWS), Interior.

ACTION: Proposed rules; 12-month petition findings; request for 
comments.

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SUMMARY: We (NMFS and USFWS; also collectively referred to as the 
Services) have determined that the loggerhead sea turtle (Caretta 
caretta) is composed of nine distinct population segments (DPSs) that 
qualify as ``species'' for listing as endangered or threatened under 
the Endangered Species Act (ESA), and we propose to list two as 
threatened and seven as endangered. This also constitutes the 12-month 
findings on a petition to reclassify loggerhead turtles in the North 
Pacific Ocean as a DPS with endangered status and designate critical 
habitat, and a petition to reclassify loggerhead turtles in the 
Northwest Atlantic as a DPS with endangered status and designate 
critical habitat. We will propose to designate critical habitat, if 
found to be prudent and determinable, for the two loggerhead sea turtle 
DPSs occurring within the United States in a subsequent Federal 
Register notice.

DATES: Comments on this proposal must be received by June 14, 2010. 
Public hearing requests must be received by June 1, 2010.

ADDRESSES: You may submit comments, identified by the RIN 0648-AY49, by 
any of the following methods:
     Electronic Submissions: Submit all electronic public 
comments via the Federal eRulemaking Portal.
     Mail: NMFS National Sea Turtle Coordinator, Attn: 
Loggerhead Proposed Listing Rule, Office of Protected Resources, 
National Marine Fisheries Service, 1315 East-West Highway, Room 13657, 
Silver Spring, MD 20910 or USFWS National Sea Turtle Coordinator, U.S. 
Fish and Wildlife Service, 7915 Baymeadows Way, Suite 200, 
Jacksonville, FL 32256.
     Fax: To the attention of NMFS National Sea Turtle 
Coordinator at 301-713-0376 or USFWS National Sea Turtle Coordinator at 
904-731-3045.
    Instructions: All comments received are a part of the public record 
and will generally be posted to https://www.regulations.gov without 
change. 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.
    NMFS and USFWS 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 proposed rule is 
available electronically at https://www.nmfs.noaa.gov/pr.

FOR FURTHER INFORMATION CONTACT: Barbara Schroeder, NMFS (ph. 301-713-
1401, fax 301-713-0376, e-mail barbara.schroeder@noaa.gov), Sandy 
MacPherson, USFWS (ph. 904-731-3336, e-mail sandy_macpherson@fws.gov), 
Marta Nammack, NMFS (ph. 301-713-1401, fax 301-713-0376, e-mail marta_nammack@noaa.gov), or Emily Bizwell, USFWS (ph. 404-679-7149, fax 404-
679-7081, e-mail emily_bizwell@fws.gov). Persons who use a 
Telecommunications device for the deaf (TDD) may call the Federal 
Information Relay Service (FIRS) at 1-800-877-8339, 24 hours a day, 7 
days a week.

SUPPLEMENTARY INFORMATION: 

Public Comments Solicited

    We solicit public comment on this proposed listing determination. 
We intend that any final action resulting from this proposal will be as 
accurate and as effective as possible and informed by the best 
available scientific and commercial information. Therefore, we request 
comments or information from the public, other concerned governmental 
agencies, the scientific community, industry, or any other interested 
party concerning this proposed rule. We are seeking information and 
comments on whether the nine proposed loggerhead sea turtle DPSs 
qualify as DPSs and, if so, whether they should be classified as 
threatened or endangered as described in the ``Listing Determinations 
Under the ESA'' section provided below. Specifically, we are soliciting 
information in the following areas relative to loggerhead turtles 
within the nine proposed DPSs: (1) Historical and current population 
status and trends, (2) historical and current distribution, (3) 
migratory movements and behavior, (4) genetic population structure, (5) 
current or planned activities that may adversely impact loggerhead 
turtles, and (6) ongoing efforts to protect loggerhead turtles. We are 
also soliciting information and comment on the status and effectiveness 
of conservation efforts and the approach that should be used to weigh 
the risk of extinction of each DPS. Comments and new information will 
be considered in making final determinations whether listing of each 
DPS is warranted and if so whether it is threatened or endangered. We 
request that all data, information, and comments be accompanied by 
supporting documentation such as maps, bibliographic references, or 
reprints of pertinent publications.

Background

    We issued a final rule listing the loggerhead sea turtle as 
threatened throughout its worldwide range on July 28, 1978 (43 FR 
32800). On July 12, 2007, we received a petition to list the ``North 
Pacific populations of loggerhead sea turtle'' as an endangered species 
under the ESA. NMFS published a notice in the Federal Register on 
November 16, 2007 (72 FR 64585), concluding that the petitioners 
(Center for Biological Diversity and Turtle Island Restoration Network) 
presented substantial scientific information indicating that the 
petitioned action may be warranted. Also, on November 15, 2007, we 
received a petition to list the ``Western North Atlantic populations of 
loggerhead sea turtle'' as an endangered species under the ESA. NMFS 
published a notice in the Federal Register on March 5, 2008 (73 FR 
11849), concluding that the petitioners (Center for Biological 
Diversity and Oceana) presented substantial scientific information 
indicating that the petitioned action may be warranted.
    On March 12, 2009, the petitioners (Center for Biological 
Diversity, Turtle Island Restoration Network, and Oceana) sent a 60-day 
notice of intent to sue to the Services for failure to make 12-month 
findings on the petitions. The statutory deadlines for the 12-month 
findings were July 16, 2008, for the North Pacific petition and 
November 16, 2008, for the Northwest Atlantic petition. On May 28, 
2009, the petitioners filed a Complaint for

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Declaratory and Injunctive Relief to compel the Services to complete 
the 12-month findings. On October 8, 2009, the petitioners and the 
Services reached a settlement in which the Services agreed to submit to 
the Federal Register a 12-month finding on the two petitions on or 
before February 19, 2010. On February 16, 2010, the United States 
District Court for the Northern District of California modified the 
February 19, 2010 deadline to March 8, 2010.
    In early 2008, NMFS assembled a Loggerhead Biological Review Team 
(BRT) to complete a status review of the loggerhead sea turtle. The BRT 
was composed of biologists from NMFS, USFWS, the Florida Fish and 
Wildlife Conservation Commission, and the North Carolina Wildlife 
Resources Commission. The BRT was charged with reviewing and evaluating 
all relevant scientific information relating to loggerhead population 
structure globally to determine whether DPSs exist and, if so, to 
assess the status of each DPS. The findings of the BRT, which are 
detailed in the ``Loggerhead Sea Turtle (Caretta caretta) 2009 Status 
Review under the U.S. Endangered Species Act'' (Conant et al., 2009; 
hereinafter referred to as the Status Review), addressed DPS 
delineations, extinction risks to the species, and threats to the 
species. The Status Review underwent independent peer review by nine 
scientists with expertise in loggerhead sea turtle biology, genetics, 
and modeling. The Status Review is available electronically at https://www.nmfs.noaa.gov/pr/species/statusreviews.htm.
    This Federal Register document announces 12-month findings on the 
petitions to list the North Pacific populations and the Northwest 
Atlantic populations of the loggerhead sea turtle as DPSs with 
endangered status and includes a proposed rule to designate nine 
loggerhead DPSs worldwide.

