What is the habitat of the desert tortoise in the southwestern U.S.?
Tortoises occupy a wide variety of habitats in the United States. Two generalizations can be made. Tortoises living north and west of the Colorado River-Grand Canyon complex (California, southern Nevada, southwestern Utah, and extreme northern Arizona) generally occur in valleys, flat areas, fans, bajadas and washes. These tortoises live in the Mojave and Colorado deserts and are generally found below 4,000 feet in tree yucca (Joshua tree and Mojave yucca) communities, creosote bush and saltbush scrub habitats, and in some ocotillo-creosote habitats. They occupy a wide variety of soil types, ranging from sand dunes to rocky hillsides, and from caliche caves in washes to sandy soils and desert pavements. Tortoises must have suitable soils and terrain for constructing a burrow and must have adequate annual and perennial plants in the spring and/or summer for forage. Tortoises are usually absent from or rare in the low, very hot, and dry areas, such as the Death Valley sink. Tortoises liv
