[Federal Register Volume 80, Number 76 (Tuesday, April 21, 2015)]
[Proposed Rules]
[Pages 22304-22356]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-09010]
[[Page 22303]]
Vol. 80
Tuesday,
No. 76
April 21, 2015
Part III
Department of Commerce
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National Oceanic and Atmospheric Administration
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50 CFR Parts 223 and 224
Endangered and Threatened Species; Identification of 14 Distinct
Population Segments of the Humpback Whale (Megaptera novaeangliae) and
Proposed Revision of Species-Wide Listing; Proposed Rule
Federal Register / Vol. 80 , No. 76 / Tuesday, April 21, 2015 /
Proposed Rules
[[Page 22304]]
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DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric Administration
50 CFR Parts 223 and 224
[Docket No. 130708594-5298-02 ]
RIN 0648-XC751
Endangered and Threatened Species; Identification of 14 Distinct
Population Segments of the Humpback Whale (Megaptera novaeangliae) and
Proposed Revision of Species-Wide Listing
AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA), Commerce.
ACTION: Proposed rule; 12-month findings.
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SUMMARY: We, NMFS, have completed a comprehensive status review of the
humpback whale (Megaptera novaeangliae) under the Endangered Species
Act of 1973, as amended (ESA) (16 U.S.C. 1531 et seq.) and announce a
proposal to revise the listing status of the species. We propose to
divide the globally listed endangered species into 14 distinct
population segments (DPSs), remove the current species-level listing,
and in its place list 2 DPSs as endangered and 2 DPSs as threatened.
The remaining 10 DPSs are not proposed for listing based on their
current statuses. This proposal also constitutes a negative 12-month
finding on a petition to delineate and ``delist'' a DPS of humpback
whales spanning the entire North Pacific and a positive 12-month
finding on a petition to delineate and ``delist'' a DPS in the Central
North Pacific (Hawaii breeding population).
At this time, we do not propose to designate critical habitat for
the two listed DPSs that occur in U.S. waters (Western North Pacific,
Central America) because it is not currently determinable. In order to
complete the critical habitat designation process, we also solicit
information on essential physical and biological features of the
habitat of these two DPSs.
DATES: Comments must be submitted to NMFS by July 20, 2015. For
specific dates of the public hearings, see SUPPLEMENTARY INFORMATION.
Requests for additional public hearings must be made in writing and
received by June 5, 2015.
ADDRESSES: Four public hearings will be held, one each in Juneau, AK,
Honolulu, HI, Plymouth, MA, and Virginia Beach, VA. For specific
locations of these hearings, see SUPPLEMENTARY INFORMATION.
You may submit comments, identified by NOAA-NMFS-2015-0035, by any
of the following methods:
Electronic Submission: Submit all electronic public comments via
the Federal eRulemaking Portal.
1. Go to www.regulations.gov/#!docketDetail;D= NOAA-NMFS-2015-0035,
2. Click the ``Comment Now!'' icon, complete the required fields
3. Enter or attach your comments.
--Or--
Mail: Submit written comments to Marta Nammack, NMFS, 1315 East-
West Highway, Room 13536, Silver Spring, MD 20910.
Instructions: Comments sent by any other method, to any other
address or individual, or received after the end of the comment period,
may not be considered by NMFS. All comments received are a part of the
public record and will generally be posted for public viewing on
www.regulations.gov without change. All personal identifying
information (e.g., name, address, etc.), confidential business
information, or otherwise sensitive information submitted voluntarily
by the sender will be publicly accessible. NMFS will accept anonymous
comments (enter ``N/A'' in the required fields if you wish to remain
anonymous).
The proposed rule, Status Review report and other materials
relating to this proposal can be found on the NMFS Web site at: http://nmfs.noaa.gov/pr/.
FOR FURTHER INFORMATION CONTACT: Marta Nammack, NMFS, (301) 427-8469.
SUPPLEMENTARY INFORMATION: On August 12, 2009, we announced the
initiation of a status review of the humpback whale to determine
whether an endangered listing for the entire species was still
appropriate (74 FR 40568). We sought information from the public to
inform our review, hired two post-doctoral students to compile the best
available scientific and commercial information on the species (Fleming
and Jackson, 2011), including the past, present, and foreseeable future
threats to this species, and appointed a Biological Review Team (BRT)
to analyze that information, make conclusions on extinction risk, and
prepare a status review report (Bettridge et al., 2015).
On April 16, 2013, we received a petition from the Hawaii
Fishermen's Alliance for Conservation and Tradition, Inc., to classify
the North Pacific humpback whale population as a DPS and ``delist'' the
DPS under the Endangered Species Act (ESA). On February 26, 2014, the
State of Alaska submitted a petition to delineate the Central North
Pacific (Hawaii) stock of the humpback whale as a DPS and remove the
DPS from the List of Endangered and Threatened Species under the ESA.
After reviewing the petitions, the literature cited in the petitions,
and other literature and information available in our files, we found
that both petitioned actions may be warranted and issued positive 90-
day findings (78 FR 53391, August 29, 2013; 79 FR 36281, June 26,
2014). We extended the deadline for receiving information by 30 days to
help us respond to the petition to delist the Central North Pacific
population (79 FR 40054; July 11, 2014). We incorporated the
consideration of both petitioned actions into the status review.
Based on information presented in the status review report, an
assessment of the ESA section 4(a)(1) factors, and efforts being made
to protect the species, we have determined: (1) 14 populations of the
humpback whale meet the DPS policy criteria and are therefore
considered to be DPSs; (2) the Cape Verde Islands/Northwest Africa and
Arabian Sea DPSs are in danger of extinction throughout their ranges;
(3) the Western North Pacific and Central America DPSs are likely to
become endangered throughout all of their ranges in the foreseeable
future; and (4) the West Indies, Hawaii, Mexico, Brazil, Gabon/
Southwest Africa, Southeast Africa/Madagascar, West Australia, East
Australia, Oceania, and Southeastern Pacific DPSs are not in danger of
extinction throughout all or a significant portion of their ranges or
likely to become so in the foreseeable future. Accordingly, we issue a
proposed rule to revise the species-wide listing of the humpback whale
by replacing it with 2 endangered species listings (Cape Verde Islands/
Northwest Africa and Arabian Sea DPSs) and 2 threatened species
listings (Western North Pacific and Central America DPSs). We solicit
comments on these proposed actions. We also propose to extend the ESA
section 9 prohibitions to the 2 threatened DPSs.
Outline
ESA Statutory Provisions, Regulations, and Policy Considerations
Distinct Population Segment Policy
``Foreseeable Future''
``Significant Portion of its Range''
Background
Behavior
Feeding
Reproduction
Natural Mortality
Status Review Report
Humpback Whale Subspecies
[[Page 22305]]
Reproductive Seasonality
Behavior
Color patterns
Genetics
Subspecies Discussion and Conclusions
Distinct Population Segment Analysis, By Subspecies
North Atlantic
Overview
Discreteness
Significance
North Pacific
Overview
Discreteness
Significance
Southern Hemisphere
Overview:
Discreteness
Significance
Extinction Risk Assessment
Abundance and Trends for Each DPS
West Indies DPS
Cape Verde Islands/Northwest Africa DPS
Western North Pacific DPS
Hawaii DPS
Mexico DPS
Central America DPS
Brazil DPS
Gabon/Southwest Africa DPS
Southeast Africa/Madagascar DPS
West Australia DPS
East Australia DPS
Oceania DPS
Southeastern Pacific DPS
Arabian Sea DPS
Summary of Abundance and Trends
Summary of Section 4(a)(1) Factors Affecting the 14 Humpback Whale
DPSs
Section 4(a)(1) Factors Applicable to All DPSs
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes:
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
West Indies DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Cape Verde Islands/Northwest Africa DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Western North Pacific DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Hawaii DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Mexico DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Central America DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Brazil DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Gabon/Southwest Africa DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Southeast Africa/Madagascar DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
West Australia DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
East Australia DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Oceania DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Southeastern Pacific DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Arabian Sea DPS
A. The present or Threatened Destruction, Modification, or
Curtailment of its Habitat or Range
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
C. Disease or Predation
D. Inadequacy of Existing Regulatory Mechanisms
E. Other Natural or Manmade Factors Affecting its Continued
Existence
Ongoing Conservation Efforts
Rationale for Revising the Current Global Listing and Replacing It
with Listings of DPSs
Conclusions on the Status of Each DPS under the ESA
Endangered DPSs
Threatened DPSs
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DPSs Not Warranted for Listing under the ESA
Post-delisting Monitoring Plan
Description of Proposed Regulatory Changes
Prohibitions and Protective Measures
Identification of Those Activities That Would Constitute a Violation
of Section 9 of the ESA
Effects of this Rulemaking
Peer Review
Critical Habitat
Public Comments Solicited
Public Hearings
Classification
National Environmental Policy Act (NEPA)
Executive Order (E.O.) 12866, Regulatory Flexibility Act, and
Paperwork Reduction Act
E.O. 13132, Federalism
E.O. 13175, Consultation and Coordination with Indian Tribal
Governments
ESA Statutory Provisions, Regulations, and Policy Considerations
Pursuant to the ESA, any interested person may petition to list or
delist a species, subspecies, or DPS of a vertebrate species that
interbreeds when mature (5 U.S.C. 553(e), 16 U.S.C. 1533(b)(3)(A)).
ESA-implementing regulations issued by NMFS and the U.S. Fish and
Wildlife Service (FWS) also establish procedures for receiving and
considering petitions to revise the lists of endangered and threatened
species and for conducting periodic reviews of listed species (50 CFR
424.01).
Once we receive a petition to delist a species, the ESA requires
the Secretary of Commerce (Secretary) to make a finding on whether the
petition presents substantial scientific or commercial information
indicating that the petitioned action may be warranted (16 U.S.C.
1533(b)(3)(A)). In the context of a petition to delist a species, the
ESA-implementing regulations provide that ``substantial information''
is that amount of information that would lead a reasonable person to
believe that delisting may be warranted (50 CFR 424.14(b)(1)). In
determining whether substantial information exists, we take into
account several factors, in light of any information noted in the
petition or otherwise readily available in our files. To the maximum
extent practicable, this finding is to be made within 90 days of the
receipt of the petition (16 U.S.C. 1533(b)(3)(A)) and published
promptly in the Federal Register. Section 4(b)(3)(B) of the ESA
requires that, when a petition to revise the List of Endangered and
Threatened Wildlife and Plants is found to present substantial
scientific and commercial information, we make a finding that the
petitioned action is (a) not warranted, (b) warranted, or (c) warranted
but precluded from immediate proposal by other pending proposals of
higher priority. This finding (the ``12-month finding'') is to be made
within 1 year of the date the petition was received, and the finding is
to be published promptly in the Federal Register. The Secretary has
delegated the authority for these actions to the NOAA Assistant
Administrator for Fisheries.
Section 3 of the ESA defines an endangered species as ``any species
which is in danger of extinction throughout all or a significant
portion of its range'' and a threatened species as one ``which is
likely to become an endangered species within the foreseeable future
throughout all or a significant portion of its range.'' Thus, we
interpret an ``endangered species'' to be one that is presently in
danger of extinction. A ``threatened species,'' on the other hand, is
not presently in danger of extinction, but is likely to become so in
the foreseeable future (that is, at a later time). In other words, the
primary statutory difference between a threatened and endangered
species is the timing of when a species may be in danger of extinction,
either presently (endangered) or in the foreseeable future
(threatened). In determining whether to reclassify or delist a species,
subspecies, or DPS, the ESA and implementing regulations require that
we consider the following ESA section 4(a)(1) factors in relation to
the definitions of ``endangered species'' or ``threatened species'' (16
U.S.C. 1533(a)(1) and 1533(c)(2); 50 CFR 424.11(d)): The present or
threatened destruction, modification, or curtailment of its habitat or
range; overutilization of the species for commercial, recreational,
scientific, or educational purposes; disease or predation; the
inadequacy of existing regulatory mechanisms; and other natural or
manmade factors affecting a species' continued existence. These are the
same factors that we must consider when making an initial determination
whether to list a species, subspecies, or DPS as threatened or
endangered under the ESA.
Section 4(b)(1)(A) of the ESA requires us to make listing
determinations based solely on the best scientific and commercial data
available after conducting a review of the status of the species and
after taking into account efforts being made by any State or foreign
nation or political subdivision thereof to protect the species. In
evaluating the efficacy of protective efforts not yet implemented or
not yet proven to be effective, we rely on the Policy on Evaluation of
Conservation Efforts When Making Listing Decisions (``PECE''; 68 FR
15100; March 28, 2003) issued jointly by NMFS and the FWS (together,
the Services). The ESA regulations require that a species listed as
endangered or threatened be removed from the list if the best
scientific or commercial data available indicate that the species is no
longer endangered or threatened because it has recovered (50 CFR
424.11(d)).
Distinct Population Segment Policy
To be considered for listing under the ESA, a group of organisms
must constitute a ``species,'' which the ESA defines to include ``. . .
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'' (16 U.S.C. 1532 (16)). Thus, an ESA listing
(or delisting) determination can address a species, subspecies, or a
DPS of a vertebrate species.
On February 7, 1996, the Services adopted a policy describing what
constitutes a DPS of a taxonomic species (61 FR 4722). The joint DPS
policy identified two elements that must be considered when identifying
a DPS: (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 remainder of 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 as a consequence of physical, physiological, ecological, or
behavioral factors. Quantitative measures of genetic or morphological
discontinuity may provide evidence of this separation.
(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 considered discrete under one or more of
the above conditions, its biological and ecological significance is
then considered in light of Congressional guidance (see Senate Report
151, 96th Congress, 1st Session) that the authority to list DPSs be
used ``sparingly'' while encouraging the conservation of genetic
diversity. This consideration may include, but is not limited to, the
following:
(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;
[[Page 22307]]
(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 populations of the species in its genetic characteristics.
``Foreseeable Future''
To determine whether listing of a species is warranted, a status
review must conclude that the species is ``in danger of extinction or
likely to become so within the foreseeable future throughout all or a
significant portion of its range.'' The ESA uses the term ``foreseeable
future'' to refer to the time over which identified threats are likely
to impact the biological status of the species. The duration of the
``foreseeable future'' in any circumstance is inherently fact-specific
and depends on the particular kinds of threats, the life-history
characteristics, and the specific habitat requirements for the species
under consideration. The existence of a threat to a species and the
species' response to that threat are not, in general, equally
predictable or foreseeable. Hence, in some cases, the ability to
foresee a threat to a species is greater than the ability to foresee
the species' exact response, or the timeframe of such a response, to
that threat. For purposes of making these 12-month findings, the
relevant consideration is whether the species' population response
(i.e., abundance, productivity, spatial distribution, diversity) is
foreseeable, not merely whether the emergence of a threat is
foreseeable. The foreseeable future extends only as far as we are able
to reliably predict the species' population response to a particular
threat. We consider the extent to which we can foresee the species'
response to each threat.
``Significant Portion of its Range''
NMFS and FWS recently published a final policy to clarify the
interpretation of the phrase ``significant portion of the range'' in
the ESA definitions of ``threatened species'' and ``endangered
species'' (79 FR 37577; July 1, 2014) (Final Policy). The Final Policy
reads:
Consequences of a species being endangered or threatened
throughout a significant portion of its range: The phrase
``significant portion of its range'' in the Act's definitions of
``endangered species'' and ``threatened species'' provides an
independent basis for listing. Thus, there are two situations (or
factual bases) under which a species would qualify for listing: A
species may be endangered or threatened throughout all of its range
or a species may be endangered or threatened throughout only a
significant portion of its range.
If a species is found to be endangered or threatened throughout
only a significant portion of its range, the entire species is
listed as endangered or threatened, respectively, and the Act's
protections apply to all individuals of the species wherever found.
Significant: A portion of the range of a species is
``significant'' if the species is not currently endangered or
threatened throughout its range, but the portion's contribution to
the viability of the species is so important that, without the
members in that portion, the species would be in danger of
extinction, or likely to become so in the foreseeable future,
throughout all of its range.
Range: The range of a species is considered to be the general
geographical area within which that species can be found at the time
FWS or NMFS makes any particular status determination. This range
includes those areas used throughout all or part of the species'
life cycle, even if they are not used regularly (e.g., seasonal
habitats). Lost historical range is relevant to the analysis of the
status of the species, but it cannot constitute a significant
portion of a species' range.
Reconciling SPR with DPS authority: If the species is endangered
or threatened throughout a significant portion of its range, and the
population in that significant portion is a valid DPS, we will list
the DPS rather than the entire taxonomic species or subspecies.
The Final Policy explains that it is necessary to fully evaluate a
portion for potential listing under the ``significant portion of its
range'' authority only if substantial information indicates that the
members of the species in a particular area are likely both to meet the
test for biological significance and to be currently endangered or
threatened in that area. Making this preliminary determination triggers
a need for further review, but does not prejudge whether the portion
actually meets these standards such that the species should be listed:
To identify only those portions that warrant further
consideration, we will determine whether there is substantial
information indicating that (1) the portions may be significant and
(2) the species may be in danger of extinction in those portions or
likely to become so within the foreseeable future. We emphasize that
answering these questions in the affirmative is not a determination
that the species is endangered or threatened throughout a
significant portion of its range--rather, it is a step in
determining whether a more detailed analysis of the issue is
required.
79 FR 37586.
Thus, the preliminary determination that a portion may be both
significant and endangered or threatened merely requires NMFS to engage
in a more detailed analysis to determine whether the standards are
actually met. Id. at 37587. Unless both are met, listing is not
warranted. The Final Policy explains that, depending on the particular
facts of each situation, NMFS may find it is more efficient to address
the significance issue first, but in other cases it will make more
sense to examine the status of the species in the potentially
significant portions first. Whichever question is asked first, an
affirmative answer is required to proceed to the second question. Id.
(``[I]f we determine that a portion of the range is not
``significant,'' we will not need to determine whether the species is
endangered or threatened there; if we determine that the species is not
endangered or threatened in a portion of its range, we will not need to
determine if that portion was ``significant.''). Thus, if the answer to
the first question is negative--whether in regard to the significance
question or the status question--then the analysis concludes and
listing is not warranted.
Background
The humpback whale (Megaptera novaeangliae) was listed as
endangered in 1970 under the Endangered Species Conservation Act of
1969, the precursor to the ESA. When the ESA was enacted in 1973, the
humpback whale was transferred to the List of Endangered and Threatened
Wildlife and Plants, retaining endangered status, and, because of its
endangered ESA status, was considered ``depleted'' under the Marine
Mammal Protection Act (MMPA). NMFS issued a recovery plan for the
humpback whale in 1991, and its long-term numerical goal was to
increase humpback whale populations to at least 60 percent of the
number existing before commercial exploitation or of current
environmental carrying capacity. The recovery team recognized that
those levels could not then be determined, so in the meantime, the
interim goal of the recovery plan was to double the population size of
extant populations within the next 20 years (http://www.nmfs.noaa.gov/pr/pdfs/recovery/whale_humpback.pdf). In fact, the historical size of
humpback whale populations continues to be uncertain (Ruegg et al.,
2013, and references therein; Bettridge et al., 2015).
The taxonomy, life history, and ecology of the humpback whale are
thoroughly reviewed in Fleming and Jackson (2011) and summarized in the
BRT's status review report (Bettridge et al., 2015; available at http://www.nmfs.noaa.gov/pr/species/statusreviews.htm). The humpback whale is
a large baleen whale of the
[[Page 22308]]
family Balaenopteridae. It is found around the world in all oceans. The
humpback whale has long pectoral flippers, distinct ventral fluke
patterning, dark dorsal coloration, a highly varied acoustic call
(termed `song'), and a diverse repertoire of surface behaviors.
Its body coloration is primarily dark grey, but individuals have a
variable amount of white on their pectoral fins, flukes, and belly.
This variation is so distinctive that the pigmentation pattern on the
undersides of their flukes is used to identify individual whales.
Coloring of the ventral surface varies from white to marbled to fully
black. Dorsal surfaces of humpback whale pectoral flippers are
typically white in the North Atlantic and black in the North Pacific
(Perrin et al., 2002), and the flippers are about one-third of the
total body length. Similar to all baleen whales, body lengths differ
between the sexes, with adult females being approximately 1-1.5m longer
than males. The humpback whale reaches a maximum of 16-17 m, although
lengths of 14-15 m are more typical. Adult body weights in excess of 40
tons make them one of the largest mammals on earth (Ohsumi, 1966).
With one exception, humpback whales are highly migratory, spending
spring, summer, and fall feeding in temperate or high-latitude areas of
the North Atlantic, North Pacific, and Southern Ocean and migrating to
the tropics in winter to breed and calve. The Arabian Sea humpback
whale population does not migrate extensively, remaining in tropical
waters year-round (Baldwin, 2000; Minton et al., 2010b).
There are 14 known breeding grounds for humpback whales, and there
may be other breeding grounds of unknown location. Whales using the
unknown breeding grounds may be associated to some degree with whales
from the known breeding grounds.
Whales from all known breeding grounds except the Arabian Sea
migrate to summer feeding areas. Humpback whales have high site
fidelity to both the winter breeding grounds and summer feeding
grounds. Whales from a single breeding ground may migrate to different
feeding grounds. In addition, feeding grounds may host whales from
different breeding grounds. Because humpback whales can be individually
identified through unique fluke patterns, researchers are able to match
photos of whales on breeding grounds and feeding grounds, thereby
tracing their migrations.
Although the patterns of migration and distribution are clear for
many breeding groups, researchers have identified whales on some
feeding grounds that have never been sighted in any of the known
breeding grounds. Depending on the strength of the evidence, scientists
may infer that an additional breeding population exists but that its
breeding grounds are unknown. We explore this subject further in the
``Distinct Population Segment Analysis, By Subspecies'' section below.
Behavior
Humpback whales travel great distances during migration, the
farthest migration of any mammal. The longest recorded migration
between a breeding area and a feeding area was 5,160 miles (8,300 km).
This trek from Costa Rica to Antarctica was completed by seven
individuals, including a calf (Rasmussen et al., 2007). One of the more
closely studied routes has shown whales making the 3,000-mile (4,830
km) trip between Alaska and Hawaii in as little as 36 days (Allen and
Angliss, 2010).
During summer and fall, humpback whales spend much of their time
feeding and building fat stores for winter. In their low-latitude
wintering grounds, humpback whales congregate and are believed to
engage in mating and other social activities. Humpback whales are
generally polygynous, with males exhibiting competitive behavior on
wintering grounds (Tyack, 1981; Baker and Herman, 1984; Clapham, 1996).
A complex behavioral repertoire exhibited in these areas can include
aggressive and antagonistic behavior, such as chasing, vocal and bubble
displays, horizontal tail thrashing, and rear body thrashing. Males
within these groups also make physical contact, striking or surfacing
on top of one another.
Also on wintering grounds, males sing complex songs that can last
up to 20 minutes and may be heard up to 20 miles (30 km) away (Clapham
and Mattila, 1990; Cato, 1991). A male may sing for hours, repeating
the song numerous times. All males in a population sing the same song,
but that song continually evolves over time (Darling and Sousa-Lima,
2005). Humpback whale singing has been studied for decades, but its
function remains in dispute.
Humpback whales are a favorite of whale watchers, as the species
frequently performs aerial displays, including breaching, lobtailing,
and flipper slapping, the purposes of which are not well understood.
Diving behavior varies by season, with average lengths of dives ranging
from <5 minutes in summer to 10-15 minutes (and sometimes more than 30
minutes) in winter months (Clapham and Mead, 1999). Typically, humpback
whale groups are small (e.g., <10 individuals, but can vary depending
on social context and season), and associations between individuals do
not last long, with the exception of the mother/calf pairs (Clapham and
Mead, 1999).
Feeding
Humpback whales have a diverse diet that varies slightly across
feeding areas. The species is known to feed on both small schooling
fish and on euphausiids (krill). Known prey organisms include species
representing Clupea (herring), Scomber (mackerel), Ammodytes (sand
lance), Sardinops (sardine), Engraulis (anchovy), Mallotus (capelin),
and krills such as Euphausia, Thysanoessa, and Meganyctiphanes (Baker,
1985; Geraci et al., 1989; Clapham et al., 1997). Humpback whales also
exhibit flexible feeding strategies, sometimes foraging alone and
sometimes cooperatively (Clapham, 1993). During the winter, humpback
whales subsist on stored fat and likely feed little or not at all.
In the Northern Hemisphere, feeding behavior is varied and
frequently features novel capture methods involving the creation of
bubble structures to trap and corral fish; bubble nets, clouds, and
curtains can be observed when humpback whales are feeding on schooling
fish (Hain et al., 1982). Lobtailing and repeated underwater `looping'
movements (referred to as kick feeding) have also been observed during
surface feeding events, and it may be that certain feeding behaviors
are spread through the population by cultural transmission (Weinrich et
al., 1992; Friedlaender et al., 2006). On Stellwagen Bank, in the Gulf
of Maine, repeated side rolls have been recorded when whales were near
the bottom, which likely serves to startle prey out of the substrate
for better foraging (Friedlaender et al., 2009). In many locations,
feeding in the water column can vary with time of day, with whales
bottom feeding at night and surface feeding near dawn (Friedlaender et
al., 2009).
Humpback whales are `gulp' or `lunge' feeders, capturing large
mouthfuls of prey during feeding rather than continuously filtering
food, as may be observed in some other large baleen whales
(Ingebrigtsen, 1929). In the Southern Hemisphere, only one style of
foraging (`lunge' feeding) has been reported. When lunge feeding,
whales advance on prey with their mouths wide open, then close their
mouths around the prey and trap them by forcing engulfed water out past
the baleen
[[Page 22309]]
plates. Southern Hemisphere humpback whales forage in the Antarctic
circumpolar current, feeding almost exclusively on Antarctic krill
(Euphausia superba) (Matthews, 1937; Mackintosh, 1965; Kawamura, 1994).
Stomach content analysis from hunted whales taken in sub-tropical
waters and on migratory routes indicated that stomachs were nearly
always empty (Chittleborough, 1965a). Infrequent sightings of feeding
activity and stomach content data suggest that some individuals may
feed opportunistically during the southward migration toward Antarctic
waters (Matthews, 1932; Dawbin, 1956; Kawamura, 1980).
In the Southern Ocean, Antarctic krill tend to be most highly
concentrated around marginal sea ice zones, where they feed on sea ice
algae. As a result, Southern Hemisphere humpback whale distribution is
linked to regions of marginal sea ice (Friedlaender et al., 2006) and
zones of high euphausiid density (Murase et al., 2002), with foraging
mainly concentrated in the upper 100m of the water column (Dolphin,
1987; Friedlaender et al., 2006). There is evidence of a positive
relationship between prey density and humpback whale abundance
(Friedlaender et al., 2006).
Reproduction
The mating system of humpback whales is generally thought to be
male-dominance polygyny, also described as a `floating lek' (Clapham,
1996). In this system, multiple males compete for individual females
and exhibit competitive behavior. Humpback whale song is a long,
complex vocalization (Payne and McVay, 1971) produced by males on the
winter breeding grounds, and also less commonly during migration
(Clapham and Mattila, 1990; Cato, 1991) and on feeding grounds (Clark
and Clapham, 2004b). The exact function has not been determined, but
behavioral studies suggest that song is used to advertise for females,
and/or to establish dominance among males (Tyack, 1981; Darling and
B[eacute]rub[eacute], 2001; Darling et al., 2006). It is widely
believed that, while occasional mating may occur on feeding grounds or
on migration, the great majority of mating and conceptions take place
in winter breeding areas (Clapham, 1996; Clark and Clapham, 2004a).
Breeding in the Northern and Southern Hemisphere populations is out of
phase by approximately 6 months, corresponding to their respective
winter periods.
Sexual maturity of humpback whales in the Northern Hemisphere
occurs at approximately 5-11 years of age, and appears to vary both
within and among populations (Clapham, 1992; Gabriele et al., 2007b;
Robbins, 2007). Average age of sexual maturity in the Southern
Hemisphere is estimated to be 9-11 years. In the Northern Hemisphere,
calving intervals are between 1 and 5 years, though 2-3 years appears
to be most common (Wiley and Clapham, 1993; Steiger and Calambokidis,
2000). Estimated mean calving rates are between 0.38 and 0.50 calves
per mature female per year (Clapham and Mayo, 1990; Straley et al.,
1994; Steiger and Calambokidis, 2000) and reproduction is annually
variable (Robbins, 2007). In the Southern Hemisphere, most information
on humpback whale population characteristics and life history was
obtained during the whaling period. Post-partum ovulation is reasonably
common (Chittleborough, 1965a) and inter-birth intervals of a single
year have occasionally been recorded. This may be a consequence of
early calf mortality; the associated survival rates for annually born
calves are unknown in the Southern Hemisphere.
Humpback whale gestation is 11-12 months and calves are born in
tropical waters (Matthews, 1937). Lactation lasts from 10.5-11 months
(Chittleborough, 1965a), weaning begins to occur at about age 6 months,
and calves attain maternal independence around the end of their first
year (Clapham and Mayo, 1990). Humpback whales exhibit maternally
directed fidelity to specific feeding regions (Martin et al., 1984;
Baker et al., 1990).
The average generation time for humpback whales (the average age of
all reproductively active females at carrying capacity) is estimated at
21.5 years (Taylor et al., 2007). Empirically estimated annual rates of
population increase range from a low of 0 to 4 percent to a maximum of
12.5 percent for different times and areas throughout the range (Baker
et al., 1992; Barlow and Clapham, 1997; Steiger and Calambokidis, 2000;
Clapham et al., 2003a); however, Zerbini et al. (2010) concluded that
any rate above 11.8 percent per year is biologically implausible for
this species.
Natural Mortality
Annual adult mortality rates have been estimated to be 0.040
(standard error (SE) = 0.008) (Barlow and Clapham, 1997) in the Gulf of
Maine and 0.037 (95 percent confidence interval (CI) 0.022-0.056)
(Mizroch et al., 2004) in the Hawaiian Islands populations. In the
Southern Hemisphere, estimates of annual adult survival rates have been
made using photo-identification studies in Hervey Bay, east Australia
(1987-2006), and range between 0.87 and 1.00 (Chaloupka et al., 1999).
Robbins (2007) estimated calf (0-1 year old) survival for humpback
whales in the Gulf of Maine at 0.664 (95 percent CI: 0.517-0.784),
which is low compared to other areas. Barlow and Clapham (1997)
estimated a theoretical calf mortality rate of 0.125 on the Gulf of
Maine feeding ground. Using associations of calves with identified
mothers on North Pacific breeding and feeding grounds, Gabriele (2001)
estimated mortality of juveniles at 6 months of age to be 0.182 (95
percent CI: 0.023-0.518). Survival of calves (6-12 months) and
juveniles (1-5 years) has not been described in detail for the Southern
Hemisphere. Killer whales are likely the most common natural predators
of humpback whales.
Status Review Report
The BRT's status review report compiled the best available
scientific and commercial information on: (1) Population structure of
humpback whales within the North Pacific, North Atlantic, and Southern
Oceans, used to determine whether any populations within these ocean
basins meet the DPS policy criteria; (2) the abundance and trend
information for each DPS; (3) those ESA section 4(a)(1) factors
currently affecting the status of these DPSs; (4) ongoing conservation
efforts affecting the status of these DPSs; and (5) the extinction risk
of each DPS. See the status review report for further information on
the biology and ecology of the humpback whale (Bettridge et al., 2015).
Humpback Whale Subspecies
The BRT reviewed the best scientific and commercial data available
on the humpback whale's taxonomy and concluded that there are likely
three unrecognized subspecies of humpback whale: North Pacific, North
Atlantic, and Southern Hemisphere. In reaching this conclusion, the BRT
considered available life history, morphological, and genetic
information.
Humpback whales routinely make extensive migrations between
breeding and feeding areas within an ocean basin. Despite this
potential for long distance dispersal, there is considerable evidence
that dispersal or interbreeding of individuals from different major
ocean basins is extremely rare and that whales from the major ocean
basins are differentiated by a number of characteristics.
Reproductive Seasonality: Humpback whales breed and calve in July-
[[Page 22310]]
November in the Southern Hemisphere and in January-May in the Northern
Hemisphere (including the Arabian Sea). It is not known if reproductive
seasonality in baleen whales is determined genetically or whether it
results from a learned behavior (migration to a particular feeding
destination) combined with a physiological response to day length.
Behavior: The most obvious behavioral difference is that migrations
to and from high latitudes are in opposite times of the calendar year
for Southern Hemisphere and most Northern Hemisphere populations,
following the difference in reproductive seasonality. A Northern
Hemisphere exception to this migration pattern is found in the Arabian
Sea where a non-migratory population is found. Although these
behavioral differences could be learned, they could also be innate,
genetically determined traits. Seasonality in singing and other mating
behaviors also follows the differences in reproductive seasonality.
Color patterns: Humpback whales in the Southern Hemisphere tend to
have much more white pigmentation on their bodies which is especially
noticeable laterally (Matthews, 1937; Chittleborough, 1965b). This has
been noted in eastern and western Australia, the Coral Sea, and
Oceania, but might not be characteristic of all Southern Hemisphere
populations. Rosenbaum et al. (1995) ranked ventral fluke coloration
patterns from one (nearly all white) to five (nearly all black) and
compared whales from several breeding areas. He found that over 80
percent of humpback whales in eastern and western Australia were in
Category 1, and that less than 10 percent of whales in three breeding
areas in the North Pacific were ranked in that category. Only 36
percent of Southern Hemisphere whales in Colombia were classified in
Category 1, but Colombian whales were still, on average, whiter than
North Pacific whales. A higher frequency of flippers with white dorsal
pigmentations is found in the North Atlantic compared to the North
Pacific (Clapham, 2009).
Genetics: Baker and Medrano-Gonzalez (2002) reviewed the worldwide
distribution of mtDNA haplotypes.\1\ They found three major clades
(groups consisting of an ancestor and all its descendants) with
significant differences among major ocean basins, though there were no
completely fixed differences among these areas. The North Pacific
included only the AE and CD clades, the North Atlantic included only
the CD and IJ clades, and the Southern Oceans included all three. In a
more recent comparison, Jackson et al. (2014) found no shared
haplotypes between the North Pacific and North Atlantic. Based on
patterns of mtDNA variation, Rosenbaum et al. (2009b) estimated an
average migration rate of less than one per generation between the
Arabian Sea and neighboring populations in the southern Indian Ocean,
and Jackson et al. (2014) also estimated generally <1 migrant per
generation among the North Pacific, North Atlantic and Southern
Hemisphere populations. Ruegg et al. (2013) also found a high degree of
genetic differentiation between samples from the North Atlantic and the
Southern Hemisphere.
---------------------------------------------------------------------------
\1\ A mtDNA haplotype is a group of genes, or alleles, that is
maternally inherited; genetic differentiation is generally based on
allele frequency differences between populations, which are measured
by FST or related statistics; FST is a measure
of the genetic distance between populations, or difference in the
allele frequency between two populations.
---------------------------------------------------------------------------
Subspecies Discussion and Conclusions
The BRT considered the possibility that humpback whales from
different ocean basins might reasonably be considered to belong to
different subspecies. Sub-specific taxonomy is relevant to the
identification of DPSs because, under the 1996 DPS policy, the
discreteness and significance of a potential DPS is evaluated with
reference to the taxon (species or subspecies) to which it belongs. In
some cases previous BRTs have determined that sub-specific taxonomy has
a large influence on DPS structure (e.g., southern resident killer
whales--Krahn et al., 2004a)), while in other cases sub-specific
taxonomy has not been relevant (e.g., steelhead trout DPS--Busby et
al., 1996).
Rice (1998) reviewed previous subspecies designations for humpback
whales. Tomilin (1946) named a Southern Hemisphere subspecies (M. n.
lalandii) based on body length, but this length difference was not
substantiated in subsequent studies. The populations around Australia
and New Zealand were described as another subspecies (M. n.
novazelandiae) based on color patterns and length (Ivashin, 1958). Rice
(1998) noted that the statistical ability to classify these proposed
subspecies is ``not quite as high as is customarily required for
division into subspecies'' and that genetic analyses using restriction-
fragment length polymorphisms is not congruent with the proposed
regional division. Rice (1998) therefore recommended that Megaptera
novaeangliae be considered monotypic. As was summarized above, however,
since 1998, additional information has accumulated on the genetic
distinctiveness of different geographic populations of humpback whales,
and some new subspecies have been proposed (Jackson et al., 2014).
One criterion for separation of subspecies is the ability to
differentiate 75 percent of individuals found in different geographic
regions (Reeves et al., 2004). Based on this criterion, differences in
the calendar timing of mating and reproduction could be used to
distinguish close to 100 percent of Northern Hemisphere from Southern
Hemisphere individuals, but it is not known if this is genetically
determined. Based on mtDNA haplotypes that have been identified to
date, haplotype could be used to distinguish 100 percent of North
Pacific from North Atlantic individuals, but some haplotypes from both
ocean basins are shared with the Southern Ocean. Ventral fluke color
patterns can be used to correctly differentiate >80 percent of whales
in eastern and western Australia from the whales in the North Pacific
(Rosenbaum et al., 1995).
The BRT also considered the advice of the Committee on Taxonomy of
the Society for Marine Mammalogy (SMM). The BRT asked the Committee:
``Are humpback whales (Megaptera novaeangliae) that feed in the North
Atlantic, North Pacific, Southern Oceans and Arabian Sea likely to
belong to different sub-species?'' The SMM was asked only for its
scientific opinion on the likelihood of the existence of humpback whale
subspecies and was not asked to comment on the relevance of their
opinion to the identification of DPSs for humpback whales. The SMM
chairman summarized responses from members of the SMM:
The balance of opinion in the SMM Committee on Taxonomy is that
given the evidence on genetics, morphology, distribution and
behavior, if a taxonomic revision of the humpback whale were
undertaken, it is likely that the North Atlantic, North Pacific and
Southern Hemisphere populations would be accorded subspecific
status. Whether the Arabian Sea population would merit recognition
as a subspecies separate from the Southern Hemisphere whales, with
which it is most closely related genetically, is less certain.
However, it is clearly geographically isolated and genetically
differentiated.
Using its structured decision making process (whereby each BRT
member distributed 100 likelihood points among different scenarios),
the BRT considered the likelihood of a single global species with no
subspecies scenario, a three-subspecies scenario (North Atlantic, North
Pacific, and Southern
[[Page 22311]]
Hemisphere), and a four-subspecies scenario (North Atlantic, North
Pacific, Southern Hemisphere, and Arabian Sea). The BRT's allocation of
likelihood points indicates that in the opinion of the BRT, the most
likely scenario is the 3-subspecies scenario.