Policies for Delineating Species Under the ESA

    Section 3 of the ESA defines ``species'' as including ``any 
subspecies of fish or wildlife or plants, and any distinct population 
segment of any species of vertebrate fish or wildlife which interbreeds 
when mature.'' The term ``distinct population segment'' is not 
recognized in the scientific literature. Therefore, the Services 
adopted a joint policy for recognizing DPSs under the ESA (DPS Policy; 
61 FR 4722) on February 7, 1996. Congress has instructed the Secretary 
of the Interior or of Commerce to exercise this authority with regard 
to DPSs ``* * * sparingly and only when the biological evidence 
indicates such action is warranted.'' The DPS Policy requires the 
consideration of two elements when evaluating whether a vertebrate 
population segment qualifies as a DPS under the ESA: (1) The 
discreteness of the population segment in relation to the remainder of 
the species or subspecies to which it belongs; and (2) the significance 
of the population segment to the species or subspecies 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 (an 
organism or group of organisms) as a consequence of physical, 
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 (i.e., inadequate 
regulatory mechanisms).
    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. This consideration may 
include, but is not limited to: (1) Persistence of the discrete 
population segment in an ecological setting unusual or unique for the 
taxon; (2) evidence that 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; or (4) evidence that 
the discrete population segment differs markedly from other population 
segments of the species in its genetic characteristics.

Listing Determinations Under the ESA

    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 endangered in the 
foreseeable future throughout all or a significant portion of its range 
(sections 3(6) and 3(20), respectively). The statute requires us to 
determine whether any species is endangered or threatened because of 
any of the following five factors: (1) The present or threatened 
destruction, modification, or curtailment of its habitat or range; (2) 
overutilization 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 (section 4(a)(1)(A-E)). We are to 
make this determination based solely on the best available scientific 
and commercial data available 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.

Biology and Life History of Loggerhead Turtles

    A thorough account of loggerhead biology and life history may be 
found in the Status Review, which is incorporated here by reference. 
The following is a succinct summary of that information.
    The loggerhead occurs throughout the temperate and tropical regions 
of the Atlantic, Pacific, and Indian Oceans (Dodd, 1988). However, the 
majority of loggerhead nesting is at the western rims of the Atlantic 
and Indian Oceans. The most recent reviews show that only two 
loggerhead nesting aggregations have greater than 10,000 females 
nesting per year: Peninsular Florida, United States, and Masirah 
Island, Oman (Baldwin et al., 2003; Ehrhart et al., 2003; Kamezaki et 
al., 2003; Limpus and Limpus, 2003; Margaritoulis et al., 2003). 
Nesting aggregations with 1,000 to 9,999 females nesting annually are 
Georgia through North Carolina (United States), Quintana Roo and 
Yucatan (Mexico), Brazil, Cape Verde Islands (Cape Verde), Western 
Australia (Australia), and Japan. Smaller nesting aggregations with 100 
to 999 nesting females annually occur in the Northern Gulf of Mexico 
(United States), Dry Tortugas (United States), Cay Sal Bank (The 
Bahamas), Tongaland (South Africa), Mozambique, Arabian Sea Coast 
(Oman), Halaniyat Islands (Oman), Cyprus, Peloponnesus (Greece), 
Zakynthos (Greece), Crete (Greece), Turkey, and Queensland (Australia). 
In contrast to determining population size on nesting beaches, 
determining population size in the marine environment has been very 
localized. A summary of information on distribution and habitat by 
ocean basin follows.

Pacific Ocean

    Loggerheads can be found throughout tropical to temperate waters in 
the Pacific; however, their breeding grounds include a restricted 
number of sites in the North Pacific and South Pacific. Within the 
North Pacific, loggerhead nesting has been documented only in Japan 
(Kamezaki et al., 2003), although

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low level nesting may occur outside of Japan in areas surrounding the 
South China Sea (Chan et al., 2007). In the South Pacific, nesting 
beaches are restricted to eastern Australia and New Caledonia and, to a 
much lesser extent, Vanuatu and Tokelau (Limpus and Limpus, 2003).
    Based on tag-recapture studies, the East China Sea has been 
identified as the major habitat for post-nesting adult females (Iwamoto 
et al., 1985; Kamezaki et al., 1997; Balazs, 2006), while satellite 
tracking of juvenile loggerheads indicates the Kuroshio Extension 
Bifurcation Region to be an important pelagic foraging area for 
juvenile loggerheads (Polovina et al., 2006). Other important juvenile 
turtle foraging areas have been identified off the coast of Baja 
California Sur, Mexico (Pitman, 1990; Peckham and Nichols, 2006).
    Nesting females tagged on the coast of eastern Australia have been 
recorded foraging in New Caledonia; Queensland, New South Wales, and 
Northern Territory, Australia; Solomon Islands; Papua New Guinea; and 
Indonesia (Limpus and Limpus, 2003). Foraging Pacific loggerheads 
originating from nesting beaches in Australia are known to migrate to 
Chile and Peru (Alfaro-Shigueto et al., 2004, 2008a; Donoso and Dutton, 
2006; Boyle et al., 2009).

Indian Ocean

    In the North Indian Ocean, Oman hosts the vast majority of 
loggerhead nesting. The majority of the nesting in Oman occurs on 
Masirah Island, on the Al Halaniyat Islands, and on mainland beaches 
south of Masirah Island all the way to the Oman-Yemen border (IUCN--The 
World Conservation Union, 1989a, 1989b; Salm, 1991; Salm and Salm, 
1991). In addition, nesting probably occurs on the mainland of Yemen on 
the Arabian Sea coast, and nesting has been confirmed on Socotra, an 
island off the coast of Yemen (Pilcher and Saad, 2000). Limited 
information exists on the foraging habitats of North Indian Ocean 
loggerheads; however, foraging individuals have been reported off the 
southern coastline of Oman (Salm et al., 1993). Satellite telemetry 
studies of post-nesting migrations of loggerheads nesting on Masirah 
Island, Oman, have revealed extensive use of the waters off the Arabian 
Peninsula, with the majority of telemetered turtles traveling 
southwest, following the shoreline of southern Oman and Yemen, and 
circling well offshore in nearby oceanic waters (Environment Society of 
Oman and Ministry of Environment and Climate Change, Oman, unpublished 
data). A minority traveled north as far as the western Persian 
(Arabian) Gulf or followed the shoreline of southern Oman and Yemen as 
far west as the Gulf of Aden and the Bab-el-Mandab.
    The only verified nesting beaches for loggerheads on the Indian 
subcontinent are found in Sri Lanka. A small number of nesting females 
use the beaches of Sri Lanka every year (Deraniyagala, 1939; Kar and 
Bhaskar, 1982; Dodd, 1988); however, there are no records indicating 
that Sri Lanka has ever been a major nesting area for loggerheads 
(Kapurusinghe, 2006). No confirmed nesting occurs on the mainland of 
India (Tripathy, 2005; Kapurusinghe, 2006). The Gulf of Mannar provides 
foraging habitat for juvenile and post-nesting adult turtles (Tripathy, 
2005; Kapurusinghe, 2006).
    In the East Indian Ocean, western Australia hosts all known 
loggerhead nesting (Dodd, 1988). Nesting distributions in western 
Australia span from the Shark Bay World Heritage Area northward through 
the Ningaloo Marine Park coast to the North West Cape and to the nearby 
Muiron Islands (Baldwin et al., 2003). Nesting individuals from Dirk 
Hartog Island have been recorded foraging within Shark Bay and Exmouth 
Gulf, while other adults range much farther (Baldwin et al., 2003).
    In the Southwest Indian Ocean, loggerhead nesting occurs on the 
southeastern coast of Africa, from the Paradise Islands in Mozambique 
southward to St. Lucia in South Africa, and on the south and 
southwestern coasts of Madagascar (Baldwin et al., 2003). Foraging 
habitats are only known for post-nesting females from Tongaland, South 
Africa; tagging data show these loggerheads migrating eastward to 
Madagascar, northward to Mozambique, Tanzania, and Kenya, and southward 
to Cape Agulhas at the southernmost point of Africa (Baldwin et al., 
2003; Luschi et al., 2006).

