Endangered and Threatened Wildlife and Plants; Revised 12-Month Finding for the Southern Rocky Mountain Distinct Population Segment of the Boreal Toad (Bufo boreas boreas, 56880-56884 [05-19488]
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Federal Register / Vol. 70, No. 188 / Thursday, September 29, 2005 / Proposed Rules
§ 117.618
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Authority: 33 U.S.C. 499; Department of
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Dated: September 18, 2005.
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[FR Doc. 05–19583 Filed 9–27–05; 12:13 pm]
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DEPARTMENT OF THE INTERIOR
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ACTION: Proposed rule.
Fish and Wildlife Service
SUMMARY: EPA proposes to approve the
Clean Air Act (CAA) section 111(d)/129
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Endangered and Threatened Wildlife
and Plants; Revised 12-Month Finding
for the Southern Rocky Mountain
Distinct Population Segment of the
Boreal Toad (Bufo boreas boreas)
AGENCY:
Environment
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50 CFR Part 17
Fish and Wildlife Service,
Interior.
ACTION: Notice of revised 12-month
finding for the Southern Rocky
Mountain Distinct Population Segment
of the Boreal Toad.
AGENCY:
SUMMARY: We, the Fish and Wildlife
Service (Service), announce our revised
12-month finding for a petition to list
the Southern Rocky Mountain
population (SRMP) of the boreal toad
(Bufo boreas boreas) as endangered
under the Endangered Species Act
(ESA). After a review of the best
available scientific and commercial
information, we find that listing is not
warranted at this time because the
SRMP of the boreal toad does not
constitute a species, subspecies, or
distinct population segment (DPS)
under the ESA. Therefore, we withdraw
the SRMP from the candidate list. The
Service will continue to seek new
information on the taxonomy, biology,
and ecology of these toads, as well as
potential threats to their continued
existence.
DATES: This finding was made on
September 20, 2005. Although no
further action will result from this
finding, we request that you submit new
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information concerning the taxonomy,
biology, ecology, and status of the SRMP
or other populations of the subspecies,
as well as potential threats to their
continued existence, whenever it
becomes available.
ADDRESSES: The complete file for this
finding is available for inspection, by
appointment, during normal business
hours, at the U.S. Fish and Wildlife
Service Ecological Services Field Office,
764 Horizon Drive, Building B, Grand
Junction, Colorado 81506–3946. Submit
new information, materials, comments,
or questions concerning this species to
us at the above address.
FOR FURTHER INFORMATION CONTACT:
Allan Pfister, Western Colorado
Supervisor, at the address listed above,
by telephone at 970–243–2778,
extension 29, by facsimile at 970–245–
6933, or by e-mail al_pfister@fws.gov.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(B) of the ESA requires
that within 12 months after receiving a
petition to revise the List of Endangered
and Threatened Wildlife that contains
substantial information indicating that
the petitioned action may be warranted,
the Secretary shall make one of the
following findings: the petitioned action
is not warranted, the petitioned action
is warranted, or the petitioned action is
warranted but precluded by other
pending proposals of higher priority.
Such 12-month findings are to be
published promptly in the Federal
Register. The ESA also requires that
when a warranted but precluded finding
is made, a petition is treated as
resubmitted and the Service is required
to publish a new petition finding on an
annual basis.
On September 30, 1993, the Service
received a petition from the Biodiversity
Legal Foundation, Boulder, Colorado,
and Dr. Peter Hovingh, a researcher at
the University of Utah, Salt Lake City,
Utah. The petitioners requested that the
Service list the SRMP of the ‘‘western
boreal toad’’ (Bufo boreas boreas) as
endangered throughout its range in
northern New Mexico, Colorado, and
southern Wyoming, as well as designate
critical habitat in all occupied areas and
in the key unoccupied areas where
restoration is necessary. A notice of a
90-day finding for the petition was
published in the Federal Register on
July 22, 1994 (59 FR 37439), indicating
that the petition and other readily
available scientific and commercial
information presented substantial
information that the petitioned action
may be warranted.
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In 1994, a Boreal Toad Recovery Team
(Team) was formed of agency
representatives from the Service,
Colorado Division of Wildlife, Wyoming
Game and Fish Department, New
Mexico Department of Game and Fish,
National Park Service, U.S. Geological
Survey, U.S. Environmental Protection
Agency, U.S. Forest Service, and U.S.
Bureau of Land Management, along with
technical advisors from several
universities and other interested parties.
The Team produced a recovery plan for
the boreal toad in Colorado, a draft
Conservation Strategy, and a draft
Conservation Agreement; in 1998,
components of these documents were
combined in the production of the
Boreal Toad Conservation Plan, which
has since been revised (Loeffler 2001).
Management activities guided by the
Team include annual monitoring of
known breeding populations; research
of factors limiting toad survival;
research of toad habitat, biology, and
ecology; captive breeding and rearing
techniques and protocols; experimental
reintroductions of toads to vacant
historic habitat; coordination with land
management agencies, land use
planners, and developers to protect the
boreal toad and its habitats; and efforts
to increase public education and
awareness of the subspecies.
On March 23, 1995, the Service
announced a 12-month finding that
listing the SRMP of the boreal toad
(Bufo boreas boreas) as an endangered
species was warranted but precluded by
other higher priority actions (60 FR
15281). When we find that a petition to
list a species is warranted but
precluded, we refer to it as a candidate
for listing. Section 4(b)(3)(B) of the ESA
directs that, when we make a
‘‘warranted but precluded’’ finding on a
petition, we are to treat the petition as
being one that is resubmitted annually
on the date of the finding; thus the ESA
requires us to reassess the petitioned
actions and to publish a finding on the
resubmitted petition on an annual basis.
Several candidate assessments for the
boreal toad have been completed; these
are available for viewing online at http:
//www.fws.gov/endangered/candidates/
index.html. The most recent assessment
was published in the Federal Register
May 11, 2005 (70 FR 24870).
In our most recent Notice of Findings
on Resubmitted Petitions, we noted that
a proposed listing determination for the
boreal toad would be funded in Fiscal
Year 2005 (70 FR 24870, May 11, 2005).
This resubmitted 12-month finding
evaluates new information and reevaluates previously acquired
information. In accordance with section
4(b)(3)(B) of the ESA, we have now
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completed a status review of the best
available scientific and commercial
information on the species, and have
reached a determination regarding the
petitioned action.