In October 2014, after the BRT report was completed, the SMM
updated its species and subspecies list to recognize the North
Atlantic, North Pacific, and Southern Hemisphere humpback whale
populations as subspecies: Megaptera novaeangliae kuzira (North
Pacific), M. n. novaeangliae (North Atlantic) and M. n. australis
(Southern Hemisphere) (http://www.marinemammalscience.org/index.php?option=com_content&view=article&id=758&Itemid=340). This
update was based on mtDNA and DNA relationships and distribution, as
described in Jackson et al. (2014). We therefore consider whether the
various humpback whale population segments identified by the BRT
satisfy the DPS criteria of discreteness and significance relative to
the subspecies to which they each belong: North Atlantic, North
Pacific, and Southern Hemisphere subspecies.
Distinct Population Segment Analysis, By Subspecies
North Atlantic
Overview
In the Northern Hemisphere, humpback whales summer in the
biologically productive, northern latitudes and travel south to warmer
waters in winter to mate and calve. Migratory routes and migratory
behavior are likely to be maternally directed (Martin et al., 1984;
Baker et al., 1990). Feeding areas are often near or over the
continental shelf and are associated with cooler temperatures and
oceanographic or topographic features that serve to aggregate prey
(Moore et al., 2002; Zerbini et al., 2006a).
Primary humpback whale feeding areas in the North Atlantic Ocean
range from 42[deg] to 78[deg]N and include waters around Iceland,
Norway, and the Barents Sea in the central and eastern North Atlantic
Ocean, and western Greenland, Newfoundland, Labrador, the Gulf of St.
Lawrence and the Gulf of Maine in the western North Atlantic Ocean.
Known breeding areas occur in the West Indies and, to a much lesser
extent, around the Cape Verde Islands (Katona and Beard, 1990; Clapham,
1993; Palsb[oslash]ll et al., 1997). A relatively small proportion of
whales in the North Atlantic Ocean feed in U.S. waters. The predominant
breeding and calving area lies in the territorial sea of the Dominican
Republic, although whales are also found scattered throughout the rest
of the Antilles and coastal waters of Venezuela. The Silver/Navidad/
Mouchoir Bank complex hosts the largest single breeding aggregation of
humpback whales in the West Indies.
Recently, a few humpback whales have also been found in the
Mediterranean Sea but little is known about humpback whale use of this
region and there is no evidence of a large humpback whale presence
there, either currently or in historical times (Frantzis et al., 2004).
There are also sporadic sightings of humpback whales in a wide range of
places, including waters offshore from the mid-Atlantic and Southeast
United States, in the Gulf of Mexico, and in the waters around Ireland.
Bermuda is a known mid-ocean stopover point for humpback whales on
their northbound migration (Stone et al., 1987).
Discreteness
Genetic studies have identified 25 humpback whale haplotypes in the
western North Atlantic, 12 haplotypes in eastern North Atlantic
samples, and 19 haplotypes in whales that feed during the summer in the
Gulf of Maine (Palsb[oslash]ll et al., 1995; Larsen, 1996a; Rosenbaum
et al., 2002). Humpback whales in the North Atlantic Ocean appear to
have higher haplotype diversity than humpback whales in the North
Pacific Ocean (Baker and Medrano-Gonz[aacute]lez, 2002). Haplotype
diversity is lowest in populations around Norway and Iceland and higher
around the northwestern feeding areas off Greenland, Gulf of St.
Lawrence and Gulf of Maine (Baker and Medrano-Gonz[aacute]lez, 2002).
Observed nucleotide diversity is also higher in the North Atlantic than
in the North Pacific (Baker and Medrano-Gonz[aacute]lez, 2002).
Whales that breed in the West Indies and Cape Verde Islands co-
mingle in North Atlantic feeding areas. Palsboll et al. (1995) and
Valsecchi et al. (1997) found significant (FST= ~0.04)
levels of mtDNA and nuclear genetic variation among North Atlantic
feeding areas, suggesting there are genetically distinct breeding areas
(there are no published genetic studies directly comparing whales in
the West Indies breeding areas with whales in the Cape Verde Islands
breeding areas). Photo-ID and genetic matching data suggest no evidence
for substructure within the West Indies breeding population (reviewed
by Fleming and Jackson (2011)), so this differentiation likely is due
to genetic divergence between the West Indies and another North
Atlantic breeding population, likely associated with the Cape Verde
Islands or possibly other areas in the Northeastern Atlantic.
Most of the humpback whales on the western North Atlantic feeding
grounds (Gulf of Maine, Gulf of St. Lawrence, West Greenland, and
eastern Canada) come from the well-studied West Indies breeding ground
(approximately 90 percent) (Clapham et al., 1993; Mattila et al.,
2001). Some of the whales from the Iceland and Norway feeding grounds
also come from the West Indies breeding grounds, but genetic evidence
suggests that most whales from the Iceland and Norway feeding grounds
migrate from some other breeding ground. The location of possible
breeding grounds of these whales is not well understood, but Clapham et
al. (1993) suggest it may be in the eastern tropical Atlantic Ocean.
Sighting histories of the Cape Verde Islands whales link them to
feeding grounds in the waters off Iceland or Norway (Katona and Beard,
1990; Jann et al., 2003), and the Cape Verde Islands is the only
candidate breeding ground from historical whaling records. However,
current studies show only a small number of whales in the Cape Verde
Islands--far fewer than the non-West Indies whales known to exist in
the northeastern Atlantic. The Cape Verde Islands may therefore be part
of a larger breeding area, or there may be a third separate breeding
area that is as yet undiscovered (Charif et al., 2001; Reeves et al.,
2002). The possibility of a third breeding area unassociated with the
Cape Verde Islands is supported by nuclear DNA, as there is a
significant degree of heterogeneity in nuclear DNA among populations in
the western, central (Iceland) and eastern (Norway) North Atlantic
feeding grounds (Larsen, 1996b).
The BRT concluded there are two populations of humpback whales in
the North Atlantic Ocean meeting the discreteness criteria under the
DPS policy--one with breeding grounds in the West Indies and another
with breeding grounds near Cape Verde Islands and a possible associated
breeding area, likely off Northwest Africa. In particular, whales from
the West Indies and the Cape Verde Islands breeding grounds are
discrete based on: (1) No photographic matches between individuals
using the West Indies and Cape Verde Islands areas (acknowledging that
there is a large sample size for the West Indies breeding grounds and a
small sample size for the Cape Verde Islands breeding grounds); (2)
occupation of both breeding grounds at the same time; (3) evidence from
19th century whaling data of a historically larger population at the
Cape Verde Islands than exists today; and (4) genetic
[[Page 22312]]
heterogeneity in the feeding grounds indicating that the West Indies is
not the only breeding ground. Because the Cape Verde Islands cannot
account for the abundance of whales estimated from the eastern North
Atlantic feeding grounds that are not documented using the West Indies,
there must be an additional breeding area, likely near Northwest
Africa, and possibly associated with the Cape Verde Islands.
Significance
The West Indies breeding ground includes the Atlantic margin of the
Antilles from Cuba to northern Venezuela, with the Silver/Navidad/
Mouchoir Bank complex comprising a major breeding ground. Whales from
this breeding ground have a feeding range that primarily includes the
Gulf of Maine, eastern Canada, and western Greenland. While many West
Indies whales also use feeding grounds in the central North Atlantic
(Iceland) and eastern North Atlantic (Norway), many whales from these
feeding areas appear to winter in another location.
The BRT concluded this discrete group of whales is significant to
the North Atlantic subspecies due to the significant gap in the
breeding range that would occur if it were extirpated. Loss of the West
Indies population would result in the loss of humpback whales from all
of the western North Atlantic breeding grounds (Caribbean/West Indies)
and feeding grounds (United States, Canada, Greenland).
The Cape Verde Islands/Northwest Africa breeding grounds include
waters surrounding the Cape Verde Islands as well as an undetermined
breeding area in the eastern tropical Atlantic, which may be more
geographically diffuse than the West Indies breeding ground. The
population of whales breeding in Cape Verde Islands plus this unknown
area likely represents the remnants of a historically larger population
breeding around Cape Verde Islands and Northwest Africa (Reeves et al.,
2002). There is no known overlap in breeding range with North Atlantic
humpback whales that breed in the West Indies. As noted above, the BRT
determined the population was discrete from the West Indies population
based upon genetic evidence that suggests a second breeding ground
occupied by whales that feed primarily off Norway and Iceland. It also
determined that this population was significant to the North Atlantic
subspecies because of the gap that would exist in the breeding range if
it were extirpated.
We agree with the BRT and we therefore identify two DPSs of the
North Atlantic humpback whale subspecies: (1) West Indies DPS; and (2)
Cape Verde Islands/Northwest Africa DPS.
North Pacific
Overview
Humpback whales in the North Pacific migrate seasonally from
northern latitude feeding areas in summer to low-latitude breeding
areas in winter. Feeding areas are dispersed across the Pacific Rim
from California, United States, to Hokkaido, Japan. Within these
regions, humpback whales have been observed to spend the majority of
their time feeding in coastal waters. Breeding areas in the North
Pacific are more geographically separated than the feeding areas and
include: (1) Regions offshore of mainland Central America; (2)
mainland, Baja Peninsula and the Revillagigedos Islands, Mexico; (3)
Hawaii; and (4) Asia including Ogasawara and Okinawa Islands and the
Philippines. About half of the humpback whales in the North Pacific
Ocean breed and calve in the U.S. waters off Hawaii; more than half of
North Pacific Ocean humpback whales feed in U.S. waters.
Humpback whales in the North Pacific rarely move between these
breeding regions. Strong fidelity to both feeding and breeding sites
has been observed, but movements between feeding and breeding areas are
complex and varied (Calambokidis et al., 2008). An overall pattern of
migration has recently emerged. Asia and Mexico/Central America are the
dominant breeding areas for humpback whales that migrate to feeding
areas in lower latitudes and more coastal areas on each side of the
Pacific Ocean, such as California and Russia. The Revillagigedo
Archipelago and Hawaiian Islands are the primary winter migratory
destinations for humpback whales that feed in the more central and
higher latitude areas (Calambokidis et al., 2008). However, there are
exceptions to this pattern, and it seems that complex population
structure and strong site fidelity coexist with lesser known, but
potentially high, levels of plasticity in the movements of humpback
whales (Salden et al., 1999).
Discreteness
Baker et al. (2013) recently analyzed genetic variation in a large
(n = 2,193) sample of whales from 8 breeding and 10 feeding regions
within the North Pacific. The 8 possible breeding regions included the
Philippines, Okinawa, Ogasawara, Hawaii, Revillagigedo, Baja
California, the Mexican mainland coast, and Central America. In
addition, results from Calambokidis et al. (2008) indicate the
existence of at least one additional breeding area whose location has
not been identified. Overall, the level of genetic divergence among
breeding areas at the mtDNA control region was substantial
(FST = 0.093). Pairwise estimates of divergence among
breeding areas ranged from none (FST = ~0.000; Philippines
vs Okinawa) to very high (FST > 0.2 for Hawaii versus
Okinawa and Philippines, and Hawaii versus Central America). In
addition to little divergence between Okinawa and the Philippines, the
three Mexican areas (mainland coast, Baja California, and
Revillagigedos Islands) were not significantly differentiated. In
contrast to the mtDNA variation, the breeding areas were less strongly
(but still significantly) differentiated at 10 nuclear microsatellite
loci (FST = 0.006), suggesting the possibility of some male
mediated gene flow among breeding areas. After application of an
adjustment for diversity (Hedrick, 2005; Baker et al., 2013), the
effect size increased to F'ST = 0.0128 and F'ST =
0.0214 for feeding and breeding grounds, respectively. Of these nine
areas, two are likely migratory routes to other locations and might
therefore not be primary breeding grounds: the waters off Baja
California and the Ogasawara Islands.
Similarly, some humpback whales migrating to the Okinawa Islands
pass by the Ogasawara Islands, and the Ogasawara Islands are also
thought likely to be along the migration route to the unidentified
breeding area that was described in Calambokidis et al. (2008). Because
of the existence of an unidentified breeding area, the population
structure of the western North Pacific populations proved more
challenging. Humpback whales in Okinawa were not significantly
different in either mtDNA or nDNA from whales in the Philippines (Baker
et al., 2013). Mitochondrial DNA and nDNA markers from the pooled
populations from Okinawa and the Philippines populations differ
significantly from those of humpback whales in the Ogasawara Islands
and all other populations (Baker et al., 2013). However, given the
likelihood that Ogasawara whales are only passing through en route to
two or more migratory destinations, the BRT members concluded that
there are likely two discrete populations consisting of an Okinawa/
Philippines population and an unknown breeding group, both using the
Ogasawara area as a migratory corridor. Given the uncertainty about the
location of the other breeding ground, and the use of a common
migratory corridor by the known group
[[Page 22313]]
and the unknown group, we have decided to include the unknown breeding
group in the Okinawa/Philippines population. We refer to this combined
discrete population as the Western North Pacific population.
The Hawaii population of humpback whales is separated by the
greatest geographic distance from neighboring populations and was
significantly different from other populations in both frequencies of
mtDNA haplotypes and nDNA (microsatellite) alleles (Baker et al.,
2013). The BRT therefore concluded that whales wintering in Hawaii
constitute a discrete population.
In Mexico, available genetic and demographic studies indicate that
humpback whales migrating to mainland Mexico and to the Revillagigedos
Islands pass by the tip of Baja California. The BRT therefore concluded
that humpback whales off Baja California should not be considered a
discrete population. Further, the mainland population in Mexico does
not differ significantly from the Revillagigedos population in its
mtDNA haplotype frequencies (Baker et al., 2013). Photo-identification
studies also indicate considerable movement of individuals between
mainland and offshore island breeding areas in Mexico (Calambokidis et
al., 2008). The BRT therefore concluded that mainland Mexico and the
Revillagigedos populations are a single Mexico population discrete from
all other populations.
In the eastern North Pacific, humpback whales in Central America
have a unique mtDNA signature, as reflected in the frequencies of
haplotypes (Baker et al., 2008a; Baker et al., 2008b). This frequency
composition is significantly different from that in whales from all
other breeding grounds in the North Pacific. The BRT concluded that
humpback whales in Central America are a discrete population.
Thus while the BRT concluded there are five breeding populations of
humpback whales in the North Pacific that meet the criteria for being
discrete under the DPS Policy guidelines, we propose to identify four:
(1) Western North Pacific (includes Okinawa/Philippines and the
unidentified breeding area in the western North Pacific); (2) Hawaii
(3) Mexico (includes mainland Mexico and the Revillagigedos Islands);
and (4) Central America.
Significance
In evaluating whether any discrete population differed in its
ecological characteristics from others, the BRT weighted ecological
differences among feeding areas more heavily than among breeding areas,
since it concluded that the ecological characteristics of humpback
whales in their breeding ranges were largely similar among populations.
In contrast, the BRT concluded whales largely foraging in different
large marine ecosystems inhabit different ecological settings and that
this is relevant in evaluating the significance of these populations.
The BRT stated that, within the North Pacific, the Okinawa/Philippines,
Hawaii, Mexico, and Central America populations tend to feed in
different marine ecosystems, although there is some overlap. The
Western North Pacific population, which feeds in the Western Bering Sea
(the Okinawa/Philippines population) and the Aleutian Islands (the
unidentified breeding population), feeds in an ecosystem entirely
different from the others in the North Pacific. The BRT also noted that
the Central America population's breeding habitat is ecologically
unique for the species as it is the only area where documented
geographic overlap of populations that feed in different hemispheres
occurs, potentially creating a conduit for genetic exchange between the
two hemispheres. While a minority of members believed that this was an
example of temporal and geographic overlap rather than a unique
ecological setting, we conclude that the Central America population is
significant to the ocean-basin based North Pacific subspecies because
of its ecologically unique breeding habitat. We agree with the BRT that
the Western North Pacific and Central America populations occupy unique
ecological settings (unique breeding and feeding grounds for the
Western North Pacific, unique breeding habitat for the Central America
population), and therefore, they both are significant to the North
Pacific subspecies.
The BRT noted that in the North Pacific Ocean, loss of the Okinawa/
Philippines population would likely result in a significant gap in the
North Pacific feeding range as these individuals are the only breeding
population to migrate primarily to Russia, and loss of this population
would therefore result in a loss of feeding range along the Russian
coast. We concur with this conclusion, but because we have combined the
unknown breeding group that feeds in the Aleutian Islands with the
Okinawa/Philippines population, we need to assess whether this combined
Western North Pacific population is significant to the ocean-basin
based North Pacific subspecies. We conclude that the loss of the
Western North Pacific population would result in a significant gap in
the range of the North Pacific subspecies because if loss of the
Okinawa/Philippines population would result in a significant gap, then
the loss of a larger combined population would, too. The loss of
humpback whales from the Hawaii breeding population would result in
loss of humpbacks from the Hawaiian Islands, and this would represent a
significant gap in the range of the North Pacific subspecies. We
conclude that the Western North Pacific and the Hawaii populations both
meet the significance criterion of the DPS Policy because loss of these
populations would result in a significant gap in the range of the North
Pacific subspecies. While the loss of the Mexico or Central America
populations would not result in a significant gap in the range of their
feeding grounds because their feeding grounds overlap, it would result
in a significant gap in their breeding grounds, and therefore, we
consider the Mexico and Central America populations also to be
significant to the North Pacific subspecies.
The BRT discussed whether there was evidence for marked genetic
divergence among any of the discrete populations. Although there was
not clear agreement on the definition of ``marked,'' the BRT concluded
that strong patterns of genetic differentiation in mtDNA sequence among
most of the North Pacific breeding populations indicated marked genetic
divergence, consistent with the conclusions in Baker et al. (2013). The
overall level of differentiation among breeding populations within the
North Pacific (FST = 0.09) was similar to the level of
divergence among ocean basins and is consistent with a relatively high
degree of divergence of these populations. Further, in reviewing Baker
et al. (2013), all populations that we have identified as discrete in
the North Pacific are strongly differentiated from each other at the p-
value \2\ of 0.01 level or better, except for the Central America/
Philippines pair, which are differentiated from each other at p-value
of 0.05. Therefore, we agree with the BRT and conclude that all four of
the discrete populations we have identified in the North Pacific
(Western North Pacific, Hawaii, Mexico, and Central
[[Page 22314]]
America) are significant to the North Pacific subspecies because of
marked genetic differentiation.
---------------------------------------------------------------------------
\2\ The p-value is the probability of obtaining a test statistic
result at least as extreme as the one that was actually observed,
assuming that the null hypothesis is true; a small p-value
(typically <= 0.05) indicates strong evidence against the null
hypothesis; a null hypothesis is a general statement or default
position that there is no relationship between two measured
phenomena.
---------------------------------------------------------------------------
Although the petitioned North Pacific population could also satisfy
the discreteness and significance criteria of the DPS Policy, there are
other plausible and scientifically supported approaches to dividing the
species into DPSs. We conclude that our modification of the BRT's
approach for humpback whales in the North Pacific (i.e., combining the
unknown breeding group with the Okinawa/Philippines population) is more
appropriate to further the purposes of the ESA because it represents a
more risk-averse approach with respect to the unknown breeding group.
As discussed above, identification of the Western North Pacific,
Hawaii, Mexico, and Central America populations as DPSs is supported by
the best available scientific and commercial information. We are
exercising the discretion afforded to us as an expert agency charged
with administering the ESA in the face of conflicting proposals (i.e.,
petitions to delist North Pacific and Central North Pacific
populations) to recognize these four populations as DPSs. Therefore, we
will evaluate the status of each of these four DPSs in the North
Pacific rather than recognizing a single North Pacific DPS and
evaluating its combined status (i.e., the approach offered by the
Hawaii Fishermen's Alliance). The petition to delineate the North
Pacific population as a DPS and ``delist'' it is therefore denied
(i.e., the petitioned action is not warranted). The petitioned Central
North Pacific population is the same as the Hawaii DPS we have
identified; therefore, we will evaluate the status of the Hawaii DPS to
determine whether it is warranted for listing.
The following populations of the North Pacific humpback whale
subspecies meet the discreteness and significance criteria for being a
DPS under the DPS Policy: (1) Western North Pacific; (2) Hawaii; (3)
Mexico; and (4) Central America.
Southern Hemisphere
Overview
There are at least eleven breeding grounds identified in the
Southern Hemisphere at temperate latitudes: Brazil, Gabon and central
West Africa, Mozambique, the Comoros Archipelago, Madagascar, West
Australia, East Australia, New Caledonia, Tonga, French Polynesia, and
the southeastern Pacific, (Stevick et al., 2006; Zerbini et al., 2006b;
Engel and Martin, 2009; IWC, 2011). The Arabian Sea breeding ground is
also at a temperate latitude and, while it is in the Northern
Hemisphere, we discuss it here because we determined earlier that it
was part of the Southern Hemisphere subspecies of the humpback whale.
The primary mating/calving ground of humpback whales in the western
South Atlantic Ocean is the coast of Brazil. This population migrates
to feeding grounds located east of the Scotia Sea near South Georgia
and the South Sandwich Archipelagos (Stevick et al., 2006; Zerbini et
al., 2006b; Engel et al., 2008; Engel and Martin, 2009; Zerbini et al.,
2011). The winter breeding distribution of humpback whales in the
southwestern Atlantic (June to December) is concentrated around the
Abrolhos Bank region in Brazil (15-18[deg] S.) and 500 km north, along
the north coast of Bahia State and Espirito Santo State (Rossi-Santos
et al., 2008) and near Salvador and Recife.
A humpback whale winter breeding and calving ground is located off
central western Africa between ~6[deg] S. and ~6[deg] N. in the eastern
Atlantic. Periods of peak abundance are found between July and
September, with some whales still present as late as December and
January in Angola, Gabon and S[atilde]o Tom[eacute] (Weir, 2007). The
Gabon/Southwest Africa region appears to serve a variety of purposes
with some individual whales remaining in the area through the year
while some use the area for feeding and others for mating (Bettridge et
al., 2015).
At least three winter breeding aggregations of humpback whales have
been suggested in the southwestern Indian Ocean from historical whaling
records and contemporary surveys (Wray and Martin, 1983; Best et al.,
1998). One is associated with the mainland coastal waters of
southeastern Africa, extending from Mozambique (24[deg] S., Findlay et
al., 1994) to as far north as Tanzania and southern Kenya (Wamukoya et
al., 1996; Berggren et al., 2001; O'Connor et al., 2009). The second is
found in the coastal waters of the northern Mozambique Channel Islands
(Comoros Archipelago) and the southern Seychelles (Bettridge et al.,
2015). The third is associated with the coastal waters of Madagascar
(15-25[deg] S.), best described in Antongil Bay on the east coast
(Rosenbaum et al., 1997).
At least three migratory pathways to Antarctic summer feeding
grounds in this region have been proposed using a compilation of data
from surveys, whaling and acoustic records and sightings (Best et al.,
1998). Humpback whale wintering grounds and coastal migratory routes in
the eastern Indian Ocean are located between 15-35[deg] S. along the
west coast of Australia, with major calving grounds occurring in the
Kimberley Region (15-18[deg] S.) and resting areas on the southern
migration at Exmouth Gulf (21[deg] S.) and at Shark Bay (25[deg] S.)
(Bannister and Hedley, 2001; Jenner et al., 2001).
Humpback whales along the east coast of Australia are thought to
breed primarily in waters inside the Great Barrier Reef (16-21[deg] S.)
(Chittleborough, 1965; Simmons and Marsh, 1986) and are seen as far
north as Murray Island at ~10[deg] S. (Simmons and Marsh, 1986).
Discovery marks and satellite telemetry suggest east Australian whales
feed in a broad swath of the Antarctic between 100[deg] E. and 175[deg]
W., or that they frequent at least two feeding regions, one due south
of eastern Australia stretching to the east beneath New Zealand, and
one south of west Australia at ~100[deg] E. and accessed via migration
through Bass Strait.
The longitudinal distribution boundaries of humpback whales
wintering in Oceania lie between ~160[deg] E. (west of New Caledonia)
and ~120[deg] W. (east of French Polynesia) and latitudinally between
0[deg] and 30[deg] S. (Reeves et al., 1999), a range that includes
American Samoa (United States), the Cook Islands, Fiji, French
Polynesia (France), Republic of Kiribati, Nauru, New Caledonia
(France), Norfolk Island, New Zealand, Niue, the Independent State of
Samoa, Solomon Islands, Tokelau, Kingdom of Tonga, Tuvalu, Vanuatu,
Wallis and Futuna (France).
The wintertime breeding distribution of humpback whales in the
southeastern Pacific (May to November) includes the coastal waters
between Panama and northern Peru, with the main wintering areas
concentrated in Colombia (Gorgona Island, M[aacute]laga Bay and
Tribug[aacute] Gulf), Panama, and Ecuador. Low densities of whales are
also found around the Gal[aacute]pagos Islands (F[eacute]lix et al.,
2006b), and coastal sightings have been made as far north as Costa Rica
(Coco Island and Golfo Dulce, 8[deg] N.) (Acevedo and Smultea, 1995;
May-Collado et al., 2005). In the summer months, these whales migrate
to feeding grounds located in waters off southern Chile, the Magellan
Strait, and the Antarctic Peninsula (May-Collado et al., 2005;
F[eacute]lix et al., 2006b; Acevedo et al., 2008).
Sightings and survey data suggest that humpback whales in the
Arabian Sea are primarily concentrated in the shallow near-shore areas
off the coast of Oman, particularly in the Gulf of Masirah and Kuria
Muria Islands regions (Minton, 2004); sightings and strandings suggest
a population range that encompasses the northern Gulf of
[[Page 22315]]
Aden, the Balochistan coast of Pakistan, and western India and Sri
Lanka, with occasional sightings on the Sistan and Baluchistan coasts
of Iran, and also Iraq (Al Robaae, 1974; Braulik et al., 2010). Photo-
identification re-sightings suggest humpback whales move seasonally
between the Dhofar region (Kuria Muria Islands) in winter and the Gulf
of Masirah to the north in summer, with similar re-sighting rates
between and within regions (Minton et al., 2010b).
Despite extensive comparisons of photo-identification catalogues
and genotyped individuals between Oman and the other Indian Ocean
catalogues and genetic datasets, no matches have been detected between
regions (Pomilla et al., 2006; Minton et al., 2010a). Humpback whales
from this region carry fewer and smaller barnacles than Southern
Hemisphere whales, and do not exhibit the white oval scars indicative
of cookie cutter shark (Isistius brasiliensis) bites, a feature
commonly seen on some Southern Hemisphere humpback whales (Mikhalev,
1997).
Connections between the Arabian Sea population with the other
Northern Hemisphere populations are highly unlikely as there is no
accessible northward passage from the Arabian Sea. Furthermore, there
are no mitochondrial DNA haplotypes or song patterns shared with North
Pacific humpback whales (Whitehead, 1985; Rosenbaum et al., 2009);
thus, on current evidence, and in the absence of comparisons with far
western North Pacific humpbacks, it appears that whales from these
populations have no recent biological connectivity. Analysis of fetal
lengths in pregnant females killed by Soviet whalers clearly indicate
that this population exhibits a Northern Hemisphere reproductive cycle,
with births occurring in the boreal winter (Mikhalev, 1997).
Discreteness
Olavarr[iacute]a et al. (2007) analyzed patterns of mtDNA control
region variation obtained from 1,112 samples from 6 breeding grounds in
the South Pacific: New Caledonia, Tonga, Cook Islands, eastern
Polynesia, Colombia, and Western Australia. Of these areas, the samples
from Colombia were most differentiated (FST = 0.06--0.08 in
pairwise comparison to other areas). Pairwise divergence among the
other areas was lower (FST = 0.01--0.05). All pairwise
comparisons were statistically >0, however, and indicated a lack of
free exchange among these breeding areas. Levels of haplotype diversity
were generally very high (0.90--0.97). Rosenbaum et al. (2009)
conducted a similar study of breeding areas in the Southern Atlantic
and Western Indian Oceans, including the coastal areas of Brazil,
Southwestern Africa, and Southeastern Africa. Levels of differentiation
among these are statistically significant but relatively low, with
FST ranging from 0.003 (among two Southwestern African
locations) to 0.017 (between Brazil and Southeastern Africa). Although
there was some detectable differentiation among samples from
Southwestern and Southeastern African coastal locations (B1/B2 and C1/
C2/C3 International Whaling Commission (IWC) stocks, respectively), the
levels of divergence within these areas were very low (FST =
0.003-0.009 within the ``B'' stock and 0.002-0.005 within the ``C''
stock). The estimated number of migrants per generation was 26 between
Brazil and Southwestern Africa, and 33 between Southwestern and
Southeastern Africa.
A report on an IWC workshop devoted to Southern Hemisphere stock
structure issues (IWC, 2011) recognizes at least seven ``breeding
stocks'' associated with low-latitude, winter breeding grounds and, in
some cases, migratory corridors. These seven breeding stocks are
referred to alphabetically, from A to G, to distinguish them from the
six management areas on feeding grounds of the Antarctic, referred to
as Areas I-VI. The current breeding stock designations are southwestern
Atlantic (A), southeastern Atlantic (B), southwestern Indian Ocean (C),
southeastern Indian Ocean (D), southwestern Pacific (E), Oceania (E and
F) and southeastern Pacific (G). These designations have been
subdivided to reflect improved understanding of substructure within
some of these regions: Gabon (B1) and Southwest Africa (B2) in the
southeastern Atlantic; Mozambique (C1), the Comoros Archipelago (C2),
Madagascar (C3) and the Mascarene Islands (C4) in the southwestern
Indian Ocean, east Australia (E1), New Caledonia (E2), Tonga (E3), the
Cook Islands (F1) and French Polynesia (F2) in the southwestern Pacific
and Oceania. The IWC has also chosen to include in this assessment, a
year-round population of humpback whales found in the Arabian Sea,
north of the equator in the northern Indian Ocean (formerly referred to
as breeding stock X).
The BRT noted that the magnitude of mitochondrial DNA
differentiation (as measured by FST) was generally lower
among Southern Hemisphere breeding areas than it is in the Northern
Hemisphere, indicating greater demographic connectivity among these
areas. Even so, significant differentiation was present among major
breeding areas, and the estimated number of migrants/generation among
areas was small compared to the estimated sizes of the populations.
The BRT members concluded that the seven breeding stocks of
humpback whales currently formally recognized by the IWC in the
Southern Hemisphere meet the criteria for being discrete populations
under the DPS Policy guidelines, except that they agreed that the
dividing line between IWC stocks E and F was between eastern Australia
and Oceania (defined here to include New Caledonia, Tonga, Samoa,
American Samoa, and French Polynesia), as there are large differences
in the rates of recovery between these two regions, indicating they are
demographically independent. Breeding populations in New Caledonia and
east Australia are separate, but some overlap between the populations
occurs: some whales bound for New Caledonia use the same migratory
pathways as some whales headed past east Australia. There was consensus
among the BRT to divide the Southern Hemisphere into seven discrete
populations: Brazil, Gabon/Southwest Africa, Southeast Africa/
Madagascar, West Australia, East Australia, Oceania (including New
Caledonia, Tonga, Cook Islands, Samoa, American Samoa and French
Polynesia), and Southeastern Pacific (Colombia and Ecuador). We agree
with the BRT's conclusions, based on the significant mitochondrial DNA
differentiation among major breeding populations.
With regard to the Arabian Sea population, nuclear and
mitochondrial DNA diversity of humpback whales from Oman (up to 47
individuals sampled) is the lowest among all breeding grounds (Pomilla
et al., 2006; Olavarr[iacute]a et al., 2007; Rosenbaum et al., 2009).
Mitochondrial DNA analysis revealed only eight distinct haplotypes,
half of which are exclusive to Oman (not detected on other breeding
grounds, Pomilla et al., 2006). Haplotype diversity at the mtDNA
control region is markedly lower than in other populations (0.69 vs
0.90-0.98 for Southern Hemisphere populations and 0.84 for North
Pacific populations) (Olavarr[iacute]a et al., 2007; Rosenbaum et al.,
2009; Baker et al., 2013).
Genetic data (nuclear microsatellites and mitochondrial control
region) and fluke pigmentation markings indicate that the Arabian Sea
breeding population is significantly differentiated from Southern
Indian Ocean breeding grounds (Rosenbaum et al., 2009). Nuclear genetic
analysis suggests that this population is the most strongly and
significantly differentiated in all
[[Page 22316]]
comparisons among other Indian Ocean and South Atlantic breeding
populations (pair-wise FST range between Oman and Southern
Indian Ocean breeding populations = 0.38-0.48) (Pomilla et al., 2006).
Levels of mitochondrial DNA differentiation between Oman and other
Indian Ocean breeding grounds are around ten times higher than among
the other breeding grounds (pair-wise FST range between Oman
and other Indian Ocean breeding populations 0.11-0.15) (Rosenbaum et
al., 2009).
The BRT concluded, and we agree, that the Arabian Sea population is
discrete from all other populations because of its low haplotype
diversity compared to Southern Hemisphere and North Pacific
populations, its differentiation in mtDNA and nDNA markers, and fluke
pigmentation differences between whales in the Arabian Sea and in the
Southern Indian Ocean.
Significance
The BRT noted that, within the Southern Hemisphere, most breeding
populations feed in the same Antarctic marine ecosystem. One exception
is the Brazil population, which feeds north of 60[deg] S. in the South
Georgia and South Sandwich Islands area (IWC, 2011). In addition to
feeding in the Antarctic system, the Gabon/Southwest Africa population
may also feed along the west coast of South Africa in the Benguela
Current, but this is uncertain (IWC, 2011). Like the Central America
population, the Southeastern Pacific breeding population may also be
ecologically unique as it is the only population in the Southern
Hemisphere to occupy an area also used by a Northern Hemisphere
population. We conclude that the Brazil, Gabon/Southwest Africa, and
Southeastern Pacific populations occupy unique ecological settings and
are therefore significant to the Southern Hemisphere subspecies of the
humpback whale.
For the Southern Hemisphere, determination of feeding range is more
difficult since Antarctic feeding areas are less well studied and fewer
connections between breeding and feeding populations have been made.
However, some populations such as Brazil, Southwest Africa, Southeast
Africa, and the Southeastern Pacific are believed to have fairly
discrete and non-overlapping feeding areas, suggesting that if any of
these feeding areas were lost it would, in combination with the lost
breeding area, result in a significant gap in the range. We conclude,
therefore, that the Brazil, Gabon/Southwest Africa, Southeast Africa/
Madagascar, and Southeastern Pacific populations are significant to the
Southern Hemisphere subspecies of the humpback whale because their loss
would result in significant gaps in the range of the Southern
Hemisphere subspecies. Further, we believe that the loss of the West
Australia, East Australia, and Oceania populations would also result in
significant gaps in the ranges of the Southern Hemisphere subspecies
because their non-overlapping breeding ranges are quite extensive.
In the Southern Hemisphere, the Southeastern Pacific population is
the only breeding population that contains a genetic signal from
Northern Hemisphere populations, giving it a unique genetic signature
within the Southern Hemisphere (Baker et al., 1993; Baker and Medrano-
Gonz[aacute]lez, 2002). It is also the most divergent of any of the
Southern Hemisphere populations (Olavarr[iacute]a et al., 2007). In
addition, individuals in this region are morphologically distinct as
they have darker pectoral fin coloration than other individuals in the
Southern Hemisphere (Chittleborough, 1965), although the genetic basis
for this trait is not known. Nonetheless, a majority of the BRT
concluded that the Southeastern Pacific population was sufficiently
differentiated so as to differ `markedly' in its genetic
characteristics from other Southern Hemisphere populations. In
contrast, all other Southern Hemisphere populations were characterized
by generally low levels of differentiation among them, consistent with
demographically discrete populations but not necessarily with marked
genetic divergence associated with long-term isolation
(Olavarr[iacute]a et al., 2007; Rosenbaum et al., 2009). We conclude
that the Southeastern Pacific population of the humpback whale is
significant to the Southern Hemisphere population of the humpback whale
because it differs markedly in its genetic characteristics from other
Southern Hemisphere populations. We conclude that each of the seven
discrete Southern Hemisphere populations (Brazil, Gabon/Southwest
Africa, Southeast Africa/Madagascar, West Australia, East Australia,
Oceania, and Southeastern Pacific) satisfies at least one significance
factor of the DPS Policy, and, therefore, we consider them to be DPSs.
The Arabian Sea population persists year-round in a monsoon driven
tropical ecosystem with highly contrasting seasonal wind and resulting
upwelling patterns. The BRT therefore concluded that this population
persists in a unique ecological setting. The Arabian Sea population
segment does not migrate extensively, but instead feeds and breeds in
the same geographic location. No other humpback whale populations
occupy this area and hence, a loss of the Arabian Sea population would
result in a significant gap in the range of the Southern Hemisphere
subspecies. The BRT also concluded that the Arabian Sea population
differs markedly in its genetic characteristics from other populations
in the Indian Ocean and worldwide. The degree of genetic
differentiation at multiple genetic markers between this population and
other populations is similar to or greater than the degree of
divergence among the North Pacific, North Atlantic, and Southern
Hemisphere areas. The BRT unanimously concluded that the Arabian Sea
population would be considered a DPS under any global taxonomic
scenario, due to its marked genetic divergence from all other
populations and unique ecological setting. We agree that the Arabian
Sea population occupies a unique ecological setting, its loss would
result in a significant gap in the range of the Southern Hemisphere
subspecies, and it differs markedly in its genetic characteristics from
other populations. Therefore, it meets the significance criterion of
the DPS policy, and we identify the Arabian Sea population as a DPS.
Extinction Risk Assessment
The BRT discussed the relationship between population size and
trend and extinction risk, citing relevant literature on small
population size, environmental and demographic stochasticity, genetic
effects, catastrophes, and extinction risk (e.g., Franklin, 1980;
Soul[eacute], 1980; Gilpin and Soul[eacute], 1986; Allendorf et al.,
1987; Goodman, 1987; Mace and Lande, 1991; Frankham, 1995; Lande, 1998;
Lynch and Blanchard, 1998; Lynch and Lande, 1998; Frankham, 1999; Brook
et al., 2006; Mace et al., 2008) and concluding that population size
criteria similar to those described in Mace et al. (2008)
(International Union for Conservation of Nature and Natural Resources
(IUCN) Red List criteria) could be considered carefully but not used as
the sole criterion for evaluating extinction risk. The criteria the BRT
considered are that a DPS with a total population size >2,000 was not
likely to be at risk due to low abundance alone, a DPS with a
population size <2,000 would be at increasing risk from factors
associated with low abundance (and the lower the population size, the
greater the risk), a DPS with a population size <500 would be at high
risk due to low abundance, and a DPS with a population size <100 would
be at extremely high risk due to
[[Page 22317]]
low abundance. But again, this was not the sole criterion considered by
the BRT, as the BRT also considered how any of the factors (or threats)
listed under ESA section 4(a)(1) contribute to the extinction risk of
each DPS now and in the foreseeable future. Demographic factors that
cause a species to be at heightened risk of extinction, alone or in
combination with other threats under section 4(a)(1), are considered
under ESA Factor E--other natural or manmade factors affecting the
continued existence of the species. Ultimately, the BRT considered both
the abundance and trend information and the threats to each DPS before
making its conclusions on overall extinction risk for each DPS.