Atlantic Ocean

    In the Northwest Atlantic, the majority of loggerhead nesting is 
concentrated along the coasts of the United States from southern 
Virginia through Alabama. Additional nesting beaches are found along 
the northern and western Gulf of Mexico, eastern Yucatan Peninsula, at 
Cay Sal Bank in the eastern Bahamas (Addison and Morford, 1996; 
Addison, 1997), on the southwestern coast of Cuba (F. Moncada-Gavilan, 
personal communication, cited in Ehrhart et al., 2003), and along the 
coasts of Central America, Colombia, Venezuela, and the eastern 
Caribbean Islands. In the Southwest Atlantic, loggerheads nest in 
significant numbers only in Brazil. In the eastern Atlantic, the 
largest nesting population of loggerheads is in the Cape Verde Islands 
(L.F. Lopez-Jurado, personal communication, cited in Ehrhart et al., 
2003), and some nesting occurs along the West African coast (Fretey, 
2001).
    As post-hatchlings, Northwest Atlantic loggerheads use the North 
Atlantic Gyre and enter Northeast Atlantic waters (Carr, 1987). They 
are also found in the Mediterranean Sea (Carreras et al., 2006; Eckert 
et al., 2008). In these areas, they overlap with animals originating 
from the Northeast Atlantic and the Mediterranean Sea (Laurent et al., 
1993, 1998; Bolten et al., 1998; LaCasella et al., 2005; Carreras et 
al., 2006; Monzon-Arguello et al., 2006; Revelles et al., 2007; Eckert 
et al., 2008). The oceanic juvenile stage in the North Atlantic has 
been primarily studied in the waters around the Azores and Madeira 
(Bolten, 2003). In Azorean waters, satellite telemetry data and flipper 
tag returns suggest a long period of residency (Bolten, 2003), whereas 
turtles appear to be moving through Madeiran waters (Dellinger and 
Freitas, 2000). Preliminary genetic analyses indicate that juvenile 
loggerheads found in Moroccan waters are of western Atlantic origin (M. 
Tiwari, NMFS, and A. Bolten, University of Florida, unpublished data). 
Other concentrations of oceanic juvenile turtles exist in the Atlantic 
(e.g., in the region of the Grand Banks off Newfoundland). Genetic 
information indicates the Grand Banks are foraging grounds for a 
mixture of loggerheads from all the North Atlantic rookeries (LaCasella 
et al., 2005; Bowen et al., 2005), and a large size range is 
represented (Watson et al., 2004, 2005).
    After departing the oceanic zone, neritic juvenile loggerheads in 
the Northwest Atlantic inhabit continental shelf waters from Cape Cod 
Bay, Massachusetts, south through Florida, The Bahamas, Cuba, and the 
Gulf of Mexico (neritic refers to the inshore marine environment from 
the surface to the sea floor where water depths do not exceed 200 
meters).
    Habitat preferences of Northwest Atlantic non-nesting adult 
loggerheads in the neritic zone differ from the juvenile stage in that 
relatively enclosed, shallow water estuarine habitats with limited 
ocean access are less frequently used. Areas such as Pamlico Sound and 
the Indian River Lagoon in the United States, regularly used by 
juvenile loggerheads, are only rarely frequented by adults. In 
comparison, estuarine areas with more open ocean access, such as 
Chesapeake Bay in the U.S. mid-Atlantic, are also regularly used by 
juvenile loggerheads, as well as by adults primarily during

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warmer seasons. Shallow water habitats with large expanses of open 
ocean access, such as Florida Bay, provide year-round resident foraging 
areas for significant numbers of male and female adult loggerheads. 
Offshore, adults primarily inhabit continental shelf waters, from New 
York south through Florida, The Bahamas, Cuba, and the Gulf of Mexico. 
The southern edge of the Grand Bahama Bank is important habitat for 
loggerheads nesting on the Cay Sal Bank in The Bahamas, but nesting 
females are also resident in the bights of Eleuthera, Long Island, and 
Ragged Islands as well as Florida Bay in the United States, and the 
north coast of Cuba (A. Bolten and K. Bjorndal, University of Florida, 
unpublished data). Moncada et al. (in press) reported the recapture in 
Cuban waters of five adult female loggerheads originally flipper tagged 
in Quintana Roo, Mexico, indicating that Cuban shelf waters likely also 
provide foraging habitat for adult females that nest in Mexico.
    In the Northeast Atlantic, satellite telemetry studies of post-
nesting females from Cape Verde identified two distinct dispersal 
patterns; larger individuals migrated to benthic foraging areas off the 
northwest Africa coast and smaller individuals foraged primarily 
oceanically off the northwest Africa coast (Hawkes et al., 2006). 
Monzon-Arguello et al. (2009) conducted a mixed stock analysis of 
juvenile loggerheads sampled from foraging areas in the Canary Islands, 
Madeira, Azores, and Andalusia and concluded that while juvenile 
loggerheads from the Cape Verde population were distributed among these 
four sites, a large proportion of Cape Verde juvenile turtles appear to 
inhabit as yet unidentified foraging areas.
    In the South Atlantic, relatively little is known about the at-sea 
behavior of loggerheads originating from nesting beaches in Brazil. 
Recaptures of tagged juvenile turtles and nesting females have shown 
movement of animals up and down the coast of South America (Almeida et 
al., 2000; Marcovaldi et al., 2000; Laporta and Lopez, 2003; Almeida et 
al., 2007). Juvenile loggerheads, presumably of Brazilian origin, have 
also been captured on the high seas of the South Atlantic (Kotas et 
al., 2004; Pinedo and Polacheck, 2004) and off the coast of Atlantic 
Africa (Bal et al., 2007; Petersen, 2005; Petersen et al., 2007) 
suggesting that loggerheads of the South Atlantic may undertake 
transoceanic developmental migrations (Bolten et al., 1998; Peckham et 
al., 2007).

