[Federal Register: December 18, 2008 (Volume 73, Number 244)]
[Proposed Rules]
[Page 77263-77302]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18de08-35]
[[Page 77263]]
-----------------------------------------------------------------------
Part III
Department of the Interior
-----------------------------------------------------------------------
Fish and Wildlife Service
-----------------------------------------------------------------------
50 CFR Part 17
Endangered and Threatened Wildlife and Plants; 12-Month Findings on
Petitions To List Penguin Species as Threatened or Endangered Under the
Endangered Species Act; Proposed Rules
[[Page 77264]]
-----------------------------------------------------------------------
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[FWS-R9-IA-2008-0069; 96000-1671-0000-B6]
RIN 1018-AV73
Endangered and Threatened Wildlife and Plants; 12-Month Finding
on a Petition To List Four Penguin Species as Threatened or Endangered
Under the Endangered Species Act and Proposed Rule To List the Southern
Rockhopper Penguin in the Campbell Plateau Portion of Its Range
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule and notice of 12-month petition finding.
-----------------------------------------------------------------------
SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a
12-month finding on a petition to list four species of penguins as
threatened or endangered under the Endangered Species Act of 1973, as
amended (Act). After a thorough review of all available scientific and
commercial information, we find that the petitioned action for the
Campbell Plateau portion of the range of the New Zealand/Australia
Distinct Population Segment (DPS) of the southern rockhopper penguin
(Eudyptes chrysocome) is warranted, and we propose to list this species
as threatened under the Act in the Campbell Plateau portion of its
range. This proposal, if made final, would extend the Act's protection
to this species in that portion of its range. In addition, we find that
listing under the Act is not warranted for the remainder of the range
of the southern rockhopper penguin and throughout all or any portion of
the range for the northern rockhopper penguin (Eudyptes moseleyi),
macaroni penguin (Eudyptes chrysolophus), and emperor penguin
(Aptenodytes forsteri).
DATES: We made the finding announced in this document on December 18,
2008. We will accept comments and information on the proposed rule
received or postmarked on or before February 17, 2009. We must receive
requests for public hearings on the proposed rule, in writing, at the
address shown in the FOR FURTHER INFORMATION CONTACT section by
February 2, 2009.
ADDRESSES: Comments on Proposed Rule: If you wish to comment on the
proposed rule to list the southern rockhopper penguin in the Campbell
Plateau portion of its range, you may submit comments by one of the
following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the instructions for submitting comments.
U.S. mail or hand-delivery: Public Comments Processing,
Attn: [FWS-R9-IA-2008-0069]; Division of Policy and Directives
Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive,
Suite 222; Arlington, VA 22203.
We will not accept comments by e-mail or fax. We will post all
comments on http://www.regulations.gov. This generally means that we
will post any personal information you provide us (see the Public
Comments Solicited section below for more information).
Supporting Documents for 12-Month Finding: Supporting documentation
we used in preparing this finding is available for public inspection,
by appointment, during normal business hours at the U.S. Fish and
Wildlife Service, Division of Scientific Authority, 4401 N. Fairfax
Drive, Room 110, Arlington, VA 22203; telephone 703-358-1708; facsimile
703-358-2276. Please submit any new information, materials, comments,
or questions concerning this finding to the above address.
FOR FURTHER INFORMATION CONTACT: Pamela Hall, Branch Chief, Division of
Scientific Authority, U.S. Fish and Wildlife Service, 4401 N. Fairfax
Drive, Room 110, Arlington, VA 22203; telephone 703-358-1708; facsimile
703-358-2276. If you use a telecommunications device for the deaf
(TDD), call the Federal Information Relay Service (FIRS) at 800-877-
8339.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(A) of the Act (16 U.S.C. 1533(b)(3)(A)) requires
the Service to make a finding known as a ``90-day finding,'' on whether
a petition to add, remove, or reclassify a species from the list of
endangered or threatened species has presented substantial information
indicating that the requested action may be warranted. To the maximum
extent practicable, the finding shall be made within 90 days following
receipt of the petition and published promptly in the Federal Register.
If the Service finds that the petition has presented substantial
information indicating that the requested action may be warranted
(referred to as a positive finding), section 4(b)(3)(A) of the Act
requires the Service to commence a status review of the species if one
has not already been initiated under the Service's internal candidate
assessment process. In addition, section 4(b)(3)(B) of the Act requires
the Service to make a finding within 12 months following receipt of the
petition on whether the requested action is warranted, not warranted,
or warranted but precluded by higher-priority listing actions (this
finding is referred to as the ``12-month finding''). Section 4(b)(3)(C)
of the Act requires that a finding of warranted but precluded for
petitioned species should be treated as having been resubmitted on the
date of the warranted but precluded finding, and is, therefore, subject
to a new finding within 1 year and subsequently thereafter until we
take action on a proposal to list or withdraw our original finding. The
Service publishes an annual notice of resubmitted petition findings
(annual notice) for all foreign species for which listings were
previously found to be warranted but precluded.
In this notice, we announce a 12-month finding on the petition to
list four penguins: southern rockhopper penguin, northern rockhopper
penguin, macaroni penguin, and emperor penguin. We will announce the
12-month findings for the African penguin (Spheniscus demersus),
yellow-eyed penguin (Megadyptes antipodes), white-flippered penguin
(Eudyptula minor albosignata), Fiordland crested penguin (Eudyptes
pachyrhynchus), Humboldt penguin (Spheniscus humboldti), and erect-
crested penguin (Eudyptes sclateri) in one or more separate Federal
Register notice(s).
Previous Federal Actions
On November 29, 2006, the Service received a petition from the
Center for Biological Diversity to list 12 penguin species under the
Act: Emperor penguin, southern rockhopper penguin, northern rockhopper
penguin, Fiordland crested penguin, snares crested penguin (Eudyptes
robustus), erect-crested penguin, macaroni penguin, royal penguin
(Eudyptes schlegeli), white-flippered penguin, yellow-eyed penguin,
African penguin, and Humboldt penguin. Among them, the ranges of the 12
penguin species include Antarctica, Argentina, Australian Territory
Islands, Chile, French Territory Islands, Namibia, New Zealand, Peru,
South Africa, and United Kingdom Territory Islands. The petition is
clearly identified as such, and contains detailed information on the
natural history, biology, status, and distribution of each of the 12
species. It also contains information on what the petitioner reported
as potential threats to the species from climate change and changes to
the marine environment, commercial fishing activities, contaminants and
pollution, guano extraction, habitat loss, hunting,
[[Page 77265]]
nonnative predator species, and other factors. The petition also
discusses existing regulatory mechanisms and the perceived inadequacies
to protect these species.
In the Federal Register of July 11, 2007 (72 FR 37695), we
published a 90-day finding in which we determined that the petition
presented substantial scientific or commercial information to indicate
that listing 10 species of penguins as endangered or threatened may be
warranted: Emperor penguin, southern rockhopper penguin, northern
rockhopper penguin, Fiordland crested penguin, erect-crested penguin,
macaroni penguin, white-flippered penguin, yellow-eyed penguin, African
penguin, and Humboldt penguin. Furthermore, we determined that the
petition did not provide substantial scientific or commercial
information indicating that listing the snares crested penguin and the
royal penguin as threatened or endangered species may be warranted.
Following the publication of our 90-day finding on this petition,
we initiated a status review to determine if listing each of the 10
species is warranted, and opened a 60-day public comment period to
allow all interested parties an opportunity to provide information on
the status of the 10 species of penguins. The public comment period
closed on September 10, 2007. In addition, we attended the
International Penguin Conference in Hobart, Tasmania, Australia, a
quadrennial meeting of penguin scientists from September 3-7, 2007
(during the open public comment period), to gather information and to
ensure that experts were aware of the status review and the open
comment period. We also consulted with other agencies and range
countries in an effort to gather the best available scientific and
commercial information on these species.
During the public comment period, we received over 4,450
submissions from the public, concerned governmental agencies, the
scientific community, industry, and other interested parties.
Approximately 4,324 e-mails and 31 letters received by U.S. mail or
facsimile were part of one letter-writing campaign and were
substantively identical. Each letter supported listing under the Act,
included a statement identifying ``the threat to penguins from global
warming, industrial fishing, oil spills and other factors,'' and listed
the 10 species included in the Service's 90-day finding. A further
group of 73 letters included the same information plus information
concerning the impact of ``abnormally warm ocean temperatures and
diminished sea ice'' on penguin food availability and stated that this
has led to population declines in southern rockhopper, Humboldt,
African, and emperor penguins. These letters stated that the emperor
penguin colony at Point Geologie has declined more than 50 percent due
to global warming and provided information on krill declines in large
areas of the Southern Ocean. They stated that continued warming over
the coming decades will dramatically affect Antarctica, the sub-
Antarctic islands, the Southern Ocean and the penguins dependent on
these ecosystems for survival. A small number of general letters and e-
mails drew particular attention to the conservation status of the
southern rockhopper penguin in the Falkland Islands.
Twenty submissions provided detailed, substantive information on
one or more of the 10 species. These included information from the
governments, or government-affiliated scientists, of Argentina,
Australia, Namibia, New Zealand, Peru, South Africa, and the United
Kingdom, from scientists, from 18 members of the U.S. Congress, and
from one non-governmental organization (the original petitioner).
On December 3, 2007, the Service received a 60-day Notice of Intent
To Sue from the Center for Biological Diversity (CBD). CBD filed a
complaint against the Department of the Interior on February 27, 2008,
for failure to make a 12-month finding on the petition. On September 8,
2008, the Service entered into a Settlement Agreement with CBD, in
which we agreed to submit to the Federal Register 12-month findings for
the 10 species of penguins, including the five penguin taxa that are
the subject of this proposed rule, on or before December 19, 2008.
We base our findings on a review of the best scientific and
commercial information available, including all information received
during the public comment period. Under section 4(b)(3)(B) of the Act,
we are required to make a finding as to whether listing each of the 10
species of penguins is warranted, not warranted, or warranted but
precluded by higher priority listing actions.
Introduction
In this notice, for each of the four species addressed, we first
provide background information on the biology of the species. Next, we
address each of the categories of factors listed in section 4(a)(1) of
the Act. For each factor, we first determine whether any stressors
appear to be causing declines in numbers of the species at issue
anywhere within the species' range. If we determine they are, then we
evaluate whether these stressors are causing population-level declines
that are significant to the determination of the conservation status of
the species. If so, we describe it as a ``threat.'' In the subsequent
finding section, we then consider each of the stressors and threats,
individually and cumulatively, and make a determination with respect to
whether the species is endangered or threatened according to the
statutory standard.
The term ``threatened species'' means any species (or subspecies
or, for vertebrates, distinct population segments) that is likely to
become an endangered species within the foreseeable future throughout
all or a significant portion of its range. The Act does not define the
term ``foreseeable future.'' For the purpose of this notice, we define
the ``foreseeable future'' to be the extent to which, given the amount
and substance of available data, we can anticipate events or effects,
or reliably extrapolate threat trends, such that we reasonably believe
that reliable predictions can be made concerning the future as it
relates to the status of the species at issue.
Species Information and Factors Affecting the Species
Section 4 of the Act (16 U.S.C. 1533), and its implementing
regulations at 50 CFR part 424, set forth the procedures for adding
species to the Federal Lists of Endangered and Threatened Wildlife and
Plants. A species may be determined to be an endangered or threatened
species due to one or more of the five factors described in section
4(a)(1) of the Act. The five factors are: (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; and (E) other natural or manmade
factors affecting its continued existence.
Southern Rockhopper Penguin and Northern Rockhopper Penguins
Taxonomy
Rockhopper penguins are among the smallest of the world's penguins,
averaging 20 inches (in) (52 centimeters (cm)) in length and 6.6 pounds
(lbs) (3 kilograms (kg)) in weight. They are the most widespread of the
crested penguins (genus Eudyptes), and are so named because of the way
they hop from boulder to boulder when moving
[[Page 77266]]
around their rocky colonies. Rockhopper penguins are found on islands
from near the Antarctic Polar Front to near the Subtropical Convergence
in the South Atlantic and Indian Oceans (Marchant and Higgins 1990, p.
183).
The taxonomy of the rockhopper complex is contentious. Formerly
treated as three subspecies (Marchant and Higgins 1990, p. 182), recent
papers suggested that these should be treated as two species (Jouventin
et al. 2006, pp. 3,413-3,423) or three species (Banks et al. 2006, pp.
61-67).
Jouventin et al. (2006, pp. 3,413-3,423), following up on recorded
differences in breeding phenology, song characteristics, and head
ornaments used as mating signals, conducted genetic analysis between
northern subtropical rockhopper penguins and southern sub-Antarctic
penguins using the Subtropical Convergence, a major ecological boundary
for marine organisms, as the dividing line between them. Their results
supported the separation of E. chrysocome into two species, the
southern rockhopper (E. chrysocome) and the northern rockhopper (E.
moseleyi).
Another recently published paper in the journal Polar Biology
confirmed that there is more than one species of rockhopper penguins.
Banks et al. (2006, pp. 61-67) compared the genetic distances between
the three rockhopper subspecies and compared them with such sister
species as macaroni penguins. Banks et al. (2006, pp. 61-67) suggested
that three rockhopper subspecies--southern rockhopper (currently E.
chrysocome chrysocome), eastern rockhopper (currently E. chrysocome
filholi), and northern rockhopper (currently E. chrysocome moseleyi)--
should be split into three species.
BirdLife International (2007, p. 1) has reviewed these two papers
and made the decision to adopt, for the purposes of their continued
compilation of information on the status of birds, the conclusion of
Jouventin et al. (2006, p. 3,419) that there are two species of
rockhopper penguin. In doing so, they noted that the proposed splitting
of an eastern rockhopper species from E. chrysocome has been rejected
on account of weak morphological differentiations between the
circumpolar populations south of the Subtropical Convergence (Banks et
al. 2006, p. 67). Furthermore those two groups are more closely related
to each other in terms of genetic distance than either is to the
northern rockhopper penguin (Banks et al. 2006, p. 65).
We conclude that, while both analyses have merit, the split into a
northern and southern species on the basis of both genetic and
morphological differences represents the best available science. On the
basis of our review, we accept the BirdLife International treatment of
the rockhopper penguins as two species: The northern rockhopper penguin
(E. moseleyi) and the southern rockhopper penguin (E. chrysocome).
Life History
The life histories of northern and southern rockhopper penguins are
similar. Breeding begins in early October (the austral spring) when
males arrive at the breeding site a few days before females. Breeding
takes place as soon as the females arrive, and two eggs are laid 4-5
days apart in early November. The first egg laid is typically smaller
than the second, 2.8 versus 3.9 ounces (oz) (80 versus 110 grams (g)),
and is the first to hatch. Incubation lasts about 33 days and is
divided into three roughly equal shifts. During the first 10-day shift,
both parents are in attendance. Then, the male leaves to feed while the
female incubates during the second shift. The male returns to take on
the third shift. He generally remains for the duration of incubation
and afterward to brood the chicks while the female leaves to forage and
returns to feed the chicks. Such a system of extended shift duration
requires lengthy fasts for both parents, but allows them to forage
farther afield than would be the case if they had a daily change-over.
The newly hatched chicks may have to wait up to a week before the
female returns with their first feed. During this period, chicks are
able to survive on existing yolk reserves, after which they begin
receiving regular feedings of around 5 oz (150 g) in weight. By the end
of the 25 days of brooding, chicks are receiving regular feedings
averaging around 1 lb 5 oz (600 g). By this stage they are able to
leave the nest and cr[egrave]che with other chicks, allowing both
adults to forage to meet the chicks' increasing demands for food
(Marchant and Higgins 1990, p. 190).
Northern rockhopper penguins and birds in the eastern colonies of
southern rockhopper penguins typically rear only one of the two chicks.
However, southern rockhopper penguins near the Falkland Islands are
capable of rearing both chicks to fledging when conditions are
favorable (Guinard et al. 1998, p. 226). In spite of this difference,
southern rockhopper penguins average successful breeding of one chick
per pair annually for the colony as a whole. Chicks fledge at around 10
weeks of age, and adults then spend 20-25 days at sea building up body
fat reserves in preparation for their annual molt. The molt lasts for
around 25 days, and the birds then abandon the breeding site. They
spend the winter feeding at sea, prior to returning the following
spring (Marchant and Higgins 1990, p. 185).
The range of southern and northern rockhopper penguins includes
breeding habitat on temperate and sub-Antarctic islands around the
Southern Hemisphere and marine foraging areas. In the breeding season,
these marine foraging areas may lie within as little as 6 miles (mi)
(10 kilometers (km)) of the colony (as at the Crozet Archipelago in the
Indian Ocean), as distant as 97 mi (157 km) (as at the Prince Edward
Islands in the Indian Ocean), or for male rockhoppers foraging during
the incubation stage at the Falkland Islands in the Southwest Atlantic,
as much as 289 mi (466 km) away (Sagar et al. 2005, p. 79; Putz et al.
2003b, p. 141). Foraging ranges vary according to the geographic,
geologic, and oceanographic location of the breeding sites and their
proximity to sea floor features (such as the continental slope and its
margins or the sub-Antarctic slope) and oceanographic features (such as
the polar frontal zone or the Falkland current) (Sagar et al. 2005, pp.
79-80). Winter at-sea foraging areas are less well-documented, but
penguins from the Staten Island breeding colony at the tip of South
America dispersed over a range of 501,800 square miles (mi\2\) (1.3
million square kilometers (km\2\)) covering polar, sub-polar, and
temperate waters in oceanic regions of the Atlantic and Pacific as well
as shelf waters (Putz et al. 2006, p. 735) and traveled up to 1,242 mi
(2,000 km) from the colony.
Southern Rockhopper Penguin
Distribution
The southern rockhopper penguin (Eudyptes chrysocome) is widely
distributed around the Southern Ocean, breeding on many sub-Antarctic
islands in the Indian and Atlantic Oceans (Shirihai 2002, p. 71). The
species breeds on the Falkland Islands (United Kingdom, Argentina),
Penguin and Staten Islands (Argentina) at the southern tip of South
America, and islands of southern Chile. Farther to the east, the
southern rockhopper penguin breeds on Prince Edward Islands (South
Africa); Crozet and Kerguelen Islands (French Southern Territories);
Heard, McDonald, and Macquarie Islands (Australia); and Campbell,
Auckland, and Antipodes Islands (New Zealand) (BirdLife International
2007, pp. 2-3; Woehler 1993, pp. 58-61).
[[Page 77267]]
Population
Falkland Islands
At the Falkland Islands, between the census in 1932-33 and the
census in 1995-96, there was a decline of more than 80 percent, with an
overall rate of decline of 2.75 percent per year (Putz et al. 2003a, p.
174). Reports of even greater declines (Bingham 1998, p. 223) have been
revised after re-analysis of the original 1930's census data, which
recorded an estimated 1.5 million southern rockhopper breeding pairs
(Putz et al. 2003a, p. 174). The census in 2000-01 of 272,000 breeding
pairs indicated stable numbers since the mid-1990s (297,000 breeding
pairs) in the Falkland Islands (Clausen and Huin 2003, p. 389),
although further declines since then (Putz et al. 2006, p. 742), and a
lower figure of 210,000 breeding pairs in 2005-06, have been cited
(Kirkwood et al. 2007, p. 266).
The declines of southern rockhoppers in the Falkland Islands appear
not to have been gradual. Clausen and Huin (2003, p. 394) state that
``circumstantial evidence'' suggests that in the early 1980s, there
were no more than 500,000 pairs, a decline of 66 percent since the
1930s. By the mid-1990s, the total decline had reached 80 percent. A
mass mortality event in the 1985-86 breeding season killed thousands of
penguins and was linked to starvation before molt (Putz et al. 2003a,
p. 174; Keyme et al. 2001, p. 168). In summary, although there has been
a long-term decline in numbers at the Falkland Islands, numbers have
not declined at a consistent rate, but rather, there have been periodic
declines over a long period of time. As mentioned below, Schiavini
(2000, p. 290) suggested that Falkland Island birds may be dispersing
to Staten Island, potentially contributing to the stable or increasing
numbers there.
Southern Tip of South America
In the region of the southern tip of South America, large numbers
of southern rockhopper penguins are reported with approximately 180,000
breeding pairs in southern Argentina at Staten Island (Schiavini 2000,
p. 286; Kirkwood et al. 2007, p. 266), 134,000 breeding pairs at Isla
Noir (Oehler 2005, p. 7), 86,400 breeding pairs at Ildefonso
Archipelago, and 132,721 breeding pairs at Diego Ramirez Archipelago
(Kirkwood et al. 2007, p. 265). Kirkwood et al. (2007, p. 266)
concluded that numbers for the southern tip of South America are
approximately 555,000 breeding pairs. These relatively recent estimates
are substantially larger than previous estimates of 175,000 breeding
pairs reported in Woehler (1993, p. 61), but it is unclear whether this
reflects population increases or more comprehensive surveys. In the
Chilean archipelago, Kirkwood et al. (2007, p. 266) found no
substantive evidence for overall changes in the number of penguins
between the early 1980s and 2002, although one colony in the region
(the Isla Recalada colony, a historical breeding site) declined from
10,000 pairs in 1989 to none in 2005 (Oehler et al. 2007, p. 505). On
the Argentine side, Schiavini (2000, p. 290) stated that the numbers at
Staten Island are stable or increasing, perhaps as a result of a flux
of birds from the Falkland Islands. In summary, the overall number of
southern rockhopper penguins at the Falklands and the southern tip of
South America is estimated at 765,000 breeding pairs distributed as
follows: Falkland Islands, 27 percent; Argentina, 24 percent; and
Chile, 48 percent. Based on the available information, there does not
appear to be a declining trend in southern rockhopper penguin numbers
on the southern tip of South America. Although there may have been
population increases in the region based on the reported population
numbers, it is unclear if these higher numbers reflect true increases
in numbers, more comprehensive surveys, or movement of other penguins
from the Falkland Islands.
Prince Edward Islands
Two species of Eudyptes penguins breed at Marion Island (46.9
degrees ([deg]) South (S) latitude, 37.9[deg] East (E) longitude), one
of two islands in the sub-Antarctic Prince Edward Islands group in the
southwest Indian Ocean. They are the southern rockhopper penguin (E.
chrysocome) and the macaroni penguin (E. chrysolophus). For southern
rockhopper penguins, the numbers of birds estimated to breed at Marion
Island decreased by 61 percent from 173,000 pairs in 1994-95 to 67,000
pairs in 2001-02 (Crawford et al. 2003, p. 490). The number of southern
rockhopper penguins at nearby Prince Edward Island appears to have been
stable since the 1980s with 35,000-45,000 pairs present (Crawford et
al. 2003, p. 496). The decreases at Marion Island are thought to result
from poor breeding success, with fledging rates lower than required for
the colonies to remain in equilibrium; a decrease in the mass of males
and females on arrival at the colony for breeding; and low mass of
chicks at fledging (Crawford et al. 2003, p. 496). These changes are
attributed to an inadequate supply of food for southern rockhopper
penguins at Marion Island (Crawford et al. 2003, p. 487), presumably
from a decrease in the availability of crustaceans or competition with
other predators for food (Crawford et al. 2003, p. 496). Winter grounds
of southern rockhopper penguins are not known. However, over-wintering
conditions, which are reflected in the condition of birds arriving to
breed, influence the proportion of adults that breed in the following
summer and the outcome of breeding (Crawford et al. 2006, p. 185).
Crozet and Kerguelen Islands
Jouventin et al. (2006, p. 3,417) referenced 1984 data from French
Indian Ocean territories that showed 264,000 breeding pairs at Crozet
Islands and 200,000 breeding pairs at Kerguelen Island. These figures
did not agree with those presented by Woehler (1993, pp. 59-60) and, if
accurate, represent an increase of about 25 percent for the Crozet
Islands and over 100 percent for Kerguelen. We are not aware of
reported declines at the Crozet and Kerguelen Islands.
Heard, McDonald, and Macquarie Islands
Numbers at Heard and McDonald Islands (Australia) are reported as
small, with an ``order of magnitude estimate'' of greater than 10,000
pairs for Heard Island and greater than 10 pairs for McDonald (Woehler
1993, p. 60). No information has been reported on trends in numbers in
these areas. Order of magnitude estimates at Macquarie Island
(Australia) reported 100,000-300,000 pairs in the early 1980s (Woehler
1993, p. 60; Taylor 2000, p. 54). The 2006 Management Plan for the
Macquarie Island Nature Reserve and World Heritage Area reported that
the total number of southern rockhopper penguins in this area may be as
high as 100,000 breeding pairs, but estimates from 2006-07 indicate
32,000-43,000 breeding pairs at Macquarie Island (BirdLife
International 2008b, p. 2). Given the large range in the earlier
categorical estimate, we cannot evaluate whether the more recent
estimate represents a decline in numbers or a more precise estimate.
Campbell, Auckland, and Antipodes Islands
In New Zealand territory, southern rockhopper numbers at Campbell
Island declined by 94 percent between the early 1940s and 1985 from
approximately 800,000 breeding pairs to 51,500 (Cunningham and Moors
1994, p. 34). The majority of the decline appears to have coincided
with a period of warmed sea surface temperatures
[[Page 77268]]
between 1946 and 1956. It is widely inferred that warmer waters most
likely affected southern rockhopper penguins through changes in the
abundance, availability, and distribution of their food supply
(Cunningham and Moors 1994, p. 34); recent research suggests they may
have had to work harder to find the same food (Thompson and Sagar 2002,
p. 11). According to standard photographic monitoring, numbers in most
colonies at Campbell Island continued to decline from 1985 to the mid-
1990s (Taylor 2000, p. 54), although the extent of such declines has
not been quantified in the literature. The New Zealand Department of
Conservation (DOC) provided preliminary information from a 2007
Campbell Island survey team that ``the population is still in decline''
(D. Houston 2008, p. 1), but quantitative analysis of these data have
not yet been completed. At the Auckland Islands, a survey in 1990 found
10 colonies produced an estimate of 2,700-3,600 breeding pairs of
southern rockhopper penguins (Cooper 1992, p. 66). This was a decrease
from 1983, when 5,000-10,000 pairs were counted (Taylor 2000, p. 54).
There has been a large decline at Antipodes Islands from 50,000
breeding pairs in 1978 to 3,400 pairs in 1995 (Taylor 2000, p. 54).
There is no more recent data for Auckland or Antipodes Islands (D.
Houston 2008, p. 1).
Other Status Classifications
The IUCN (International Union for Conservation of Nature) Red List
classifies the southern rockhopper penguin as `Vulnerable' due to rapid
population declines, which ``appear to have worsened in recent years.''
Summary of Factors Affecting the Species
Factor A: The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Terrestrial Habitat
There are few reports of destruction, modification, or curtailment
of the terrestrial habitat of the southern rockhopper penguin. Analyses
of large-scale declines of southern rockhopper penguins have uniformly
ruled out that impacts to the terrestrial habitat have been a limiting
factor to the species (Cunningham and Moors 1994, p. 34; Keyme et al.
2001, pp. 159-169; Clausen and Huin 2003, p. 394), and we have no
reason to believe threats to the terrestrial habitat will emerge in the
foreseeable future.
Climate-Related Changes in the Marine Environment
Reports of major decreases in southern rockhopper penguin numbers
have been linked to sea surface temperature changes and other apparent
or assumed oceanographic or prey shifts in the vicinity of southern
rockhopper penguin breeding colonies or their wintering grounds. Actual
empirical evidence of changes has been difficult to compile, and
conclusions of causality for observations at one site are often
inferred from data from other studies at other sites, which may or may
not be pertinent. In the most cited study, Cunningham and Moors (1994,
pp. 27-36) concluded that drastic southern rockhopper penguin declines
were related to increased sea surface temperature changes at Campbell
Island in New Zealand. In another study, Crawford et al. (2003, p. 496)
hypothesized altered distribution or decreased abundance of marine prey
at Marion Island, where mean sea surface temperature increased by 2.5
degrees Fahrenheit ([deg]F) (1.4 degrees Celsius ([deg]C)) between 1949
and 2002, as a factor in a decline of southern rockhopper penguin
numbers by 61 percent during that period (Crawford and Cooper 2003, p.
415). Clausen and Huin (2003, p. 394), in discussing the factors that
may be responsible for large-scale declines in this species at the
Falkland Islands since the 1930s (and especially in the mid-1980s),
found the most plausible explanation to be changes in sea surface
temperatures, which could in turn affect the available food supply
(Clausen and Huin 2003, p. 394). Extreme El Ni[ntilde]o-like warming of
surface waters occurred during the 1985-86 period when the most severe
decline occurred at the Falkland Islands (Boersma 1987, p. 96; Keyme et
al. 2001, p. 168). None of these authors cites historical fisheries
data to corroborate the hypothesis that prey abundance has been
affected by changes in sea surface temperatures.
As noted above, changes in oceanographic conditions and their
possible impact on prey have been cited in reports of southern
rockhopper penguin declines around the world (Cunningham and Moors
1994, pp. 27-36; Crawford et al. 2003, p. 496; Crawford and Cooper
2003, p. 415; Clausen and Huin 2003, p. 394). We examine the case of
Campbell Island in depth in the following paragraphs, since this
provides the most studied example.
