Minster Veterinary Surgery's logo

Call us now: 01460 52487

24/7 services to cater for all pet emergencies

A rabbit on the lawn

Advice & information

Call us to book an appointment

01460 52487

Under construction.

Hibernation in captivity is only suitable for healthy Mediterranean Tortoises and Horsfield tortoises. Leopard tortoises (Geochelone/Stigmochelys pardalis), African spurred (Sulcatas) (Geochelone sulcata), Egyptian tortoises (Testudo kleinmanni), Aldabran (Dipsochelys elephantine), Red-foot (Geochelone carbonaria), Yellow-foot tortoises (Geochelone denticulate) and most turtles MUST NOT be hibernated.

 

In the wild hibernation is an adaptation to survive cold winters within a tortoise’s natural range. They have a long period of WARM weather to prepare for SHORT hibernation in the Mediterranean winter, where they are no longer able to control their body temperature. Mediterranean tortoises hibernate for shorter periods in the wild between 10-12 weeks. In contrast to this, in captivity they are exposed to a SHORT period of warm weather to prepare for a LONG period of dormancy, inactivity and hibernation. In the UK, it is common for the tortoise to hibernate for 5-6 months (from October to April). This is deemed too long and the recommended maximum duration of hibernation in most of the Mediterranean species is 3 months. Ideally all healthy Mediterranean species require some form of winter cooling to slow growth. It is also beneficial to allow juvenile hibernating species a short, controlled hibernation (for 2-3 weeks) to help control the rate of growth and then increase the length of hibernation time yearly as the juvenile grows (McArthur and Barrows, 2004).

Tortoise Hibernation Plan

Species that can be hibernated

The Hermann’s tortoise, Testudo hermanni can be found across Europe. The maximum recommended hibernation period within captivity is 10-12 weeks.

 

The marginated tortoise, Testudo marginator can be found throughout Southern Greece. The maximum hibernation period is 10-12 weeks.

Iberas, Testudo ibera are found across Europe and Middle East. The maximum hibernation period is 10-12 weeks.

The North African species, Testudo graeca graeca are found in a wide range of habitats across Mediterranean Africa. This species will require a shorter hibernation period in captivity, no longer than 8-10 weeks. In the wild they will not be subjected to a long period of cooling.

 

The Horsfield’s tortoise, Testudo/Agrionemys horsfieldii is not classed as a Mediterranean tortoise but in terms of husbandry is closely related. They are the most Northerly living tortoise and therefore hibernate for long periods of time in the wild due to the cold temperatures. In captivity we recommend a hibernation period of 10-15 weeks.

Hibernation Assessment

As days grow shorter, temperature falls and light intensity decreases, tortoises prepare for hibernation. In order to survive hibernation, tortoises need to be healthy and to have built up sufficient reserves. For tortoises that do hibernate it is important to ensure that the tortoise is healthy enough for the process. We would encourage a pre-hibernation assessment before embarking on hibernation.

Hibernation Plan

Never hibernate a sick or underweight animal. Tortoises DO NOT need long periods of hibernation and ideally should never be hibernated for more than 3 months, and NEVER over 20 weeks which unfortunately has been a common finding over the years.

The best time to hibernate is from late November until late Feb when the temperatures are around 4.5-8°C. Outdoor tortoises will start showing signs of slowing down late August/September; indoor tortoises usually need owner intervention.

 

In preparation, the tortoise must not be fed for 3-4 weeks before hibernation (McArthur and Barrows, 2004). Fasting will slow the metabolic rate and it can take up to 4 weeks to empty the gastro-intestinal tract. During the fast, tortoises must have access to some heat during the day, for approximately 4-5 hours to aid in digestion of the remaining food within the stomach. Ideally the tortoise should have not been fed fruit as fruit skin takes longer to digest and will ferment if not eliminated before hibernation. Tortoises can die due to undigested food remaining in the gastro-intestinal system during hibernation and this will decay producing bacterial infections as well as large quantities of gas.

Hydration is essential and daily bathing in lukewarm water for 10-15 minutes is recommended for 3- 4 weeks before hibernation - this will also help tortoises void faeces.