Mediterranean Sea

    Loggerhead turtles are widely distributed in the Mediterranean Sea. 
However, nesting is almost entirely confined to the eastern 
Mediterranean basin, with the main nesting concentrations in Cyprus, 
Greece, and Turkey (Margaritoulis et al., 2003). Preliminary surveys in 
Libya suggested nesting activity comparable to Greece and Turkey, 
although a better quantification is needed (Laurent et al., 1999). 
Minimal to moderate nesting also occurs in other countries throughout 
the Mediterranean including Egypt, Israel, Italy (southern coasts and 
islands), Lebanon, Syria, and Tunisia (Margaritoulis et al., 2003). 
Recently, isolated nesting events have been recorded in the western 
Mediterranean basin, namely in Spain, Corsica (France), and in the 
Tyrrhenian Sea (Italy) (Tomas et al., 2002; Delaugerre and Cesarini, 
2004; Bentivegna et al., 2005).
    Important neritic habitats have been suggested for the large 
continental shelves of: (1) Tunisia-Libya, (2) northern Adriatic Sea, 
(3) Egypt, and (4) Spain (Margaritoulis, 1988; Argano et al., 1992; 
Laurent and Lescure, 1994; Lazar et al., 2000; Gomez de Segura et al., 
2006; Broderick et al., 2007; Casale et al., 2007b; Nada and Casale, 
2008). At least the first three constitute shallow benthic habitats for 
adults (including post-nesting females). Some other neritic foraging 
areas include Amvrakikos Bay in western Greece, Lakonikos Bay in 
southern Greece, and southern Turkey. Oceanic foraging areas for small 
juvenile loggerheads have been identified in the south Adriatic Sea 
(Casale et al., 2005b), Ionian Sea (Deflorio et al., 2005), Sicily 
Strait (Casale et al., 2007b), and western Mediterranean (Spain) (e.g., 
Cami[ntilde]as et al., 2006). In addition, tagged juvenile loggerheads 
have been recorded crossing the Mediterranean from the eastern to the 
western basin and vice versa, as well as in the Eastern Atlantic 
(Argano et al., 1992; Casale et al., 2007b).
    Reproductive migrations have been confirmed by flipper tagging and 
satellite telemetry. Female loggerheads, after nesting in Greece, 
migrate primarily to the Gulf of Gab[egrave]s and the northern Adriatic 
(Margaritoulis, 1988; Margaritoulis et al., 2003; Lazar et al., 2004; 
Zbinden et al., 2008). Loggerheads nesting in Cyprus migrate to Egypt 
and Libya, exhibiting fidelity in following the same migration route 
during subsequent nesting seasons (Broderick et al., 2007). In 
addition, directed movements of juvenile loggerheads have been 
confirmed through flipper tagging (Argano et al., 1992; Casale et al., 
2007b) and satellite tracking (Rees and Margaritoulis, 2009).

Overview of Information Used To Identify DPSs

    In the Status Review, the BRT considered a vast array of 
information to assess whether there are any loggerhead population 
segments that satisfy the DPS criteria of both discreteness and 
significance. First, the BRT examined whether there were any loggerhead 
population segments that were discrete. Data relevant to the 
discreteness question included physical, ecological, behavioral, and 
genetic data. Given the physical separation of ocean basins by 
continents, the BRT evaluated these data by ocean basin (Pacific Ocean, 
Indian Ocean, and Atlantic Ocean). This was not to preclude any larger 
or smaller DPS delineation, but to aid in data organization and 
assessment. The BRT then evaluated genetic information by ocean basin. 
The genetic data consisted of results from studies using maternally 
inherited mitochondrial DNA (mtDNA) and biparentally inherited nuclear 
DNA microsatellite markers. Next, tagging data (both flipper and PIT 
tags) and telemetry data were reviewed. Additional information, such as 
potential differences in morphology, was also evaluated. Finally, the 
BRT considered whether the available information on loggerhead 
population segments was bounded by any oceanographic features (e.g., 
current systems) or geographic features (e.g., land masses).
    In accordance with the DPS policy, the BRT also reviewed whether 
the population segments identified in the discreteness analysis were 
significant. If a population segment is considered discrete, its 
biological and ecological significance must then be considered. NMFS 
and USFWS must consider available scientific evidence of the discrete 
segment's importance to the taxon to which it belongs. Data relevant to 
the significance question include morphological, ecological, 
behavioral, and genetic data, as described above. The BRT considered 
the following factors, listed in the DPS policy, in determining whether 
the discrete population segments were significant: (a) Persistence of 
the discrete segment in an ecological setting unusual or unique for the 
taxon; (b) evidence that loss of the discrete segment would result in a 
significant gap in the range of the taxon; (c) evidence that the 
discrete segment represents the only surviving natural occurrence of a 
taxon that may be more abundant elsewhere as an introduced

[[Page 12602]]

population outside its historical range; and (d) evidence that the 
discrete segment differs markedly from other populations of the species 
in its genetic characteristics.
    A discrete population segment needs to satisfy only one of these 
criteria to be considered significant. The DPS policy also allows for 
consideration of other factors if they are appropriate to the biology 
or ecology of the species. As described below, the BRT evaluated the 
available information and considered items (a), (b) and (d), as noted 
above, to be most applicable to loggerheads.

Discreteness Determination

    As described in the Status Review, the loggerhead sea turtle is 
present in all tropical and temperate ocean basins, and has a life 
history that involves nesting on coastal beaches and foraging in 
neritic and oceanic habitats, as well as long-distance migrations 
between and within these areas. As with other globally distributed 
marine species, today's global loggerhead population has been shaped by 
a sequence of isolation events created by tectonic and oceanographic 
shifts over geologic time scales, the result of which is population 
substructuring in many areas (Bowen et al., 1994; Bowen, 2003). 
Globally, loggerhead turtles comprise a mosaic of populations, each 
with unique nesting sites and in many cases possessing disparate 
demographic features (e.g., mean body size, age at first reproduction) 
(Dodd, 1988). However, despite these differences, loggerheads from 
different nesting populations often mix in common foraging areas during 
certain life stages (Bolten and Witherington, 2003), thus creating 
unique challenges when attempting to delineate distinct population 
segments for management or listing purposes.
    Bowen et al. (1994) examined the mtDNA sequence diversity of 
loggerheads across their global distribution and found a separation of 
loggerheads in the Atlantic-Mediterranean basins from those in the 
Indo-Pacific basins since the Pleistocene period. The divergence 
between these two primary lineages corresponds to approximately three 
million years (2 percent per million years; Dutton et al., 1996; 
Encalada et al., 1996). Geography and climate appear to have shaped the 
evolution of these two matriarchal lineages with the onset of glacial 
cycles, the appearance of the Panama Isthmus creating a land barrier 
between the Atlantic and eastern Pacific, and upwelling of cold water 
off southern Africa creating an oceanographic barrier between the 
Atlantic and Indian Oceans (Bowen, 2003). Recent warm temperatures 
during interglacial periods allowed bi-directional invasion by the 
temperate-adapted loggerheads into the respective basins (Bowen et al., 
1994; J.S. Reece, Washington University, personal communication, 2008). 
Today, it appears that loggerheads within a basin are effectively 
isolated from populations in the other basin, but some dispersal from 
the Tongaland rookery in the Indian Ocean into feeding and 
developmental habitat in the South Atlantic is possible via the Agulhas 
Current (G.R. Hughes, unpublished data, cited in Bowen et al., 1994). 
In the Pacific, extensive mtDNA studies show that the northern 
loggerhead populations are isolated from the southern Pacific 
populations, and that juvenile loggerheads from these distinct genetic 
populations do not disperse across the equator (Hatase et al., 2002a; 
Dutton, 2007, unpublished data).
    Mitochondrial DNA data indicate that regional turtle rookeries 
within an ocean basin have been strongly isolated from one another over 
ecological timescales (Bowen et al., 1994; Bowen and Karl, 2007). These 
same data indicate strong female natal homing and suggest that each 
regional nesting population is an independent demographic unit (Bowen 
and Karl, 2007). It is difficult to determine the precise boundaries of 
these demographically independent populations in regions, such as the 
eastern U.S. coast, where rookeries are close to each other and range 
along large areas of a continental coastline. There appear to be 
varying levels of connectivity between proximate rookeries facilitated 
by imprecise natal homing and male mediated gene flow (Pearce, 2001; 
Bowen, 2003; Bowen et al., 2005). Regional genetic populations often 
are characterized by allelic frequency differences rather than fixed 
genetic differences.
    Through the evaluation of genetic data, tagging data, telemetry, 
and demography, the BRT determined that there are at least nine 
discrete population segments of loggerhead sea turtles globally. These 
discrete population segments are markedly separated from each other as 
a consequence of physical, ecological, behavioral, and oceanographic 
factors, and given the genetic evidence, the BRT concluded that each 
regional population identified is discrete from other populations of 
loggerheads. Information considered by the BRT in its delineation of 
discrete population segments is presented below by ocean basin.