At Campbell Island, a 94-percent decrease in southern rockhopper
penguin numbers occurred between the early 1940s and 1985. Cunningham
and Moors (1994, pp. 27-36) compared the pattern of the penguin decline
(from 800,000 breeding pairs in the early 1940s to 51,500 pairs in
1985) to patterns of sea surface temperature change. The authors
concluded that drastic southern rockhopper penguin declines were
related to increased sea surface temperature changes at Campbell
Island. They found that peaks in temperature were related to the
periods of largest decline in numbers within colonies, in particular in
1948-49 and 1953-54. One study colony rebounded in cooler temperatures
in the 1960s; however, with temperature stabilization at higher levels
(mean 49.5 [deg]F (9.7 [deg]C)) in the 1970s, declines continued.
Colony sizes have continued to decline into the 1990s (Taylor 2000, p.
54), and preliminary survey data indicate that numbers at Campbell
Island continue to decline (Houston 2008, p. 1).
Cunningham and Moors (1994, p. 34) concluded that warmer waters
most likely affected the diet of the Campbell Island southern
rockhopper penguins. In the absence of data on the 1940's diet of
Campbell Island southern rockhopper penguins, the authors compared the
1980's diet of the species at Campbell Island to southern rockhopper
penguins elsewhere. They found the Campbell Island penguins eating
primarily fish--southern blue whiting (Micromesisteus australis), dwarf
codling (Austrophycis marginata), and southern hake (Merluccius
australis)--while elsewhere southern rockhopper penguins were reported
to eat mainly euphausiid crustaceans (krill) and smaller amounts of
fish and squid. Based on this comparison of different areas, the
authors concluded that euphausiids left the Campbell Island area when
temperatures changed, forcing the southern rockhopper penguins to adopt
an apparently atypical, and presumably less nutritious, fish diet. The
authors concluded that this led to lower departure weights of chicks
and contributed to adult declines (Cunningham and Moors 1994, p. 34).
Subsequent research, however, has not supported the theory that
southern rockhopper penguins at Campbell Island switched prey as their
``normal'' euphausiid prey moved to cooler waters (Cunningham and Moors
1994, pp. 34-35). This hypothesis has been tested through stable
isotope studies, which can be used to extract historical dietary
information from bird tissues (e.g., feathers). In analyses of samples
from the late 1800s to the present at Campbell Island and Antipodes
Islands, Thompson and Sagar (2002, p. 11) found no evidence of a shift
in southern rockhopper penguin diet during the
[[Page 77269]]
period of decline. They concluded that southern rockhopper penguins did
not switch to a less suitable prey, but that overall marine
productivity and the carrying capacity of the marine ecosystem declined
beginning in the 1940s. With food abundance declining or food moving
farther offshore or into deeper water, according to these authors, the
southern rockhopper penguins maintained their diet over the long
timescale, but were unable to find enough food in the less productive
marine ecosystem (Thompson and Sagar 2002, p. 12).
Hilton et al. (2006, pp. 611-625) expanded the study of carbon
isotope ratios in southern and northern rockhopper penguin feathers to
most breeding areas, except those at the Falkland Islands and the tip
of South America, to look for global trends that might help explain the
declines observed at Campbell Island. They found no clear global-scale
explanation for large spatial and temporal-scale rockhopper penguin
declines. While they found general support for lower primary
productivity in the ecosystems in which rockhopper penguins feed, there
were significant differences between sites. There was evidence of a
shift in diet to lower trophic levels over time and in warm years, but
the data did not support the idea that the shift toward lower primary
productivity reflected in the diet resulted from an overall trend of
rising sea temperatures (Hilton et al. 2006, p. 620). No detectable
relationship between carbon isotope ratios and annual mean sea surface
temperatures was found (Hilton et al. 2006, p. 620).
In the absence of conclusive evidence for sea surface temperature
changes as an explanation for reduced primary productivity, Hilton et
al. (2006, p. 621) suggested that historical top-down effects in the
food chain might have caused a reduction in phytoplankton growth rates.
Reduced grazing pressure resulting from the large-scale removal of
predators from the sub-Antarctic could have resulted in larger standing
stocks of phytoplankton, which in turn could have led to lowered cell
growth rates (which would be reflected in isotope ratios), with no
effect on overall productivity of the system. Postulated top-down
effects on the ecosystem of southern rockhopper penguins, which
occurred in the time period before the warming first noted in the
original Cunningham and Moors (1994, p. 34) study, are the hunting of
pinniped populations to near extinction in the 18th and 19th centuries
and the subsequent severe exploitation of baleen whale
(Balaenopteridae) populations in the 19th and 20th centuries (Hilton et
al. 2006, p. 621). While this top-down theory may explain the regional
shift toward reduced primary productivity, it does not explain the
decrease in abundance of food at specific penguin breeding and foraging
areas.
Hilton et al. (2006, p. 621) concluded that considerably more
development of the links between isotopic monitoring of rockhopper
penguins and the analysis of larger-scale oceanographic data is needed
to understand effects of human activities on the sub-Antarctic marine
ecosystem and the links between rockhopper penguin demography, ecology,
and environment.
Meteorologically, the events described for Campbell Island from the
1940s until 1985, including the period of oceanic warming, occurred
after a record cool period in the New Zealand region between 1900 and
1935, the coldest period since record-keeping began (Cunningham and
Moors 1994, p. 35). These historical temperature changes have been
attributed to fluctuations in the position of the Antarctic Polar Front
caused by changes in the westerly-wind belt (Cunningham and Moors 1994,
p. 35). Photographic evidence suggests that southern rockhopper penguin
numbers may have been significantly expanding as the early 1900s cool
period came to an end (Cunningham and Moors 1994, p. 33) and just
before the rapid decrease in numbers.
Without longer-term data sets on southern rockhopper fluctuations
in numbers of penguins at Campbell Island and longer temperature data
records at a scale appropriate to evaluating impacts on this particular
breeding colony, it is difficult to draw conclusions on the situation
described there. There are even fewer data for Auckland and Antipodes
Islands.
For now, local-scale observations may be of more utility in
explaining mass declines of southern rockhopper penguins. At the
Falkland Islands, the mass starvation event of 1985-86 coincided with a
Pacific El Nino event, and the unusually long and hot southern summer
in the southwest Atlantic was analogous to the Pacific El Nino (Boersma
1987, p. 96; Keyme et al. 2001, p. 160). There was an influx of warm
water seabirds from the north, indicating movement of warm water into
the area, and it was hypothesized that warm weather negatively affected
the growth and presence of food in a manner similar to what occurs when
the warm El Nino current extends southwards off the Pacific coast of
Peru. Perturbations of upwellings essential to sustaining the normal
food chain appear to have been caused by unusually strong westerly
winds in the Atlantic, with prey failure leading to a starvation event
(Boersma 1987, p. 96; Keyme et al. 2001, p. 168). The severe El Nino
event of 1996-97 has also been cited as a possible factor in the
decline and disappearance of the small Isla Recalada colony in Chile,
with the suggestion that response to this climatic event may have been
one factor leading birds at this colony to disperse to other areas such
as the large Isla Noir colony 75 mi (125 km) away (Oehler et al. 2007,
pp. 502, 505).
In other local-scale observations, studies of winter behavior of
southern rockhopper penguins foraging from colonies at Staten Island,
Argentina, indicated that penguins respond behaviorally to different
oceanographic conditions such as seasonal differences in sea surface
temperatures by changing foraging strategies. Even with such behavioral
plasticity, differences in winter foraging conditions (for example,
between an average and a cold year) led to differences in adult
survival, return rates to breeding colonies, and breeding success
between years (Rey et al. 2007, p. 285).
Changes in the marine environment and possible shifts in food
abundance or distribution in the marine environment have been cited as
leading to historical and present-day declines in three areas within
the distribution of southern rockhopper penguins around the world--the
Falkland Islands in the South Atlantic (80-percent decline), Marion
Island in the Indian Ocean (61-percent), and the New Zealand sub-
Antarctic islands (Campbell Island (94-percent), Auckland Island (50-
percent), and the Antipodes Islands (93-percent)).
While southern rockhopper penguin numbers have declined in some
areas, there are significant areas of the southern rockhopper range
(representing about one million pairs) where numbers have remained
stable or increased. This indicates that the severity and pervasiveness
of these factors in the marine environment are not uniform throughout
the species' range. For example, declines have been reported at the
Falkland Islands; however, nearby colonies at the southern tip of South
America appear to have increased and now represent 72 percent of
southern rockhopper abundance in the larger south Atlantic and
southeast Pacific region. Similarly, at the Prince Edward Islands,
declines have been documented at Marion Island; however, colonies at
nearby Prince Edward Island have remained stable. As noted above, in
large areas of the Indian Ocean, including the French Indian Ocean
territories at Kerguelen
[[Page 77270]]
and Crozet Islands, large numbers are stable or increasing.
This difference in trends in locations within the species' range,
and the limitation of declines to regional areas, illustrates that
while temperature changes in the marine environment have been widely
cited as an indicator of changing oceanographic conditions for southern
rockhopper penguins, there is not a unitary explanation for phenomena
observed in the widely scattered breeding locations across the Southern
Hemisphere. In fact, as illustrated for the most studied example at
Campbell Island, a detailed analysis of causality has so far led to
further questions, rather than a narrowing down of answers.
Nevertheless, in the absence of any major factors on land, the best
available information indicates that some change in the oceanographic
ecosystem has led to past declines in southern rockhopper penguins in
some regions and has the potential to lead to future declines in
southern rockhopper penguin colonies in those regions of New Zealand.
Large-scale measurements show that temperature changes have been
occurring in the Southern Ocean since the 1960s. Overall, the upper
ocean has warmed since the 1960s with dominant changes in the thick
near-surface layers called ``sub-Antarctic Mode waters,'' located just
north of the Antarctic Circumpolar Current (ACC) (Bindoff et al. 2007,
p. 401). In mid-depth waters--2,952 feet (ft) (900 meters (m))--
temperatures have increased throughout most of the Southern Ocean,
having risen 0.31 [deg]F (0.17 [deg]C) between the 1950s and 1980s
(Gille 2002, p. 1,275). However, the ocean temperature trends described
are at too large a scale to relate meaningfully to the demographics of
the southern rockhopper penguins, whether at any single penguin colony
or breeding or foraging area, or to the variation in trends in colonies
around the world at larger scales. We have noted above that attempts to
ascribe trends in rockhopper penguin numbers to large-scale sea-
temperature changes using biological measurements of southern
rockhopper population and foraging parameters have been unsuccessful in
revealing any causal links.
Despite larger-scale conclusions that Southern Ocean warming is
occurring, we have not identified sea temperature data on an
appropriate oceanographic scale to evaluate either historical trends or
to make predictions on future trends and whether they will affect
southern rockhoppers across the New Zealand/Australia region. For
example, Gille (2002, p. 1,276) presented a figure of historical
Southern Ocean deep-water temperatures to illustrate an overall warming
trend. However, while the scale of measurement is too large to draw any
conclusions at a local-scale, in the region of the New Zealand/
Australia portion of the species' range, the figure provided appears to
show that ocean temperatures have decreased on average from the 1950s
to the 1990s.
Looking at the situation from the perspective of physical
oceanography, attempts to describe the relationship between southern
rockhopper penguin population trends and trends in ocean temperatures,
based on large-scale oceanographic observations of temperature trends
in the Southern Ocean, and to arrive at historical or predictive models
of the impact of temperature trends on penguins are equally difficult.
Such analyses are hampered by: (1) The fact that measurements of
temperature and temperature trends are provided at an ocean-wide scale;
(2) the measurement and averaging of temperatures over large water
bodies or depths, which do not allow analysis of impacts at any one
site or region or allow explanation of divergent trends between
colonies in the same region; (3) lack of real-time data on temperature
and trends at biologically meaningful geographical scales in the
vicinity of breeding or foraging habitat for penguins; and (4) absence
of consistent monitoring of southern rockhopper penguin abundance and
demographic and biological parameters to relate to such oceanographic
measurements. We have insufficient information to draw conclusions on
whether directional changes in ocean temperatures are affecting
southern rockhopper penguins throughout all of their range.
We have examined areas of the range of the southern rockhopper
penguin where numbers have declined, such as at Campbell Island and the
Falkland Islands. At the same time, numbers in the majority of the
range of the southern rockhopper penguin have remained stable or
increased. For example, in the region of the southern tip of South
America, numbers have increased and now represent 72 percent of
southern rockhopper abundance in the larger south Atlantic and
southeast Pacific regions. At the Prince Edward Islands, declines at
Marion Island have been accompanied by stability at nearby Prince
Edward Island. At Kerguelen and Crozet Islands, numbers are increasing
or stable.
Within the New Zealand/Australia portion of the species' range, the
New Zealand islands have experienced severe declines; however, trend
information for the Australian Macquarie Island colonies is much less
certain, given the poor quality of the baseline estimate at Macquarie.
Based on our review of the best available information (see above), we
conclude that changes to the marine environment, which influence the
southern rockhopper penguin, have affected the Campbell Plateau, but
their effects on the Macquarie Ridge region are unknown. In the absence
of identification of other significant threat factors and in light of
the best available scientific information indicating that prey
availability, productivity, or sea temperatures are affecting southern
rockhopper penguins within the Campbell Plateau, we find that changes
to the marine environment is a threat to the Campbell Plateau colonies
of southern rockhopper penguins at Campbell, Auckland, and Antipodes
Islands.
While rockhopper penguin numbers in certain areas of the species'
range have been affected by changes to the marine environment, numbers
in the majority of the range are stable or increasing. This indicates
that the severity and pervasiveness of stressors in the marine
environment are not uniform throughout the species' range, and we have
not identified sea-temperature data on an appropriate oceanographic
scale to be able to identify broad-scale trends or to make predictions
on future trends about whether changes to the marine environment will
affect southern rockhoppers penguins either across its range or within
the New Zealand/Australia region.
On this basis, we find that the present or threatened destruction,
modification, or curtailment of both its terrestrial and marine
habitats is not a threat to the southern rockhopper penguin throughout
all of its range now or in the future.
Factor B: Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Despite the overall increase in southern rockhopper penguin numbers
in southern Chile, the Isla Recalada colony--a historical breeding
site--declined from 10,000 pairs in 1989 to none in 2005 (Oehler et al.
2007, p. 505). In attempting to explain this local decline, Oehler et
al. (2007, p. 505) cited the collection of adult penguins for export to
zoological parks from 1984-1992 as a disturbance that may have caused
adult penguins to move to other areas, but this has not been verified.
The authors also reported that between 1992 and 1997, in times of
shortage of fish
[[Page 77271]]
bait, local fishermen harvested adult southern rockhopper penguins at
the Isla Recalada colony for bait for crab pots (Oehler et al. 2007, p.
505), but we have no information on the effect of this stressor in
terms of numbers of individuals lost from the colony.
Collection for zoological parks is now prohibited, and the species
is not found in trade (Ellis et al. 1998, p. 54). There is no
information that suggests this ban will be lifted in the future.
Tourism and other human disturbance impacts are reported to have
little effect on southern rockhopper penguins (BirdLife International
2007, p. 3).
In summary, although there is some evidence of historical and even
relatively recent take of southern rockhopper penguins from the wild
for human use, collection for zoological parks is no longer occurring,
and other harvest that may be occurring for fish bait is not on a large
enough scale to be a threat to this species. We have no reason to
believe the levels of utilization will increase in the future.
Therefore, we find that overutilization for commercial, recreational,
scientific, or educational purposes is not a threat to the species in
any portion of its range now or in the future.
Factor C: Disease or Predation
Investigations have ruled out disease as a significant factor in
major population declines at Campbell Island in the 1940s and 1950s or
in the sharp declines in the mid-1980s at the Falkland Islands. At
Campbell Island, de Lisle et al. (1990, pp. 283-285) isolated avian
cholera (Pasteurella multocida) from the lungs of dead chicks and
adults sampled during the year of decline 1985-86 and the subsequent
year 1986-87. They were unable to determine whether this was a natural
infection in southern rockhopper penguins or one that had been
introduced through the vectors of rats, domestic poultry, cats (Felis
catus), dogs (Canis familiaris), or livestock that have been prevalent
on the island in the past. While the disease was isolated in four
separate colonies along the coast of Campbell Island, and there was
evidence of very limited mortality from the disease, the authors
concluded there was no evidence that mortality from this pathogen on
its own may have caused the decline in numbers at Campbell Island
(Cunningham and Moors 1994, p. 34). Assays for a variety of other
infectious avian diseases found no antibody responses in southern
rockhopper penguins at Campbell Island (de Lisle et al. 1990, pp. 284-
285).
Following the precipitous decline of southern rockhopper penguins
at the Falkland Islands in the 1985-86 breeding season, examinations
and full necropsies were carried out for a large number of individuals.
Mortality was primarily attributed to starvation. A large number of
predisposing factors were ruled out, such as anthropogenic factors
(oiling, fish net mortality, ingestion of plastic, trauma, or trapping
at sea or on breeding grounds) or natural causes (heavy predation on or
near breeding grounds, botulism at the breeding grounds, or
dinoflagellate poisoning caused by red tides). Infectious diseases were
considered in depth, but no specific disease was identified (Keyme et
al. 2001, p. 166). A secondary factor, ``puffinosis,'' caused ulcers on
the feet of some young penguins, but no mortality was associated with
these lesions (Keyme et al. 2001, p. 167). Examination for potential
toxic agents found high tissue concentrations for only cadmium;
however, cadmium levels did not differ between the year of high
mortality and the subsequent year when no unusual mortality occurred
(Keyme et al. 2001, pp. 163-165).
Bester et al. (2003, pp. 549-554) reported on the recolonization of
sub-Antarctic fur seals (Arctocephalus tropicalis) and Antarctic fur
seals (Arctocephalus gazelle) at Prince Edward Island. Rapid fur seal
recolonization is taking place at this island. There are now an
estimated minimum 72,000 sub-Antarctic fur seals (Bester et al. 2003,
p. 553); the population has grown 9.5 percent annually since 1997-98.
Similarly, at Marion Island, sub-Antarctic fur seal populations
increased exponentially between 1975 and 1995. Adult populations were
49,253 animals in 1994-95. Crawford and Cooper (2003, p. 418) expressed
concern that the burgeoning presence of seals at Prince Edward and
Marion Islands may be increasingly affecting southern rockhopper
penguins through physical displacement from nesting sites, prevention
of access to breeding sites, direct predation, and increasing
competition between southern rockhopper penguins and seals for prey;
however, these potential effects of fur seals on southern rockhopper
penguins have not been investigated.
At Campbell Island in New Zealand, de Lisle et al. (1990, p. 283)
ruled out Norway rats (Rattus norvegicus), which were present on the
island at the time of precipitous declines, as a factor in those
declines. Feral cats are present on Auckland Island, but have not been
observed preying on chicks there (Taylor 2000, p. 55). Although it was
suggested that introduced predators may affect breeding on Macquarie
and Kerguelen Islands (Ellis et al. 1998, p. 49), no information was
provided to support this idea.
In summary, based on our review of the best available information
we find that neither disease nor predation is a threat to the southern
rockhopper penguin in any portion of its range, and no information is
available that suggests this will change in the future.
Factor D: The Inadequacy of Existing Regulatory Mechanisms
The majority of sub-Antarctic islands are under protected status.
For example, all New Zealand sub-Antarctic islands are nationally
protected and inscribed as the New Zealand Subantarctic Islands World
Heritage sites; human visitation of the islands is tightly restricted
at all sites where penguins occur (Taylor 2000, p. 54; BirdLife
International 2007, p. 4; UNEP WCMC (United Nations Environmental
Program, World Conservation Monitoring Center) 2008a, p. 5). The
Australian islands of Macquarie, Heard, and McDonald are also World
Heritage sites with limited or no visitation and with management plans
in place (UNEP WCMC 2008b, p. 6; UNEP WCMC 2008c, p. 6). In 1995, the
Prince Edward Islands Special Nature Preserve was declared and
accompanied by the adoption of a formal management plan (Crawford and
Cooper 2003, p. 420). Based on our review of the existing regulatory
mechanisms in place for each of these areas and our analysis of other
threat factors, we find that the only inadequacy in existing regulatory
mechanisms regarding the conservation of the southern rockhopper
penguin (BirdLife International 2007, p. 4; Ellis et al. 1998, pp. 49,
53) to be the inability to ameliorate the effects of changes to the
marine environment on the species in the Campbell Plateau portion of
its range.
In Chile, collection for zoological display, which used to be
permitted, is now prohibited, and the species is not found in trade
(Ellis et al. 1998, p. 54). Fisheries activities in the Falkland
Islands, which have increased dramatically since the 1970s, are now
closely regulated. A series of conservation zones has been established,
and the number of vessels fishing within these zones is regulated to
prevent fish and squid stocks from becoming depleted. The Falkland
Island Seabird Monitoring Program has been established to collect
baseline data essential to identifying and detecting potential threats
to seabirds (Putz et al.
[[Page 77272]]
2001, p. 794). As discussed under Factor E, current licensing
arrangements limit squid harvest to between the beginning of February
and the end of May and the beginning of August and the end of October,
which minimizes overlap with the southern rockhopper penguin breeding
season, when feeding demands are high (October to February) (Putz et
al. 2001, p. 803).
In summary, aside from the inadequacy of regulatory mechanisms to
ameliorate the threat of changes in the marine environment in the
Campbell Plateau portion of the species' range, we find that the
existing national regulatory mechanisms are adequate regarding the
conservation of southern rockhopper penguins in all other parts of the
species' range. There is no information available to suggest these
regulatory mechanisms will change in the future.
Factor E: Other Natural or Manmade Factors Affecting the Continued
Existence of the Species
Fisheries
While competition for prey with commercial fisheries has been
listed as a potential factor affecting southern rockhopper penguins in
various portions of their range (Ellis et al. 1998, pp. 49, 53), we
have found that it is only in the Falkland Islands where this potential
competition between commercial fisheries and southern rockhopper
penguins has emerged and been addressed. Bingham suggests that rapid
southern rockhopper penguin declines at the Falkland Islands in the
1980's were a result of uncontrolled commercial fishing (but see
analysis of El Nino under Factor A), but reports that following the
establishment of a regulatory body in 1988, the effects of over-fishing
at the Falkland Islands have been greatly mitigated (Bingham 2002, p.
815), and southern rockhopper penguin populations have stopped
declining. At the Falkland Islands, the inshore area adjacent to
colonies is not subject to fishing activities (Putz et al. 2002, p.
282). The diet of southern rockhopper penguins, in general, is
dominated by crustaceans, with fish and squid varying in importance. At
the Falkland Islands, squid, in particular Patagonian squid (Loligo
gahi), is of greater importance in the diet than in other rockhopper
penguins (Putz et al. 2001, p. 802). The Patagonian squid is also an
important commercial species fished around the Falkland Islands.
Current licensing arrangements limit squid harvest to between the
beginning of February and the end of May and the beginning of August
and the end of October, which minimizes overlap with the southern
rockhopper penguin breeding season, when feeding demands are high
(October to February). Nevertheless, reports of decreasing catch per
unit of effort for squid indicate a declining squid stock over the
1990s (Putz et al. 2001, p. 803). Coincidentally, Patagonian squid has
declined in southern rockhopper penguin diets. However, southern
rockhopper penguin diets have shifted to notothenid fish, a prey that
has higher nutritional value than squid and that has become more
common. It is not certain whether squid abundance or fish abundance is
driving the switch. Bingham (1998, p. 6) reported that there is no
direct evidence that food availability has been affected by commercial
fishing, but both he and Putz et al. (2003b, p. 143) drew attention to
the need for careful monitoring of southern rockhopper penguin prey
availability in the face of commercial fisheries development.
The winter foraging range of southern rockhopper penguins breeding
at the Falkland Islands takes them into the area of longline fishing at
Burdwood Bank and onto the northern Patagonian shelf. Birds are not in
direct competition for fish prey species there. The risk of bycatch
from longline fishing is not a threat to penguins, as it is to other
seabird species, and on the northern Patagonian shelf where jigging is
the primary fishing method, bycatch is not a significant threat (Putz
et al. 2002, p. 282).
In our review of fisheries activities, we found no other reports of
documented fisheries interaction or possible competition for prey
between southern rockhopper penguins and commercial fisheries or of
documented fisheries bycatch in any other areas of the range of the
southern rockhopper penguin.
In summary, while fisheries activities have the potential to
compete for the prey of southern rockhopper penguins, we find that
there are adequate monitoring regimes and fisheries controls in place
to manage fisheries interactions with southern rockhopper penguins
throughout all of its range, and we have not reason to believe this
will change in the future.
Oil Spills
Oil development is a present and future activity in the range of
southern rockhopper penguins breeding at the Falkland Islands. A
favorite winter foraging area of southern rockhopper penguins is the
Puerto Deseado area along the coast of Argentina, which lies just to
the south of Commodoro Rivadavia, a major refinery and oil shipment
port. Oil pollution and ballast tank cleaning have been a significant
threat to Magellanic penguins (Spheniscus magellanicus) north of this
zone (Ellis et al. 1998, pp. 111-112). In 1986, 800 southern rockhopper
penguins were found dead near Puerto Deseado, to the south of Commodoro
Rivadavia, but consistent with trends for that year elsewhere in the
range, the birds appeared to have starved and there were no signs of
oiling (Ellis et al. 1998, p. 54). At the Falkland Islands, hydrocarbon
development is planned for areas north and southwest of the Falkland
Islands. As of 2002, oil-related activities in the Falkland Islands
were suspended, but exploration and production may start again in the
near future (Putz et al. 2002, p. 281). We have no information on
petroleum development in other areas of the southern rockhopper
penguin's range.
We recognize that an oil spill near a breeding colony could have
local effects on southern rockhopper penguin colonies now and in the
future. However, on the basis of the species' widespread distribution
and its robust population numbers, we believe the species can withstand
the potential impacts from oil spills. Therefore, we do not believe
that oiling or impacts from oil-related activities are factors
affecting the southern rockhopper penguin throughout all of its range
now or in the future.
On the basis of analysis of potential fisheries impacts and
possible impacts of petroleum development, we find that other natural
or manmade factors are not threats to the southern rockhopper penguin
in any portion of its range now or in the future.
Foreseeable Future
In considering the foreseeable future as it relates to the status
of the southern rockhopper penguin, we considered the stressors and
threats acting on the species. We considered the historical data to
identify any relevant existing trends that might allow for reliable
prediction of the future (in the form of extrapolating the trends). We
also considered whether we could reliably predict any future events
(not yet acting on the species and therefore not yet manifested in a
trend) that might affect the status of the species.
With respect to the southern rockhopper penguin, the available data
do not support a conclusion that there is a current overall trend in
population numbers, and the overall population numbers are high. As
discussed above in the five-factor analysis, we were also unable to
identify any significant trends affecting the species as a whole, with
[[Page 77273]]
respect to the stressors and threats we identified. There is no
evidence that any of the stressors or threats are growing in magnitude.
Thus, the foreseeable future includes consideration of the ongoing
effects of current stressors and threats at comparable levels.
There remains the question of whether we can reliably predict
future events (as opposed to ongoing trends) that will likely cause the
species to become endangered. As we discuss in the finding below, we
can reliably predict that changes to the marine environment will
continue to affect some southern rockhopper penguins in some areas, but
we have no reason to believe they will have overall population-level
impacts. Thus, the foreseeable future includes consideration of the
effects of such factors on the viability of the species.
Southern Rockhopper Penguin Finding Throughout Its Range
We identified a number of likely stressors to this species,
including: (1) Changes in the marine environment, (2) human use and
disturbance, (3) disease, (4) competition with fisheries, and (5) oil
spills. To determine whether these stressors individually or
collectively rise to a ``threat'' level such that the southern
rockhopper penguin is in danger of extinction throughout its range, or
likely to become so within the foreseeable future, we first considered
whether the stressors to the species were causing a long-term,
population-scale declines in penguin numbers, or were likely to do so
in the future.
Based on a tally of estimated numbers of southern rockhopper
penguins in each region of the species' range, there are approximately
1.4 million breeding pairs in the overall species' population. While
there have been major declines in penguin numbers in some areas,
particularly at the Falkland Islands and at Campbell Island and other
New Zealand islands, colonies in the major portion of the species'
range have experienced lesser declines, remained stable, or appear to
have increased. Therefore, based on the best available data, we do not
find an overall declining trend in the species' population. In other
words, the combined effects of the likely stressors are not causing an
overall long-term decline in the southern rockhopper penguin numbers.
Because there appears to be no ongoing long-term decline, the species
is neither endangered nor threatened due to factors causing ongoing
population declines, and the overall population of about 1.4 million
pairs or more appears robust.
We also considered whether any of the stressors began recently
enough that their effects are not yet manifested in a long-term decline
in species' population numbers, but are likely to have that effect in
the future. Given that the effects of stressors have either been
ameliorated (e.g., human use, competition with fisheries), or because
their effects appear to be restricted to a small portion of the
species' range, we do not believe their effects would be manifested in
overall population declines in the future. Therefore, the southern
rockhopper penguin is not threatened or endangered due to threats that
began recently enough that their effects are not yet manifested in a
long-term decline.
Next, we considered whether any of the stressors were likely to
increase within the foreseeable future, such that the species is likely
to become an endangered species in the foreseeable future. As discussed
above, we concluded that none of the stressors was likely to increase
significantly.
