U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
|California Desert District|
BLM Field Offices:
Desert tortoises have existed for millions of years, and during that time they adapted to the many climatic and geological changes that have occurred in southern California. They can live in many types of desert habitats, but they do require friable (crumbly) soils in order to build burrows and nests. They are most common in desert areas with an abundance of creosote, and they are least common in desert areas with steep slopes. Tortoises are most active between March and June. In late summer the temperatures become too warm and they spend the majority of their time in their burrows. Desert tortoises are very sensitive to the heat, and exposure to the extreme desert temperatures can kill them in less than one hour. They hibernate during the winter months.
Desert tortoises are herbivorous. They eat a variety of desert plants, although forbs and green vegetation are their preferred foods. They will drink water if it is available, but they get some of the water they need for survival from the plants they eat.
The breeding season occurs from April - July, starting shortly after the tortoises emerge from hibernation. Females lay one to three clutches of about five eggs each. The eggs hatch three to four months later. During dry years, some desert tortoises fail to reproduce due to lack of food.
Adult tortoises have very few predators due to their protective carapace. Adults are preyed upon by coyotes and golden eagles. Young tortoises are more vulnerable and are preyed upon by eagles, foxes, and coyotes. In captivity, many tortoises fall victim to an upper respiratory disease. Many human-related activities, discussed below, have resulted in declines of this species, and subsequently, the listing of this species as both federally threatened and state threatened.
BLM's efforts to help this animal
Many desert tortoise populations experiencing serious declines. One cause for this decline is an upper respiratory disease. This disease is usually found in captive pet tortoises, but some pet owners have released their sick tortoises into the wild. As a result, some wild tortoises have contracted and spread the disease. Raven predation on the young has also increased. In addition to these causes, many tortoises have been collected illegally and human activities have destroyed much of their native habitat.
The Bureau of Land Management (BLM) has joined with other organizations such as the U.S. Fish and Wildlife Service and the Desert Tortoise Preservation Committee in an effort to help this species. BLM employees work to uphold the provisions of the Endangered Species Act. Under this Act, listed species may not be harmed, harassed, pursued, hunted, wounded, killed, trapped, or collected. In 1976, the BLM and the Desert Tortoise Preservation Committee formed the Desert Tortoise Natural Area. This area is fenced off and is closed to all recreational activities except wildlife viewing. Three nature trails were created to allow visitors to view the tortoises without disrupting the entire area.
The public can help the recovery of this species in a variety of ways. First, when visiting the Desert Tortoise Natural Area, remember to stay on the trails. Use binoculars to view these incredible animals if they are far away. This area was created to preserve the natural habitat. Second, when visiting the desert be aware of your surroundings. Desert tortoises seek shade in hot weather, and they occasionally find shade under a parked car. Desert tortoises have also been spotted crossing roads, so drive carefully. For more information on desert tortoises, including information about having them as pets, please click on the Desert Tortoise Info. link below.
Behler et al. 1979. National Audubon Society Field Guide to Reptiles and Amphibians.
Carl H. Ernst, Jeffrey E. Lovich and Roger Barbour. 1994. Turtles of the United States and Canada. Smithsonian Institution Press, Washington, D.C. 578pp.
Stebbins 1985. Peterson Field Guide to Western Reptiles and
Zeiner et al. (editors). 1988. California's Wildlife, Volume I, Amphibians
SOME DOs and DON'TS
1. If you find a tortoise in the desert, DO take pictures, get down and look at it (but not so close that you disturb it). Watch to see how it moves and what it eats, then walk away and know that you have done a good deed by letting it live in peace.
2. While driving on desert roads, DO keep an eye out for tortoises crossing the road. If you encounter one and have plenty of room to pass, drive slowly and carefully around it. If the tortoise is in immediate danger, pull your car over and stop in a safe place. Carefully place your fingers under and thumbs on top of the tortoise's shell, grasping it on the sides. Keep your hands away from its head. Lift the tortoise slowly and gently, keeping it level and close to the ground, as if it is in a walking position. Move it to a safe place no more than 100 yards away and in the same direction that it was traveling. Carefully set it down, preferably in the shade of a shrub.
4. If you want a pet tortoise, DON'T take one out of the desert! DO call the California Turtle and Tortoise Club: Ginger and Gary Wilfong at 510-886-2946. The Wilfongs can help you adopt a tortoise and obtain a free permit from the California Department of Fish and Game to legally keep a tortoise.
5. If you get tired of a pet tortoise, DON'T let it go in the desert! Release of pet tortoises violates the Endangered Species Act and can spread the deadly Upper Respiratory Tract Disease. Call the number listed above to find a new home for your pet.
Please drive only on designated open vehicle routes.
For information and/or brochures, contact:
Answering questions about desert tortoises: http://www.deserttortoise.org/answeringquestions/index.html
Geographical varations on environmental determinants of reproductive output of the Desert Tortoise: http://sbsc.wr.usgs.gov/products/htms/reprod.aspx
Bureau of Land Management