[Federal Register Volume 61, Number 42 (Friday, March 1, 1996)]
[Proposed Rules]
[Pages 8018-8019]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-4804]
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DEPARTMENT OF THE INTERIOR
50 CFR Part 17
Endangered and Threatened Wildlife and Plants: 12-Month Finding
for a Petition To List the Amargosa Toad (Bufo nelsoni) as Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of 12-month petition finding.
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SUMMARY: The Fish and Wildlife Service (Service) announces a 12-month
finding on a petition to list the Amargosa toad (Bufo nelsoni) as an
endangered species under the Endangered Species Act of 1973, as amended
(Act). After review of all available scientific and commercial
information concerning the status of the species, the Service finds
that listing of the Amargosa toad is not warranted.
DATES: The finding announced in this document was made on November 9,
1995.
ADDRESSES: Data, information, comments, or questions concerning this
notice should be submitted to the State Supervisor, U.S. Fish and
Wildlife Service, Nevada State Office, 4600 Kietzke Lane, Building C-
125, Reno, Nevada 89502. The petition, findings, and supporting data
are available for public inspection, by appointment, during normal
business hours at the above address.
FOR FURTHER INFORMATION CONTACT:
Donna Withers, Staff Biologist, at the above address, or telephone
(702) 784-5227.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(B) of the Endangered Species Act of 1973, as
amended (Act) (16 U.S.C. 1531 et seq.), requires that for any petition
to revise the Lists of Endangered and Threatened Wildlife and Plants
that contains substantial scientific or commercial information, a
finding be made within 12 months of the date of receipt of the petition
on whether the petitioned action is (a) not warranted, (b) warranted,
or (c) warranted but precluded from immediate proposal by other pending
proposals. Such 12-month findings are to be published promptly in the
Federal Register.
On September 21, 1994, the Service received a petition dated
September 19, 1994, to emergency list the Amargosa toad (Bufo nelsoni)
as an endangered species. The Service's finding that substantial
information existed indicating the petitioned action may be warranted
was published in the Federal Register on March 17, 1995 (60 FR 15280).
A status review was initiated at that time.
The Amargosa toad has been identified as either a category 1 or
category 2 species under the Act, since December 30, 1982 (47 FR 58454;
50 FR 37958; 59 FR 58982). The Amargosa toad was a category 1 candidate
species with a listing priority of 2 at the time the petition was
received by the Service. On July 26, 1995, the Service recommended
removal of the Amargosa toad from category 1 candidate status based
information obtained during the 1995 status review. The information
suggested that the Amargosa toad is more widespread and abundant within
the Oasis Valley than previous reports indicated. However, additional
information is necessary to adequately determine the status of the
species, and conservation efforts have been initiated to remove
identified threats.
The Amargosa toad is unique to riparian habitats associated with
the Amargosa River, tributary springs of the Amargosa River in Oasis
Valley and isolated spring systems near Beatty, Nye County, Nevada. The
petition stated that the Amargosa toad was restricted to seven sites
within Oasis Valley, and two isolated spring systems, and that these
sites are impacted by livestock and feral burro grazing, water
diversion, flood control activities, off-road vehicle use, and
nonnative species introductions. The petition stated that the Amargosa
toad had declined from thousands in 1958 to only 30 individuals in
1994.
Amargosa toads were first collected in 1891 from an unidentified
location in Oasis Valley (Stejneger 1893). Between 1931 and 1981,
Amargosa toads were observed at only three sites within Oasis Valley
and at one isolated spring system, despite intensive searches (Linsdale
1940, Savage 1959, Altig 1981, Altig and Dodd 1987). Thousands of
Amargosa toads were observed in June 1958 (Savage 1959). The Amargosa
toad was considered severely restricted in distribution and threatened
by habitat destruction by 1981 (Altig 1981).
During a 1983 survey, Amargosa toads were observed at 11 sites
within Oasis Valley and two isolated spring systems, and assumed
present at 14 additional sites, based on statements from area residents
and suitability of habitat, even though toads were not observed
(Maciolek 1983a, 1983b). Amargosa toad, though restricted to the Oasis
Valley and vicinity, was considered well distributed and abundant in
1983 (Maciolek 1983b).
Amargosa toad surveys have been conducted at 20 sites since 1990,
but not all sites were visited during each survey or with equal
frequency (Hoff 1993, 1994a, 1994b; Clemmer 1995; Heinrich 1995).