Species Information
The western toad (Bufo boreas) is an
amphibian that occurs throughout much
of the western United States. The
species was first described by Baird and
Girard (1852). Camp (1917) considered
two forms as subspecies, the boreal toad
(B. b. boreas) and the California toad (B.
b. halophilus). Stebbins (1985)
recognizes these two subspecies.
Crother et al. (2003) note the general
recognition of two nominal subspecies
(B. b. boreas and B. b. halophilus), with
the Amargosa toad (B. b. nelsoni)
sometimes recognized as a third
subspecies. Stebbins (1985) considers
the Amargosa toad (Bufo nelsoni) to be
a distinct species. The geographic
variation within Bufo boreas is poorly
studied and may mask a number of
cryptic species (Crother et al. 2003).
Recent DNA (deoxyribonucleic acid)
analyses suggest a taxonomic change to
the complex may be warranted (Goebel
1996).
The range of the boreal toad
subspecies (B. b. boreas) is coastal
Alaska south through British Columbia,
western Alberta, Washington, Oregon,
northern California, western and central
Nevada, Idaho, western Montana,
western and south central Wyoming, the
mountains of Utah and Colorado, and
extreme northern New Mexico. The
range of the California toad subspecies
(B. b. halophilus) is northern California
south to the Baja peninsula of Mexico,
and east to western Nevada. The ranges
of the California toad and the boreal
toad overlap in northern California
(Stebbins 1985). The SRMP of the boreal
toad (B. b. boreas) is the segment of the
subspecies that is the focus of this
finding, and refers to the toads
occurring within the southern Rocky
Mountain physiographic province. This
region extends from south central
Wyoming, throughout the mountainous
portions of Colorado, and into extreme
northern New Mexico.
Boreal toads in the SRMP may reach
a length (snout to vent) of 11
centimeters (4 inches) (Hammerson
1999). They possess warty skin, oval
parotid glands, and often have a
distinctive light mid-dorsal stripe.
During the breeding season, males
develop a dark patch on the inner
surface of the innermost digit. Unlike
other Bufo species, the boreal toad has
no vocal sac and, therefore, no mating
call (Hammerson 1999). Tadpoles are
black or dark brown. The eggs are black
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and are deposited in long double layer
jelly strings with one to three rows of
eggs (Hammerson 1999).
In the southern Rocky Mountains,
adult boreal toads emerge from winter
refugia when snowmelt has cleared an
opening from their burrows and daily
temperatures remain above freezing
(Campbell 1970a, b). Breeding occurs
during a 2- to 4-week period from midMay to mid-June at lower elevations,
and as late as mid-July at higher
elevations (Hammerson 1999). Suitable
breeding sites are large bodies of water
or small pools, beaver ponds, glacial
kettle ponds, roadside ditches, humanmade ponds, and slow-moving streams
(Campbell 1970a; Hammerson 1999).
Females lay up to 16,500 eggs in 2
strings, which ordinarily are deposited
in shallow water (Stebbins 1954). Carey
et al. (2005) reported an overall mean
clutch size of 6,661 eggs for 3
populations studied in Colorado. Eggs
hatch 1 to 2 weeks after being laid. Egg
and tadpole development is
temperature-dependent, and
reproductive efforts may fail if tadpoles
do not have sufficient time to
metamorphose before the onset of
winter. Persistent, shallow bodies of
water are critical to breeding success,
and if the breeding site dries before
metamorphosis is complete, desiccation
of the tadpoles or eggs will occur.
Tadpoles typically metamorphose by
late July to late August, but at higher
elevations metamorphosis may not be
complete until late September (Loeffler
2001). Recently metamorphosed toadlets
aggregate within a few meters of the
water, and move into nearby moist
habitats later in summer. After mating,
adults often disperse to upland,
terrestrial habitats, where they are
mostly diurnally active in early and late
summer (Mullally 1958; Campbell
1970a; Carey 1978), foraging primarily
on ants, beetles, spiders, and other
invertebrates (Schonberger 1945;
Campbell 1970a). Late in the summer
home ranges will expand, generally in
the direction of wintering habitats
(Campbell 1970a), which include
cavities among streamside boulders,
ground squirrel burrows, and beaver
lodges and dams (Hammerson 1999).
Survival of embryos from laying to
hatching is normally high but
catastrophic mortality has been
observed (Blaustein and Olson 1991).
Survival of tadpoles and juveniles is
very low, with predation and adverse
environmental conditions primarily
responsible for mortality at these life
stages (Campbell 1970a). Samollow
(1980) estimated that 95 to 99 percent
die before reaching their second year of
life. The minimum age of breeding
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boreal toads in Colorado is about 4 years
in males and 6 years in females
(Hammerson 1999). Olson (1991) found
that females may skip 1 to 3 years
between breeding attempts. Individuals
may live approximately 11 or 12 years
(Olson 1991).
Distinct Vertebrate Population Segment
Pursuant to the ESA, we must
consider for listing any species,
subspecies, or, for vertebrates, any DPS
of these taxa if there is sufficient
information to indicate that such action
may be warranted. To interpret and
implement the DPS provision of the
ESA and congressional guidance, the
Service and the National Marine
Fisheries Service published, on
December 21, 1994, a draft Policy
Regarding the Recognition of Distinct
Vertebrate Population Segments Under
the ESA and invited public comments
on it (59 FR 65885). After review of
comments and further consideration,
the Services adopted the interagency
policy as issued in draft form, and
published it in the Federal Register on
February 7, 1996 (61 FR 4722). This
policy addresses the recognition of DPSs
for potential listing actions. The policy
allows for more refined application of
the ESA that better reflects the
biological needs of the taxon being
considered, and avoids the inclusion of
entities that do not require its protective
measures.
