Health Care for the Desert Tortoise

General Information

The desert tortoise is a dry land turtle. It has thick skin, the legs are scaled and the feet are “elephant-like” or webbed. Unlike other turtles the desert tortoise does not swim. Its upper shell, the carapace and the lower shell, the plastron are light to medium brown and are fused, not hinged like box turtles. As the tortoise grows the new scales develop beneath the old ones and the old ones wear down. An average adult tortoise may measure 5-6 lbs; however there is considerable variation in size.

Diet

The desert tortoise is an herbivore, feeding on native grasses and leafy plants mainly. In captivity they do well on a diet of grass or grass cuttings and other cactus flowers, garden plats, flowers and shrubs. Iceberg lettuce is not nutritionally adequate to feed to any animal, especially tortoises. On a weekly basis a mixture of green leafy lettuces, such as collard, kale, mustard, turnip and mixed vegetables such as carrots/peas/corn/beans etc with small amounts of fruits such as strawberries and melons can be given to supplement the grass diet. Food should be served on a clean dish or a feeding surface within the tortoise’s reach to prevent ingesting gravel or sand that can potentially irritate or block the intestines. A shallow dish should be available for water at least weekly.

Habitat

In Arizona tortoises can and should be kept outdoors during the summer months. The best environment is an area that has natural grass for grazing and shaded areas for protection during the heat of the day. The area needs to be escape proof with fencing. The best material to fence in a tortoise is cement block walls. If chicken wire or lattice like fencing is used the tortoise will try to climb and very easily fall over on its back which can be potentially fatal. Tortoises can sometimes right themselves but not always. A tortoise on its back in the heat of an Arizona sun is very often fatal. The area should have adequate grass for eating, an area for sunning and a shaded area to prevent overheating. Tortoises like to dig shallow dens to avoid the heat of the day or a sheltered area can be provided for the same purpose.

In the fall when the night temperatures routinely drop into the 50s the desert tortoise will prepare to hibernate. It will slow its eating until it will finally stop approximately 6 weeks prior to true hibernation. It will become more lethargic and not move around during the daylight hours. It is then time to prepare a place for hibernation. The temperature in the area that the tortoise is to hibernate in should be in the 50s or 60s during the day and not cooler than low 50s and upper 40s during the night. A desert tortoise can freeze to death when temperatures drop below 40 degrees. The ground water level in the Phoenix area is higher than is recommended for hibernation of the tortoise, due to irrigation and constant watering of the lawns. For that reason hibernating your tortoise in an outdoor shed area is preferred. Areas that can protect from the cold but keep the tortoise cool enough to truly hibernate. If the temperature is to warm a tortoise can go into estivation which is not a true hibernation and use too much of its body resources without eating. Placing the tortoise in a box with padding such as several towels to allow burrowing is recommended. That way you can check on your tortoise without disturbing it. During the winter season you can get your tortoise out of the hibernation area and offer it water to drink periodically. Once monthly is adequate. Tortoises absorb water from their bladder so if they urinate when disturbed they should be allowed to drink water to replenish their supply.

When the tortoise comes out of hibernation, usually in March or early April in Phoenix it should be allowed to soak for a least ˝ hour to allow time to warm up and drink, it may take several days for the tortoise to fully warm up enough to start eating. Any sign of upper respiratory disease, discharge from the nose or eyes, sneezing or wheezing, should be cause for a trip to a veterinarian.

A tortoise in captivity should never be returned to the wild. Recent studies have indicated that all those tortoises released die quickly. They do not adapt well to the vegetation in the wild and will compete with any tortoises in the release area. They also can carry diseases to the wild population that can be devastating.

Determining the sex of a tortoise can be done once the tortoise reaches sexual maturity, usually at 8-10 years of age. A female has a flat plastron (lower shell) and the male has a concave plastron. The tail of a male is longer than a female and nucal scale, under the chin of the male is much more pronounced. A female tortoise can lay eggs for up to 4 years from one mating. The eggs are laid in a shallow hole dug by the female in the spring or summer months, then buried and left on their own. The eggs will hatch in the fall and the babies will dig out of the h ole on their own. A newly hatched tortoise will usually have an egg yolk, sac attached that is providing food for the first several days of life. Do not remove the sac from the baby.

A desert tortoise is very vulnerable in the first several years of life to all kinds of predators, especially birds. In the first year it is recommended that the baby tortoise be kept in an aquarium with a heat lamp keeping daily temperatures between 85 and 95 degrees and a ultraviolet light to simulate sunlight. Sunlight filtered through glass does not allow the needed ultraviolet rays from helping maintain the vitamin D levels in the young tortoise. Nighttime temperatures should drop into the 70s. The best substrate to keep in an aquarium is towels or artificial turf that is easily cleaned and won’t provide material that can clog the intestinal tract of a baby tortoise. Baby tortoises do need a source of bacteria to help the gut digest food so can be offered some clean dirt or even healthy stool from an adult tortoise. Feeding a young tortoise requires that vegetables, greens such as romaine lettuce or collard and some fruits like melon or strawberries be cut into smaller sizes to allow the baby to swallow well.

Adult tortoises need a high fiber diet made up mainly of grasses, even babies should be exposed to an outside environment to allow them to become accustomed to eating grass as well as exposure to sunlight. Be very careful to have an escape proof area for the tortoise to be in. Keep all tortoises, regardless of size safe from large dogs that tend to see them as chew toys and can do significant damage even to adult tortoises.

Desert tortoises do not swim! Please prevent them from falling into swimming pools. Make sure there is adequate shade during the hot summer days. Tortoises can only regulate their body temperatures by adjusting their surrounding environment. They can die from excessive heat if not protected. The healthiest environment for a desert tortoise is a confined grassy area with plenty of sunshine and areas of shade at all hours of the day, a place to get clean water and protection from predators.

This health care information for desert tortoises was compiled by Marilyn Lieb, D.V.M., from material gathered at the Arizona-Sonora Desert Museum in Tucson, Arizona, and permission to quote or reproduce details from it is granted when due acknowledgement is made.