By: Nate Edelman
Description and Ecology:
-Terrestrial
-Has a domed shell and round "slightly elephantine hind legs"
-Front legs are flattened for digging and heavily scaled for webbed toes
-Back legs are skinnier and very long
-Small head and rounded in front with reddish-tan coloring
-Front and hind feet are about equal size and the tail is of short length
-Length of about 10-14 inches (25-35 cm)-Height about 4-6 inches (10-15 cm)
- Weight ranges from 11-23 kilograms (24-51 lb.)
-Males slightly larger than females
-Males have larger gular horn (throat) in females
-Males Plastron (lower shell) is concave compared to females
- Live approximately 50-80 years
- Have a slow and low reproductive rates
- Can tolerate water, salt, and energy imbalances on a daily basis, which increases their lifespan
-Herbivore
-Eats herbs, annual wildflowers, cacti, fruit, flowers
Geographic and Population Changes:
- Specifically distributed in western Arizona, southeastern California, southern Nevada, and southwestern Utah
- Spend most of the time in burrows, rock shelters, and pallets to regulate body temperature and reduce water loss
-Most active after seasonal rains are are inactive during most of the year
Listing date and Type of Listing:
-Date listed: 5/6/2011
-Plan stage: RF (Revision Approved. First plan was in 1994. Final Revision approved by the Regional Director)
-Listed as: Threatened
Cause of listing and Main threats to its Continued Existence:
The most significant threats include urbanization, disease, habitat destruction, fragmentation, illegal collection and vandalism (by humans).
-95% of the tortoise's life is spent in the ground escaping the heat or a burrow. Burrows can easily be crushed by off-highway vehicles that do not stay on established roads.-Non-native Sahara mustard (a type of weed) can grow so dense that it is impossible for tortoises to pass through
-Threatened by several diseases such as the upper respiratory tract disease often found in captive tortoises. Pet owners that release sick tortoises in the wild can cause this problem.-Trash can be mistaken for food. Can give tortoises a false sense of food and a false sense of fullness that may cause them to starve
-Natural predators: Ravens, gila monsters, badgers, roadrunners, coyotes, fire ants
-Prey on eggs
Description of Recovery Plan (according to the U.S. Fish and Wildlife Service):
1. Develop, Support, and Build Partnerships to Facilitate Recovery
-Establish Recovery Implementation Teams
2. Protect Existing Populations and Habitat
-Conserve intact habitat
-Minimize factors contributing to disease
-Establish/Continue environmental education programs
-Increase law enforcement
-Sign and fence boundaries of sensitive or impacted areas
-Minimize excessive predation
-Minimize impacts from horse and burros, and from livestock grazing.
3. Augment Depleted Populations through a Strategic Program
-Develop protocols and guidelines for the population augmentation program
-Identify sites and secure facilities for use of augmentation
4. Monitor progress toward Recovery
- Monitor tortoise population growth and distribution
- Conduct research on desert tortoise diseases
5. Conduct applied research and modeling in support of recovery efforts within a strategic framework
- Determine factors that influence the distribution and conduct research on the restoration
-Improve models of threats, threat mitigation, and desert tortoise habitat
6. Implement an Adaptive Management Program
- Revise and continue development and recovery support system
-Amend land use plans, habitat management plans, and other plans needed to implement
-Incorporate scientific advice for recovery through the Science Advisory Committee
Total Estimated Cost of Recovery:
$159,000,000 plus additional costs yet to be determined
Date of Recovery:
The current monitoring program which began in 2001, recovery criteria could be met by approximately 2025.
Sources: http://www.fws.gov/endangered/species/recovery-plans.html
http://ecos.fws.gov/tess_public/pub/speciesRecovery.jsp?sort=2
http://www.endangeredspeciesinternational.org/deserttortoise.html
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