Preparation for hibernation begins as the days become shorter and cooler. Tortoises begin to decrease their food intake and become increasingly sluggish. Hibernation can begin as early as mid-September or as late as mid-December. It ends as early as mid-February or, more commonly, anywhere from March to late April. If natural burrows are provided, be certain that they remain dry. Captive tortoises often dig unsatisfactory burrows that do not adequately protect them from flooding. Unused dog houses or equipment sheds containing dry bedding (straw, blankets, towels) are usually adequate. A doggy door can be installed on the structures to allow tortoises that awaken during unseasonably warm weather to go outside and wander about.
Tortoises can be allowed to hibernate in a garage by placing them in dry boxes containing absorbent bedding. They should be checked periodically, and the bedding should be changed periodically as needed. It is not uncommon for rats to prey on hibernating tortoises. Flies frequently attack tortoises at this especially vulnerable time, too. Therefore, careful and thorough examination of them is very important.
Tortoises exhibiting obvious signs of illness or injury or those with suspected illness should not be allowed to hibernate. As hibernation ensues, the body temperature of tortoises decreases, and their immune systems become less capable of protecting them against disease. As a general rule, captive hatchlings should not be allowed to hibernate for their first 3-4 years of life. Hibernation is not necessary for captive tortoises each year.
Hibernation is an adaptation of wild animals that allows them to avoid adverse climatic conditions. Captive tortoises that are kept warm all winter usually do not hibernate completely. They usually become lethargic and refuse to eat on their own. These tortoises can and should be gently force-fed once or twice weekly. They can be given water by syringe.