Important: No one care sheet can possibly cover all the variables in different localities that influence the care of our desert tortoises, as well as the ongoing discovery of new information. It is highly recommended that you join an online discussion group where fellow keepers can assist with questions/issues not covered in the following care sheet.
This care-sheet provides information on caring for adult desert tortoises and their hatchlings. Your location and environment may require modifications of suggestions. The desert tortoise (Gopherus agassizii) is endangered in the wild and is protected under Federal and State laws. It is illegal to buy or sell desert tortoises, or to take them from the desert. In California, a permit (http://tortoise.org/general/permit-rev.html) is required to possess captive desert tortoises.
Male desert tortoise. Photo by Francisco Velasquez
Obtaining a permit is simple. Contact the California Department of Fish and Wildlife, or the California Turtle and Tortoise Club for a permit application. The California Department of Fish and Game provides a tag to attach to the tortoise, and this is a useful way of identifying your tortoise if it should stray. Possession of a permit/tag does not authorize breeding. California Turtle and Tortoise Club Adoption Chairs now tag all tortoises that are placed through the CTTC adoption programs.
For good reason, it is against the law to release captive desert tortoises back into the wild. Released captives have a low survival rate and may pass diseases into the wild population with devastating consequences. Contact the California Turtle and Tortoise Club if you need to find a new home for a tortoise. Most chapters of CTTC have numerous desert tortoises needing new homes, so please do not take them from the desert.
Care of Adult Desert Tortoises
Desert tortoises are known to live as long as 60-80 years, and may live even longer. Because growth varies with food availability and other conditions, tortoises grow faster in captivity than in the wild. It is impossible to determine the exact age of an adult tortoise.
In order to thrive, adult desert tortoises must be kept outdoors in a large area. They should be provided with shelter from the sun and cold, and a place to retire at night. They need plenty of room to exercise and browse. If possible, give them the run of your entire yard. Make sure that the yard is escape-proof and that pools are fenced off. Eliminate any poisonous plants (http://www.tortoise.org/general/poisonp.html) , and do not use chemical pesticides or fertilizers in the area. Toxicity scale for poisonous plant list is at bottom of the list. Note that the list is geared towards mammals as there no accepted list for tortoises thus many keepers prefer to err on the side of caution and provide plants for them that we KNOW are SAFE. It is cruel and inhumane to tether a tortoise by the legs or by holes drilled in the shell. Consult with CTTC on proper enclosures, fencing and security instead.
Healthy tortoises have enormous appetites! Growing native grasses, wildflowers, grass, weeds, dandelions, alfalfa (in moderation), nopales (Opuntia cactus), mulberry tree leaves, grape leaves, common cheese mallow and other mallows, chickweed, nut grass, and (for treats) rose petals, nasturtium and hibiscus flowers are excellent food sources.
Desert tortoise dining on dandelions.
Photo by Michael J. Connor
If limited in growing foods, supplement this diet with occasional foods such as endive, escarole, squash such as zucchini, chopped carrots, small amounts of kale, romaine and other dark-green leafy vegetables. Sprinkling the food with ground-up rabbit or guinea pig pellets or mixing with Bermuda or Orchard grass hay is a good way to add extra fiber to the diet. See "Feeding" in the "Care of Hatchling Desert Tortoises" section for sources from which to purchase Desert Tortoise Seed mixes and edible native wildflower seeds.
Tortoises have a high calcium requirement: occasionally sprinkle the food with calcium carbonate (WITHOUT phosphorus as this binds calcium making it unavailable for bone/shell growth), or offer an always available calcium-rich source such as boiled chicken eggshells or cuttlefish bone (preferred - always remove hard, thin outer layer to prevent choking) for them to eat. DO NOT use calcium with added vitamin D3 if tortoise is kept outdoors. Occasionally sprinkle the food with a suitable vitamin preparation if you are unable to provide a large variety of natural foods to graze upon. All foods should be fertilizer free and MUST be pesticide free. Provide a shallow dish of water for drinking and soaking - KEEP CLEAN daily and ALWAYS IN SHADE.
Avoid excessive use of foods that are high in oxalic acid (which binds calcium) such as parsley, purslane, amaranth, spinach, beet leaves, collards, Brussels sprouts. Also avoid excessive foods in the Brassica family such as broccoli, cauliflower and mustard greens as they suppress iodine uptake and may be implicated in health issues, i.e., goiter. Excessive fruits (other than the "cactus apple" from Opuntia cactus in season) should not be fed as they may upset digestive flora and can result in overgrowth of intestinal parasites. NO banana at all, especially to hatchlings as they can choke. DO NOT feed soy, tofu nor ANY animal protein such as cat or dog food. Commercial pellet tortoise food products from pet stores are not a good choice for the major part of a desert tortoise diet.
Desert tortoise hatchlings have a flat plastron (bottom shell) until they reach about 8 inches in length (10-15 years of age in the wild; 5-10 years in captivity). At this time the plastron of the male becomes noticeably concave, whereas the female’s plastron remains flat. Adult males also have longer gular horns, a longer tail, and enlarged glands under the chin.
