desert tortoise information & collaboration

What is a desert tortoise?

Desert tortoises are large, herbivorous (plant-eating) reptiles that occur in the Mojave and Sonoran deserts in southern California, southern Nevada, Arizona, and the southwestern tip of Utah in the U.S., as well as Sonora and northern Sinaloa in Mexico. The Mojave Desert Tortoise (Gopherus agassizii) occurs north and west of the Colorado River, and the Sonoran desert tortoise (Gopherus morafkai) occurs south and east of the Colorado River.

Desert tortoises are well adapted to living in a highly variable and often harsh desert environment. They spend much of their lives in burrows, even during their seasons of activity. In late winter or early spring, they emerge from over-wintering burrows and typically remain active through fall. Activity decreases in summer, but tortoises often emerge after summer rain storms, which are more common in the southern part of their range. Mating occurs during spring, summer, and fall.

During activity periods, desert tortoises eat a wide variety of herbaceous vegetation, particularly grasses and the flowers of annual plants. During periods of inactivity, they reduce their metabolism and water loss and consume very little food. Adult desert tortoises lose water at such a slow rate that they can survive for more than a year without access to free water of any kind and can apparently tolerate large imbalances in their water and energy budgets.