Available data from the sites surveyed since 1990 suggests that
Amargosa toads have been extirpated from one spring and are not as
abundant as in previous years at four other springs (Savage 1959; Altig
1981; Maciolek 1983a, 1983b; Hoff 1993; Hoff 1994a, 1994b; Clemmer
1995; Heinrich 1995). At the other 15 sites, however, observations of
Amargosa toad adults, juveniles, tadpoles, and eggs have fluctuated but
remained relatively constant, and the occurrence of eggs or tadpoles at
sites where no adults were observed implies the presence of adults.
Estimates of the size of the adult population of Amargosa toads
during 1993 and 1994 vary from 30 toads for each year to 130 and 85
toads for the 2 years, respectively (Hoff 1994a, 1994b; Heinrich 1995).
Both estimates were based on direct observations of Amargosa toad
adults, juveniles, tadpoles, and egg masses at the same ten sites. The
disparity between these estimates may be due to the difficulty inherent
in adequately surveying for Amargosa toads.
The available information does not support the petitioner's claim
that the Amargosa toad population is severely restricted in both
abundance and distribution. Comprehensive Amargosa toad status
information is unavailable because not all historically identified
habitats have been surveyed since 1983. Information from Oasis Valley
residents suggests that Amargosa toads still occupy springs on several
private properties not surveyed in recent years.
[[Page 8019]]
A comprehensive evaluation of the status and distribution of Amargosa
toad will only be possible when additional surveys are conducted in
potential amphibian habitat with Oasis Valley.
Habitats occupied by Amargosa toads are subject to various natural
and human-induced modifications resulting from flooding, flood-control
and restoration activities, nonnative species introductions, livestock
and feral burro grazing, off-road vehicle use, and release of
pollutants (Altig 1981, Maciolek 1983a, Hoff 1994b). The information on
the release of pollutants is anecdotal. Voluntary conservation
activities have been recently initiated to address these threats to
Amargosa toads and their habitats. These activities will provide a
sound foundation for appropriate management of Amargosa toad habitats.
The petitioner acknowledged the existence of these conservation
activities, but questioned their effectiveness. The conservation
activities initiated to date have only been in place a short time, and
additional time is necessary for the benefits of these actions to be
realized.
The Nevada Division of Wildlife (NDOW) and Nevada Natural Heritage
Program have conducted status surveys and undertaken conservation
activities, including initiation of cooperative agreements with
involved agencies and local governments and conservation agreements
with private landowners. The Bureau of Land Management (BLM) actively
manages the public lands occupied by Amargosa toad for the conservation
of the species. BLM has restricted off-road vehicle use in or near
Amargosa toad habitat, constructed enclosure fences to eliminate damage
to riparian habitats from feral burro and livestock use, proposed all
occupied habitats as Areas of Critical Environmental Concern, and
initiated a cadastral survey of the Amargosa River in Oasis Valley to
establish property boundaries. The Nature Conservancy (TNC) has been
working with the Beatty Beautification Committee toward development of
a park along the Amargosa River or a pond area which would provide
recreational opportunities for the residents, and attract tourists, as
well as create or conserve Amargosa toad habitat. TNC is currently
negotiating the purchase of two private properties that contain
Amargosa toad habitat. The Nye County Department of Public Works has
agreed to notify NDOW prior to any activity within the Amargosa River
channel to avoid impacts to the Amargosa toad. Owners of two private
properties with Amargosa toad habitat on their land have initiated
conservation activities.
After reviewing all scientific and commercial information
available, the Service has determined that listing the Amargosa toad is
not warranted at this time. This decision is based on information
contained in the petition, received during the status review, and
otherwise available to the Service at the time the 12-month finding was
made, which indicates that the Amargosa toad is more widespread and
abundant within the Oasis Valley than stated in the petition. In
addition, conservation efforts have been initiated to remove identified
threats. The Service recognizes the need to monitor the species' status
to determine Amargosa toad population trends and measure the
effectiveness of the conservation measures.
References Cited
A list of references cited is available from the Nevada State
Office (see Addresses section above).
Author: The primary author of this document is Donna Withers
(see ADDRESSES section above).
Authority
The authority for this action is the Endangered Species Act of
1973, as amended (16 U.S.C. 531 et seq.).
Dated: November 9, 1995.
Mollie H. Beattie,
Director, Fish and Wildlife Service.
[FR Doc. 96-4804 Filed 2-29-96; 8:45 am]
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