Under our DPS policy, three elements
are considered in a decision regarding
the status of a possible DPS as
endangered or threatened under the
ESA. These are applied similarly for
additions to the list of endangered and
threatened species, reclassification, and
removal from the list. They are:
discreteness of the population segment
in relation to the remainder of the taxon;
the significance of the population
segment to the taxon to which it
belongs; and the population segment’s
conservation status in relation to the
ESA’s standards for listing (i.e., is the
population segment, when treated as if
it were a species, endangered or
threatened?). Discreteness refers to the
isolation of a population from other
members of the species and we evaluate
this based on specific criteria. If a
population segment is considered
discrete, the Service must consider
whether the discrete segment is
‘‘significant’’ to the taxon to which it
belongs. We determine significance by
using the best available scientific
information to determine the DPS’s
importance to the taxon to which it
belongs. If we determine that a
population segment is discrete and
significant, we then evaluate it for
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endangered or threatened status based
on the ESA’s standards. The DPS
evaluation in this finding concerns the
SRMP segment of the boreal toad
subspecies (B. b. boreas), occurring
within the southern Rocky Mountain
physiographic province extending from
south central Wyoming through the
mountainous portions of Colorado and
into extreme northern New Mexico.
Discreteness
Under our DPS Policy, a population
segment of a vertebrate species may be
considered discrete if it satisfies either
one of the following conditions: 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
it is delimited by international
governmental boundaries within which
differences in control of exploitation,
management of habitat, conservation
status, or regulatory mechanisms exist
that are significant in light of section
4(a)(1)(D) of the ESA. The SRMP meets
the first condition for the following
reasons:
Based on evidence of feasible
dispersal distances, the SRMP is
geographically (physically) separated
from other populations of the boreal
toad (Keinath and McGee 2005). The
greatest recorded distance of movement
for a boreal toad in the southern Rocky
Mountains is 8 kilometers (5 miles)
(Lambert 2003) and most movements are
smaller (Bartelt 2000; Jones 2000; Muths
2003). Southern Wyoming toads (within
the SRMP) are separated from the
northern Wyoming populations (outside
the SRMP) by approximately 160
kilometers (100 miles) of dry, nonforested valleys and basins of the Red
Desert (Keinath and McGee 2005). The
boreal toad has never been observed in
the Red Desert, and its highest
elevations (2,000 m (6,562 ft)) are below
the lowest elevation (2,300 m (7,546 ft))
of boreal toad occurrences in Wyoming.
The habitat in riparian areas along rivers
at these lower elevations is warmer,
drier, and composed of much different
vegetation, creating a barrier to
migrating boreal toads (Keinath and
McGee 2005). The large size and arid,
inhospitable habitat make the Red
Desert impassible for migrating toads.
The SRMP also is geographically
separated from other boreal toad
populations to the west. Over 250
kilometers (155 miles) of arid habitat
exists in eastern Utah and northwestern
Colorado, physically separating the
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SRMP from the Utah populations in the
Wasatch and Uinta Mountains.
Morphological differences between
toads of the SRMP and other boreal toad
populations provide evidence of the
geographic separation of the SRMP.
Burger and Bragg (1947) noted several
morphological differences between
adults collected in Colorado and the
Pacific Northwest, including differences
in body length, skin coloration and
texture, head proportion, and parotid
gland shape and position. In the former,
the dorsal coloration is darker and the
skin between the warts is smoother and
less pronounced. In the Colorado toads,
the parotid gland is more oblong and
less elevated, ventral markings are more
numerous and irregular, and the head is
proportionately larger and broader. The
maximum length of the Colorado toads
was 8.3 centimeters (3.3 inches)
compared with 12.5 centimeters (4.9
inches) in the Pacific Northwest toads
(Burger and Bragg 1947). However, these
observations were based on cursory
examination of a few specimens from
one Colorado geographic area, and many
more specimens and observations of the
boreal toad throughout its range were
deemed necessary to clarify the status of
the Colorado toads (Burger and Bragg
1947). Hubbard (1972) also noted
morphological differences between
boreal toads in Colorado and British
Columbia, Canada, as well as behavioral
and biochemical differences. British
Columbia toads were observed to
possess much brighter and more
variable coloration, and a smaller
parotid gland than Colorado specimens;
the distress call of toads in Colorado did
not have a decrease in frequency of
terminal segments of harmonics, which
toads in British Columbia possess; and
a serum protein analysis indicated toads
from British Columbia have greater
proportions of alpha-2 globulin and
albumin and less alpha-1 globulin than
those from Colorado (Hubbard 1972).
However, comparisons of these
characters within and between several
additional boreal toad populations
would be necessary to further
substantiate the distinctiveness of toads
in Colorado and the remainder of the
SRMP.
Based on its current geographic
(physical) separation from other boreal
toad populations, and some
morphological and genetic differences,
we conclude the SRMP meets the
definition of discreteness under our DPS
policy.
Significance
If a population segment is determined
to be discrete, the Service considers the
available scientific evidence of its
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significance to the taxon to which it
belongs. Our policy states that this
consideration may include, but is not
limited to, the following:
(1) Persistence of the discrete
population segment in an ecological
setting unusual or unique for the taxon;
(2) Evidence that loss of the discrete
population segment would result in a
significant gap in the range of the taxon;
(3) Evidence that the discrete
population segment represents the only
surviving natural occurrence of a taxon
that may be more abundant elsewhere as
an introduced population outside its
historical range; or
(4) Evidence that the discrete
population segment 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.
Persistence of the Discrete Population
Segment in an Ecological Setting
Unusual or Unique for the Taxon —The
boreal toad occurs from the Rocky
Mountains to the Pacific Coast.
Throughout its range, the subspecies
shows an unusual plasticity in its
choice of habitats (Campbell 1970a). In
the SRMP, toads inhabit montane
wetland habitats and adjacent uplands
near suitable breeding habitats. These
are ecological settings similar to those
used by populations of the boreal toad
outside the SRMP, in the montane
regions of northern Wyoming, Idaho,
Utah, Montana, and other western
states. Generally speaking, in the higher
latitudes of its range suitable boreal toad
habitats may be found at lower
elevations. We do not find that the
SRMP persists in an ecological setting
unusual or unique for the subspecies.
Loss Would Represent a Significant
Gap in the Range of the Taxon—Loss of
the SRMP would reduce the range of B.
b. boreas at its southeastern-most
extension, from south central Wyoming,
through the mountainous regions of
Colorado, and into extreme northern
New Mexico. The remaining range
would extend from coastal Alaska south
through British Columbia, western
Alberta, Washington, Oregon, northern
California, western and central Nevada,
Idaho, western Montana, Utah, and
western Wyoming. Due to the broad
geographic range of B. b. boreas across
the western United States, the gap
resulting from loss of the SRMP would
be a relatively small proportion of the
overall subspecies range and not
significant.