Pacific Ocean

    In the North Pacific Ocean, the primary loggerhead nesting areas 
are found along the southern Japanese coastline and Ryukyu Archipelago 
(Kamezaki et al., 2003), although low level nesting may occur outside 
Japan in areas surrounding the South China Sea (Chan et al., 2007). 
Loggerhead turtles hatching on Japanese beaches undertake extensive 
developmental migrations using the Kuroshio and North Pacific Currents 
(Balazs, 2006; Kobayashi et al., 2008), and some turtles reach the 
vicinity of Baja California in the eastern Pacific (Uchida and Teruya, 
1988; Bowen et al., 1995; Peckham et al., 2007). After spending years 
foraging in the central and eastern Pacific, loggerheads return to 
their natal beaches for reproduction (Resendiz et al., 1998; Nichols et 
al., 2000) and remain in the western Pacific for the remainder of their 
life cycle (Iwamoto et al., 1985; Kamezaki et al., 1997; Sakamoto et 
al., 1997; Hatase et al., 2002c).
    Despite the long-distance developmental movements of loggerheads in 
the North Pacific, current scientific evidence, based on genetic 
analysis, flipper tag recoveries, and satellite telemetry, indicates 
that individuals originating from Japan remain in the North Pacific for 
their entire life cycle, never crossing the equator or mixing with 
individuals from the South Pacific (Hatase et al., 2002a; LeRoux and 
Dutton, 2006; Dutton, 2007, unpublished data). This apparent, almost 
complete separation of two adjacent populations most likely results 
from: (1) The presence of two distinct Northern and Southern Gyre 
(current flow) systems in the Pacific (Briggs, 1974), (2) near-passive 
movements of post-hatchlings in these gyres that initially move them 
farther away from areas of potential mixing among the two populations 
along the equator, and (3) the nest-site fidelity of adult turtles that 
prevents turtles from returning to non-natal nesting areas.
    Pacific loggerheads are further partitioned evolutionarily from 
other loggerheads throughout the world based on additional analyses of 
mtDNA. The haplotypes (a haplotype refers to the genetic signature, 
coded in mtDNA, of an individual) from both North and South Pacific 
loggerheads are distinguished by a minimum genetic distance (d) equal 
to 0.017 from other conspecifics, which indicates isolation of 
approximately one million years (Bowen, 2003).
    Within the Pacific, Bowen et al. (1995) used mtDNA to identify two 
genetically distinct nesting populations in the Pacific--a northern 
hemisphere population nesting in Japan and a southern hemisphere 
population nesting primarily in Australia. This study also

[[Page 12603]]