The BRT considered abundance and trend information and categorized
each DPS' abundance as described above and indicated whether the
population trend was increasing strongly, increasing moderately,
stable/little trend, or declining. The BRT included an ``unknown''
category where data were not sufficient to detect a trend. To express
uncertainty in abundance or trend information for any DPS, the BRT
categorized abundance and trend in more than one category. As noted
above, while NMFS' 1991 Humpback Whale Recovery Plan recommended that
populations grow to at least 60 percent of their historical (pre-
hunting) abundance to be considered recovered, it did not identify
specific numerical targets due to uncertainty surrounding historical
abundance levels. So, the plan suggested an interim goal of doubling
the population sizes within 20 years, which corresponds to an annual
growth rate of about 3.5 percent. Because historical size of humpback
whale populations continues to be uncertain (Bettridge et al., 2015)
two decades after the recovery plan was finalized, and humpback whale
survey periods have not spanned 20 years since issuance of the 1991
recovery plan, data are not available to evaluate the status of
humpback whale populations against these goals. Therefore, the BRT
focused its biological risk analysis primarily on recent abundance
trends and whether absolute abundance was sufficient for biological
viability in light of consideration of the factors under Section
4(a)(1). This is a valid approach that we often use to evaluate the
risk of extinction to populations.
The BRT also ranked the severity of 16 current or imminent threats
to the humpback whale DPSs (1 = low or none, threat is likely to have
no or minor impact on population size or the growth rate; 2 = medium,
threat is likely to moderately reduce the population size or the growth
rate of the population; 3 = high, threat is likely to seriously reduce
the population size or the growth rate of the population, 4 = very
high, threat is likely to eliminate the DPS, unknown = severity of
threat is unknown) and also indicated whether the trend of any threat
was increasing.
Finally, the BRT members assessed the risk of extinction for each
DPS by distributing 100 likelihood points among 3 categories of
extinction risk: (1) High Risk = a species or DPS has productivity,
spatial structure, genetic diversity, and/or a level of abundance that
place(s) its persistence in question. The demographics of a species/DPS
at such a high level of risk may be highly uncertain and strongly
influenced by stochastic and/or small population effects. Similarly, a
species/DPS may be at high risk of extinction if it faces clear and
present threats (e.g., imminent destruction, modification, or
curtailment of its habitat; or disease epidemic) that are likely to
create an imminent risk of extinction; (2) Moderate Risk = a species or
DPS is at moderate risk of extinction if it exhibits characteristics
indicating that it is likely to be at a high risk of extinction in the
future. A species/DPS may be at moderate risk of extinction due to
projected threats and/or declining trends in abundance, productivity,
spatial structure, or diversity; and (3) Not at Risk = a species or DPS
is not at risk of extinction.
The BRT decided to evaluate risk of extinction over a time frame of
approximately 60 years, which corresponds to about three humpback whale
generations. The BRT concluded it could be reasonably confident in
evaluating extinction risk over this time period (the foreseeable
future) because current trends in both the biological status of the
species and the threats it faces are reasonably foreseeable over this
period of time. In making our listing determinations, we have applied
this same time horizon. In the next sections, we summarize the
information presented in the BRT's status review report; see Bettridge
et al. (2015) for more details.
Abundance and Trends for Each DPS
West Indies DPS
As discussed above, this DPS consists of the humpback whales whose
breeding range includes the West Indies and whose feeding range
primarily includes the Gulf of Maine, eastern Canada, and western
Greenland. While many West Indies whales also use feeding grounds in
the central (Iceland) and eastern (Norway) North Atlantic, many whales
from these feeding areas appear to winter in another location. The
breeding range of this DPS within the West Indies is the entire
Antillean arc, from Cuba to the Gulf of Paria, Venezuela.
Several abundance estimates for the West Indies DPS have been made
from photo-identification studies and biopsy samples and genetic
identification using a Chapman 2-sample estimator, some comparing
feeding ground samples to West Indies breeding ground samples, others
comparing breeding ground samples to breeding ground samples
(Palsb[oslash]ll et al., 1997; Smith et al., 1999; Clapham, 2003;
Clapham et al., 2003a; Stevick et al., 2003; Barlow et al., 2011;
Waring et al., 2012). Those estimates using breeding-to-breeding ground
comparisons tend to be negatively biased (Barlow et al., 2011). The
most accurate estimate made using photo-identification studies for the
Years of the North Atlantic Humpback (YONAH) data (1992 and 1993 data)
was 10,752 (CV = 6.8 percent) (Stevick et al., 2003). A Chapman 2-
sample estimator was also applied to the genetic identification data,
again using the feeding grounds (Gulf of Maine, Canada, and Greenland)
as the mark, and the West Indies breeding ground as the recapture. This
resulted in an estimate of 10,400 (95 percent CI 8,000-13,600; Smith et
al., 1999). Note that this is nearly identical to the photo-based
estimate using an identical estimator (10,752 photo vs. 10,400
genetic).
Additional sampling was conducted in the West Indies in 2004 and
2005 in order to obtain an updated abundance estimate for the West
Indies population (More of North Atlantic Humpbacks (MONAH) project;
(Clapham, 2003; Waring et al., 2012), and the BRT reviewed a
preliminary analysis of these data. A Chapman 2-sample estimator was
applied to the MONAH genetic identification data, using the feeding
grounds (Gulf of Maine only) as the mark, and the West Indies breeding
ground as the recapture, resulting in an estimate of 12,312 (95 percent
CI 8,688-15,954) (NMFS unpublished data). This estimate is nearly
directly comparable to the genetic estimate of 10,400 for 1992-93
(Smith et al., 1999), with the exception that the earlier YONAH
estimate used marked animals from Canada and West Greenland in addition
to the Gulf of Maine. If it can be assumed that whales from Canada and
Greenland have the same capture probability in the West Indies as do
whales from the Gulf of Maine, this should not introduce any bias. The
MONAH estimate of 12,312 is consistent with the increasing trend for
the West
[[Page 22318]]
Indies shown in Stevick et al. (2003), though it suggests the
increasing trend in the population has slowed down.
Stevick et al. (2003) estimated the average rate of increase for
the West Indies breeding population at 3.1 percent per year (SE = 0.5
percent) for the period 1979-1993, but because of concerns that the
same data may have been used twice and potentially lead to an over-
estimate of the precision of the trend estimate, they re-calculated the
trend analysis using only one set of abundance estimates for each time
period. The revised trend for this time period was still 3.1 percent
(SE=1.2 percent). When the MONAH estimate of 12,312 was added to the
analysis, the increase from 1979-80 to 2004-05 was estimated to be 2.0
percent (SE=0.6 percent) per year, lower than for the earlier time
period, but the increase was still significantly different from 0.0 (p
= 0.008). The Silver Bank population, which serves as a proxy for the
West Indies DPS, may be increasing or may be leveling off, but there
are not enough data yet to support a strong conclusion.
In contrast, estimates from feeding areas in the North Atlantic
indicate strongly increasing trends in Iceland (1979-88 and 1987-2007),
Greenland (1984-2007), and the Gulf of Maine (1979-1991). There is some
indication that the increase rate in the Gulf of Maine has slowed in
more recent years (6.5 percent from 1979 to 1991 (Barlow and Clapham
(1997)), 0-4 percent from 1992-2000 (Clapham et al. (2003a))). It is
not clear why the trends appear so different between the feeding and
breeding grounds. A possible explanation would be that the Silver Bank
breeding ground has reached carrying capacity, and that an increasing
number and percentage of whales are using other parts of the West
Indies as breeding areas. If local abundance has indeed increased in
some areas other than Silver Bank, it would suggest that the West
Indies population is larger than estimated by the MONAH study, and that
the increase rate of the overall population may be higher than the 2
percent we estimate.
Cape Verde Islands/Northwest Africa DPS
The population abundance and population trend for the Cape Verde
Islands/NW Africa DPS are unknown. The Cape Verde Islands photo-
identification catalog contains only 88 individuals from a 20-year
period (1990-2009) (Wenzel et al., 2010). Of those 88 individuals, 20
(22.7 percent) were seen more than once, 15 were seen in 2 years, 4
were seen in 3 years, and 1 was seen in 4 years. The relative high re-
sighting rate suggests a small population size with high fidelity to
this breeding area, although the DPS may also contain other, as yet
unknown, breeding areas (Wenzel et al., 2010).
Western North Pacific DPS
The abundance of humpback whales in the Western North Pacific is
estimated to be around 1,000, based on the photo-identification,
capture-recapture analyses from the years 2004-2006 by the ``Structure
of Populations, Levels of Abundance and Status of Humpback Whales in
the North Pacific'' (SPLASH) program (Calambokidis et al., 2008) from
two primary sampling regions, Okinawa and Ogasawara. The growth rate of
the Western North Pacific DPS is estimated to be 6.9 percent
(Calambokidis et al., 2008) between 1991-93 and 2004-06, although this
could be biased upwards by the comparison of earlier estimates based on
photo-identification records from Ogasawara and Okinawa with current
estimates based on the more extensive records collected in Ogasawara,
Okinawa, and the Philippines during the SPLASH program. However, the
overall number of whales identified in the Philippines was small
relative to both Okinawa and Ogasawara, so any bias may not be large.
Overall recovery seems to be slower than in the Central and Eastern
North Pacific. Humpback whales in the Western North Pacific remain rare
in some parts of their former range, such as the coastal waters of
Korea, and have shown no signs of a recovery in those locations (Gregr,
2000; Gregr et al., 2000).
Hawaii DPS
Calambokidis et al. (2008) estimated the size of the humpback whale
populations frequenting the Hawaii breeding area at 10,000 individuals,
and assuming that proportions from the Barlow et al. (2011) estimate of
21,808 individuals in breeding areas in the North Pacific are likely to
be similar to those estimated by Calambokidis et al. (2008), the
population size frequenting the Hawaii breeding area would have
increased to about 12,000 individuals. The most recent growth rate for
this DPS was estimated between 5.5 percent and 6.0 percent
(Calambokidis et al., 2008).
Mexico DPS
A preliminary estimate of abundance of the Mexico DPS is 6,000-
7,000 from the SPLASH project (Calambokidis et al., 2008), or higher
(Barlow et al., 2011). There are no estimates of precision associated
with that estimate, so there is considerable uncertainty about the
actual population size. However, the BRT was confident that the
population is likely to be much greater than 2,000 in total size.
Estimates of population growth trends do not exist for the Mexico DPS
by itself. Given evidence of population growth throughout most of the
primary feeding areas of the Mexico DPS (California/Oregon
(Calambokidis et al., 2008), Gulf of Alaska from the Shumagins to
Kodiak (Zerbini et al., 2006a)), it was considered unlikely this DPS
was declining, but the BRT noted that a reliable, quantitative estimate
of the population growth rate for this DPS is not currently available.
Central America DPS
Individual humpback whales in the Central America DPS migrate from
breeding grounds off Costa Rica, Panama, Guatemala, El Salvador,
Honduras, and Nicaragua to feeding grounds off California, Oregon, and
Washington. A preliminary estimate of abundance of the Central America
population is ~500 from the SPLASH project (Calambokidis et al., 2008),
or ~600 based on the reanalysis by Barlow et al. (2011). There are no
estimates of precision associated with these estimates, so there is
considerable uncertainty about the actual population size. Therefore,
the actual population size could be somewhat larger or smaller than
500-600, but the BRT considered it very unlikely to be as large as
2,000 or more. The size of this DPS is relatively low compared to most
other North Pacific breeding populations (Calambokidis et al., 2008).
The trend of the Central America DPS was considered unknown.
Brazil DPS
The most recent abundance estimate for the Brazil DPS comes from
aerial surveys conducted off the coast of Brazil in 2002-2005 (Andriolo
et al., 2010). These surveys covered the continental shelf between
6[deg] S. and 24[deg]30' S. and provided a best estimate of 6,400
whales (95 percent CI = 5,000-8,000) in 2005. This estimate corresponds
to nearly 24 percent of this DPS' pre-exploitation abundance (Zerbini
et al., 2006d). Nearly 80 percent of the whales are found in the
Abrolhos Bank, the eastern tip of the Brazilian continental shelf
located between 16[deg] S. and 18[deg] S. (Andriolo et al., 2010). The
best estimate of population growth rate is 7.4 percent per year (95
percent CI = 0.5-14.7 percent) for the period 1995-1998 (Ward et al.,
2011).
Gabon/Southwest Africa DPS
The lower and upper bounds of the abundance estimate for Iguela,
Gabon,
[[Page 22319]]
are 6,560 (CV=0.15) for 2001-2004 and 8,064 (CV=0.12) for 2001-2005.
These were generated using mark-recapture genetic data, and numerous
other (generally similar) estimates are available depending on model
assumptions (Collins et al., 2008). There are no trends available for
this DPS, and it is not entirely clear how the estimates relate to
potential subdivision within the DPS (Collins et al., 2008). Using a
Bayesian estimation methodology, Johnston and Butterworth (2008)
estimate the Gabon population to be in the range of 65-90 percent of
its pre-exploitation size.
Southeast Africa/Madagascar DPS
The most recent abundance estimates for the Madagascar population
were from surveys of Antongil Bay, 2000-2006 (Cerchio et al., 2009).
Estimates using data from 2004-2006 and involving ``closed'' models of
photo-identification of individuals and genotype data were 7,406 (CV =
0.37, CI: 2106-12706) and 6,951 (CV = 0.33, CI: 2509-11394),
respectively. Additional estimates were made using various data sets
(e.g., photo-identification and genotype) and models, estimating 4,936
(CV = 0.44, CI: 2137-11692) and 8,169 individuals (CV = 0.44, CI 3476-
19497, Cerchio et al., 2009). The mark-recapture data were derived from
surveys over several years and thus may represent the abundance of
whales breeding off Madagascar, in addition to possibly whales breeding
in Mayotte and the Comoros (Ersts et al., 2006), and to a smaller
degree from the East African Mainland (Razafindrakoto et al., 2008).
Earlier estimates exist, including one of 2,532 (CV = 0.27)
individuals (Best et al., 1996) based on surveys of the continental
shelf region across the south and southeast coasts of Madagascar in
1994. However, these surveys likely did not cover the full distribution
of humpback whales in the area. Data from a 1991 survey yielded an
estimate of 1,954 whales (CV = 0.38) (Findlay et al., 1994). A
subsequent line transect survey in 2003 included a larger region of the
coast (Findlay et al., 2011). From these, two estimates were generated
in 2003: 6,664 whales (CV = 0.16); and 5,965 (CV = 0.17) when data were
stratified by coastal regions.
Two trends in relative abundance have been calculated from land-
based observations of the migratory stream passing Cape Vidal, east
South Africa in July 1998-2002, and July 1990-2000. The first was an
estimate of 12.3 percent per year (Findlay and Best, 2006) (however,
this estimate is likely outside biological plausibility for this
species (Bannister and Hedley, 2001; Noad et al., 2008; Zerbini et al.,
2010)); and the second is 9.0 percent (an estimate that is within the
range calculated for other Southern Hemisphere breeding grounds (e.g.,
Ward et al., 2006; Noad et al., 2008; Hedley et al., 2009)). Both rates
are considered with caution because the surveys were short in duration.
It is not certain that these estimates represent the growth rate of the
entire DPS. Given this uncertainty, and the uncertainty from the short
duration of the surveys, it is likely the DPS is increasing, but it is
not possible to provide a quantitative estimate of the rate of increase
for the entire DPS.
West Australia DPS
Abundance of northbound humpback whales in the southeastern Indian
Ocean in 2008 was estimated at 21,750 (95 percent CI = 17,550-43,000)
based upon line transect survey data (Hedley et al., 2009). The current
abundance appears likely close to the historical abundance for the DPS,
although there is some uncertainty of the historical abundance because
of difficulties in allocating catch to specific breeding populations
(IWC, 2007a). The current abundance is large relative to any of the
general guidelines for viable abundance levels (see earlier
discussion). The rate of population growth is estimated to be ~10
percent annually since 1982, which is at or near the estimated
physiological limit of the species (Bannister, 1994; Bannister and
Hedley, 2001) and well above the interim recovery goal.
East Australia DPS
Abundance of the East Australia DPS was estimated to be 6,300-7,800
(95 percent CI: 4,040-10,739) in 2005 based on photo-ID data (Paton and
Clapham, 2006; Paton et al., 2008; Paton et al., 2009). The annual rate
of increase is estimated to be 10.9 percent for humpback whales in the
southwestern Pacific Ocean (Noad et al., 2008). This estimate of
population increase is very close to the biologically plausible upper
limit of reproduction for humpbacks (Zerbini et al., 2010). The surveys
presented by Noad et al. (2005; 2008) have remained consistent over
time, with a strong correlation (r > 0.99) between counts and years.
Oceania DPS
The Oceania humpback whale DPS is of moderate size (3,827 whales in
New Caledonia, Tonga, French Polynesia and Cook Islands combined;
CV=0.12) (South Pacific Whale Research Consortium et al., 2006);
however, no trend information is available for this DPS. The DPS is
quite subdivided, and the population estimate applies to an aggregate
(although it is known that sub-populations differ in growth rates and
other demographic parameters). There are some areas of historical range
extent that have not rebounded and other areas without historical
whaling information (Fleming and Jackson, 2011). There is uncertainty
regarding which geographic portion of the Antarctic this DPS uses for
feeding. The complex population structure of humpback whales within the
Oceania region creates higher uncertainty regarding demographic
parameters and threat levels than for any other DPS.
Southeastern Pacific DPS
Individuals of the Southeastern Pacific population migrate from
breeding grounds between Costa Rica and northern Peru to feeding
grounds in the Magellan Straits and along the Western Antarctic
Peninsula. Though no quantitative growth rate information is available
for this DPS, abundance estimates over a 13-year period suggest that
the DPS size is increasing, and abundance was estimated to be 6,504 (95
percent CI: 4270-9907) individuals in 2005-2006 (F[eacute]lix et al.,
2006a; F[eacute]lix et al., 2011). Total abundance is likely to be
larger because only a portion of the DPS was enumerated.
Arabian Sea DPS
Mark-recapture studies using tail fluke photographs collected in
Oman from 2000-2004 yielded a population estimate of 82 individuals (95
percent CI: 60-111). However, sample sizes were small, and there are
various sources of possible negative bias, including insufficient
spatial and temporal coverage of the population's suspected range
(Minton et al., 2010b).
Reproductive rates in this DPS are not well understood. Cow-calf
pairs were very rarely observed in surveys off the coast of Oman,
composing only 7 percent of encounters in Dhofar, and not encountered
at all since 2001. Soviet whaling catches off Oman, Pakistan and
northwestern India also included low numbers of lactating females (3.5
percent of mature females) relative to pregnant females (46 percent of
mature females) (Mikhalev, 1997).
No trend data are available for this DPS. A low proportion of
immature whales (12.4 percent of all females) was also found, even
though catches were indiscriminate with respect to sex and condition
(Mikhalev, 1997), suggesting that either calf mortality in this DPS is
high, immature animals occupy areas that have not been surveyed, or
that the whales have reproductive `boom and bust' cycles which respond
to high annual variation in productivity. The
[[Page 22320]]
BRT noted that the entire region has not been surveyed; however, in
areas where the whales are likely to be, not many whales have been
observed. The BRT noted that this is a very small population but felt
that there was some uncertainty in abundance estimates.
Summary of Abundance and Trends
The BRT summarized abundance and trend information for all humpback
whale DPSs (Tables 7 and 8 in Bettridge et al., 2015).
In the North Atlantic Ocean, the abundance of the West Indies DPS
is much greater than 2,000 individuals and is increasing moderately.
However, little is known about the total size of the Cape Verde
Islands/Northwest Africa DPS, and its trend is unknown.
In the Pacific Ocean, the abundance of the Okinawa/Philippines DPS
(as identified by the BRT) is thought to be about 1,000 individuals
with unknown trend. Little is known about the abundance of humpback
whales from the unknown breeding ground (identified as the Second West
Pacific DPS by the BRT), but it is likely to number at least 100 or
more, with unknown trend. Combining this information, we conclude that
there are at least 1,100 individuals in the Western North Pacific DPS,
and the trend is unknown. The abundances of the Hawaii and Mexico DPSs
are known to be much greater than 2,000 individuals and are thought to
be increasing moderately. The abundance of the Central America DPS is
thought to be about 500 individuals with unknown trend.
In the Southern Hemisphere, all seven DPSs are thought to be
greater than 2,000 individuals in population size. The Brazil DPS is
increasing either rapidly or moderately. The trend in the Gabon/
Southwest Africa DPS is unknown, while the Southeast Africa/Madagascar
DPS is thought to be increasing. The West Australia and East Australia
DPSs are both large and increasing rapidly. The Southeastern Pacific
DPS is thought to be increasing. And the trend of the Oceania DPS is
unknown.
The estimated abundance of the Arabian Sea DPS is less than 100,
but its entire range was not surveyed, so it could be somewhat larger.
Its trend is unknown.
Summary of Section 4(a)(1) Factors Affecting the 14 Humpback Whale DPSs
Section 4 of the ESA (16 U.S.C. 1533) and implementing regulations
at 50 CFR part 424 set forth procedures for adding species to the
Federal List of Endangered and Threatened Species. Under section
4(a)(1) of the ESA, the Services must determine if a species is
threatened or endangered because of any of the following five factors:
(A) The present or threatened destruction, modification, or curtailment
of its habitat or range; (B) overutilization for commercial,
recreational, scientific, or educational purposes; (C) disease or
predation; (D) the inadequacy of existing regulatory mechanisms; or (E)
other natural or manmade factors affecting its continued existence.
In this rulemaking, information regarding the status of each of the
14 humpback whale DPSs is considered in relation to these factors. The
information presented here is a summary of the information in the
Status Review Report (Bettridge et al., 2015). The reader is directed
to the Threats Analysis subsection under each DPS in the Status Review
Report for a more detailed discussion of the factors and how they
affect each DPS.
Section 4(a)(1) Factors Applicable to All DPSs
A. The Present or Threatened Destruction, Modification, or Curtailment
of its Habitat or Range
The BRT discussed habitat-related threats to humpback whale
populations, including coastal development, contaminants, energy
exploration and development, and harmful algal blooms (HABs).
Substantial coastal development is occurring in many regions, and may
include construction that can cause increased turbidity of coastal
waters, higher volume of ship traffic, and physical disruption of the
marine environment. Noise associated with construction (e.g., pile
driving, blasting, or explosives) and dredging has the potential to
affect whales by generating sound levels believed to disturb marine
mammals under certain conditions. The majority of the sound energy
associated with both pile driving and dredging is in the low frequency
range (<1,000 Hz) (Illingworth and Rodkin Inc., 2001; Reyff, 2003;
Illingworth and Rodkin Inc., 2007). Because humpback whales would only
be affected when close to shore, the BRT believed that these effects on
the whales would generally be low. However, if coastal development
occurred in seasonal areas or migration routes where whales
concentrate, individuals in the area could be more seriously affected.
Scheduling in-water construction activities to avoid those times when
whales may be present would likely minimize the disturbance. The BRT
was unaware of any circumstance of coastal development resulting in
humpback whale serious injury or mortality and therefore determined
that in general coastal development likely poses a low level threat to
humpback whales.
For purposes of the status review, the BRT agreed to consider as
contaminants heavy metals, persistent organic pollutants, effluent,
airborne contaminants, plastics, and other marine debris and pollution,
with the exception of oil spills, which is evaluated under ``energy
exploration and development.'' Numerous regions were highlighted as
having known or hypothesized high contaminant levels from run-off,
large human populations, and low levels of regulatory control.
Halogenated organic pollutants (including dichloro-diphenyl-
trichloroethane (DDT)), hexachlorocyclohexane (HCH) and chlordane (CH)
insecticides, polychlorinated biphenyl (PCB) coolants and lubricants,
and polybrominated diphenyl ether (PBDE--flame retardants) can persist
in the environment for long periods. Air-borne pollutants are
particularly concentrated in areas of industrialization, and in some
high latitude regions (Aguilar et al., 2002). While the use of many
pollutants is now either banned or strictly regulated in some countries
(e.g., DDTs and PCBs), their use is still unregulated in many parts of
world, and they can be transported long distances via oceanographic
processes and atmospheric dispersal (Aguilar et al., 2002).
Humpback whales can accumulate lipophilic compounds (e.g.,
halogenated hydrocarbons) and pesticides (e.g., DDT) in their blubber,
as a result of feeding on contaminated prey (bioaccumulation) or
inhalation in areas of high contaminant concentrations (e.g., regions
of atmospheric deposition) (Barrie et al., 1992; Wania and Mackay,
1993). Some contaminants (e.g., DDT) are passed on maternally to young
during gestation and lactation (e.g., fin whales, Aguilar and Borrell,
1994). Elfes et al. (2010) described the range and degree of organic
contaminants accumulated in the blubber of humpback whales sampled on
Northern Hemisphere feeding grounds. Concentrations were high in some
areas (Southern California and Northern Gulf of Maine), possibly
reflecting proximity to industrialized areas in the former case, and
prey choice in the latter (Elfes et al., 2010). There were also higher
levels of PCBs, PBDEs, and CH insecticides in the North Atlantic Ocean
(Gulf of Maine and Bay of Fundy) than in the North Pacific (California,
Southeast Alaska, Aleutian Islands). The highest levels of DDT were
found in whales feeding off Southern
[[Page 22321]]
California, a highly urbanized region of the coast with substantial
discharges (Elfes et al., 2010). This same study found a linear
increase in PCB, DDT, and chlordane concentration with age of the
whales sampled. Generally, concentrations of these contaminants in
humpback whales were low relative to levels found in odontocetes
(O'Shea and Brownell, 1994). Little information on levels of
contamination is available from humpback whales on Southern Hemisphere
feeding grounds.
The health effects of different doses of contaminants are currently
unknown for humpback whales (Krahn et al., 2004c). There is evidence of
detrimental health effects from these compounds in other mammals,
including disease susceptibility, neurotoxicity, and reproductive and
immune system impairment (Reijnders, 1986; DeSwart et al., 1996;
Eriksson et al., 1998). Contaminant levels have been proposed as a
causative factor in lower reproductive rates found among humpback
whales off Southern California (Steiger and Calambokidis, 2000), but at
present the threshold level for negative effects, and transfer rates to
calves, are unknown for humpback whales. Metcalfe et al. (2004) found
in biopsy-sampled humpback whale young-of-the-year in the Gulf of St.
Lawrence PCB levels similar to that of their mothers and other adult
females, indicating that bioaccumulation can be rapid, and that
transplacental and lactational partitioning did little to reduce
contaminant loads.
Although there has been substantial research on the identification
and quantification of such contaminants on individual whales, no
detectable effect from contaminants has been identified in baleen
whales. There may be chronic, sub-lethal impacts that are currently
unknown. The difficulty in identifying contaminants as a causative
agent in humpback whale mortality and/or decreased fecundity led the
BRT to conclude the severity of this threat was low in all regions,
except where lack of data indicated a finding of unknown.
The BRT defined identified threats from energy exploration and
development to include oil spills from pipelines, rigs, or ships,
increased shipping, and construction surrounding energy development
(oil, gas, or alternative energy). This category does not include noise
from energy development, which is considered under ``anthropogenic
noise.'' Little is known about the effects of oil or petroleum on
cetaceans and especially on mysticetes (baleen whales, characterized by
having baleen plates for filtering food from water, rather than teeth
like in the toothed whales (odontocetes)). Oil spills that occur while
whales are present could result in skin contact with the oil, baleen
fouling, ingestion of oil, respiratory distress from hydrocarbon
vapors, contaminated food sources, and displacement from feeding areas
(Geraci et al., 1989). Actual impacts would depend on the extent and
duration of contact, and the characteristics of the oil. Most likely,
the effects of oil would be irritation to the respiratory membranes and
absorption of hydrocarbons into the bloodstream (Geraci et al., 1989).
Polycyclic aromatic hydrocarbons (PAHs) are components of crude oil
which are not easily degraded and are insoluble in water, making them
quite detrimental in the marine environment (Pomilla et al., 2004).
PAHs have been associated with proliferative lesions and alteration to
the immune and reproductive systems (Martineau et al., 2002). Long-term
ingestion of pollutants, including oil residues, could affect
reproduction, but data are lacking to determine how oil may fit into
this scheme for humpback whales.
Although the risk posed by operational oil rigs is likely low,
failures and catastrophic events that may result from the presence of
rigs pose high risks. Since the BRT had already determined that threat
assessments would focus on present threats, the mere presence of oil
rigs was not interpreted to warrant a threat level above low. However,
the level of impact that such a catastrophic event may have on a
population was considered in the evaluations.
Some algal blooms are harmful to marine organisms and have been
linked to pollution from untreated industrial and domestic wastewater.
Toxins produced by different algae can be concentrated as they move up
the food chain, particularly during algal blooms. Naturally occurring
toxin poisoning can be the cause of whale mortalities and is
particularly implicated when unusual mortality events (UME) occur.
Despite these UMEs, the BRT determined that HABs represent a minor
threat to most humpback whale populations. HABs may be increasing in
Alaska, but the BRT was unaware of records of humpback whale mortality
resulting from HABs in this region.
B. Overutilization for Commercial, Recreational, Scientific or
Educational Purposes
The BRT described whaling (commercial, scientific, subsistence
hunting, and other ``hunts''), whale-watching, and scientific research
activities and evaluated whether they were impacting humpback whales.
Direct hunting, although rare today, was the main cause of initial
depletion of humpback whales and other large whales. The BRT believed
that the likelihood that commercial whaling will resume in the
foreseeable future is currently low (see discussion under Inadequacy of
Regulatory Mechanisms below). With regard to scientific whaling, Japan
has already announced its plan to remove humpback whales from its
scientific proposals in the future (Government of Japan, 2014).
In summary, the current impact of all whaling activities on global
humpback whale populations is very low, with only a handful of humpback
whales taken annually in two known aboriginal harvests. The BRT
discussed the possibility of expanded commercial whaling of humpback
whales in the Southern Ocean but determined that new whaling action in
the foreseeable future was unlikely. Therefore, the BRT attributed a
low level risk of whaling for all but one DPS (see Western North
Pacific DPS section).
Whale-watch tourism is a global industry with major economic value
for many coastal communities (O'Connor et al., 2009). The industry has
been expanding rapidly since the 1980s (estimated 3.7 percent global
increase in whale watchers per year between 1998-2008, O'Connor et al.,
2009; Kessler and Harcourt, 2012). Whale-watching operations have been
documented in 119 countries worldwide as of 2008, including on many
humpback whale feeding grounds, breeding grounds, and migratory
corridors (O'Connor et al., 2009). Efforts to manage whale-watching
operations have included limiting the number of whale-watching vessels,
limiting the time vessels spend near whales, specifying the manner of
operating around whales, and establishing limits to the period of
exposure of the whales. In some areas, whale-watching industries
operate under regulations while others operate under guidelines or are
still unregulated, and this industry is still growing rapidly in many
areas (over 10 percent per year in Oceania, Asia, South America,
Central America and the Caribbean) (Carlson, 2009; O'Connor et al.,
2009).
Weinrich et al. (2008) observed that the most common reported
response of humpback whales to whale-watching boats was increased
swimming speed during exposure; there was little evidence of
significant effects on inter-breath intervals and blow rates. Passive
acoustic monitoring and localization of humpback whale songs in the
presence of whale-watching boats on Brazilian
[[Page 22322]]
breeding grounds also found that whales moved away from the boat in the
majority of cases (68.4 percent of the time when boats were less than
2.5 miles (4.0 km) distant, Sousa-Lima and Clark, 2009).
Only one study has attempted to assess the population-level effects
of whale-watching on humpback whales, as the relevant parameters are
very difficult to measure. Weinrich and Corbelli (2009) reported that
calving rate and calf survival to age 2 in humpback whales on
Stellwagen Bank (part of the Gulf of Maine feeding ground) did not seem
to be negatively affected by whale-watching. The authors noted,
however, that in areas of heavy ship traffic, isolating the impacts of
whale-watching on biological parameters is difficult and may not be
conclusive (Weinrich and Corbelli, 2009) and is difficult to determine
at either the individual or population level.
The BRT discussed the available evidence regarding the impact of
whale-watching on humpback whale populations. All available evidence
supports the conclusion that the impact of these activities on humpback
whale populations is negligible, and the BRT determined this threat is
low for all DPSs.
Humpback whales have been the subject of field research studies for
decades. The primary objective of many of these studies has generally
been to gather data for behavioral and ecological studies. In the
United States, permits authorize investigators to make close approaches
to endangered whales for photographic identification, biopsy sample
collection, behavioral observations, passive acoustic recording, aerial
photogrammetry, satellite tagging, and underwater observations.
Research on humpback whales is likely to continue and increase in the
future, especially for the collection of genetic information,
photographic studies, and acoustic studies. Research activities could
result in disturbance to humpback whales, but they are closely
monitored and evaluated in the United States in an attempt to minimize
any necessary impacts of research. Regulation of research activities in
other nations varies from effectively no regulation to regulations
comparable to those in the United States. The BRT discussed the
available evidence regarding the impact of scientific research on
humpback whale populations. All available evidence supports the
conclusion that the impact of these activities is negligible, and the
BRT determined this threat is low for all DPSs.
C. Disease or Predation
Information on disease or parasites is unavailable for many
humpback whale populations. Direct monitoring of species biochemistry
and pathology, used to determine the state of health in humans and
domestic animals, is very limited for humpback whales, and there is
little published on humpback whale disease as a result. Humpback whales
carry a crustacean ectoparasite (the cyamid Cyamus boopis). While the
whale is the main source of nutrition for this parasite (Schell et al.,
2000), there is little evidence that the parasite contributes to whale
mortality. Humpback whales can also carry the giant nematode
Crassicauda boopis (Bayliss, 1920), which is known to cause a serious
inflammatory response (leading to vascular occlusion and kidney
failure) in a few balaenopterid species (Lambertsen, 1992).
Individual humpback whales in Hawaiian waters have a high
occurrence of skin lesions, but it is unclear whether this is due to a
parasite or disease. It is estimated that approximately 60 percent of
adults in Hawaii and Oceania have these skin lesions. Whether the
lesions are entirely benign is unknown. The BRT concluded that where
some information is available, disease and parasites do not pose a
substantial threat to humpback whale populations.
The most common predator of humpback whales is the killer whale
(Orcinus orca, Jefferson et al., 1991), though predation by large
sharks may also occur. Attacks by false killer whales (Pseudorca
crassidens) have also been reported or inferred on rare occasions.
Attacks by killer whales on humpback whale calves has been inferred by
the presence of distinctive parallel `rake' marks from killer whale
teeth across the flukes (Shevchenko, 1975). While killer whale attacks
of humpback whales are rarely observed in the field (Ford and Reeves,
2008), the proportion of photo-identified whales bearing rake scars is
between zero and 40 percent, with the greater proportion of whales
showing mild scarring (1-3 rake marks) (Wade et al., 2007; Steiger et
al., 2008). This suggests that attacks by killer whales on humpback
whales vary in frequency across regions. It also suggests that either
most killer whale attacks result in mild scarring, or those resulting
in severe scarring (4 or more rakes, parts of fluke missing) are more
often fatal. Most observations of humpback whales under attack from
killer whales reported vigorous defensive behavior and tight grouping
when more than one humpback whale was present (Ford and Reeves, 2008).
Photo-identification data indicate that rake marks are usually
acquired in the first year of life, although attacks on adults also
occur (Wade et al., 2007; Steiger et al., 2008). Killer whale predation
may influence survival during the first year of life (Wade et al.,
2007). There has been some debate as to whether killer whale predation
(especially on calves) is a motivating factor for the migratory
behavior of humpback whales (Corkeron and Connor, 1999; Clapham, 2001).
How significantly motivating this factor is also depends on the
importance of humpback whales in the diet of killer whales, another
debated topic that remains inconclusive (Springer et al., 2003; Wade et
al., 2007; Kuker and Barrett-Lennard, 2010). No analyses of killer
whale stomach contents have revealed remains of humpback whales
(Shevchenko, 1975), suggesting that if humpback whales are taken at
all, they comprise at most a small part of the diet. However, these
analyses took place during the height of the whaling period, when
humpback whales were at a low density and may therefore have been less
available for predation.
There is also evidence of shark predation on calves and entangled
whales (Mazzuca et al., 1998). Shark bite marks on stranded whales may
often represent post-mortem feeding rather than predation, i.e.,
scavenging on carcasses (Long and Jones, 1996).
The threat of predation was ranked as low or unknown for all DPSs
because the level of mortality is unknown, but it is likely not
prohibiting population growth.
D. Inadequacy of Existing Regulatory Mechanisms
Numerous international and regional regulatory mechanisms are in
place to protect humpback whales directly or indirectly.
The International Whaling Commission (IWC) was set up under the
International Convention for the Regulation of Whaling (ICRW), signed
in 1946. The IWC established an international moratorium on commercial
whaling for all large whale species in 1982, effective in 1986; this
affected all member (signatory) nations (paragraph 10e, IWC, 2009a).
The IWC has set the catch limits for commercial whaling at zero since
1985. Since that time, the IWC's Scientific Committee has developed a
stock assessment and catch limit methodology called the ``revised
management procedure,'' with the goal of providing information on catch
limits consistent with maintaining sustainable populations. As of 2014,
the IWC has maintained the zero catch
[[Page 22323]]
limit, and this policy has engendered considerable debate within the
organization. The IWC's regulations provide a process by which
countries may object to specific provisions, and Norway and Iceland
currently allow commercial whaling based on these objections.
Iceland and Norway currently hunt a number of whale species
commercially under objection to the IWC moratorium, although humpback
whales have not been hunted by either nation in recent years. The
present international moratorium on commercial whaling will remain in
place unless a 75 percent majority of IWC signatory members votes to
lift the moratorium. If this were to happen, then, under current IWC
management procedures, humpback whale stocks considered to have
recovered to over 54 percent of their pre-whaling levels (based on a
detailed ``comprehensive assessment'' of their population status) could
be subject to commercial whaling, with a quota that in theory would be
determined by the Revised Management Procedure. This procedure
implements a quasi-Bayesian Catch Limit Algorithm to calculate
allowable catches for each stock (Cooke, 1992). The effects of these
catches on population abundance would be simulated via a series of
Implementation Simulation Trials prior to agreement of quotas for
commercial hunting. Since whaling is carried out under objection by
Iceland and Norway, they are not subject to this management scheme for
allocating quotas for any species.