Having determined that a current or future declining trend does not
justify listing the southern rockhopper penguin, we next considered
whether the species met the definition of an endangered species or
threatened species on account of its present or likely future absolute
numbers. The total population of about 1.4 million pairs appears
robust. It is not so low that, despite our conclusion that there is no
ongoing decline, the species is at such risk from stochastic events
that it is currently in danger of extinction.
Finally, we considered whether, even if the size of the current
population makes the species viable, it is likely to become endangered
in the foreseeable future because stochastic events might reduce its
current numbers to the point where its viability would be in question.
Because of the wide distribution of this species, combined with its
high population numbers, even if a stochastic event were to occur
within the foreseeable future, negatively affecting this species, the
population would still be unlikely to be reduced to such a low level
that it would then be in danger of extinction.
Despite regional declines in numbers of southern rockhopper
penguins, the species has thus far maintained what appears to be high
population levels, while being subject to most if not all of the
current stressors. The best available information suggests that the
overall southern rockhopper penguin population is not declining,
despite regional changes in population numbers. Therefore, we conclude
that the southern rockhopper penguin is neither an endangered species
nor likely to become an endangered species in the foreseeable future
throughout all of its range.
Distinct Population Segment
Section 2(16) of the Act defines ``species'' to include ``any
distinct population segment of any species of vertebrate fish or
wildlife which interbreeds when mature.'' To interpret and implement
the DPS provisions of the Act and Congressional guidance, the Service
and National Marine Fisheries Service published a Policy regarding the
recognition of Distinct Vertebrate Population Segments in the Federal
Register (DPS Policy) on February 7, 1996 (61 FR 4722). Under the DPS
policy, three factors are considered in a decision concerning the
establishment and classification of a possible DPS. These are applied
similarly to endangered and threatened species. The first two factors--
discreteness of the population segment in relation to the remainder of
the taxon and the significance of the population segment to the taxon
to which it belongs--bear on whether the population segment is a valid
DPS. If a population meets both tests, it is a DPS, and then the third
factor is applied--the population segment's conservation status in
relation to the Act's standards for listing, delisting, or
reclassification (i.e., is the population segment endangered or
threatened).
Discreteness Analysis
Under the DPS policy, a population segment of a vertebrate taxon
may be considered discrete if it satisfies either of the following
conditions: (1) It is markedly separated from other populations of the
same taxon as a consequence of physical, physiological, ecological, or
behavioral factors (quantitative measures of genetic or morphological
discontinuity may provide evidence of this separation) or (2) it is
delimited by international 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 Act.
Southern Rockhopper penguins are widely dispersed throughout the
sub-Antarctic in colonies located on isolated island groups. With
respect to discreteness criterion 1, many of these areas are clearly
separated from others. Differences in physical appearance or plumage
patterns have been described between the nominate chrysocome type,
which breeds in the Falkland Islands and off the southern tip of South
[[Page 77274]]
America, and the eastern filholi type, which breeds in the Indian Ocean
and southwest Pacific south of Australia and New Zealand, but we are
unaware of further differences in physiological, ecological, or
behavioral factors among any groups within the overall range (Marchant
and Higgins 1990, p. 191). Among the prominent breeding areas of the
southern rockhopper penguin, we have identified two areas that may be
markedly separated from other populations of the same taxon or face
significant differences in conservation status from other southern
rockhopper populations: (1) The Falkland Islands, and (2) the islands
to the south of Australia and New Zealand, including Macquarie,
Campbell, Auckland, and Antipodes Islands, where southern rockhopper
penguins breed.
Falkland Islands: The southern rockhopper penguin breeds at about
52 locations around the Falkland Islands in aggregations numbering from
a few hundred to more than 95,000 nests or breeding pairs. The most
recent population estimates are of approximately 210,000 breeding pairs
(Kirkwood et al. 2007, p. 266). The Falkland Islands breeding sites are
separated from the nearest major southern rockhopper penguin breeding
concentrations at Staten Island, Argentina, by about 264 mi (425 km).
At Staten Island, there are reported to be 180,000 breeding pairs
(Schiavini 2000, p. 288). It is not known to what extent interbreeding
or movement of breeding pairs occurs between the Falkland Islands and
the extensive breeding colonies in southern Argentina and Chile,
although the possibility of movement of breeding birds from the
Falkland Islands to Staten Island has been suggested (Schiavini 2000,
p. 290).
Winter foraging studies show that the relatively short distance
between these colonies allows for interchange between the southern
rockhopper penguins at the Falkland Islands and those at the southern
tip of South America (Putz et al. 2006, p. 741). This overlap is by no
means complete; at least half of the breeding rockhopper penguins from
both the Falkland Islands and Staten Island forage in distinct winter
foraging areas that are not used by birds from the other region (Putz
et al. 2006, p. 741). However, in other areas there is extensive mixing
on the winter foraging grounds. For example, about 17 percent of the
birds from Staten Island foraged in the region of Burdwood Bank, an
isolated extension of the Patagonian continental shelf, due east of
Staten Island and due south of the Falkland Islands. About 25 percent
of the birds from the southern colonies on the Falkland Islands also
foraged in the Burdwood Bank region. Thus, Burdwood Bank is a foraging
area for some 90,000 breeding southern rockhopper penguins over the
winter period; about 31,000 originating from the Falklands and 60,000
from Staten Island. There is also mixing, although made up of a smaller
percentage of Falkland Islands birds (6 percent), in the winter
foraging areas along the northeastern coast of Tierra del Fuego.
While Falkland Islands colonies have historically been considered a
significant stronghold of the southern rockhopper penguin in the
southwestern Atlantic Ocean and declines there have been of significant
concern, recent research has identified major previously undocumented
colonies in the same region that are as significant, or more
significant, in abundance, and occupy portions of the same ecological
region. These include colonies at nearby Staten Island in Argentina and
at Ildefonso and Diego Ramirez Archipelagos in Chile, which are about
149 miles (240 km) further west. The overall southern rockhopper
penguin numbers in this region, including the Falkland Islands, total
about 765,000 breeding pairs (Kirkwood et al. 2007, p. 266), with
Falkland Islands colonies constituting 27 percent of this total. As
discussed above, extensive ecological overlap in foraging range between
Falkland Islands birds and the Staten Island colonies has been
documented, with overlap in use of the Burdwood Bank and some shared
foraging range on the Patagonian shelf. In turn, the foraging ranges of
Staten Island birds are likely to overlap with those of the Chilean
colonies to the west (Putz et al. 2006, p. 740). We find that the
literature increasingly refers to the biology and conservation of the
suite of colonies around the southern tip of South America and the
Falkland Islands as a significant larger regional concentration,
downplaying emphasis on the discreteness of the Falkland Islands
colonies (Kirkwood et al. 2007, p. 266; Putz et al. 2006, pp. 743-744;
Schiavini et al. 2000, p. 289). We concur with this conclusion;
therefore, we find that the Falkland Islands colonies of the southern
rockhopper penguin do not meet the criterion of discreteness for
determination of a DPS. On this basis, we do not consider the Falkland
Islands colonies of the southern rockhopper penguin to be a DPS.
New Zealand/Australia: With respect to the discreteness criterion
1, the southern rockhopper breeding islands south of New Zealand and
Australia are geographically isolated from southern rockhopper breeding
areas in the Indian Ocean and near the southern tip of South America,
with the closest colonies being roughly 7,300 km (4536 miles) at the
Heard and McDonald Islands.
Based on the large geographic distance between the populations
south of New Zealand and Australia from other populations, we conclude
that this segment of the population of the southern rockhopper penguin
passes the discreteness conditions for determination of a DPS.
Significance Analysis
If a population segment is considered discrete under one or more of
the conditions described in our DPS policy, its biological and
ecological significance is to be considered in light of Congressional
guidance that the authority to list DPSs be used ``sparingly'' while
encouraging the conservation of genetic diversity. In carrying out this
examination, we consider available scientific evidence of the
population segment's importance to the taxon to which it belongs. This
consideration may include, but is not limited to: (1) Its persistence
in an ecological setting unusual or unique for the taxon; (2) evidence
that its loss would result in a significant gap in the range of the
taxon; (3) evidence that it is 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 DPS differs
markedly from other populations of the species in its genetic
characteristics. A population segment needs to satisfy only one of
these criteria to be considered significant. Furthermore, the list of
criteria is not exhaustive; other criteria may be used, as appropriate.
Below, we consider the biological and ecological significance to the
New Zealand/Australia DPS.
Historical numbers of southern rockhopper penguins in this region
may have been as high as 960,000 breeding pairs, with declines recorded
from the New Zealand islands. Currently there are approximately 89,600-
101,500 breeding pairs in the region, which represents 6 to 7 percent
of the current estimated population of 1.4 million southern rockhopper
breeding pairs rangewide.
This group of breeding colonies inhabits a unique ecological and
geographical position in the range of the southern rockhopper penguin.
The underwater topography and oceanography of this area is unique and
has been described in detail in the Macquarie Island Management Plan
(Parks and Wildlife Service (Australia)
[[Page 77275]]
2006a, pp. 20-22). The islands sit in areas of relatively shallow
water, generally less than 3,280 ft (1,000 m) deep. Macquarie Island is
on the shallow Macquarie Ridge, which is associated with a deep trench
to the east, and connects to the north with the broader Campbell
Plateau, an extensive area of shallow water that is part of the
continental shelf extending southeast from New Zealand. The New Zealand
islands (Campbell, Auckland, and Antipodes), with breeding colonies of
southern rockhopper penguins, sit on the Campbell Plateau. This region
and all these islands sit just north of the Antarctic Polar Front Zone
(APFZ), a distinct hydrographic boundary with cold nutrient-rich
surface waters to the south and warmer, less rich, water to the north.
In addition, the Macquarie Ridge and Campbell Plateau form a major
obstruction to the ACC, which runs easterly at about 50[deg] S
latitude. This further increases the high degree of turbulence and
current variability in the area and is likely to directly or indirectly
encourage biological productivity (Parks and Wildlife Service
(Australia) 2006a, pp. 20-22).
We conclude that loss of the colonies in the region would create a
significant gap in the range of the taxon and remove southern
rockhopper penguins from the unique ecological setting of the Macquarie
Ridge and Campbell Plateau that lies in a unique position relative to
the APFZ and the ACC. Therefore, because we find the New Zealand/
Australia population segment to be discrete and because it meets the
significance criterion, with respect to (1) Its persistence in an
ecological setting unusual or unique for the taxon; and (2) evidence
that its loss would result in a significant gap in the range of the
taxon, it qualifies as a DPS under the Act.
New Zealand/Australia DPS Finding
Historical numbers of southern rockhopper penguins for this New
Zealand/Australia DPS may have been as high as 960,000 breeding pairs;
they are currently estimated at 89,600-101,500 breeding pairs.
Significant historical declines have been reported, in particular, at
Campbell Island, where a decline of 94 percent was recorded between the
early 1940s and 1985; at Antipodes Islands, where a decline of 94
percent was recorded; and at Auckland Islands, where the numbers halved
between 1983 and 1990. Current quantitative data is not available to
indicate whether, and to what extent, numbers throughout all of this
DPS continue to decline, but qualitative evidence indicates that
numbers at Campbell Island continue to decline. At Macquarie Island,
which represents 32 to 48 percent of this DPS, southern rockhopper
penguin numbers were recently estimated to be lower than previous
categorical estimates, but it is not clear whether this reflects a
decline versus more precise surveys.
As described in our five-factor analysis, changes to the marine
environment are cited as factors that have led to historic or recent
large declines at some, but not all, of the breeding locations within
the New Zealand/Australia DPS. While the oceanographic factors
contributing to such declines have not been clearly explained, they
appear to relate to changes in sea surface temperatures or to changes
in marine productivity at scales affecting individual colonies or
regions, leading to periodic or long-term reductions in food
availability. There is little or no current information, however, on
the effects of these changes on the breeding and foraging success of
southern rockhopper penguins in areas of previous decline. Although
changes in the marine environment appear to be affecting some southern
rockhopper breeding areas within this DPS, information is not at a
meaningful scale to evaluate current changes to the marine habitat in
the overall New Zealand/Australia DPS or to make predictions on future
trends about whether changes to the marine environment will affect
southern rockhoppers penguins across the New Zealand/Australia DPS.
Although the data indicate that changes to the marine habitat may
be a threat to New Zealand colonies on the Campbell Plateau, we do not
find that historical declines there are currently rising to the level
of having a significant effect on the entire DPS. Therefore, on the
basis of the best available scientific and commercial information, we
find that the present or threatened destruction, modification, or
curtailment of this species' marine habitat or range is not a threat to
the southern rockhopper penguin throughout the range of New Zealand/
Australia DPS, now or in the future. Below, we will further consider
whether the New Zealand colonies are a significant portion of the range
(SPR) of the DPS.
We have not documented any significant changes to the terrestrial
habitat of the southern rockhopper penguin. Also, on the basis of our
five-factor analysis, we did not find any of the other factors to be
threats to the southern rockhopper penguin's continued existence in any
portion of the species' range in the New Zealand/Australia DPS now or
in the future.
On the basis of our analysis of the best available scientific and
commercial information, we find that the southern rockhopper penguin is
not in danger of extinction throughout all of its range in the New
Zealand/Australia DPS or likely to become so in the foreseeable future
as a consequence of the threats evaluated under the five factors in the
Act.
Significant Portion of the Range Analysis
Having determined that the southern rockhopper penguin is not now
in danger of extinction throughout all of its range or in the New
Zealand/Australia DPS or likely to become so in the foreseeable future
as a consequence of the stressors evaluated under the five threat
factors in the Act, we also considered whether there were any
significant portions of its range where the species is in danger of
extinction or likely to become so in the foreseeable future.
The Act defines an endangered species as one ``in danger of
extinction throughout all or a significant portion of its range,'' and
a threatened species as one ``likely to become an endangered species
within the foreseeable future throughout all or a significant portion
of its range.'' The term ``significant portion of its range'' is not
defined by statute. For purposes of this finding, a significant portion
of a species' range is an area that is important to the conservation of
the species because it contributes meaningfully to the representation,
resiliency, or redundancy of the species.
The first step in determining whether a species is endangered in a
SPR is to identify any portions of the range of the species that
warrant further consideration. The range of a species can theoretically
be divided into portions in an infinite number of ways. However, there
is no purpose to analyzing portions of the range that are not
reasonably likely to be significant and endangered. To identify those
portions that warrant further consideration, we determine whether there
is substantial information indicating that (i) the portions may be
significant and (ii) the species may be in danger of extinction there.
In practice, a key part of this analysis is whether the threats are
geographically concentrated in some way. If the threats to the species
are essentially uniform throughout its range, no portion is likely to
warrant further consideration. Moreover, if any concentration of
threats applies only to portions of the range that are unimportant to
the conservation of the
[[Page 77276]]
species, such portions will not warrant further consideration.
If we identify any portions that warrant further consideration, we
then determine whether, in fact, the species is threatened or
endangered in any significant portion of its range. Depending on the
biology of the species, its range, and the threats it faces, it may be
more efficient for the Service to address the significance question
first, or the status question first. Thus, if the Service determines
that a portion of the range is not significant, the Service need not
determine whether the species is threatened or endangered there. If the
Service determines that the species is not threatened or endangered in
a portion of its range, the Service need not determine if that portion
is significant. If the Service determines that both a portion of the
range of a species is significant and the species is threatened or
endangered there, the Service will specify that portion of the range as
threatened or endangered pursuant to section 4(c)(1) of the Act.
The terms ``resiliency,'' ``redundancy,'' and ``representation''
are intended to be indicators of the conservation value of portions of
the range. Resiliency of a species allows the species to recover from
periodic disturbance. A species will likely be more resilient if large
populations exist in high-quality habitat that is distributed
throughout the range of the species in such a way as to capture the
environmental variability found within the range of the species. In
addition, the portion may contribute to resiliency for other reasons--
for instance, it may contain an important concentration of certain
types of habitat that are necessary for the species to carry out its
life-history functions, such as breeding, feeding, migration,
dispersal, or wintering. Redundancy of populations may be needed to
provide a margin of safety for the species to withstand catastrophic
events. This does not mean that any portion that provides redundancy is
a significant portion of the range of a species. The idea is to
conserve enough areas of the range such that random perturbations in
the system act on only a few populations. Therefore, each area must be
examined based on whether that area provides an increment of redundancy
important to the conservation of the species. Adequate representation
ensures that the species' adaptive capabilities are conserved.
Specifically, the portion should be evaluated to see how it contributes
to the genetic diversity of the species. The loss of genetically based
diversity may substantially reduce the ability of the species to
respond and adapt to future environmental changes. A peripheral
population may contribute meaningfully to representation if there is
evidence that it provides genetic diversity due to its location on the
margin of the species' habitat requirements.
To determine whether any portions of the range of the southern
rockhopper penguin warrant further consideration as possible threatened
or endangered significant portions of the range, we reviewed the entire
supporting record for the status review of this species with respect to
the geographic concentration of threats and the significance of
portions of the range to the conservation of the species. As previously
mentioned, we evaluated whether substantial information indicated that
(i) the portions may be significant and (ii) the species in that
portion may be currently in danger of extinction or likely to become so
within the foreseeable future. We have found that population declines
are uneven across the range, indicating the possible occurrence of
differential stressors or threats across the range of the southern
rockhopper penguin. On this basis we determined that some portions of
the southern rockhopper's range might warrant further consideration as
possible threatened or endangered significant portions of the range.
The southern rockhopper penguin is widely distributed throughout
the Southern Ocean. In our five-factor analysis we did not identify any
factor that was found to be a threat to the species throughout all of
its range or throughout all of the New Zealand/Australia DPS. In our
status review, we identified the Falkland Islands, Marion Island, and
finally, the Campbell Island Plateau region within the New Zealand/
Australia DPS as areas where declines have occurred, indicating the
possibility that the species may be threatened or endangered there.
Falkland Islands SPR Analysis
For the Falkland Islands, we first considered whether there is
substantial information to indicate that this portion of the range may
be in danger of extinction. The southern rockhopper penguin breeds at
about 52 locations around the Falkland Islands in aggregations
numbering from a few hundred to more than 95,000 nests or breeding
pairs. In the period from 1932-33 to 1995-96, the Falkland Islands
numbers declined from an estimated 1.5 million breeding pairs to
263,000 breeding pairs, or about 2.75 percent per year. However, since
that time numbers have been largely stable, fluctuating from 263,000
pairs in 1995-96 to a high of 272,000 breeding pairs in 2000-01 to
approximately 210,000 breeding pairs in 2005-06 (Kirkwood et al. 2007,
p. 266). It is unclear from available information whether numbers are
fluctuating or moving into another period of decline.
In summary, even though numbers of southern rockhopper penguins at
the Falkland Islands have shown an overall decline over time, numbers
have not declined at a consistent rate, but rather, there have been
periodic decreases in numbers, as well as at least one period of
increase. Therefore, we cannot assume a consistent rate of decline into
the future. Furthermore, it is unclear to what extent the fluctuations
in numbers are attributed to potential relocations to nearby Staten
Island, where numbers are stable to increasing. Numbers at the Falkland
Islands appear to be relatively high, at approximately 210,000 breeding
pairs, and in our five-factor analysis, we were unable to identify
ongoing threats to southern rockhopper penguin colonies at the Falkland
Islands.
Therefore, we have determined that the Falkland Islands portion of
the range does not satisfy one of the two initial tests, because there
is not substantial information to suggest that southern rockhopper
penguins in the Falkland Islands portion of the range may be currently
in danger of extinction, and since we cannot establish a continuing
declining trend in numbers or a continuing trend in threat factors, we
have no reason to believe that the species is likely to become
endangered there within the foreseeable future. Because we find that
the southern rockhopper penguin is not threatened or endangered in this
portion of the range, we need not address whether this portion of its
range is significant.
Marion Island SPR Analysis
For the Marion Island portion of the southern rockhopper penguin's
range, we first considered whether there is substantial information to
indicate that this portion of the range is significant. In terms of
abundance, Marion Island represents less than 5 percent of the overall
southern rockhopper penguin population, which is estimated at more that
1.4 million breeding pairs, with colonies widely distributed around the
Southern Ocean. Even not considering the breeding pairs at Marion
Island, the distribution of the species includes other large, stable or
increasing populations in high-quality habitat representing the
environmental variability found within the range of the species.
Therefore, even without the colonies at Marion Island, the species
would have sufficient resiliency to recover from periodic disturbances.
[[Page 77277]]
Furthermore, given the wide distribution of the species, even without
the colonies at Marion Island, the species would have sufficient
redundancy of other populations, such that random perturbations in the
system would only affect a few of the remaining populations. Finally,
not considering colonies at Marion Island, we find that the species has
adequate representation of its adaptive capabilities to enable the
species to adapt to future environmental changes. For example, the
number of southern rockhopper penguins at nearby Prince Edward Island
appears to have been stable since the 1980s with 35,000-45,000 pairs
present. Given Marion Island's position within the species' range
(i.e., far from the periphery of its range), and its proximity to other
southern rockhopper breeding areas, we do not believe the penguins at
Marion Island represent unique adaptive capabilities that would be lost
if their breeding colonies were lost from the population. Therefore, we
have determined that the Marion Island portion of the species' range
does not satisfy the significance test of being a significant portion
of the species' range, and we need not address whether this portion of
its range is threatened or endangered.
Campbell Plateau SPR Analysis
In our analysis of the New Zealand/Australia DPS of southern
rockhopper penguins, we identified major declines in numbers of
southern rockhopper penguins at the New Zealand breeding locations at
Campbell, Auckland, and Antipodes Islands, while numbers at Macquarie
Island are reported to be stable. As reflected in our five-factor
analysis, declines in penguin numbers at the locations identified above
are attributed to changes in the marine environment, which may have
affected overall marine productivity or the distribution and abundance
of southern rockhopper prey species at these sites. We view the New
Zealand Campbell Plateau colonies as an integral part of the geographic
area encompassed by the New Zealand/Australia DPS, and not as discrete
in and of itself. On this basis and on the basis of the severe declines
in this area, we will analyze the Campbell Plateau portion of the range
as a possible SPR.
With approximately 60,000 breeding pairs in the New Zealand range
of the southern rockhopper penguin, the three Campbell Plateau breeding
areas (Campbell, Auckland, and Antipodes Islands) make up over 60
percent of the New Zealand/Australia DPS and represent three out of its
four breeding concentrations. The presence of four breeding areas in
this DPS provides a measure of resiliency against periodic disturbance.
The loss of the Campbell Plateau breeding colonies would greatly reduce
the overall geographic range of this DPS to one location. The species
would no longer inhabit the ecologically distinct Campbell Plateau, an
area of historically high-quality habitat (as evidenced by previous
high numbers at Campbell Island). Loss of some or all of these three
breeding concentrations, two of which number less than 3,600 breeding
pairs, would significantly reduce the redundancy of populations in this
DPS and increase the impact of random or catastrophic perturbations on
remaining population numbers in the New Zealand/Australia DPS.
Therefore, we conclude that this Campbell Plateau portion of the range
passes the significance criterion for evaluating a SPR.
We next evaluate the Campbell Plateau portion of the range relative
to the geographical concentration of threats in this region. Among
colonies of southern rockhopper penguins throughout the species' range,
the three island groups within the Campbell Plateau portion of the
range have experienced the most severe declines. While trends are
unclear at Macquarie Island, overall numbers at Campbell Island are
recorded to have been as high as 800,000 breeding pairs in the early
1940s, and the last 1985 census numbers indicated a 94-percent
reduction to 51,500 pairs. Current qualitative information indicates
that colonies are still in decline, although the rate of that decline
is undocumented. In our analysis of the New Zealand/Australia DPS, we
concluded that changes to the marine environment that influence the
southern rockhopper penguin have affected the Campbell Plateau more
than the Macquarie Ridge region; therefore, the present or threatened
destruction, modification, or curtailment of its habitat or range is a
risk factor that threatens the southern rockhopper penguin in the
Campbell Plateau of the New Zealand/Australia DPS. On this basis, we
conclude that there is substantial information indicating that listing
of the Campbell Plateau portion of the range of the southern rockhopper
penguin as threatened or endangered may be warranted.
Having determined that the Campbell Plateau populations of the New
Zealand/Australia DPS of the southern rockhopper penguin are
significant and that there is substantial information indicating that
listing of this portion of the range as threatened or endangered may be
warranted, we will now summarize our analysis on whether listing of the
Campbell Plateau SPR is warranted.
Finding of Campbell Plateau SPR
Within the Campbell Plateau portion of the range of the southern
rockhopper penguin, significant historical declines have been reported,
in particular for Campbell Island where a decline of 94 percent was
recorded between the early 1940s and 1985. Continued unquantified
declines were reported to the present day. The most recent survey data
available from Campbell Island is from 1985, when there were 51,500
breeding pairs (Cunningham and Moors 1994, p. 34). At Antipodes
Islands, a decline of 94 percent was recorded between 1978 and 1995,
and current estimates are of 3,400 breeding pairs. At the Auckland
Islands, the number of penguins halved between 1983 and 1990 to 3,600
breeding pairs. There are no current quantitative data to indicate
whether, and to what extent, declines have continued at any of these
three island groups. Historical numbers of southern rockhopper penguins
in the Campbell Plateau portion of the species' range may have been as
high as 860,000 breeding pairs in the early 1940s; an overall decline
of 94 percent or more has brought this number down to less than 60,000
breeding pairs today. Given the low numbers at Antipodes and Auckland
Islands, Campbell Island is the primary stronghold for the Campbell
Plateau portion of the species' range.
In our five-factor analysis (see above), we did not find
documentation of any significant changes to the terrestrial habitat of
the southern rockhopper penguin. Changes to the marine environment,
however, are cited as factors that have led to historical or recent
large declines within the Campbell Plateau portion of the range. While
the oceanographic factors contributing to such declines have not been
clearly explained, they appear to relate to periodic or long-term
changes in sea surface temperatures within the summer or winter
foraging ranges of southern rockhopper penguins, or to changes in
marine productivity at scales affecting individual colonies or regions.
These oceanographic changes have apparently led to reductions in food
availability that may have occurred in short periods or extended over
periods of years. The available regulatory mechanisms have not
ameliorated the effects of these changes in the marine environment, and
we have no reason to believe these changes in the marine environment
will be ameliorated in the future; therefore, we find it reasonably
likely that the effects on the species in
[[Page 77278]]
this portion of its range will continue at current levels or
potentially increase. On the basis of the best available scientific and
commercial information and evidence of precipitous decreases of penguin
numbers in this area, we find that the present or threatened
destruction, modification, or curtailment of its marine habitat or
range is a threat to the southern rockhopper penguin in the Campbell
Plateau portion of its range now and in the future.
On the basis of our five-factor analysis of the best available
scientific and commercial information (see above), we find that
overutilization for commercial, recreational, scientific, or
educational purposes; disease; and predation are not threats to the
southern rockhopper penguin in the Campbell Plateau portion of its
range. On the basis of information on fisheries and oil development, we
find that other natural or manmade factors are not a threat to the
southern rockhopper penguin in the Campbell Plateau portion of its
range.
We find that precipitous population declines have depleted the
Campbell Plateau SPR to 6 percent of its prior abundance, and based on
our review of the best available information, we find it is reasonably
likely that these severe declines resulted from effects of changes in
the marine environment. We have no reason to believe that these changes
in the marine environment will not continue to affect southern
rockhopper penguins in the Campbell Plateau SPR at current (and
potentially greater) levels, further reducing population numbers.
Lower population numbers, a reasonably likely result in the
foreseeable future, would make this species even more vulnerable to the
threats from changes in the marine habitat, and would make the species
vulnerable to potential impacts from oil spills and other random
catastrophic events. Therefore, on the basis of our analysis of the
best available scientific and commercial information, we find that the
southern rockhopper penguin in the Campbell Plateau SPR of the New
Zealand/Australia DPS is likely to become endangered with extinction in
the foreseeable future.
Proposed Determination for the Southern Rockhopper Penguin in the
Campbell Plateau Portion of its Range
On the basis of analysis of the five factors and the best available
scientific and commercial information, find that listing the southern
rockhopper penguin as a threatened species in the Campbell Plateau
portion of its range under the Act is warranted. We, therefore, propose
to list the southern rockhopper penguin as a threatened species in the
Campbell Plateau portion of its range under the Act.
Final Determination for the Southern Rockhopper Penguin in All Other
Portions of its Range (i.e., not including the Campbell Plateau)
On the basis of analysis of the five factors and the best available
scientific and commercial information, we find that listing the
southern rockhopper penguin as threatened or endangered under the Act
throughout all or in any other portion of its range is not warranted.
Northern Rockhopper Penguin
Distribution
The northern rockhopper penguin (Eudyptes moseleyi) is restricted
to islands of the Tristan da Cunha region and Gough Island (St. Helena,
United Kingdom) in the South Atlantic and St. Paul and Amsterdam
Islands (French Southern Territories) in the Indian Ocean.
Two chicks banded at Amsterdam Island in 1992 were recovered off
the coast of eastern and southern Australia 7 and 9 months later,
indicating that immature Indian Ocean birds may winter off southern
Australia (Guinard et al. 1998, p. 224).