suggested that some loggerheads sampled as bycatch in the North Pacific 
might be from the Australian nesting population (Bowen et al., 1995). 
However, more extensive mtDNA rookery data from Japan (Hatase et al., 
2002a) taken together with preliminary results from microsatellite 
(nuclear) analysis confirms that loggerheads inhabiting the North 
Pacific actually originate from nesting beaches in Japan (P. Dutton, 
NMFS, unpublished data). LeRoux et al. (2008) reported additional 
genetic variation in North Pacific loggerheads based on analyses using 
new mtDNA primers designed to target longer mtDNA sequences, and 
suggested finer scale population structure in North Pacific loggerheads 
may be present.
    Although these studies indicate genetic distinctness between 
loggerheads nesting in Japan versus those nesting in Australia, Bowen 
et al. (1995) did identify individuals with the common Australian 
haplotype at foraging areas in the North Pacific, based on a few 
individuals sampled as bycatch in the North Pacific. More recently, 
Hatase et al. (2002a) detected this common haplotype at very low 
frequency at Japanese nesting beaches. However, the presence of the 
common Australian haplotype does not preclude the genetic 
distinctiveness of Japanese and Australian nesting populations, and is 
likely the result of rare gene flow events occurring over geologic time 
scales.
    The discrete status of loggerheads in the North Pacific is further 
supported by results from flipper tagging in the North Pacific. Flipper 
tagging of loggerheads has been widespread throughout this region, 
occurring on adults nesting in Japan and bycaught in the coastal pound 
net fishery (Y. Matsuzawa, Sea Turtle Association of Japan, personal 
communication, 2006), juvenile turtles reared and released in Japan 
(Uchida and Teruya, 1988; Hatase et al., 2002a), juvenile turtles 
foraging near Baja California, Mexico (Nichols, 2003; Seminoff et al., 
2004), and juvenile and adult loggerheads captured in and tagged from 
commercial fisheries platforms in the North Pacific high seas (NMFS, 
unpublished data). To date, there have been at least three transPacific 
tag recoveries showing east-west and west-east movements (Uchida and 
Teruya, 1988; Resendiz et al., 1998; W.J. Nichols, Ocean Conservancy, 
and H. Peckham, Pro Peninsula, unpublished data) and several recoveries 
of adults in the western Pacific (Iwamoto et al., 1985; Kamezaki et 
al., 1997). However, despite the more than 30,000 marked individuals, 
not a single tag recovery has been reported outside the North Pacific.
    A lack of movements by loggerheads south across the equator has 
also been supported by extensive satellite telemetry. As with flipper 
tagging, satellite telemetry has been conducted widely in the North 
Pacific, with satellite transmitters being placed on adult turtles 
departing nesting beaches (Sakamoto et al., 1997; Japan Fisheries 
Resource Conservation Association, 1999; Hatase et al., 2002b, 2002c), 
on adult and juvenile turtles bycaught in pound nets off the coast of 
Japan (Sea Turtle Association of Japan, unpublished data), on 
headstarted juvenile turtles released in Japan (Balazs, 2006), on 
juvenile and adult turtles bycaught in the eastern and central North 
Pacific (e.g., Kobayashi et al., 2008), and on juvenile turtles 
foraging in the eastern Pacific (Nichols, 2003; Peckham et al., 2007; 
J. Seminoff, NMFS, unpublished data). Of the nearly 200 loggerheads 
tracked using satellite telemetry in the North Pacific, none have moved 
south of the equator. These studies have demonstrated the strong 
association loggerheads show with oceanographic mesoscale features such 
as the Transition Zone Chlorophyll Front or the Kuroshio Current 
Bifurcation Region (Polovina et al., 2000, 2001, 2004, 2006; Etnoyer et 
al., 2006; Kobayashi et al., 2008). Kobayashi et al. (2008) 
demonstrated that loggerheads strongly track these zones even as they 
shift in location, suggesting that strong habitat specificity during 
the oceanic stage also contributes to the lack of mixing. Telemetry 
studies in foraging areas of the eastern Pacific, near Baja California, 
Mexico (Nichols, 2003; Peckham et al., 2007; H. Peckham, Pro Peninsula, 
unpublished data) and Peru (J. Mangel, Pro Delphinus, unpublished data) 
similarly showed a complete lack of long distance north or south 
movements.
    The North Pacific population of loggerheads appears to occupy an 
ecological setting distinct from other loggerheads, including those of 
the South Pacific population. This is the only known population of 
loggerheads to be found north of the equator in the Pacific Ocean, 
foraging in the eastern Pacific as far south as Baja California Sur, 
Mexico (Seminoff et al., 2004; Peckham et al., 2007) and in the western 
Pacific as far south as the Philippines (Limpus, 2009) and the mouth of 
Mekong River, Vietnam (Sadoyama et al., 1996). Pelagic juvenile turtles 
spend much of their time foraging in the central and eastern North 
Pacific Ocean. The Kuroshio Extension Current, lying west of the 
international date line, serves as the dominant physical and biological 
habitat in the North Pacific and is highly productive, likely due to 
unique features such as eddies and meanders that concentrate prey and 
support food webs. Juvenile loggerheads originating from nesting 
beaches in Japan exhibit high site fidelity to an area referred to as 
the Kuroshio Extension Bifurcation Region, an area with extensive 
meanders and mesoscale eddies (Polovina et al., 2006). Juvenile turtles 
also were found to correlate strongly with areas of surface chlorophyll 
a levels in an area known as the Transition Zone Chlorophyll Front, an 
area concentrating surface prey for loggerheads (Polovina et al., 2001; 
Parker et al., 2005; Kobayashi et al., 2008). Another area found 
ecologically unique to the North Pacific population of loggerheads, 
likely because of the high density of pelagic red crabs (Pleuronocodes 
planipes), is located off the Pacific coast of the Baja California 
Peninsula, Mexico, where researchers have documented a foraging area 
for juvenile turtles based on aerial surveys and satellite telemetry 
(Seminoff et al., 2006; Peckham et al., 2007). Tag returns show post-
nesting females migrating into the East China Sea off South Korea, 
China, and the Philippines, and the nearby coastal waters of Japan 
(Iwamoto et al., 1985; Kamezaki et al., 1997, 2003). Clearly, the North 
Pacific population of loggerheads is uniquely adapted to the ecological 
setting of the North Pacific Ocean and serves as an important part of 
the ecosystem it inhabits.
    In summary, loggerheads inhabiting the North Pacific Ocean are 
derived primarily, if not entirely, from Japanese beaches (although low 
level nesting may occur outside Japan in areas surrounding the South 
China Sea), with the possible exception of rare waifs over evolutionary 
time scales. Further, nesting colonies of Japanese loggerheads are 
found to be genetically distinct based on mtDNA analyses, and when 
compared to much larger and more genetically diverse loggerhead 
populations in the Atlantic and Mediterranean, Pacific loggerheads have 
likely experienced critical bottlenecks (in Hatase et al., 2002a), 
underscoring the importance of conservation and management to retain 
this genetically distinct population.
    In the South Pacific Ocean, loggerhead turtles nest primarily in 
Queensland, Australia, and, to a lesser extent, New Caledonia and 
Vanuatu (Limpus and Limpus, 2003; Limpus et al., 2006; Limpus, 2009). 
Loggerheads from these rookeries undertake an oceanic developmental 
migration,

[[Page 12604]]

