Tortoises are one of the most popular kinds of reptiles kept as pets. Although tortoises are portrayed as being easy to keep, many suffer from ill health and ultimately die because their owners are ignorant of the correct husbandry requirements of tortoises.
One of the biggest stumbling blocks is winter hibernation. Some (not all) species of tortoise hibernate for several months during the year. Pet owners that incorrectly prepare their tortoises for hibernation risk their tortoises dying during, or just after hibernation.
Which species of pet tortoises need to hibernate?
Not all species of tortoises hibernate. Tortoises from temperate climates will hibernate for several months out of the year (3 months on average), whereas tropical tortoises do not need to hibernate. The following species of tortoises commonly kept as pets should be hibernated:
• Spur-thighed or Greek Tortoise (Testudo graeca)
• Hermann’s Tortoise (Testudo hermanni)
• Marginated Tortoise (Testudo marginata)
• Horsfield’s or Russian Tortoise (Testudo horsfieldi)
• North American Box Turtles: Carolina or Eastern box turtle (Terrapene carolina carolina), Three-toed box turtle (T. c. triunguis), Ornate box turtle (T. ornata), and the Florida box turtle (T. c. bauri).
• Hinge-back Tortoises: Bell’s hinged tortoise (Kinixys belliana), Eroded hinged tortoise (K. erosa), Natal hinged tortoise (K. natalensis), Home’s hinged tortoise (K. homeana).
• Padlopers: Greater padloper (Homopus femoralis), Parrot-beaked tortoise (H. aureolatus), Karoo tortoise (H. boulengeri), Speckled padloper (H. signatus), Nama or Berger’s tortoise (H. bergeri).
Which species of pet tortoises should not be hibernated?
Never hibernate a tortoise if you suspect it may be a tropical variety. If you are unsure about the species you own, consult a veterinarian or tortoise specialist. The following tropical tortoises SHOULD NOT be hibernated:
• African spurred tortoise (Geochelone sulcata)
• African leopard tortoise (G. pardalis)
• Red Footed Tortoise (G. carbonaria)
• Yellow Foot Tortoise (G. denticulata)
• Burmese Brown Tortoise (Manouria emys)
How do I decide whether my tortoise is fit to hibernate?
Even if your tortoise belongs to a species that commonly hibernates, if it is sick or underweight you should NEVER attempt to hibernate it. Forcing an ill tortoise to hibernate can be a death sentence. Thus, you should decide at least 2 months before the onset of winter (not the week before!) whether your tortoise is healthy enough for hibernation.
Tortoises need adequate reserves of body fat to live off of through winter – if these reserves run out too early, the tortoise’s body will start using up the fat in muscles and internal organs, and eventually die. If your tortoise does not have adequate fat reserves at least a couple of months before hibernation, it will not have them by the time of hibernation.
Pet owners should go through a pre-hibernation health check to ensure that their tortoise is fit for hibernation: examine the eyes for swelling or discharge, the nose for discharge, the cloaca for signs of infection, the legs for any unusual swellings or bumps (e.g. abscesses), the ears for signs of abscesses, and the inside of the mouth for signs of mouth-rot. If you do not feel confident performing this exam yourself, consult a veterinarian with experience dealing with reptiles.
How should I feed my tortoise before it starts hibernating?
As autumn approaches and temperatures decrease, tortoises will gradually reduce their food intake (thus, if they are underweight at the end of summer, they will not gain any more weight before winter). By the time a tortoise enters hibernation, its gastrointestinal tract should be free of any undigested food material.
A tortoise that has been fed in the last month to 6 weeks should not be hibernated, or should have hibernation delayed. It is quite common for owners to kill their tortoises by giving them “one last meal” before they begin hibernation. Note that although tortoises should be denied food, owners should still bathe their tortoises and encourage them to drink.
What kind of quarters does a hibernating tortoise require?
Failure to provide adequate protection during hibernation is one of the biggest killers of captive tortoises. There are a number of methods of hibernating your tortoise – if you have used a particular method successfully, stick with the one you are familiar with. If you have never hibernated a tortoise before, then this procedure is suggested:
1. The following materials are needed: one larger box and one small box made of either wood or heavy-duty cardboard, insulating material such as wood shavings/chips, Styrofoam chips, shredded paper, etc., and a thermometer (maximum-minimum reading thermometers are recommended).
2. The tortoise should be placed in the smaller box with a couple inches of insulating material. This should be a fairly tight fit, allowing little movement.
3. Line the larger box with a thick layer of insulating material and place the smaller box within the large box.
4. Do not puncture the hibernating box with holes. Covering the top with newspaper and a sack should allow enough to air to filter through.
5. Use a thermometer to record the temperature of the hibernating box. Some people will actually tape the end of the thermometer probe to the tortoise’s shell.
6. The ideal temperature for hibernation is 5oC/40o F. However, a range of 0-10oC (32-50oF) is acceptable. Extremely cold temperatures can cause your tortoise to freeze to death, and excessively warm temperatures can cause your tortoise to prematurely exhaust its fat reserves or begin to wake up. If the temperature reaches unsuitable levels, move the hibernation box to a more appropriate location.
7. Tortoises should be regularly checked and weighed to ensure that they are not losing weight too rapidly – handling your tortoise while it is hibernating will not disturb it.
8. If your tortoise awakens during winter, or shows signs of urination, it should be allowed to come out of hibernation.
9. Three months is the average time for hibernation. Hibernation should not be allowed to continue until spring.
10. Box turtles usually require a more humid environment to hibernate in, and the period of hibernation may be shorter.
How do I wake my tortoise from hibernation?
As the ambient temperature increases, your tortoise’s metabolism will begin to speed up. Listen carefully for sounds of movement from the hibernation box – when you hear sounds that indicate your tortoise is emerging from hibernation, place the hibernation box near a heater, allowing it to gradually warm up. After a few hours, remove the tortoise and place it in a warm and bright environment. Examine the tortoise for any health problems (similar to the pre-hibernation check).
It is essential to get the tortoise to drink as soon as possible. This can be accomplished by resting the tortoise in a sink, bathtub, or container filled with an inch of tepid water. If the tortoise does not drink and flush out the accumulated waste material, it will feel disinclined to eat. Post-hibernation anorexia is a common condition of captive tortoises. If your tortoise is not eating within the first week of emerging from hibernation, it should be seen by a veterinarian.
There are a lot of factors involved in safely hibernating a pet tortoise. If you are unsure about your tortoise’s fitness to be hibernated, or the correct way to hibernate your tortoise, always consult a veterinarian.
(photo: herwings).