The United States first incorporated the IWC's regime into domestic
law in the 1971 Pelly Amendment to the Fisherman's Protective Act of
1967. This amendment provides that when the Secretary of Commerce
determines that the nationals of a foreign country are diminishing the
effectiveness of an international fishery conservation program
(including the IWC's program), the Secretary shall certify this fact to
the President. The President then has the discretion to ban importation
of fishing products from the offending country. The United States has
threatened sanctions under the Pelly Amendment on a number of
occasions, but to date, it has not imposed economic sanctions on marine
products. In November 1974, pressure from the United States contributed
to Japan and the Soviet Union complying with the 1974-1975 quotas.
Norway was certified in 1987 and several times thereafter. Japan has
been certified three times, the last being in 2000, and Iceland has
been certified several times, including in 2011 for whaling activities.
These measures were further strengthened by the 1979 Packwood-
Magnuson Amendment to the Fishery Conservation and Management Act of
1976. It provides that, when the Secretary of Commerce certifies that a
country is diminishing the effectiveness of the work of the IWC, the
Secretary of State must reduce that country's fishing allocation in
U.S. waters by at least 50 percent. Certification under the Packwood-
Magnuson Amendment also serves as certification under the Pelly
Amendment. The threatened application in 1980 of the Packwood-Magnuson
and Pelly Amendments led South Korea to agree to follow IWC guidelines
restricting the use of cold (i.e., non-explosive) harpoons. Faced with
similar pressure, the Republic of China (Taiwan) placed a complete ban
on whaling in 1981. Without United States support, it is possible that
the 1986 moratorium would have been substantially limited, as nations
such as Iceland, Japan, Norway, and the Soviet Union would have opted
out and continued commercial whaling.
Since implementation of the international moratorium on whaling,
some nations have continued to hunt whales under Article VIII of the
ICRW, which allows the killing of whales for scientific research
purposes. Three nations originally conducted scientific whaling:
Iceland, Norway, and Japan. Presently only Japan pursues scientific
whaling, under the programs JARPAII and JARPNII (`Japanese Whale
Research Program under Special Permit in the Antarctic' and `North
Pacific,' respectively). Scientific whaling is presently unregulated,
and no catch limits are enforced for this activity (Clapham et al.,
2003b). In 2012, the Government of Japan issued Special Permits
authorizing the implementation of a catch limit of Antarctic minke,
fin, and humpback whales for scientific purposes in the Southern Ocean;
a research catch limit of up to 50 humpback whales was included in the
Special Permits. To date, however, no humpback whales have been taken
for scientific research by any country. On March 31, 2014, after the
2013/14 Japanese whale hunt season in the Antarctic, the International
Court of Justice ruled that past Japanese whaling programs were
illegal, and Japan immediately terminated its JARPAII programs. In
September 2014, Japan agreed to a new requirement to submit new
research proposals to the IWC 6 months before the next annual IWC
Scientific Committee meeting (in May 2015) so that the IWC could assess
whether lethal samples are necessary for a specific research program
and whether the number of whales sampled is scientifically justified.
Because of the timing, Japan will not hunt whales in the Southern Ocean
during the 2014/15 season, and this will be the first time in 30 years
that Japan has not hunted for whales in the Antarctic. Japan's proposed
research plan for new scientific whale research programs in the
Antarctic Ocean (NEWREP-A, http://iwc.int/sc-documents) was released on
November 19, 2014, and it includes only a small number of minke whales.
The IWC also develops catch limits for aboriginal whaling,
including take of humpback whales in coastal areas of Greenland and the
West Indies. The ICRW allows for signatory nations to harvest whales
for scientific purposes through their own national permit process,
although humpback whales have not been reported to have been taken
under this process. The current commercial whaling moratorium is
providing significant protection to humpback whales.
The Convention on International Trade in Endangered Species of Wild
Fauna and Flora (CITES) is aimed at protecting species at risk from
unregulated international trade. CITES regulates international trade in
animals and plants by listing species in one of its three appendices.
The level of monitoring and control to which an animal or plant species
is subject depends on the appendix in which the species is listed.
Appendix I includes species threatened with extinction which are or may
be affected by trade; trade of Appendix I species is only allowed in
exceptional circumstances. Appendix II includes species not necessarily
threatened with extinction presently, but for which trade must be
regulated in order to avoid utilization incompatible with their
survival. Appendix III includes species that are subject to regulation
in at least one country, and for which that country has asked other
CITES Party countries for assistance in controlling and monitoring
international trade in that species. Humpback whales are currently
listed in Appendix I under CITES. With the IWC commercial whaling
moratorium in place since 1985, commercial trade has not been a problem
for humpback whales. However, if the moratorium should ever be lifted
in the future, the humpback whale's CITES Appendix I listing would
restrict trade so that it would not contribute to the extinction risk
of the species. Given this support and the long history of CITES work
and resolutions to support the IWC whaling moratorium, we do not expect
the
[[Page 22324]]
CITES status of the humpback whale to change if ESA protections are
removed from the species or any DPSs of the species. For example, CITES
Resolution Conf. 11.4 (Rev. CoP12) welcomed the Resolution passed by
the IWC at its Special Meeting in December 1978 requesting that the
Conference of the Parties to the Convention, at its second meeting,
take all possible measures to support the IWC ban on commercial whaling
for certain species and stocks of whales.
The International Maritime Organization (IMO), a United Nations
agency and the recognized international authority on shipping and
safety at sea, participates in reducing the shipping industry's impacts
to the sea from pollution (oil, garbage, noxious substances).
Regulations to address pollution from maritime vessels include MARPOL
(International Convention for the Protection of Pollution from Ships),
MARPOL Annexes, International Conventions on Oil Pollution Preparedness
Response and Co-operation, and Prevention of Marine Pollution by
Dumping of Wastes and Other Matter. The IMO's Marine Environment
Protection Committee designates regions as ``Particularly Sensitive Sea
Areas'' (PSSA) and ``Areas to be Avoided'' for various ecological,
economic, or scientific reasons. PSSA regions include The Great Barrier
Reef (Australia), the Gal[aacute]pagos Islands (Ecuador), and the
Papahanaumokuakea Marine National Monument (North Pacific).
The IMO was approached for the first time regarding conservation of
an endangered whale species in 1998--a protective measure for North
Atlantic right whales (Silber et al., 2012). Since then, the IMO has
been approached over a dozen times with nations' proposals to establish
or amend routing measures in various locations to reduce the threat of
vessel collisions with endangered whales, including humpback whales
(Silber et al., 2012). For example, the IMO has endorsed Areas To Be
Avoided in U.S. and Canadian waters to reduce the threat of ship
strikes of right whales (Fleming and Jackson, 2011, pp. 28-29),
measures that also benefit humpback whales. IMO-endorsed modifications
to Traffic Separation Schemes (TSS) have been established in areas off
Boston, San Francisco, and near Santa Barbara (the latter two primarily
for humpback whales); and a new TSS, along with vessel speed
advisories, has been proposed for the Pacific side of the Panama Canal
to protect large whale species from vessel collisions.
Humpback whales are protected by the MMPA (16 U.S.C. 1361 et seq.).
The West Indies, Western North Pacific, Hawaii, Mexico, and Central
America DPSs of the humpback whale can be found in U.S. waters and are
protected under the MMPA when in U.S. waters as well as from takings by
U.S. vessels or persons on the high seas. The MMPA includes a general
moratorium on the taking and importing of marine mammals, which is
subject to a number of exceptions. Some of these exceptions include
take for scientific purposes, public display, subsistence use by Alaska
Natives, and unintentional incidental take coincident with conducting
lawful activities.
U.S. citizens who engage in a specified activity other than
commercial fishing (which is specifically and separately addressed
under the MMPA) within a specified geographical region may petition the
Secretaries to authorize the incidental, but not intentional, taking of
small numbers of marine mammals within that region for a period of not
more than 5 consecutive years (16 U.S.C. 1371(a)(5)(A)). The Secretary
``shall allow'' the incidental taking if the Secretary finds that ``the
total of such taking during each five-year (or less) period concerned
will have a negligible impact on such species or stock and will not
have an unmitigable adverse impact on the availability of such species
or stock for taking for subsistence uses.'' If the Secretary makes the
required findings, the Secretary also prescribes regulations that
specify: (1) Permissible methods of taking, (2) means of effecting the
least practicable adverse impact on the species, their habitat, and
their availability for subsistence uses, and (3) requirements for
monitoring and reporting.
Similar to promulgation of incidental take regulations, the MMPA
also established an expedited process by which U.S. citizens can apply
for an authorization to incidentally take small numbers of marine
mammals where the take will be limited to harassment (16 U.S.C.
1371(a)(5)(D)). These authorizations are limited to 1 year, and, as
with incidental take regulations, the Secretary must find that the
total of such taking during the period will have a negligible impact on
such species or stock and will not have an unmitigable adverse impact
on the availability of such species or stock for taking for subsistence
uses. NMFS refers to these authorizations as Incidental Harassment
Authorizations.
Under the MMPA, NMFS also evaluates and provides permits for the
taking of large whale species for those engaged in scientific research
focused on those species. NMFS has also issued rules under the
authority of the MMPA and the ESA to promulgate regulations to address
the threat of vessel collisions with large whale species, and these
regulations would remain in place even if humpback whales are no longer
listed under the ESA.
The MMPA provides additional protections to ``depleted'' marine
mammals. For example, NMFS may not provide a take waiver for depleted
stocks (section 101(a)(3)(A)), authorize importation of individual
animals taken from depleted marine mammal stocks except pursuant to a
permit for scientific research or for enhancing the survival or
recovery of a species or stock (section 102(b)(3)(B)), or issue
research permits involving the lethal taking of a marine mammal from a
species or stock that is depleted (unless the Secretary determines that
the results of such research will directly benefit that species or
stock, or that such research fulfills a critically important research
need)(section 104(c)(3)(B)). In addition, if a stock is depleted, it is
automatically considered ``strategic,'' which then has other management
implications. For example, under Section 112(e) of the MMPA, if the
Secretary determines that impacts on rookeries, mating grounds, or
other areas of similar ecological significance to marine mammals may be
causing the decline or impeding the recovery of a strategic stock, the
Secretary may develop and implement conservation or management measures
to alleviate those impacts. Also, under Section 118, the Secretary may
develop and implement a take reduction plan designed to assist in the
recovery or prevent the depletion of each strategic stock that
interacts with a commercial fishery.
The humpback whale is considered ``depleted'' under the MMPA
because of its endangered status under the ESA. See Effects of this
Rulemaking below for a discussion of the potential consequences of
removing ESA protections from the humpback whale. While MMPA
``depleted'' status provides additional protections to humpback whales,
the MMPA provides substantial protections to humpback whales in U.S.
waters and from takings by U.S. persons and vessels on the high seas,
whether they are depleted or not.
The ESA requires Federal agencies to conduct their activities in
such a way as to conserve species listed as threatened or endangered.
Section 7 of the ESA also requires Federal agencies, in consultation
with the FWS and/or NMFS, to ensure that activities they authorize,
fund or carry out are not likely to jeopardize the continued existence
of any listed species (or species proposed for listing) or result in
[[Page 22325]]
the destruction or adverse modification of designated or proposed
critical habitat of such species. We have conducted scores of Section 7
consultations with the United States Coast Guard (USCG), the Army Corps
of Engineers, the Bureau of Ocean Energy Management, and other agencies
to ensure actions by these agencies do not adversely affect listed
large whale species, including humpback whales. The ESA forbids the
import, export, or interstate or foreign sale of species listed as
endangered without a special permit. It also makes ``take'' of species
listed as endangered illegal--forbidding, among other things, the
killing, harming, harassing, pursuing, or removing the species from the
wild (16 U.S.C. 1532(19)). Any or all of these protections may be
provided to a species listed as threatened through regulations issued
under ESA section 4(d)(16 U.S.C. 1533(d)). Of course, ESA protections
for a species apply only if a species is listed as threatened or
endangered under the ESA.
Whale strike mitigation measures currently in place for some
vessels and regions include using dedicated observers (Weinrich and
Pekarik, 2007), speed reduction in some important habitat areas (73 FR
60173; October 10, 2008), and shifting of shipping lanes away from
areas of whale concentration to accommodate humpback whales and other
species. Passive acoustic monitoring in areas of high shipping traffic
also has promise for notifying mariners of whales in the area, as this
method is relatively inexpensive, although detection is limited to
vocalizing whales and specific source locations can be hard to
determine (Silber et al., 2009).
TSSs are in place for San Francisco Bay and the Santa Barbara
Channel to ensure safety of navigation. These TSSs were amended in June
1, 2013, to lessen the possibility of fatal vessel collisions with
humpback whales and other listed large whale species. Modifications
include narrowing and extending the Northern and Western approaches
while the inbound lane of the Santa Barbara Channel TSS has been
shifted shoreward to reduce the co-occurrence of ships and whales and
reduce the likelihood of a vessel/whale collision. We expect these TSSs
and modifications to help reduce the likelihood of vessel collisions
with humpback whales.
Congress enacted the Coastal Zone Management Act (CZMA) in 1972
when it realized that rapid growth was threatening the vital productive
coastal areas of the country. Congress determined that the most
effective management of coastal resources would be achieved if states
were given a major role in developing and administering management
programs. The Act sought to assure the states that their management
programs would not be disregarded by Federal agencies whose activities
would affect the coastal zone. For example, the stepped-up Outer
Continental Shelf (OCS) development policies of the early 1970s led to
the 1976 amendments that assured greater state involvement in the
planning stages of oil and gas development.
The CZMA accomplishes its goal primarily by encouraging the states
to develop voluntary coastal zone management programs. Once a state has
an approved program, it becomes eligible for Federal funds and acquires
the benefit of the ``consistency provisions.'' Sections 307(c) and
307(d) of the CZMA establish classes of Federal activities that must be
consistent with state programs. These include Federal activities that
directly affect the coastal zone, development projects, Federal
licenses and permits, OCS exploration, development, and production
plans, and Federal assistance to states and local governments. Every
coastal state in the United States except for Alaska currently has an
approved coastal zone management program. Consistency determinations
under the CZMA help to ensure that OCS projects do not adversely impact
humpback whales or humpback whale habitat.
The U.S. Park Service has jurisdiction over marine waters (through
the Fish and Wildlife Coordination Act) in Glacier Bay National Park
and Preserve (established 1980; modified 1985). The following
regulations are in place to protect humpback whales occurring there in
the summer: Restrictions on the number of vessels entering park waters;
restrictions on vessel operating conditions in the known presence of
humpback whales, mandatory vessel operating requirements in certain
designated ``whale waters,'' mandatory vessel speed limits at certain
times and locations; mandatory boater education for boaters entering
the area, regulations restricting the harvest of humpback whale prey
species and ship board observers to quantify ship strikes and
interactions between cruise ships and whales. These regulations should
contribute somewhat to reducing the extinction risk of the Hawaii and
Mexico DPSs of the humpback whale because some of these individuals
feed in the park.
Under the National Marine Sanctuaries Act, NOAA has broad
discretion to enact guidelines and regulations to provide protection to
a number of large whale species, including the humpback whale in key
aggregation locations. Humpback whales routinely occur in Stellwagen
Bank, Gulf of the Farrallones, Channel Islands, Monterey Bay, Cordell
Bank, and Olympic Coast National Marine Sanctuaries. The Hawaiian
Islands Humpback Whale National Marine Sanctuary (HIHWNMS) was
established primarily to provide protections to a key North Pacific
humpback whale breeding/nursery area, and therefore, it should
contribute to reducing the extinction risk of the Hawaii DPS of the
humpback whale. NOAA's Office of National Marine Sanctuaries recently
proposed to expand the boundaries and scope of the HIHWNMS, amend the
regulations for HIHWNMS, change the name of the sanctuary, and revise
the sanctuary's terms of designation and management plan (80 FR 16224;
March 26, 2015). The purpose of the proposed action is to transition
the HIHWNMS from a single-species management approach to an ecosystem-
based management approach. As part of these revisions, NOAA proposed to
revise the existing HIHWNMS humpback whale approach regulation at 15
CFR 922.184 to help minimize incidences of humpback whale harassment or
injury, to reduce adverse behavioral responses, and to limit vessel
strikes within the sanctuary (80 FR 16224; March 26, 2015, at 16227).
The Stellwagen Bank and Gulf of the Farallones National Marine
Sanctuaries, in particular, have active humpback whale research
programs and/or have established vessel speed advisories, whale
approach guidelines, and other measures to reduce human threats to
humpback and other large whale species. These two national marine
sanctuaries should contribute to reducing the extinction risk of the
West Indies, Mexico, and Central America DPSs, as they provide
protections to humpback whales in these DPSs when they are in their
feeding grounds.
Numerous nations have defined marine protected areas and
sanctuaries that provide some protection to humpback whales (Hoyt,
2011), and various nations have developed local regulations or
guidelines governing whale watching activities (O'Connor et al., 2009).
Hundreds of national laws also exist related directly or indirectly to
the conservation of marine mammals (Bettridge et al., 2015, Appendix
B). Where appropriate, some of these are discussed in more detail in
the DPS-specific sections.
[[Page 22326]]
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Competition with fisheries, aquaculture, anthropogenic sound,
vessel strikes, fishing gear entanglement, and climate change are all
factors that may negatively impact humpback whales.
The BRT discussed the issue of competition with fisheries at
length. In some areas, (e.g., Northern Gulf of Maine and Southeast
Alaska) fishermen encircle feeding humpback whales and harvest fish
from the bait balls upon which humpback whales feed (D. Matilla,
unpublished observation). However, there is no evidence that this
impacts the individuals or significantly depletes the food source. In a
review of the evidence for interspecific competition in baleen whales,
Clapham and Brownell (1996) found it to be extremely difficult to prove
that inter-specific competition comprises an important factor in the
population dynamics of large whales.
Aquaculture is not known to be a significant threat to humpback
whales. Some entanglements have been recorded off Australia. Colombia
has substantial aquaculture activity in inshore areas, but there is no
information regarding the impact of this activity on humpback whales.
The BRT determined that for most DPSs, aquaculture does not pose a
significant threat to humpback whales and should be assigned a low
threat level. Sufficient information was not available to determine the
threat level to the Western North Pacific and Arabian Sea DPSs.
Humans introduce sound intentionally and unintentionally into the
marine environment for navigation, oil and gas exploration and
acquisition, research, and military activities, to name a few examples.
Noise exposure can result in a range of impacts, from those causing
little or no impact to those being potentially severe, depending on the
source, level, and various other factors. Response to noise varies by
many factors, including the type and characteristics of the sound
source, distance between the source and the receptor, characteristics
of the animal (e.g., hearing sensitivity, behavioral context, age, sex,
and previous experience with sound source) and time of day or season.
Noise may be intermittent or continuous, steady (non-impulsive) or
impulsive, and may be generated by stationary or moving sources. As one
of the potential stressors to marine mammal populations, noise may
seriously disrupt communication, navigational ability, and social
patterns. Humpback whales use sound to communicate, navigate, locate
prey, and sense their environment. Both anthropogenic and natural
sounds may cause interference with these functions.
Anthropogenic sound has increased in all oceans over the last 50
years and is thought to have doubled each decade in some areas of the
ocean over the last 30 or so years (Croll et al., 2001; Weilgart, 2007;
Hildebrand, 2009). High levels of ambient anthropogenic noise are known
to elicit behavioral, acoustic, and physiological responses from large
whales, though the specific nature of these responses remains largely
unknown (Nowacek et al., 2007). Low-frequency sound comprises a
significant portion of this increase and stems from a variety of
sources including that primarily from shipping, and an increasing
amount from oil and gas exploration in some areas, as well as research
and naval activities. Understanding the specific impacts of these
sounds on mysticetes is difficult. However, it is clear that the
geographic scope of potential impacts is vast as low-frequency sounds
can travel great distances under water, but these sounds have the
potential to reduce communication space (e.g., shipping was predicted
to reduce communication space of singing humpback whales in the
northeast by 8 percent; Clark et al., 2009).
Humpback whales do not appear to be often involved in strandings
related to noise events. There is one record of two whales found dead
with extensive damage to the temporal bones near the site of a 5,000 kg
explosion which likely produced shock waves that were responsible for
the injuries (Ketten et al., 1993; Weilgart, 2007). Other detrimental
effects of anthropogenic noise include masking and possible temporary
threshold shifts. Masking results from noise interfering with cetacean
social communication, which may range greatly in intensity and
frequency. Some adjustment in acoustic behavior is thought to occur in
response to masking and humpback songs were found to lengthen during
LFA sonar activities (Miller et al., 2000). This altered song length
persisted 2 hours after the sonar activities stopped (Fristrup et al.,
2003). Researchers have also observed diminished song vocalizations in
humpback whales during remote sensing experiments 200 km away from the
whales' location in the Stellwagen Banks National Marine Sanctuary
(Risch et al., 2012). Hearing loss can also possibly be permanent if
the sound is intense enough but there is great variability across
individuals and other factors making it difficult to determine a
standardized threshold.
Excessive noise exposure may be damaging during early individual
development, may cause stress hormone fluctuations, and/or may cause
whales to leave an area or change their behavior within it (Weilgart,
2007). Some responses are subtle and may occur after the exposure.
Humpback whales exposed to underwater explosions and drilling
associated with construction activities did not appear to change their
behavior in reaction to the surveys but did appear to have reduced
orientation abilities. Higher rates of fatal entanglement in fishing
gear were observed in the area when whales were exposed to excessive
noise, although the cause for this elevated entanglement rate was
unclear (Ketten et al., 1993; Todd, 1996). Some studies have found
little reaction to noise and indicate potential tolerances to
anthropogenic sound over short time and small spatial scales (Croll et
al., 2001).
There is likely an important distinction between immediate
individual reactions to noise and long-term effects of noise exposure
to populations. The cumulative and synergistic effects may be more
harmful than studies to date have been able to assess. Though some
researchers have argued that habituation to sound may occur, this can
easily be confused with hearing loss or individual differences in
tolerance levels (Bejder et al., 2006). Scientifically recommended
mammal sound exposure levels have been determined and vary depending on
the sound source strength and the species of marine mammal(s) present
(Southall et al., 2007). NMFS has recently updated guidance for
temporary threshold shifts and permanent threshold shifts (see: http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm).
The issue of anthropogenic noise has been an area of intensive
research but population-level impacts on cetaceans have not been
confirmed. There is little definite information regarding, for example,
the interruption of breeding and other behaviors or a resulting
reduction in population growth or mortality of individuals. Therefore,
the BRT considered this to be a low threat for all DPSs.
Collisions between vessels and whales, or ship strikes, often
result in life-threatening trauma or death for the cetacean. Impact is
often caused by forceful contact with the bow or propeller of the
vessel. Ship strikes of humpback whales are typically identified by
evidence of massive blunt trauma (fractures of heavy bones and/or
hemorrhaging) in stranded whales,
[[Page 22327]]
propeller wounds (deep slashes or cuts) and fluke/fin amputations on
stranded or live whales (e.g., Wiley and Asmutis, 1995).
Laist et al. (2001), Jensen and Silber (2003), Vanderlaan and
Taggart (2007), and VanWaerebeek and Leaper (2008) compiled information
available worldwide regarding documented collisions between ships and
large whales (baleen whales and sperm whales). Humpback whales were the
second-most commonly reported victims of vessel strikes (following fin
whales). Of 292 recorded strikes contained in the Jensen and Silber
(2003) database, 44 were of humpback whales. As of 2008, there were
more than 143 recorded ship strikes involving humpback whales worldwide
(Van Waerebeek and Leaper, 2008); however, the reported number is
likely not a full representation of the actual number (particularly in
the Southern Hemisphere) as many likely go undetected or unreported
(Williams et al., 2011). Reporting of ship strikes is highly variable
internationally, with reports required from vessels in the domestic
waters of Australia, the United States, and New Zealand but not in
other countries. Based on the observations of vessel strike injuries
and mortalities, and whale strike mitigation measures described above
under Inadequacy of Existing Regulatory Mechanisms, the BRT considers
the threat of vessel collisions to be low to moderate, depending on
region, and generally increasing.
Humpback whales may break through, carry away, or become entangled
in fishing gear. Whales carrying gear may die at a later time, become
debilitated or seriously injured, or have normal functions impaired,
but with no assurance of the incident having been recorded. Of the
nations reporting to the IWC between 2003-2008, 64.7 percent (n=11)
noted humpback whale by-catch in their waters (Mattila and Rowles,
2010). Whales have been documented carrying gear by fishery observer
programs, opportunistic reports, and stranding networks. Some countries
(e.g., United States, Canada, Australia, South Africa) have well-
developed reporting and response networks that facilitate the
collection of information on entanglement frequency and impacts.
However, such programs do not guarantee that entanglements are
detected; fewer than 10 percent of humpback whale entanglements
involving Gulf of Maine humpback whales are reported, despite a strong
outreach and response network (Robbins and Mattila, 2004). Furthermore,
opportunistic reports that are not screened by experts do not
necessarily yield accurate information about events, including gear
type, configuration, and original site of entanglement (Robbins et al.,
2007b). The likelihood of receiving reports likely varies world-wide
due to differences in observer awareness, reporting mechanisms, and
possible negative implications for reporting fishermen (Mattila and
Rowles, 2010).
A study of gear removed from a subset of whales off the U.S. East
Coast showed that 89 percent involved pots/traps or gillnet gear
(Johnson et al., 2005). However, a wide range of gear types were
represented and every part of the gear was found to be capable of
entanglement (Johnson et al., 2005). The authors concluded that any
line in the water column poses a potential risk of entanglement to
humpback whales. Known gear types removed from, or documented on,
entangled whales in Alaska between 1990 and 2013 indicated 32 percent
of entanglements were from pot gear, 30 percent from gill net, 24
percent from other net, and 14 percent from a combination of longline,
seine, mooring line and marine debris (Jensen et al. 2014). This is
further supported by the wide range of entangling gear reported in the
South Pacific (Neilson, 2006; Lyman, 2009), Newfoundland (Lien et al.,
1992), and member nations of the IWC (Mattila and Rowles, 2010).
More than half of the humpback whale entanglements examined off the
U.S. East Coast involved entanglements around the tail (Johnson et al.,
2005). The mouth and flippers are also known attachment sites, but
their frequency is more difficult to assess. Scar-based studies have
been developed to systematically study the frequency of non-lethal
entanglement involving the tail (Robbins and Mattila, 2001; Robbins and
Mattila, 2004). These techniques have been used in the Gulf of Maine
(e.g., Robbins and Mattila, 2001; Robbins and Mattila, 2004; Robbins et
al., 2009), Southeast Alaska (Neilson et al., 2009), and more broadly
across the North Pacific Ocean (Robbins et al., 2007a; Robbins, 2009).
All populations studied in this manner to date have detected
individuals with entanglement-related injuries. Annual research in the
Gulf of Maine since 1997 has shown that a high percentage of
individuals exhibit entanglement injuries and that new injuries are
acquired at an average annual rate of 12 percent (Robbins et al.,
2009). A 2-year study in Southeast Alaska confirmed frequencies of
entanglement injuries that were comparable to the Gulf of Maine
(Neilson et al., 2009). Research undertaken across the North Pacific as
part of the SPLASH project further suggests that entanglement is
pervasive, but that interaction rates may be highest among coastal
populations (Robbins et al., 2007a; Robbins, 2009).
Both eye-witness reports and scar-based studies suggest that
independent juveniles are significantly more likely to become entangled
than adults (Robbins, 2009). Calves exhibit a lower frequency of
entanglement, likely due to having less time in which to have
encountered gear (Neilson et al., 2009). Sex differences in
entanglement frequency have been observed in some locations and time
intervals (Robbins and Mattila, 2001; Neilson et al., 2009), but these
effects have not persisted in longer studies (Robbins and Mattila,
2004).
Entanglement may result in only minor injury, or potentially may
significantly affect individual health, reproduction, or survival. In
one study, females with entanglement injuries produced fewer calves
than females with no evidence of entanglement; such impacts on
reproduction are still under investigation (Robbins and Mattila, 2001).
Mark-recapture studies of the fate of entangled whales in the Gulf of
Maine suggest that juveniles are less likely than adults to survive
(Robbins et al., 2008). Observed entanglement deaths and serious
injuries in that region are known to exceed what is considered
sustainable for the population (Glass et al., 2009). Most deaths likely
go unobserved and preliminary studies suggest that entanglement may be
responsible for 3-4 percent of total mortality, especially among
juveniles (Robbins et al., 2009).
Much more is known about fishing gear entanglement in the Northern
Hemisphere than in the Southern Hemisphere. The BRT noted the
commercialization of bycatch off Japan, meaning an entangled whale is
legally allowed to be killed and sold on the market (Lukoschek et al.,
2009). Therefore, entanglement often leads to death for humpback whales
in this region. While the number of reported bycaught animals is not
large (3-5), the number of reports has been increasing and reports may
not reflect the actual number caught. The BRT also noted that the
Mexico population has one of the highest scar rates from nets and lines
in the North Pacific, indicating a high entanglement rate. Based on
this information, the BRT concluded that the severity of the threat of
fishing gear entanglements varies depending on region, ranging from low
to high.
Climate change has received considerable attention in recent years,
with growing concerns about global
[[Page 22328]]
warming and the recognition of natural climatic oscillations on varying
time scales, such as long-term shifts like the Pacific Decadal
Oscillation or short-term shifts, like El Ni[ntilde]o or La
Ni[ntilde]a. Evidence suggests that the biological productivity in the
North Pacific (Lowry et al., 1988; Quinn and Niebauer, 1995) and other
oceans could be affected by changes in the environment. Recent work has
found that copepod distribution has shown signs of shifting in the
North Atlantic due to climate change (Hays et al., 2005). Increases in
global temperatures are expected to have profound impacts on arctic and
sub-arctic ecosystems, and these impacts are projected to accelerate
during this century (ACIA, 2004; IPCC, 2007).
The IWC has held two workshops on the topic of climate change and
cetaceans (IWC, 1997; IWC, 2010a), and the reports of these meetings
provide useful summaries on the current state of knowledge on this
issue, and on the large uncertainties associated with any projections
of impact.
It is generally accepted that cetaceans are unlikely to suffer
problems because of changes in water temperature per se (IWC, 1997).
Rather, global warming is more likely to effect changes in habitats
that in turn potentially affect the abundance and distribution of prey
in these areas. Factors such as ocean currents and water temperature
may render currently used habitat areas unsuitable and influence
selection of migration, feeding, and breeding locations for humpback
and other whales. Changes in climate and oceanographic processes may
also lead to decreased productivity of, or lead to different patterns
in, prey distribution and availability. Such changes could affect
whales that are dependent on this prey. While these regional or ocean
basin-scale changes may occur, the actual magnitude and resulting
impacts are not known.
All cetacean species have undoubtedly lived through considerable
variation in climate (including multiple ice ages, and significant
warming events) over the course of their evolutionary history. However,
there is little knowledge regarding the ways in which cetaceans dealt
with climate change in the past. Examination of bones related to Basque
whaling in Canada indicate that the range of bowhead whales (Balaena
mysticetus) in the North Atlantic shifted south during the so-called
Little Ice Age in medieval times (McLeod et al., 2008). This almost
certainly reflected a shift in the distribution of prey because of
habitat and associated productivity changes, and it likely reflects the
ability of large whales to adapt and extend their range when necessary.
There are no data on similar historical shifts by humpback whales.
Considerable plasticity in the winter distribution of the species is
suggested by the fact that the use of Hawaii as a major breeding ground
appears to be a relatively recent phenomenon which occurred sometime in
the 20th century (Herman, 1979); the reason for such a shift is not
known, but it is important to recognize that the humpback's winter
distribution is not tied to prey resources or biological productivity,
a situation which presumably affords the species with flexibility in
its colonization of breeding habitats.
Climate change may disproportionately affect species with
specialized or restricted habitat requirements. The best-known example
of this involves dependence upon sea ice, which is thought to represent
a major problem for polar bears (Ursus maritimus), given that the
species primarily hunts pagophilic ringed seals (Phoca hispida)
(Schliebe et al., 2006). This represents a relatively simple and clear-
cut example of cause and effect in the climate change debate;
unfortunately, the situation for humpback whales and other cetaceans is
not nearly as simple, given the complexity of the ecosystems in which
they live. Climate change may exacerbate situations in which
populations are already small and/or significantly affected by other
anthropogenic impacts (such as entanglement or ship strikes). Species
which possess little ability to disperse or colonize new habitats will
also be particularly vulnerable.
None of these factors apply to humpback whales, with the possible
exception of the Arabian Sea population, which is thought to be small
and vulnerable to entanglement, shipping-related issues and possibly
pollution. Furthermore, the uniquely restricted range of this non-
migratory population is currently tied to seasonal monsoon-driven
biological productivity in a relatively small region; the impact of
climate change on this productivity is unknown, as is the ability of
these humpback whales to shift their range as may be needed.
As noted by IPCC (2007), species in general potentially respond in
one of three ways to major changes in climate: Redistribution,
adaptation, or extinction. Based upon what is known to date,
redistribution is the most likely response for most humpback whales.
Most large whales, including humpbacks, undertake extensive movements,
both during a feeding season and on migration. These broad ranges
(which routinely encompass much of an ocean basin), together with the
animals' ability to withstand prolonged periods of fasting through
utilization of fat reserves in their blubber, potentially provide the
whales with a means to adapt their ranges in response to major climate-
related spatial shifts in biological productivity, notably by seeking
out new habitats. This may in fact already be occurring in some places;
humpback whales have recently been observed in the eastern Chukchi and
Beaufort Seas (Clarke et al., 2013), north of their usual range; this
could represent the beginnings of a response to habitat changes
relating to diminishing sea ice in the Arctic, although it might also
simply reflect a growing population expanding its range. Prior to
extensive whaling, humpback whales appear to have been quite common in
at least the western (Russian) Chukchi Sea (Zenkovich, 1954; Tomilin,
1967), and are still observed there today (Clarke et al., 2013).
The BRT determined that the level of the threat of climate change
facing the Southern Hemisphere populations was slightly better
understood than that facing the Northern Hemisphere populations.
Warming waters are thought to be correlated with a decrease in krill
production in the Southern Ocean, and this threat is likely to
increase. The future negative impact implied by a low threat assignment
is dependent on a substantial decrease in krill populations, a
subsequent negative impact on prey resource availability to humpback
whales, and lack of suitable alternate prey such as fish.
The Southern Ocean is regarded as a relatively simple ecosystem,
but even here there are substantial problems in quantifying even the
most basic parameters such as prey abundance. Changes in this ecosystem
are also driven by cyclic variability on the scale of years to decades
(Murphy et al., 2007). Disentangling climate change effects from other
forms of variability including periodic physical forcing, requires time
series of data that are typically scarce or non-existent in the
Southern Ocean (Quetin et al., 2007). The responses of the Southern
Ocean ecosystem to climate change are likely to be complex. Sea ice
decreases may actually enhance overall primary production but could
reduce ice algae production which occurs at a critical time for krill
larvae (Arrigo and Thomas, 2004). On the other hand, the location of
upwelling of nutrient-rich deep water may change and result in enhanced
primary production in areas that are
[[Page 22329]]
otherwise unfavorable to krill (Prezelin et al., 2000).
The problems in assessing the relatively ``simple'' Southern Ocean
illustrate the huge problems involved in predicting future changes in
dynamic ecosystems, on scales that range from eddies and fronts to
entire ocean basins. Ecosystem models are crude at best. Full ecosystem
models involve innumerable parameters, yet data to quantify these--let
alone interactions among them--frequently do not exist.
The second IWC climate change workshop (IWC, 2010c) noted that data
sets for use in assessing impact and modeling the effects of climate
change must have: extensive duration (20-30 years or more of
information); good temporal resolution to capture variability on inter-
annual and longer scales; and sufficient spatial scale. Although long-
term studies of humpback whales exist in various locations in both
hemispheres, these are often compromised by issues such as sampling
bias, data gaps, and inconsistency of methods; furthermore, parallel
data of sufficient resolution on environmental variables are often
unavailable. The caveat above regarding the difficulty of disentangling
climate change effects from other variables applies equally to
determining the reasons for any observed changes in demographic
parameters of humpback whales.
It is instructive to compare the conclusions of the two IWC climate
change workshops, separated as they were by more than a decade. The
report of the 1996 workshop (IWC, 1997) notes that: ``. . . given the
uncertainties in modeling climate change at a suitable scale and thus
modeling effects on biological processes . . . at present it is not
possible to model in a predictive manner the effects of climate change
on cetacean populations.'' Thirteen years later, the second workshop
came to much the same conclusion (IWC, 2010c), finding that: ``. . .
improvements in climate models, as well as models that relate
environmental indices to whale demographics and distribution had [sic]
occurred. However, all models remain subject to considerable
uncertainty.''
The BRT assigned climate change a low threat level to all Southern
Hemisphere populations based on current impacts to the populations. The
threat posed by climate change to Northern Hemisphere humpback whale
populations is very uncertain, but the BRT thought it unlikely that
climate change was a major extinction risk factor. Melting and receding
ice sheets may open more feeding habitat for humpback whales in the
Northern Hemisphere. However, humpback whales in the Northern
Hemisphere do not feed primarily in Arctic waters (which are likely to
be the most significantly altered by climate change), and the extent to
which Arctic habitats may change to support aggregations of prey sought
by humpback whales is unknown.
Overall, it is clear that humpback whales worldwide have exhibited
considerable resilience despite a whaling history that removed the
great majority of animals from most populations. This resilience,
together with the species' flexibility in diet and apparent plasticity
in its distribution, provides some optimism that humpback whales can
adapt to significant environmental changes wrought by global warming.
Although we cannot predict how climate change may affect humpback
whales in the long term, at present most studied populations appear to
be recovering well, and it seems very unlikely that any population will
face extinction as a result of climate issues within the foreseeable
future. At this time, the record does not support a conclusion that
climate change is likely to influence extinction risk to humpback
whales in the foreseeable future.
West Indies DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Human population growth and associated coastal development
represent potential threats to this DPS in certain areas of the West
Indies, as well as in regions of high human population density in the
high-latitude feeding range. The major breeding habitats of Silver and
Navidad Banks are sufficiently remote from land that direct human
impact is for the most part unlikely. The largest concentration of
humpback whales in a West Indies habitat that is adjacent to the coast
occurs in Saman[aacute] Bay, Dominican Republic (Mattila et al., 1994).