Population
The overall breeding population of northern rockhopper penguins is
estimated to be approximately 315,000-334,000 pairs on these island
groups in the South Atlantic and Indian Oceans and is thought to be
declining (Jouventin et al. 2006, p. 3,417; Guinard et al. 1998, p.
224; Woehler 1993, p. 58); however, based on the current information
available on population trends throughout the species' range, as
discussed below, the overall population trend of the northern
rockhopper penguin appears uncertain. Documentation of current trend
information is at this time only available for areas of Gough Island,
as discussed below, which is only part of the species' overall range.
South Atlantic Ocean
Gough Island
Early records indicate that numbers were historically in the
millions on both Gough Island and Tristan da Cunha. The most recent
population estimates indicate that over the past 45 years, numbers have
declined by about 96 percent on Gough Island, where there are currently
estimated to be 32,000-65,000 breeding pairs (Cuthbert in litt., as
cited in BirdLife International 2008a, pp. 2-3). Numbers on this island
are reported to have experienced large declines prior to the 1980s
(BirdLife International 2008a, p. 2), but were stable between 1982 and
2000 (Cuthbert and Sommer 2004, p. 101). Recent unpublished reports are
said to indicate recent substantial declines (Jouventin et al. 2006, p.
3,422); however, we have no further information on the regional extent
of decline, and so we cannot evaluate the effect of these declines on
the overall population status of the northern rockhopper penguin.
Tristan da Cunha
Tristan da Cunha consists of a main island and several smaller
islands. It is reported that the main island experienced a decline of
about 98 percent 130 years ago until about 30 years ago, but over the
past few decades numbers have been stable, with numbers currently
estimated at 3,200-4,500 breeding pairs (Cuthbert in litt., as cited in
BirdLife International 2008a, pp. 2-3.)
At Inaccessible Island, numbers may have declined ``modestly'' and
are currently estimated at 18,000-27,000 breeding pairs. Trends at
Nightingale and Middle Islands are poorly known, but recent
observations suggest local declines in the main colony on Nightingale
Island. The latest estimate of numbers of northern rockhopper penguins
on these two islands was in the 1970's and was reported to be 125,000
pairs (Cuthbert in litt., as cited in BirdLife International 2008a, p.
3). No information is available on numbers or trends at Stoltenhof
Island. In summary, given the numbers reported above, there appear to
be from 146,200-156,500 breeding pairs of northern rockhopper penguins
in the Tristan da Cunha Island group, not including those on
Stoltenhoff Island. Although numbers appear stable at Tristan, the main
island, trends are unknown throughout the remainder of this region.
Indian Ocean
Amsterdam Island
Northern rockhopper penguins at Amsterdam Island decreased in
numbers from 58,000 breeding pairs in 1971 to 24,890 in 1993, for an
overall decrease of 57 percent. The declines were most rapid, at 5.3
percent per year, between 1988 and 1993, but this was also a period
when there was the widest fluctuation in numbers, from a low of 17,400
to a high of 39,871 breeding pairs (Guinard et al. 1998, pp. 226-227).
After a lengthy period of gradual decline, the most recent available
data indicate a period of population fluctuation with
[[Page 77279]]
both increases (up to 39,871 breeding pairs from 17,400 pairs) and
decreases in numbers. With the final reported figure of 24,890, which
is above previous lows, best available data do not allow us to evaluate
if the colonies at Amsterdam Island continue to fluctuate, or are
stable, increasing, or declining.
St. Paul Island
At St. Paul Island, 50 mi (80 km) south of Amsterdam Island, the
numbers of northern rockhopper penguins increased by 56 percent over
the period of 1971-1993, with a current estimate of 9,000 breeding
pairs (Guinard et al. 1998, p. 227). This increase is considered to
have begun after the cessation of the use of rockhopper penguins as
bait in a crayfish industry, which operated in the 1930s, although all
the interrelationships acting on this gradual, upward trend are not
understood (Guinard et al. 1998, p. 227).
Other Status Classifications
The IUCN Red List classifies the northern rockhopper penguin as
`Endangered,' due to ``very rapid population decreases over the last
three generations (30 years) throughout its range.''
Summary of Factors Affecting the Species
Factor A: The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Terrestrial Habitat
We have found no current reports of threats to the terrestrial
breeding habitat of northern rockhopper penguins, and we have no reason
to believe threats to the terrestrial habitat will emerge in the
future.
Climate-Related Changes in the Marine Environment
With respect to the marine environment, Guinard et al. (1998, p.
224) reported that sea surface temperatures declined significantly,
approximately 1.4 [deg]F (0.8 [deg]C), around Amsterdam and St. Paul
Islands between 1982 and 1993. The annual mean decrease correlated with
declines in numbers of northern rockhopper penguins at Amsterdam Island
in the same period. Summer (February) sea surface temperatures were
also correlated with the numbers of northern rockhopper penguins at
Amsterdam Island the following spring. However, there was no
relationship between spring temperatures and the numbers of penguins at
Amsterdam Island, and there were no significant correlations between
sea surface temperatures and numbers at adjacent St. Paul Island, where
penguin numbers increased 56 percent during this same period. The
authors hypothesized that with cooling water temperatures, prey may
have shifted towards more northern waters, which are less accessible
for breeding penguins (Guinard et al. 1998, p. 227). Guinard et al.
(1998, p. 226) did not find major differences in breeding success
between the Amsterdam Island colony and study colonies in other areas.
The absence of conclusive correlations and the opposing trends
occurring at the two adjacent islands make it difficult to draw
conclusions relative to the impact of sea surface temperature changes
on northern rockhopper penguin marine habitat in these areas.
We have identified no reports of apparent marine habitat changes
for northern rockhopper penguins at Gough Island and Tristan da Cunha,
or reports of declines in the prey base in these areas.
Conclusion
Although it is possible that climate change will result in changes
to the marine habitat of the northern rockhopper penguin, data on the
relationship between sea surface temperature and other oceanic
conditions are ambiguous and not sufficient to draw conclusions as to
the contribution of changes in these conditions to the local declines
at Amsterdam Island. This precludes us from being able to identify
current relationships or to predict possible future trends.
Therefore, on the basis of the best available scientific and
commercial information, we find that the present or threatened
destruction, modification, or curtailment of this species' terrestrial
and marine habitats or range is not a threat to the northern rockhopper
penguin in any portion of its range now and we do not foresee that it
will become so in the future.
Factor B: Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
Use as Bait
Northern rockhopper penguins at the small colonies at St. Paul
Island in the Indian Ocean were exploited heavily for bait to support a
crayfish fishery in the 1930s, but this practice has been discontinued
since the 1940s (Guinard 1998, p. 227), and we have no reason to
believe it will recommence in the future.
In the Tristan da Cunha region, driftnet fishing and penguin use
for bait is reported to have caused significant mortality in the past.
Such activities are now prohibited and regarded as unlikely to return
(BirdLife International 2007, p. 3).
Harvest of Eggs
In the South Atlantic, the United Kingdom Department for
Environment, Food and Rural Affairs (DEFRA) reported that harvesting of
many seabirds, including northern rockhopper penguins, was intensive in
the past, but is now greatly reduced, and restricted to egg collection
for traditional domestic use of the 269 residents of Tristan da Cunha.
Under the 2006 Conservation Ordinance, egg collection is restricted to
Nightingale (25,000 breeding pairs), Stoltenhof and Middle Islands
(100,000 breeding pairs) in the Tristan da Cunha group (DEFRA 2007, p.
2; Tristan da Cunha Website 2008, p. 1). Rockhopper penguins lay two
eggs, the first of which often fails during incubation. If the chick
from the first egg hatches, this chick usually dies or is discarded as
the parents raise the larger chick from the second egg. If the second
egg fails to hatch or is lost, the chick from the first egg may survive
(Marchant and Higgins 1990, p. 190); therefore, this information
suggests that limited harvest of eggs for traditional domestic use can
be conducted without influencing breeding success of the large colonies
where collection occurs. However, we cannot evaluate whether this is
true because: (1) Empirical data are not available to verify whether
breeding success is affected by this practice; (2) population trends,
which would be a partial indicator of population status, on these
islands are unknown; and (3) since the restrictions on egg harvest were
only recently adopted in 2006, there may not have been sufficient time
to for the adopted restrictions on egg collection to have exhibited
their affects on population growth. Nevertheless, given that northern
rockhopper penguin numbers in the Tristan da Cunha region are estimated
at 146,200-156,500 breeding pairs, we do not find over-harvest of eggs
to be a threat to the species. Furthermore, we have no reason to
believe that the level of egg harvest will increase in the future.
Collection of Penguins From the Wild
The United Kingdom permitted a one-time harvest of 146 live
northern rockhopper penguins from Tristan da Cunha for exports to zoos
in the autumn of 2003 (DEFRA 2007, p. 2). Under the 2006 Conservation
Ordinance, no take, capture, removal, or collection of any native
organism is allowed without a permit (Tristan da Cunha Website 2008,
[[Page 77280]]
p. 1). Any take of live penguins from the wild would reduce numbers,
potentially acting as stressor to local colonies. However, given the
large numbers of breeding pairs (146,200-156,500) in this region and
the new (2006) regulations restricting take from the wild, we do not
consider the current level of limited take of individuals from the wild
to be a threat to this species. We have no reason to believe that the
level of collection of individuals from the wild will increase in the
future.
Scientific Research
Scientists studying northern rockhopper penguins at Amsterdam
Islands applied flipper bands to all incubating birds in a study colony
of from 100-300 breeding pairs. They reported that the mean adult
survival rate of 72 percent was significantly lower in the first year
after banding than in subsequent years (mean adult survival of 84
percent) suggesting that there was an effect of banding on the birds.
There was a similar effect for banded chicks (Guinard et al. 1998, p.
223-224). Based on this information, we believe that bird banding acts
as a stressor on northern rockhopper penguins in this region; however,
given the small size of the study colony and the relatively small
decrease in survival of a small number of birds, we conclude that the
bird banding practice as described in the literature is not a threat to
the northern rockhopper penguins at the Amsterdam Islands or elsewhere
in the species' range. There is no information that suggests banding
activities will increase in magnitude in any portion of the species'
range in the future.
Conclusion
We conclude that the primary utilization of northern rockhopper
penguins at this time in the Tristan da Cunha region is the regulated
collection of eggs for traditional domestic consumption by the small
number of residents, as well as regulated collection of individuals
from the wild. Although there may have been insufficient time since
regulations were put in place, to determine whether the current levels
of egg and animal collection are acting as stressors on the species in
this area, we believe that with the recent regulations in place, the
effects of these activities on the species in this area have likely
been reduced since 2006, and we expect that any as of yet unobserved
effects of the regulations would result in positive effects on the
conservation of the species. We have no reason to believe these
collection and harvest activities will increase over the current
levels. We do not have documentation of current population trends on
the islands where egg collection is occurring, but given that the
numbers in the Tristan da Cunha region are estimated at 146,200-156,500
breeding pairs, we do not find over-harvest of eggs, nor over-
collection of individuals to be a threat to the species.
Based on the available information, the only other utilization of
the species within its range that we were able identify is banding of
individuals for scientific research at Amsterdam Island. As discussed
above, we do not consider this activity a threat to the species now or
in the future.
On the basis of this information, we find that overutilization for
commercial, recreational, scientific, or educational purposes is not a
threat to the northern rockhopper penguin in any portion of its range
now or in the future.
Factor C: Disease or Predation
Disease
We are aware of no reports in the literature on the effect of
disease on northern rockhopper penguins anywhere within the species'
range, and we have no information to suggest that disease incidence or
transmission to the northern rockhopper penguin will increase in the
future. Therefore, we find that disease is not a threat to the northern
rockhopper penguin in any portion of the species' range now or in the
future.
Predation by Sub-Antarctic Fur Seals
Predation by sub-Antarctic fur seals has been identified as a
possible stressor on northern rockhopper penguins at Amsterdam Island,
where numbers of fur seals increased from 4,868-35,028 between the
1970s and 1982 (Guinard et al. 1998, p. 227). This increase in fur seal
numbers occurred within the time period (1971-1993) that northern
rockhopper penguin numbers at Amsterdam Island reportedly declined by
57 percent. Fur seal numbers subsequently leveled off through the mid-
1990s. It is reported that fur seals occasionally hunt and prey upon
rockhopper penguins, and Guinard et al. (1998, p. 227) concluded that,
even if penguins represent a minor part of the fur seal diet, the
increase in predation could be contributing to the declines of northern
rockhopper penguins observed at Amsterdam Island. The researchers
indicated that further study is needed to evaluate the effect of fur
seals on rockhopper penguins.
We acknowledge that fur seal predation has the potential to reduce
numbers of northern rockhopper penguins; however, as of yet the extent
of predation and its effect on the northern rockhopper penguin
population has not been determined. Furthermore, because fur seal
numbers have leveled off, we do not believe the possibility of
predation on northern rockhopper penguins will increase in the future.
Although the population trend at Amsterdam Island is unknown, according
to the best available information, there are an estimated 24,890
breeding pairs there, which is above previously low numbers.
There is no information to suggest that predation from fur seals is
or will become a threat to the northern rockhopper penguin in any other
portion of its range in the future.
Therefore we find that predation by fur seals is not a threat to
the northern rockhopper penguin in any portion of its range now or in
the future.
Introduced Predators
Rats were eradicated from St. Paul Island in 1999 (Terres Australes
and Antarctiques Francaises (TAAF) 2008, p. 3). At Gough Island, Jones
et al. (2003, p. 81) reported on the presence of mice (Mus musculus),
but did not indicate any effect on northern rockhopper penguin
colonies. There is no information available that suggests predation is
a threat to northern rockhopper penguins in any other portion of its
range and no reason to believe predation will become a threat to this
species in any portion of its range in the future.
Factor D: The Inadequacy of Existing Regulatory Mechanisms
Northern rockhopper penguins are protected from human over-
exploitation at the Tristan da Cunha area. Activities involving take of
the species, specifically harvest of eggs for domestic use by the small
community at Tristan da Cunha Island has been greatly reduced and
restricted (BirdLife International 2007, p. 4; DEFRA 2007, p. 2;
Tristan da Cunha Web site 2008, p. 1). Gough Island Wildlife Reserve is
a Natural World Heritage site and was first protected under the Tristan
da Cunha Wildlife Protection Ordinance in 1950. Inaccessible Island,
also in the Tristan da Cunha group, was given protection under the
Wildlife Protection Ordinance in 1997 and added to the Gough Island
Wildlife Reserve World Heritage site in 2004 (UNEP WCMC 2008d, pp. 1-2;
Ellis et al. 1998, p. 57).
Amsterdam Island was included in the French Antarctic National Park
(Parc National Antarctique Francais) in 1938 (World Wildlife Fund and
M. McGinley 2007, p. 4). Extensive restoration efforts
[[Page 77281]]
are underway at both Amsterdam and St. Paul Islands to restore native
flora, control introduced predators and, in particular, to protect and
restore the habitat of the endemic Amsterdam albatross (Diomedea
amsterdamensis) (World Wildlife Fund and M. McGinley 2007, p. 4).
Regular monitoring of northern rockhopper penguins is reported to
be taking place at Tristan da Cunha, and Gough, Amsterdam, and St. Paul
Islands (Birdlife International 2007, p. 4).
The literature reviewed has not highlighted any current
deficiencies in regulatory protection (Ellis et al. 1998, p. 57;
BirdLife International 2007, p. 4), and we have no reason to believe
the existing regulatory mechanisms will be reduced or will be less
effective in the future. Therefore, on the basis of the information
before us, we find that the existing regulatory mechanisms regarding
the conservation of northern rockhopper penguins are adequate now and
in the future throughout all or any portion of the species' range.
Factor E: Other Natural or Manmade Factors Affecting the Continued
Existence of the Species
Competition With Fisheries
We have found no information documenting competition for prey with
fisheries. Reports of possible bycatch from driftnet fishing are
identified as having occurred in the past and not likely to recur
(BirdLife International 2007, p. 3). BirdLife International (2008a, p.
4) suggests that northern rockhopper penguin food supplies may be
affected by squid fisheries, but we have no supporting information to
evaluate this factor as potential threat now or in the future.
Oil pollution is a possible concern for northern rockhopper
penguins, but we have no information to conclude that this rises to the
level of a threat for this species (Ellis et al. 2007, p. 5) now or in
the future.
Therefore, we find that other natural or manmade factors are not a
threat to the northern rockhopper penguin throughout all or any portion
of its range now or in the future.
Foreseeable Future
In considering the foreseeable future as it relates to the status
of the northern rockhopper penguin, we considered the stressors acting
on the species. We considered the historical data to identify any
relevant existing trends that might allow for reliable prediction of
the future (in the form of extrapolating the trends). We also
considered whether we could reliably predict any future events (not yet
acting on the species and therefore not yet manifested in a trend) that
might affect the status of the species.
With respect to the northern rockhopper penguin, the available data
do not support a conclusion that there is a current overall trend in
population numbers although the evidence suggests that there may have
been significant declines in the past, and the overall population
numbers are high. As discussed above in the five-factor analysis, we
were also unable to identify any significant trends with respect to the
stressors we identified. There is no evidence that any of the stressors
are growing in magnitude. Although we believe that recent restrictions
on egg collection and take from the wild may manifest itself in the
future in a positive manner with respect to trends, with respect to the
foreseeable future, we have considered the ongoing effects of current
stressors at comparable levels.
There remains the question of whether we can reliably predict
future events (as opposed to ongoing trends) that will likely cause the
species to become endangered. As we discuss in the finding below, we
acknowledge that periodic take from the wild and predation by fur seals
may continue to reduce local numbers in some northern rockhopper
penguin colonies, but we have no reason to believe they will have
population-level impacts. We also acknowledge that restricted egg
collection for traditional use and penguin banding activities may
affect reproductive success in some colonies; however, we have no
reason to believe these activities will have population-level impacts.
Thus, the foreseeable future includes consideration of the effects of
these factors on the viability of the northern rockhopper penguin.
Northern Rockhopper Penguin Finding Throughout Its Range
We identified a number of likely stressors to this species,
including traditional egg harvest, take of individuals from the wild,
bird banding associated with research activities, and predation by fur
seals. To determine whether stressors individually or collectively rise
to a ``threat'' level such that the northern rockhopper penguin is in
danger of extinction throughout its range, or likely to become so
within the foreseeable future, we first considered whether the
stressors to the species were causing a long-term, population-scale
decline in penguin numbers, or were likely to do so in the future.
As discussed above, the overall northern rockhopper population is
estimated at 315,000-334,000 breeding pairs. Although this species
declined severely in numbers over a large portion of its range, these
long-term, large-scale declines appear to have ended due to the
amelioration of historical threats: (1) Northern rockhopper penguin
exploitation for use as bait at St. Paul Island ended in the 1940s, and
the species' numbers there subsequently increased by 56 percent; (2)
driftnet fishing and penguin use for bait in the Tristan da Cunha
region is now prohibited; (3) fisheries bycatch has been reduced or
eliminated; (4) egg collection at Tristan da Cunha has been restricted
to traditional use for the small local population and has been
restricted to certain areas since 2006; and (5) take of individuals
from the wild at Tristan da Cunha has also been limited by regulation
since 2006. Currently, the only recent documented declines are on Gough
Island, which only represents 10 to 20 percent of the overall northern
rockhopper population, but information is not available on the scope of
the declines on Gough Island. We also do not know if local declines on
Gough Island are being offset by increases in other areas. Because
there appears to be no ongoing long-term decline, the species is
neither endangered nor threatened due to factors causing ongoing
population declines, and the overall population of 315,000-334,000
breeding pairs appears robust.
We also considered whether any of the stressors began recently
enough that their effects are not yet manifested in a long-term
decline, but are likely to have that effect in the future. The small,
periodic decrease in numbers due to take from the wild is immediately
reflected in population trends. Declines associated with fur seal
predation began in the early 1970s, and since fur seal numbers leveled
off through the 1990s, there has been sufficient time for the effect on
population numbers to be reflected in population trends. The limited
number of bird-banding activities has been demonstrated to manifest
their effects on reproductive success the year subsequent to the
banding activities. Any lag times associated with egg collection are
unknown, but since this activity has been severely restricted, we
expect any as of yet unobserved effects to be in the positive
direction. Therefore, the northern rockhopper penguin is not threatened
or endangered due to threats that began recently enough that their
effects are not yet manifested in a long-term decline.
Next, we considered whether any of the stressors were likely to
increase within the foreseeable future, such that the species is likely
to become an
[[Page 77282]]
endangered species in the foreseeable future. As discussed above, we
concluded that none of the stressors were likely to increase
significantly.
Having determined that a current or future declining trend does not
justify listing the northern rockhopper penguin, we next considered
whether the species met the definition of an endangered species or
threatened species on account of its present or likely future absolute
numbers. The total population of approximately 315,000-334,000 breeding
pairs appears robust. It is not so low that, despite our conclusion
that there is no ongoing decline, the species is at such risk from
stochastic events that it is currently in danger of extinction.
Finally, we considered whether, even if the size of the current
population makes the species viable, it is likely to become endangered
in the foreseeable future because stochastic events might reduce its
current numbers to the point where its viability would be in question.
Because of the wide distribution of this species, combined with its
high population numbers, even if a stochastic event were to occur
within the foreseeable future, negatively affecting this species, the
population would still be unlikely to be reduced to such a low level
that it would then be in danger of extinction.
The best available information suggests that the historical long-
term, large-scale population declines have ended, largely due to an
amelioration of historical threats to the species. Therefore, we
conclude that the northern rockhopper penguin is neither an endangered
species nor likely to become an endangered species in the foreseeable
future throughout all of its range.
Distinct Population Segment
A discussion of distinct population segments and the Service policy
can be found above in the southern rockhopper penguin Distinct
Population Segment section.
We are not aware of any information that would lead us to conclude
that the northern rockhopper penguin is comprised of population
segments that are either discrete or significant. Therefore, we have
not analyzed the northern rockhopper penguin under the Service's DPS
policy.
Significant Portion of the Range Analysis
Having determined that the northern rockhopper penguin is not now
in danger of extinction throughout all of its range or likely to become
so in the foreseeable future as a consequence of the stressors
evaluated under the five factors in the Act, we also considered whether
there were any significant portions of its range where the species is
in danger of extinction or likely to become so in the foreseeable
future. See our analysis for southern rockhopper penguin for how we
make this determination.
The northern rockhopper penguin is found in two primary areas of
the South Atlantic and Indian Oceans. In our five-factor analysis, we
did not identify any factor that was found to be a threat to the
species throughout its range. In our status review, we identified Gough
Island, Tristan da Cunha, and Amsterdam Island as areas where declines
have occurred, indicating the possibility that the species may be
threatened or endangered there.
Gough Island
The most recent population estimates indicate that over the past 45
years, numbers have declined by about 96 percent on Gough Island, where
there are currently estimated to be 32,000-65,000 breeding pairs
(Cuthbert in litt., as cited in BirdLife International 2008a, p. 2-3).
Numbers on this island are reported to have experienced large declines
prior to the 1980s (BirdLife International 2008a, p. 2), but were
stable between 1982 and 2000 (Cuthbert and Sommer 2004, p. 101).
Although recent unpublished reports are said to indicate recent
substantial declines on Gough Island (Jouventin et al. 2006, p. 3,422),
more detailed information on these declines is not currently available.
Therefore, we cannot assess the regional extent in the declines or the
magnitude of the decline. This precludes us from being able to evaluate
the overall trend in numbers at Gough Island, and given the recent
emergence of the reported decline, we are not able to predict if the
decrease in numbers will continue into the future. We have not
identified any threat to the species in this area, nor do we have
reason to believe this will change within the foreseeable future.
Therefore, we find that the northern rockhopper penguin is not
threatened or endangered in this portion of its range, and we
consequently need not address the question of significance.
Tristan da Cunha
It is reported that from 130 years ago until about 30 years ago the
main island of Tristan experienced a decline of about 98 percent.
However, since numbers have been stable for the past few decades, there
is currently no ongoing long-term decline there. At Inaccessible
Island, numbers are reported to have possibly declined ``modestly,''
but the limited information on the basis of this suggestion does not
allow a sufficient analysis of trends in this area. Trends at
Nightingale and Middle Islands are, likewise, poorly known, and no
information is available for trends at Stoltenhof Island. In summary,
given the numbers reported above, there appear to be from 146,200-
156,500 breeding pairs of northern rockhopper penguins in the Tristan
da Cunha Island group, not including those on Stoltenhof Island.
Numbers appear stable at Tristan, the main island, but since trends are
unknown throughout the remainder of this region, we are unable to
establish an overall trend for the region.
Based on our five-factor analysis, we found that the known
historical threats to this species in this region have been
ameliorated: (1) Driftnet fishing and penguin use for bait is now
prohibited; (2) fisheries bycatch has been reduced or eliminated; (3)
egg collection has been restricted to traditional use for the small
local population and has been restricted to certain areas since 2006;
and (4) take of individuals from the wild has also been limited by
regulation since 2006. In our five-factor analysis, we were unable to
identify any current threats to the species in this area, and we have
no reason to believe this will change in the future. Therefore, we find
that the northern rockhopper penguin is not threatened or endangered in
this portion of its range, and we consequently need not address the
question of significance.
Amsterdam Island
The overall numbers at Amsterdam Island declined 57 percent between
1971, when there were 58,000 pairs, and 1993, when there were 24,890
pairs. During the last period from 1988-1993, the numbers fluctuated
widely. For the years that survey data are available--in 1988, there
were 39,871 pairs (69 percent of the 1971 estimate); in 1990, there
were 30,000 pairs (51 percent); in 1991, there were 17,400 pairs (30
percent); in 1992, there were 35,000 pairs (60 percent); and in 1993,
there were 24,890 pairs (43 percent). Given the wide fluctuations in
this period, with both increases and decreases in numbers, with the
last year of data above the lowest figure recorded, it is not possible
to conclude that an overall declining trend has continued after this
period. The wide fluctuations in this period and the ability of numbers
of breeding pairs to rebound by 100 percent between two breeding
seasons suggest that observed numbers at breeding colonies during years
of low numbers in 1991 and perhaps in 1993
[[Page 77283]]
are not representative of the actual abundance in these years. There
have been no survey data at Amsterdam Island for the past 15 years, and
given the wide fluctuations during the last period of surveys, we
cannot reliably predict a future population trend. The most recent
population estimate of 24,890 breeding pairs is above previously low
numbers, and based on our five-factor analysis, we have not identified
any threat to the species in this area, nor do we have reason to
believe this will change in the future. Therefore, we find that the
northern rockhopper penguin is not threatened or endangered in this
portion of its range, and we consequently need not address the question
of significance.
Final Determination for the Northern Rockhopper Penguin
On the basis of analysis of the five factors and the best available
scientific and commercial information, we find that listing the
northern rockhopper penguin as threatened or endangered under the Act
in all or any significant portion of its range is not warranted.
Macaroni Penguin
Background
Biology
The macaroni penguin (Eudyptes chrysolophus) is a large, yellow-
crested, black-and-white penguin that inhabits sub-Antarctic islands
from the tip of South America eastwards to the Indian Ocean (BirdLife
International 2007, p. 1). It breeds in 16 colonies at 50 sites in:
Southern Chile, Falkland Islands, South Georgia and the South Sandwich
Islands, South Orkney and South Shetland Islands, Bouvet Island, Prince
Edward and Marion Islands, Crozet Islands, Kerguelen Islands, Heard and
MacDonald Islands, and locally on the Antarctic Peninsula (Woehler
1993, pp. 52-56; BirdLife International 2007, pp. 2-3).
Breeding colonies range in size from a few breeding pairs to large
colonies of up to 180,000 breeding pairs or more (Crawford et al. 2003,
p. 478; Trathan et al. 2006, p. 242). For example, at South Georgia
Island in the South Atlantic, there are approximately 17 main breeding
aggregations, ranging in size from 1,000 breeding pairs at Sheathbill
Bay to 2,560,000 breeding pairs at the Willis Islands (Trathan et al.
2006, p. 241; Trathan et al. 1998, p. 266). Within these larger
locations are individual colonies. For example, at Bird Island, the
Fairy Point colony has about 500-600 pairs, Goldcrest Point colony has
43,811 pairs, and Macaroni Cwm colony has about 10,000 breeding pairs
(Trathan et al. 2006, p. 242). In 2000-01 at Marion Island in the
southwestern Indian Ocean, about 53 colonies were distributed around
the entire perimeter of the 12 x 7 mi (19 x 12 km) island. Colonies at
Marion Island range in size from a few breeding pairs to two large
colonies of 143,000 and 186,812 breeding pairs, respectively (Crawford
et al. 2003, p. 478).
The basic life history of macaroni penguins at breeding sites has
been well-described, and there is reported to be little variation in
the breeding biology of the members of the genus Eudyptes as a whole
(Crawford et al. 2003, pp. 477-482). At both South Georgia and Marion
Islands, after spending the winter at sea from May to September,
breeding birds arrive at the colony synchronously in mid-October.
During pre-breeding, incubation, and chick-brooding, the adults fast
for long periods ashore, alternating with long periods at sea. At
Marion Island, incubation was 35 days; chicks gathered into
cr[egrave]ches at 23-25 days and fledged at 60 days around the third
week of February (Crawford et al. 2003, p. 482). After abandoning the
chicks, the adults leave the colony to feed and then return to molt
before leaving the colonies for the winter. Age at first breeding at
Marion Island is 2-3 years (Crawford et al. 2003, p. 482).