Our analysis used the currently
accepted taxonomy and range
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determinations for the parent taxon (the
B. b. boreas subspecies) and the
population segment under consideration
(the SRMP). At this time, uncertainty
exists with regard to the taxonomy of
the Bufo boreas complex, including the
designation of a single boreal toad
subspecies, the distinctness of the
SRMP segment, and the taxonomic
status of other population segments in
the Rocky Mountains. The geographic
variation within Bufo boreas is poorly
studied, and this lack of information is
thought to mask the existence of other
species (Crother et al. 2003). The results
from phylogenetic analyses of the Bufo
boreas group confirm this uncertainty,
as they suggest the existence of
evolutionary lineages inconsistent with
the current taxonomy (Goebel 1996,
2005).
If new taxonomic information
becomes available that could change our
analysis, we will reconsider our
decision. However, based on the best
available information, we cannot
conclude at this time that loss of the
SRMP would represent a significant gap
in the range of the subspecies.
The Only Surviving Natural
Occurrence of a Taxon—This criterion
from the DPS policy does not apply
because the SRMP of the boreal toad is
clearly not a ‘‘population segment
representing the only surviving natural
occurrence of a taxon that may be more
abundant elsewhere as an introduced
population outside its historic range.’’ If
this situation changes or new
information becomes available, we will
reconsider our decision.
Evidence that the SRMP Differs
Markedly from Other Populations in
Genetic Characteristics—In our
consideration of ‘‘significance,’’ the
Service must evaluate evidence to
determine whether the SRMP differs
markedly from other populations
belonging to the currently recognized
subspecies, B. b. boreas. Information
from mitochondrial DNA data (Goebel
1996, 1999, 2000, 2003, 2005) and
nuclear DNA data (Goebel 1999, 2000,
2003) suggests that boreal toads of the
SRMP differ genetically from other
populations, but the differences
between the SRMP and toads in central
and northern Utah, southeastern Idaho,
and western Wyoming are small, not
well resolved, and based on small
sample sizes.
A notable result of the mitochondrial
DNA studies is that, in each study,
specimens sampled from the SRMP
cluster within the same
phylogeographic clade, which is a group
considered to be of common
evolutionary origin. However, the
specimens from the SRMP did not form
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56884
Federal Register / Vol. 70, No. 188 / Thursday, September 29, 2005 / Proposed Rules
a monophyletic clade; depending on the
study or analysis method, specimens
from northern Utah, central Utah, and
western Wyoming group with the SRMP
(Goebel 1996, 1999, 2000, 2003, 2005).
The lack of observed monophyly may be
due to poor resolution that additional
samples and sequence data might
improve (Goebel 1999, 2000). It may
also suggest that toads in the SRMP are
very closely related to nearby
populations due to recent (in geologic
time) geographic isolation of the SRMP
(Goebel 1999). While the current
mitochondrial DNA data suggest the
existence of diverging evolutionary
lineages in the Bufo boreas group, the
toads appear to be so closely related that
interbreeding would likely produce
viable offspring (Goebel 2003).
The close relationships between the
SRMP and nearby populations may also
be due to the retention of ‘‘old’’
haplotypes from lineage sorting (Goebel
1999, 2000). From a phylogenetic
viewpoint the entire mitochondrial
DNA genome constitutes a single locus
inherited as a linked unit (Avise 2000).
Therefore, analyses based on the
mitochondrial genome could produce
patterns that represent the gene’s
lineage, but not necessarily the true
evolutionary direction of the species.
For this reason, when analyzing the
historical relationships among taxa it is
prudent to compare phylogenetic
hypotheses from both mitochondrial
data and nuclear data (which represent
a large number of loci).
Studies of the Bufo boreas group
using nuclear DNA data have been
performed, but the results were affected
by small sample sizes from some
localities and exclusion of samples due
to missing data (Goebel 1999, 2000).
When later analyses were performed
with additional samples, a nuclear DNA
clade containing the SRMP was
identified, but it included specimens
from western Wyoming localities
geographically separated from the SRMP
(Goebel 2003).
We believe that additional nuclear
(e.g. micro satellite) DNA data and
supplemental mitochondrial DNA
sequence data are necessary to clarify
the genetic relationships within and
between boreal toad populations,
including the SRMP segment and others
in the Rocky Mountains. The multiagency Team also recommends
additional studies, on the grounds that
genetic distinctions between SRMP
toads and nearby toad populations are
based on data from too few specimens
(Loeffler 2001). After considering the
best available information, we cannot
conclude that the SRMP differs
VerDate Aug<31>2005
15:11 Sep 28, 2005
Jkt 205001
markedly from other boreal toad
populations in genetic characteristics.
In conclusion, we determine that the
SRMP, as currently described, does not
meet the significance criteria of our DPS
policy. As such, the SRMP does not
qualify as a distinct population segment.
Therefore, it is not a listable entity
under the ESA. Based on this
determination, we withdraw the SRMP
from the candidate list.
We will accept additional information
and comments from all concerned
governmental agencies, the scientific
community, industry, or any other
interested party concerning this finding.
We will reconsider this determination
in the event that new information
indicates that the SRMP is significant.
References
A complete list of all references cited
herein is available upon request from
the Grand Junction, Colorado Office,
U.S. Fish and Wildlife Service (see
ADDRESSES).
Author
The primary author of this finding is
Larry Thompson, Grand Junction,
Colorado Office, U.S. Fish and Wildlife
Service (see ADDRESSES).
Authority: The authority for this action is
the Endangered Species Act of 1973 (16
U.S.C. 1531 et seq.).
Dated: September 20, 2005.
Marshall P. Jones, Jr.,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 05–19488 Filed 9–28–05; 8:45 am]
BILLING CODE 4310–55–P
DEPARTMENT OF COMMERCE
National Oceanic and Atmospheric
Administration
50 CFR Part 224
[I.D. 081605A]
Endangered and Threatened Species;
Petition to Initiate Emergency
Rulemaking to Prevent the Extinction
of the North Atlantic Right Whale; Final
Determination
National Marine Fisheries
Service (NMFS), National Oceanic and
Atmospheric Administration (NOAA),
Commerce.
ACTION: Notice; response to petition;
final determination.