There, tourism has spurred an increase in coastal development, which
has presumably introduced a rise in runoff and effluent discharge into
the waters of the bay. To date, there is no evidence of observable
impact on the humpback whales that visit the region, but no studies
have been conducted; that the whales do not feed in these tropical
waters likely decreases their risk from such point source pollution.
As noted above, although whales are found elsewhere in the West
Indies, densities outside Dominican Republic waters are relatively low.
Much of the additional habitat is in the waters of small islands in the
Leeward and Windward groups, where any coastal runoff is likely to be
effectively dispersed by highly dynamic water movements driven by
frequently strong trade winds.
In some feeding grounds, coastal runoff, vessel traffic and other
human activities represent a potential threat to humpback whales from
this DPS. This is likely to be most pronounced off the Mid-Atlantic and
northeastern United States, and least relevant in remote offshore areas
such as Greenland, Labrador and the Barents Sea. A study of
contaminants in humpback whales from the Gulf of Maine found elevated
levels of polychlorinated biphenyls (PCBs), polybrominated diphenyl
ethers (PBDEs), and chlordanes (Elfes et al., 2010), although the
authors concluded that these likely did not represent a conservation
concern.
Extensive oil and gas development and extraction occur in the
southern portion of the humpback whale's West Indies range, in the Gulf
of Paria off Venezuela, but nothing is known of the impacts of this on
the whales (Swartz et al., 2003). Energy exploration and development in
this area are expected to increase.
The best documented UME for humpback whales attributable to disease
occurred in 1987-1988 in the North Atlantic, when at least 14 mackerel-
feeding humpback whales died of saxitoxin poisoning (a neurotoxin
produced by some dinoglagellate and cyanobacteria species) in Cape Cod,
Massachusetts (Geraci et al., 1989). The whales subsequently stranded
or were recovered in the vicinity of Cape Cod Bay and Nantucket Sound,
and it is highly likely that other unrecorded mortalities occurred
during this event. Such events have been linked to increased coastal
runoff. During the first 6 months of 1990, seven dead juvenile (7.6 to
9.1 m long) humpback whales stranded between North Carolina and New
Jersey. The significance of these strandings is unknown.
Additional UMEs occurred in the Gulf of Maine in 2003 (12-15 dead
humpback whales on Georges Bank), 2005 (7 in New England), and 2006-7
(minimum of 21 whales), with no cause yet determined but HABs
potentially implicated (Gulland, 2006; Waring et al., 2009). In the
Gulf of Maine in 2003, a few sampled individuals among 16 humpback
whale carcasses were found with saxitoxin and domoic acid (produced by
certain species of diatoms, a different type of algae (Gulland, 2006)).
The BRT discussed the possible
[[Page 22330]]
levels of unobserved mortality that may be resulting from HABs and
determined that, as the West Indies population had been affected by
HABs in the past, it is likely experiencing a higher level of HAB-
related mortality than is detected.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Subsistence hunting in the North Atlantic occurs in Greenland and
the island of Bequia in St. Vincent and the Grenadines in the Lesser
Antilles (Reeves, 2002). Greenland began hunting humpback whales before
1780 (Reeves, 2002). As the take of bowhead whales decreased between
the years 1750 and 1850, humpback whales became a more frequent target
(Reeves, 2002). Beginning in 1986, the IWC has not granted any catch
limit for humpback whales to Denmark on behalf of Greenland, though
Greenland reported 14 infractions over the period 1988-2006. In 2010, a
catch limit was reinstated, and 27 humpbacks were killed between 2010
and 2012. In 1986, St. Vincent and the Grenadines, on behalf of the
native community of Bequia, asked for a humpback catch limit from the
IWC, based on its history of artisanal whaling in the community and the
small number of whales taken (Reeves, 2002). Bequia currently retains
an IWC ``block'' catch limit of up to 24 whales over a 6-year period
(2013-2018) (IWC, 2012); they took 4 whales in 2013. While this
subsistence hunting kills some West Indies DPS humpback whales in their
breeding and feeding grounds, it is not likely contributing
significantly to extinction risk of this DPS.
Humpback whales represent a major attraction for tourists in many
parts of the world, and in the West Indies their presence supports a
large seasonal whale-watching industry in Saman[aacute] Bay (Dominican
Republic). Although humpback whales can become remarkably habituated to
ecotourism-based vessel traffic, whale-watching excursions have the
potential to disturb or even injure animals. On feeding grounds such as
the Gulf of Maine, where a large whale-watching industry exists, the
extreme reaction of habitat displacement has not been observed; this
may partly be due to the existence of some guidelines for the operation
of whale-watching tours, as well as the fact that the whales are tied
to specific areas by a key resource (i.e., food). Since whales do not
eat while in sub-tropical waters in winter, they are theoretically far
less constrained in their choice of habitat; consequently, if the
whales are faced with high enough pressures from noise or other
disturbance, they might be able to leave one breeding area and move to
another.
It is not clear whether recent anecdotal reports linking a decline
in humpback whale abundance in Saman[aacute] Bay with increased cruise
ship traffic are valid, but the potential exists to drive whales out of
a breeding ground. The large number of whale-watching vessels and
increasing presence of cruise ships in Saman[aacute] Bay suggest that
it is very important to assess the effect of this traffic on the
behavior and habitat use of the whales there.
Currently, disturbance from whale watching is probably not a major
concern for Silver Bank. Although a small number of dive boats operate
``swim-with-whales'' tours there, their activities are regulated by the
Dominican Republic government, and are limited to a very small section
of the available habitat. There is currently no commercial or
recreational activity on Navidad Bank. With the exception of the Gulf
of Maine, there is minimal utilization of humpback whales for whale-
watching or ecotourism elsewhere in the North Atlantic.
This DPS is exposed to some scientific research activities in
waters off the United States, Canada, and West Indies, but at
relatively low levels. Adverse population effects from research
activities have not been identified, and overall impact is expected to
be low and stable.
It is unlikely that overutilization is contributing to the
extinction risk of the West Indies DPS.
C. Disease or Predation
There are no recent studies of disease in this population, but also
no indication that it is a major risk.
A study of apparent killer whale attacks in North Atlantic humpback
whales found scarring rates ranging from 8.1 percent in Norwegian
waters to 22.1 percent off western Greenland; scarring rates among
whales observed in the West Indies ranged from 12.3 percent to 15.3
percent (Wade et al., 2007). It is clear that most killer whale attacks
occur on first-year calves prior to arrival in high-latitudes (Wade et
al., 2007). However, this is not regarded as a serious threat to
population growth.
D. Inadequacy of Existing Regulatory Mechanisms
A moratorium on oil and gas exploration has been in place in the
Mid-Atlantic region since the early 1980s. In March 2010, President
Barack Obama announced plans to open the Mid-Atlantic and South
Atlantic planning areas to oil and gas exploration. The Federal
Government had scheduled a lease sale offshore of Virginia, to take
place in 2011. These lease sale plans were cancelled in May 2010
following the Deepwater Horizon oil spill in the Gulf of Mexico. In
December 2010, the Secretary of the Interior announced a ban on
drilling in Federal waters off the Atlantic coast through 2017. While
this ban remains in place, the Bureau of Ocean Energy Management is in
the process of issuing a final programmatic environmental impact
statement on possible geologic and geophysical activities along the
Atlantic Outer Continental Shelf (OCS) from Delaware to midway down
Florida's east coast. The PEIS considers the potential acoustic and
other impacts of these activities on marine mammals. These activities
will provide new data for the next 5-year OCS oil and gas program for
the South and Mid-Atlantic OCS and for possible oil and gas leasing in
the 2017-2022 period.
In Nova Scotia, oil and gas exploration and development began in
1967. Canadian government estimates show that Nova Scotia's oil and gas
resource potential is significant. In Nova Scotia, there are currently
two producing offshore natural gas projects, the Sable Offshore Energy
Project SOEP and Deep Panuke. In 1988, Canada implemented a moratorium
on oil and gas development on Georges Bank, to the southwest of Nova
Scotia. In 2010, Canada extended the moratorium, which was set to
expire at the end of 2012, until December 31, 2015.
Silver Bank, Navidad Bank, and portions of Saman[aacute] Bay have
been designated by the Dominican Republic as a humpback whale sanctuary
(Hoyt, 2013).
Whalers from the St. Vincent and the Grenadines island of Bequia
have a quota from the IWC; most recently, Bequia was given a ``block''
quota of up to 24 whales over a six-year period (2013-2018) (IWC,
2012). The Scientific Committee of the IWC has determined that the
allowed quota would have no impact on the growth rate of this
population (IWC, 2012).
As noted above, whale-watching activities in the Silver Bank are
regulated by the Dominican Republic government, and there is currently
no commercial or recreational activity on Navidad Bank.
Under the authority of the ESA and the MMPA, we have issued
regulations such as the NMFS right whale ship strike regulations in the
U.S. North Atlantic and other regional or local maritime speed zones,
and these help reduce the threat of vessel collisions involving
humpback whales. The ship
[[Page 22331]]
collision reduction rule established regulations to limit vessel speeds
to no more than 10 knots (18.5 km/hr), applicable to all vessels 65
feet (19.8m) or greater in length in certain locations and at certain
times of the year along the east coast of the U.S. Atlantic seaboard
(73 FR 60173; October 10, 2008).
In 1999, NMFS and the U.S. Coast Guard established two Mandatory
Ship Reporting systems aimed at reducing ship strikes of North Atlantic
right whales. When ships greater than 300 gross tons enter two key
right whale habitats--one off the northeast United States and one off
the southeast United States--they are required to report to a shore-
based station. In return, ships receive a message about whales, their
vulnerability to ship strikes, precautionary measures the ship can take
to avoid hitting a whale, and locations of recent sightings. While
these systems were designed to protect right whales specifically, they
are expected to also reduce the risk of ship strikes to other large
whales, including humpback whales (NMFS, 2008).
On February 18, 2005, the U.S. Coast Guard (USCG) announced a Port
Access Route Study (PARS) of Potential Vessel Routing Measures to
Reduce Vessel Strikes of North Atlantic Right Whales (70 FR 8312).
Potential vessel routing measures were analyzed and considered to
adjust existing vessel routing measures in the northern region of the
Atlantic Coast, which included Cape Cod Bay, the area off Race Point at
the northern end of Cape Cod, and the Great South Channel. As a result
of this information, we recommended realigning and amending the
location and size of the western portion of the TSS in the approach to
Boston, Massachusetts. The TSS was revised in 2007, and the new
configuration appeared on nautical charts soon thereafter.
On November 19, 2007, the USCG announced a second PARS to Analyze
Potential Vessel Routing Measures to Reduce Vessel Strikes of North
Atlantic Right Whales while also Minimizing Adverse Effects on Vessel
Operations (72 FR 64968). The study area included approaches to Boston,
MA, specifically, a northern right whale critical habitat in the area
east and south of Cape Cod, MA, and the Great South Channel, including
Georges Bank out to the exclusive economic zone boundary. In the second
PARS, the USCG recommended establishing a seasonal Area to be Avoided
(ATBA) and amending the southeastern portion of the TSS to make it
uniform throughout its length. On behalf of the United States, the USCG
submitted a series of proposals to the IMO (see International Maritime
Organization discussion above) to modify the TSS and to establish an
ATBA, which were subsequently endorsed by the IMO (Silber et al., 2012)
and as described in the IMO's publication, ``Ships' Routing'' 2008. In
2009, the TSS was revised and the ATBA was established. This was
followed by a notice in the Federal Register announcing these changes
(75 FR 77529; December 13, 2010) and NMFS added the changes to
applicable nautical charts. While the measures are designed
specifically for the North Atlantic right whale, they are expected to
benefit humpback whales co-occurring in these areas.
In 2007, a program of auto-detection buoys and real-time whale
vocalization detection information was incorporated into the Boston TSS
as mitigation for liquefied natural gas (LNG) ship strike risk,
primarily as a result of an ESA Section 7 consultation with the
Maritime Administration. This program, stipulated as a condition of the
consultation, was designed to reduce the threat of vessel collisions
with right whales and other listed large whale species, including
humpback whales in and around the boundaries of Stellwagen Bank
National Marine Sanctuary. When right whales are auto-detected in the
vicinity, LNG vessels are required to travel at speeds of 10 knots or
less, a measure that almost certainly reduces the likelihood of vessel
strikes of humpback whales occurring in the area as well.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
The largest potential threats to the West Indies DPS are
entanglement in fishing gear and ship strikes; these occur primarily in
the feeding grounds, with some documented in the mid-Atlantic U.S.
migratory grounds. There are no reliable estimates of entanglement or
ship-strike mortalities for most of the North Atlantic. During the
period 2003-2007, the minimum annual rate of human-caused mortality and
serious injury (from both entanglements and ship collisions) for the
Gulf of Maine feeding population averaged 4.4 animals per year (Waring
et al., 2009). Off Newfoundland, an average of 50 humpback whale
entanglements (range 26-66) was reported annually between 1979 and 1988
(Lien et al., 1988); another 84 were reported entangled in either
Newfoundland or Labrador from 2000-2006 (Waring et al., 2009). Not all
entanglements result in mortality (Waring et al., 2009). However, all
of these figures are likely to be underestimates, as not all
entanglements are observed. A study of entanglement-related scarring on
the caudal peduncle of 134 individual humpback whales in the Gulf of
Maine suggested that between 48 percent and 65 percent had experienced
entanglements (Robbins and Mattila, 2001).
Ship strike injuries were identified for 8 percent (10 of 123) of
dead stranded humpback whales between 1975-1996 along the U.S. east
coast, 25 percent (9 of 36) of which were along mid-Atlantic and
southeast states (south of the Gulf of Maine) between Delaware Bay and
Okracoke Island North Carolina (Wiley and Asmutis, 1995). Ship strikes
made up 4 percent of observed humpback whale mortalities between 2001-
2005 (Nelson et al., 2007) and 7 percent between 2005-2009 (Henry et
al., 2011) along the U.S. east coast, and the Canadian Maritimes. Among
strandings along the mid and southeast U.S. coastline during 1975-1996,
80 percent (8 of 10) of struck whales were considered to be less than 3
years old based on their length (Laist et al., 2001). This suggests
that young whales may be disproportionately affected. However, those
waters are thought to be used preferentially by young animals (Swingle
et al., 1993; Barco et al., 2002). It should be noted that ship strikes
do not always produce external injuries and may therefore be
underestimated among strandings that are not examined for internal
injuries.
Underwater noise can potentially affect whale behavior, although
impacts are unclear. Concerns about effects of noise include behavioral
disruption, interference with communication, displacement from habitats
and, in extreme cases, physical damage to hearing (Nowacek et al.,
2007). Singing humpback whales have been observed to lengthen their
songs in response to low-frequency active sonar (Miller et al., 2000)
and reduce song duration from distant remote sensing (Risch et al.,
2012). Hatch et al. (2008) conducted a study analyzing commercial
vessel traffic in the Stellwagen Bank National Marine Sanctuary and its
effect on ambient noise. This study revealed significantly elevated and
widespread ambient noise levels due to vessel traffic, but further
research is needed to determine the direct impacts to marine mammals.
Because of the low level of human activity on Silver and Navidad
Banks, noise is currently not a concern in this area. Saman[aacute]
Bay, however, already has much vessel activity and therefore has the
potential for considerable impact on whales from noise. Noise sources
include whale-watching vessels, which approach whales closely and thus
[[Page 22332]]
presumably create a loud acoustic environment in close proximity to the
animals, and cruise ships, which may be more distant but whose size
guarantees that, at certain frequencies, noise levels in the bay will
be very high. There are also additional sources in the form of
container ships or other commercial vessels that enter the bay
periodically. Underwater noise levels are expected to increase.
The BRT considered offshore aquaculture to be a low, but
increasing, threat to this DPS and competition with fisheries a low
threat to this DPS.
Overall population level effects from global climate change for
this DPS are not known; nonetheless, any potential impacts resulting
from this threat will almost certainly increase. Currently, climate
change does not appear to pose a significant threat to the growth of
this DPS now or in the foreseeable future.
HABs, vessel collisions, and fishing gear entanglements are likely
to moderately reduce the population size and/or the growth rate of the
West Indies DPS. All other threats, with the exception of climate
change (unknown severity), are considered likely to have no or minor
impact on population size or the growth rate of this DPS.
Cape Verde Islands/Northwest Africa DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Habitat conditions for this DPS are poorly known. Some members of
the population use the waters around the Cape Verde Islands for
breeding and calving, but where the remaining hypothesized fraction
goes is unknown. In considering the Cape Verde Islands/Northwest Africa
DPS, it was noted that oil spills occur off West Africa, but these
levels are thought to be lower than in some other regions and the
impact of non-catastrophic spills on humpback whales when they are on
the breeding grounds was not considered significant. The threat of
energy exploration to the Cape Verde Islands/Northwest Africa
population was considered low.
There is little to no information on the impacts of HABs on this
DPS.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Because the breeding range of this DPS is largely unknown, the
importance of anthropogenic disturbance (from activities such as whale-
watching, offshore aquaculture, fishing gear entanglements, and
scientific research) to this DPS is largely unknown. At present,
threats appear low relative to other populations, but again, much of
the distribution of individuals from the Cape Verde Islands/Northwest
Africa DPS is unknown. There is no current or planned commercial
whaling in this area.
C. Disease or Predation
There is little to no information on the impacts of disease,
predation, or parasites on this DPS.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the Cape Verde Islands/
Northwest Africa DPS were identified.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is little to no information on the impacts of vessel
collisions, climate change, or anthropogenic noise on the Cape Verde
Islands/Northwest Africa DPS, although each is expected to increase.
Competition with fisheries and offshore aquaculture were considered low
threats to this DPS.
The threats of HABs, disease, parasites, vessel collisions, fishing
gear entanglements, and climate change to this DPS are unknown. All
other threats to this DPS are considered likely to have no or minor
impact on the population size and/or growth rate.
Western North Pacific DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Humpback whales in the Western North Pacific are at some risk of
habitat loss or curtailment from a range of human activities.
Confidence in information about, and documentation of, these activities
is relatively good, except on the unknown breeding grounds included in
this DPS. Given continued human population growth and economic
development in most of the Asian region, these threats can be expected
to increase.
Coastal development, including shipping, and habitat degradation
are potential threats along most of the coast of Japan, South Korea and
China. Organochlorines and mercury are found in relatively high levels
in most cetaceans along the Asian coast (Simmonds, 2002). Although the
threat to the health of this DPS is unknown, the accumulation of these
pollutants can be expected to increase over time.
The BRT noted that the Sea of Okhotsk currently has a high level of
energy exploration and development, and these activities are likely to
expand with little regulation or oversight. The BRT determined that the
threat posed by energy exploration to the Okinawa/Philippines DPS it
identified is medium, but noted that there was low certainty regarding
this since specifics of feeding location (on or off the shelf) are
unavailable. If feeding activity occurs on the shelf in the Sea of
Okhotsk, energy exploration in this area could impact what is likely
one of the most depleted subunits of humpback whales. The threat posed
by energy exploration to the Second West Pacific DPS identified by the
BRT was unknown.
As above, naturally occurring biotoxins from dinoflagellates and
other organisms are known to exist within the range of this DPS,
although known humpback whale deaths attributable to biotoxin exposure
do not exist in the Pacific. The occurrence of HABs is expected to
increase with the growth of various types of human-related activities.
The level of confidence in the predicted increase is moderate.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
There are no proposals for scientific, aboriginal/subsistence or
commercial hunting of humpback whales in the North Pacific under
consideration by the IWC at this time. Some degree of illegal,
unreported or unregulated (IUU) exploitation, including `commercial
bycatch whaling,' has been documented in both Japan and South Korea
through genetic identification of whale meat sold in commercial markets
(Baker et al., 2000; Baker et al., 2006). Genetic monitoring of
Japanese markets (1993-2009) identified humpback whale as the source of
17 whale meat products. These are believed to have been killed through
direct or indirect fisheries entanglement (Steel et al., 2009). In
Japan and Korea, it is legal to kill and sell any entangled whale as
long as the take is reported; there is suspicion that this provides an
incentive for intentional ``entanglements,'' though the level of such
intentional takes is currently unknown (Lukoschek et al., 2009). Some
degree of IUU exploitation is also possible in other regions within the
range of humpback whales in the Western North Pacific DPS, including
Taiwan and the Philippines, given past histories of whaling. The full
extent of IUU exploitation is unknown. Official reports of whales taken
as bycatch entanglement and destined for commercial markets are
considered to be incomplete (Lukoschek et al., 2009). Some poaching is
reported to occur in Korean waters and is suspected off Japan (Baker et
al., 2002; IWC 2005c),
[[Page 22333]]
and for this reason the threat of whaling to the Western North Pacific
DPS was determined to be medium.
There is some whale-watching and non-lethal scientific research in
Japanese waters, primarily in Ogasawara and Okinawa, but this is at low
levels and not thought to pose a risk to this DPS.
C. Disease or Predation
The evidence of killer whale attacks on humpback whales in this DPS
is low (6-8 percent) relative to other North Pacific humpback whales
(Steiger et al., 2008). Certainty in this information is considered
moderate and the magnitude is expected to remain stable. There are no
reports of disease in this DPS and levels of parasitism are unknown.
Trends in the severity of disease and parasitism are also unknown.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the Western North Pacific DPS
were identified. A continuing source of potential adverse impacts to
humpback whales is interactions with vessels, including whale-watching
and fishing vessels. NMFS issued a final rule (66 FR 29502; May 31,
2001) effective in 2001 in waters within 200 nautical miles (370 km) of
Alaska, making it unlawful for a person subject to the jurisdiction of
the United States to (a) approach within 100 yards (91.4 m) of a
humpback whale, (b) cause a vessel or other object to approach within
100 yards (91.4 m) of a humpback whale or (c) disrupt the normal
behavior or prior activity of a whale. Exceptions to this rule include
approaches permitted by NMFS; vessels which otherwise would be
restricted in their ability to maneuver; commercial fishing vessels
legally engaged in fishery activities; and state, local and Federal
government vessels operating in official duty (50 CFR 224.103(b)). This
rule provides some protection from vessel strikes to a portion of
Western North Pacific DPS individuals while in their feeding grounds in
the Aleutian Islands, though the size and location of the area present
some challenge to enforcement. Its effectiveness could be improved
through greater general public awareness of the 100-yard (91.4-m)
regulation, particularly with regard to ``placing a vessel in path of
oncoming humpback . . .'' and ``operate at slow safe speed when near a
humpback whale.''
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Humpback whales in the Western North Pacific DPS are likely to be
exposed to relatively high levels of underwater noise resulting from
human activities that may include commercial and recreational vessel
traffic, and military activities. Overall population-level effects of
exposure to underwater noise are not well established, but exposure is
likely chronic and at relatively high levels. As vessel traffic and
other activities are expected to increase, the level of this threat is
expected to increase. The level of confidence in this information is
moderate.
The likely range of the Western North Pacific DPS includes some of
the world's largest centers of human activities and shipping. Although
reporting of ship strikes is requested in the Annual Progress reports
to the IWC, reporting by Japan and Korea is likely to be poor. A
reasonable assumption, although not established, is that shipping
traffic will increase as global commerce increases; thus, a reasonable
assumption is that the level of the threat will increase. The threat of
ship strikes was therefore considered to be medium for the Okinawa/
Philippines portion of this DPS and unknown for the Second West Pacific
portion of this DPS.
The BRT discussed the high level of fishing pressure in the region
occupied by the Okinawa/Philippines population (a small humpback whale
population). Although specific information on prey abundance and
competition between whales and fisheries is not known in this area,
overlap of whales and fisheries has been indicated by the bycatch of
humpback whales in set-nets in the area. The BRT determined that
competition with fisheries is a medium threat for this DPS, given the
high level of fishing and small humpback whale population.
The Fisheries Agency of Japan considers whales to be likely
competitors with some fisheries, although direct evidence of these
interactions is lacking for humpback whales in the region (other than
net entanglement). Whales along the coast of Japan and Korea are at
risk of entanglement related mortality in fisheries gear, although
overall rates of net and rope scarring are similar to other regions of
the North Pacific (Brownell et al., 2000). The threat of mortality from
any such entanglement is high, given the incentive for commercial sale
allowed under Japanese and Korean legislation (Lukoschek et al., 2009).
The reported number of humpback whale entanglements/deaths has
increased for Japan since 2001 as a result of improved reporting,
although the actual number of entanglements may be underrepresented in
both Japan and Korea (Baker et al., 2006). The level of confidence in
understanding the minimum magnitude of this threat is medium for the
Okinawa/Philippines portion of this DPS and low for the Second West
Pacific portion of this DPS, given the unknown wintering grounds and
primary migratory corridors.
Overall population level effects from global climate change are not
known; nonetheless, any potential impacts resulting from this threat
will almost certainly increase. The level of confidence in the
magnitude of this threat is poor.
In summary, energy development, whaling, competition with
fisheries, and vessel collisions are considered likely to moderately
reduce the population size or the growth rate of the Okinawa/
Philippines portion of the DPS, and fishing gear entanglements are
considered likely to seriously reduce its population size or growth
rate. Other threats are considered likely to have no or minor impact on
population size and/or the growth rate, or are unknown, for the Western
North Pacific DPS. In general, there is great uncertainty about the
threats facing the Second West Pacific portion of this DPS.
Hawaii DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Other than its Hawaiian Islands breeding area, the Hawaii DPS
inhabits some of the least populated areas in the United States
(Alaska) and Canadian (Northern British Columbia) coastal waters.
Coastal development, which may include such things as port expansion or
waterfront development, occurs in both the United States and Canada;
runoff from coastal development in Hawaii and continued human
population growth are potential threats. Confidence in information
about, and documentation of, these activities and their impacts is
moderate. Given continued human population growth in the region, the
threat can be expected to increase.
This DPS had the lowest levels of DDTs, PCBs, and PBPEs observed
for North Pacific humpback whales sampled on all their known feeding
grounds except Russia, between 2004 and 2006; in particular, levels
were lower than observed in humpback whales from the U.S. West Coast,
as well as the North Atlantic's Gulf of Maine (Elfes et al., 2010). The
levels observed in all areas are considered moderate and not expected
to have a significant effect on population growth (Elfes et al., 2010).
Confidence in this
[[Page 22334]]
information is moderate, but the trend is unknown.
In March 2010, Interior Secretary Salazar and President Obama
announced a landmark decision to cancel a lease sale scheduled for 2011
(in the 5.6 million acre block in Bristol Bay, southeastern Bering
Sea), and to reinstate protection for the region until 2017. However,
if exploration and drilling were authorized after 2017, it would
represent a potential threat to this DPS in its feeding grounds.
Naturally occurring biotoxins from dinoflagellates and other toxins
exist within the range of this DPS. Although humpback whale mortality
as a result of exposure has not been documented in this DPS, it has
been reported from other feeding grounds, so it is considered a
possibility. HAB occurrence is expected to increase with the growth of
various types of human- related activities, and with increasing water
temperatures. The level of confidence in exposure to HABs and in these
assertions is moderate.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
There are no planned commercial whaling activities in this DPS'
range; however, modest aboriginal hunting has been proposed in British
Columbia (Reeves, 2002). Certainty in this information is considered
relatively high and the magnitude is expected to remain stable.
This DPS is exposed to whale-watching activities in both its
feeding and breeding grounds, but at medium (Hawaii and Alaska) to low
levels (British Columbia). Adverse population effects from whale-
watching have not been documented, and overall impact of whale-watching
is expected to be low and stable.
This DPS is exposed to some scientific research activities in both
U.S. and Canadian waters, but at relatively low levels. Adverse
population effects from research activities have not been identified,
and overall impact is expected to be low and stable.
C. Disease or Predation
Evidence of killer whale attacks (15-20 percent) in the humpback
whales found in Hawaiian waters is moderate (Steiger et al., 2008) and
lower for Alaska and Canada. This is not regarded as a serious threat
to population growth. Shark predation likely occurs as well, although
evidence suggests the primary targets are the weak and unhealthy.
Certainty in this information is considered relatively high and the
magnitude is expected to remain stable.
There are no known reports of unusual disease or mass mortality
events for this DPS. Trends may increase slightly in response to other
stressors, such as warming oceans and other stressors that may
compromise immune systems.
Levels of parasitism in this population are not well known,
although approximately 2/3 of humpback whales in Hawaii show some
evidence of permanent, raised skin lesions, which may be a reaction to
an as yet unknown parasite (Mattila and Robbins, 2008). However, there
is no evidence that these ``bumps'' impact health or reproduction, or
cause mortality. Trends in the severity of this threat are unknown.
D. Inadequacy of Existing Regulatory Mechanisms
There has been a moratorium on offshore oil drilling in the waters
of Northern British Columbia since 1972, but there has also been a
recent proposal to lift the ban, driven largely by local government
(British Columbia Energy Plan, 2007). If so, this potential threat
could increase in this portion of the habitat.
A continuing source of potential adverse impacts to humpback whales
is interactions with vessels, including whale-watching and fishing
vessels. Under the authorities of section 11(f) of the ESA and section
112(a) of the MMPA, NMFS issued a final rule (66 FR 29502; May 31,
2001) effective in 2001 in waters within 200 nautical miles (370 km) of
Alaska, making it unlawful for a person subject to the jurisdiction of
the United States to (a) approach within 100 yards (91.4 m) of a
humpback whale, (b) cause a vessel or other object to approach within
100 yards (91.4 m) of a humpback whale or (c) disrupt the normal
behavior or prior activity of a whale (50 CFR 224.103(b)). Exceptions
to this rule include approaches permitted by NMFS; vessels which
otherwise would be restricted in their ability to maneuver; commercial
fishing vessels legally engaged in fishery activities; and state, local
and Federal government vessels operating in official duty. This rule
provides some protection from vessel strikes to Hawaii DPS individuals
while in their feeding grounds, though its effectiveness could be
improved by a greater enforcement presence and greater general public
awareness of the 100-yard (91.4-m) regulation, particularly with regard
to ``placing a vessel in path of oncoming humpback . . .'' and
``operate at slow safe speed when near a humpback whale.''
Vessel approach regulations are also in place for humpback whales
in Hawaiian waters (50 CFR 224.103(a)). These are similar to the Alaska
regulations, with an additional prohibition against operating any
aircraft within 1,000 feet (300 m) of any humpback whale. The
regulations were adopted in 1987 under authority of the ESA and later
amended to delete a provision that was inconsistent with the MMPA. See
52 FR 44,912 (November 23, 1987); 60 FR 3,775 (January 19, 1995)
(deleting 223.31(b) as mandated by Section 17 of the MMPA Amendments of
1994, Public Law 103-238, because the MMPA provided that approach to
100 yards (91.4 m) is legal, whereas the regulatory provision had
allowed approach only to within 300 yards (274.3 m) in cow/calf areas).
As noted above under Section 4(a)(1) Factors Applicable to All
DPSs, the Hawaiian Islands Humpback Whale National Marine Sanctuary was
established primarily to provide protections to a key North Pacific
humpback whale breeding/nursery area, and therefore, it should
contribute to reducing the extinction risk of the Hawaii DPS of the
humpback whale. Among the regulations in effect in the sanctuary are
approach regulations substantially similar to those at 50 CFR
224.103(a) (See 15 CFR 922.184). Although substantially similar, the
approach regulations effective in the sanctuary protect humpback whales
in a narrower geographic range than do the current ESA approach
regulations. Because these regulations apply only within the sanctuary,
we seek public comment on whether the sanctuary protections would be
sufficient for the protection of humpback whales from vessel
interactions throughout the Hawaiian Islands, recognizing that the
existing approach regulations at 50 CFR 224.103(a), which were adopted
under authority of the ESA only, would no longer be applicable and
would need to be removed if this rule becomes final and the Hawaii DPS
of humpback whales is not listed under the ESA (See ADDRESSES).
Commenters should consider the impacts of the Office of National Marine
Sanctuaries' recent proposal to expand the sanctuary boundaries and
strengthen the approach provisions (80 FR 16224, 16227, 16238; March
26, 2015).
In Canada, humpback whales are managed by the Department of
Fisheries and Oceans (DFO) and legally protected through the Marine
Mammal Regulations under the Fisheries Act, 1985. These regulations
make it an offense to disturb, kill, fish for, move, tag, or mark
marine mammals (ss. 5, 7,
[[Page 22335]]
11) without a valid license. In 2003, the North Pacific humpback whale
population status was assessed as ``threatened'' by the Committee on
the Status of Endangered Wildlife in Canada (COSEWIC), and in 2005 the
population was listed as ``threatened'' under Canada's Species at Risk
Act (SARA), affording it legal protection (it is an offense to kill,
harm, harass, capture or take a listed species (Section 32(1)). The
population's status was re-assessed as ``special concern'' in 2011 by
COSEWIC. Following public consultation regarding the reclassification
of the species, the DFO has referred the assessment of ``special
concern'' back to COSEWIC for further consideration, and the SARA
status of North Pacific humpback whale remains unchanged at the
publication of the 2013 Recovery Strategy (Fisheries and Oceans Canada.
2013). Should the SARA status of humpback whales remain unchanged, an
action plan to implement the 2013 recovery strategy will be completed
within 5 years of its final posting on the Species at Risk Public
Registry. Hawaii DPS whales should benefit from any protections
afforded by SARA when they are in British Columbia feeding grounds.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is suspected interaction with the herring fishery in
Southeast Alaska, but impacts to humpback whales are considered to be
modest; the level of certainty in this information is moderate and
currently under study, and impacts are considered stable because the
herring fishery is regulated. Humpback whales may compete with
fisheries in British Columbia as well, as they also have a herring
fishery, as well as a ``krill'' fishery.
Currently, two modest offshore aquaculture sites are located in
Hawaii, and their placement overlaps with humpback whale habitat.
However, there have been no known fatal interactions, and indirect
impacts from food, waste, or medicines being provided to the cultivated
species are likely to be low, as humpback whales do not feed in Hawaii.
The level of certainty in this information is high. However, if these
and other operations expand to areas of high use by the whales, at a
minimum they could physically exclude humpback whales from some of
their preferred habitat. Deep-water, finfish aquaculture in Alaska is
currently prohibited. However, some shellfish and herring ``pond''
aquaculture and salmon hatchery pens exist close to shore. There are no
known fatal encounters with this type of aquaculture in Alaska;
however, there are documented cases of humpback whales becoming
entangled in herring ``pond'' and other aquaculture gear in British
Columbia (Baird, 2003). There have been proposals to allow finfish
aquaculture in Alaska, which would increase the threat from this
activity in this portion of the DPS' range; however, Alaska State
policy is 100 percent against this. The indirect impacts of aquaculture
(e.g., on health and abundance of prey from disease or possibly habitat
disruption from poor siting) are not well known, but the BRT did not
consider these effects to be substantial and rated aquaculture as a low
threat. We are unaware of humpback whale entanglement involving
aquaculture in Hawaii or in Alaska. However, given decreasing catches
of wild fish stocks, and resulting strong incentives to expand
aquaculture in Hawaii, the threat to the Hawaii DPS posed by
aquaculture is likely to increase.
This DPS is likely exposed to moderate levels of underwater noise
resulting from human activities, which may include, for example,
commercial and recreational vessel traffic, pile driving from coastal
construction, and activities in Naval test ranges. Overall population-
level effects of exposure to underwater noise are not well established,
but exposure is likely chronic. As vessel traffic and other activities
are expected to increase, the level of this threat is expected to
increase. The level of confidence in this information is moderate.
The range of this DPS includes some centers of human activities in
both Canadian and U.S. waters. Reports of vessel collisions in Hawaii
have increased since 2003, when an extensive educational campaign and
hotline number were initiated; however the percentage of these that
result in fatality is unknown. Numerous collisions have also been
reported from Alaska and British Columbia (where shipping traffic has
increased 200 percent in 20 years) (Neilson et al., 2012). According to
a summary of Alaska ship strike records, an average of 5 strikes a year
was reported from 1978-2011 (Neilson et al., 2012). However, effects in
Alaska may be mitigated by the vessel approach regulations discussed
above (66 FR 29502; May 31, 2001; 50 CFR 224.103) and by NMFS outreach
to the cruise ship industry to share information about whale siting
locations.
The level of certainty in this information is high. Humpback whale
carcasses have been reported in many areas of Alaska, but given the
isolated nature of some of these areas, necropsies are not always
possible to determine cause of death. In addition, many carcasses
likely go unreported, thus ship strike numbers should be considered
minimum estimates. A reasonable assumption is that the level of the
threat will increase in proportion with increases in global commerce.
Although 5-10 ship strikes are reported per year in Hawaii and the
actual number of ship strikes is estimated to be potentially one order
of magnitude greater than this (Lammers et al., 2003), the BRT still
considered this threat level to be minimal, given the very large
population size, fast rate of growth observed in this DPS, the vessel
approach regulations in Alaska, and NMFS outreach to the cruise ship
industry.
Recent studies of characteristic wounds and scarring indicate that
this DPS experiences a high rate of interaction with fishing gear (20-
71 percent), with the highest rates recorded in Southeast Alaska and
Northern British Columbia (Neilson et al., 2009). However, these rates
represent only survivors. Fatal entanglements of humpback whales in
fishing gear have been reported in all areas, but, given the isolated
nature of much of their range, observed fatalities are almost certainly
under-reported and should be considered minimum estimates. Recent
studies in another humpback whale feeding ground, which has similar
levels of scarring, estimate that the actual annual mortality rate from
entanglement may be as high as 3.7 percent (Angliss and Outlaw, 2008).
There is a high level of certainty with regard to this information. The
threat is considered to be medium.
Overall population level effects from global climate change are not
known; nonetheless, any potential impacts resulting from this threat
will almost certainly increase. Climate change was not considered to be
a major risk to this DPS currently, however. The level of confidence in
the magnitude of this threat is low.
In summary, fishing gear entanglement is considered to be a medium
threat to the Hawaii DPS. All other threats are considered likely to
have no or minor impact on population size and/or the growth rate or
are unknown but assumed to be minor (based largely on the current
abundance and population growth trend) for the Hawaii DPS.
[[Page 22336]]
Mexico DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Breeding locations used by the Mexico DPS (and migratory routes to
get to aggregation areas) are adjacent to large human population
centers. The DPS may, therefore, be exposed to adverse effects from a
number of human activities, including fishing activities (possible
competition with fisheries), effluent and runoff from human population
centers as coastal development increases, activities associated with
oil and gas development, and a great deal of vessel traffic.
