How to

18 October 2016

Keeping Your Tortoise Safe During Hibernation


With your shelled companion ready to depart on a solo-adventure into dreamland, you may be wondering just how he’ll fare. Where will he retire to? Well, that responsibility falls to you, the caretaker.

A Bed Fit for a King

The box in which you place your tortoise should be doubled, one large outer box and a smaller inner one. Around the inner box place insulating material like shredded paper or packing peanuts. Double boxing ensures that when a tortoise burrows, as is natural when temperatures drop, it will not resituate in an area without proper insulation.

Hibernation Location

Tortoises can freeze to death or be frost-blinded because of improper storage or neglect. In cold places, like the UK, choosing the correct method of hibernation and keeping a consistent, cool temperature will save your tortoise’s life.

First, let’s talk about temperature. Keeping a tortoise in a warm room will increase the rate at which fat and energy reserves are used by the body, potentially depleting the entire store. Remember from our last article that tortoises have an increased appetite when they are well-lit and warm. The same applies here, even in a hibernated state. This can lead to, you guessed it, death. Similarly, exposing a tortoise to freezing temperatures will almost certainly guarantee death. So, when choosing a place to store your slumbering friend, steer clear of unheated rooms or outdoor sheds. Mediterranean tortoises should be kept at a static 5°C.

Now, we get to the method of hibernation. There are three main kinds: underground, boxed, or refrigerated.

  • Underground hibernation is a viable option depending on location. Not only is temperature a factor, soil texture and consistency also play a role. It seems a bit strange, burying your pet outside in the hopes that it survives winter. That’s a major downside to underground hibernation, the inability to monitor your pet. Additionally, the tortoise will be vulnerable to wildlife attacks and at risk if buried in overly-saturated, wet soil. However, one of the upsides is that buried tortoises are the least susceptible to freezing. To counteract the risks, burying the tortoise in an enclosed greenhouse ensures dryness and protects it from wild threats. For the most part, this method is not recommended unless your soil is sandy and climate temperate.
  • Boxed hibernation is the traditional method; however frost damage is very likely unless the tortoise is well-monitored. Location is key. Where have you stored your box o’ tortoise? If placed in an unheated area subject to temperature fluctuations you’re leaving a lot up to chance.
An example of a refrigerated hibernation setup - Img source: tortoisetrust.org
  • Refrigerated hibernation offers a temperature-controlled environment in which to store your dormant pet. It is the chosen method among reptile enthusiasts. Since it requires a bit of research to correctly utilise, cross-checking between multiple sources is highly recommended. According to the Tortoise Trust, this is the safest hibernation method when done correctly. When storing your tortoise, keep it as near to the centre as possible, adding insulating material between it and any cooling surfaces within the refrigerator. Fill in dead spaces with full water bottles. Doing so will prevent the tortoise from excessive cooling and low temperatures from refrigerant. To store, place the tortoise in a plastic container filled with soil or sand. Aside from stabilising temperature and preventing dehydration, the soil or sand will allow the tortoise to burrow. The container should have some ventilation and be secure against escape. When considering this method, make sure to check your refrigeration unit for consistency using the built-in thermostat in addition to one with a remote probe. It’s recommended to have two remote probe thermostats, one next to the hibernation box and one hanging in the air. This allows for temperature surveillance, a crucial step in keeping your tortoise safe. One of the risks associated with this method is lack of proper oxygen. Every couple days the refrigerator door should be opened to flush carbon dioxide.

Things to Keep in Mind …

Urination during hibernation is a bad sign. If this happens, a tortoise must be woken to overwinter in a warm, bright environment. Not doing so puts it at risk of dehydration.

Juvenile tortoises can only hibernate for short periods of time and are much more susceptible to temperature changes. Provide juveniles with dense soil or sand to burrow into. In fact, hibernating juveniles is a topic all of its own and should be well researched.

Rodents pose a very big risk to hibernating tortoises. Make absolutely certain that your pet is secure if stored in an outside building or attic; otherwise it is at risk of attack and life-threatening injury.

For small tortoises, the recommended hibernation period is 8 to 10 weeks. Larger specimen should hibernate for 16 weeks at the very most.


Jacqui Litvan

Jacqui Litvan, wielding a bachelor's degree in English, strives to create a world of fantasy amidst the ever-changing landscape of military life. Attempting to become a writer, she fuels herself with coffee (working as a barista) and music (spending free time as a raver).