AGENCY:
SUMMARY: NMFS received a petition
dated May 19, 2005 co-signed by
Defenders of Wildlife, International
Fund for Animal Welfare, International
Wildlife Coalition, National
Environmental Trust, Natural Resources
PO 00000
Frm 00027
Fmt 4702
Sfmt 4702
Defense Council, Oceana, The Humane
Society of the United States, The Ocean
Conservancy, and Whale and Dolphin
Conservation Society, requesting that
NMFS ‘‘promulgate emergency
regulations, within sixty days, to slow
and/or re-route vessels within right
whale habitat, as a means of protecting
the species until such time as
permanent measures can be enacted.
Such emergency regulations should
require all ships entering and leaving all
major East Coast ports to travel at
speeds of 12 knots or less within 25
nautical miles of port entrances during
expected right whale high-use periods.’’
NMFS has determined that the petition
is not warranted at this time.
ADDRESSES: Further information on the
North Atlantic Right Whale program can
be found on NMFS’ internet websites at
www.nmfs.noaa.gov/pr/shipstrike/ and
at www.nero.noaa.gov/shipstrike/.
Comments and requests for copies of
this determination should be addressed
to the Chief, Marine Mammal and Turtle
Conservation Division, Office of
Protected Resources, NMFS, 1315 EastWest Highway, Silver Spring, MD
20910.
FOR FURTHER INFORMATION CONTACT: P.
Michael Payne; Phone: 301–713–2322;
Fax: 301–427–2522.
SUPPLEMENTARY INFORMATION:
Background
The North Atlantic right whale,
Eubalaena glacialis, is considered one
of the most endangered large whale
populations in the world. Right whales
have been listed as endangered under
the Endangered Species Act (ESA) since
its passage in 1973 (35 FR 8495, June 2,
1970). Although precise estimates of
abundance are not available, it appears
that the eastern North Atlantic
population is nearly extinct and the
western North Atlantic population
numbers approximately 300 whales.
The status of North Atlantic right
whales is a very serious issue for NMFS.
While calf production has increased
somewhat in recent years, recovery is
seriously affected by fatalities and
serious injury resulting from human
activities, primarily from entanglement
in fishing gear and collisions with ships.
NMFS has been working with state
and other Federal agencies, concerned
citizens and citizen groups,
environmental organizations, and the
shipping industry to address the
ongoing threat of ship strikes to North
Atlantic right whales as part of its
responsibilities related to right whale
recovery. NMFS has established a right
whale ship strike reduction program,
that includes among other things, aerial
E:\FR\FM\29SEP1.SGM
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]]>Agencies
[Federal Register Volume 70, Number 188 (Thursday, September 29, 2005)]
[Proposed Rules]
[Pages 56880-56884]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-19488]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Revised 12-Month
Finding for the Southern Rocky Mountain Distinct Population Segment of
the Boreal Toad (Bufo boreas boreas)
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of revised 12-month finding for the Southern Rocky
Mountain Distinct Population Segment of the Boreal Toad.
-----------------------------------------------------------------------
SUMMARY: We, the Fish and Wildlife Service (Service), announce our
revised 12-month finding for a petition to list the Southern Rocky
Mountain population (SRMP) of the boreal toad (Bufo boreas boreas) as
endangered under the Endangered Species Act (ESA). After a review of
the best available scientific and commercial information, we find that
listing is not warranted at this time because the SRMP of the boreal
toad does not constitute a species, subspecies, or distinct population
segment (DPS) under the ESA. Therefore, we withdraw the SRMP from the
candidate list. The Service will continue to seek new information on
the taxonomy, biology, and ecology of these toads, as well as potential
threats to their continued existence.
DATES: This finding was made on September 20, 2005. Although no further
action will result from this finding, we request that you submit new
[[Page 56881]]
information concerning the taxonomy, biology, ecology, and status of
the SRMP or other populations of the subspecies, as well as potential
threats to their continued existence, whenever it becomes available.
ADDRESSES: The complete file for this finding is available for
inspection, by appointment, during normal business hours, at the U.S.
Fish and Wildlife Service Ecological Services Field Office, 764 Horizon
Drive, Building B, Grand Junction, Colorado 81506-3946. Submit new
information, materials, comments, or questions concerning this species
to us at the above address.
FOR FURTHER INFORMATION CONTACT: Allan Pfister, Western Colorado
Supervisor, at the address listed above, by telephone at 970-243-2778,
extension 29, by facsimile at 970-245-6933, or by e-mail al_
pfister@fws.gov.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(B) of the ESA requires that within 12 months after
receiving a petition to revise the List of Endangered and Threatened
Wildlife that contains substantial information indicating that the
petitioned action may be warranted, the Secretary shall make one of the
following findings: the petitioned action is not warranted, the
petitioned action is warranted, or the petitioned action is warranted
but precluded by other pending proposals of higher priority. Such 12-
month findings are to be published promptly in the Federal Register.
The ESA also requires that when a warranted but precluded finding is
made, a petition is treated as resubmitted and the Service is required
to publish a new petition finding on an annual basis.
On September 30, 1993, the Service received a petition from the
Biodiversity Legal Foundation, Boulder, Colorado, and Dr. Peter
Hovingh, a researcher at the University of Utah, Salt Lake City, Utah.
The petitioners requested that the Service list the SRMP of the
``western boreal toad'' (Bufo boreas boreas) as endangered throughout
its range in northern New Mexico, Colorado, and southern Wyoming, as
well as designate critical habitat in all occupied areas and in the key
unoccupied areas where restoration is necessary. A notice of a 90-day
finding for the petition was published in the Federal Register on July
22, 1994 (59 FR 37439), indicating that the petition and other readily
available scientific and commercial information presented substantial
information that the petitioned action may be warranted.
In 1994, a Boreal Toad Recovery Team (Team) was formed of agency
representatives from the Service, Colorado Division of Wildlife,
Wyoming Game and Fish Department, New Mexico Department of Game and
Fish, National Park Service, U.S. Geological Survey, U.S. Environmental
Protection Agency, U.S. Forest Service, and U.S. Bureau of Land
Management, along with technical advisors from several universities and
other interested parties. The Team produced a recovery plan for the
boreal toad in Colorado, a draft Conservation Strategy, and a draft
Conservation Agreement; in 1998, components of these documents were
combined in the production of the Boreal Toad Conservation Plan, which
has since been revised (Loeffler 2001). Management activities guided by
the Team include annual monitoring of known breeding populations;
research of factors limiting toad survival; research of toad habitat,
biology, and ecology; captive breeding and rearing techniques and
protocols; experimental reintroductions of toads to vacant historic
habitat; coordination with land management agencies, land use planners,
and developers to protect the boreal toad and its habitats; and efforts
to increase public education and awareness of the subspecies.
