Not everyone lives in a warm climate year round. Some tortoise owners do a wonderful job of providing a fairly natural environment for their pet tortoises in the spring, summer, and fall months but when the days get shorter and the temperatures get lower they need a winter home for their pets. This is where overwintering your tortoise comes in.
What Is Overwintering?
For tortoises that live outside during the warm months the process of bringing them indoors during the winter is call overwintering. Some tortoises naturally hibernate while others are from environments that stay warm year round therefore they need to be brought inside to prevent being frozen in the cold winter.
Overwintering simply continues to provide the same temperatures in an indoor setting as your tortoise would get in the wild, when the temperature in his outdoor enclosure would be too cold.
How Do I Know if I Need to Overwinter My Tortoise?
If your tortoise lives outdoors during most of the year and does not naturally hibernate once the outside temperature drops below 50 degrees Fahrenheit, or if he is too sick or underweight for you to allow him to go into hibernation, then you need to overwinter him indoors.
Examples of sick tortoises would include those with heavy intestinal parasite burdens, signs of respiratory infections (eye or nasal discharge), wounds, soft shells due to calcium deficiency, or if you have a new tortoise and aren't sure of his health status. These tortoises should be overwintered and not allowed to hibernate.
Some species of healthy tortoises that require overwintering indoors (unless you provide a heated, secure outdoor enclosure) if housed outdoors in the warm months include any tropical species of tortoise such as Sulcata tortoises (Geochelone sulcata), Leopard tortoises (Geochelone paradis), Indian Star tortoises (Geochelone elegans), and Red-footed tortoises (Geochelone carbonaria). These types of tortoises do not naturally hibernate in the wild, therefore they require warm temperatures year round.
Before allowing your tortoise to go into hibernation on his own, make sure that species naturally hibernates in the wild. Tortoises that do naturally hibernate include Russian tortoises (also known as the Horsfield tortoise, or Agrionemys horsfieldii or Testudo horsfieldii), spur-thighed tortoise (also known as the Greek tortoise, Testudo graeca), Hermann’s tortoise (Testudo hermanni), marginated tortoise (Testudo marginata) These are Mediterranean tortoises, which will hibernate in the colder winter weather. The desert tortoise (Gopherus agassizii) from the southwestern United States also will hibernate.
What Kind of Enclosure Should I Use?
Since overwintering typically only lasts a few months, a temporary enclosure is often provided indoors. Some people choose to construct a "turtle table" (a raised, wooden table with edges so that your tortoise can't walk off the edge) while others just use a plastic storage tote or container and leave the lid off. Larger tortoises may need entire rooms or large closets to walk around in.
The most popular choice for smaller tortoises is the storage container. They are inexpensive, compact, and easy to clean. Choose a natural substrate or bedding for the bottom of the bin and then follow the specific care instructions for housing your species of tortoise indoors. The habitat should include proper basking and daytime temperatures, a UVB light on a 12 hour cycle, adequate water dish for soaking and appropriate foods. Keep the tortoise indoors until the outdoor temperature is warm enough day and night to return the tortoise to the outdoor habitat.
Should I Just Let My Tortoise Hibernate Instead?
As I previously mentioned, letting a sick, underweight, or new tortoise whose health status you are unaware of hibernate can be dangerous. Many tortoises never wake up after hibernating because they aren't healthy enough to maintain their bodies when they "shut down" for the winter. Parasites will overtake them and infections will be allowed to run rampant if sick tortoises are allowed to hibernate.
Tortoises who don't hibernate naturally should also not be forced into a state of hibernation. Reptiles, when cold enough, will all slow down their metabolism, but it is unnatural for some. These species should be brought indoors to overwinter in a warm environment until it is safe for them to return to their outdoor enclosure (once it is consistently over 50 degrees Fahrenheit or warmer).