Southern California humpback whales were found to have the highest
levels of DDT, PCBs, and PBDEs of all North Pacific humpback whales
sampled on their feeding grounds (Elfes et al., 2010). The DDT levels
detected were greater than those found in the typically more
contaminated Gulf of Maine humpback whales, possibly due to the
historical dumping of DDT off Palos Verdes Peninsula (Elfes et al.,
2010). It is not possible to state unequivocally if population level
impacts occur as a result of these contaminant loads, but Elfes et al.
(2010) suggested the levels found in humpback whales are unlikely to
have a significant impact on their persistence as a population.
There are currently numerous active oil and energy leases and
offshore oil rigs off the U.S. west coast. Offshore LNG terminals have
been proposed for California and Baja California. The feeding grounds
for this DPS are therefore an active area with regard to energy
exploration and development. However, there are no plans at present to
open the West Coast to further drilling. Alternative energies, such as
wind and wave energy, may be developed in the future in this region.
Currently, the threat posed to this DPS by energy exploration and
development is low, and is considered stable.
Naturally occurring biotoxins from dinoflagellates and other
organisms are known to exist within the range of this DPS, though there
are no records of known humpback whale deaths attributable to biotoxin
exposure in the Pacific. The occurrence of HABs is expected to increase
with nutrient runoff associated with the growth of various types of
human-related activities. The level of certainty in the impacts of
exposure to HABs is moderate.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
No whaling currently occurs in this DPS' range.
The Mexico humpback whale DPS is exposed to some whale watching
activities in both U.S. and Mexican waters, but at low levels. Adverse
effects from whale watching have not been documented, and overall
impact of whale watching is expected to be low and stable.
This DPS is exposed to some scientific research activities in both
U.S. and Mexican waters, but at relatively low levels. Adverse effects
from research activities have not been identified, and overall impact
is expected to be low and stable.
C. Disease or Predation
With regard to natural mortality of individuals in the Mexico DPS,
humpback whales in the California feeding area had a higher incidence
of rake marks attributed to killer whale attacks (20 percent) than in
other feeding areas (Steiger et al., 2008). The BRT noted that 44
percent of all flukes photographed from the Mexico humpback whale DPS
are scarred with killer whale tooth rakes. Most of the attacks are
thought to occur on calves in breeding/calving areas, and levels
observed in the California group likely result from a propensity for
killer whale attacks in Mexican breeding areas (Steiger et al., 2008).
Though a factor in the ensured longevity of this DPS, it does not
appear to be preventing population recovery (Steiger et al., 2008). The
threat of predation was therefore ranked as low or unknown for all
DPSs.
There is little to no information on the impacts of disease or
parasites on the Mexico DPS.
D. Inadequacy of Existing Regulatory Mechanisms
Under Mexican law, all marine mammals are listed as ``species at
risk'' and are protected under the General Wildlife Law (2000).
Amendments to the General Wildlife Law to address impacts to whales by
humans include: Areas of refuge for aquatic species; critical habitat
being extended to aquatic species (including cetaceans); prohibition of
the import and export of marine mammals for commercial purposes
(enacted in 2005); and protocol for stranded marine mammals (2011).
Mexican Standard 131 on whale watching includes avoidance distances and
speeds, limits on number of boats, and protection from noise (no echo
sounders). Two protection programs for humpback whales (regional
programs for protection) have been proposed for the regions of Los
Cabos and Banderas Bay (Bahia de Banderas).
NMFS issued a final rule (66 FR 29502; May 31, 2001) effective in
2001 in waters within 200 nautical miles (370 km) of Alaska, making it
unlawful for a person subject to the jurisdiction of the United States
to (a) approach within 100 yards (91.4 m) of a humpback whale, (b)
cause a vessel or other object to approach within 100 yards (91.4 m) of
a humpback whale, or (c) disrupt the normal behavior or prior activity
of a whale. Exceptions to this rule include approaches permitted by
NMFS; vessels which otherwise would be restricted in their ability to
maneuver; commercial fishing vessels legally engaged in fishery
activities; state, local and Federal government vessels operating in
official duty; and the rights of Alaska Natives. As is true for the
Hawaii DPS, this rule provides some protection from vessel strikes to
Mexico DPS individuals while in their feeding grounds.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
This DPS is likely exposed to relatively high levels of underwater
noise resulting from human activities. These may include, for example,
commercial and recreational vessel traffic, and activities in U.S. Navy
test ranges. The overall population-level effects of exposure to
underwater noise are not well-established, but exposure is likely
chronic and at relatively high levels. As vessel traffic and other
activities are expected to increase, the level of this threat is
expected to increase. The level of confidence in this information is
moderate.
Of the 17 records of stranded whales in Washington, Oregon, and
California in the NMFS stranding database, three involved fishery
interactions, two were attributed to vessel strikes, and in five cases
the cause of death could not be determined (Carretta et al., 2010).
Specifically, between 2004 and 2008, 14 humpback whales were reported
seriously injured in commercial fisheries offshore of California and
two were reported dead. The proportion of these that represent the
Mexican breeding population is unknown. Fishing gear involved included
gillnet, pot, and trap gear (Carretta et al., 2010). Between 2004 and
2008, there were two humpback whale mortalities resulting from ship
strikes reported and eight ship strike attributed injuries for
unidentified whales in the California-Oregon-Washington stock as
defined by NMFS, and some of these may have
[[Page 22337]]
been humpback whales (Carretta et al., 2010). The Mexico DPS is known
to also use Alaska and British Columbia waters for feeding
(Calambokidis et al., 2008). Numerous collisions have been reported
from Alaska and British Columbia (where shipping traffic has increased
200 percent in 20 years) (Neilson et al., 2012). According to a summary
of Alaska ship strike records, an average of 5 strikes a year was
reported from 1978-2011 (Neilson et al., 2012). However, effects in
Alaska may be mitigated by the vessel approach regulations discussed
above (66 FR 29502; May 31, 2001) and by NMFS outreach to the cruise
ship industry to share information about whale siting locations.
Overall population level effects from global climate change are not
known; nonetheless, any potential impacts resulting from this threat
will almost certainly increase. The BRT concluded that currently
climate change is not a risk to the DPS, but the level of confidence in
the magnitude of this threat is poor.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
Mexico DPS, with the following exception: Fishing gear entanglements
are considered likely to moderately reduce the population size or the
growth rate of the Mexico DPS.
Central America DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Human population growth and associated coastal development,
including port expansions and the presence of water desalinization
plants, are some of the potential threats to the Central America DPS.
The presumed migratory route for this DPS lies in the coastal waters
off Mexico and includes numerous large and growing human population
centers from Central America north along the Mexico and U.S. coasts.
The California and Oregon feeding grounds are the most ``urban'' of all
the North Pacific humpback whale feeding grounds, resulting in
relatively constant anthropogenic exposure for the individuals of this
DPS. However, the high degree of coastal development is not preventing
the increase of humpback whales in this area, and it is considered to
be a low level threat.
Associated with this proximity to urban areas is a high level of
exposure to man-made contaminants. Elevated levels of DDTs, PCBs, and
PBPEs have been observed in ``southern California'' humpback whales;
levels were higher than observed in humpback whales from the North
Atlantic's Gulf of Maine feeding ground (Elfes et al., 2010). These
levels may be linked to historical dumping of DDTs off the Palos Verdes
Peninsula, CA (Elfes et al., 2010). However, the levels observed are
not expected to have a significant effect on population growth (Elfes
et al., 2010). DDT and PCB levels are likely to decrease in feeding
areas because use of these chemicals has been banned in the United
States, but PBDEs may still be increasing.
Energy exploration and development activities are present in this
DPS' habitat range. There are currently numerous active oil and energy
leases and offshore oil rigs off the U.S. west coast. Offshore LNG
terminals have been proposed for California and Baja California. The
feeding grounds for this DPS are therefore an active area with regard
to energy exploration and development. However, there are no plans at
present to open the West Coast to further drilling. Alternative
energies, such as wind and wave energy, may be developed in the future
in this region. Currently, the threat posed to this population by
energy exploration and development is low, and is considered stable.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Whale-watching tourism and scientific research occur, at relatively
low levels, on both the feeding and breeding grounds of the Central
America DPS as well as along the migratory route. Whale-watching is
highly regulated in U.S. waters. Many Central American countries also
have whale-watching guidelines and regulations in the breeding ground
of this population. Whale-watching is therefore not considered a threat
to this population. Scientific research activities such as observing,
collecting biopsies, photographing, and recording underwater
vocalizations of whales occurs throughout this DPS' range, though no
adverse effects from these events have been recorded.
No whaling currently occurs in this DPS' range.
C. Disease or Predation
There is little information on the impacts of disease, parasites or
algal blooms on the Central America DPS. HABs of dinoflagellates and
diatoms exist within the feeding range of this DPS, but there have been
no records of humpback whale deaths as a result of exposure. The
occurrence of HABs is expected to increase with the growth of various
types of human-related activities but does not pose a threat to this
population currently.
Though the occurrence and impacts of predation on humpback whales
is not well understood, some evidence of killer whale and shark attacks
exists for this DPS. Evidence of killer whale attacks is relatively
high in California waters, with 20 percent of humpback whales showing
scars from previous attacks (Steiger et al., 2008). Scars from attacks
are believed to have originated in the winter when whales are in
Mexican and Central American waters. However, this is not regarded as a
serious threat to population growth. Shark predation likely occurs as
well, though it is not known to what degree; it does not appear to be
adversely impacting this DPS.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the Central America DPS were
identified.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is no evidence to suggest that competition with fisheries
poses a threat to this DPS. Humpback whales in southern and central
California feed on small schooling fish, including sardine, anchovy,
and herring, all of which are commercially harvested species. In
addition, they also feed on krill, which are not harvested off the U.S.
west coast. Humpback whales are known to be foraging generalists.
Although their piscivorous prey is subject to naturally- and
anthropogenically-mediated fluctuations in abundance, there is no
indication that fishery-related takes are substantially decreasing
their food supply.
This DPS is likely exposed to relatively high levels of underwater
noise resulting from human activities, including commercial and
recreational vessel traffic, and activities in U.S. Navy test ranges.
Exposure is likely chronic and at relatively high levels. It is not
known if exposure to underwater noise affects humpback whale
populations, and this threat does not appear to be significantly
impacting current population growth.
Vessel collisions and entanglement in fishing gear pose the
greatest threat to this DPS. Especially high levels of large vessel
traffic are found in this DPS' range off Panama, southern California,
and San Francisco. Several records exist of ships striking humpback
whales (Carretta et al., 2008; Douglas et al., 2008), and it is likely
that not all
[[Page 22338]]
incidents are reported. Two deaths of humpback whales were attributed
to ship strikes along the U.S. West Coast in 2004-2008 (Carretta et
al., 2010). Ship strikes are probably underreported, and the level of
associated mortality is also likely higher than the observed
mortalities. Vessel collisions were determined to pose a medium risk
(level 2) to this DPS, especially given the small population size.
Shipping traffic will probably increase as global commerce increases;
thus, a reasonable assumption is that the level of ship strikes will
also increase.
Between 2004 and 2008, 18 humpback whale entanglements in
commercial fishing gear off California, Oregon, and Washington were
reported (Carretta et al., 2010), although the actual number of
entanglements may be underreported. Effective fisheries monitoring and
stranding programs exist in California, but are lacking in Central
America and much of Mexico. Levels of mortality from entanglement are
unknown and do vary by region, but entanglement scarring rates indicate
a significant interaction with fishing gear.
Currently there is no aquaculture activity on the feeding grounds
of this DPS, though migrating individuals may encounter some
aquaculture operations in coastal waters off Mexico. Humpback whales in
this DPS are not considered to be adversely affected by aquaculture.
Overall population level effects from global climate change are not
known; nonetheless, any potential impacts resulting from this threat
will almost certainly increase. Humpback whales feeding off southern
and central California have a flexible diet that includes both krill
and small pelagic fishes. Acidification of the marine environment has
been documented to impact the physiology and development of krill and
other calcareous marine organisms, which may reduce their abundance and
subsequent availability to humpback whales in the future (Kurihara,
2008). However, the diet flexibility of humpback whales in this region
may give this DPS some resilience to a climate change effect on their
prey base compared to Southern Hemisphere humpback whales that have a
more narrow krill-based diet. Currently, climate change does not pose a
significant threat to the growth of this DPS.
In summary, vessel collisions and fishing gear entanglements are
considered likely to moderately reduce the population size or the
growth rate of the Central America DPS. All other threats are
considered likely to have no or minor impact on population size and/or
the growth rate, or are unknown for the Central America DPS.
Brazil DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Human population growth and associated coastal development
represent potential threats to coastal populations of humpback whales.
These can take many forms, including chemical pollution, increase in
ship traffic and underwater noise levels. The coast of Brazil has
experienced various levels of human development within the range of
humpback whales. These are of greater intensity along the northeastern
coast of the country (between 5[deg] and 12[deg] S), where large human
settlements are found (the three main cities--Salvador, Recife and
Natal--have 1-3 million inhabitants and have observed population
increases of 3 percent per year since the early 1970s) (Instituto
Brasileiro de Geografia e Estat[iacute]stica, 2010). Such population
growth has resulted in a substantial rise in effluent discharge in
coastal areas used by humpback whales during the breeding season. The
stretch of the coast where the largest concentration of humpback whales
is found (Abrolhos Bank, 16[deg]-18[deg] S) has not had the same level
of human growth and is relatively pristine compared to areas farther to
the north.
There is no evidence that human population growth has had any major
direct impact on western South Atlantic humpback whales. In fact, the
Brazil DPS has shown strong signs of recovery in the same period in
which human growth occurred adjacent to the breeding grounds. Shifts in
habitat use and abundance may have occurred on a local basis, but no
studies have been conducted to assess these changes. Effects of
chemical pollution are largely minimized because these whales do not
feed in the tropical wintering grounds. The feeding grounds of this DPS
are located in relatively remote offshore areas in the Southern Ocean
where human activities have been minimal. While potential impacts are
unknown, they are probably small in these areas. The current threat of
coastal development to this population was ranked as low, but is
considered to be increasing.
The construction of new ports along the coast of Brazil has been
stimulated by the country's recent economic growth as well as the rapid
development of the oil and gas industry. Therefore, a resultant
increase in ship traffic will likely increase the probability of ship
strikes and possibly result in greater humpback whale mortality off
Brazil. The threat posed by energy exploration and development was
ranked low but increasing.
The effects of contaminants on this population are unknown. The
occurrence of HABs is expected to increase with increased run-off and
nutrient input from human-related activities; however, HABs do not pose
a threat to this population currently.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
A seasonal humpback whale-watching industry exists in some parts of
the wintering grounds off Brazil. In the Abrolhos Bank, the area of
greatest humpback whale concentration, whale-watching is usually
associated with other tourist activities. The Bank contains large coral
reef formations, and the associated biological diversity makes this
region an important diving/snorkelling center. Despite great potential,
expansion of whale-watching in this region is difficult because of poor
tourism infrastructure and because whales are far away from the coast
relative to other areas (Cipolotti et al., 2005).
A more established whale-watching industry operates farther to the
north, near Praia do Forte and Salvador. Most whale watching tours in
Bahia State depart from Praia do Forte (Hoyt and In[iacute]guez, 2008).
In other parts of the humpback wintering grounds (e.g., Ilh[eacute]us,
Itacar[eacute], Porto Seguro), whale-watching can occur in an
opportunistic fashion. Often, fishermen are hired to take groups of
tourists to see whales, but these are unregulated and occasional.
Because of the relatively small scale, whale-watching activities
possibly cause limited, if any, impact on the Brazil DPS of the
humpback whale. This threat is considered low.
There is currently no commercial whaling in this region.
This humpback whale DPS is exposed to scientific research
activities, but adverse effects from research activities have not been
identified, and overall impact is expected to be low and stable.
C. Disease or Predation
There are studies of disease in the Brazil DPS of the humpback
whale, but no indication that it presents a risk to the DPS. Stranded
whales have shown different types of bone pathologies (Groch et al.,
2005), but the incidence of these pathologies are not well known.
A recent increase in humpback whale mortality has occurred along
the coast of Brazil. The number of carcasses seen floating at sea or
found ashore in 2010
[[Page 22339]]
(96 individuals) was nearly 3 times the average for the period 2002-
2009 (29.5 individuals). Mortalities dropped in 2011 (39), but they
have increased in subsequent years (47 in 2012; 51 in 2013; 55 to date
in 2014, with not many more expected for the rest of 2014) (Milton
Marcondes, Humpback Whale Institute Brazil, pers. comm., 2014). The
causes for this increased mortality are not well understood and are
under investigation (Humpback Whale Institute Brazil, unpublished
data). However, while mortalities are high, they are not unusually
high. Despite these mortalities, the DPS appears to continue to
increase in abundance.
Killer whales appear to be one of the main predators of humpback
whales, especially of calves and immature individuals (Clapham, 2000).
While predation can represent an important source of neonatal/juvenile
mortality (Steiger et al., 2008), no studies have been conducted to
assess its effects on this DPS.
D. Inadequacy of Existing Regulatory Mechanisms
Diving with whales is prohibited by Federal law in Brazil, but
opportunistic whale-watching occurs during diving trips (Morete et al.,
2003). Most whale-watching operations are concentrated within the
Abrolhos National Park and therefore are highly controlled. The maximum
number of boats allowed within the park is 15 (Hoyt, 2000).
E. Other Natural or Manmade Factors Affecting Its Continued Existence
The threats posed by offshore aquaculture and competition with
fisheries were considered low for the Brazil DPS of humpback whales.
Entanglements in various types of fishing nets have been increasing
in the wintering areas (Zerbini and Kotas, 1998), but there is no
current estimate of mortality. Reports from fishermen indicate that a
large proportion of entanglements are comprised of calves (Zerbini and
Kotas, 1998). In the past 20 years, the number of entanglement cases
observed or reported has increased substantially as has the proportion
of whales seen in wintering grounds, with evidence (e.g., scars) of
entanglement in fishing gear (Siciliano, 1997; Groch et al., 2008)).
Interactions of humpback whales with fisheries have been observed
throughout the wintering ground, and they seem to be increasing as the
population grows and re-occupies new or historical habitats. However,
there is currently no assessment on the proportion of entanglements
resulting in mortality and no estimates of fishery-related mortality
for this DPS. The threat of entanglements was considered low but
increasing.
Ship collisions are a well-known cause of mortality in humpback
whales (Laist et al., 2001), but their incidence among humpback whales
in the Brazil DPS is not well known. Reports of collisions with whales
have been provided by fishermen and recreational boaters. In addition,
photographic/physical evidence of ship strikes has been recorded
throughout the wintering grounds off Brazil (e.g., Marcondes and Engel,
2009). These events have been increasing and seem to be correlated with
population recovery, but their conservation implications require
further studies (Bezamat et al., 2014). In areas of high whale density
(e.g., the Abrolhos Bank), collisions between whales and fishing boats
have resulted in permanent damage to the boats. The fate of whales
involved in these accidents is not known (Andriolo, unpublished data).
Ship strikes were considered a low, but increasing, threat to this DPS
of humpback whales.
The increase in coastal development and ship traffic, the
construction of new ports and the expansion of offshore oil and gas
extraction have resulted in a rise of underwater noise levels along the
breeding range of humpback whales. Concerns about effects of noise
include disruption of behavior, interference with communication,
displacement from habitats and, in extreme cases, physical damage to
hearing (Nowacek et al., 2007). Few studies have been carried out to
assess whether and how an increase in noise levels has impacted the
Brazil DPS. Research conducted in Abrolhos Bank (Sousa-Lima and Clark,
2008; Sousa-Lima and Clark, 2009) showed that the number of singing
whales diminished in the presence of low-frequency boat noise and that
singing whales stopped calling and changed direction of movement if the
sound source was within 7.5km on average. Anthropogenic noise was
considered a low, but increasing, threat to the Brazil DPS of humpback
whales.
Climate change may impact the Brazil DPS of humpback whales in
multiple ways. Sea level rise, ocean warming and ocean acidification
may all negatively impact the reef system, which provides shallow,
protected waters for breeding. Ocean acidification also has a
documented impact on krill growth and development (Kurihara, 2008), and
krill is the primary prey item for Southern Hemisphere humpback whales.
Krill are tightly associated with sea ice (Brierley et al., 1999;
Brierley et al., 2002), and decreasing sea ice may negatively impact
krill abundance and/or distribution. Decreases in krill abundance have
been observed around the Antarctic Peninsula (Atkinson et al., 2004).
Overall population level effects from global climate change and
anthropogenic noise are not well known and the threat was ranked low,
based on the premise that krill would need to be substantially reduced
in order to put humpback whales at risk of extinction. As discussed
above under Section 4(a)(1) Factors Applicable to All DPSs, the BRT did
not think the linkage between climate change and future krill
production was sufficiently well understood to rate it as moderate or
high risk. Nonetheless, any potential impacts resulting from these
threats will almost certainly increase, but not in the foreseeable
future.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
Brazil DPS.
Gabon/Southwest Africa DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
For humpback whales using the waters of central western Africa,
expanding offshore hydrocarbon extraction activity now poses an
increasing threat (Findlay et al., 2006). The degree to which humpback
whales are affected by offshore hydrocarbon extraction activity is not
known, but it is believed that long-term exposure to low levels of
pollutants and noise, as well as the drastic consequences of potential
oil spills, could have conservation implications.
The Gulf of Guinea region suffers from pollution and habitat
degradation, both from major coastal cities (Lagos, Accra, Libreville,
Porto-Nevo) that dispense raw sewage and untreated toxic waste into the
marine environment (United Nations Environment Programme, 1999), and
from unregulated foreign trawling and oil and gas developments (Chidi
Ibe, 1996). The practice of mining construction materials from the
near-shore coastal zone (e.g., sand and gravel) is also common in this
region, which contributes to habitat degradation (Chidi Ibe, 1996). The
threat of coastal development is considered low, but increasing.
Certain naturally occurring biotoxins from dinoflagellates and
other organisms may exist within the range of this DPS, although
humpback whale deaths as a result of exposure have not been documented
in this DPS. The occurrence of HABs is expected to increase with the
growth of various types of human-related activities. The
[[Page 22340]]
level of confidence in the predicted increase is moderate.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
No commercial whaling occurs in this DPS' range.
A small hunt, not regulated by the IWC, is also thought to exist in
the Gulf of Guinea at the island of Pagalu (Aguilar, 1985; Reeves,
2002). No information exists on the fishery since 1975, but as of 1970,
whales were still being taken in the area. This hunt would affect the
Gabon/Northwest Africa DPS in the breeding grounds, but we have no
information to indicate that it contributes significantly to the
extinction risk of the DPS. If there is an aboriginal hunt at Pagalu,
it is estimated to be 3 or less individuals per year.
Whale-watching in the Gulf of Guinea region is small in scale, with
small humpback whale-watching industries documented in Benin, Gabon,
S[atilde]o Tom[eacute] and Pr[iacute]ncipe (O'Connor et al., 2009).
Whale-watching in South Africa is mainly focused on right whales, with
humpback whales watched opportunistically. Boat-based whale-watching
has grown 14 percent in the last decade, and is concentrated in the
western Cape region; South Africa now numbers among the top ten
destinations for whale-watching worldwide (O'Connor et al., 2009).
Whale-watching in Namibia is primarily focused on dolphins, and has
seen 20 percent growth since 2008. The threat posed to this DPS by
whale-watching is considered low.
This humpback whale DPS is exposed to scientific research
activities, but adverse effects from research activities have not been
identified, and overall impact is expected to be low and stable.
C. Disease or Predation
There are no reports of disease in this DPS and levels of
parasitism are unknown. Predation likely occurs, though it is not known
to what degree but it does not appear to be adversely impacting this
DPS.
D. Inadequacy of Existing Regulatory Mechanisms
There are regulations in place for all whale-watching activity in
South Africa (Carlson, 2007).
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is no known/reported competition with fisheries to the Gabon/
Southwest Africa DPS; this threat is therefore considered low and
stable. The threat of offshore aquaculture is considered low.
Certain potential and real effects on cetaceans and other fauna are
expected to increase due to the growth of industry activities,
including noise disturbance from seismic surveys (Richardson et al.,
1995). Changes in their behavioral patterns or displacement from
migratory, mating, and especially important calving and nursing
habitats could impact reproductive success and calf survival during
critical stages of development.
Rapid increases in shipping and port construction throughout the
Gulf of Guinea (Van Waerebeek et al., 2007) are likely to increase the
risks of ship strikes for humpback whales. Whales are reported as
stranding in Benin, with wounds suspected as originating from ship
strikes (Van Waerebeek et al., 2007). There are no dedicated stranding
networks in the region, and ship strikes with oil tankers and other
vessels have not been documented. Collisions with vessels are not
likely to be a major threat considering the size of the DPS.
There are entanglement risks for humpback whales in these regions,
including a growing commercial shrimp industry off Gabon (Walsh et al.,
2000), and an expansion in unregulated fishing by foreign fleets in
Gulf of Guinea waters (Collins, pers. comm.; Chidi Ibe, 1996; Brashares
et al., 2004). Entanglement in fishing gear occurs, but it is not
likely to be a major threat considering the size of the DPS.
Climate change may impact the Gabon/Southwest Africa DPS of
humpback whales in multiple ways. Sea level rise, ocean warming and
ocean acidification may all negatively impact the reef system, which
provides shallow, protected waters for breeding. Ocean acidification
also has a documented impact on krill growth and development (Kurihara,
2008), and krill is the primary prey item for Southern Hemisphere
humpback whales. Krill are tightly associated with sea ice (Brierley et
al., 1999; Brierley et al., 2002), and decreasing sea ice may
negatively impact krill abundance and/or distribution. Decreases in
krill abundance have been observed around the Antarctic Peninsula
(Atkinson et al., 2004). Overall population level effects from global
climate change and anthropogenic noise are not known and the threat was
ranked low, based on the premise that krill would need to be
substantially reduced in order to put humpback whales at risk of
extinction. As discussed above under Section 4(a)(1) Factors Applicable
to All DPSs, the BRT did not think the linkage between climate change
and future krill production was sufficiently well understood to rate it
as moderate or high risk. Nonetheless, any potential impacts resulting
from these threats will almost certainly increase.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
Gabon/Southwest Africa DPS, with the exception of energy exploration
posing a moderate threat throughout the west coast of Africa.
Southeast Africa/Madagascar DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Human populations are growing rapidly in coastal areas in
Madagascar and East Africa, which may contribute, generally, to
humpback whale habitat degradation and related negative influences.
Until recently, oil and gas reserves in east Africa were largely
unexplored. However, recently, a number of offshore seismic oil and gas
surveys have been conducted in Mozambique, Tanzania, Madagascar and the
Seychelles. As a result, drilling is now either underway or planned in
all of these regions (Frynas, 2004; Findlay et al., 2006). As noted
elsewhere, such activity brings threats of increased underwater noise
from the exploration and development phases themselves, and increased
vessel activity; the possibility of an oil spill; possible habitat
degradation from such things as drill spoils and dredging; and vessel
collisions. In Madagascar, offshore development has been concentrated
on the northwest coast; in Mozambique it is concentrated in the
Mozambique Basin, Zambezi delta region, while development in Tanzania
has been most focused on coastal Zanzibar. Humpback whales occur
seasonally in all of these regions.
Levels of exposure of humpback whales in this region to various
pollutants are not known, nor is the occurrence of HABs. Trends in the
extent of this threat likewise are not known.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Whale-watching activities are growing rapidly in waters off
Mozambique; yet, these are poorly regulated (O'Connor et al., 2009).
Most of these activities are locally based and involve motorized boats,
recreational fishing boats, and dive boats. Whale-watching in South
Africa is mainly focused on right whales, although the industry at St
[[Page 22341]]
Lucia in KwaZulu Natal province is focused on southwestern Indian Ocean
humpback whales. Recent political instability in Madagascar has limited
the growth rate of whale-watching activities in this region, although
growth between 1998-2008 was still estimated at about 15 percent, with
the main industry focused on humpback whales frequenting the Ile Ste
Marie/Antongil Bay region, and over 14,000 tourists participating in
whale watch tours by 10-15 operators in 2008 (O'Connor et al., 2009).
Whale watch tourism in Mayotte is small-scale, but has expanded
rapidly, from no industry in 1998 to 10,000 annual whale watchers in
2008 (O'Connor et al., 2009), with a focus on a range of cetacean
species. In Mauritius large cetacean watching is a minimal component of
the whale watch industry and is therefore unlikely to have much impact
(O'Connor et al., 2009). An industry for watching humpback whales in
Mauritius commenced in 2008 (Fleming and Jackson, 2011).
No commercial whaling occurs in this DPS' range. This humpback
whale DPS is exposed to scientific research activities, but at low
levels. Adverse effects from research activities have not been
identified, and overall impact is expected to be low and stable.
C. Disease or Predation
There is little to no information on the impacts of disease,
parasites, or predation on this DPS.
D. Inadequacy of Existing Regulatory Mechanisms
Apparently, there are no local, national, or regional measures in
place or contemplated to reduce the impact of habitat-related threats.
There is a voluntary code of conduct for operators of whale-
watching boats in waters off Mozambique, but at present this is poorly
upheld and no formal regulations or enforcement are currently in place
(O'Connor et al., 2009). The whale-watching industry off Madagascar has
recently developed some guidelines for the protection of humpback
whales, which were passed as legislation in 2000 with local regulations
for Ile Sainte Marie (Fleming and Jackson, 2011) and Antongil Bay
(Journal Officiel de la Republique de Madagascar, 2000). In the
Mascarene Islands, the expanding whale-watching industry in La
R[eacute]union (3,000 tourists estimated in 2008) is currently
unregulated. There are regulations in place for all whale-watching
activity in South Africa (Carlson, 2007).
Fishing activities are prohibited in localized marine protected
areas in Mayotte, Moheli (in the Comoros Archipelago), Madagascar
(northeast coast), Aldabra (under protection as a UNESCO World Heritage
Site) and the coastal region between Southern Mozambique and South
Africa, so entanglement in fishing gear should not be a problem in
these areas.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Little is known/reported on interaction of humpback whales in this
DPS with fisheries, nor are there any current or planned offshore
aquaculture sites in the region. These threats are therefore considered
low and stable.
Information regarding fisheries and other activities is limited.
Kiszka et al. (2009) and Razafindrakoto et al. (2008) provided
summaries of humpback whale entanglement and strandings based on
interviews with artisanal fishing communities. Substantial gillnet
fisheries have been reported in the near-shore waters of the coasts of
mainland Africa and Madagascar; and to a lesser extent in the Comoros
Archipelago, Mayotte and Mascarene Islands, where such practices are
hindered by coral reefs and a steep continental slope bathymetry
(Kiszka et al., 2009). Stranding reports and observations from Tanzania
and Mozambique have mostly implicated gillnets, with most Madagascan
entanglements associated with long-line shark fishing (Razafindrakoto
et al., 2008). In Mayotte, humpback whales have been observed with
gillnet remains attached to them (Kiszka et al., 2009), although no
fatalities have yet been documented. Industrial fishing operations,
including longlines and drift longlines on fish aggregation devices,
purse seine and midwater trawling, occur in waters off Mauritius. The
extent of bycatch and entanglement in these waters is unknown (Kiszka
et al., 2009). Strandings and bycatch data from 2001-2005 from South
Africa indicated an estimated 15 humpback whales entangled in shark
nets (large-mesh gillnets) in KwaZulu Natal province (only one death),
while nine stranded whales were reported from the south and east coasts
(IWC, 2002b; IWC, 2003; IWC, 2004b; IWC, 2005b; IWC, 2006b).
The range of this DPS includes some growing centers of human
activities. Although there are no known records of ship struck humpback
whales in this region, the amount of vessel traffic suggests this is
probably a low-level threat. However, a reasonable assumption is that
the amount of vessel traffic, and the level of the threat, is likely to
increase as commercial shipping, recreational boating, and whale-
watching, oil and gas exploration and development, and fishing
activities increase.
This DPS is likely exposed to relatively high levels of underwater
noise resulting from human activities, including, for example,
commercial and recreational vessel traffic, and activities related to
oil and gas exploration and development. Overall population-level
effects of exposure to underwater noise are not well established, but
exposure is likely chronic and at moderate levels. As vessel traffic
and other activities are expected to increase, the level of this threat
is expected to increase. The level of confidence in this information is
moderate.
Climate change may impact the Southeast Africa/Madagascar DPS of
humpback whales in multiple ways. Sea level rise, ocean warming and
ocean acidification may all negatively impact the reef system, which
provides shallow, protected waters for breeding. Ocean acidification
also has a documented impact on krill growth and development (Kurihara,
2008), and krill is the primary prey item for Southern Hemisphere
humpback whales. Krill are tightly associated with sea ice (Brierley et
al., 1999; Brierley et al., 2002), and decreasing sea ice may
negatively impact krill abundance and/or distribution. Decreases in
krill abundance have been observed around the Antarctic Peninsula
(Atkinson et al., 2004). Overall population level effects from global
climate change and anthropogenic noise are not known and the threat was
ranked low, based on the premise that krill would need to be
substantially reduced in order to put humpback whales at risk of
extinction. As discussed above under Section 4(a)(1) Factors Applicable
to All DPSs, the BRT did not think the linkage between climate change
and future krill production was sufficiently well understood to rate it
as moderate or high risk. Nonetheless, any potential impacts resulting
from these threats will almost certainly increase.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
Southeast Africa/Madagascar DPS, with the exception of fishing gear
entanglements posing a moderate threat to the DPS.
West Australia DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
The threat posed by energy development to the Western Australia
population was considered medium
[[Page 22342]]
because of the substantial number of oil rigs and the amount of energy
exploration activity in the region inhabited by the whales (indicator
CO-26 in (Beeton et al., 2006)). Additionally, there are proposals for
many more oil platforms to be built in the near future, which are
highly likely to be executed (Department of Industry and Resources,
2008).
Coastally populated areas are increasing rapidly, and while the
threat associated with coastal development is currently considered low,
it is expected to increase. Although contaminant levels in humpback
whales in this region are unknown, the threat level was considered low
given what is known of contaminant levels in other populations.
There have been no records of humpback whale deaths as a result of
exposure to HABs in this DPS, thus the threat is considered low.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
No whaling occurs in this DPS' range.
Whale-watching tourism and scientific research occur, at relatively
low levels, throughout this DPS' range. Therefore, these threats are
considered low.
C. Disease or Predation
There are no recent studies of disease or parasitism in this DPS,
but there are no indications that they represent a substantial threat
to the DPS.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the West Australia DPS were
identified.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
Competition with fisheries is considered a low threat to humpback
whales off the coast of Western Australia due to the lack of spatial
and temporal overlap with fisheries and whales. The threat of offshore
aquaculture is considered low, but aquaculture activities may be
increasing in this region. In the Southern Hemisphere, humpback whales
feed almost entirely on krill (Euphausia superba). There is a regulated
commercial harvest of krill, but harvest levels are currently small and
there is no evidence that this threatens the food supply of humpback
whales (Everson and Goss, 1991; Nicol et al., 2008).
Coastally populated areas are increasing rapidly, with associated
development of ports bringing increased risks of ship strikes. All ship
strikes in Commonwealth waters must be reported by law, and a summary
of these has been provided to the IWC annually since 2006. Since this
time there has only been one report concerning a possible humpback ship
strike in Western Australian waters (IWC, 2009b). The threat of ship
strikes in Western Australia is considered low, but likely increasing.
There are 25 records of humpback whale entanglement events between
2003 and 2008 in this region, with western rock lobster fishing gear
most frequently implicated (Doug Coughran, pers comm.; IWC, 2004a; IWC,
2005a; IWC, 2006a; IWC, 2007c; IWC, 2008). A rise in marine fishing
debris has also been reported for the region (Environment Western
Australia, 2007), which suggests that there may be an increasing risk
of entanglement.
Climate change may impact the West Australia DPS of humpback whales
in multiple ways. Sea level rise, ocean warming and ocean acidification
may all negatively impact the reef system, which provides shallow,
protected waters for breeding. Ocean acidification also has a
documented impact on krill growth and development (Kurihara, 2008), the
primary prey item for Southern Hemisphere humpback whales. Krill are
tightly associated with sea ice (Brierley et al., 1999; Brierley et
al., 2002), and decreasing sea ice may negatively impact krill
abundance and/or distribution. Decreases in krill abundance have been
observed around the Antarctic Peninsula (Atkinson et al., 2004).
Overall population level effects from global climate change and
anthropogenic noise are not known and the threat was ranked low, based
on the premise that krill would need to be substantially reduced in
order to put humpback whales at risk of extinction. As discussed above
under Section 4(a)(1) Factors Applicable to All DPSs, the BRT did not
think the linkage between climate change and future krill production
was sufficiently well understood to rate it as moderate or high risk.
Nonetheless, any potential impacts resulting from these threats will
almost certainly increase.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
West Australia DPS, with the exception of energy exploration posing a
moderate threat throughout Western Australia.
East Australia DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Whales migrating southward to the feeding grounds, as well as a
portion of those migrating north, follow the east coast of Australia,
and many or most are confined to a narrow corridor near the coast
(Bryden, 1985; Noad et al., 2008) passing several large cities.
Increasing coastal development is possible in these areas, but they
represent a minor portion of the total migratory route. As with coastal
development, sources of pollution for the east Australia DPS are
concentrated in a few locations along the migratory route. The breeding
area for this DPS is primarily within the Great Barrier Reef Marine
Park (Chittleborough, 1965; Simmons and Marsh, 1986), which has a
comprehensive set of state and Federal protection laws. However, during
tropical floods, farmland runoff may bring significant quantities of
pollutants (pesticides, fertilizers) down several rivers that empty
into the Great Barrier Reef area (Haynes and Michalek-Wagnera, 2000).
To date there are no known documented impacts of contaminants on
humpback whale survival and fecundity. Oil and gas production occurs in
Bass Strait (Australian Government, 2006), a region used by some whales
of this DPS as they migrate to feeding grounds. Overall, these threats
were considered to pose a low risk to this DPS.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Anthropogenic disturbance of this DPS occurs primarily on the
breeding ground. Whale-watching tourism in eastern Australia
(Queensland) has seen an annual average growth rate of 8.5 percent
since 1998 (this includes boat and land-based operations and both
whale- and dolphin-watching trips; O'Connor et al., 2009). In New South
Wales, boat-based whale- and dolphin-watching has seen a 2.6 percent
increase between 2003 and 2008.
Scientific research activities on this DPS occur at the feeding
grounds, breeding grounds and along the migratory route. Photo-
identification studies, biopsy efforts and other field studies do
exist. However, adverse effects from research activities have not been
documented and threats are considered low. Finally, scientific whaling
proposed by Japan in the Antarctica feeding grounds would occur in
areas where the East Australia DPS is known to feed (Nishiwaki et al.,
2007).
[[Page 22343]]
However, at this time no whaling in these feeding grounds is occurring.