Given its large numbers and its widespread distribution, the
macaroni penguin is considered to be one of the most abundant bird
consumers of Antarctic krill (Euphausia superba). In global terms, the
species is considered to be one of the most important avian predators,
possibly consuming more food than any other seabird species (Trathan et
al. 2006, pp. 239-240 ; Brooke 2004, p. 248).
Feeding habits studies have identified a variety of prey species
consumed by macaroni penguins. At Marion Island, they were found to
feed on crustaceans, mainly a decapod shrimp (Nauticaris marionis),
euphausids (krill) (Euphaudia vallenti and Thyssanoessa vicina), and
amphipods (Themisto gaudichaudii) (Crawford et al. 2003, p. 484). At
South Georgia Island, the primary mass of the diet of macaroni penguins
was found to contain krill (Euphausia superba (Antarctic krill) and
Thysanoessa sp.), decapod shrimp (Chorismus antarcticus), and amphipods
(Themisto gaudichaudii), as well as a number of cephalopod and fish
species (Croxall et al. 1999, p. 128).
Macaroni penguins leave their colonies to forage at sea during the
breeding season. At South Georgia Island, they forage in waters bathed
by the ACC, which transports krill to the region from the waters around
the western Antarctic Peninsula and the Scotia Sea (Trathan et al.
2003, p. 569; Trathan et al. 2006, p. 240; Reid and Croxall 2001, p.
382; Fraser and Hoffman 2003, p. 13). During the winter the birds leave
the colonies, reportedly foraging widely north of the Antarctic
Convergence and have been reported from the waters of Australia, New
Zealand, southern Brazil, Tristan da Cunha, and South Africa (Shirihai
2002, p. 77).
The range of adults foraging at sea during ``brood guard'' (a
portion of the chick provisioning stage--the period when males stay
ashore to guard the chicks) is very tightly constrained, with females
making limited duration foraging trips lasting about 12 hours (Trathan
et al. 2006, p. 240). At South Georgia Island, females, when leaving
the individual colonies, swim in straight lines along colony-specific
trajectories toward predictable prey aggregations at the edge of the
continental shelf. If prey is encountered before they reach the shelf
edge, they stop and feed until they either return to the colony or move
farther offshore to find more prey (Trathan et al. 2006, p. 248). In
moving in predictable directions offshore during all parts of the chick
provisioning stage, penguins move towards waters influenced by the
southern ACC front, an area where krill abundance has been shown to be
generally higher (Trathan et al. 2006, p. 249; Trathan et al. 2003, pp.
577, 579). These studies illustrate the importance of the southern ACC
front in transporting krill from the region of the Antarctic Peninsula
to the waters of South Georgia Island (Trathan et al. 2006, p. 240;
Reid and Croxall 2001, p. 380).
Population
In 1993, the worldwide population of macaroni penguins was
estimated at 11.8 million pairs (Woehler 1993, p. 52). Current
estimates place the total population at 9 million pairs (BirdLife
International 2007, p. 2; Ellis et al. 2007, p. 5; Ellis et al. 1998,
p. 60), although due to potential underestimates in the South Georgia
Island region (see South Atlantic Ocean discussion below), this
estimate is, therefore, also likely to be an underestimate of the
overall population size.
South Atlantic Ocean
In 1980, there were approximately 5.4 million pairs 25
to 50 percent, (Woehler 1993, pp. 3, 55) of macaroni penguins at South
Georgia Island, yielding a range of 2.7-8.1 million pairs. At that same
location, the current estimates are 2.5-2.7 million
[[Page 77284]]
pairs (BirdLife International 2007, p. 3; DEFRA 2007, p. 2). The
current estimate, however, is likely to be an underestimate as it is
based on extrapolations of counts in smaller areas to predict numbers
in larger areas--an estimation technique of questionable use in this
species (for example, at the Prince Edward Islands in the Indian Ocean,
extrapolations of declining trends at small study colonies to estimates
of overall trends for the overall island were not supported by
empirical data; declines at larger colonies were much less significant
than those at small colonies (Crawford et al. 2003, p. 485)).
At South Georgia Island, the current overall number was
extrapolated from bird counts at a selected number of colonies that had
declined by 50 percent over the last 2 decades of the 20th century
(BirdLife International 2007, p. 3; Trathan et al. 2006, pp. 249-250).
The conclusion that the overall South Georgia numbers had halved during
that same time period has not been empirically verified in the
literature (Trathan et al. 1998, p. 265; Trathan and Croxall 2004, p.
125; Trathan et al. 2006, pp. 249-250; Trathan 2004, p. 342).
Furthermore, given the large variability in the 1980s estimate (2.7-8.1
million pairs) combined with the likely underestimate of current
numbers at South Georgia Island (2.5-2.7 million pairs), we cannot
reliably determine that there has been any decline in overall
population numbers at South Georgia Island, nor can we reliably predict
a declining population trend in the future.
South of the large concentrations of macaroni penguins at South
Georgia Island, there are small colonies scattered locally around South
Shetland Islands (about 7,080 total pairs), South Orkney Islands (about
50 pairs), and South Sandwich Islands (about 3,000 pairs), and a pair
reported on the Antarctic Peninsula (Woehler 1993, p. 54-55; BirdLife
International 2007, p. 3).
In the southeast Atlantic Ocean at Bouvet Island (Norwegian
Territory), there were some 100,000 breeding pairs in the 1960s and
early 1970s, but these are reported to have ``subsequently decreased''
but there is no current estimate (BirdLife International 2007, p. 3;
Woehler 1993, p. 52).
Macaroni penguins also breed in small colonies in approximately 8
island sites around the southern tip of South America in southern Chile
with abundance totaling up to 75,000 pairs and are reported to be
stable (Woehler 1993, p. 56; BirdLife International 2007, p. 4).
Indian Ocean
In the Prince Edward Islands (South African Territory), there are
about 300,000 pairs reported at Marion Island and 9,000 pairs at Prince
Edward Island (Crawford and Cooper 2003, p. 417; Crawford 2007, p. 9).
At Marion Island, there was a decline from 434,000 pairs in 1994-95 to
356,000 pairs in 2002-03, but given the magnitude of the population
numbers, this 18-percent decline over the 8-year time period is not
considered to be a significant change in the population (Crawford et
al. 2003, p. 485). In the three subsequent breeding years (2003-06)
small fluctuations between 350,000 and 300,000 pairs were observed
(Crawford 2007, p. 9).
On a local scale at Marion Island, significant declines in three
small study colonies (each under 1,000 pairs) have been reported,
although the extent of the declines is questionable. Monitoring of
these colonies between 1979-80 and 2002-03 indicated a cumulative
decrease in numbers by 88 percent (Crawford et al. 2003, p. 485);
however, changes in survey methodology, as explained below, limit the
comparability of the survey data, calling into question actual changes
in population numbers. While Crawford et al. (2003, p. 485) and
Crawford (2007, p. 9) reported that the total number of breeding pairs
in these colonies (comprising 9 to 20 percent of the total breeding
numbers at Marion Island) decreased by 60 percent from 1994-95 to 2002-
03, after a long period of relative stability, a sudden drop in numbers
appeared at the same time as an apparent shift in the investigators'
survey or tallying methodology (Crawford et al. 2003, p. 478). Despite
the declines reported, breeding success increased from 1995-96 to 2004-
05 in study colonies (Crawford et al. 2003, p. 484).
At Prince Edward Island, which has a fraction of the macaroni
penguins of its neighboring Marion Island, numbers declined from
approximately 17,000 pairs in 1976-77 to an estimated 9,000 pairs in
2001-02 (Crawford et al. 2003, p. 483). According to the more current
information provided here, the current IUCN figures overestimate the
percentage decline of the macaroni penguin at the Prince Edward Islands
(BirdLife International 2007, p. 3). Summing the figures provided above
on overall population declines at Marion and Prince Edward Islands, we
calculate the total decline for the two islands to be approximately 32
percent since 1979, instead of the 50 percent reported.
Moving eastward in the southern Indian Ocean, Woehler (1993, p. 52;
BirdLife International 2007, p. 4) reported up to 2 million breeding
pairs at the Crozet Island. Farther east at the Kerguelen Islands,
there are reported to be about 1.8 million pairs of macaroni penguin,
with a reported increase of 1 percent per year between 1962 and 1985,
and 1998 data indicate colonies are stable or increasing (BirdLife
International 2007, p. 4).
The Heard and McDonald Islands south of the Kerguelen Islands are
reported to have about 1 million breeding pairs each (Birdlife
International 2007, p. 3; Woehler 1993, p. 53). There are no reports of
trends.
Other Status Classifications
The macaroni penguin is categorized as `Vulnerable' by IUCN
Criteria because ``overall a majority of the world population appears
to have decreased by at least 30 percent over 36 years (three
generations).'' However, it is noted that this ``classification relies
heavily on extrapolation from small-scale data, and large-scale surveys
are needed to confirm the categorization'' (BirdLife International
2007, p. 1).
Population Summary
Current estimates place the total population of macaroni penguins
at 9 million pairs (BirdLife International 2007, p. 2; Ellis et al.
2007, p. 5; Ellis et al. 1998, p. 60). Although penguin numbers appear
to have declined by about 32 percent in the Prince Edward Islands since
the late 1970s, this area represents only 3.4 percent of the overall
current macaroni penguin population. As described above, in other parts
of the species' range, trends are increasing, stable, or unknown due to
poor or scant data. Given the different population dynamics observed
throughout the range of the macaroni penguin, as described above, we
cannot reliably predict nor do we have reason to believe that the
overall population numbers will decline in the future.
Summary of Factors Affecting the Species
Factor A: The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
Terrestrial Habitat
We have found no current reports of threats to the terrestrial
breeding habitat of the macaroni penguin, and we have no reason to
believe threats to the terrestrial habitat will emerge in the future.
[[Page 77285]]
Reduced Prey Availability
Changes in the availability of prey to the macaroni penguin have
been hypothesized for declines observed in study colonies at Marion and
South Georgia Islands. Below, we discuss both the potential impacts of
low prey availability, as well as potential causes of reduced prey
availability, including interspecific competition and climate-related
changes in the marine environment. In Factor E, we discuss the
potential impacts of fisheries on prey availability.
At Marion Island, moderate decreases in macaroni penguin numbers
have been attributed to an altered availability of food (Crawford and
Cooper 2003, p. 417) based on changes in weight of returning birds
after a winter at sea and variations in mass of chicks at fledging
(Crawford et al. 2006, pp. 185-186), but there is currently
insufficient research evaluating the causes of declines at Marion
Island to draw science-based conclusions.
At South Georgia Island, researchers have looked in depth at the
foraging behavior and diet of macaroni penguins and other marine
predators and related them to interspecific competition, prey
switching, and changes in the overall food base. While krill is known
as the primary prey of the macaroni penguins, at South Georgia Island
study colonies, the percentage of krill in the diet at Bird Island
declined significantly from 1980-2000, particularly after 1995 (Reid
and Croxall 2001, p. 379). During this period, there was also a decline
in the small Bird Island study colony (Reid and Croxall 2001, p. 379).
The percentage of krill in the macaroni penguin diet was significantly
correlated to the density of krill in the region and was also directly
related to prey-switching by the penguins (Barlow et al. 2002, p. 211).
In 1984, for example, krill was abundant and comprised 95 percent of
the mass of prey in the diet of macaroni penguins studied at South
Georgia Island (Croxall et al. 1999, p. 115). However, in years when
krill abundance was reduced, as in 1994 when there was a four-fold
decrease in krill biomass from 1984, the penguins studied shifted their
diet to other prey species, including amphipods (63.2 percent of the
mass in the diet) and fish species (15 percent, in particular,
myctophids (Krefftichthys anderssonii) and channichthids
(Pseudochaenichthys georgianus)), while krill comprised only 13.1
percent of the diet (Croxall et al. 1999, p. 117). This prey-switching
behavior suggests that the macaroni penguin has some adaptability in
adjusting to temporary fluctuations in their preferred prey (krill).
Reduction of Prey Due to Competition
Barlow et al. (2002, pp. 205-213) examined whether the decreased
availability of krill for macaroni penguins at South Georgia Island is
a result of competition with the other major krill predator in the
region, the Antarctic fur seal. Study colonies of macaroni penguins
have declined at South Georgia Island over the past 2 decades (see
Population discussion above), while fur seal numbers have increased at
a very rapid rate since the 1950s. The fur seal has recovered from near
extinction in the first half of the 20th century (to 400,000 in 1972
and to more than 3 million individuals breeding at South Georgia Island
at the present day), and they have expanded their breeding range across
the northwest end of South Georgia Island (Barlow et al. 2002, p. 206).
These researchers found at the Bird Island study site that there was
substantial overlap in the foraging range of macaroni penguins and
Antarctic fur seals during the breeding season, and that the size and
nature of krill prey consumed were very similar. They were unable to
determine if the different population trajectories of the two species
during the same period reflected ``different and independent species-
specific responses to variation in krill availability, or whether (or
to what extent) they have been substantially influenced by direct
interspecific competition'' (Barlow et al. 2002, p. 211). Therefore,
although the researchers suggest there is a dynamic interaction that
currently favors Antarctic fur seals over macaroni penguins in the
study area, this suggestion is speculation because the empirical data
have not distinguished whether the penguins and fur seals each have
different and independent responses to the variation in krill
availability or, alternatively, whether the two species have been
influenced by being in direct competition with each other (i.e., the
research has not confirmed that competition is occurring). Furthermore,
given that the level of interspecific competition is uncertain, the
authors' prediction that competition will likely increase as fur seals
continue to increase (Barlow et al. 2002, p. 212) is also speculation.
With respect to changes in the krill abundance at South Georgia
Island, Reid and Croxall (2001, pp. 377-384) examined population
demographics of the krill prey in the diets of four marine predators
breeding at Bird Island--Antarctic fur seals, macaroni penguins, gentoo
penguins (Pygoscelis papua), and black-browed albatrosses (Thalassarche
melanphrys). For data averaged over the decade of the 1980s, the two
penguin species and the Antarctic fur seals were consistently consuming
the majority of their krill diet from the largest of three size classes
identified. For the decade of the 1990s, there was a change in all
three species toward consuming krill in the middle size class (Reid and
Croxall 2001, p. 380). At the same time, negative changes in the
reproductive performance of all four species were recorded. For
macaroni penguins in the colonies studied, arrival condition and
reproductive output declined significantly in the second decade after
stability in penguin numbers in those colonies in the 1980s. These
results suggest that in the 1980s the biomass of krill in the largest
size class was sufficient to support predator demand, but it was not in
the 1990s (Reid and Croxall 2001, p. 378).
Indices of reproductive output for macaroni penguins in study
colonies declined over the period from 1980-2000 (Reid and Croxall
2001, pp. 379-380). While it is difficult to separate the relative
contribution to this decline from interspecific competition versus
reduction of krill due to other reasons, macaroni penguins were found
to be unique among the four predator species studied because they were
able to compensate for low availability of krill by switching to other
prey (Reid and Croxall 2001, pp. 379, 381; Croxall et al. 1999, p.
117).
Reid and Croxall (2001, p. 383) concluded that the balance between
krill supply and predator demand altered substantially from 1980-2000.
They suggested that a combination of two factors: (1) Changes in the
krill population structure arriving from the Antarctic Peninsula source
region, and (2) increased predator-induced mortality on the larger size
classes of krill arriving in the region effectively removed the buffer
of krill abundance and increased ``the frequency of years where the
amount of krill is insufficient to support predator demand'' (Reid and
Croxall 2001, p. 383). They suggested that this buffer or ``krill
surplus'' noted in the 1980s may have dated from the time when whaling
severely reduced the numbers of great whales in the Southern Ocean.
This unusually high temporary biomass of krill might have supported a
higher biomass of predators, potentially resulting in artificially high
population numbers of certain predator species, such as macaroni
penguins. We acknowledge that the change in ecosystem dynamics could
lead to a
[[Page 77286]]
new predator-prey equilibrium, whereby, some species temporarily
decline in numbers. This possibility precludes our ability to reliable
extrapolate population trends into the future, as long as population
numbers are relatively high, as they are in the macaroni penguin.
Reduction of Prey Due to Climate-Related Changes in the Marine
Environment
Changes in climate could potentially impact aspects of the marine
environment such as sea surface temperatures or shifts in currents,
ultimately leading to changes in prey availability. Reid and Croxall
(2001, p. 377) hypothesized that changes in the Antarctic Peninsula
region could affect the recruitment of the Antarctic krill populations
that supply the South Georgia Island marine ecosystem. Reid et al.
(2002, p. 1) showed that the size structure of the local South Georgia
Island krill population tracked closely with krill-recruitment events
in the Elephant Island region at the northeastern tip of the Western
Antarctic Peninsula (WAP). Events at Elephant Island, in turn, have
been found to be coherent with events at the Peninsula itself (Fraser
and Hoffman 2003, p. 9).
Trathan et al. (2003, p. 581) concluded that physical data at the
spatial and temporal resolution necessary to identify possible
relationships between large-scale variability within the ACC and the
krill biomass at South Georgia Island are not available. They did note,
on a preliminary basis, that periods of high krill abundance (i.e.,
January 1992 and January 1998) were linked to unusually low sea surface
temperatures in the southern ACC front near South Georgia Island and
that periods of krill scarcity were linked to sea surface temperatures
in the upper 20 percent of recorded values (i.e., January 1991 and
January 1994) (Trathan et al. 2003, p. 581). In describing warm and
cold anomalies in the temperature of the southern ACC front, these
authors did not address the question of whether there are consistent
directional changes occurring in the temperature of this current
(Trathan et al. 2003, pp. 569-582).
Fraser and Hoffman (2003, pp. 1-15) reviewed the krill cycle and
the recruitment of krill and related them to cyclical patterns of sea-
ice extent at the WAP. In studies similar to those at South Georgia
Island, the authors examined data on krill size classes in the diet of
a different species, the Adelie penguin (Pygoscelis adeliae) near
Palmer Station on the WAP, and compared these data against cyclical
variability in sea-ice extent between 1973 and 1996. Analyses have
shown that WAP sea-ice extent exhibits 4- to 5-year cycles of high ice
years followed by several low-ice years. The cycles follow the
periodicity of the Antarctic Circumpolar Wave (a phenomenon of
interannual anomalies in the atmospheric pressure, wind stress, sea
surface temperature, and sea-ice extent over the Southern Ocean that
propagates eastward with a period of over 4-5 years and takes 8-10
years to circle the globe) (White and Peterson 1996, p. 699; Fraser and
Hoffman 2003, p. 8). At the WAP, Fraser and Hoffman (2003, p. 6)
identified the beginning of five cycles between the 1973-74 and 1996-97
field seasons, and tracked four complete cycles (two 4-year, one 5-
year, and one 6-year). They looked at trends in krill size classes
within the diet of Adelie penguins and found that years of high krill
recruitment followed years of maximum September (winter) sea-ice extent
(Fraser and Hoffman 2003, p. 6). In the years following high krill-
recruitment years, the Adelie penguin diet reflected the consumption of
larger and larger krill each year as the dominant large cohort grew,
through a 4-to 5-year period, until the next large krill-recruitment
year occurred.
The strong age classes produced in a good ice year become the core
spawning stock for the next cyclical sea-ice maximum, generally 4 or 5
years away, with smaller cohorts in the intervening years. Krill reach
the limit of their life span after 5 years, and this age class is
reduced from several years of predation and mortality. We have
discussed above the work of Fraser and Hoffman (2003, pp. 1-15), who
reviewed the krill cycle and the recruitment of krill and related them
to cyclical patterns of sea-ice extent at the WAP. Of significance to
the observed trends at South Georgia Island, a 6-year ice cycle
occurred between 1980 and 1986 (a gap unique in the contemporary WAP
sea-ice record), which had significant consequences for krill
recruitment (Fraser and Hoffman 2003, p. 12). This ``senescence event''
in which the large krill cohort originating from the 1980 sea-ice
maxima may have died before they could reproduce and contribute to the
next generation of recruits may have led to a loss of most of the
strong 1980-81 cohort and its reproductive potential (Fraser and
Hoffman 2003, p. 12). The authors suggested this may have had major
ecological consequences. Correspondingly, krill abundance was at its
lowest recorded levels at Elephant Island in 1990, at the time the lost
cohort would have been expected to spawn again and, at South Georgia
Island, krill predators, including macaroni penguins at study colonies,
began to decline significantly after being stable throughout the 1980s
(Fraser and Hoffman 2003, p. 13). The authors noted that two or more
closely spaced senescence events of this sort would have devastating
consequences on the structure and function of krill populations and the
ecosystems they support (Fraser and Hoffman 2003, p. 13).
The study of Trathan et al. (2003, p. 581) described 2 years of
``particularly high'' krill abundance and 2 years of ``particularly
low'' krill abundance during the 1990s. The study raises questions as
to the ability to generalize comparisons between the 1980s and 1990s to
the current period (2001 to the present), for which we currently have
little or no empirical data either for krill or macaroni penguin
abundance or reproductive output. The decadal analyses of krill
abundance and macaroni penguin reproductive output at study colonies at
South Georgia Island through the year 2000 (Reid and Croxall 2001, p.
377), and of krill response off the WAP to climate change, physical
forcing (e.g., shifts in current or temperature patterns), and
ecosystem response, suggest that the krill populations and the
ecosystems they inhabit have become more vulnerable to climate-induced
perturbations (Fraser and Hoffman 2003, p. 13) and that overall krill
abundance has declined significantly in the last few decades (Atkinson
et al. 2004, p. 101; Loeb et al. 1997, p. 897).
Conclusion for South Georgia Island
Significant changes in krill abundance and composition have been
documented in study colonies of macaroni penguins on South Georgia
Island during a period of decline (up to 50 percent) of macaroni
penguins in those colonies over the last 2 decades of the 20th century.
Although these declines have been associated with a variety of factors,
including: (1) Variations in the temperature of the ACC at South
Georgia Island (Trathan et al. 2003, p. 581) and cycles of sea-ice
extent at the WAP, which have affected krill recruitment (Fraser and
Hoffman 2003, p. 13), and (2) increases in numbers of Antarctic fur
seals, which share the same food, suggesting competition, not enough
information is known about these relationships to predict the
availability of krill to macaroni penguins in the future.
Despite concurrent declines in macaroni penguin numbers and
[[Page 77287]]
increases in fur seal numbers in certain areas of the South Georgia
region, studies have not confirmed that competition between the two
species is occurring. Therefore, we cannot make reliable predictions
about whether competition will occur in the foreseeable future, much
less to what extent it would affect the availability of krill to the
macaroni penguin.
Although it is possible that climate change will result in changes
within the ACC and krill biomass and/or the frequency or severity of
krill ``senescence events,'' potentially affecting the macaroni penguin
population in the South Georgia Island region, we do not have
sufficient physical data at the spatial and temporal resolution
necessary to identify or predict possible trends or relationships
between large-scale variability within the ACC, sea ice changes, and
potential changes in the krill biomass.
Aside from our inability to identify future trends related to krill
availability to the macaroni penguin at South Georgia Island, neither
do we have enough information on the adaptability of the macaroni
penguin to changing krill availability. For example we do not know the
extent of flexibility it has in: (1) Relying on a greater diversity of
prey species to satisfy its long-term biological needs; (2) altering
its foraging routes; or (3) moving its breeding locations closer to
more dependable food supplies.
Despite our inability to predict future trends with regard to
changes in prey availability to the macaroni penguin or its ability to
adapt to those potential changes, we do not believe that the changes in
food availability currently acting on the macaroni penguin population
at South Georgia Island are causing a long-term decline in this
population. Although numbers may have declined locally, these declines
could have been offset, at least to some extent, by increases elsewhere
within the South Georgia Island region, and the population continues to
survive there in large numbers.
Macaroni penguins at South Georgia Island appear to have some
ability to switch to different prey at times of low krill abundance.
Given its flexibility in switching to alternative prey species and the
estimated abundance of the macaroni penguin population at South Georgia
Island (2.5-2.7 million pairs, and likely greater due to potential
underestimates), we believe that this population can withstand
disturbances linked to the marine changes identified. Given the lack of
comprehensive survey data throughout the South Georgia Islands, we
cannot reliably predict, nor do we have reason to believe, that the
overall population numbers will decline in the future as a result of
the marine changes identified. Therefore, we find that the present or
threatened destruction, modification, or curtailment of the species'
marine habitat or range is not a threat to the macaroni penguin in the
South Georgia Island portion of its range now or in the foreseeable
future.
Conclusion for the Remainder of the Macaroni Penguin's Range
At Marion Island, moderate decreases in macaroni penguin numbers
have been attributed to an altered availability of food (Crawford and
Cooper 2003, p. 417), but there is currently insufficient research
evaluating the causes of declines at Marion Island to draw any
conclusions about the causes, much less make predictions about future
trends of prey availability in that area. There is no information
available suggesting that a reduction in prey availability is a threat
to the macaroni penguin in any other portion of the species' range.
Although penguin numbers appear to have declined by about 32
percent in the Prince Edward Islands since the late 1970s, this area
represents only 3.4 percent of the overall current macaroni penguin
population. As described above (see Population discussion), in other
parts of the species' range, trends are increasing, stable, or unknown
due to poor or scant data. Given the different population dynamics
observed throughout the remainder of the range of the macaroni penguin,
we cannot reliably predict nor do we have reason to believe that the
overall population numbers will decline in the future as a result of
marine changes. Therefore, we find that the present or threatened
destruction, modification, or curtailment of the species' marine
habitat or range is not a threat to the macaroni penguin in any other
portion of its range now or in the foreseeable future.
Factor B: Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
We are not aware of any overutilization for commercial,
recreational, scientific, or educational purposes that is a threat to
the macaroni penguin in any portion of its range (BirdLife
International 2007, pp. 1-3; Ellis et al. 1998, p. 61) now or in the
foreseeable future.
Factor C: Disease or Predation
No blood-borne parasites (haematozoa) were found in any of 89 blood
smears from macaroni penguins collected at Marion Island in 2001
(Crawford and Cooper 2003, p. 418). Although parasites and disease have
not been identified as stressors at this island or other areas of the
Prince Edward Islands, the potential susceptibility of sub-Antarctic
penguins to haematozoan vectors has been recognized, and so strict
measures have been put in place at the Prince Edward Islands to
minimize the possibility of introducing avian diseases. Therefore, we
do not have reason to believe that disease will become a threat at the
Prince Edward Islands in the foreseeable future. Disease has not been
identified as a threat to macaroni penguins in any other areas of the
species' range, nor do we have reason to believe disease will become a
threat in any portion of the species' range within the foreseeable
future. Therefore, we find that disease is not a threat to the macaroni
penguin in any portion of its range now or in the foreseeable future.
Predation has not been cited as a threat in macaroni penguins.
Although predation by feral cats has been reported on Kerguelen
Archipelago, remains of macaroni penguins were rarely found in scat
analyses from feral cats there (Pontier et al. 2002, p. 835), and the
rare exceptions could have been a result of scavenging on carcasses as
opposed to predation. There have been no reported local or large-scale
declines in macaroni penguin numbers at the Kerguelen Islands, and in
fact, there were reported increases in numbers there at a rate of 1
percent per year between 1962 and 1985. The 1998 data indicate colonies
are stable or increasing (BirdLife International 2007, p. 4). This
suggests that predation is not affecting the macaroni penguin numbers
there. There is no information available that suggests the number of
predators at the Kerguelen Islands will increase in the foreseeable
future or that the current potential predators will begin to affect
penguins in the foreseeable future. Therefore, we do not consider
predation to be a stressor, much less a threat to macaroni penguins on
the Kerguelen Archipelago. There is no information available that
suggests predation is a threat to macaroni penguins in any other
portion of its range, now, nor do we expect it to become a threat in
the foreseeable future.
Based on review of the best available scientific and commercial
information, we find that predation is not a threat to the macaroni
penguin in any portion of its range now or in the foreseeable future.
[[Page 77288]]
Factor D: The Inadequacy of Existing Regulatory Mechanisms
The macaroni penguin is widely distributed on largely uninhabited
islands in the territories of seven countries and the region under the
jurisdiction of the Antarctic Treaty and the Convention for the
Conservation of Antarctic Marine Living Resources (CCAMLR). Breeding
islands are largely inaccessible, access is tightly controlled, and
most of them are under protected status (BirdLife International 2007,
p. 4; Ellis et al. 1998, p. 61). South Georgia Island is administered
by the Government of South Georgia and South Sandwich Islands (GSGSSI).
Research on macaroni penguins in South Georgia, for example at Bird
Island, which is a Specially Protected Area under the South Georgia
Environmental Management Plan, is conducted by the British Antarctic
Survey under annual permits from the GSGSSI. Visitation to South
Georgia is tightly controlled with visitors' permits required prior to
visiting research sites (British Antarctic Survey 2008, p. 2). The
Australian islands of Heard and McDonald are also World Heritage sites
with limited or no visitation and with management plans in place (UNEP
WCMC 2008, p. 6). In 1995, the Prince Edward Islands Special Nature
Preserve was declared and accompanied by the adoption of a formal
management plan (Crawford and Cooper 2003, p. 420). In our analysis of
other factors, we determined that existing national regulatory
mechanisms are adequate regarding the conservation of macaroni penguins
throughout all or any portion of the species' range. (For example in
our discussion of Factor E, we consider the adequacy of CCAMLR in the
conservation and management of krill fisheries.) Furthermore, there is
no information available to suggest this will change within the
foreseeable future.
