Gopherus agassizii
Fast Facts
- The desert tortoise is able to live where temperatures may exceed 140°F because of its ability to dig underground.
- To maximize their use of infrequent rainfall, tortoises dig catchment basins in the soil, remember where these are, and sometimes wait by them when rain appears imminent.
- Adult tortoises may survive a year or more without access to water.
Range
Southwestern United States and Northwestern Mexico
Habitat
Semi-arid grasslands, desert washes, and sandy canyons below 3,500 feet
Size
4-6 inches in height, and 9-15 inches in length
Nutrition
herbs, grasses, shrubs, and new growth of cactus and their flowers
Characteristics
The color is predominantly shades of brown, olive, yellow, and black above; yellow, brown, and black below; scutes commonly patterned with bright rays or concentric rings. Its hind legs are elephantine and its forelimbs are somewhat flattened with large, bony-core scales, short unwebbed toes’ and long claws. The head is round on a long leathery neck, and the shell is a strong, round dome.
Behavior
When forced to eat unfamiliar plants, their digestive tract needs several months to become accustomed. The desert tortoise can spend up to 95% of its life underground to escape extreme cold in winter and heat in summer. Tortoises use their front claws to dig, and this behavior makes them very difficult to find. They are active from spring to fall, and hibernate during winter.
Reproduction
They will mate anytime they are above ground. During the breeding season, males fight one another for access to receptive females. During combat, males posture, bob their heads, ram into one another, and chase one another. Often, they attempt to flip each other over by using their large gular plates as levers. If one succeeds, the loser eventually rights himself and escapes. Courtship typically consists of some head bobbing by the male, butting and biting the female to immobilize her.