Shortly after emerging from hibernation, male tortoises will begin pursuing the females. Male tortoises will frequently fight with each other at this time. Because of the risk of one being overturned, it may be necessary to keep males separated from each other. Sometime between May and July females will begin to carefully search for a suitable site to dig their nests, in which they will lay a clutch of 2 to 12 pingpong-ball sized eggs. Often they will undertake several "trial" excavations in the process. Occasionally a female may lay more than one clutch in a season. PLEASE NOTE that it is against Federal and California State regulations to intentionally breed desert tortoises. You may NOT artificially incubate eggs. If laid in the ground and they hatch, please contact your local CTTC Chapter for placement assistance. Please do not immediately feed grocery produce to newborn hatchlings as they lack digestive flora to digest such foods (digestive flora is established by eating small amounts of dirt around the base of plants or by eating dried fecal matter ("scat") from other healthy tortoises of the same species.
It is important that the keeper gets to know the normal behavior of his/her tortoise because behavioral changes are often the first sign of illness. Tortoises are susceptible to respiratory ailments, such as the Upper Respiratory Tract Disease (http://www.tortoise.org/general/urds.html) that has decimated the wild population in California and Nevada. Warning signs are a runny or bubbly nose, loss of appetite, and gasping. Respiratory disease symptoms can often be cleared if treatment is begun immediately, however, there is no "cure" for URTD. For swollen eyes, wounds or injuries contact a veterinarian immediately. Swollen and sunken eyes are often mis-diagnosed as vitamin A deficiency when it is in fact a dehydration or respiratory illness issue. NEVER allow a veterinarian to inject vitamin A if a tortoise is grazing on grasses/weeds and eating a healthy green diet. Sick or wounded tortoises MUST be moved inside away from flies. Worms and other parasites are sometimes a problem in desert tortoises. Symptoms such as loss of weight, and lack of energy for no apparent reason are an indication can be indicative of parasite overload and a fecal exam should be done by a qualified tortoise veterinarian. DO NOT allow a vet to give your tortoise Albendazole or Ivermectin as they can cause more serious health issues or even death.
The California Turtle & Tortoise Club maintains a list of Veterinarians_Who_Treat_Tortoises. (http://www.tortoise.org/general/vetlist.html) Also check Yahoo_ Groups_Vets_for_Herps/ (http://groups.yahoo.com/group/vets_for_herps/) for veterinarians recommended by keepers and Tortoise_Trust_HerpVets. (http://www.tortoisetrust.org/articles/herpvets.htm)
ASK about the veterinarian's experience treating tortoises before allowing the treatment of your tortoise.
Usually by late October as the days become cooler, the tortoise will eat less, bask less, and appear sluggish. A suitable hibernation place may have to be provided. Some tortoise owners use a dog house insulated with a thick layer of dry soil, leaves, or shredded newspaper. The entrance should be covered with a tarp to protect it from flood or rain.
Many keepers prefer to "store" their pets in the garage. The tortoise is placed in a stout cardboard box, that is deep enough that it cannot climb out, and is covered with insulating layers of newspaper. The box is placed up off the cement floor in an area free from drafts or rats. If the box is placed in your garage, remember not to run automobile engines because of the risk of poisoning from the fumes. A cool closet is also a safe place for hibernation. Many keepers now prefer a "box-in-box" method, where the inner box is large enough for the tortoise to turn around in which is placed in a larger box 3-5 inches larger with insulating layers of newspapers below and around the inner box. This insulation layer helps maintain more stable temps and is very helpful is utilizing a garage or area that is subject to temperature swings. Utilize a minimum/maximum thermometer and strive to maintain temps at 42 to 55°F; do not keep in an area where temps will stay at 60 to 65°F and above for extended periods of time as it can cause increased metabolism, resulting in excessive water/weight loss and possible illness, even death. Use a minimum/maximum thermometer "weather station/remote sensor" to monitor temps inside AND outside of the box to monitor temps in your chosen location, striving for stability.
Some tortoises will build a burrow, and in some areas may successfully hibernate themselves. However, before allowing this, consider the location of the burrow. If there is a significant risk of flooding or the tortoise getting wet - and cold - from heavy rainfall do not allow your pet to hibernate there. A wet and cold tortoise may become ill with respiratory illness and/or pneumonia and can die during "hibernation".
A hibernating tortoise should be checked periodically. A sleeping tortoise will usually respond if its foot is touched. If the tortoise should waken during a mid-winter warm spell, water may be offered, BUT DO NOT FEED. As weather cools again, encourage it to return to sleep. When the days begin to warm, around March or April, the tortoise will become active in its storage box. At this time, a warm bath should be given, and the tortoise will often take a long steady drink. Within a week or two it should resume its normal activity of eating, exercising and sunbathing.
It is important that a tortoise be plump and in good health before hibernating, otherwise, it may not survive the winter. By the end of the summer, a well fed tortoise will form fat reserves around its shoulders and legs. Weigh adult tortoises before and after "hibernation"; juveniles and hatchlings should be weighed before and then every two weeks and if more than 1 to 2 percent of body weight is lost, consider moving to a cooler location. If dehydrated, awaken, hydrate and keep up per below instructions for remainder of winter.
DO NOT HIBERNATE A SICK OR INJURED TORTOISE! Nor one that has been treated that summer for respiratory infection such as URTD/RNS/URDS!
If for some reason you do not wish your tortoise to hibernate, it must be brought indoors and kept at a warm temperature (75 to 85°F) for it to remain active, simulating daylight hours of 13-14 hours a day. It will require room for exercising and regular feedings and on sunny warm days at 65 to 70°F, should be taken outside into a wind-sheltered, sunny area for a couple of hours as often as possible.