On March 23, 1995, the Service announced a 12-month finding that
listing the SRMP of the boreal toad (Bufo boreas boreas) as an
endangered species was warranted but precluded by other higher priority
actions (60 FR 15281). When we find that a petition to list a species
is warranted but precluded, we refer to it as a candidate for listing.
Section 4(b)(3)(B) of the ESA directs that, when we make a ``warranted
but precluded'' finding on a petition, we are to treat the petition as
being one that is resubmitted annually on the date of the finding; thus
the ESA requires us to reassess the petitioned actions and to publish a
finding on the resubmitted petition on an annual basis. Several
candidate assessments for the boreal toad have been completed; these
are available for viewing online at http: //www.fws.gov/endangered/
candidates/. The most recent assessment was published in the
Federal Register May 11, 2005 (70 FR 24870).
In our most recent Notice of Findings on Resubmitted Petitions, we
noted that a proposed listing determination for the boreal toad would
be funded in Fiscal Year 2005 (70 FR 24870, May 11, 2005). This
resubmitted 12-month finding evaluates new information and re-evaluates
previously acquired information. In accordance with section 4(b)(3)(B)
of the ESA, we have now completed a status review of the best available
scientific and commercial information on the species, and have reached
a determination regarding the petitioned action.
Species Information
The western toad (Bufo boreas) is an amphibian that occurs
throughout much of the western United States. The species was first
described by Baird and Girard (1852). Camp (1917) considered two forms
as subspecies, the boreal toad (B. b. boreas) and the California toad
(B. b. halophilus). Stebbins (1985) recognizes these two subspecies.
Crother et al. (2003) note the general recognition of two nominal
subspecies (B. b. boreas and B. b. halophilus), with the Amargosa toad
(B. b. nelsoni) sometimes recognized as a third subspecies. Stebbins
(1985) considers the Amargosa toad (Bufo nelsoni) to be a distinct
species. The geographic variation within Bufo boreas is poorly studied
and may mask a number of cryptic species (Crother et al. 2003). Recent
DNA (deoxyribonucleic acid) analyses suggest a taxonomic change to the
complex may be warranted (Goebel 1996).
The range of the boreal toad subspecies (B. b. boreas) is coastal
Alaska south through British Columbia, western Alberta, Washington,
Oregon, northern California, western and central Nevada, Idaho, western
Montana, western and south central Wyoming, the mountains of Utah and
Colorado, and extreme northern New Mexico. The range of the California
toad subspecies (B. b. halophilus) is northern California south to the
Baja peninsula of Mexico, and east to western Nevada. The ranges of the
California toad and the boreal toad overlap in northern California
(Stebbins 1985). The SRMP of the boreal toad (B. b. boreas) is the
segment of the subspecies that is the focus of this finding, and refers
to the toads occurring within the southern Rocky Mountain physiographic
province. This region extends from south central Wyoming, throughout
the mountainous portions of Colorado, and into extreme northern New
Mexico.
Boreal toads in the SRMP may reach a length (snout to vent) of 11
centimeters (4 inches) (Hammerson 1999). They possess warty skin, oval
parotid glands, and often have a distinctive light mid-dorsal stripe.
During the breeding season, males develop a dark patch on the inner
surface of the innermost digit. Unlike other Bufo species, the boreal
toad has no vocal sac and, therefore, no mating call (Hammerson 1999).
Tadpoles are black or dark brown. The eggs are black
[[Page 56882]]
and are deposited in long double layer jelly strings with one to three
rows of eggs (Hammerson 1999).
In the southern Rocky Mountains, adult boreal toads emerge from
winter refugia when snowmelt has cleared an opening from their burrows
and daily temperatures remain above freezing (Campbell 1970a, b).
Breeding occurs during a 2- to 4-week period from mid-May to mid-June
at lower elevations, and as late as mid-July at higher elevations
(Hammerson 1999). Suitable breeding sites are large bodies of water or
small pools, beaver ponds, glacial kettle ponds, roadside ditches,
human-made ponds, and slow-moving streams (Campbell 1970a; Hammerson
1999).
Females lay up to 16,500 eggs in 2 strings, which ordinarily are
deposited in shallow water (Stebbins 1954). Carey et al. (2005)
reported an overall mean clutch size of 6,661 eggs for 3 populations
studied in Colorado. Eggs hatch 1 to 2 weeks after being laid. Egg and
tadpole development is temperature-dependent, and reproductive efforts
may fail if tadpoles do not have sufficient time to metamorphose before
the onset of winter. Persistent, shallow bodies of water are critical
to breeding success, and if the breeding site dries before
metamorphosis is complete, desiccation of the tadpoles or eggs will
occur. Tadpoles typically metamorphose by late July to late August, but
at higher elevations metamorphosis may not be complete until late
September (Loeffler 2001). Recently metamorphosed toadlets aggregate
within a few meters of the water, and move into nearby moist habitats
later in summer. After mating, adults often disperse to upland,
terrestrial habitats, where they are mostly diurnally active in early
and late summer (Mullally 1958; Campbell 1970a; Carey 1978), foraging
primarily on ants, beetles, spiders, and other invertebrates
(Schonberger 1945; Campbell 1970a). Late in the summer home ranges will
expand, generally in the direction of wintering habitats (Campbell
1970a), which include cavities among streamside boulders, ground
squirrel burrows, and beaver lodges and dams (Hammerson 1999).
Survival of embryos from laying to hatching is normally high but
catastrophic mortality has been observed (Blaustein and Olson 1991).
Survival of tadpoles and juveniles is very low, with predation and
adverse environmental conditions primarily responsible for mortality at
these life stages (Campbell 1970a). Samollow (1980) estimated that 95
to 99 percent die before reaching their second year of life. The
minimum age of breeding boreal toads in Colorado is about 4 years in
males and 6 years in females (Hammerson 1999). Olson (1991) found that
females may skip 1 to 3 years between breeding attempts. Individuals
may live approximately 11 or 12 years (Olson 1991).
Distinct Vertebrate Population Segment
Pursuant to the ESA, we must consider for listing any species,
subspecies, or, for vertebrates, any DPS of these taxa if there is
sufficient information to indicate that such action may be warranted.