C. Disease or Predation
There is little to no information on the impacts of disease,
parasites or predation on this DPS. Evidence for killer whale
interaction is documented, and 17 percent of photo-identified humpback
whales in East Australia show scarring on their flukes, most of which
is consistent with interactions with killer whales (Naessig and Lanyon,
2004). There is no evidence to suggest that this level of predation is
outside the norm for the DPS. Given the population size and current
growth rate, disease, predation and parasitism seem unlikely to pose a
significant threat to this DPS.
D. Inadequacy of Existing Regulatory Mechanisms
Oil and gas exploration and drilling are prohibited within the
Great Barrier Reef Marine Park.
Queensland has a substantial whale-watching management program
(O'Connor et al., 2009), including restricting access to areas deemed
essential for humpback conservation, and Australia has national whale-
watching guidelines. With these regulations in place, the BRT
considered the threat level from whale-watching to be low.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is no published information on negative impacts of offshore
aquaculture, competition with fisheries, or HABs on this DPS. In the
Southern Hemisphere, humpback whales feed almost entirely on krill
(Euphausia superba). There is a regulated commercial harvest of krill,
but harvest levels are currently small and there is no evidence that
this threatens the food supply of humpback whales (Everson and Goss,
1991; Nicol et al., 2008).
Vessel collisions and entanglement in fishing gear pose the
greatest anthropogenic risks to the East Australia DPS. Thirteen ship-
strike incidents and five deaths have been reported between 2003 and
2008 (summarized in Fleming and Jackson, 2011) and an additional ship-
strike was recorded in 2009 with the whale being seriously injured
(IWC, 2010a). Both fishing vessels and commercial vessels have been
involved in these incidents. Given the probable increase in fishing,
tourism and commercial shipping, the threat is likely to increase.
Entanglements are regularly reported along the east coast of Australia
and 57 entanglements have been documented between 2003-2008, with 13
confirmed deaths (Fleming and Jackson, 2011). In addition, six humpback
whales were entangled in shark control nets and released in 2009 (IWC,
2010b). These totals are likely underestimates as not all entanglements
are reported and some are not identified to species. The majority were
recorded in shark nets and occurred along the migratory route (Fleming
and Jackson, 2011). Although not insignificant, given the population
size and estimated growth rate, the threat level posed by these factors
is considered low. Anthropogenic noise is also a possible threat to
this DPS. There are several commercial shipping routes through the
Great Barrier Reef breeding ground and along the coastal migratory
route that likely result in some underwater noise exposure. Migration
through Bass Strait would also expose whales to energy exploration and
production noise. There is no information concerning exposure of whales
to underwater military activities.
Climate change may impact the East Australia DPS of humpback whales
in multiple ways. Sea level rise, ocean warming and ocean acidification
may all negatively impact the reef system, which provides shallow,
protected waters for breeding. Ocean acidification also has a
documented impact on krill growth and development (Kurihara, 2008), the
primary prey item for Southern Hemisphere humpback whales. Krill are
tightly associated with sea ice (Brierley et al., 1999; Brierley et
al., 2002), and decreasing sea ice may negatively impact krill
abundance and/or distribution. Decreases in krill abundance have been
observed around the Antarctic Peninsula (Atkinson et al., 2004).
Overall population level effects from global climate change and
anthropogenic noise are not known and the threat was ranked low, based
on the premise that krill would need to be substantially reduced in
order to put humpback whales at risk of extinction. As discussed above
under Section 4(a)(1) Factors Applicable to All DPSs, the BRT did not
think the linkage between climate change and future krill production
was sufficiently well understood to rate it as moderate or high risk.
Nonetheless, any potential impacts resulting from these threats will
almost certainly increase.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
East Australia DPS.
Oceania DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Surface run-off from nickel strip mines causes habitat degradation
and pollution of lagoons in New Caledonia, which is one of the largest
producers of nickel globally, yet the effect on the surrounding marine
environment has been poorly monitored (e.g., de Forges et al., 1998;
Labrosse et al., 2000; Metian et al., 2005). The threat to humpback
whales in Oceania from coastal development and contaminants was
considered low overall.
The BRT considered the threats of energy exploration and
development and offshore aquaculture to the Oceania population to be
low but increasing, due to the expected growth of these activities over
the next several decades.
The level of threat posed by HABs to humpback whales in Oceania is
unknown.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Some local whaling of humpback whales was carried out in French
Polynesia (Rurutu), the Cook Islands and Tonga during the 20th century
(Reeves, 2002), but this has ceased since 1960 at Rurutu (Poole, 2002),
and since 1978 elsewhere (IWC, 1981). It does not appear that Tonga
hunted whales before Europeans arrived in the region in the 19th
century (Reeves, 2002). Tonga was used as a provisioning station for
whaling vessels from the Northern Hemisphere while they operated in the
South Pacific. Tongans then began conducting shore-based whaling in the
late 1880s or early 1900s, and increasing demand prompted new boats and
whalers to enter the growing industry (Reeves, 2002). Catch rates
(whales landed) were estimated at 10-20 whales/year for the 1950s and
1960s and at least 3-8 whales/year for the mid-1970s (Reeves, 2002). In
1979, the Tonga Whaling Act was passed after a Royal Decree in 1978,
prohibiting the catch of whales on what was originally designated as a
temporary basis pending an assessment of the population by the IWC
(Keller, 1982; Reeves, 2002; Kessler and Harcourt, 2012). However, no
whaling has been carried out in Tonga since then. It is possible that
this hunt was contributing significantly to the extinction risk of the
Oceania DPS, but since no whaling has occurred there since 1979, it is
no longer contributing to the DPS' extinction risk.
Humpback whales are under threat from unregulated scientific
whaling in
[[Page 22344]]
the Antarctic waters directly to the south of Oceania. None have been
taken to date, but an annual catch of 50 humpback whales was proposed
by Japan in the 2007/2008 season (Nishiwaki et al., 2007), as part of
its JARPA II research program. This has been held in abeyance while
Japan considers that progress is being made by the IWC in its meetings
on the ``Future of the IWC.'' It is unlikely that the proposed take of
humpback whales will be reinstated in the foreseeable future; in fact,
Japan submitted its research proposal for the Antarctic on November 19,
2014, and it did not include any humpback whales (Government of Japan,
2014).
Whale-watching tourism exists in all four of the principal survey
sites in Oceania, with strong growth in the last decade. There is no
boat-based, dedicated whale watching industry in American Samoa at
present. Humpback whales have been at particular risk from excessive
boat exposure through whale watching in the Southern Lagoon of New
Caledonia, where there are currently 24 working operators. Levels of
exposure have been unusually high (peaking during weekend periods),
with boats at a distance of less than 100m from calves 40 percent of
the time and each whale exposed to an average of 3.4 boats for 2 hours
daily (Schaffar and Garrigue, 2008). In 2008, commercial tour operators
voluntarily signed a code of conduct, and subsequent compliance with
this code has significantly reduced the level of daily exposure to
boats (South Pacific Whale Research Consortium, 2009). Whale watching
and other recreational or research-related activities were deemed by
the BRT to pose a low level of threat in this region.
C. Disease or Predation
Mattila and Robbins (2008) reported raised skin lesions along the
dorsal flanks of humpback whales in American Samoa. The lesions differ
morphologically from the `depressed' lesions caused by cookie cutter
sharks and appear to persist for long periods on the skin, rather than
either erupting or healing. There are no reports of these lesions in
whaling records, suggesting that this phenomenon is recent. The cause
of these lesions is currently unknown (Mattila and Robbins, 2008), but
they are not considered a threat to the population.
D. Inadequacy of Existing Regulatory Mechanisms
Whale sanctuaries (local waters where whaling is prohibited) have
since been declared in the Exclusive Economic Zones of French
Polynesia, Cook Islands, Tonga, Samoa, American Samoa, Niue, Vanuatu,
New Caledonia and Fiji (Hoyt, 2005), while whales are protected in New
Zealand waters under the New Zealand Marine Mammal Protection Act.
Whale watching guidelines are in place in Tonga and New Caledonia,
while boat-based whale watching in the Cook Islands, Samoa and Niue is
minimal (O'Connor et al., 2009).
E. Other Natural or Manmade Factors Affecting Its Continued Existence
There is little information available from the South Pacific
regarding entanglement with fishing gear; two humpback whales have been
observed in Tonga entangled in rope in one instance and fishing net in
another (Donoghue, pers. comm.). One humpback mother (with calf) was
reported entangled in a longline in the Cook Islands in 2007 (South
Pacific Whale Research Consortium, 2008). Entanglement scars have been
seen on humpback whales in American Samoa, but there are not enough
data to determine an entanglement rate. Available evidence suggests
that entanglement is a potential concern in regions where whales and
stationary or drifting gear in the water overlap (Mattila et al.,
2010). The threat of entanglements was ranked low for the Oceania
population.
There is little information available from the South Pacific
regarding ship strikes. This threat was ranked low but is expected to
increase as vessel activity in the region increases. Similarly, this
DPS is likely exposed to moderate levels of underwater noise resulting
from human activities, which may include, for example, commercial and
recreational vessel traffic. Overall population-level effects of
exposure to underwater noise are not well established, but as vessel
traffic and other activities are expected to increase, the level of
this threat is expected to increase.
In the Southern Hemisphere, humpback whales feed almost entirely on
krill (Euphausia superba). There is a regulated commercial harvest of
krill, but harvest levels are currently small and there is no evidence
that this threatens the food supply of humpback whales (Everson and
Goss, 1991; Nicol et al., 2008). The threat of competition with
fisheries was considered low for the Oceania DPS.
Climate change may impact the Oceania DPS of humpback whales in
multiple ways. Sea level rise, ocean warming and ocean acidification
may all negatively impact the reef system, which provides shallow,
protected waters for breeding. Ocean acidification also has a
documented impact on krill growth and development (Kurihara, 2008), the
primary prey item for Southern Hemisphere humpback whales. Krill are
tightly associated with sea ice (Brierley et al., 1999; Brierley et
al., 2002), and decreasing sea ice may negatively impact krill
abundance and/or distribution. Decreases in krill abundance have been
observed around the Antarctic Peninsula (Atkinson et al., 2004).
Overall population level effects from global climate change and
anthropogenic noise are not known and the threat was ranked low, based
on the premise that krill would need to be substantially reduced in
order to put humpback whales at risk of extinction. As discussed above
under Section 4(a)(1) Factors Applicable to All DPSs, the BRT did not
think the linkage between climate change and future krill production
was sufficiently well understood to rate it as moderate or high risk.
Nonetheless, any potential impacts resulting from these threats will
almost certainly increase.
In summary, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown for the
Oceania DPS.
Southeastern Pacific DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of Its Habitat or Range
Human population growth and associated coastal development,
including port development, disruption and possible partitioning of the
marine habitat and increased turbidity in coastal waters, are potential
threats to the Southeastern Pacific DPS. The presumed migratory route
for this population lies in the coastal waters off Costa Rica, Panama,
Colombia, Ecuador, Peru, and Argentina and includes some large human
population centers in both Central and South America. Currently, the
high degree of coastal development in this DPS' habitat is not
substantially affecting the DPS' size or growth rate, and it is
considered to be a low-level threat.
Little has been published regarding contaminant levels in this
region. However, while levels of DDTs, PCBs, and PBPEs are typically
lower in Southern Hemisphere feeding areas than off the east or west
coasts of the United States, little research has been done to confirm
lower contaminant levels among Southern Hemisphere whales (Fleming and
Jackson, 2011). DDT and PCB levels are likely to decrease in feeding
areas because use of these chemicals has been banned in many
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countries, but PBPE use may still be increasing. Man-made contaminants
are not considered to be a significant threat to this population.
Energy exploration and development activities are present in this
DPS' habitat range. Oil and gas production is currently increasing in
the Gulf of Guayaquil, Ecuador (F[eacute]lix and Haase, 2005). A large
number of oil tankers transit through the Straits of Magellan yearly, a
notoriously difficult route to navigate. At least one oil spill has
resulted from a ship running aground there (Morris, 1988). Energy
development is likely to expand if oil and gas reserves are discovered
in other locations, but it does not pose a threat to this population
now or in the foreseeable future.
HABs of dinoflagellates and diatoms exist within the feeding range
of this DPS, but there have been no records of humpback whale deaths as
a result of exposure in this area. The occurrence of HABs is expected
to increase with increased run-off and nutrient input from human-
related activities; however, HABs do not pose a threat to this DPS now
or in the foreseeable future.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Whale-watching tourism and scientific research occur, at relatively
low levels, throughout this DPS' range. Whale-watching tourism occurs
along all of the South and Central American countries bordering the
habitat of this DPS. Whale-watching industry growth has been
significant and approximately half of these countries have whale-
watching guidelines in place (Hoyt and In[iacute]guez, 2008). Though
some change in behavior of whales near tourism boats has been noted,
whale-watching does not pose a threat to this DPS currently. Scientific
research activities such as observation, biopsying, photographic
studies and recording of underwater vocalizations of whales occur in
both the breeding and feeding habitats and along this DPS' migratory
route, though no adverse effects from these events have been recorded.
No whaling occurs in this DPS' range.
C. Disease or Predation
There is little information available on the impacts of disease or
parasitism on this DPS.
Predation does not appear to be a current threat to this DPS.
Killer whale attacks on humpback whales have been observed in this
region, and scarring from killer whale and potentially false killer
whale and shark attacks has been documented from photographic
catalogues (Fl[oacute]rez-Gonz[aacute]lez et al., 1994; Scheidat et
al., 2000; F[eacute]lix and Haase, 2001). The scarring rate is lower
than in some other DPSs.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the Southeastern Pacific DPS
were identified.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
In the Southern Hemisphere, humpback whales feed almost entirely on
krill (Euphausia superba). There is a regulated and growing commercial
krill fishery, but harvest levels are currently small and there is no
evidence that this threatens the food supply of humpback whales
(Everson and Goss, 1991; Nicol et al., 2008).
Aquaculture activities are high in waters of Argentina and Chile,
but the impact of these activities on this DPS of humpback whales has
not been documented and is likely low if few whales use these inland
areas. Entanglement was determined to pose a medium threat to this DPS
based on stranding and entanglement observations and spatial and
temporal overlap with aquaculture activities.
This DPS is likely exposed to relatively high levels of underwater
noise resulting from human activities, including commercial and
recreational vessel traffic, and activities in naval test ranges, and
these levels are expected to increase. Especially high levels of large
vessel traffic are found off Panama (over 12,000 ship transits
annually) and in the Magellan Straits. Naval exercises occur around
much of the South American coast annually. It is not known if
underwater noise exposure affects humpback whale populations, but this
does not currently appear to pose a significant threat to this DPS.
No ships have reported striking humpback whales in this region, but
incidents may be under-reported, and stranding reports indicate some
contribution from vessel collisions (Capella Alzueta et al., 2001;
Castro et al., 2008). Shipping traffic will probably increase as global
commerce increases; thus, a reasonable assumption is that the level of
vessel collisions will increase. Currently, ship strikes are considered
a low level threat to this DPS.
Entanglement in fishing gear poses the most significant risk to
this DPS. The majority of entanglements involve gillnets and purse
seines (F[eacute]lix et al., 1997; Capella Alzueta et al., 2001; Alava
et al., 2005; Castro et al., 2008). The artisanal fishing fleet in
Ecuador numbers over 15,000 vessels. Scarring rates indicate that close
to one third of all observed animals have experienced some level of
entanglement (Alava et al., 2005). These scarring rates are similar to
those observed off the northeast coast of the United States. Less
research effort in the Southeast Pacific region compared to the
northeast coast of the United States suggests that this reported
scarification rate may even be an underestimate of the actual level of
entanglement occurring in the Southeast Pacific. The number of dead and
entangled whales off Colombia has increased over the last two decades
(Capella Alzueta et al., 2001). Calves comprise over half of all
observed entanglement events, a disproportionate value in light of the
calf to adult ratio in the DPS (Engel et al., 2006; Neto et al., 2008).
Humpback whales in the Southern Hemisphere feed almost entirely on
krill (Euphausia superba) and acidification of the marine environment
has been documented to impact the physiology and development of krill
and other calcareous marine organisms, potentially reducing their
abundance and subsequent availability to humpback whales in the future.
The life cycle of Euphausia superba is tied to sea ice, making this
prey species vulnerable to warming effects from climate change.
Decreases in krill abundance have been observed around the Antarctic
Peninsula (Atkinson et al., 2004). Overall population level effects
from global climate change and anthropogenic noise are not known and
the threat was ranked low, based on the premise that krill would need
to be substantially reduced in order to put humpback whales at risk of
extinction. As discussed above under Section 4(a)(1) Factors Applicable
to All DPSs, the BRT did not think the linkage between climate change
and future krill production was sufficiently well understood to rate it
as moderate or high risk. Nonetheless, any potential impacts resulting
from these threats will almost certainly increase.
In summary, fishing gear entanglements are likely to moderately
reduce the population size or the growth rate of the Southeastern
Pacific DPS, and all other threats are considered likely to have no or
minor impact on population size and/or the growth rate or are unknown
for the Southeastern Pacific DPS.
[[Page 22346]]
Arabian Sea DPS
A. The Present or Threatened Destruction, Modification, or Curtailment
of its Habitat or Range
The BRT determined that the threat posed by energy exploration to
the Arabian Sea DPS should be classified as high, given the small
population size and the present levels of energy activity. A
catastrophic event similar to that of the Deepwater Horizon Oil Spill
in the Gulf of Mexico could be devastating to this DPS, especially in
light of the year-round presence of humpback whales in this area.
The effect of pollutants on cetaceans is a concern in the region,
as the Arabian Sea is a center of intense human activity with poor sea
circulation, so pollutants can persist for long periods (Minton, 2004).
Since the 1970s, the coastal and marine infrastructure in Oman has
developed at a rapid rate, with over 80 percent of the population now
living within 13 miles from the coast, and expanding development of oil
and gas resources and fishing fleets (Minton, 2004). The threats from
coastal development and contaminants are ranked low but increasing.
B. Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
This humpback whale DPS is exposed to minimal scientific research
and whale-watching activities. The adverse effects from these
activities have not been identified, and overall impact is expected to
be low and stable.
No commercial whaling occurs in this DPS' range, although 238
humpback whales were illegally killed in the Arabian Sea by the USSR in
1966 (Mikhalev, 1997).
C. Disease or Predation
Liver damage was detected in 68.5 percent of necropsied humpback
whales in this area during Soviet whaling in 1966, with degeneration of
peripheral liver sections, cone-shaped growths up to 20 cm in diameter
and blocked bile ducts (Mikhalev, 1997). While this pathology was
consistent with infection by trematode parasites, none were identified
during necropsy, and the causes of this liver damage remain unknown.
Poisonous algal blooms and biotoxins have been implicated in some
mass fish, turtle, and possibly cetacean, mortality events on the Oman
coast, although no events have yet been known to include humpback
whales. Coastal run-off from industrial activities is likely to be
increasing rapidly, while regular oil spills in shipping lanes from
tankers also contribute to pollution along the coast (e.g., Shriadah,
1999). Tattoo skin lesions were observed in 26 percent of photo-
identified whales from Oman (Baldwin et al., 2010). While not thought
to be a common cause of adult mortality, it has been suggested that
tattoo skin disease may differentially kill neonates and calves that
have not yet gained immunity (Van Bressem et al., 2009). The authors
also suggested that this disease may be more prevalent in marine mammal
populations that experience chronic stress and/or are exposed to
pollutants that suppress the immune system.
D. Inadequacy of Existing Regulatory Mechanisms
No regulatory mechanisms specific to the Arabian Sea DPS were
identified.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
The primary prey of humpback whales in Oman (Sardinella sp.) is
also consumed by tuna and other commercial pelagic fish targeted by
gillnet fisheries, but the severity of the threat of competition with
fisheries is unknown.
The BRT did not have information about offshore aquaculture
activities in the Arabian Sea.
Humpback whales in the Arabian Sea are exposed to a high level of
vessel traffic (Baldwin, 2000; Minton, 2004; Kaluza et al., 2010), so
the threat of ship strikes was considered medium for this small DPS.
This DPS is likely exposed to relatively high levels of underwater
noise resulting from human activities, including, for example,
commercial and recreational vessel traffic, and activities related to
oil and gas exploration and development. Overall population-level
effects of exposure to underwater noise are not well-established, but
exposure is likely chronic and at moderate levels. As vessel traffic
and other activities are expected to increase, the level of this threat
is expected to increase.
There is high fishing pressure in areas off Oman where humpback
whales are sighted. Eight live humpback whale entanglement incidents
were documented between 1990 and 2000, involving bottom set gillnets
often with weights still attached and anchoring the whales to the ocean
floor (Minton, 2004). Minton et al. (2010b) examined peduncle
photographs of humpback whales in the Arabian Sea and concluded that at
least 33 percent had been entangled in fishing gear at some stage. The
threat of fishing gear entanglements in the Arabian Sea is considered
high and increasing.
The threat posed by climate change to the Arabian Sea DPS of the
humpback whale was determined to be slightly higher than to the other
DPSs and was assigned medium threat level. This higher threat level is
based on the more limited movement of this DPS that both breeds and
feeds in the Arabian Sea. Changing climatic conditions may change the
monsoon-driven upwelling that creates seasonal productivity in the
region. While Northern Hemisphere individuals may be able to adapt to
climatic changes by moving farther north, Arabian Sea individuals have
less flexibility for expanding their range to cooler regions.
Evidence that this DPS has undergone a recent genetic bottleneck
and is currently at low abundance (Minton et al., 2010b) suggests that
there may be an additional risk of impacts from increased inbreeding
(which may reduce genetic fitness and increase susceptibility to
disease). At low densities, populations are more likely to suffer from
the ``Allee'' effect, where inbreeding and the heightened difficulty of
finding mates reduces the population growth rate in proportion with
reducing density.
In summary, the Arabian Sea DPS faces unique threats, given that
the whales do not migrate, but instead feed and breed in the same,
relatively constrained geographic location. Energy exploration and
fishing gear entanglements are considered likely to seriously reduce
the population's size and/or growth rate, and disease, vessel
collisions, and climate change are likely to moderately reduce the
population's size or growth rate.
Ongoing Conservation Efforts
When considering the listing, reclassification, or delisting of a
species, section 4(b)(1)(A) of the ESA requires us to consider efforts
by any State, foreign nation, or political subdivision of a State or
foreign nation to protect the species. Such efforts would include
measures by Native American tribes and organizations, local
governments, and private organizations. Also, Federal, tribal, state,
and foreign recovery actions (16 U.S.C. 1533(f)), and Federal
consultation requirements (16 U.S.C. 1536) constitute conservation
measures. We must evaluate any conservation efforts that have not yet
been implemented or have not yet been shown to be effective under the
joint NMFS/FWS Policy on the Evaluation of Conservation Efforts (PECE)
(68 FR 15100; March 28, 2003). For these efforts, we must evaluate the
certainty of
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implementing the conservation efforts and the certainty that the
conservation efforts will be effective on the basis of whether the
effort or plan establishes specific conservation objectives, identifies
the necessary steps to reduce threats or factors for decline, includes
quantifiable performance measures for the monitoring of compliance and
effectiveness, incorporates the principles of adaptive management, and
is likely to improve the species' viability at the time of the listing
determination.
The Convention on the Conservation of Migratory Species of Wild
Animals (CMS) is an intergovernmental treaty which requires range
states to protect migratory species including humpback whales where
they occur, conserve or restore habitats, mitigate obstacles to
migration, and control other endangering factors. The humpback whale is
listed in Appendix I of the CMS (species in danger of extinction
throughout all or a significant portion of their range). Parties to CMS
are required to prohibit take of Appendix I species. The CMS has
developed binding Agreements and nonbinding Memoranda of Understanding
(MOU). An MOU for the Conservation of Cetaceans and their Habitats in
the Pacific Islands Regions became effective in 2006 and offers a level
of protection to the Southern Hemisphere populations of humpback whales
and their habitats in this region. The CMS Agreements on the
Conservation of (a) Small Cetaceans in the Baltic, North East Atlantic,
Irish and North Seas (29.03.1994) and (b) Cetaceans of the Black Seas,
Mediterranean and Contiguous Atlantic Area are not designed
specifically for the humpback whale but may provide incidental
protection to the species.
The Bern Convention on the Conservation of European Wildlife and
Habitats is a regional European treaty on conservation of wild flora
and fauna and their natural habitats and calls for signatories to
provide special protection for fauna species listed in Appendix II and
III to the convention. The convention is a binding agreement for
participating parties, and its aim is to ensure conservation by means
of cooperation, including efforts to protect migratory species. The
Parties promote national policies and education for the conservation of
nature and the integration of conservation into environmental policies.
The humpback whale is listed in Appendix II--fauna species to be
strictly protected--which prohibits deliberate capture and killing,
damage to or destruction of breeding sites, deliberate disturbance of
animals during breeding and rearing, and the possession of and internal
trade in these animals alive or dead (Council of Europe's Bern
Convention, 2013).
The provisions of the Council of the European Union (EU) Directive
92/43 on the Conservation of Natural Habitats and of Wild Fauna and
Flora (EU Habitats Directive) are intended to promote the conservation
of biodiversity in EU member countries. EU members meet the habitat
conservation requirements of the network known as Natura 2000. Humpback
whales are listed in Annex IV of the convention, which identifies
species determined to be in need of strict protection across the
European region. Twenty-seven member states work with the same
legislative framework to protect species. Actions originating from the
EU Habitats Directive that may provide protection to humpback whales in
the region include (a) coordinated development of a European Red List
of species threatened at the European level (parallel with the IUCN
listings); (b) guidance documents on the protection of species listed
under the Directive, and on the development of a network of
conservation areas in the offshore marine environment and (c) species
assessment reports. While not regulatory in nature, these actions are
designed to reduce threats and provide a conservation benefit to the
Atlantic humpback whales.
The Commission for the Conservation of Antarctic Marine Living
Resources (CCAMLR) was established in 1982 with 25 member countries.
Its objective is the conservation of Antarctic marine life,
particularly krill and the Antarctic marine ecosystems that depend on
krill. The Commission manages fisheries for Antarctic krill and several
finfish species with the goal of ensuring long-term sustainability and
existing ecological relationships.
Numerous additional international or regional treaties, conventions
and agreements offer some degree of protection for humpback whales and
their habitat (reviewed by Hoyt, 2011).
In addition to IWC regulations discussed above under the Section
4(a)(1) factors, the IWC co-ordinates and funds conservation work on
many species of cetaceans. This includes work to reduce the frequency
of ship strikes, to co-ordinate disentanglement events, and to
establish Conservation Management Plans for key species and
populations. Recently, the IWC has adopted a Strategic Plan for Whale
Watching so as to facilitate the further development of this activity
in a way which is responsible and consistent with international best
practice (http://iwc.int/history-and-purpose, accessed February 10,
2014). It is too early to evaluate the effectiveness of this plan under
the PECE, but since the impact of whale-watching on all of the humpback
whale DPSs is considered to be negligible, even if this plan proves to
be extremely effective in reducing impacts of whale-watching on
humpback whales, we would not likely conclude that this plan would make
the difference between endangered and threatened status or between
threatened and not warranted status for any of the humpback whale DPSs.
At this time, we are not aware of any other formalized conservation
efforts for humpback whales that have yet to be implemented, or which
have recently been implemented but have yet to show their effectiveness
in removing threats to the species. Therefore, we do not need to
evaluate any other conservation efforts under the PECE.
Rationale for Revising the Current Global Listing and Replacing It With
Listings of DPSs
As explained throughout this proposed rule, we have determined
that, based on the best currently available scientific and commercial
information including the BRT's recommendations and consideration of
the uncertainty involved in its recommendation to identify the Okinawa/
Philippines and Second West Pacific populations as separate DPSs, the
humpback whale should be recognized under the ESA as a set of 14
separate DPSs. Based on a comprehensive status review and our analysis
of demographic factors and the Section 4(a)(1) factors, we have
concluded that some of the DPSs qualify as endangered species, some
qualify as threatened species, and some do not qualify for listing. Our
proposed action here is prompted both by our own review, begun in 2009,
and the two delisting petitions we received.
Our proposed determinations are based on the best available
scientific and commercial information pertaining to the species
throughout its range and within each DPS. In this proposed rule, we are
identifying 14 DPSs, making listing determinations for each of these
DPSs, and proposing to revise the current listing to reflect the new
determinations. We find that the purposes of the ESA would be furthered
by managing this wide-ranging species as separate units under the DPS
authority, in order to tailor protections of the ESA to those
populations that warrant protection. Based on a review of the
demographics of these DPSs and the five factors contained in ESA
section 4(a)(1), we find that the best available science no longer
supports a finding that the species is an ``endangered
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species'' throughout its range. We propose to revise the listing for
the humpback whale by removing the current species-wide listing and in
its place listing 2 DPSs as threatened and 2 as endangered. Ten DPSs
are not being proposed for listing because their current status does
not warrant listing. Since these DPSs are not currently listed as
separate entities, we are proposing to replace the existing listing of
the species with separate listings for those DPSs that warrant
classification as threatened or endangered, rather than ``delisting''
those DPSs that do not warrant such classification under our
regulations (50 CFR 424.11(d)). However, the effect of our proposed
action, if finalized, will be that the protections of the ESA will no
longer apply to these 10 DPSs. We note that we have previously
reclassified a species into constituent populations and revised the
listing to remove one population from the list or assign different
statuses to the different populations (e.g., identifying western and
eastern populations of the gray whale and removing the eastern one from
the endangered species list (59 FR 31094; June 16, 1994); identifying
western and eastern DPSs of the Steller sea lion, which had been listed
as threatened, and listing the western DPS as endangered (62 FR 24345;
May 5, 1997)).
The ESA gives us authority to make these listing determinations and
to revise the lists of endangered and threatened species to reflect
these determinations. Section 4(a)(1) of the ESA authorizes us to
determine by regulation whether ``any species,'' which is expressly
defined to include species, subspecies, and DPSs, is endangered or
threatened based on certain factors. Review of the status of a species
may be commenced at any time, either on our own initiative through a
status review or in connection with a 5-year review under Section
4(c)(2), or in response to a petition. A DPS is not a scientifically
recognized entity, but rather one that is created under the language of
the ESA and effectuated through our 1996 DPS Policy. We have some
discretion to determine whether a species should be reclassified into
DPSs and what boundaries should be recognized for each DPS. At the
conclusion of the listing review process, Section 4(c)(1) gives us
authority to update the lists of endangered species and threatened
species to conform to our most recent determinations. This can include
revising the lists to remove a species from the lists or reclassifying
the listed entity.
Neither the ESA nor our regulations explicitly prescribe the
process we should follow where the best available scientific and
commercial information indicates that the listing of a taxonomic
species should be updated and revised into listings of constituent
DPSs. To the extent it may be said that the statute is ambiguous as to
precisely how the updated listings should replace the original listing
in such circumstances, we provide our interpretation of the statutory
scheme. The purposes of the statute are furthered in certain situations
where the agency has determined that it is appropriate to revise a
rangewide listing in order to ensure that the current lists of
endangered and threatened species comport with the best available
scientific and commercial information. For example, updating a listing
may further the statute's purpose of recognizing when the status of a
listed species has improved to the point that fewer protections are
needed under the ESA, allowing for appropriately tailored management
for the populations that do not warrant listing and for those remaining
populations that do. Where a species, subspecies, or DPS no longer
needs protection of the ESA, removing those protections may free
resources that can be devoted to the protection of other species.
Conversely, disaggregating a listing into DPSs can also sometimes lead
to greater protections if one or more constituent DPSs qualify for
reclassification to endangered.
There is no practicable alternative to simultaneously recognizing
the newly identified DPSs and proposing to assign them the various
statuses of threatened, endangered, or not warranted for listing to
replace the original taxonomic species listing. It would be nonsensical
and contrary to the statute's purposes and the best available science
requirement to attempt to first separately list all the constituent
DPSs; the best available scientific and commercial information would
not support listing all of the DPSs now in order to delist some of them
subsequently. Nor would it make sense to attempt to first ``delist''
the species-level listing in order to then list some of the constituent
DPSs. Where multiple DPSs qualify for listing as endangered or
threatened, it would inherently thwart the statute's purposes to remove
protections of the ESA from all members of the species even
temporarily. The approach we are proposing ensures a smooth transition
from the current taxonomic species listing to the future listing of
certain specified DPSs.
After we consider public comment, if we publish a final rule that
has the effect of removing specified DPSs from the endangered species
list, we will continue to monitor the status of the entire range of the
humpback whale. For any DPSs that are listed, monitoring is as a matter
of course, pursuant to the obligation to periodically review the status
of these species (ESA Section 4(c)(2)). In addition, we will undertake
monitoring of any DPSs that are not listed as a result of their
improved status (ESA Section 4(g)).
Conclusions on the Status of Each DPS Under the ESA
Based on the BRT's DPS conclusions (with the exception that we
combined the Okinawa/Philippines and Second West Pacific populations
identified by the BRT into the Western North Pacific DPS), the BRT's
assessment of the demographic and ESA section 4(a)(1) factors, and our
evaluation of ongoing conservation efforts, we make the following
listing determinations.
Endangered DPSs
We conclude that 2 humpback whale DPSs are in danger of extinction
throughout their ranges: The Cape Verde Islands/Northwest Africa DPS
and the Arabian Sea DPS.
Little is known about the total size of the Cape Verde Islands/
Northwest Africa DPS, and its trend is unknown. For the Cape Verde
Islands/Northwest Africa DPS, the threats of HABs, disease, parasites,
vessel collisions, fishing gear entanglements and climate change are
unknown. All other threats to this DPS are considered likely to have no
or minor impact on the population size and/or growth rate. The BRT
distributed 32 percent of its likelihood points for this DPS to the
``high risk of extinction'' category, 43 percent to the ``moderate risk
of extinction'' category, and 25 percent to the ``not at risk of
extinction'' category. We have no reason to believe that this DPS'
status has improved since humpback whales within the range of this DPS
were listed as endangered. Because of the high likelihood that the
abundance of this DPS is low and the considerable uncertainty regarding
the risks of extinction of this DPS due to a general lack of data, we
propose to retain the Cape Verde Islands/Northwest Africa DPS on the
list of endangered species at 50 CFR 224.101.
The estimated abundance of the Arabian Sea DPS is less than 100,
but its entire range was not surveyed, so it could be somewhat larger.
Its trend is unknown. The Arabian Sea DPS faces unique threats, given
that the whales do
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not migrate, but instead feed and breed in the same, relatively
constrained geographic location. Energy exploration and fishing gear
entanglements are considered likely to seriously reduce the
population's size and/or growth rate, and disease, vessel collisions
and climate change are likely to moderately reduce the population's
size or growth rate. The BRT distributed 87 percent of its likelihood
points for the Arabian Sea DPS in the ``at high risk of extinction''
category. We agree with the BRT that the Arabian Sea DPS is at a high
risk of extinction, and therefore, we propose to retain the Arabian Sea
DPS on the list of endangered species at 50 CFR 224.101.
Threatened DPSs
We conclude that 2 other DPSs are likely to become in danger of
extinction in the foreseeable future throughout their ranges: The
Western North Pacific DPS and the Central America DPS. As noted above,
in making this determination, we applied the same 60-year timeframe as
the BRT assumed for the foreseeable future.
The abundance of the Western North Pacific DPS is thought to be
about 1,100 individuals or more, with unknown trend. All threats are
considered likely to have no or minor impact on population size and/or
the growth rate or are unknown, with the following exceptions: Energy
development, whaling, competition with fisheries, and vessel collisions
are considered likely to moderately reduce the population size or the
growth rate of the Okinawa/Philippines portion of this DPS. Fishing
gear entanglements are considered likely to seriously reduce the
population size or the growth rate of the Okinawa/Philippines portion
of this DPS. In general, there is great uncertainty about the threats
facing the Second West Pacific portion of this DPS. The BRT distributed
36 percent of its likelihood points for the Okinawa/Philippines portion
of the DPS in the ``high risk of extinction'' category and 44 percent
in the ``moderate risk of extinction'' category, with only 21 percent
of the points in the ``not at risk of extinction'' category. The
distribution of likelihood points among the risk categories indicates
uncertainty. There was also considerable uncertainty regarding the risk
of extinction of the Second West Pacific portion of this DPS, with 14
percent of the points in the ``high risk of extinction'' category, 47
percent in the ``moderate risk of extinction'' category, and 39 percent
in the ``not at risk of extinction'' category. The majority of
likelihood points were in the ``moderate risk of extinction'' category
for both portions of the Western North Pacific DPS. Given the
relatively low population size of the Western North Pacific DPS
(estimated to be less than 2,000), the moderate reduction of its
population size or growth rate likely from energy development, whaling,
competition with fisheries, and vessel collisions, the serious
reduction of its population size or growth rate likely from fishing
gear entanglements, the fact that the majority of the BRT's likelihood
points were in the ``moderate risk of extinction'' category for both
portions of the DPS, and the considerable uncertainty associated with
this, we propose to add the Western North Pacific DPS to the list of
threatened species at 50 CFR 223.102.
The abundance of the Central America DPS is thought to be about 500
individuals with unknown trend. All threats are considered likely to
have no or minor impact on population size and/or the growth rate or
are unknown, with the following exceptions: Vessel collisions and
fishing gear entanglements are considered likely to moderately reduce
the population size or the growth rate of the Central America DPS. The
BRT distributed 28 percent of its likelihood points for the Central
America DPS in the ``high risk of extinction'' category, 56 percent in
the ``moderate risk of extinction'' category, and 16 percent in the
``not at risk of extinction'' category, but the distribution of votes
among the risk categories indicates uncertainty. Given the relatively
low population size (estimated to be about 500), the moderate reduction
of its population size or growth rate likely from vessel collisions and
fishing gear entanglement, the fact that the majority of the BRT's
likelihood points were in the ``moderate risk of extinction'' category,
and the high uncertainty associated with this, we propose to add the
Central America DPS to the list of threatened species at 50 CFR
223.102.
Pursuant to the second sentence of section 4(d) of the ESA, we
propose to extend the prohibitions of Section 9(a)(1)(A) through
9(a)(1)(G) of the ESA (16 U.S.C. 1538) relating to endangered species
to the Western North Pacific and Central America DPSs of the humpback
whale.
DPSs Not Warranted for Listing Under the ESA
Finally, we conclude that 10 DPSs are neither in danger of
extinction throughout all or a significant portion of their ranges nor
likely to become so in the foreseeable future: West Indies, Hawaii,
Mexico, Brazil, Gabon/Southwest Africa, Southeast Africa/Madagascar,
West Australia, East Australia, Oceania, and Southeastern Pacific DPSs.