traveling to habitats in the central and southeastern Pacific Ocean 
where they may reside for several years prior to returning to the 
western Pacific for reproduction. Loggerheads in this early life 
history stage differ markedly from those originating from western 
Australia beaches in that they undertake long west-to-east migrations, 
likely using specific areas of the pelagic environment of the South 
Pacific Ocean. An unknown portion of these loggerheads forage off Chile 
and Peru, and preliminary genetic information from foraging areas in 
the southeastern Pacific confirms that the haplotype frequencies among 
juvenile turtles in these areas closely match those found at nesting 
beaches in eastern Australia (Alfaro-Shigueto et al., 2004; Donoso and 
Dutton, 2006, 2007; Boyle et al., 2009). Large juvenile and adult 
loggerheads generally remain in the western South Pacific, inhabiting 
neritic and oceanic foraging sites during non-nesting periods (Limpus 
et al., 1994; Limpus, 2009).
    Loggerheads from Australia and New Caledonia apparently do not 
travel north of the equator. Flipper tag recoveries from nesting 
females have been found throughout the western Pacific, including sites 
north of Australia, the Torres Straight, and the Gulf of Carpentaria 
(Limpus, 2009). Of approximately 1,000 (adult and juvenile; male and 
female) loggerheads that have been tagged in eastern Australian feeding 
areas, only two have been recorded nesting outside of Australia; both 
traveled to New Caledonia (Limpus, 2009). Flipper tagging programs in 
Peru and Chile tagged approximately 500 loggerheads from 1999 to 2006, 
none of which have been reported from outside of the southeastern 
Pacific (Alfaro-Shigueto et al., 2008a; S. Kelez, Duke University 
Marine Laboratory, unpublished data; M. Donoso, ONG Pacifico Laud--
Chile, unpublished data). Limited satellite telemetry data from 12 
turtles in the area show a similar trend (J. Mangel, Pro Delphinus, 
unpublished data).
    The spatial separation between the North Pacific and South Pacific 
loggerhead populations has contributed to substantial differences in 
the genetic profiles of the nesting populations in these two regions. 
Whereas the dominant mtDNA haplotypes among loggerheads nesting in 
Japan are CCP2 and CCP3 (equivalent to B and C respectively in Bowen et 
al., 1995 and Hatase et al., 2002a; LeRoux et al., 2008; P. Dutton, 
NMFS, unpublished data), loggerheads nesting in eastern Australia have 
a third haplotype (CCP1, previously A) which is dominant (98 percent of 
nesting females) (Bowen et al., 1994; FitzSimmons et al., 1996; Boyle 
et al., 2009). Further, preliminary genetic analysis using 
microsatellite markers (nuclear DNA) indicates genetic distinctiveness 
between nesting populations in the North versus South Pacific (P. 
Dutton, NMFS, personal communication, 2008).
    The separateness between nesting populations in eastern Australia 
(in the South Pacific Ocean) and western Australia (in the East Indian 
Ocean) is less clear, although these too are considered to be 
genetically distinct from one another (Limpus, 2009). For example, 
mtDNA haplotype CCP1, which is the overwhelmingly dominant haplotype 
among eastern Australia nesting females (98 percent), is also found in 
western Australia, although at much lower frequency (33 percent) 
(FitzSimmons et al., 1996, 2003). The remaining haplotype for both 
regions was the CCP5 haplotype. Further, FitzSimmons (University of 
Canberra, unpublished data) found significant differences in nuclear 
DNA microsatellite loci from females nesting in these two regions. 
Estimates of gene flow between eastern and western Australian 
populations was an order of magnitude less than gene flow within 
regions. These preliminary results based on nuclear DNA indicate that 
male-mediated gene flow between eastern and western Australia may be 
insignificant, which, when considered in light of the substantial 
disparity in mtDNA haplotype frequencies between these two regions, 
provides further evidence of population separation.
    At present, there is no indication from genetic studies that the 
loggerhead turtles nesting in eastern Australia are distinct from those 
nesting in New Caledonia. Of 27 turtles sequenced from New Caledonia, 
93 percent carried the CCP1 haplotype and the remaining had the CCP5 
haplotype; similar to eastern Australia (Boyle et al., 2009).
    The South Pacific population of loggerheads occupies an ecological 
setting distinct from other loggerheads, including the North Pacific 
population; however, less is known about the ecosystem on which South 
Pacific oceanic juvenile and adult loggerheads depend. Sea surface 
temperature and chlorophyll frontal zones in the South Pacific have 
been shown to dramatically affect the movements of green turtles, 
Chelonia mydas (Seminoff et al., 2008) and leatherback turtles, 
Dermochelys coriacea (Shillinger et al., 2008), and it is likely that 
loggerhead distributions are also affected by these mesoscale 
oceanographic features.
    Loggerheads in the South Pacific are substantially impacted by 
periodic environmental perturbations such as the El Ni[ntilde]o 
Southern Oscillation (ENSO). This 3- to 6-year cycle within the coupled 
ocean-atmosphere system of the tropical Pacific brings increased 
surface water temperatures and lower primary productivity, both of 
which have profound biological consequences (Chavez et al., 1999). 
Loggerheads are presumably adversely impacted by the reduced food 
availability that often results from ENSO events, although data on this 
subject are lacking. Although ENSO may last for only short periods and 
thus not have a long-term effect on loggerheads in the region, recent 
studies by Chaloupka et al. (2008) suggested that long-term increases 
in sea surface temperature within the South Pacific may influence the 
ability of the Australian nesting population to recover from historic 
population declines.
    Loggerheads originating from nesting beaches in the western South 
Pacific are the only population of loggerheads to be found south of the 
equator in the Pacific Ocean. As post-hatchlings, they are generally 
swept south by the East Australian Current (Limpus et al., 1994), spend 
a large portion of time foraging in the oceanic South Pacific Ocean, 
and some migrate to the southeastern Pacific Ocean off the coasts of 
Peru and Chile as juvenile turtles (Alfaro-Shigueto et al., 2004; 
Donoso et al., 2000; Boyle et al., 2009). As large juveniles and 
adults, these loggerheads' foraging range encompasses the eastern 
Arafura Sea, Gulf of Carpentaria, Torres Strait, Gulf of Papua, Coral 
Sea, and western Tasman Sea to southern New South Wales including the 
Great Barrier Reef, Hervey Bay, and Moreton Bay. The outer extent of 
this range includes the coastal waters off eastern Indonesia 
northeastern Papua New Guinea, northeastern Solomon Islands, and New 
Caledonia (in Limpus, 2009).
    In summary, all loggerheads inhabiting the South Pacific Ocean are 
derived from beaches in eastern Australia and a lesser known number of 
beaches in southern New Caledonia, Vanuatu, and Tokelau (Limpus and 
Limpus, 2003; Limpus, 2009). Furthermore, nesting colonies of the South 
Pacific population of loggerheads are found to be genetically distinct 
from loggerheads in the North Pacific and Indian Ocean.
    Given the information presented above, the BRT concluded, and we 
concur, that two discrete population segments exist in the Pacific 
Ocean: (1) North Pacific Ocean and (2) South Pacific Ocean. These two 
population segments are markedly separated from

[[Page 12605]]

each other and from population segments within the Indian Ocean and 
Atlantic Ocean basins as a consequence of physical, ecological, 
behavioral, and oceanographic factors. Information supporting this 
conclusion includes genetic analysis, flipper tag recoveries, and 
satellite telemetry, which indicate that individuals originating from 
Japan remain in the North Pacific for their entire life cycle, never 
crossing the equator or mixing with individuals from the South Pacific 
(Hatase et al., 2002a; LeRoux and Dutton, 2006; Dutton, 2007, 
unpublished data). This apparent, almost complete separation most 
likely results from: (1) The presence of two distinct Northern and 
Southern Gyre (current flow) systems in the Pacific (Briggs, 1974), (2) 
near-passive movements of post-hatchlings in these gyres that initially 
move them farther away from areas of potential mixing along the 
equator, and (3) the nest-site fidelity of adult turtles that prevents 
turtles from returning to non-natal nesting areas. The separation of 
the Pacific Ocean population segments from population segments within 
the Indian Ocean and Atlantic Ocean basins is believed to be the result 
of land barriers and oceanographic barriers. Based on mtDNA analysis, 
Bowen et al. (1994) found a separation of loggerheads in the Atlantic-
Mediterranean basins from those in the Indo-Pacific basins since the 
Pleistocene period. Geography and climate appear to have shaped the 
evolution of these two matriarchal lineages with the onset of glacial 
cycles, the appearance of the Panama Isthmus creating a land barrier 
between the Atlantic and eastern Pacific, and upwelling of cold water 
off southern Africa creating an oceanographic barrier between the 
Atlantic and Indian Oceans (Bowen, 2003).