To interpret and implement the DPS provision of the ESA and
congressional guidance, the Service and the National Marine Fisheries
Service published, on December 21, 1994, a draft Policy Regarding the
Recognition of Distinct Vertebrate Population Segments Under the ESA
and invited public comments on it (59 FR 65885). After review of
comments and further consideration, the Services adopted the
interagency policy as issued in draft form, and published it in the
Federal Register on February 7, 1996 (61 FR 4722). This policy
addresses the recognition of DPSs for potential listing actions. The
policy allows for more refined application of the ESA that better
reflects the biological needs of the taxon being considered, and avoids
the inclusion of entities that do not require its protective measures.
Under our DPS policy, three elements are considered in a decision
regarding the status of a possible DPS as endangered or threatened
under the ESA. These are applied similarly for additions to the list of
endangered and threatened species, reclassification, and removal from
the list. They are: discreteness of the population segment in relation
to the remainder of the taxon; the significance of the population
segment to the taxon to which it belongs; and the population segment's
conservation status in relation to the ESA's standards for listing
(i.e., is the population segment, when treated as if it were a species,
endangered or threatened?). Discreteness refers to the isolation of a
population from other members of the species and we evaluate this based
on specific criteria. If a population segment is considered discrete,
the Service must consider whether the discrete segment is
``significant'' to the taxon to which it belongs. We determine
significance by using the best available scientific information to
determine the DPS's importance to the taxon to which it belongs. If we
determine that a population segment is discrete and significant, we
then evaluate it for endangered or threatened status based on the ESA's
standards. The DPS evaluation in this finding concerns the SRMP segment
of the boreal toad subspecies (B. b. boreas), occurring within the
southern Rocky Mountain physiographic province extending from south
central Wyoming through the mountainous portions of Colorado and into
extreme northern New Mexico.
Discreteness
Under our DPS Policy, a population segment of a vertebrate species
may be considered discrete if it satisfies either one of the following
conditions: 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 it is
delimited by international governmental boundaries within which
differences in control of exploitation, management of habitat,
conservation status, or regulatory mechanisms exist that are
significant in light of section 4(a)(1)(D) of the ESA. The SRMP meets
the first condition for the following reasons:
Based on evidence of feasible dispersal distances, the SRMP is
geographically (physically) separated from other populations of the
boreal toad (Keinath and McGee 2005). The greatest recorded distance of
movement for a boreal toad in the southern Rocky Mountains is 8
kilometers (5 miles) (Lambert 2003) and most movements are smaller
(Bartelt 2000; Jones 2000; Muths 2003). Southern Wyoming toads (within
the SRMP) are separated from the northern Wyoming populations (outside
the SRMP) by approximately 160 kilometers (100 miles) of dry, non-
forested valleys and basins of the Red Desert (Keinath and McGee 2005).
The boreal toad has never been observed in the Red Desert, and its
highest elevations (2,000 m (6,562 ft)) are below the lowest elevation
(2,300 m (7,546 ft)) of boreal toad occurrences in Wyoming. The habitat
in riparian areas along rivers at these lower elevations is warmer,
drier, and composed of much different vegetation, creating a barrier to
migrating boreal toads (Keinath and McGee 2005). The large size and
arid, inhospitable habitat make the Red Desert impassible for migrating
toads. The SRMP also is geographically separated from other boreal toad
populations to the west. Over 250 kilometers (155 miles) of arid
habitat exists in eastern Utah and northwestern Colorado, physically
separating the
[[Page 56883]]
SRMP from the Utah populations in the Wasatch and Uinta Mountains.
Morphological differences between toads of the SRMP and other
boreal toad populations provide evidence of the geographic separation
of the SRMP. Burger and Bragg (1947) noted several morphological
differences between adults collected in Colorado and the Pacific
Northwest, including differences in body length, skin coloration and
texture, head proportion, and parotid gland shape and position. In the
former, the dorsal coloration is darker and the skin between the warts
is smoother and less pronounced. In the Colorado toads, the parotid
gland is more oblong and less elevated, ventral markings are more
numerous and irregular, and the head is proportionately larger and
broader. The maximum length of the Colorado toads was 8.3 centimeters
(3.3 inches) compared with 12.5 centimeters (4.9 inches) in the Pacific
Northwest toads (Burger and Bragg 1947). However, these observations
were based on cursory examination of a few specimens from one Colorado
geographic area, and many more specimens and observations of the boreal
toad throughout its range were deemed necessary to clarify the status
of the Colorado toads (Burger and Bragg 1947). Hubbard (1972) also
noted morphological differences between boreal toads in Colorado and
British Columbia, Canada, as well as behavioral and biochemical
differences. British Columbia toads were observed to possess much
brighter and more variable coloration, and a smaller parotid gland than
Colorado specimens; the distress call of toads in Colorado did not have
a decrease in frequency of terminal segments of harmonics, which toads
in British Columbia possess; and a serum protein analysis indicated
toads from British Columbia have greater proportions of alpha-2
globulin and albumin and less alpha-1 globulin than those from Colorado
(Hubbard 1972). However, comparisons of these characters within and
between several additional boreal toad populations would be necessary
to further substantiate the distinctiveness of toads in Colorado and
the remainder of the SRMP.
Based on its current geographic (physical) separation from other
boreal toad populations, and some morphological and genetic
differences, we conclude the SRMP meets the definition of discreteness
under our DPS policy.
Significance
If a population segment is determined to be discrete, the Service
considers the available scientific evidence of its significance to the
taxon to which it belongs. Our policy states that this consideration
may include, but is not limited to, the following:
(1) Persistence of the discrete population segment in an ecological
setting unusual or unique for the taxon;
(2) Evidence that loss of the discrete population segment would
result in a significant gap in the range of the taxon;
(3) Evidence that the discrete population segment represents the
only surviving natural occurrence of a taxon that may be more abundant
elsewhere as an introduced population outside its historical range; or
(4) Evidence that the discrete population segment 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.
