Desert Tortoise Gopherus agassizii Within the desert's fragile ecosystem, tortoise populations are rapidly diminishing; in some places they have disappeared. Losses are due to vandalism, to raven predation, disease, collections for pets (now illegal), and habitat degradation. Habitat has been lost or damaged from mining, livestock grazing, development of desert lands for agriculture, sub-divisions, high-ways, industrial uses and off-road vehicle use. Tortoise populations grow slowly because of their low reproductive potential. Females do not breed until 15 to 20 years old and then may lay clutches of eggs only when adequate forage is available. Also, survival of juveniles is low, only 2-3 per 100 hatched may live to become adults. To read more about the desert tortoise in the wild click on the article titles listed below. You may also like to browse through the Special Reports and Occasional Papers on the DTPC Research Papers page and take the DTNA Virtual Field Trip. Useful links to off-site desert tortoise information can be found in the box on the lower right. Other Tortoise Resources Desert Tortoise Council Captive Desert Tortoises California Turtle & Tortoise Club Las Vegas Tortoise Group Reno Tur-Toise Club State Offices Arizona Game & Fish Dept. California Dept. Fish & Game Nevada Div. Wildlife Utah Div. Wildlife Resources Federal Offices Bureau of Land Management BLM-Arizona BLM-California BLM-Nevada BLM-Utah US Fish & Wildlife Service Commonly Asked Questions About the Desert Tortoise and Answers by Kristin H. Berry Habitat Use and Food Preferences of the Desert Tortoise, Gopherus agassizii, in the Western Mojave Desert and Impacts of Off-road Vehicles by W. Bryan Jennings Life Cycle of the Desert Tortoise brief, illustrated guide to the life history of desert tortoises. Plants Eaten by Juvenile Desert Tortoises in the Central Mojave Desert by E. Karen Spangenberg The Desert Tortoise and Upper Respiratory Tract Disease by Elliot Jacobson