The desert tortoise (Gopherus agassizii) is a keystone species of the Clark County Multiple Species Habitat Conservation Plan (MSHCP). The Mojave desert tortoise is listed as a threatened species, and is protected under the U.S. Endangered Species Act and Nevada Administrative Code (NAC 50.080).
It is illegal to remove a desert tortoise from the wild. Unless you have a special permit, no one is allowed to own, touch, harm harass, disturb or pick up a wild desert tortoise or disturb their burrows. If you see a desert tortoise in the wild or in an undeveloped area, do not touch them or disturb them, but please do enjoy watching them from a safe distance. For information on how you may legally adopt a captive desert tortoise, please go to our Pet Tortoise Information page, or contact the Tortoise Group at firstname.lastname@example.org.
For information about what to do if you encounter a desert tortoise on a construction site, please refer to our Developer Requirements Handout.
Desert Tortoise Facts:
Lifespan: Wild desert tortoises may live to be about 50 years old. Captive desert tortoises may live much longer however, and can survive for 80 to 100 years.
Length: Tortoises are measured with calipers. The measurement that is typically recorded is the midline carapace length, or MCL. This is the straight-line distance of the length of the tortoise’s upper shell (the carapace) at the midline of the body. Adult tortoises have an MCL of 7 to 13 inches (180 to 330 mm). Hatchling desert tortoises have an MCL of about 1.4 inches (35 mm).
Weight: Adult tortoises weigh between 8 and 15 pounds. Hatchling tortoises typically weigh around 25 to 50 grams.
The Largest Desert Tortoise: The largest desert tortoise recorded is a former pet tortoise from the Las Vegas Valley, affectionately named Monster. Monster came from a foreclosed home and was picked up by staff from the San Diego Zoo in 2011. At the time of his pick-up, Monster was over 17 inches long and weighed more than 26 pounds.
Range: The Mojave desert tortoise occurs in the Mojave and Colorado deserts north and west of the Colorado River in southwestern Utah, southern Nevada, southeastern California, and northwestern Arizona in the United States.
Habitat: Desert tortoises live in a variety of habitats from sandy flats to rocky foothills, including alluvial fans, washes and canyons where suitable soils for burrow construction might be found. It is found from near sea level to around 5,500 feet in elevation.
Diet: Desert tortoises are herbivores and will feed on a wide variety of plant species. Annual plants that germinate in the springtime are preferred foods, but desert tortoises will also eat a variety of forbs, grasses, shrubs, and cacti.
Reproduction: Desert tortoises are a slow-growing species, requiring 13 to 20 years to reach sexual maturity. They also have low reproductive rates. Females may lay between 0 and 3 clutches (or sets) of eggs in one year, depending on water and forage availability and physiological condition. Each clutch contains 1 to 14 eggs. The female lays her eggs in a small hole that she digs in a burrow or under vegetation. After she lays her eggs, she covers the nest back up with dirt to hide the eggs from predators. It typically takes about 90 to 120 days before the eggs will hatch.
Desert Tortoise Burrows: Desert tortoises may spend as much as 95 percent of their time underground in burrows. Desert tortoises use burrows for shelter against extreme temperatures, since burrows stay relatively cool in summer and relatively warm in winter. The tortoises dig their burrows in dry gravelly soil beneath creosote bushes or other large shrubs in open desert, or in the banks of washes. They may also use caves that can be found along the banks of washes or in rocky foothills. Desert tortoise burrow entrances are half-moon shaped, just like the profile of tortoise shells.
You can find more information about desert tortoises at www.mojavemax.com or the U.S. Fish and Wildlife Service's Desert Tortoise Recovery Office website.