When the BRT first reached its conclusions regarding whether any
portions of the ranges of these DPSs were significant, NMFS and the FWS
had not yet finalized the SPOIR policy. The draft SPOIR policy that the
BRT followed differed from the final SPOIR policy in that a portion of
the range of a species was considered ``significant'' if the portion's
contribution to the viability of the species was so important that,
without that portion, the species would be in danger of extinction
throughout all of its range. The difference between the draft and final
policies is the threshold at which we determine whether a portion is
significant. Under the final SPOIR policy the hypothetical loss of the
portion being considered would only need to result in the species being
threatened throughout its range instead of endangered throughout its
range to be considered significant. Before finalizing its report, the
BRT was provided with a draft of the final SPOIR policy, which included
this lower threshold of ''threatened'' for determining whether a
portion is significant. Based on the revised SPOIR policy, the BRT
revisited its SPOIR determinations and concluded for all DPSs that were
at low or no risk of extinction, ``The ``significant portion of its
range'' analyses under the final policy would not have resulted in
different conclusions from the analyses conducted under the draft
policy.''
In the North Atlantic, the abundance of the West Indies DPS is much
greater than 2,000 individuals and is increasing moderately. The
threats of HABs, vessel collisions, and fishing gear entanglements are
likely to moderately reduce the population size and/or the growth rate
of the West Indies DPS. All other threats, with the exception of
climate change (unknown severity), are considered likely to have no or
minor impact on population size or the growth rate of this DPS. The BRT
distributed 82 percent of its likelihood points for the West Indies DPS
to the ``not at risk of extinction'' category and 17 percent to the
``moderate risk of extinction'' category. Given the large population
size (>2,000), moderately increasing trend, and the high percentage of
likelihood points allocated to the ``not at risk of extinction''
category, we conclude that, despite the moderate threats of HABs,
vessel collisions, and fishing gear entanglements and unknown severity
of climate change as a threat, the West Indies DPS is not in danger of
extinction throughout its
[[Page 22350]]
range or likely to become so in the foreseeable future throughout its
range.
Next, per the SPOIR Policy, we need to determine whether the West
Indies DPS is in danger of extinction or likely to become so in the
foreseeable future in a significant portion of its range. The BRT noted
that there are some regional differences in threats for the West Indies
DPS, but it was unable to identify portions of the DPS that both faced
particularly high threats and were so significant to the viability of
the DPS as a whole that, if lost, would result in the remainder of the
DPS being at high risk of extinction. We agree with the BRT's
conclusions and conclude that there are no portions of the DPS that
face particularly high threats and are so significant to the viability
of the DPS that, if lost, the DPS would be in danger of extinction or
likely to become so in the foreseeable future. Therefore, we conclude
that the DPS is not in danger of extinction in a significant portion of
its range, nor likely to become so in the foreseeable future.
We conclude that the West Indies DPS is not endangered or
threatened throughout all or a significant portion of its range, and,
therefore, we do not propose to list the West Indies DPS as a
threatened or endangered species.
In the North Pacific, the abundances of the Hawaii and Mexico DPSs
are much greater than 2,000 individuals and are thought to be
increasing moderately. All threats are considered likely to have no or
minor impact on population size and/or the growth rate of these two
DPSs or are unknown, with the following exceptions: Fishing gear
entanglements are considered likely to moderately reduce the population
size or the growth rate of the Hawaii and Mexico DPSs. The BRT
distributed 98 percent and 92 percent of its likelihood points for the
Hawaii and Mexico DPSs, respectively, to the ``not at risk of
extinction'' category. Given the large population size (>2,000),
moderately increasing trend, and high percentage of likelihood points
allocated to the ``not at risk of extinction'' category for both the
Hawaii and Mexico DPSs, we conclude that, despite the moderate threat
of fishing gear entanglements, the Hawaii and Mexico DPSs are not in
danger of extinction throughout their ranges or likely to become so in
the foreseeable future.
Next, per the SPOIR Policy, we need to determine whether the Hawaii
and Mexico DPSs are in danger of extinction or likely to become so in
the foreseeable future in a significant portion of their ranges. The
BRT noted that there are some regional differences in threats for the
Hawaii DPS, but it was unable to identify portions of the DPS that both
faced particularly high threats and were so significant to the
viability of the DPS as a whole that, if lost, would result in the
remainder of the DPS being at high risk of extinction. The BRT noted
that there also are some regional differences in threats for the Mexico
DPS, and some evidence for minor substructure within the DPS due to
multiple breeding locations associated with somewhat distinctive
feeding grounds. However, the BRT was unable to identify portions of
the DPS that faced particularly high threats compared to other portions
of the DPS or that appeared to be at high risk of extirpation. We
agree, and we conclude that no portions of either DPS face particularly
high threats and are so significant to the viability of the DPS that,
if lost, the DPSs would be in danger of extinction, or likely to become
so in the foreseeable future. Therefore, we conclude that neither DPS
is in danger of extinction in a significant portion of its range, or
likely to become so in the foreseeable future.
We conclude that the Hawaii and Mexico DPSs are not endangered or
threatened throughout all or a significant portion of their ranges, and
we therefore do not propose to list the Hawaii and Mexico DPSs as a
threatened or endangered species.
In the Southern Hemisphere, all seven DPSs are thought to be
greater than 2,000 individuals in population size. The Brazil DPS is
increasing either rapidly or moderately. The trend of the Gabon/
Southwest Africa DPS is unknown. The trend of the Southeast Africa/
Madagascar DPS is thought to either be increasing or stable. The trend
of the Oceania DPS is unknown. The West Australia and East Australia
DPSs are both large and increasing rapidly. The Southeastern Pacific
DPS is thought to either be increasing or stable. In the Southern
Hemisphere, all threats are considered likely to have no or minor
impact on population size and/or the growth rate or are unknown, with
the exception of energy exploration posing a moderate threat to the
West Australia and Gabon/Southwest Africa DPSs, and fishing gear
entanglements posing a moderate threat to the Southeastern Pacific,
Southeast Africa/Madagascar, and Oceania DPSs. The BRT distributed at
least 93 percent of their likelihood points to the ``not at risk of
extinction'' category for six DPSs in the Southern Hemisphere (Brazil,
Gabon/Southwest Africa, and Southeast Africa/Madagascar, West
Australia, East Australia, and Southeastern Pacific DPSs), thus
indicating a high certainty in its voting. For the Oceania DPS, the BRT
distributed 68 percent of its points to the ``not at risk of
extinction'' category, indicating moderate certainty, and 29 percent of
its points to the ``moderate risk of extinction'' category, indicating
some support. None of the factors that may negatively impact the status
of the humpback whale appear to pose a threat to recovery, either alone
or cumulatively, for these DPSs. Given the large population sizes
(>2,000) for all seven DPSs, the fact that none of these DPSs is known
to be decreasing in population size and some are increasing, the high
percentage of (or, in the case of the Oceania DPS, the majority of)
likelihood points allocated to the ``not at risk of extinction''
category, and the high certainty associated with six of these
extinction risk estimates and moderate certainty associated with the
extinction risk estimate for the Oceania DPS, we conclude that none of
these seven DPSs are at risk of extinction throughout all of their
ranges now or in the foreseeable future.
Next, per the SPOIR Policy, we need to determine whether any of
these DPSs are in danger of extinction or likely to become so in the
foreseeable future in a significant portion of their ranges. The BRT
was unable to identify portions of the Brazil, Southeast Africa/
Madagascar, West Australia, East Australia, and Southeastern Pacific
DPSs that both faced particularly high threats and were so significant
to the viability of the DPSs as a whole that, if lost, would result in
the remainder of the DPSs being at high risk of extinction. We agree,
and we also conclude that no portions of these DPSs face particularly
high threats and are so significant to the viability of the DPSs that,
if lost, any DPS would be in danger of extinction, or likely to become
so in the foreseeable future. Therefore, we conclude that the Brazil,
Southeast Africa/Madagascar, West Australia, East Australia, and
Southeastern Pacific DPSs are not threatened or endangered in a
significant portion of their ranges.
The BRT concluded that there was some evidence for population
substructure within the Gabon/Southwest Africa DPS, based on an
extensive breeding range with some significant genetic differentiation
among breeding locations (Rosenbaum et al., 2009). However, the BRT was
unable to identify any portions of the DPS that both faced particularly
high threats and were so significant to the viability of the DPS as a
whole that, if lost, would result in the remainder of the DPS being at
high risk of extinction. We agree, and we also conclude that no
portions of this DPS face particularly high threats and are so
significant to the viability of the DPS that, if lost, the DPS would be
[[Page 22351]]
in danger of extinction, or likely to become so in the foreseeable
future. Therefore, we conclude that the Gabon/Southwest Africa DPS is
not threatened or endangered in a significant portion of its range.
The BRT noted that the Oceania DPS has potentially somewhat greater
substructure than most other humpback whale DPSs due to its extended
breeding range, though a lack of strong genetic structure indicates
there are likely to be considerable demographic connections among these
areas. Some threats, such as whale watching in the Southern Lagoon of
New Caledonia, appear to be localized. Nonetheless, the BRT was unable
to identify any specific areas where threats were sufficiently severe
to be likely to cause local extirpation. We agree, and we also conclude
that no portion of this DPS faces particularly high threats and is so
significant to the viability of the DPS that, if lost, the DPS would be
in danger of extinction, or likely to become so in the foreseeable
future. Therefore, we conclude that the Oceania DPS is not threatened
or endangered in a significant portion of its range.
We conclude that none of the seven DPSs in the Southern Hemisphere
are endangered or threatened throughout all or a significant portion of
their ranges, and we therefore do not propose to list the Brazil,
Gabon/Southwest Africa, Southeast Africa/Madagascar, West Australia,
East Australia, Oceania, and Southeastern Pacific DPSs as endangered or
threatened species.
Monitoring Plan
We will work with the states and countries within the range of the
ten DPSs that we do not propose for listing (which has the effect of
removing them from the endangered species list) to develop a plan for
continuing to monitor the status of these DPSs. The objective of the
monitoring plan will be to ensure that necessary recovery actions
remain in place and to ensure the absence of substantial new threats to
the DPSs' continued existence. In part such monitoring efforts are
already an integral component of ongoing research, existing stranding
networks, and other management and enforcement programs implemented
under the MMPA. These activities are conducted by NMFS in collaboration
with other Federal and state agencies, the Western Pacific Fishery
Management Council, North Pacific Fishery Management Council, the New
England Fishery Management Council, university affiliates, and private
research groups. As noted in Bettridge et al. (2015), many regulatory
avenues already in existence provide for review of proposed projects to
reduce or prevent adverse effects to humpback whales and for post-
project monitoring to ensure protection to humpback whales, as well as
penalties for violation of the prohibition on unauthorized take under
the MMPA for all DPSs that occur in U.S. waters or by U.S. persons or
vessels on the high seas. However, the addition and implementation of
specific Monitoring Plans will provide an additional degree of
attention and an early warning system to ensure that constructively
removing these ten DPSs from the endangered species list will not
result in the re-emergence of threats to the DPSs.
Description of Proposed Regulatory Changes
To implement this proposed action we propose to replace the
humpback whale listing on the endangered species list at 50 CFR 224.101
with the Cape Verde Islands/Northwest Africa and Arabian Sea DPSs of
the humpback whale and add the Western North Pacific and Central
America DPSs of the humpback whale to the list of threatened species at
50 CFR 223.102.
Prohibitions and Protective Measures
Section 9 of the ESA prohibits certain activities that directly or
indirectly affect endangered species. These prohibitions apply to all
individuals, organizations and agencies subject to U.S. jurisdiction.
Section 4(d) of the ESA directs the Secretary of Commerce (Secretary)
to implement regulations ``to provide for the conservation of
[threatened] species'' that may include extending any or all of the
prohibitions of section 9 to threatened species. Section 9(a)(1)(g)
also prohibits violations of protective regulations for threatened
species implemented under section 4(d). We are proposing to extend all
of the prohibitions of section 9(a)(1) in protective regulations issued
under the second sentence of section 4(d) for the Western North Pacific
and Central America DPSs of the humpback whale. No special findings are
required to support extending Section 9 prohibitions for the protection
of threatened species. See In re Polar Bear Endangered Species Act
Listing and 4(d) Rule Litigation, 818 F.Supp.2d 214, 228 (D.D.C. 2011);
Sweet Home Chapter of Cmties. for a Great Oregon v. Babbitt, 1 F.3d 1,
8 (D.C. Cir.1993), modified on other grounds on reh'g, 17 F.3d 1463
(D.C. Cir. 1994), rev'd on other grounds, 515 U.S. 687 (1995).
Sections 7(a)(2) and (4) of the ESA require Federal agencies to
consult or confer with us to ensure that activities they authorize,
fund, or conduct are not likely to jeopardize the continued existence
of a listed species or a species proposed for listing, or to adversely
modify critical habitat or proposed critical habitat. If a Federal
action may affect a listed species or its critical habitat, the
responsible Federal agency must enter into consultation with us.
Examples of Federal actions that may affect the Cape Verde Islands/
Northwest Africa, Western North Pacific, and Central America DPSs of
the humpback whale include permits and authorizations for shipping,
fisheries, oil and gas exploration, and toxic waste and other pollutant
discharges, if they occur in U.S. waters or the high seas.
Sections 10(a)(1)(A) and (B) of the ESA provide us with authority
to grant exceptions to the ESA's section 9 ``take'' prohibitions.
Section 10(a)(1)(A) scientific research and enhancement permits may be
issued to entities (Federal and non-Federal) for scientific purposes or
to enhance the propagation or survival of a listed species. The type of
activities potentially requiring a section 10(a)(1)(A) research/
enhancement permit include scientific research that targets humpback
whales, including the importation of non-U.S. samples for research
conducted in the United States. Section 10(a)(1)(B) incidental take
permits are required for non-Federal activities that may incidentally
take a listed species in the course of an otherwise lawful activity.
Identification of Those Activities That Would Constitute a Violation of
Section 9 of the ESA
On July 1, 1994, NMFS and the FWS issued an Interagency Cooperative
Policy for Endangered Species Act Section 9 Prohibitions (59 FR 34272).
The intent of this policy is to increase public awareness of the effect
of our ESA listing on proposed and ongoing activities within the
species' range. We will identify, to the extent known at the time of
the final rule, specific activities that will be considered likely to
result in violation of section 9, as well as activities that will not
be considered likely to result in violation. Because the Cape Verde
Islands/Northwest Africa and Arabian Sea DPSs occur outside of the
jurisdiction of the United States, we are presently unaware of any
activities that could result in violation of section 9 of the ESA for
these DPSs; nevertheless, the possibility for violations exists (for
example, import into the United States). Activities that we believe
could result in violation of section 9 prohibitions against ``take'' of
the Western North Pacific and Central America DPSs of the humpback
whale include: (1) Unauthorized harvest or
[[Page 22352]]
lethal takes of humpback whales in the Western North Pacific and
Central America DPSs by U.S. citizens; (2) in-water activities
conducted by U.S. citizens that produce high levels of underwater
noise, which may harass or injure humpback whales in the Western North
Pacific and Central America DPSs; (3) U.S. fisheries that may result in
entanglement of humpback whales in the Western North Pacific and
Central America DPSs; (4) vessel strikes from U.S. ships operating in
U.S. waters or on the high seas; and (5) discharging or dumping toxic
chemicals or other pollutants by U.S. citizens into areas used by
humpback whales from the Western North Pacific and Central America
DPSs.
We expect, based on the best available information, the following
actions will not result in a violation of section 9: (1) Federally
funded or approved projects for which ESA section 7 consultation has
been completed and necessary mitigation developed, and that are
conducted in accordance with any terms and conditions we provide in an
incidental take statement accompanying a biological opinion; and (2)
takes of humpback whales in the Western North Pacific and Central
America DPSs that have been authorized by NMFS pursuant to section 10
of the ESA. These lists are not exhaustive. They are intended to
provide some examples of the types of activities that we might or might
not consider as constituting a take of humpback whales in the Western
North Pacific and Central America DPSs.
Effects of This Rulemaking
Conservation measures provided for species listed as endangered or
threatened under the ESA include recovery actions (16 U.S.C. 1533(f));
concurrent designation of critical habitat, if prudent and determinable
(16 U.S.C. 1533(a)(3)(A)); Federal agency requirements to consult with
NMFS under section 7 of the ESA to ensure their actions do not
jeopardize the species or result in adverse modification or destruction
of critical habitat should it be designated (16 U.S.C. 1536); and
prohibitions on taking (16 U.S.C. 1538). Recognition of the species'
plight through listing promotes conservation actions by Federal and
state agencies, foreign entities, private groups, and individuals. The
main effects of the proposed listings are prohibitions on take,
including export and import. If this proposed rule is finalized, the
provisions discussed above will no longer apply to the DPSs that are in
effect removed from the endangered species list.
The MMPA provides substantial protections to all marine mammals,
such as humpback whales, whether they are listed under the ESA or not.
In addition, the MMPA provides heightened protections to marine mammals
designated as ``depleted'' (e.g., no take waiver, additional
restrictions on the issuance of permits for research, importation, and
captive maintenance), including humpback whales. Section 3(1) of the
MMPA defines ``depleted'' as ``any case in which'': (1) The Secretary
``determines that a species or population stock is below its optimum
sustainable population''; (2) a state to which authority has been
delegated makes the same determination; or (3) a species or stock ``is
listed as an endangered species or a threatened species under the
[ESA]'' (16 U.S.C. 1362(1)). Section 115(a)(1) of the MMPA establishes
that ``[i]n any action by the Secretary to determine if a species or
stock should be designated as depleted, or should no longer be
designated as depleted,'' such determination must be made by rule,
after public notice and an opportunity for comment (16 U.S.C.
1383b(a)(1)). It is NMFS' position that a marine mammal species
automatically gains ``depleted'' status under the MMPA when it is
listed under the ESA. In the absence of an ESA listing, NMFS follows
the procedures described in section 115(a)(1) to designate a marine
mammal species as depleted when the basis for its depleted status is
that it is below its optimum sustainable population. This
interpretation was recently confirmed by the United States Court of
Appeals for the D.C. Circuit. See In re Polar Bear Endangered Species
Act Listing and Section 4(d) Rule Litigation, 720 F.3d 354 (D.C. Cir.
2013). Humpback whales are currently designated as ``depleted'' under
the MMPA because of the species' ESA listing. NMFS has not separately
determined that the humpback whale species is depleted on the basis
that it is below its optimum sustainable population.
NMFS is currently evaluating what result sections 3(1) and
115(a)(1) of the MMPA require when a species that holds depleted status
solely because of its ESA listing is found to no longer warrant ESA
listing. Thus, we are currently reviewing whether any DPS of the
humpback whale that is not listed under the ESA after a final rule is
published would automatically lose depleted status under the MMPA, or
whether the agency must undertake additional analysis and complete
additional procedures before a change in depleted status may occur. We
seek comments from the public regarding different options for
construing the relevant provisions of these statutes in harmony and
will consider all viable alternatives (see ADDRESSES).
This rule also has implications for the approach regulations
currently at 50 CFR 224.103(a) and (b), discussed previously. With
regard to the regulations in effect in Hawaii (224.103(a)), the
delisting of the Hawaii DPS, if finalized, would remove the ESA basis
for promulgation of that rule. However, the substantially similar
protections in effect within the Hawaiian Islands Humpback Whale
National Marine Sanctuary, at 15 CFR 922.184, may provide sufficient
protection for the species. We note that the Office of National Marine
Sanctuaries has recently proposed to, among other things, expand the
sanctuary boundaries and strengthen the protections from approaching
vessels (80 FR 16224, 16238; March 26, 2015). We plan to propose,
through separate rulemaking, to remove the approach regulations at
Sec. 224.103(a) because those regulations are specific to endangered
species. If additional protection is determined necessary, we may
undertake separate rulemaking pursuant to the MMPA. We request public
comment on this issue.
With regard to the regulations in effect in Alaska (224.103(b)),
the impacts of this proposed rule are different. When the Alaska
provisions were adopted, we cited Section 112(a) of the MMPA in
addition to Section 11(f) of the ESA as authority (16 U.S.C. 1382(a);
16 U.S.C. 1540(f)). However, because the humpback whale was listed
throughout its range as endangered, the rule was codified only in Part
224 of the ESA regulations (which applies to ``Endangered Marine and
Anadromous Species''). The reclassification of the Western North
Pacific DPS to threatened, if finalized, would require relocating the
provisions from Part 224 to Part 223 (which applies to ``Threatened
Marine and Anadromous Species''). By separate rulemaking, we plan to
propose to relocate these provisions to a new section, 223.214 in order
to continue the protection of the threatened humpback whales in Alaska,
because these provisions have been in effect for 14 years and are
important in light of the potential impacts posed by the whalewatching
industry, recreational boating community, and other maritime users. We
would simultaneously delete current 50 CFR 224.103(b). In the separate
rulemaking, we also plan to propose to set out these provisions in Part
216 of Title 50 of the
[[Page 22353]]
Code of Federal Regulations for the protection of all humpback whales
that may occur or transit through the waters surrounding Alaska, to
reflect that these provisions were adopted under the MMPA as well as
the ESA and are an important source of protection for these marine
mammals. We seek public comment on this issue as well.
Peer Review
In December 2004, the Office of Management and Budget (OMB) issued
a Final Information Quality Bulletin for Peer Review establishing a
minimum peer review standard. The intent of the peer review policies is
to ensure that listings are based on the best scientific and commercial
data available. The BRT enlisted the help of the Marine Mammal
Commission (MMC) to coordinate scientific peer review of the June 2012
draft of its status review report. The MMC received comments from five
reviewers and these reviews were provided, without attribution, to the
BRT. The BRT addressed all peer review comments in the final status
review report (Bettridge et al., 2015) being released with the
publication of this 12-month finding/proposed rule. We conclude that
these experts' reviews satisfy the requirements for ``adequate [prior]
peer review'' contained in the Bulletin (sec. II.2.).
Critical Habitat
Section 3 of the ESA (16 U.S.C. 1532(5A)) defines critical habitat
as ``(i) the specific areas within the geographical area occupied by
the species, at the time it is listed . . . on which are found those
physical or biological features (I) essential to the conservation of
the species and (II) which may require special management
considerations or protection; and (ii) specific areas outside the
geographical area occupied by the species at the time it is listed . .
. upon a determination by the Secretary that such areas are essential
for the conservation of the species.'' Section 3 of the ESA also
defines the terms ``conserve,'' ``conserving,'' and ``conservation'' to
mean ``to use and the use of all methods and procedures which are
necessary to bring any endangered species or threatened species to the
point at which the measures provided pursuant to this chapter are no
longer necessary'' (16 U.S.C. 1532(3)).
Section 4(a)(3)(A)(i) of the ESA requires that, to the maximum
extent practicable and determinable, critical habitat be designated
concurrently with the listing of a species. Designation of critical
habitat must be based on the best scientific data available, and must
take into consideration the economic, national security, and other
relevant impacts of specifying any particular area as critical habitat
(16 U.S.C. 1533(b)(2)). Once critical habitat is designated, section 7
of the ESA requires Federal agencies to ensure that they do not fund,
authorize, or carry out any actions that are likely to destroy or
adversely modify that habitat (16 U.S.C. 1536(a)(2)). This requirement
is in addition to the section 7 requirement that Federal agencies
ensure their actions do not jeopardize the continued existence of the
species.
In determining what areas qualify as critical habitat, 50 CFR
424.12(b) requires that NMFS ``consider those physical or biological
features that are essential to the conservation of a given species
including space for individual and population growth and for normal
behavior; food, water, air, light, minerals, or other nutritional or
physiological requirements; cover or shelter; sites for breeding,
reproduction, and rearing of offspring; and habitats that are protected
from disturbance or are representative of the historical geographical
and ecological distribution of a species.'' The regulations further
direct NMFS to ``focus on the principal biological or physical
constituent elements . . . that are essential to the conservation of
the species,'' and specify that the ``known primary constituent
elements shall be listed with the critical habitat description.'' The
regulations identify primary constituent elements (PCEs) as including,
but not limited to: ``roost sites, nesting grounds, spawning sites,
feeding sites, seasonal wetland or dryland, water quality or quantity,
host species or plant pollinator, geological formation, vegetation
type, tide, and specific soil types.''
The ESA directs the Secretary of Commerce to consider the economic
impact, the national security impacts, and any other relevant impacts
from designating critical habitat, and under section 4(b)(2), the
Secretary may exclude any area from such designation if the benefits of
exclusion outweigh those of inclusion, provided that the exclusion will
not result in the extinction of the species. At this time, critical
habitat for the humpback whales in the Western North Pacific and
Central America DPSs is not determinable. We will propose critical
habitat for the Western North Pacific and Central America DPSs of the
humpback whale in a separate rulemaking if we determine that it is
prudent to do so. To assist us with that rulemaking, we specifically
request information to help us identify the essential features of this
habitat, and to what extent those features may require special
management considerations or protection, as well as the economic
activities within the range of the Western North Pacific and Central
America DPSs that could be impacted by critical habitat designation. 50
CFR 424.12(h) specifies that critical habitat shall not be designated
within foreign countries or in other areas outside U.S. jurisdiction.
Therefore, we request information only on potential areas of critical
habitat within the United States or waters within U.S. jurisdiction.
Because the known distribution of the humpback whales in the Cape
Verde Islands/Northwest Africa and Arabian Sea DPSs occurs in areas
outside the jurisdiction of the United States, no critical habitat will
be designated for these DPSs.
Public Comments Solicited
Relying on the best scientific and commercial information
available, we exercised our best professional judgment in developing
this proposal to divide the humpback whale into 14 DPSs, retain the
Cape Verde Islands/Northwest Africa and Arabian Sea DPSs on the list of
endangered species at 50 CFR 224.101, add the Western North Pacific and
Central America DPSs to the list of threatened species and extend all
section 9 prohibitions to these DPSs, and remove the other 10 DPSs
(West Indies, Hawaii, Mexico, Brazil, Gabon/Southwest Africa, Southeast
Africa/Madagascar, West Australia, East Australia, Oceania, and
Southeastern Pacific) from the endangered species list at 50 CFR
224.101. To ensure that the final action resulting from this proposal
will be as accurate and effective as possible, we solicit comments and
suggestions concerning this proposed rule from the public, other
concerned governments and agencies, Indian tribal governments, Alaska
Native tribal governments or organizations, the scientific community,
industry, and any other interested parties. Comments are encouraged on
this proposal as well as on the status review report (See DATES and
ADDRESSES). Comments are particularly sought concerning:
(1) The identification of 3 subspecies of humpback whale comprised
of 14 DPSs;
(2) The current population status of identified humpback whale
DPSs;
(3) Biological or other information regarding the threats to the
identified humpback whale DPSs;
(4) Information on the effectiveness of ongoing and planned
humpback whale conservation efforts by countries, states, or local
entities;
[[Page 22354]]
(5) Activities that could result in a violation of section 9(a)(1)
of the ESA if such prohibitions are applied to the Western North
Pacific and Central America DPSs;
(6) Whether any DPS of the humpback whale that is not listed under
the ESA in a final rule would automatically lose depleted status under
the MMPA, or, if not, what analysis and process is required by the MMPA
before a change in depleted status may occur. We seek comments
regarding different options for construing the relevant provisions of
these statutes in harmony;
(7) Whether approach regulations should be promulgated under the
MMPA for the protection of the Hawaii DPS of the humpback whale, since
if this rule becomes final, that DPS will no longer be listed under the
ESA, or whether current protections in effect in the Hawaiian Islands
Humpback Whale National Marine Sanctuary (at 15 CFR 922.184) are
sufficient for the protection of the species from vessel interactions.
Commenters should consider the impact of the recent proposal by NOAA's
Office of National Marine Sanctuaries to expand the sanctuary
boundaries and strengthen the approach regulations (80 FR 16224; March
26, 2015);
(8) Whether approach regulations in effect for the protection of
humpback whales in Alaska, currently set forth at 50 CFR 224.103(b),
should be relocated to Part 223 (which applies to threatened species)
for the continuing protection of the Western North Pacific DPS, and
whether these regulations should also be set out in 50 CFR 216 as MMPA
regulations for the protection of all humpback whales occurring in that
area in light of the fact that the MMPA was one of the original
authorities cited in promulgating the regulation;
(9) Information related to the designation of critical habitat,
including identification of those physical or biological features which
are essential to the conservation of the Western North Pacific and
Central America DPSs of humpback whale and which may require special
management consideration or protection;
(10) Economic, national security, and other relevant impacts from
the designation of critical habitat for the Western North Pacific and
Central America DPSs of humpback whale; and
(11) Research and other activities that would be important to
include in post-delisting monitoring plans for the West Indies, Hawaii,
Mexico, Brazil, Gabon/Southwest Africa, Southeast Africa/Madagascar,
West Australia, East Australia, Oceania, and Southeastern Pacific DPSs.
You may submit your comments and materials concerning this proposal
by any one of several methods (see ADDRESSES). We will review all
public comments and any additional information regarding the status of
the identified DPSs of the humpback whale and will complete a final
determination within 1 year of publication of this proposed rule, as
required under the ESA. Final promulgation of the regulation(s) will
consider the comments and any additional information we receive, and
such communications may lead to a final regulation that differs from
this proposal.
Public Hearings
During each public hearing, a brief opening presentation on the
proposed rule will be provided before accepting public testimony.
Written comments may be submitted at the hearing or via the Federal e-
Rulemaking Portal (see ADDRESSES) until the scheduled close of the
comment period on July 20, 2015. In the event that attendance at the
public hearings is large, the time allotted for oral statements may be
limited. Oral and written statements receive equal consideration. There
are no limits on the length of written comments submitted to us.
Public Hearing Schedule
The dates and locations for the four hearings are as follows:
1. Honolulu: May 6, 2015, from 6:00 p.m. to 8:00 p.m. at the
Japanese Cultural Center, Manoa Ballroom, 2454 South Beretania
Street, Honolulu, HI 96826, with an informational open house
beginning at 5:30 p.m. Parking is available at the Japanese Cultural
Center for $5.
2. Juneau: May 19, 2015, 5 p.m. to 8 p.m. at the Centennial
Hall, Hickel Room, 101 Egan Drive, Juneau, AK.
3. Plymouth: June 3, 2015, 6 p.m. to 8:30 p.m., Plymouth Public
Library, 132 South Street, Plymouth, MA.
4. Virginia Beach: June 9, 2015, 5 p.m. to 6:30 p.m., at the
Hilton Virgina Beach Oceanfront, 3001 Atlantic Ave, Virginia Beach,
VA. This will be in conjunction with the Mid-Atlantic Fishery
Management Council's meeting being held during the same week.
Special Accommodations
These hearings are physically accessible to people with
disabilities. Requests for sign language interpretation or other
accommodations should be directed to Marta Nammack (see ADDRESSES) as
soon as possible, but no later than 7 business days prior to the
hearing date.
Classification
National Environmental Policy Act (NEPA)
The 1982 amendments to the ESA, in section 4(b)(1)(A), restrict the
information that may be considered when assessing species for listing.
Based on this limitation of criteria for a listing decision and the
opinion in Pacific Legal Foundation v. Andrus, 657 F. 2d 829 (6th Cir.
1981), we have concluded that NEPA does not apply to ESA listing
actions. (See NOAA Administrative Order 216-6.) We are currently
reviewing whether any other aspect of this proposed rule will require
NEPA analysis.
Executive Order (E.O.) 12866, Paperwork Reduction Act, and Regulatory
Flexibility Act
This rule is exempt from review under E.O. 12866. This proposed
rule does not contain a collection of information requirement for the
purposes of the Paperwork Reduction Act.
As noted in the Conference Report on the 1982 amendments to the
ESA, economic impacts cannot be considered when assessing the status of
a species. Therefore, the economic analyses required by the Regulatory
Flexibility Act are not applicable to the listing process.
E.O. 13132, Federalism
E.O. 13132 requires agencies to take into account any federalism
impacts of regulations under development. It includes specific
directives for consultation in situations where a regulation will
preempt state law or impose substantial direct compliance costs on
state and local governments (unless required by statute). Neither of
those circumstances is applicable to this proposed rule; therefore this
action does not have federalism implications as that term is defined in
E.O. 13132.
E.O. 13175, Consultation and Coordination With Indian Tribal
Governments
The longstanding and distinctive relationship between the Federal
and tribal governments is defined by treaties, statutes, executive
orders, judicial decisions, and co-management agreements, which
differentiate tribal governments from the other entities that deal
with, or are affected by, the Federal government. This relationship has
given rise to a special Federal trust responsibility involving the
legal responsibilities and obligations of the United States toward
Indian Tribes and the application of fiduciary standards of
[[Page 22355]]
due care with respect to Indian lands, tribal trust resources, and the
exercise of tribal rights. E.O. 13175--Consultation and Coordination
with Indian Tribal Governments--outlines the responsibilities of the
Federal Government in matters affecting tribal interests. Section 161
of Public Law 108-199 (188 Stat. 452), as amended by section 518 of
Public Law 108-447 (118 Stat. 3267), directs all Federal agencies to
consult with Alaska Native tribes or organizations on the same basis as
Indian tribes under E.O. 13175.
We intend to coordinate with tribal governments and native
corporations which may be affected by the proposed action. We will
provide them with a copy of this proposed rule for review and comment,
and offer the opportunity to consult on the proposed action.
List of Subjects
50 CFR Part 223
Endangered and threatened species, Exports, Imports,
Transportation.
50 CFR Part 224
Endangered and threatened species.
Dated: April 15, 2015.
Samuel D. Rauch, III,
Deputy Assistant Administrator for Regulatory Programs, National Marine
Fisheries Service.
For the reasons set out in the preamble, 50 CFR parts 223 and 224
are proposed to be amended as follows:
PART 223--THREATENED MARINE AND ANADROMOUS SPECIES
0
1. The authority citation for part 223 continues to read as follows:
Authority: 16 U.S.C. 1531 1543; subpart B, Sec. 223.201-202
also issued under 16 U.S.C. 1361 et seq.; 16 U.S.C. 5503(d) for
Sec. 223.206(d)(9).
0
2. In Sec. 223.102, in paragraph (e), the table is amended by adding
entries for ``Whale, humpback (Central America DPS)'' and ``Whale,
humpback (Western North Pacific DPS)'' under MARINE MAMMALS in
alphabetical order by Common Name to read as follows:
Sec. 223.102 Enumeration of threatened marine and anadromous species.
* * * * *
(e) * * *
----------------------------------------------------------------------------------------------------------------
Species \1\
--------------------------------------------------------------------- Citation(s) for Critical
Description of listing habitat ESA Rules
Common name Scientific name listed entity determination(s)
----------------------------------------------------------------------------------------------------------------
Marine Mammals
----------------------------------------------------------------------------------------------------------------
* * * * * * *
Whale, humpback (Central Megaptera Humpback whales that [Insert Federal NA 223.213
America DPS). novaeangliae. breed along the Register page
Pacific coast of where the
Costa Rica, Panama, document
Guatemala, El begins], April
Salvador, Honduras, 21, 2015.
and Nicaragua in
the eastern North
Pacific Ocean or
feed almost
exclusively
offshore of
California and
Oregon in the
eastern North
Pacific Ocean, with
some feeding off
northern Washington/
southern British
Columbia.
Whale, humpback (Western Megaptera Humpback whales that [Insert Federal NA 223.213
North Pacific DPS). novaeangliae. breed or winter in Register page 223.214
the area of Okinawa where the
and the Philippines document
in the Kuroshio begins], April
Current (as well as 21, 2015.
unknown breeding
grounds in the
Western North
Pacific Ocean),
transitthe
Ogasawara area, or
feed in the North
Pacific Ocean,
primarily in the
West Bering Sea and
off the Russian
coast and the
Aleutian Islands.
* * * * * * *
----------------------------------------------------------------------------------------------------------------
\1\ Species includes taxonomic species, subspecies, distinct population segments (DPSs) (for a policy statement,
see 61 FR 4722, February 7, 1996), and evolutionarily significant units (ESUs) (for a policy statement, see 56
FR 58612, November 20, 1991).
\2\ Jurisdiction for sea turtles by the Department of Commerce, National Oceanic and Atmospheric Administration,
National Marine Fisheries Service, is limited to turtles while in the water.
0
3. Add Sec. 223.213 to subpart B to read as follows:
Sec. 223.213 Western North Pacific and Central America distinct
population segments (DPSs) of the humpback whale.
Prohibitions. The prohibitions of section 9(a)(1)(A) through
9(a)(1)(G) of the ESA (16 U.S.C. 1538) relating to endangered species
shall apply to the Western North Pacific DPS and the Central America
DPS of the humpback whale listed in Sec. 223.102(e).
PART 224--ENDANGERED MARINE AND ANADROMOUS SPECIES
0
4. The authority citation for part 224 continues to read as follows:
Authority: 16 U.S.C. 1531-1543 and 16 U.S.C. 1361 et seq.
0
5. In Sec. 224.101, in the table in paragraph (h), revise the entry
for ``Whale, humpback'' to read as follows:
Sec. 224.101 Enumeration of endangered marine and anadromous species.
* * * * *
(h) * * *
[[Page 22356]]
----------------------------------------------------------------------------------------------------------------
Species \1\
--------------------------------------------------------------------- Citation(s) for Critical
Description of listing habitat ESA rules
Common name Scientific name listed entity determination(s)
----------------------------------------------------------------------------------------------------------------
Marine Mammals
----------------------------------------------------------------------------------------------------------------
* * * * * * *
Whale, humpback (Arabian Sea Megaptera Humpback whales that [Insert Federal NA NA
DPS). novaeangliae. breed or feed in Register page
the Arabian Sea. where the
document
begins], April
21, 2015.
Whale, humpback whale (Cape Megaptera Humpback whales that [Insert Federal NA NA
Verde Islands/Northwest novaeangliae. breed in waters Register page
Africa DPS). surrounding the where the
Cape Verde Islands document
in the Eastern begins], April
North Atlantic 21, 2015.
Ocean, as well as
an undetermined
breeding area in
the eastern
tropical Atlantic
(possibly Canary
Current) or feed
along the Iceland
Shelf and Sea and
the Norwegian Sea.
* * * * * * *
----------------------------------------------------------------------------------------------------------------
\1\ Species includes taxonomic species, subspecies, distinct population segments (DPSs) (for a policy statement,
see 61 FR 4722, February 7, 1996), and evolutionarily significant units (ESUs) (for a policy statement, see 56
FR 58612, November 20, 1991).
\2\ Jurisdiction for sea turtles by the Department of Commerce, National Oceanic and Atmospheric Administration,
National Marine Fisheries Service, is limited to turtles while in the water.
[FR Doc. 2015-09010 Filed 4-20-15; 8:45 am]
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