Many owners use a fridge to hibernate pet tortoises. This artificial method provides greater reliability and control, even if the room temperature rises significantly.
However, the room temperature mustn’t fall below freezing, as the tortoise will freeze and perish. So, ensure the room used to brumate a tortoise doesn’t have wildly fluctuating temperatures.
Brumation is a form of hibernation specific to reptiles, including some species of tortoises. During this time, their heart and respiratory rates slow, which is believed to increase tortoises’ longevity.
Depending on their size, tortoises stop eating 2-4 weeks before brumation because ectotherms (cold-blooded animals) can’t digest food when they’re too cold.
Tortoises’ fat stores should be elevated, but the stomach must be empty because undigested food ferments and goes rotten, causing bacterial infection or even asphyxiation.
Tortoises enter brumation once temperatures are between 37.4 and 44.6 degrees Fahrenheit. They’ll remain asleep as temperatures fall and awaken once warmer temperatures arrive.
Brumating torts can awaken from their dormant state several times to move about or hydrate.
Do Tortoises Hibernate in The Fridge?
Temperature control is vital to the brumation process, so many veterinarians recommend using a fridge to brumate a tortoise. It’s beneficial for these reasons:
- Reaching and maintaining a stable temperature is easier.
- Monitoring and adjusting the internal temperature can be done with the existing dials.
- The low temperatures are maintained hours after a power cut.
- Protects against disturbances, such as jostling and loud noises.
However, you can’t put a tortoise in a fridge without adequate preparation.
How To Hibernate A Tortoise in The Fridge
Using a fridge to brumate a tortoise is recommended. However, it requires precautions and regular check-ins. This guide will ensure the tortoise rests safely in the artificial winter you create:
Preparation for Hibernation
Prepare the tortoise for brumation during late August. Tortoises won’t brumate until November, but they still need time to build fat reserves and digest food in their stomach.
The fasting time for a tortoise depends on its size, age, and species. However, the benchmark is 2 weeks of fasting before the tortoise’s brumation, but this can be up to 4 weeks for larger species.
Consult a vet beforehand, as the tortoise may need to delay its brumation to gain more weight. Allowing a tortoise to brumate without sufficient fat reserves will likely lead to starvation.
After its last meal, a tortoise should be kept at lowered temperatures.
Its habitat should be kept at 55.4 degrees Fahrenheit to ensure the food in its stomach can be fully digested. It’ll also mimic the drop in temperature of the wild.
This period will depend on how long the tortoise takes to digest its food. Depending on their size and species, some tortoises take less or more time than others.
Other than temperature, you’ll also need to change the amount of daylight. This doesn’t need to be exact, but tortoises enter brumation when the days grow shorter.
So, gradually lower the amount of light until it’s time to brumate.
While digesting, give the tortoise a chance to bathe each day. A tortoise going into brumation can have a full bladder, but its bowels should be empty.
Also, bathing ensures the tortoise remains well-hydrated before brumating. To do this, bathe the tortoise in a shallow bowl of lukewarm water.
Choosing The Fridge
Avoid placing a brumating tortoise in the same fridge you keep food, as doing so puts your family at risk of contamination from Salmonella.
Also, used fridges will fluctuate in temperature as you open and close the door, which puts the tortoise in danger of coming out of brumation early.
A new fridge will maintain the right temperature, and its internal thermometer will be more reliable.
Alternatively, put the tortoise in a box and keep it away from your food.
Fill And Test The Fridge
A full fridge will maintain a more stable temperature, so fill it with 2-liter bottles of water. Test the stability of the temperature inside the fridge with a reliable thermometer to monitor it when it’s empty and full.
Don’t use a fridge with more than a 2 degrees Celsius difference from the actual temperature. Alternatively, adjust the fridge thermostat to account for the differential.
The tortoise will need a box, whether it’s in an existing or new fridge. Good options include cardboard or wooden boxes, but choose plastic for species that require more moisture.
Ensure it’s big enough for a tortoise to turn around. The lid should be tight and secure, and the sides should be tall enough to prevent escape.
Punch plenty of holes into the lid. Then, fill the box with a substrate, ideally sterilized soil.
Brumation doesn’t just involve putting your tortoise in the fridge. Monitor your tortoise to ensure it remains safe and healthy.
Fridge Temperature for Tortoises
A tortoise should be kept in temperatures of 41 degrees Fahrenheit or 5 degrees Celsius. This temperature can fluctuate to anywhere between 37.4 – 44.6 degrees Fahrenheit.
Never allow the temperature to dip below 37.4 degrees Fahrenheit, as this will be too cold.
Allow Oxygen Inside The Fridge
A brumating tortoise still needs to breathe but requires less air than normal. Wild tortoises bury themselves deep in the ground, where oxygen levels are low.
There are two ways to give oxygen to a tortoise. You can open the fridge’s door, which should be done at least 3 times a week, for about 1-2 minutes.
Alternatively, you can install an aquarium air pump. For an average-sized fridge, use a pump that can move 200 liters of air per hour.
Never leave a brumating tortoise unattended for long periods, even with an air pump. A power outage can lead to a lack of oxygen inside the tortoise’s fridge.
Check The Tortoise’s Health
Handle the tortoise to check its weight at least once a month during brumation. Tortoises lose about 1% of their mass per month of brumation.
For this reason, tortoises rarely brumate for more than 12 weeks. If the tortoise loses over 1% of its body weight, bring it out of brumation.
Check if the tortoise has urinated. If it has, this means that it’s dehydrated. In this situation, wake it up but don’t put it back into brumation.
How Long Do I Brumate A Tortoise?
The length of the brumation depends on the tortoise species.
For example, the Jackson Ratio is used for spur-thighed and Hermann’s tortoises, while the McIntyre Ratio is used for horsefield tortoises.
Small tortoises brumate for 8-10 weeks, while large tortoises do so for up to 16 weeks.
Waking The Tortoise
When the tortoise has finished brumating, remove it from the fridge and place it near a heat source. A basking lamp or UV lamp is ideal.
This area should be isolated and free from loud noises and foot traffic. Now, allow the tortoise to slowly wake itself up, which will take 2-3 hours.
Once the tortoise begins stirring, provide it with water. If it seems awake enough, bathe it in a shallow pool of lukewarm water (less than neck height).
Afterward, you can place it back in its enclosure, gradually increasing the temperature to its normal range.
The tortoise should start eating food over the next 10-14 days.
Do I Need To Hibernate My Tortoise?
Not all species of tortoise brumate, such as leopard and Indian star tortoises.
So, determine what species the tortoise is and research whether it requires brumation during the winter. Brumating species of tortoises include the following:
- Hermann’s tortoise
- Horsefield tortoise
- Russian Tortoise
- Marginated Tortoise
- Gopher Tortoises
- Mediterranean tortoises
Sometimes you shouldn’t brumate a tortoise, even if it’s a brumating species. If a tortoise is ill or underweight, it is best to forgo brumation. Also, juvenile tortoises don’t need to brumate.