Factor E: Other Natural or Manmade Factors Affecting the Continued
Existence of the Species
Competition With Commercial Krill Fisheries
Another possible factor affecting krill abundance is commercial
krill fisheries. Krill fisheries have operated in the region of South
Georgia Island since the early 1980s and are managed by CCAMLR (Reid
and Croxall 2001, p. 383). Harvesting occurs in the winter around South
Georgia Island and moves south as the ice retreats in spring and
summer. Krill fisheries have harvested only a fraction of the approved
CCAMLR catch limits since 1993 (Croxall and Nichol 2004, p. 574). In
their analysis of predator response to changes in krill abundance, Reid
and Croxall (2001, p. 383) note that the fishery near South Georgia
Island is small and that total catches actually declined by almost 50
percent since 1980 for commercial reasons, rather than due to lack of
krill abundance. They do not cite competition with krill fisheries as a
contributor to macaroni penguin declines (Reid and Croxall 2001, p.
383); however, given that we have already identified the reduced
availability of krill as a stressor to the macaroni penguin (see Factor
A), we recognize that commercial krill fisheries have the potential to
contribute as one of several sources of this stressor. With respect to
the local macaroni penguin declines observed, Reid and Croxall (2001,
p. 383) note that the potential for competition with krill fisheries
should be taken into account in future CCAMLR krill management
strategies.
Croxall and Nicol (2004, pp. 570-574) reported on the ongoing
efforts within CCAMLR to improve management procedures for the krill
fishery in long-established fisheries areas and sub-areas in the
Southern Ocean. These included improving the overall estimation of
krill to redefine catch limits over large sectors of the Southern Ocean
(Croxall and Nicol 2004, p. 573). Also, out of concern that krill
management was being undertaken at a scale too large to prevent
localized depletion of the krill resource if the fishery was
concentrated in small proportions of a particular established area or
sub-area, CCAMLR adopted approaches to better manage the area
encompassing the Antarctic Peninsula, Scotia Sea, and South Georgia.
First, on the basis of the work of their scientific committee, the
CCAMLR Commission in 2002 formally adopted smaller and more
ecologically realistic management areas, referred to as Small-Scale
Management Units (SSMUs) to manage krill fishing at scales most
relevant to the natural environment--prey-predator interactions (Hewitt
et al. 2004, p. 84). This includes three SSMUs established in the South
Georgia region. At the same time, CCAMLR adopted precautionary catch
limits, well below the catch limits identified in global scale
analyses, to limit harvest in the fisheries areas while specific
protocols for dividing harvest among the SSMUs are being developed
(Hewitt et al. 2004, p. 84).
The process of establishing science-based approaches by which to
allocate harvest to the SSMUs was agreed by the CCAMLR commission and
is well underway. Allocation options have been developed (Hewitt et al.
2004, pp. 81-97); these are being evaluated in a series of meetings
that have taken place over the last 3 years; and by spring 2008, a
model will be developed to allocate catch limits (Trivelpiece 2008,
pers. comm.). This model will allow testing of different approaches to
allocating catch and lead to recommendations to the Scientific
Committee and the CCAMLR Commission (Hewitt et al. 2004, p. 84). This
work to establish decision rules includes assessing: (1) Spatial and
temporal use of the area by krill predators and fisheries; (2) fluxes
of krill into and out of the area; (3) competition between species; and
(4) how to manage these areas to respond to ecosystem change (Croxall
and Nicol 2004, p. 573). In support of development of allocation
approaches at the level of SSMUs, CCAMLR has already adopted a
requirement that krill catches be reported to very small geographical
detail (10 x 10 nm) and over small 10-day time scales (Hewitt et al.
2004, p. 84). Parallel efforts by the CCAMLR Ecosystem Monitoring
Program involve monitoring selected predator, prey, and environmental
indicators of ecosystem status to detect and record changes in critical
components of the ecosystem and distinguish the impacts of harvesting
from other environmental variability (Croxall and Nichol 2004, pp. 573-
574).
Conclusion for South Georgia Island
Based on: (1) The small size of krill fisheries in the region of
South Georgia Island, and (2) the ongoing efforts under CCAMLR to
sustainably manage krill species, efforts specifically designed to
investigate and respond to the phenomena described for the South
Georgia Island region (e.g., the setting of precautionary catch limits
designed to limit local impacts and the development and implementation
of SSMUs), we find that competition with krill fisheries is not a
threat to the macaroni penguin at South Georgia Island. Furthermore, we
have no reason to believe that the krill fisheries will expand in this
region in the foreseeable future or that the current management and
regulatory mechanisms will be weakened or become less effective in the
foreseeable future.
Conclusion for the Remainder of the Macaroni Penguin's Range
Given the ongoing efforts within CCAMLR to improve management
procedures for the krill fishery in long-established fisheries areas
and sub-areas in the Southern Ocean (Croxall and Nicol 2004, pp. 570-
574), including: (1) Efforts already completed to provide better
management of overall harvest
[[Page 77289]]
limits and the adoption of precautionary catch limits for smaller
management areas, and (2) the substantial progress being made in
bringing krill harvest management down to the scale of SSMUs, we find
that regulatory mechanisms for the management of krill fisheries are
adequate. We have no reason to believe that the current regulatory
mechanisms will be weakened or become less effective in the future. As
discussed above, management efforts even improved over the last several
years. Therefore, we find that competition with krill fisheries is not
a threat to the macaroni penguin in any other portion of its range now
or in the foreseeable future.
Oil Spills
The possibility of oil pollution is cited in reviews of the
conservation status of macaroni penguins (BirdLife International 2007,
p. 3; Ellis et al. 1998, p. 61). At Marion Island, oil spills have had
severe effects on penguins at landing beaches, but a new Prince Edward
Islands Management Plan, prepared by the Republic of South Africa, now
requires that utmost care be taken to avoid fuel spills during
transfers at the islands (Crawford and Cooper 2003, p. 418).
Oil and chemical spills can have direct effects on the macaroni
penguin in New Zealand waters, and based on previous incidents around
New Zealand, we consider this a stressor to this species. For example,
in March 2000, the fishing Vessel Seafresh 1 sank in Hanson Bay on the
east coast of Chatham Island and released 66 tons (60 tonnes (t)) of
diesel fuel. Rapid containment of the oil at this very remote location
prevented any wildlife casualties (New Zealand Wildlife Health Center
2007, p. 2). The same source reports that in 1998 the fishing vessel
Don Wong 529 ran aground at Breaksea Islets, off Stewart Island,
outside the range of the erect-crested penguin. Approximately 331 tons
(300 t) of marine diesel was spilled along with smaller amounts of
lubricating and waste oils. With favorable weather conditions and
establishment of triage response, no wildlife casualties of the
pollution event were discovered (Taylor 2000, p. 94). We are not aware
of reports of other oil spill incidents within the range of the
macaroni penguin.
We recognize that an oil spill near a breeding colony could have
local effects on macaroni penguin colonies. However, on the basis of
the species' widespread distribution around the remote islands of the
South Atlantic and southern Indian Oceans and its robust population
numbers, we believe the species can withstand the potential impacts
from oil spills. Also, given the remoteness of South Georgia Island,
its relatively high population numbers, and the measures in place to
control cruise vessel activities in the region, we believe the
population on South Georgia Island can withstand the potential impacts
from oil spills. Furthermore, we have no reason to believe that the
frequency or severity of oil spills in any portion of the species'
range will increase in the future or that containment capabilities will
be weakened. Therefore, we conclude that oil pollution from oil spills
is not a threat to the species in any portion of its range now or in
the foreseeable future.
Foreseeable Future
In considering the foreseeable future as it relates to the status
of the macaroni penguin, we considered the stressors acting on the
macaroni penguin. We considered the historical data to identify any
relevant existing trends that might allow for reliable prediction of
the future (in the form of extrapolating the trends). We also
considered whether we could reliably predict any future events (not yet
acting on the species and therefore not yet manifested in a trend) that
might affect the status of the species.
With respect to the macaroni penguin, the available data do not
support a conclusion that there is a current overall trend in
population numbers, and the overall population numbers are high. As
discussed above in the five-factor analysis, we were also unable to
identify any significant trends with respect to the stressors we
identified. There is no evidence that any of the stressors are growing
in magnitude. Thus, the foreseeable future includes consideration of
the ongoing effects of current stressors at comparable levels.
There remains the question of whether we can reliably predict
future events (as opposed to ongoing trends) that will likely cause the
species to become endangered. As we discuss in the finding below, we
can reliably predict that periodic declines in prey availability and
oil spills will continue to cause local declines in macaroni penguin
colonies, but we have no reason to believe they will have population-
level impacts. Thus, the foreseeable future includes consideration of
the effects of such crashes on the viability of the macaroni penguin.
Macaroni Penguin Finding Throughout Its Range
We identified a number of stressors to this species: (1) Reduced
prey (krill) availability due to (a) competition with Antarctic fur
seals, (b) changes in the marine environment, or (c) competition with
commercial krill fisheries; and (2) oil spills. To determine whether
these stressors individually or collectively rise to a ``threat'' level
such that the macaroni penguin is in danger of extinction throughout
its range, or likely to become so within the foreseeable future, we
first considered whether the stressors to the species were causing a
long-term, population-scale decline in penguin numbers, or were likely
to do so in the future.
As discussed above, the overall macaroni penguin population is
estimated at 9 million pairs (BirdLife International 2007, p. 2; Ellis
et al. 2007, p. 5; Ellis et al. 1998, p. 60) and is likely to be
greater due to likely underestimates at South Georgia Island. Although
penguin numbers appear to have declined by about 32 percent in the
Prince Edward Islands since the late 1970s, this area represents only
3.4 percent of the overall current macaroni penguin population. In
other parts of the species' range, trends are increasing, stable, or
unknown due to poor or scant data. Based on the best available data, we
conclude that the population is stable overall. In other words, the
combined effects of reduced prey availability, competition with
Antarctic fur seals, changes in the marine environment, competition
with commercial krill fisheries, and the impacts from oil spills at the
current levels are not causing a long-term decline in the macaroni
penguin population. Because there appears to be no ongoing long-term
decline, the species is neither endangered nor threatened due to
factors causing ongoing population declines, and the overall population
of 9 million pairs or more appears robust.
We also considered whether any of the stressors began recently
enough that their effects are not yet manifested in a long-term
decline, but are likely to have that effect in the future. There is
little data on macaroni penguin prey availability prior to the last 3
decades, and even less information on causes of prey decline. In any
case, the periodic declines in prey availability over the last 30 years
have had sufficient time to be reflected in population trends, and
there appears to be no overall trend, regardless of localized changes
in abundance. In addition, no oil spill events have occurred recently
enough
[[Page 77290]]
that the population effects would not yet be observed. Therefore, the
macaroni penguin is not threatened or endangered due to threats that
began recently enough that their effects are not yet manifested in a
long-term decline.
Next, we considered whether any of the stressors were likely to
increase within the foreseeable future, such that the species is likely
to become an endangered species in the foreseeable future. As discussed
above, we concluded that none of the stressors were likely to increase
significantly.
Having determined that a current or future declining trend does not
justify listing the macaroni penguin, we next considered whether the
species met the definition of an endangered species or threatened
species on account of its present or likely future absolute numbers.
The total population of approximately 9 million pairs or more appears
robust. It is not so low that, despite our conclusion that there is no
ongoing decline, the species is at such risk from stochastic events
that it is currently in danger of extinction.
Finally, we considered whether, even if the size of the current
population makes the species viable, it is likely to become endangered
in the foreseeable future because stochastic events might reduce its
current numbers to the point where its viability would be in question.
Because of the wide distribution of this species, combined with its
high population numbers (approximately 9 million pairs), even if a
stochastic event were to occur within the foreseeable future,
negatively affecting this species, the population would still be
unlikely to be reduced to such a low level that it would then be in
danger of extinction.
Despite local declines in numbers of macaroni penguins in some
colonies, the species has thus far maintained what appears to be high
population levels, while being subject to most if not all of the
current stressors. The best available information suggests that the
overall macaroni penguin population is stable, despite localized
changes in population numbers. Therefore, we conclude that the macaroni
penguin is neither an endangered species nor likely to become an
endangered species in the foreseeable future throughout all of its
range.
Distinct Population Segment
A discussion of distinct population segments and the Service policy
can be found above in the Distinct Population Segment section of the
southern rockhopper penguin finding.
Macaroni penguins are widely dispersed throughout the sub-Antarctic
in colonies located on isolated island groups. Among these groups, we
have identified two possible segments to evaluate for DPS status: (1)
The Prince Edward Islands, administered by South Africa, and (2) South
Georgia Island, administered by the United Kingdom. For both of these
areas, there may be differences in conservation status from other areas
of the range of the macaroni penguin. Based on the data available,
these are the only two areas where decreases in penguin numbers within
colonies have been documented. Throughout the remainder of the macaroni
penguin's range, population trends are for the most part unknown but in
limited cases reported as stable or increasing (see Population
discussion).
Discreteness Analysis
A discussion of discreteness can be found above in the southern
rockhopper penguin Discreteness Analysis section.
Prince Edward Islands: Considering the question of discreteness,
this island group is unique in the range of the macaroni penguin in
being administered by the Republic of South Africa. Numbers are
reported to have declined by approximately 18 percent at Marion Island
between 1983-84 and 2002-03 and 47 percent at nearby Prince Edward
Island in the same period for an overall 32-percent decline from about
451,000 to about 309,000 breeding pairs at the Prince Edward Islands.
Based on its delimitation by international boundaries and its
potentially different conservation status from other areas of abundance
of the macaroni penguin, we conclude that this segment of the
population of the macaroni penguin passes the discreteness conditions
for determination of a DPS.
South Georgia Island: At this island, which is administered by the
United Kingdom, macaroni penguin numbers at study colonies are reported
to have declined by 50 percent in the last two decades of the 20th
century. Based on its delimitation by international boundaries and its
potentially different conservation status from other areas of abundance
of the macaroni penguin, we conclude that this segment of the
population of the macaroni penguin passes the discreteness conditions
for determination of a DPS.
Significance Analysis
A discussion of significance can be found above in the southern
rockhopper penguin Significance Analysis section.
Prince Edward Islands: The current abundance of about 309,000
breeding pairs of macaroni penguins at the Prince Edwards Islands
represents 3 percent of the overall estimated population of macaroni
penguins worldwide and 6 percent of the estimated numbers in the Indian
Ocean. This does not provide a significant contribution globally to the
abundance of the taxon. The Prince Edward Islands are the westernmost
of one of four island groups that lie just north of the Antarctic
Convergence Zone and comprise the Indian Ocean breeding habitat of the
macaroni penguin. The Prince Edward Islands and the Crozet Islands sit
641 mi (1,066 km) apart in similar ecological settings, rising at about
46[deg] S at the western and eastern ends, respectively, of the shallow
Crozet Plateau. Both islands are adjacent to both the shallow waters of
the plateau and the deeper water areas to the south of this region.
Even though it is the westernmost breeding location in the Indian
Ocean, loss of the Prince Edward Islands colonies would not create a
significant gap in the range of the taxon. The Indian Ocean colonies
are already very isolated (1,581 mi (2,545 km)) from the closest
colonies to the west in the South Atlantic Ocean at Bouvet Island. The
distance between Bouvet Island and the Prince Edward Islands is 1,581
mi (2,545 km) and the distance between Bouvet Island and Crozet Island
is 2,135 mi (3,426 km). Loss of the Prince Edward Island population
would increase the distance between Indian Ocean breeding areas and
Bouvet Island by only 25 percent, or 554 mi (886 km). We do not have
data to evaluate whether interchange occurs between these South
Atlantic Ocean and Indian Ocean breeding colonies, so we do not know if
the 25-percent increase in the distance between these breeding areas is
significant. We also have no evidence that the Prince Edward Island
populations differ markedly from others in genetic characteristics. On
the basis of this information, we conclude that the Prince Edward
Island birds do not comprise a significant numerical contribution to
the overall population of macaroni penguins, they do not occupy an
unusual or unique ecological setting for the taxon, and their loss
would not result in a significant gap in the range of the taxon. This
population is not the only surviving natural occurrence of this
species, and it is not known to differ genetically from other
populations of the species. On this basis, the Prince Edward Islands
populations of the macaroni penguin are not significant to the taxon as
a whole and therefore do not constitute a DPS.
South Georgia Island: The current abundance of macaroni penguins at
South Georgia Island represents 28 percent of the global estimated
population and is the largest known concentration of breeding colonies
of
[[Page 77291]]
this species. For the South Atlantic region, the South Georgia Island
population segment represents the core of a range that includes areas
of abundance at the tip of South America and scattered small colonies
in the islands at the tip of the Antarctic Peninsula. We conclude that
loss of the colonies at South Georgia Island would create a significant
gap in the range of the taxon and remove macaroni penguins from the
unique ecological setting of South Georgia Island, which lies at the
downstream end of the flow of nutrients and krill carried by the ACC
from the vicinity of the Western Antarctic Peninsula. Therefore, we
conclude that the South Georgia Island population of the macaroni
penguin is significant to the taxon as a whole and qualifies as a
distinct population segment.
South Georgia Island DPS Finding
We identified a number of stressors to the South Georgia Island DPS
of the macaroni penguin: (1) Reduced prey (krill) availability due to
(a) competition with Antarctic fur seals, (b) changes in the marine
environment, or (c) competition with commercial krill fisheries; and
(2) oil spills. To determine whether these stressors individually or
collectively rise to a ``threat'' level such that the macaroni penguin
is in danger of extinction in the South Georgia Island DPS, or likely
to become so within the foreseeable future, we first considered whether
the stressors were causing a long-term, population-scale decline in the
DPS, or were likely to do so within the foreseeable future.
The macaroni penguin DPS at South Georgia Island is estimated to
include 2.5-2.7 million breeding pairs; however, as previously
discussed (see Population discussion) the current estimate is likely to
be an underestimate as it is based on extrapolations of counts in
smaller areas to predict numbers in larger areas--an estimation
technique of questionable use in this species. Although study colonies
within the South Georgia Island DPS have decreased steeply in numbers
(by 50 percent) over the period from 1980-2000, we do not know the
status of the remainder of the colonies throughout the DPS, and
therefore, do not know the overall population trend for the South
Georgia Island DPS. In a similar situation at the Prince Edward
Islands, the use of figures from censuses of small study colonies would
have led to a 100-percent overestimate of declines (i.e., an inferred
50-percent decline, would actually be a 25-percent decline) (Crawford
et al. 2003, p. 485). We also do not have information on whether the
reported declines have continued over the last decade.
In our five-factor analysis for the macaroni penguin, we found that
at South Georgia Island, reduced krill availability has been identified
as a stressor associated with local declines of up to 50 percent at
small study colonies over the last 2 decades of the 20th century. In
our assessment of this stressor, we were unable to reliably identify
the source of reduced krill availability to macaroni penguins in the
South Georgia Island DPS. We do not have sufficient information as to
the continued abundance of krill populations reaching the waters of
South Georgia Island, nor predictive capability related to the future
abundance of krill and other prey of the South Georgia DPS, to conclude
that prey shortages will lead to future declines. Under CCAMLR,
measures are being taken to monitor krill abundance and manage krill
fisheries, which are small in scale, at ecosystem scales relevant to
safeguarding prey for predator species at South Georgia, including the
macaroni penguin. At the same time, studies have shown that macaroni
penguins at South Georgia Island have some ability to compensate for
declines in krill by switching to alternative prey. This may provide a
means to mitigate, at least to some degree, against reproductive
failure in times of reduced krill abundance.
With respect to other factors, we are not aware of any
overutilization for commercial, recreational, scientific, or
educational purposes that is a threat to the South Georgia DPS, and,
based on review of the best available scientific and commercial
information, we find that neither disease nor predation is a threat to
the DPS. We find that regulatory mechanisms are adequate at South
Georgia Island now or in the foreseeable future. With respect to other
natural or manmade factors, we find that oil spills are not a threat to
the DPS now or in the foreseeable future.
In evaluating the impact of these factors, we have also considered
the size and trends of the South Georgia DPS of macaroni penguin.
Recognizing the highlighted uncertainties about the overall population
estimates for the South Georgia and the likelihood that these figures
are likely to be underestimates, the best available information
provided by the United Kingdom government indicates that there are
estimated to be 2.7 million pairs (DEFRA 2007, p. 2). The previous
estimate from 1980 has a large margin of error, which limits its use in
establishing trends--5.4 million pairs 25 to 50 percent,
(Woehler 1993, pp. 3, 55), yielding a range of 2.7-8.1 million pairs.
Based on the poor quality of this population information, we cannot
reliably establish an overall trend in the South Georgia Island DPS of
the macaroni penguin. Therefore, there is no reliable data that lead us
to believe that the combined effects of reduced prey availability,
competition with Antarctic fur seals, changes in the marine
environment, competition with commercial krill fisheries, and the
impacts from oil spills at the current levels are causing a long-term
decline in the South Georgia Island DPS of the macaroni penguin
population. Because we cannot establish an ongoing long-term decline,
this DPS is neither endangered nor threatened due to factors causing
ongoing population declines, and the overall population estimate of 2.7
million pairs appears robust.
We also considered whether any of the stressors acting on colonies
within the South Georgia DPS of the macaroni penguin began recently
enough that their effects are not yet manifested in a long-term
decline, but are likely to have that effect in the future. There is
little data on macaroni penguin prey availability in the South Georgia
region prior to the last 3 decades, and even less information on causes
of prey decline. In any case, the periodic declines in prey
availability over the last 30 years have had sufficient time to be
reflected in population trends, and there is no reliable evidence of an
overall population trend for the DPS, regardless of localized changes
in abundance. In addition, no oil spill events have occurred recently
enough that the population effects would not yet be observed.
Therefore, the macaroni penguin is not threatened or endangered in the
South Georgia Island DPS due to threats that began recently enough that
their effects are not yet manifested in a long-term decline.
Next, we considered whether any of the stressors were likely to
increase within the foreseeable future, such that the species is likely
to become an endangered species in the foreseeable future. As discussed
above, we concluded that within the South Georgia Island DPS, none of
the stressors were likely to increase significantly.
Having determined that a current or future declining trend does not
justify listing the South Georgia Island DPS of the macaroni penguin,
we next considered whether the species met the definition of an
endangered species or threatened species on account of its present or
likely future absolute numbers. The total macaroni penguin
[[Page 77292]]
population in the South Georgia Island DPS is estimated at 2.7 million
pairs, and appears robust. It is not so low that, despite our
conclusion that there is no ongoing decline, the population is at such
risk from stochastic events that it is currently in danger of
extinction.
Finally, we considered whether, even if the size of the current
population makes the species viable, it is likely to become endangered
in the foreseeable future because stochastic events might reduce its
current numbers to the point where its viability would be in question.
Because of the large number of dispersed breeding areas (17 main
breeding aggregations) throughout the South Georgia DPS, the large
number of individual colonies within these larger areas, and finally,
because of the large overall population size within the South Georgia
DPS, we believe that even if a stochastic event were to occur within
the foreseeable future, the population would still be unlikely to be
reduced to such a low level that it would then be in danger of
extinction.
Despite local declines in numbers of macaroni penguins in some
colonies within the South Georgia DPS, the population has thus far
maintained what appears to be high population levels, while being
subject to most if not all of the current stressors, and there is no
reliable information that shows an overall declining population trend
of the South Georgia DPS. Therefore, we conclude that the South Georgia
DPS of the macaroni penguin is neither an endangered species nor likely
to become an endangered species in the foreseeable future.
Significant Portion of the Range Analysis
Having determined that the macaroni penguin is not now in danger of
extinction or likely to become so in the foreseeable future throughout
all of its range or in the South Georgia DPS as a consequence of the
stressors evaluated under the five factors in the Act, we also
considered whether there were any significant portions of its range,
both within the South Georgia DPS, and within the remainder of the
species' range where the species is in danger of extinction or likely
to become so in the foreseeable future. See our analysis for southern
rockhopper penguin for how we make this determination.
The macaroni penguin is widely distributed throughout the Southern
Ocean. In our five-factor analysis, we did not identify any factor that
was found to be a threat to the species throughout its range or
throughout the South Georgia DPS.
SPR Analysis Within the South Georgia Island DPS
In an effort to determine whether this species is endangered or
threatened in a significant portion of the range of the South Georgia
Island DPS of the macaroni penguin, we first considered whether there
was any portion of this range where stressors were geographically
concentrated in some way. However, since we only have trend information
on a limited number of colonies with respect to both stressors and
population trends, we could not determine whether stressors were acting
differently in one portion of the range versus another. Therefore, we
were not able to identify any portions of the range within the South
Georgia Island DPS that warrant further consideration.
SPR Analysis Within the Remainder of the Macaroni Penguin's Range
In an effort to determine whether this species is endangered or
threatened in a significant portion of the remainder of the species'
range (i.e., anywhere within the species' range except the South
Georgia DPS), we first considered whether there was any portion of this
range where the species may be either endangered or threatened with
extinction. Declines have been reported in the Prince Edward Islands.
There was a decline from 451,000 pairs in 1983-84 to 356,000 pairs in
2002-03, but given the magnitude of the population numbers, this 18
percent decline over the 8-year time period is not considered to be a
significant change in the population (Crawford et al. 2003, p. 485). In
the three subsequent breeding years (2003-06) small fluctuations
between 350,000 and 300,000 pairs were observed (Crawford 2007, p. 9).
In our analysis, we found that the total decline has been approximately
32 percent since 1979. In our analysis of the five factors for the
macaroni penguin we identified no unique stressor affecting the Prince
Edward Islands populations. On the basis of its large population size
and limited declines (relative to overall population numbers) observed
over a period of 30 years, we conclude that there is not substantial
information that the Prince Edward Islands portion of the range may
currently be in danger of extinction or likely to become in danger of
extinction in the foreseeable future. Therefore this portion of the
range does not pass the test of endangerment for consideration as an
SPR.
Final Determination for the Macaroni Penguin
On the basis of analysis of the five factors and the best available
scientific and commercial information, we find that listing the
macaroni penguin as threatened or endangered under the Act in all or
any significant portion of its range or in the South Georgia DPS is not
warranted.
Emperor Penguin
Background
Biology
The emperor penguin (Aptenodytes forsteri) is the largest living
species of penguin. It is congeneric with the king penguin (Aptenodytes
patagonicus), but is double the size of this next largest penguin
species at 3-4 ft (1-1.3 m) in height and 44-90 lb (20-41 kg) in weight
(Shirihai 2002, pp. 57, 59). Emperor penguins generally feed over
continental shelf and continental margins of Antarctica, except for a
wide-ranging and relatively undocumented juvenile life stage. In
winter, they breed in colonies distributed widely along the sea ice
fringing the coast of Antarctica. In summer, during the molting period
when they must stay ashore, they depend on areas of stable pack ice or
nearshore, land-fast ice (Kooyman 2002, pp. 485-495; Kooyman et al.
2000, p. 269).
Life History
The life history of emperor penguins is unique among birds, with
breeding and incubation taking place in the Antarctic winter. Kooyman
(2002, pp. 485-495) summarizes this life history. Breeding birds arrive
in the colonies in April. After a period of courtship, egg-laying takes
place in mid-May. Male emperor penguins incubate the eggs through the
Antarctic winter until mid-July to early August. The females depart the
colony soon after egg-laying and forage at sea for 2 months. When the
females return, the males break their extensive winter fast. This fast
of 110-115 days has been documented to last from before courtship,
through incubation, and past the hatching of the chick (Kirkwood and
Robertson 1997, p. 156). However, unlike previous natural history
descriptions of emperor penguins, late fall transects have suggested
that at some of the largest colonies in the northern Ross Sea, where
open water is closely accessible in late fall, males and females may
feed after courtship and immediately before egg-laying, thus shortening
the fast and the energetic stress of incubation for males (Van Dan and
Kooyman 2004, p. 317). After the single egg hatches, the female emperor
penguin returns. At that point, the males and females begin to share
the feeding of the chick, coming and going on foraging trips away from
[[Page 77293]]
the colony throughout the late winter and spring. These foraging trips
last from 3 weeks to as little as 3 days, getting progressively shorter
as the spring advances (Kooyman 2002, pp. 485-495; Kooyman et al. 1996,
p. 397). The adults leave the colonies from mid-December to mid-January
on pre-molt foraging trips, which may take them up to 186 mi (300 km)
north of the continent and up to 745 mi (1,200 km) from the colony. By
late January to early February they arrive in areas where they can find
stable land-fast ice or pack ice to allow them to stay ashore for the
1-month molt (Kooyman et al. 2004, pp. 281-290; Wienecke et al. 2004,
pp. 83-91). Following the molt, they embark on post-molt foraging
trips, which bring breeding birds back to the colony in April.
