[Federal Register: August 4, 2008 (Volume 73, Number 150)]
[Page 45236-45238]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

[FWS-R8-ES-2008-N0114; 80221-1113-0000-C2]

Draft Revised Recovery Plan for Mojave Population of the Desert 
Tortoise (Gopherus agassizii)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of document availability for review and comment.


SUMMARY: We, U.S. Fish and Wildlife Service (Service), announce the 
availability of a draft revised recovery plan for the Mojave population 
of the desert tortoise for public review and comment.

DATES: We must receive any comments on the draft recovery plan on or 
before November 3, 2008.

ADDRESSES: The draft recovery plan and reference materials are 
available for inspection, by appointment, during normal business hours 
at the following location: U.S. Fish and Wildlife Service, Nevada Fish 
and Wildlife Office, 1340

[[Page 45237]]

Financial Boulevard, Suite 234, Reno, NV 89502 (telephone: 775-861-
6300). Submitted comments regarding the draft revised recovery plan 
will also be available for public inspection, by appointment, during 
normal business hours following the public review and comment period. 
Requests for copies of the draft revised recovery plan and submission 
of written comments or materials regarding the plan should be addressed 
to the Field Supervisor at the above address. You may also submit 
electronic comments on the recovery plan to: DTrecovery@fws.gov. An 
electronic copy of the draft recovery plan is available at: http://

FOR FURTHER INFORMATION CONTACT: Roy Averill-Murray, Desert Tortoise 
Recovery Coordinator, at the above address or telephone number.



    Recovery of endangered or threatened animals and plants is a 
primary goal of the Endangered Species Act (Act) (16 U.S.C. 1531 et 
seq. ) and our endangered species program. Recovery means improvement 
of the status of listed species to the point at which listing is no 
longer required under the criteria set out in section 4(a)(1) of the 
Act. Recovery plans describe actions considered necessary for the 
conservation of the species, establish criteria for downlisting or 
delisting listed species, and estimate time and cost for implementing 
the measures needed for recovery. The Recovery Plan for the Mojave 
Population of the Desert Tortoise (Gopherus agassizii) was first 
published in 1994 wherein the status of the species, threats, recovery 
actions and recovery criteria were presented. Since that time a great 
deal of effort has been dedicated to recovery and conservation 
activities, and additional information has been obtained through 
research and observation that allows us to better focus our recovery 
strategy. The revised recovery plan for the Mojave Population of the 
desert tortoise is the focus of this notice.
    Section 4(f) of the Act directs the Secretaries of Interior and 
Commerce to develop and implement recovery plans for species listed as 
endangered or threatened, unless such plans will not promote the 
conservation of the species. We and the National Marine Fisheries 
Service, as appropriate, have been delegated responsibility for 
administering the Act. Section 4(f) of the Act requires that public 
notice, and an opportunity for public review and comment, be provided 
during development of recovery plans. We will consider all information 
presented during the public comment period on each new or revised 
recovery plan. Substantive comments may or may not result in changes to 
a recovery plan. However, any substantive comments regarding recovery 
plan implementation will be forwarded to appropriate Federal agencies 
or other interested entities so that they can take these comments into 
account during the implementation of their respective management 
programs. Individual responses to submitted comments will not be 
    The desert tortoise is a large, herbivorous reptile that can reach 
20 to 38 centimeters (cm) (8 to 15 inches (in)) in carapace length and 
10 to 15 cm (4 to 6 in) in shell height. Hatchlings emerge from eggs at 
about 5 cm (2 in) in length. Adults have a domed carapace and 
relatively flat, unhinged plastrons (lower shells). Their shells are 
high-domed and greenish-tan to dark brown in color with tan scute 
(horny plate on the shell) centers. Adult desert tortoises weigh 3.6 to 
6.8 kilograms (8 to 15 pounds). The forelimbs have heavy, claw-like 
scales and are flattened for digging. Hind limbs are more elephantine.
    Throughout most of the Mojave Desert, the desert tortoise occupies 
a variety of habitats: From flats and slopes dominated by creosote bush 
(Larrea tridentata) scrub at lower elevations, to rocky slopes in the 
blackbrush (Coleogyne ramosissima) scrub, and juniper (Juniperus spp.) 
woodland interface at higher elevations. Records of desert tortoises 
range from below sea level to an elevation of 2,225 meters (m) (7,300 
feet (ft)), with the most favorable habitat at elevations between 305 
and 914 m (1,000 and 3,000 ft). Desert tortoises most commonly occur on 
gently sloping terrain with sandy-gravel soils that are friable for 
burrowing and where there is sparse cover of low-growing shrubs and a 
high diversity of both perennial and annual plants.
    The desert tortoise occurs in the Mojave and Sonoran deserts in 
southern California, southern Nevada, Arizona, and the southwestern tip 
of Utah in the United States, as well as in Sonora and northern Sinaloa 
in Mexico. The listed Mojave population of the desert tortoise includes 
those animals living north and west of the Colorado River in the Mojave 
Desert of California, Nevada, Arizona, and southwestern Utah, and in 
the Sonoran (Colorado) Desert in California. A recovery plan was 
published in 1994 and critical habitat was also designated in all four 
States supporting the species.
    Three other tortoise species in the genus Gopherus occur in the 
United States, and another occurs in Mexico; however, all are 
geographically separated from the Mojave population. The Sonoran 
population of the desert tortoise is significantly different both 
genetically and ecologically, but could be confused visually with 
tortoises of the Mojave population; therefore, we determined the 
Sonoran population also warranted protection as a threatened species 
under section 4(e) of the Endangered Species Act (similarity of 
appearance) when located outside of its natural range.
    The vast majority of threats to the desert tortoise or its habitat 
are associated with human land uses. The threats identified in the 1994 
Recovery Plan, and that formed the basis for listing the tortoise as a 
threatened species, continue to affect the species. Habitat loss, 
degradation, and fragmentation from urbanization, off-highway vehicle 
use in the desert, linear features such as roads and utility corridors, 
livestock grazing and mining, and military activities were cited as 
some of the primary reasons for the decline in desert tortoise 
populations. Disease and increased incidence of fire in the Mojave 
Desert have also been implicated in desert tortoise declines.
    The data amassed between 1979 and 2002 from permanent study plots 
throughout the range of the species were used to explore regional and 
recovery-unit-level analyses and trends, and to develop within-
population spatial analyses at various scales on the landscape and in 
different management units. Despite the challenges in comparing data 
from year to year, the apparent downward trend in desert tortoise 
populations in the western portion of the range that was identified at 
the time of listing is considered ongoing. Results from other portions 
of the range were inconclusive, but recent surveys of some populations 
found too few tortoises to produce population estimates, suggesting 
that declines may have occurred more broadly.
    Collectively, the various analyses that have been performed do not 
suggest that implementation of specific management actions over time 
has abated declines of, or resulted in detectable increases in, desert 
tortoise populations across most of the range. The life history of the 
species (i.e., delayed reproductive maturity, low reproductive rates, 
and relatively high mortality early in life) is such that observing 
relatively rapid increases in populations is highly unlikely, even over 
the 23-year monitoring period evaluated.