Indian Ocean

    Similar to loggerheads in the Pacific and Atlantic, loggerheads in 
the Indian Ocean nest on coastal beaches, forage in neritic and oceanic 
habitats, and undertake long-distance migrations between and within 
these areas. The distribution of loggerheads in the Indian Ocean is 
limited by the Asian landmass to the north (approximately 30[deg] N 
latitude); distributions east and west are not restricted by landmasses 
south of approximately 38[deg] S latitude.
    Historical accounts of loggerhead turtles in the Indian Ocean are 
found in Smith (1849), who described the species in South Africa, and 
Deraniyagala (1933, 1939) who described Indian Ocean loggerheads within 
the subspecies C. c. gigas. Hughes (1974) argued that there was little 
justification for this separation.
    In the North Indian Ocean, Oman hosts the vast majority of 
loggerhead nesting. The largest nesting assemblage is at Masirah 
Island, Oman, in the northern tropics at 21[deg] N latitude (Baldwin et 
al., 2003). Other key nesting assemblages occur on the Al Halaniyat 
Islands, Oman (17[deg] S latitude) and on Oman's Arabian Sea mainland 
beaches south of Masirah Island to the Oman-Yemen border (17-20[deg] S 
latitude) (IUCN--The World Conservation Union, 1989a, 1989b; Salm, 
1991; Salm and Salm, 1991; Baldwin et al., 2003). In addition, nesting 
probably occurs on the mainland of Yemen on the Arabian Sea coast, and 
nesting has been confirmed on Socotra, an island off the coast of Yemen 
(Pilcher and Saad, 2000).
    Outside of Oman, loggerhead nesting is rare in the North Indian 
Ocean. The only verified nesting beaches for loggerheads on the Indian 
subcontinent are found in Sri Lanka (Deraniyagala, 1939; Kar and 
Bhaskar, 1982; Dodd, 1988; Kapurusinghe, 2006). Reports of regular 
loggerhead nesting on the Indian mainland are likely misidentifications 
of olive ridleys (Lepidochelys olivacea) (Tripathy, 2005; Kapurusinghe, 
2006). Although loggerheads have been reported nesting in low numbers 
in Myanmar, these data may not be reliable because of misidentification 
of species (Thorbjarnarson et al., 2000).
    Limited information exists on foraging locations of North Indian 
Ocean loggerheads. Foraging individuals have been reported off the 
southern coastline of Oman (Salm et al., 1993) and in the Gulf of 
Mannar, between Sri Lanka and India (Tripathy, 2005; Kapurusinghe, 
2006). Satellite telemetry studies of post-nesting migrations of 
loggerheads nesting on Masirah Island, Oman, have revealed extensive 
use of the waters off the Arabian Peninsula, with the majority of 
telemetered turtles (15 of 20) traveling southwest, following the 
shoreline of southern Oman and Yemen, and circling well offshore in 
nearby oceanic waters (Environment Society of Oman and Ministry of 
Environment and Climate Change, Oman, unpublished data). A minority 
traveled north as far as the western Persian (Arabian) Gulf (3 of 20) 
or followed the shoreline of southern Oman and Yemen as far west as the 
Gulf of Aden and the Bab-el-Mandab (2 of 20). These preliminary data 
suggest that post-nesting migrations and adult female foraging areas 
may be centered within the region (Environment Society of Oman and 
Ministry of Environment and Climate Change, Oman, unpublished data). No 
tag returns or satellite tracks indicated that loggerheads nesting in 
Oman traveled south of the equator.
    In the East Indian Ocean, western Australia hosts all known 
loggerhead nesting (Dodd, 1988). Nesting distributions in western 
Australia span from the Shark Bay World Heritage Area northward through 
the Ningaloo Marine Park coast to the North West Cape and to the nearby 
Muiron Islands (Baldwin et al., 2003). Nesting individuals from Dirk 
Hartog Island have been recorded foraging within Shark Bay and Exmouth 
Gulf, while other adults range into the Gulf of Carpentaria (Baldwin et 
al., 2003). At the eastern extent of this apparent range, there is 
possible overlap with loggerheads that nest on Australia's Pacific 
coast (Limpus, 2009). However, despite extensive tagging at principal 
nesting beaches on Australia's Indian Ocean and Pacific coasts, no 
exchange of females between nesting beaches has been observed (Limpus, 
2009).
    Loggerhead nesting in the Southwest Indian Ocean includes the 
southeastern coast of Africa from the Paradise Islands in Mozambique 
southward to St. Lucia in South Africa, and on the south and 
southwestern coasts of Madagascar (Baldwin et al., 2003). Foraging 
habitats are only known for the Tongaland, South Africa, adult female 
loggerheads. Returns of flipper tags describe a range that extends 
eastward to Madagascar, northward to Mozambique, Tanzania, and Kenya, 
and southward to Cape Agulhas at the southernmost point of Africa 
(Baldwin et al., 2003). Four post-nesting loggerheads satellite tracked 
by Luschi et al. (2006) migrated northward, hugging the Mozambique 
coast and remained in shallow shelf waters off Mozambique for more than 
2 months. Only one post-nesting female from the Southwest Indian Ocean 
population (South Africa) has been documented migrating north of the 
equator (to southern Somalia) (Hughes and Bartholomew, 1996).
    The available genetic information relates to connectivity and broad 
evolutionary relationships between ocean basins. There is a lack of 
genetic information on population structure among rookeries within the 
Indian Ocean. Bowen et al. (1994) described mtDNA sequence diversity 
among eight loggerhead nesting assemblages and found one of two 
principal branches in the Indo-Pacific basins. Using additional 
published and unpublished data, Bowen (2003) estimated divergence 
between these two lineages to be approximately three million years. 
Bowen pointed out evidence for more recent colonizations (12,000-
250,000 years ago) between the Indian Ocean and the Atlantic-

[[Page 12606]]

Mediterranean. For example, the sole mtDNA haplotype (among eight 
samples) identified by Bowen et al. (1994) at Masirah Island, Oman, is 
known from the Atlantic and suggests some exchange between oceans some 
250,000 years ago. The other principal Indian Ocean haplotype reported 
by Bowen et al. (1994) was seen in all loggerheads sampled (n=15) from 
Natal, South Africa. Encalada et al. (1998) reported that this 
haplotype was common throughout the North Atlantic and Mediterranean, 
thus suggesting a similar exchange between the Atlantic and Indian 
Oceans as recently as 12,000 years ago (Bowen et al., 1994). Bowen 
(2003) speculated that Indian-Atlantic Ocean exchanges took place via 
the temperate waters south of South Africa and became rare as the ocean 
shifted to cold temperate conditions in this region.
    To estimate loggerhead gene flow in and out of the Indian Ocean, 
J.S. Reece (Washington University, personal communication, 2008) 
examined 100 samples from Masirah Island, 249 from Atlantic rookeries 
(from Encalada et al., 1998), and 311 from Pacific rookeries (from 
Hatase et al., 2002a and Bowen et al., 1995). Reece estimated that gene 
flow, expressed as number of effective migrants, or exchanges of 
breeding females between Indian Ocean rookeries and those from the 
Atlantic or Pacific occurred at the rate of less than 0.1 migrant per 
generation. Reece estimated gene flow based on coalescence of combined 
mtDNA and nuclear DNA data to be approximately 0.5 migrants per 
generation. These unpublished results, while somewhat theoretical, may 
indicate that there is restricted gene flow into and out of the Indian 
Ocean. The low level of gene flow most likely reflects the historical 
connectivity over geological timescales rather than any contemporary 
migration, and is consistent with Bowen's hypothesis that exchange 
occurred most recently over 12,000-3,000,000 years ago, and has been 
restricted over recent ecological timescales.
    The discrete status of three loggerhead populations in the Indian 
Ocean is primarily supported by observations of tag returns and 
satellite telemetry. The genetic information currently available based 
on mtDNA sequences does not allow for a comprehensive analysis of 
genetic population structure analysis for Indian Ocean rookeries, 
although Bowen et al. (1994) indicated the Oman and South African 
rookeries are genetically distinct, and once sequencing studies are 
completed for these rookeries, it is likely that they will also be 
genetically distinct from the rookeries in western Australia. Based on 
multiple lines of evidence, discrete status is supported for the North 
Indian Ocean, Southeast Indo-Pacific Ocean, and Southwest Indian Ocean 
loggerhead populations. Although there is not a sufficiently clear 
picture of gene flow between these regions, significant vicariant 
barriers likely exist between these three Indian Ocean populations that 
would prevent migration of individuals on a time scale relative to 
management and conservation efforts. These vicariant barriers are the 
oceanographic phenomena associated with Indian Ocean equatorial waters, 
and the large expanse between continents in the South Indian Ocean 
without suitable benthic foraging habitat.
    Given the information presented above, the BRT concluded, and w