Despite its name, the reptile is not well adapted to desert conditions. It evolved tens of thousands of years ago, scientists say, when the landscape was dominated by lakes edged with Joshua trees and junipers. Scientists believe that large numbers of female desert tortoise carcasses discovered near Joshua Tree National Park may have been trying to ward off extinction due to prolonged drought with a potentially lethal response: exhausting their water and energy to lay eggs.
Drought conditions also kill off nutritious foliage and trigger a crash in populations of rodents that eat them. As a result, dogs and coyotes, which normally thrive on kangaroo rats and rabbits, turn to the lumbering tortoises for sustenance, according to surveys by state and federal biologists.
He covers issues ranging from religion, culture and the environment to crime, politics and water. He was on the team of L. Times writers that earned the Pulitzer Prize in public service for a series on Latinos in Southern California and the team that was a finalist in for the Pulitzer Prize in breaking news. How a marine inversion over the L. Livestock grazing and urban development, along with the ever-increasing use of off-road vehicles, continue to degrade the tortoise's vanishing habitat, while Army translocation projects threaten to devastate the Mojave population.
The last administration failed to protect many species on the brink of extinction. Help save them now. It's important to note that desert tortoises in California and the Southwest are two separate species. In a study, scientists declared that tortoises living north and west of the Colorado River — the Mojave population now called Agassiz's desert tortoises, or Gopherus agassizii — are officially a different species from tortoises in Arizona and Mexico, previously called "the Sonoran population of desert tortoises" and newly dubbed Morafka's desert tortoises, or Gopherus morafkai.
That study showed each desert tortoise species to be even rarer than previously thought. For information on captive desert tortoise care, the tortoise adoption program, or tortoises found in urban areas, please contact TAP azgfd.
For information on desert tortoises in the wild, please contact turtlesproject azgfd. E-news Signup. My Account. Search for:. Wildlife Desert Tortoises. Nongame Species. Desert Tortoises Arizona has two native species of tortoise, the Sonoran desert tortoise, Gopherus morafkai; and the Mojave desert tortoise, Gopherus agassizii. Photo by George Andrejko. Resources for the public Desert tortoise adoption Captive desert tortoise care Resources for Environmental Consultants Desert tortoise handling guidelines Desert tortoise survey guidelines Mitigation measures Natural History The desert tortoise is an herbivorous and completely terrestrial turtle with a brown, high-domed shell and stout, elephantine legs.
A desert tortoise emerges from its burrow Adaption to desert life Another adaption that makes the desert tortoise suited for desert life is the ability to acquire almost all of its water from the plants that it eats. Reproduction Adult desert tortoises are generally solitary animals and individuals of the same sex may engage in combat when they cross paths in the wild.
The male desert tortoise on the left was flipped over during a battle with the other male. This type of defeat can determine territorial and mating disputes. Hatchling desert tortoise Distribution The Mojave desert tortoise inhabits the area north and west of the Colorado River and is listed as threatened under the Endangered Species Act.
Per Commission Order possession limit is one desert tortoise per person per household. Desert tortoise poster [pdf] For information on captive desert tortoise care, the tortoise adoption program, or tortoises found in urban areas, please contact TAP azgfd.
Education Hunter education Boater education Teachers Other education classes. Memberships Conservation Membership. During periods of sufficient rainfall tortoises drink from temporary rain pools. A common defensive behavior when molested or handled is to empty the bladder, leaving the tortoise at a considerable disadvantage during dry periods.
For this reason, desert tortoises should not be handled when encountered in the wild. Reproduction begins between ages , with clutch sizes of eggs.
In years with low rainfall, females may lay few to no eggs. Females can store sperm for five years or longer, meaning they can reproduce for several years after mating.
Nests are built and eggs are laid in late spring or early summer. The hatchlings appear in 90 to days. The mother leaves the nest, so once the hatchlings appear, they must survive on their own. Tortoises depend on bushes for shade and protection from predators such as ravens and coyotes. To escape the temperatures of cold winters and very hot summers, many tortoises live in burrows.
The spring and summer burrows vary from 18 inches to five feet long, but may only be a few inches from the surface. Winter burrows tend to be about eight feet long and may be two to three feet from the surface. They often share burrows and may use multiple burrows scattered across the landscape. They hibernate for up to nine months each year, becoming most active from March to June and September to October. When they are young they seldom venture more than feet from their burrow.
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