Persistence of the Discrete Population Segment in an Ecological
Setting Unusual or Unique for the Taxon --The boreal toad occurs from
the Rocky Mountains to the Pacific Coast. Throughout its range, the
subspecies shows an unusual plasticity in its choice of habitats
(Campbell 1970a). In the SRMP, toads inhabit montane wetland habitats
and adjacent uplands near suitable breeding habitats. These are
ecological settings similar to those used by populations of the boreal
toad outside the SRMP, in the montane regions of northern Wyoming,
Idaho, Utah, Montana, and other western states. Generally speaking, in
the higher latitudes of its range suitable boreal toad habitats may be
found at lower elevations. We do not find that the SRMP persists in an
ecological setting unusual or unique for the subspecies.
Loss Would Represent a Significant Gap in the Range of the Taxon--
Loss of the SRMP would reduce the range of B. b. boreas at its
southeastern-most extension, from south central Wyoming, through the
mountainous regions of Colorado, and into extreme northern New Mexico.
The remaining range would extend from coastal Alaska south through
British Columbia, western Alberta, Washington, Oregon, northern
California, western and central Nevada, Idaho, western Montana, Utah,
and western Wyoming. Due to the broad geographic range of B. b. boreas
across the western United States, the gap resulting from loss of the
SRMP would be a relatively small proportion of the overall subspecies
range and not significant.
Our analysis used the currently accepted taxonomy and range
determinations for the parent taxon (the B. b. boreas subspecies) and
the population segment under consideration (the SRMP). At this time,
uncertainty exists with regard to the taxonomy of the Bufo boreas
complex, including the designation of a single boreal toad subspecies,
the distinctness of the SRMP segment, and the taxonomic status of other
population segments in the Rocky Mountains. The geographic variation
within Bufo boreas is poorly studied, and this lack of information is
thought to mask the existence of other species (Crother et al. 2003).
The results from phylogenetic analyses of the Bufo boreas group confirm
this uncertainty, as they suggest the existence of evolutionary
lineages inconsistent with the current taxonomy (Goebel 1996, 2005).
If new taxonomic information becomes available that could change
our analysis, we will reconsider our decision. However, based on the
best available information, we cannot conclude at this time that loss
of the SRMP would represent a significant gap in the range of the
subspecies.
The Only Surviving Natural Occurrence of a Taxon--This criterion
from the DPS policy does not apply because the SRMP of the boreal toad
is clearly not a ``population segment representing the only surviving
natural occurrence of a taxon that may be more abundant elsewhere as an
introduced population outside its historic range.'' If this situation
changes or new information becomes available, we will reconsider our
decision.
Evidence that the SRMP Differs Markedly from Other Populations in
Genetic Characteristics--In our consideration of ``significance,'' the
Service must evaluate evidence to determine whether the SRMP differs
markedly from other populations belonging to the currently recognized
subspecies, B. b. boreas. Information from mitochondrial DNA data
(Goebel 1996, 1999, 2000, 2003, 2005) and nuclear DNA data (Goebel
1999, 2000, 2003) suggests that boreal toads of the SRMP differ
genetically from other populations, but the differences between the
SRMP and toads in central and northern Utah, southeastern Idaho, and
western Wyoming are small, not well resolved, and based on small sample
sizes.
A notable result of the mitochondrial DNA studies is that, in each
study, specimens sampled from the SRMP cluster within the same
phylogeographic clade, which is a group considered to be of common
evolutionary origin. However, the specimens from the SRMP did not form
[[Page 56884]]
a monophyletic clade; depending on the study or analysis method,
specimens from northern Utah, central Utah, and western Wyoming group
with the SRMP (Goebel 1996, 1999, 2000, 2003, 2005). The lack of
observed monophyly may be due to poor resolution that additional
samples and sequence data might improve (Goebel 1999, 2000). It may
also suggest that toads in the SRMP are very closely related to nearby
populations due to recent (in geologic time) geographic isolation of
the SRMP (Goebel 1999). While the current mitochondrial DNA data
suggest the existence of diverging evolutionary lineages in the Bufo
boreas group, the toads appear to be so closely related that
interbreeding would likely produce viable offspring (Goebel 2003).
The close relationships between the SRMP and nearby populations may
also be due to the retention of ``old'' haplotypes from lineage sorting
(Goebel 1999, 2000). From a phylogenetic viewpoint the entire
mitochondrial DNA genome constitutes a single locus inherited as a
linked unit (Avise 2000). Therefore, analyses based on the
mitochondrial genome could produce patterns that represent the gene's
lineage, but not necessarily the true evolutionary direction of the
species. For this reason, when analyzing the historical relationships
among taxa it is prudent to compare phylogenetic hypotheses from both
mitochondrial data and nuclear data (which represent a large number of
loci).
Studies of the Bufo boreas group using nuclear DNA data have been
performed, but the results were affected by small sample sizes from
some localities and exclusion of samples due to missing data (Goebel
1999, 2000). When later analyses were performed with additional
samples, a nuclear DNA clade containing the SRMP was identified, but it
included specimens from western Wyoming localities geographically
separated from the SRMP (Goebel 2003).
We believe that additional nuclear (e.g. micro satellite) DNA data
and supplemental mitochondrial DNA sequence data are necessary to
clarify the genetic relationships within and between boreal toad
populations, including the SRMP segment and others in the Rocky
Mountains. The multi-agency Team also recommends additional studies, on
the grounds that genetic distinctions between SRMP toads and nearby
toad populations are based on data from too few specimens (Loeffler
2001). After considering the best available information, we cannot
conclude that the SRMP differs markedly from other boreal toad
populations in genetic characteristics.
In conclusion, we determine that the SRMP, as currently described,
does not meet the significance criteria of our DPS policy. As such, the
SRMP does not qualify as a distinct population segment. Therefore, it
is not a listable entity under the ESA. Based on this determination, we
withdraw the SRMP from the candidate list.
We will accept additional information and comments from all
concerned governmental agencies, the scientific community, industry, or
any other interested party concerning this finding. We will reconsider
this determination in the event that new information indicates that the
SRMP is significant.
References
A complete list of all references cited herein is available upon
request from the Grand Junction, Colorado Office, U.S. Fish and
Wildlife Service (see ADDRESSES).
Author
The primary author of this finding is Larry Thompson, Grand
Junction, Colorado Office, U.S. Fish and Wildlife Service (see
ADDRESSES).
Authority: The authority for this action is the Endangered
Species Act of 1973 (16 U.S.C. 1531 et seq.).
Dated: September 20, 2005.
Marshall P. Jones, Jr.,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 05-19488 Filed 9-28-05; 8:45 am]
BILLING CODE 4310-55-P