The dispersal patterns of emperor penguin chicks after fledging are
poorly known. Once they leave the colonies they are seldom seen and do
not return again for several years. They return to the colony when 4
years old and breed the following year (Shirihai 2002, p. 61). Kooyman
et al. (1996, p. 397) followed the movements of five radio-tagged
juveniles at their departure from their colony at Cape Washington in
the Ross Sea. All traveled north beyond the Ross Sea to the Antarctic
Convergence, the boundary of the Southern Ocean, reaching 56.9[deg] S
latitude. While radio-signals were lost before the onset of winter,
Kooyman et al. (1996, p. 397) suggested that the birds may have
remained in the water north of the pack ice until at least June. He
noted that at this crucial period of their lives, juvenile emperor
penguins may be exposed to conditions similar to more northern penguin
species, for example, commercial fishing in the Southern Ocean. It is
hypothesized that juveniles ranging north from the Mawson Coast may
feed and compete with king penguins that are foraging south in the fall
and winter from their Indian Ocean breeding colonies.
Distribution
Emperor penguins breed on land-fast ice in colonies distributed
around the perimeter of the Antarctic continent from the western
Weddell Sea to the southwestern base of the Antarctic Peninsula
(Kooyman 2002, p. 490; Lea and Soper 2005, p. 60; Woehler 1993, pp. 5-
10;). For example, in the Ross Sea, six colonies are spaced 31-62 mi
(50-100 km) apart along the Victoria Land coast (Kooyman 1993, p. 143).
Looking at the reported data, we conclude that the total number of
historically or presently recorded colonies is approximately 45.
Woehler (1993, pp. 5-10) documented 42 reported colonies around the
continent, which included seven colonies discovered between 1979 and
1990 (Woehler 1993, p. 5). Colonies along Marie Byrd Land east of the
Ross Sea are few or undocumented, with only one confirmed, recently
discovered breeding colony at Siple Island (Lea and Soper 2005, pp. 59-
60) and one outlying small colony at the Dion Islands at the western
base of the Antarctic Peninsula (Woehler 1993, p. 9; Ainley et al.
2005, p. 177). At least three new locations have been discovered since
1990 (each with over 2,000 breeding pairs) and one other colony was
confirmed (Woehler and Croxall 1997, p. 44; Coria and Montalti 2000,
pp. 119-120; Lea and Soper 2005, pp. 59-60; Melick and Bremmers 1995,
p. 426; Todd et al. 2004, pp. 193-194).
However, given the remote locations of emperor penguin colonies and
the difficulties of accessing them, the number of colonies may vary
from the 45 reported. At the time of the 1990's compilation of emperor
penguin numbers and colony locations cited above, Woehler (1993, p. 5)
stated that many colonies had not been observed or counted for many
years, with in some cases, the most recent data dating to the 1950s and
1960s. On the other hand, in describing a new colony along the coast of
Wilkes Land near a research base that had already been utilized for 35
years, Melick and Bremmers (1995, p. 427) cited a very strong
likelihood that more emperor penguin colonies were waiting to be
discovered in this area and that such discoveries could significantly
raise the present estimates of emperor penguin numbers.
Breeding Areas
Emperor penguin breeding colonies are variable in size. In 1993,
Woehler (1993, pp. 2-9) provided size estimates for 36 of the 42
colonies. Adding the 3 newly discovered colonies cited above, colony
size for 39 colonies ranged from under 100 breeding pairs to 22,354
breeding pairs (with 2 colonies above 20,000 breeding pairs, 6 colonies
between 10,000 and 20,000 pairs, 21 colonies between 1,000 and 10,000
pairs, and 10 colonies below 1,000 pairs). The largest colonies at Cape
Washington and Coulman Island had 19,364 and 22,137 downy chicks (and
accordingly the same number of breeding pairs), respectively, in 1990
(Kooyman 1993, p. 145), and 23,021 and 24,207 chicks, respectively, in
2005 (Barber-Meyer et al. 2007b, p. 7).
Emperor penguin breeding colonies are also variable in physical
location. Scientists have attempted to describe the most important
physical characteristics of colony locations and how they influence
colony size. For six western Ross Sea colonies, Kooyman (1993, pp. 143-
148) identified stable land-fast ice, nearby open water, access to
fresh snow (for drinking water and thermal protection), and shelter
from the wind as physical characteristics. At Beaufort Island, Cape
Crozier, and Franklin Island, limited land-fast ice areas seem to
dictate colony size (179, 477, and 4,989 fledgling chicks,
respectively) because the birds were unable to move away from snow and
ice that had been contaminated by guano over the course of the breeding
season, and they had limited options to shelter from winds. At Coulman
Island and Cape Washington, the largest known emperor penguin colonies
(22,137 and 19,364 fledgling chicks, respectively), suitable land-fast
ice areas were unlimited with a good base of snow. Access to open water
in the winter is another major characteristic. Known locations of
emperor penguin colonies have been found to be associated with known
coastal polynyas-areas of winter open water in East Antarctica (Massom
et al. 1998, p. 420).
Localized changes in colony size and breeding success have been
recorded at specific colonies and attributed to local-or regional-scale
factors. Changes in the physical environment can have an impact on
individual colonies, especially smaller ones, which show higher year-
to-year variation in live chick counts than larger colonies (Barber-
Meyer et al. 2007b, p. 4).
Feeding Areas
The primary foods of emperor penguins are krill (Euphausia
superba), Antarctic silverfish (Pleurogramma antarcticum), and some
types of lanternfish and squid (Kirkwood and Robertson 1997, p. 165;
Kooyman 2002, p. 491). The proportion of each of these in the diet is
variable according to colony location and season, with fish comprising
20 to 90 percent, krill 0.5 to 68 percent, and squid 3 to 65 percent by
weight in the diet (Kooyman 2002, pp. 488, 491).
During their winter feeding trips, female emperor penguins travel
over ice to reach areas of open water or polynyas, which are generally
accessible from emperor penguin colonies (Massom et al. 1998, p. 420).
Penguins from the Auster and Taylor colonies on the Mawson coast of
Antarctica, carrying time-depth recorders, took about 8 days to reach
the ice edge and spent 50-60 days at sea foraging. They foraged about
62 mi (100 km) northeast of the colony in water over the outer
[[Page 77294]]
continental shelf and shelf slope. As penguins are visual foragers,
foraging was limited to daylight, with penguins entering the water just
after dawn and emerging at dusk after spending on average 4.71 hours in
the water (Kirkwood and Robertson 1997, pp. 155, 168). Both on the
journey north and between foraging days at sea, females occasionally
huddled together in groups on the ice to minimize heat loss (Kirkwood
and Robertson 1997, p. 161).
As mentioned above, juvenile penguins leaving their natal colonies
upon fledging have been radio-tracked to 56.9[deg] S latitude, the area
of the Antarctic Convergence where they presumably feed (Kooyman et al.
1996, p. 397).
Molting Areas
The summer molt is a critical stage in the life history of the
emperor penguin. The birds must find stable land-fast ice or pack ice
to allow them to stay ashore for the 1-month molt (Kooyman et al. 2004,
pp. 281-290; Wienecke et al. 2004, pp. 83-91). In the western Ross Sea,
penguins departing their breeding grounds in December generally
traveled an average straight-line distance of 745 mi (1,200 km) from
their colonies to molt in the large consolidated pack-ice area in the
eastern Ross Sea (Kooyman et al. 2000, p. 272). In 1998, molting birds
were sighted on the southern edge of the summer pack ice in the western
Weddell Sea (Kooyman et al. 2000, p. 275), and birds sighted were
assumed to be from colonies in the eastern Weddell Sea up to 869 mi
(1,400 km) to the east, although some may have come from the Snow Hill
Colony recently discovered to the north of this area (Kooyman et al.
2000, pp. 275-276). Along the Mawson Coast, penguins departing colonies
prior to molt traveled for 22-38 days and reached molting locations up
to 384 mi (618 km) from the colony. Unlike Ross Sea penguins, they did
not travel directly to consolidated pack-ice locations, but first moved
north, apparently to feed, and then returned to molt in nearshore areas
where land-fast ice persisted throughout the summer (Wienecke et al.
2004, p. 90).
Abundance and Trends
There are estimated to be 195,000 emperor penguin pairs breeding in
approximately 45 colonies around the perimeter of the Antarctic
continent. The population is believed to be stable rangewide (Woehler
1993, pp. 2-7; Ellis et al. 2007, p. 5) and in the Ross Sea (Barber-
Meyer et al. 2007b, p. 3). As cited above, even as overall numbers
remain stable, fluctuations in individual colony size have been
reported for a number of colonies (Kato et al. 2004, p. 120; Kooyman et
al. 2007, p. 37; Barber-Meyer et al. 2007b, p. 7; Barbraud and
Weimerskirch 2001, pp. 183-186) and seem to reflect the impacts of
local and regional physical and climatic variation in the harsh
Antarctic environment, as well as the resilience of this species in
responding to this variation.
Other Status Classifications
The emperor penguin is listed in the category of `Least Concern' on
the 2007 IUCN Red List on the basis of its large range and stable
global population (BirdLife International 2007, p. 1). A species is
considered of least concern when it has been evaluated against the IUCN
criteria and does not qualify for `Critically Endangered,'
`Endangered,' `Vulnerable,' or `Near Threatened.' Widespread and
abundant species are included in this category (BirdLife International
2007, p. 1).
Summary of Factors Affecting the Species
Factor A: The Present or Threatened Destruction, Modification, or
Curtailment of Its Habitat or Range
The breeding range of the emperor penguin consists of land-fast ice
along the continental margins of Antarctica. The emperor penguin is an
ice-dependent species. Therefore, emperor penguins are vulnerable to
changes in the winter land-fast ice and polynya system (Ainley 2005, p.
178; Croxall 2004, p. 90), which comprises their breeding habitat, and
to changes in the pack ice or residual land-fast ice, which they use
for summer molt haul-out areas (Barber-Meyer et al. 2007b, p. 11;
Kooyman et al. 2004, p. 289).
Studies reviewed below indicate that the emperor penguin lives in a
harsh and highly changeable environment. Changes and perturbations that
affect emperor penguins occur on daily, seasonal, annual, decadal, and
historical timeframes. Localized changes in colony size and breeding
success have been recorded at specific colonies and attributed to
local- or regional-scale factors.
Changes in the physical environment can have an impact on
individual colonies, especially smaller marginal ones that show higher
year-to-year variation in live chick counts than larger colonies
(Barber-Meyer et al. 2007b, pp. 7, 10). A dramatic example of physical
changes to the breeding and foraging environment comes from the
periodic calving of giant icebergs from the Ross Ice Shelf, expected
every 3-4 decades on average (Arrigo et al. 2002, p. 4).
For example, the calving in 2000 and subsequent grounding of two
giant icebergs in the Ross Sea severely affected the Cape Crozier and
Beaufort Island emperor penguin colonies. In 2001, nesting habitat was
destroyed at Cape Crozier by the collision of iceberg B15A with the
northwest tongue of the Ross Ice Shelf, dislodging the ice shelf and
creating a huge collection of iceberg rubble. Adult mortality was high,
either due to trauma from shifting and heaving sea ice or subsequent
starvation of penguins trapped in ravines. The colony produced no
chicks in 2001. The high mortality of adults (Kooyman et al. 2007, p.
37) and continued instability and unsuitability of the area of this
traditional colony contributed to a reduction in chick production that
ranged from 0 to 40 percent of the high count of 1,201 chicks produced
in 2000 (Kooyman et al. 2007, pp. 31, 34-35). Chick counts fluctuated
from 0 in the iceberg year of 2001, to 247 in 2002, to 333 in 2003, to
475 in 2004, to 0 in 2005, to 340 chicks in 2006. The situation in 2005
was highly unusual because the 437 adults in the colony in mid-October
showed no signs of breeding (i.e., no eggs and no chicks). The reason
for breeding failure was not apparent (Barber-Meyer et al. 2007b, pp.
7, 9). However, preliminary reports from 2006 indicated that breeding
success at Cape Crozier was again improved with about 340 live chicks
(Barber-Meyer et al. 2007b, p. 9). Recovery may have been slowed as a
consequence of the high adult mortality in 2001. While breeding birds
have persistently returned to the colony after the iceberg departed in
2003, they may be waiting for conditions at the colony to improve
before breeding there again (Kooyman et al. 2007, p. 37).
At the Beaufort Island colony, the arrival of iceberg B15A, along
with iceberg C16 in 2001, did not physically affect the colony
substrate itself, but separated the breeding birds in the colony from
their feeding area in the Ross Sea polynya with a 93-mi (150-km) long
barrier. In the 2001-2004 breeding seasons, adult birds were forced to
walk up to 56 mi (90 km) before being able to enter the water. Chick
counts in 2004, the worst year of this period, dropped to 131 (6
percent of the high count of 2,038 in 2000). Unlike at Cape Crozier,
once the icebergs finally left the area by 2005, the surface conditions
of the colony were restored to pre-iceberg condition and, with
accessibility to the Ross Sea polynya restored, the first post-iceberg
breeding season saw recovery in chick production to 446 chicks (Kooyman
et al. 2007, p. 36) to 628
[[Page 77295]]
chicks (Barber-Meyer et al. 2007b, p. 7), a little under one-third of
2000 levels.
Changes in the physical environment have also been shown to affect
the food sources of emperor penguins in the Ross Sea (Arrigo et al.
2002, pp. 1-4). The presence of the B15A iceberg in the Ross Sea
blocked the normal drift of pack ice and resulted in heavier spring and
summer pack ice in the region in 2000-01. This resulted in a delay in
the initiation of the annual phytoplankton bloom in some areas and
failure to bloom in others, with a reduction in primary productivity in
the Ross Sea region by 40 percent. While emperor penguin diets were not
reported, Adelie penguin diets shifted to a krill species normally
associated with extensive sea-ice cover during the first year of this
grounding event (Arrigo et al. 2002, p. 3). The very large emperor
penguin colony at Cape Washington, about 124 mi (200 km) away,
experienced reduced chick abundance in the period when B15A was in the
area; the iceberg's presence may have modified breeding behavior and
chick nurturing in some way. Chick numbers rebounded in 2004 and 2005
(Barber-Meyer et al. 2007b, p. 10).
Future iceberg calving events are likely to affect emperor penguin
colonies in the Ross Sea. Calving of the Ross Ice Shelf, which led to
the formation of icebergs B15A and C16, is described as a cyclical
phenomenon expected every 3-4 decades on average from the northeast
corner of the ice shelf. While the Ross Ice Shelf front has been
relatively stable over the last century, such events are a consequence
of the longer-term behavior of the West Antarctic Ice Sheet in the Ross
sector. Current retreat of the Western Antarctic Ice Shelf has been
underway for the past 20,000 years since the last glacial maximum, and
retreat is expected to continue, with or without global climate warming
or sea-level rise (Conway et al. 1999, pp. 280-283). Efforts are
underway to understand and predict the overall behavior of the West
Antarctic Ice Sheet (Bentley 1997, pp. 1,077-1,078; Bindschalder 1998,
pp. 428-429; Bindschalder et al. 2003, pp. 1,087-1,989), but we are not
aware of any current predictions of local-scale changes in calving
rates in the Ross Sea in the near future.
A number of studies have attempted to relate population changes at
individual emperor penguin colonies to the effects of regional and
global oceanographic and climatic processes affecting sea surface
temperatures and sea-ice extent. In the Ross Sea, which contains the
highest densities of emperor penguins in Antarctica and the largest and
smallest and most southerly of all penguin colonies, Barber-Meyer et
al. (2007b, pp. 3-11) examined large-scale and local-scale climatic
factors against trends in chick abundance in six colonies in the
western Ross Sea from 1979-2005. They found that overall emperor
penguin numbers in the Ross Sea were stable during this period. They
were unable to find any consistent correlation between trends in chick
abundance and any of the climate variables of sea-ice extent--sea
surface temperature, annual Southern Oscillation Index, and Southern
Hemisphere Annular Mode. They determined that chick abundance in
smaller colonies was more highly variable than in large colonies,
suggesting that small colonies occupy marginal habitat and are more
susceptible to environmental change. While they concede that
significant local events such as the grounding of iceberg B15A may have
masked subtle relationships with local sea-ice extent and large-scale
climate variable, their analysis indicated that the environmental
change most affecting chick abundance is fine-scale sea-ice extent and
local weather events (Barber-Meyer et al. 2007b, pp. 3-11).
Similar analyses have been conducted for a single, small emperor
penguin colony located near the D'Urmont D'Urville Station in the Point
Geologie archipelago in Adelie Land in a study that has been widely
cited as demonstrating the impacts of climate change on this species
(Barbraud and Weimerskirch 2001, pp. 183-186). In the late 1970s, a 50-
percent decline in the number of breeding pairs at this small colony
(from 5,000-6,000 pairs to 2,500-3,000 pairs) occurred at the time of
an extended period of warmed winter temperatures at the colony and
reduced sea-ice extent in the vicinity. After the period of decline,
numbers stabilized at half the pre-1970 levels for the next 17 years.
Meteorological data collected at the station were used as a proxy for
sea surface temperatures. The authors found that overall breeding
success was not related to sea surface temperatures or sea-ice extent.
Instead, the decrease was attributed to increased adult mortality.
Emperor penguin survival apparently was reduced when temperatures were
higher and penguins survived better when sea-ice extent was greater.
The authors hypothesized that with decreased sea-ice extent during the
warmer period in the late 1970s, krill recruitment may have been
reduced, making it more difficult for adults to find food. The authors
attributed an increased variability in breeding success during the 17
years of population stability after this period to a combination of
local- and annual-scale physical factors, such as blizzards and early
break out of the ice supporting the colony (Barbraud and Weimerskirch
2001, pp. 183-186). This increased variability over the last 17 years
is consistent with the observations for the Ross Sea (Barber-Meyer et
al. 2007b, p. 7), where annual variability in breeding success is
larger for smaller colonies.
The conclusions of the Barbraud and Weimerskirch study and the
ability to generalize based on its results have been questioned by
several authors. As noted above, the results and conclusions are not
supported by a larger-scale study of six large and small penguin
colonies in the Ross Sea, which represent 25 percent of the world's
population (Barber-Meyer et al. 2007b, pp. 10-11). In discussing this
study, Ainley et al. (2005, pp. 177-180) concluded that the confounding
factors of severe blizzards and increases in early departure of the
land-fast ice nesting substrate suggest that the continued low
population numbers at Point Geologie have not been fully explained, and
they questioned the conclusion that higher mortality of adult emperor
penguins during 1976-1980 was caused by increased sea surface
temperatures. Croxall et al. (2002, p. 1,513) stated ``that current
data on environment-prey-population interactions are insufficient for
deriving a single coherent model that explains these observations.''
Further work at this same Antarctic location, building from local
observations of seabird dynamics and measurements of regional sea-ice
extent and the Southern Oscillation Index, led Jenouvrier et al. (2005,
p. 894) to suggest that in the late 1970s there may have been a regime
shift in cyclical Antarctic environmental factors such as sea-ice
extent and the Southern Oscillation Index, which may have affected the
dynamics of the Southern Ocean. In another paper, Weimerskirch et al.
(2003, p. 254) suggested that the decrease in sea-ice extent in the
late 1970s in the Adelie Land area could be related to a regional
increase in temperatures in the Indian Ocean during that period.
In related work, Ainley et al. (2005, pp. 171-182) further
described decadal-scale changes in the western Pacific and Ross Sea
sectors of the Southern Ocean during the early to mid-1970s and again
during 1988-1989. These large-scale periods of warming and cooling and
corresponding changes in weather and sea-ice patterns were linked to
decadal shifts in two atmospheric pressure-related systems in the
region. The first
[[Page 77296]]
is the semi-annual oscillation (the strengthening and weakening of the
circumpolar trough of low pressure that encircles Antarctica), and the
second is the Antarctic oscillation (now referred to as the Southern
Annual Mode), the pressure gradient between mid latitudes and high
latitudes (Ainley et al. 2005, p. 172). The study showed that
environmental changes in a number of sea-ice variables during these
cyclical periods, including polynya size, led to corresponding
reductions and increases in a number of Adelie penguin colonies in the
Ross Sea and changes in the number of adults breeding and the
reproductive output at a number of individual Adelie penguin colonies
in the Ross Sea. The authors attempted to compare Ross Sea data for
Adelie penguins with the observations at Pointe Geologie for emperor
penguins, but data from the much more detailed subsequent studies of
Barber-Meyer et al. (2007b, pp. 3-11) leave the reader with only the
general conclusion that the two species respond differently to these
cyclical environmental changes (Ainley et al. 2005, p. 171).
The primary breeding and winter foraging habitat of the emperor
penguin is land-fast ice along the margins of the Antarctic continent.
While overall populations are stable, local- or regional-scale
variations in physical, oceanographic, and climatological processes, as
described above, lead to year-to-year variations in chick production or
colony breeding success in colonies scattered widely along the coast of
Antarctica. Field observations show that emperor penguins respond to
such factors, when they occur, but given the stability of penguin
numbers around Antarctica, we have found no consistent trends with
respect to the destruction, modification, or curtailment of their
habitat or range.
With respect to larger-scale observations of the climate of
Antarctica and the extent of the sea ice that makes up the primary
habitat of the emperor penguin, the Working Group I report to the
Fourth Assessment Report of the Intergovernmental Panel on Climate
Change (IPCC), which reviewed the observations on the physical science
basis for climate change, found that ``Antarctica sea ice extent
continues to show interannual variability and localized changes, but no
statistically significant overall trends, consistent with lack of
warming reflected in atmospheric temperatures averaged across the
region'' (IPCC 2007, p. 9).
Observations of climate and ice conditions are not uniform
throughout Antarctica in any particular season or year. Attempts to
describe and understand long-term observed conditions and to predict
future conditions either on the basis of the demographic behavior of
individual penguin colonies or on the basis of global-scale climate
observations are difficult and incomplete. At a continent-wide scale,
observational studies show sea-ice cover decreased significantly in the
1970s, but has increased overall since the late 1970s (Parkinson 2002,
p. 439; Parkinson 2004, p. 387; Yuan and Martinson 2000, p. 1,712).
More recently, the IPCC reported that Antarctic results show a small,
positive trend in sea-ice extent that is not statistically significant
(Lemke 2007, p. 351).
With respect to regional trends along the continent, satellite
observational studies have shown, for Southern Ocean regions adjoining
the South Atlantic, South Indian, and southwest Pacific Oceans,
increasing trends in sea-ice cover, particularly during non-winter
months. Regions adjoining the southeast Pacific Ocean, however, have
shown decreasing trends in sea-ice coverage, particularly during the
summer months (Stammerjohn and Smith 1997, p. 617; Kwok and Comiso
2002, p. 501; Yuan and Martinson 2000, p. 1,712). The distribution of
sea-ice-extent anomalies (areas of more- or less-than-average sea ice)
observed around the continent is bimodal with increased ice cover in
the Indian Ocean sector, a slight decrease between the eastern Indian
Ocean and Western Pacific, large increases in the western Pacific Ocean
and Ross Sea sector, a large decrease in the Bellinghausen and Amundsen
Seas of the eastern Pacific sector, and a large increase in the Weddell
Sea (Curran et al. 2003, p. 1,205; Yuan and Martinson 2000, p. 1,712).
Attempts to link south polar sea-ice trends to climate outside this
polar region are extremely complex. In statistical and observational
studies of Antarctic sea-ice extent and its global variability, sea-ice
anomalies in the Amundsen Sea, Bellinghausen Sea, and Weddell Gyre,
corresponding to the Western Antarctic Peninsula region, showed the
strongest links to extrapolar climate (Yuan and Martinson 2000, p.
1,697) and to variations in the Southern Oscillation Index (Kwok and
Comiso 2000, p. 500); however, these factors did not explain the trends
of stable or increasing sea-ice extent for the majority of the
continental coast of Antarctica, which encompasses the range of the
emperor penguin.
Future Projections
With respect to the future of Antarctica, the IPCC reported, ``in
20th and 21st century simulations, Antarctic sea ice cover is projected
to decrease more slowly than in the Arctic, particularly in the
vicinity of the Ross Sea where most models predict a minimum in surface
warming. This is commensurate with the region with the greatest
reduction in ocean heat loss, which results from reduced mixing of the
ocean'' (Meehl et al. 2007, p. 770).
Simulation models, comparing 1980-2000 observed winter and summer
mean sea-ice concentrations around Antarctica with modeled 2080-2100
sea-ice concentrations, predicted declines in sea-ice concentrations in
this timeframe (Bracegirdle et al. 2008, p. 8; Meehl et al. 2007, p.
771). While these models showed extensive deviation around mean
predictions, they provided a general predictive picture of future
Antarctic sea-ice conditions in the range of the emperor penguin. They
showed winter sea-ice reductions by 2080-2100, with ice concentrations
remaining high around the bulk of the continent and highest in the
Ross, Amundsen, and Weddell Seas, and around the Mawson Coast in the
Indian Ocean sector. Summer sea-ice concentrations also retreat, with
sea ice persisting in the Ross and Weddell Seas and apparently greatly
reduced or not persisting in the Indian Ocean sector. These large-scale
model predictions seem to indicate that emperor penguins, especially in
the Ross and Weddell Seas, are likely to continue to encounter suitable
sea-ice habitat for breeding in the winter and molting in the summer in
the 100-year timeframe. The IPCC is very clear on the limitations of
these models--the report contains a section discussing the limitations
and biases of sea-ice models and finding that even in the best cases,
which involve Northern Hemisphere winter sea-ice extent, ``the range of
simulated sea ice extent exceeds 50% of the mean and ice thickness also
varies considerably, suggesting that projected decreases in sea ice
remain rather uncertain'' (Randall et al. 2007, p. 616). It is
difficult and premature, given the large geographic scale of these
models, their extensive deviations around mean predictions, and their
100-year timeframe, to make specific predictions about the sea-ice
conditions in any particular region of emperor penguin habitat around
Antarctica. This is particularly difficult when empirical evidence to
date suggests that such continent-wide sea-ice declines have not yet
begun.
With respect to atmospheric temperatures, increases in the Southern
Annular Mode (SAM) index (a monthly measure of differences in sea-level
atmospheric pressure between the mid
[[Page 77297]]
latitudes and high latitudes of the Southern Hemisphere) (Trenberth et
al. 2007, p. 287) from the 1960s to the present are associated with a
strong warming over the Antarctic Peninsula and, to a lesser extent,
with cooling over parts of continental Antarctica, the area of the
range of the emperor penguin (Trenberth et al. 2007, p. 339). There is
continued debate as to whether these trends in the SAM are related to
stratospheric ozone depletion and to greenhouse gas increases
(Trenberth et al. 2007, p. 292) or to decadal variation in
teleconnections or large-scale patterns of pressure and circulation
anomalies that span vast geographical areas and ``modulate the location
and strength of storm tracks and poleward fluxes of heat, moisture and
momentum'' (Trenberth et al. 2007, pp. 286-287). Reconstructions of
century-scale records based on proxies of the SAM found that the
magnitude of the current trend may not be unprecedented even in the
20th century (Trenberth et al. 2007, pp. 292-293). The response of the
SAM to the ozone hole in the late 20th century, which has also had a
warming affect on temperature, confounds simple extrapolation into the
future (Christensen et al. 2007, p. 907).
At the regional scale, the IPCC reported that very little effort
has been spent to model the future climate of Antarctica (Christenson
2007, p. 908). Annual warming over the Antarctic continent is predicted
to be ``moderate but significant'' (2.5-9 [deg]F (1.4-5 [deg]C), with a
median of 4.7 [deg]F (2.6 [deg]C)) at the end of the 21st century
(Christenson 2007, p. 908). Models tend to show that the current
pattern, which involves warming over the western Antarctic Peninsula
and little change over the rest of the continent, is not projected to
continue through the 21st century (Christenson 2007, p. 908). Ainley et
al. (unpublished ms, n.d., pp. 1, 26-29), using a composite of selected
climate models for 2025-2070, projected that an increase in earth's
tropospheric temperature by 3.6 [deg]F (2 [deg]C) would result in a
marked decline or disappearance of 50 percent of emperor colonies (40
percent of the population) at latitudes north of 70[deg] S latitude
because of severe decreases in pack-ice coverage and ice thickness,
especially in the eastern Ross and Weddell Seas. Without further review
and testing of this model, it would be premature to use this model's
results to make specific predictions about the sea-ice conditions in
the emperor penguin habitat around Antarctica.
We have examined current conditions and predictions for changes in
sea ice and temperatures around Antarctica for the coming 100 years,
which remain very general. We have paid particular attention to sea ice
because it is the dominant habitat feature of the emperor penguin's
life cycle. To date, evidence does not support the conclusion that
directional changes in temperature or sea-ice extent are already
occurring in the habitat of the emperor penguin. We do not discount the
strong likelihood that predicted sea-ice changes will eventually reduce
the habitat of emperor penguins. However, on the basis of: (1) Current
observed conditions; (2) the stability of emperor penguin colonies
throughout their range; (3) the likelihood in the 100-year timeframe
that emperor penguin habitat requirements will continue to be met in
current core areas of their range; and (4) the uncertainty of current
large-scale predictive models and the absence of fine-scale climate
models predicting conditions for the range of the emperor penguin, we
conclude that there is not sufficient evidence to find that climate-
change effects to the habitat of the emperor penguin will threaten the
emperor penguin within the foreseeable future.