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    Despite the clear demonstration that the threats identified at the 
time of listing impact individual tortoises, there are few data 
available to evaluate or quantify the effects of threats on desert 
tortoise populations. While current research results can lead to 
predictions about how local tortoise abundance should be affected by 
the presence of threats, quantitative estimates of the magnitude of 
these threats, or of their relative importance, have not yet been 
    While precise correlations between the multitude of threats and 
desert tortoise populations have not been clearly shown, a great deal 
of effort has been put forth by research scientists and land managers 
to actively conserve the species. Substantive datasets pertaining to 
disease, non-native invasive plant species, and fire have been 
assembled over the years that will be used to inform decisions relative 
to desert tortoise recovery. Conservation actions such as land 
acquisitions, installing protective fencing, retiring grazing 
allotments, limiting off-highway vehicle access, and implementing 
restoration projects have been important recovery and management 
efforts based on our current state of knowledge regarding the threats 
facing the species.
    The revised strategy emphasizes partnerships to direct and maintain 
focus on implementing recovery actions and a system to track 
implementation and effectiveness of those actions. The strategic 
elements listed herein are part of a multi-faceted approach designed to 
improve the 1994 Recovery Plan. The goals of the revised recovery plan 
are recovery and delisting of the desert tortoise. The objectives and 
recovery criteria address demography (maintain self-sustaining 
populations of desert tortoises within each recovery unit into the 
future); distribution (maintain well-distributed populations of desert 
tortoises throughout each recovery unit); and habitat (ensure that 
habitat within each recovery unit is protected and managed to support 
long-term viability of desert tortoise populations. The strategic 
elements include the following: (1) Develop, support, and build 
partnerships to facilitate recovery; (2) protect existing populations 
and habitat, instituting habitat restoration where necessary; (3) 
augment depleted populations in a strategic, experimental manner; (4) 
monitor progress toward recovery, includes population trend and 
effectiveness monitoring; (5) conduct applied research and modeling in 
support of recovery efforts within a strategic framework; and (6) 
implement a formal adaptive management program that integrates new 
information and utilizes conceptual models that link management actions 
to predicted responses by desert tortoise populations or their habitat. 
The success of this revised recovery strategy will rely heavily upon 
the involvement of our partners and our commitment to implementing the 
strategic elements listed above coupled with a functioning adaptive 
management program.

Public Comments Solicited

    We solicit written comments on the draft revised recovery plan 
described in this notice. All comments received by the date specified 
above will be considered in development of a final revised recovery 
plan for the Mojave population of the desert tortoise.

    Authority: The authority for this action is section 4(f) of the 
Endangered Species Act, 16 U.S.C. 1533(f).

Jim A. Bartel,
Acting Regional Director, Region 8, U.S. Fish and Wildlife Service.
[FR Doc. E8-17520 Filed 8-1-08; 8:45 am]