On the basis of this information, we conclude that the present or
threatened destruction, modification, or curtailment of the emperor
penguin's habitat or range is not a threat to the species in any
portion of its range now or in the foreseeable future.
Factor B: Overutilization for Commercial, Recreational, Scientific, or
Educational Purposes
The ecotourism industry in Antarctica has been growing, with an
increase from 6,750 tourists during the 1992-93 summer season to a
projected 35,000 tourists in 2007-08 (Austen 2007, p. 1). A few emperor
penguin colonies have become the focus of increased, but limited,
tourism activities in Antarctica. In particular, the newly discovered
Snow Hill colony near the Antarctic Peninsula, which numbers about
4,000 pairs (Todd et al. 2004, pp. 193-194), is accessible to ice-
breaking vessels coming to the Antarctic Peninsula from the southern
ports of South America. The International Association of Antarctica
Tourism Operators (IAATO 2007b, p. 1) reported that 909 visitors landed
to visit the Snow Hill Colony in the 2006-07 summer season. These
visitors all came off one vessel, the icebreaker Kapitan Khlebnikov. In
November 2006, Burger and Gochfeld (2007, pp. 1,303-1,313) reported
that there was one visit in 2004, no tour visits in 2005, and at least
three visits in 2006. These authors concluded it was unlikely tourists
would visit early in the season when chicks are most vulnerable.
Burger and Gochfeld (2007, pp. 1,303-1,313) examined whether the
presence of tourists had an impact on the movement of emperor penguins
between the colony and the sea. They found that penguins noticing the
presence of people paused more often and for longer in their movements
than those passing at a greater distance. The authors provided
recommendations for tourist behavior to mitigate the effects of tourist
presence on traveling penguins.
For the remainder of continental Antarctica tourists, visits and
landings are extremely limited. For example, in 2006-07, 263 people are
recorded as landing from one ship, again the icebreaker Kapitan
Khlebnikov, at Cape Washington in the Ross Sea, the site of one of the
largest emperor penguin colonies. Only 13 sites off the Antarctic
Peninsula are recorded as receiving tourists (IAATO 2007c, p. 1).
The Antarctic Treaty sets out requirements for tourism operators
and tourists entering the Antarctic Treaty region. Tourism operators
are required to operate under the Antarctic Treaty's Guidance for those
Organising and Conducting Tourism and Non-governmental Activities in
the Antarctic: Recommendation XVIII-1, adopted at the Antarctic Treaty
Meeting, Kyoto, 1994. This detailed guidance sets out requirements for:
(1) Advance planning and advanced notification, as well as post-visit
reporting of any proposed activities in the region, (2) preparation and
compliance with contingency-response plans, including for waste
management and marine pollution, and (3) awareness of and proper
permitting related to Specially Protected Areas, Sites of Special
Scientific Interest, and Historic Sites and Monuments (International
Association of Antarctica Tour Operators (IAATO 2007a, p. 1). The
Antarctic Treaty Guidance for Visitors to the Antarctic: Recommendation
XVIII-1, adopted at the Antarctic Treaty Meeting, Kyoto, 1994 is
intended to ensure that all visitors to the Antarctic are aware of and
comply with the treaty and its Protocol for Environmental Protection.
This focuses in particular on the prohibition on taking or harmful
interference with Antarctic wildlife, including care not to affect them
in ways that cause them to alter their behavior, and on preventing the
introduction of nonnative plants or animals into the Antarctic
(Antarctic Treaty Secretariat 2007, pp. 1-5). Scientific research is
also strictly regulated under the Antarctic Treaty.
[[Page 77298]]
On the basis that tourist activities reach very few penguin
colonies, the number of tourists are limited, and their behavior is
well regulated by the Antarctic Treaty, we find that tourism is not a
threat to the emperor penguin in any portion of its range now or in the
foreseeable future.
In addition, we are unaware of any overutilization for other
commercial, recreational, scientific, or educational purposes that is a
threat to the emperor penguin in any portion of its range now or in the
foreseeable future.
Factor C: Disease or Predation
Antarctic species, such as the emperor penguin, are potentially
susceptible to the introduction of avian diseases from outside the
region (Jones and Shellam 1999, p. 182). Gardner et al. (1997, p. 245)
found antibodies of an avian pathogen, Infectious Bursal Disease Virus
(IBDV), in 65.4 percent of 52 emperor penguin chicks sampled at the
Auster colony on the Mawson Coast in 1995, although no evidence of
clinical disease was present. This pathogen of domestic chickens may
have been introduced by humans into this area. The authors suggested
that careless or inappropriate disposal of poultry products, allowing
access by scavenging birds or inadvertent tracking by humans, was a
potent source for spread of this environmental contaminant. The authors
concluded that the potential for tourists or expeditions to be vectors
of disease may pose a significant threat to Antarctic avifauna.
Although disease may be a stressor to penguins, the Antarctic Treaty
Parties have subsequently addressed concerns over the introduction of
disease and invasive species in protocols to the treaty and guidelines
arising out of them. These are discussed below under Factor D.
We are unaware of any information relative to detrimental predation
impacts on the emperor penguin, either from native or nonnative
species.
In conclusion, we find that neither disease nor predation is a
threat to the species in any portion of its range now or in the
foreseeable future.
Factor D: The Inadequacy of Existing Regulatory Mechanisms
The Antarctic Treaty, which entered into force in 1961, applies to
the area south of 60 [deg]S latitude including all ice shelves
(Antarctic Treaty area). The primary purpose of the treaty, which has
28 full members or Parties, is to ensure ``in the interests of all
mankind that Antarctica shall continue forever to be used exclusively
for peaceful purposes and shall not become the scene of international
discord'' (Jatko and Penhale 1999, p. 8). Measures for the Conservation
of Antarctic Fauna and Flora arising out of language in Article IX of
the treaty concerning ``preservation and conservation of living
resources in Antarctica'' were adopted in 1964. They were incorporated
into the Protocol on Environmental Protection to the Antarctic Treaty,
which was ratified in 1991 and entered into force in January 1998. In
the protocol, the Parties to the Antarctic Treaty committed themselves
to the comprehensive protection of Antarctica's environment and
dependent and associated ecosystems, and they designated Antarctic as a
reserve devoted to peace and science (Jatko and Penhale 1999, p. 9).
Five annexes to the protocol address specific areas of environmental
protection, including environmental impact assessment, conservation of
Antarctic fauna and flora, waste disposal and waste management,
prevention of marine pollution, and the designation and management of
protected areas. Annex II of the Protocol includes prohibitions on
killing, capturing, handling, or disturbing animals or harmfully
interfering with their habitat, as well as tight restrictions on the
introduction of nonnative species; Annex III provides a comprehensive
system of requirements for management of wastes generated in
Antarctica, including elimination of landfills; and Annex IV addresses
requirements to prevent marine pollution from ships operating in the
Antarctic Treaty area (Jatko and Penhale 1999, pp. 9-10). As noted
above, guidelines for activities in Antarctica directly address these
prohibitions on the introduction of nonnative species as well as
disposal of garbage (IAATO 2007a, pp.1-4). The Scientific Committee on
Antarctic Research, originally established by the International Council
of Scientific Unions, provides scientific advice to the Treaty Parties
(Jatko and Penhale 1999, p. 8).
Because the Antarctic Treaty does not affect the rights of any
State under international law with respect to the high seas, a series
of separate conventions have been negotiated and ratified with respect
to the exercise of rights in the seas around Antarctica. In particular,
CCAMLR addresses the conservation of marine resources. Article II
``defines the objective of this Convention as the conservation of
Antarctic marine living resources and states that conservation includes
rational use of harvesting'' (Jatko and Penhale 1999, p. 11). CCAMLR
operates on three principles: (1) Prevention of population decrease
below that which ensures stable recruitment of harvested species; (2)
maintenance of the ecological relationships among harvested, dependent,
and related species; and (3) prevention of changes or minimization of
risks of ecosystem changes. CCAMLR has been active in assessing the
status of krill and species dependent upon krill, such as birds and
mammals; regulating the harvest of Patagonian tooth fish (Dissostichus
spp.); and ecosystem monitoring with the goal of detecting changes in
critical components of ecosystems.
We find, on the basis of the protection and management of Antarctic
ecosystems under the Antarctic Treaty and CCAMLR, that the inadequacy
of regulatory mechanisms is not a threat to the emperor penguin in any
portion of its range now or in the foreseeable future.
Factor E: Other Natural or Manmade Factors Affecting the Continued
Existence of the Species
Fishery Interactions
We have found no evidence of fishing impacts on emperor penguins in
the foraging range of adults along the continental margins. Kooyman et
al. (1996, p. 397) found that juveniles range north into waters where
commercial fishing may occur and noted the importance of determining
the dispersal patterns of the young to ensure adequate protection.
Kooyman (2002, p. 492) also noted that the Antarctic Treaty and CCAMLR
extend only to the 60th parallel in this region of Antarctica. However,
we are unaware of any reports of fisheries interactions with emperor
penguin juveniles and have no reason to believe that this potential
stressor will occur at a level to impact this species in the future.
Oil Pollution
Annex IV of the Protocol on Environmental Protection to the
Antarctic Treaty sets out requirements to prevent pollution from ships
operating in the Antarctic Treaty area (Jatko and Penhale 1999, p. 10).
The November 2007 sinking of the cruise ship MV Explorer near the
Antarctic Peninsula illustrates the possibility of oil spills and other
ship-based pollution from increased vessel traffic in Antarctic waters.
The MV Explorer, which held about 48,000 gallons (181,680 liters) of
marine diesel fuel when it sank (Austen 2007, p. 1), did not sink near
emperor penguin colonies, but it did sink in the vicinity of colonies
of other penguin species. As noted in the discussion of Factor B above,
emperor penguin
[[Page 77299]]
colonies are not a significant destination of the increasing tourist
activity in Antarctica. The wide dispersal of emperor penguin colonies
around Antarctica mitigates the concern that a single vessel accident
could affect the population of emperor penguins, as does the fact that
emperor penguin activity at rookeries may be reduced at the time of
year when vessel traffic becomes significant. Vessel operations in the
vicinity of emperor penguin colonies, near summer molting areas or
elsewhere in their foraging range, remain a source of concern. Although
we consider this a potential stressor to the emperor penguin, we have
no reason to believe oil pollution will occur at a level to impact this
species in the future.
Therefore, we find that fishery interactions and oil pollution are
not threats to the emperor penguin in any portion of its range now or
in the foreseeable future.
Foreseeable Future
A general discussion of threatened species and foreseeable future
can be found above in the southern rockhopper penguin Foreseeable
Future section.
In considering the foreseeable future as it relates to the status
of the emperor penguin, we analyzed the stressors acting on this
species. We reviewed the historical data to identify any relevant
existing trends that might allow for reliable prediction of the future
(in the form of extrapolating the trends). We also considered whether
we could reliably predict any future events (not yet acting on the
species and, therefore, not yet manifested in a trend) that might
affect the status of the species.
As discussed above in the five-factor analysis, we were unable to
identify any significant trends with respect to the stressors we
identified for this species: (1) Physical changes in the sea-ice and
marine habitat; (2) potential introduction of avian diseases from
outside the region; (3) potential fishery interactions with juveniles
that range north into waters where commercial fishing may occur; and
(4) possible oil pollution in the vicinity of summer molting areas or
in the penguin's foraging range. There is no evidence that any of the
stressors are growing in magnitude. Thus, the foreseeable future
includes consideration of the ongoing effect of current stressors at
comparable levels.
There remains the question of whether we can reliably predict
future events (as opposed to ongoing trends) that will likely cause the
species to become endangered. As we discuss in the finding below, we
can reliably predict that physical changes in the sea-ice and marine
habitats will continue to have an impact on individual colonies,
especially smaller marginal colonies, but we have no reason to believe
the physical changes will have population level impacts. Thus, the
foreseeable future includes the consideration of the effects of such
changes on the viability of the emperor penguin.
Emperor Penguin Finding
We have carefully assessed the best available scientific and
commercial information regarding the past, present, and potential
future threats faced by the emperor penguin above. To determine whether
the stressors identified above individually or collectively rise to the
level of a threat such that the emperor penguin is in danger of
extinction throughout its range or likely to become so within the
foreseeable future, we considered whether the stressors were causing a
long-term, population decline or were likely to do so in the future.
As discussed above, the overall emperor penguin population is
estimated at 195,000 breeding pairs in approximately 45 colonies
distributed around the perimeter of the Antarctic continent. We
consider the population to be currently stable, and we are not aware of
significant historical or current declines. Observed fluctuations in
numbers at specific colonies, particularly smaller ones, are ongoing
and have been attributed to physical events in the harsh Antarctic
environment and seasonal, annual, and longer cyclical climatic or
meteorological events. While observations of emperor penguin colonies
are by nature constrained by the logistics of reaching remote sites,
and many colonies are rarely visited or poorly described (Barber-Meyer
et al. 2007a, p. 1,565), we are unaware of colony changes of
significance to the overall population or of significant impacts to the
emperor penguin's sea-ice or marine habitat. We also found no evidence
that disease, fishery interaction, or oil pollution was affecting a
decline in the emperor penguin population. Based on the best available
data, we find that the identified stressors are not causing a long-term
decline in the emperor penguin's population. Thus, we conclude that the
species is neither threatened nor endangered due to factors causing
ongoing population declines.
We also considered whether any of the stressors began recently
enough that their effects are not yet manifested in a long-term
decline, but are likely to have that effect in the future. As discussed
above, the emperor penguin is an ice-dependent species, and changes in
the physical environment can affect individual colonies. At the current
time, based on the best available scientific evidence, we conclude that
no current directional climatic changes are affecting the habitat of
the emperor penguin, and we do not have sufficient scientific
information to make reliable predictions as to declines of the species
in the foreseeable future. Also, we are unaware of any reports of
diseases in emperor penguins, fishery interactions with juvenile
penguins, or oil spills that have affected emperor penguins. Therefore,
the emperor penguin is neither threatened nor endangered due to threats
that began recently enough that their effects are not yet manifested in
a long-term decline.
Then, we considered whether any of the stressors were likely to
increase within the foreseeable future, such that the species is likely
to become endangered. As explained in greater detail in Factor A,
climate model simulations of winter and summer mean sea-ice
concentrations around Antarctica for the period 2080-2100 project
declines in sea-ice concentrations from those observed in the 1980-2000
timeframe (Bracegirdle et al. 2008, p. 8; Meehl et al. 2007, p. 771).
While these model simulations exhibit extensive deviation around mean
predictions, they provide a general picture of future Antarctic sea-ice
conditions in the range of the emperor penguin. They show winter sea-
ice reductions by 2080-2100, with sea-ice concentrations remaining high
around the bulk of the continent and highest in the Ross, Amundsen, and
Weddell Seas, and around the Mawson Coast in the Indian Ocean sector.
In the 2080-2100 timeframe, summer sea-ice concentrations also retreat,
with sea ice persisting in the Ross and Weddell Seas and apparently
greatly reduced or not persisting in the Indian Ocean sector.
The IPCC, Fourth Assessment Report (IPCC AR4), is very clear on the
limitations of the climate models and their projections (Christenson
2007, p. 908; Randall et al. 2007, p. 616). It is difficult and
premature to use these model results to make specific predictions about
the sea-ice conditions in any particular region of emperor penguin
habitat around Antarctica. This is particularly difficult when
empirical evidence to date suggests that such continent-wide sea-ice
declines have not yet begun. However, considering the species as a
whole, these large-scale model predictions seem to indicate that
emperor penguins, especially in the Ross and Weddell Seas, are likely
to
[[Page 77300]]
continue to encounter suitable sea-ice habitat for breeding in the
winter and molting in the summer in the 100-year timeframe (i.e., 2080-
2100). Therefore, we conclude that there is not sufficient evidence to
find that climate change effects to the habitat of the emperor penguin
are likely to be a threat to the emperor penguin in the foreseeable
future. In addition, as discussed above, disease, fishery interaction
with juveniles, and oil pollution are not likely to increase
significantly in the future.
Next, we considered whether the species met the definition of an
`endangered' or `threatened' species on the basis of its present or
likely future numbers. The total population of 195,000 breeding pairs
appears to be stable, and we are unaware of significant current
declines. The population is widely distributed on the Antarctic
Peninsula and the total number of penguins is not so low that the
species is currently in danger of extinction.
Finally, we considered whether the species is likely to become
endangered in the foreseeable future because stochastic events might
reduce its current numbers to the point where its viability would be in
question. Because this species is distributed in approximately 45
colonies on the Antarctic Peninsula, a future stochastic event that
negatively affected the species would be unlikely to reduce the
population to such a low level that the species would be in danger of
extinction.
On the basis of analysis of the five factors and the best available
scientific and commercial information, we find that the emperor penguin
is not currently threatened or endangered in any portion of its range
or likely to become so in the foreseeable future.
Distinct Population Segment
A discussion of distinct population segments and the Service policy
can be found above in the southern rockhopper penguin Distinct
Population Segment section.
Discreteness Analysis
A discussion of discreteness can be found above in the southern
rockhopper penguin Discreteness Analysis section.
Emperor penguins have a continuous range from Marie Byrd Land east
of the Ross Sea to the Weddell Sea. With respect to discreteness, while
the emperor penguin can be found in three broadly defined areas of
distribution, we are unaware of any marked separation between areas of
abundance of the emperor penguin or of differences in physical,
physiological, ecological, or behavioral factors among any groups
within that range. We are unaware of any research on genetic or
morphological discontinuity between any elements of the population. The
range of the emperor penguin is entirely within the jurisdiction of the
Antarctic Treaty and CCAMLR, except for one area of the Pacific Ocean
where dispersing juveniles may spend some time outside of the CCAMLR
zones. We find no significant differences in conservation status,
habitat management, or regulatory mechanisms between any possible
segment of the emperor penguin population. As a result of this
analysis, we do not find any segments of the population of the emperor
penguin that meet the criterion of discreteness for determination of a
DPS. Therefore, we do not find a DPS for the emperor penguin.
Significant Portion of the Range Analysis
Having determined that the emperor penguin is not now in danger of
extinction or likely to become so in the foreseeable future, we also
considered whether there were any significant portions of its range
where the species is in danger of extinction or likely to become so in
the foreseeable future. See our analysis for the southern rockhopper
penguin for how we make this determination.
First, we examined possible portions of the range that might be
considered significant, and then we considered whether there were any
portions of the range where the threats were different or concentrated
in particular areas. Woehler (1993, p. 5) described three main areas,
each of which encompasses a large area of the Antarctic coast: (1) The
Weddell Sea and Dronning Maud Land; (2) Enderby and Princess Elizabeth
lands; and (3) the Ross Sea. Within these areas, colonies are widely
distributed along the coastline, and each is very isolated from its
nearest neighbors. The area ``between'' these general regions is not a
distinct geographical barrier, but an area where colonies are spread
even more sparsely along the coast. In these areas, there is a longer
distance between the individual colonies or ``links'' in the chain of
colonies encircling most of the continent. During the period of
molting, adult penguins range widely and often into the vicinity of
other colonies. For example, Wienecke et al. (2004, p. 90) inferred
potential mixing at sea between birds from four colonies along the
Mawson Coast and suggested this was a potential vehicle for
interbreeding of birds from different colonies.
In fact, the wider distribution of colonies between ``regions'' may
actually be an artifact of the difficulty of visiting remote areas of
the coast away from the few research stations that exist on the coast
or difficulties of reaching these areas at a time when breeding can be
detected (Kooyman 2002, p. 492). A recent discovery of a new colony
along one of the longest stretches of Wilkes Land led researchers to
predict that more colonies will be found in one of the longest gaps of
recorded colonies. With each confirmed new discovery has come evidence
indicating more colonies may exist. This would provide evidence of
stronger connections between areas (Lea and Soper 2005, pp. 59-60;
Melick and Bremmers 1995, p. 427) and greater potential for mixing or
interbreeding between regions.
In the course of our review, we have discussed the declines that
occurred at the small Cape Crozier and Beaufort Island colonies in the
Western Ross Sea over the period of 2001-2005 as the result of the
impact of iceberg B15A. The most recent data from 2005 indicated that
the Beaufort Island colony had seen significant post-iceberg recovery
in chick counts. After an initial breeding failure in 2001 at Cape
Crozier, the year of iceberg impact, chick counts fluctuated from 247
in 2002, to 333 in 2003, to 475 in 2004, to 0 in 2005, and 340 chicks
in 2006 (Barber-Meyer et al. 2007b, pp. 7, 9). Given the small current
and historic size of these colonies (averaging 526 (Cape Crozier) and
896 (Beaufort Island) chicks over 22 years) and their location in the
vicinity of four other larger emperor penguin colonies in the western
Ross Sea with chick counts averaging from 2,843 (Franklin Island), to
19,776 (Cape Washington), to 23,859 (Coulman Island) and to 6,215 (Cape
Roget) chicks) over the same period, we do not consider these colonies
to represent a significant portion of the range of the emperor penguin.
Finding of Emperor Penguin SPR Analysis
Given the current stability of conditions for the emperor penguin
throughout its range and the paucity of current stressors identified,
we do not find through our five-factor analysis any stressor that has
the potential to affect any one portion of the range of the emperor
penguin differently than any other. With respect to the longer-term
issue of changes in sea-ice cover, we do not find that current models
provide sufficient predictive power to evaluate regional scenarios with
confidence or to make distinctions as to the potential risks to any
particular portion of the
[[Page 77301]]
range. For these reasons, we conclude that there are no portions of the
emperor penguin's range that warrant further consideration as
significant portions of the range.
Final Determination for the Emperor Penguin
On the basis of analysis of the five factors and the best available
scientific and commercial information, we find that listing the emperor
penguin as threatened or endangered under the Act in all or any
significant portion of its range is not warranted.
Public Comments Solicited on the Proposed Rule To List the Southern
Rockhopper Penguin in the Campbell Plateau Portion of Its Range
We intend that any final action resulting from this proposal will
be as accurate and as effective as possible. Therefore, we request
comments or suggestions on this proposed rule. We particularly seek
comments concerning:
(1) Biological, commercial, trade, or other relevant data
concerning any threats (or lack thereof) to this species and
regulations that may be addressing those threats.
(2) Additional information concerning the range, distribution, and
population size of this species, including the locations of any
additional populations of this species.
(3) Any information on the biological or ecological requirements of
the species.
(4) Current or planned activities in the areas occupied by the
species and possible impacts of these activities on this species.
You may submit your comments and materials concerning this proposed
rule by one of the methods listed in the ADDRESSES section. We will not
consider comments sent by e-mail or fax or to an address not listed in
the ADDRESSES section.
If you submit a comment via http://www.regulations.gov, your entire
comment--including any personal identifying information--will be posted
on the website. If you submit a hardcopy comment that includes personal
identifying information, you may request at the top of your document
that we withhold this information from public review. However, we
cannot guarantee that we will be able to do so. We will post all
hardcopy comments on http://www.regulations.gov.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on http://www.regulations.gov, or by
appointment, during normal business hours, at the U.S. Fish and
Wildlife Service, Division of Scientific Authority, 4401 N. Fairfax
Drive, Room 110, Arlington, VA 22203; telephone 703-358-1708.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, requirements for Federal
protection, and prohibitions against certain practices. Recognition
through listing results in public awareness, and encourages and results
in conservation actions by Federal governments, private agencies and
groups, and individuals.
Section 7(a) of the Act, as amended, and as implemented by
regulations at 50 CFR part 402, requires Federal agencies to evaluate
their actions within the United States or on the high seas with respect
to any species that is proposed or listed as endangered or threatened,
and with respect to its critical habitat, if any is being designated.
However, given that the Campbell Plateau portion of the range of the
New Zealand/Australia Distinct Population Segment (DPS) of the southern
rockhopper penguin is not native to the United States, critical habitat
is not being designated for these species under section 4 of the Act.
Section 8(a) of the Act authorizes limited financial assistance for
the development and management of programs that the Secretary of the
Interior determines to be necessary or useful for the conservation of
endangered and threatened species in foreign countries. Sections 8(b)
and 8(c) of the Act authorize the Secretary to encourage conservation
programs for foreign endangered species and to provide assistance for
such programs in the form of personnel and the training of personnel.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered and
threatened wildlife. As such, these prohibitions would be applicable to
the Campbell Plateau portion of the range of the New Zealand/Australia
Distinct Population Segment (DPS) of the southern rockhopper penguin.
These prohibitions, under 50 CFR 17.21, make it illegal for any person
subject to the jurisdiction of the United States to ``take'' (take
includes harass, harm, pursue, hunt, shoot, wound, kill, trap, capture,
collect, or to attempt any of these) within the United States or upon
the high seas, import or export, deliver, receive, carry, transport, or
ship in interstate or foreign commerce in the course of a commercial
activity, or to sell or offer for sale in interstate or foreign
commerce, any endangered wildlife species. It also is illegal to
possess, sell, deliver, carry, transport, or ship any such wildlife
that has been taken in violation of the Act. Certain exceptions apply
to agents of the Service and State conservation agencies.
We may issue permits to carry out otherwise prohibited activities
involving endangered and threatened wildlife species under certain
circumstances. Regulations governing permits are codified at 50 CFR
17.22 for endangered species, and at 17.32 for threatened species. With
regard to endangered wildlife, a permit must be issued for the
following purposes: for scientific purposes, to enhance the propagation
or survival of the species, and for incidental take in connection with
otherwise lawful activities.
Peer Review
In accordance with our joint policy with National Marine Fisheries
Service, ``Notice of Interagency Cooperative Policy for Peer Review in
Endangered Species Act Activities,'' published in the Federal Register
on July 1, 1994 (59 FR 34270), we will seek the expert opinions of at
least three appropriate independent specialists regarding this proposed
rule. The purpose of peer review is to ensure that our proposed rule is
based on scientifically sound data, assumptions, and analyses. We will
send copies of this proposed rule to the peer reviewers immediately
following publication in the Federal Register. We will invite these
peer reviewers to comment during the public comment period, on our
specific assumptions and conclusions regarding this proposed rule.
We will consider all comments and information we receive during the
comment period on this proposed rule during our preparation of a final
determination. Accordingly, our final decision may differ from this
proposal.
Public Hearings
The Act provides for one or more public hearings on this proposal,
if we receive any requests for hearings. We must receive your request
for a public hearing within 45 days after the date of this Federal
Register publication (see DATES). Such requests must be made in writing
and be addressed to the Chief of the Division of Scientific Authority
at the address shown in the FOR FURTHER INFORMATION CONTACT section. We
will schedule public hearings on this proposal, if any are requested,
and announce the dates, times, and places of those hearings, as well as
how to obtain reasonable accommodations, in the
[[Page 77302]]
Federal Register at least 15 days before the first hearing.
Required Determinations
Regulatory Planning and Review (Executive Order 12866)
The Office of Management and Budget has determined that this rule
is not significant under Executive Order 12866.
National Environmental Policy Act (NEPA)
We have determined that environmental assessments and environmental
impact statements, as defined under the authority of the National
Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.), need not be
prepared in connection with regulations adopted under section 4(a) of
the Act. We published a notice outlining our reasons for this
determination in the Federal Register on October 25, 1983 (48 FR
49244).
Clarity of the Rule
We are required by Executive Orders 12866 and 12988, and by the
Presidential Memorandum of June 1, 1998, to write all rules in plain
language. This means that each rule we publish must:
(a) Be logically organized;
(b) Use the active voice to address readers directly;
(c) Use clear language rather than jargon;
(d) Be divided into short sections and sentences; and
(e) Use lists and tables wherever possible.
If you feel that we have not met these requirements, send us
comments by one of the methods listed in the ADDRESSES section. To
better help us revise the rule, your comments should be as specific as
possible. For example, you should tell us the numbers of the sections
or paragraphs that are unclearly written, which sections or sentences
are too long, the sections where you feel lists or tables would be
useful, etc.
References Cited
A complete list of the references cited in this notice is available
on the Internet at http://www.regulations.gov or upon request from the
Division of Scientific Authority, U.S. Fish and Wildlife Service (see
FOR FURTHER INFORMATION CONTACT).
Author
The authors of this proposed rule are staff of the Division of
Scientific Authority, U.S. Fish and Wildlife Service (see FOR FURTHER
INFORMATION CONTACT).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Proposed Regulation Promulgation
Accordingly, we propose to amend part 17, subchapter B of chapter
I, title 50 of the Code of Federal Regulations, as set forth below:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Public Law 99-625, 100 Stat. 3500; unless otherwise
noted.
2. Amend Sec. 17.11(h) by adding a new entry for ``Penguin,
southern rockhopper'' in alphabetical order under BIRDS to the List of
Endangered and Threatened Wildlife as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
-------------------------------------------------------- population where Critical Special
Historic range endangered or Status When listed habitat rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
Birds
* * * * * * *
Penguin, southern rockhopper..... Eudyptes chrysocome. Southern Ocean, New Zealand-- T NA NA
South Atlantic Campbell Plateau.
Ocean, South
Pacific Ocean,
Southern Indian
Ocean.
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * *
Dated: December 2, 2008 .
H. Dale Hall,
Director, U.S. Fish and Wildlife Service.
[FR Doc. E8-29673 Filed 12-17-08; 8:45 am]
BILLING CODE 4310-55-P