 

The tortoise is ready to hibernate after 4 weeks of fasting when urine is clear and no more faeces are produced. Cool the tortoise to room temperature. The tortoise will appear sleepy, torpid and may have dug in to dry fallen leaves if kept outside.

Hibernation Methods

If all the pre-hibernation requirements are met then a healthy tortoise can hibernate with the following factors in mind; 1) the tortoise must be kept dry and well insulated and 2) the temperature must be stable and at the right setting (5°C).

Methods of hibernation:

BOX METHOD

 

Use a large, wooden, rodent-proof tea-chest or box, with small air holes in the sides. Cover the top and the holes with wire mesh to prevent rodents entering. The base and sides of the box should be lined with polystyrene or thick pads of newspaper. Place the tortoise in an inner box with air holes and fill up to three quarters full with shredded newspaper. Avoid hay or straw as it can harbour mould spores or other irritant substances. Place the tortoise inside the inner box and then place this inside the larger insulated box – make sure you can open it easily to assess the tortoise. The tortoise can be carefully weighed complete with inner box on a weekly or twice monthly basis. An adult tortoise loses about ONE PERCENT of its pre-hibernation weight A MONTH (ie a 2000g tortoise is allowed to lose 20g monthly). A drastic weight loss indicates something is wrong and the tortoise must be brought out of hibernation immediately and examined. Make sure the tortoise is hibernated in a frost- free environment, at temperatures of 4-8°C. Below zero degrees Celsius a tortoise can become blind and have damage to limb extremities. Above 8°C a tortoise becomes too active and will use up its energy reserves. A maximum-minimum recording thermometer should be used to read the temperature inside the inner box containing the tortoise. The box itself should be placed in a cool, dry area using the temperature of the inner box as a guide. The temperature must stay at 4-8°C and it is important to check daily.

 

Concerns of using this method would be that temperatures could drop to dangerous levels. If using this method it is better to place tortoise in a brick built building or shed with frost protector. A frost protector costs approximately £30-40 and set at 5°C, may-be a life saver. If this is not possible we would recommend placing a glass of water next to the tortoise box. If there are ice crystals in the glass then the tortoise has succumbed to too low a temperature. In this situation the tortoise needs waking up immediately and veterinary intervention.

 

 

FRIDGE METHOD

 

This is the preferred method as it accurately controls temperatures. Only new fridges should be used and ones without ice boxes. Ventilation is very important and can be provided by cutting a small hole in the top and bottom of the door seal or by opening the door daily to check the tortoise. The temperature should be set at 5°C and checked daily with digital thermometer probe. Ideally, use two digital thermometers in case one is faulty as cases where tortoises have been kept at too low a temperature due to a faulty thermometer have been reported. Provide them with soil to bury into and put a towel over them and put them in the fridge. By covering them with a towel it helps to block out the light when opening the door and also replicates the dark conditions in the wild. Some movement is normal during hibernation. A large number of tortoises will urinate in the ‘settling in period’ and if they pass a small amount of urine within the first three weeks then I generally do not get them up if they have been bathed daily for 3-4 weeks before hibernation. If tortoises urinate within month two or three of hibernation it is recommended to take them out of hibernation.

 

 

GARDEN METHOD

 

This is the most controversial captive method of hibernation and one that we do not recommend. In the wild tortoises will bury beneath the surface. In captivity they are subjected to flooding from waterlogged soil, freezing and rat attacks. If this method has to be used then only allow this in a greenhouse, with a soil base and cover the area where the tortoise has buried into the soil. Frost damage can cause trauma to the nervous system, eyes and frostbite to the limbs is a very common finding. Rat bites are also common in tortoises hibernated outdoors or in cardboard boxes within outhouses.

Summary

Whichever hibernation method used, temperatures must stay between 4-8°C, below 4°C may cause freezing and over 8°C uses up energy reserves too quickly and the animal wakes up. Tortoises will lose 1% of body mass a month, any more than this or if the animal has urinated during hibernation then they must be woken up.

Check List:

1. At the end of October increase time tortoise is spending outside (in outhouse) as this will allow exposure to shortened day length and a decrease in temperature or if inside, decrease the temperature. Aim for a decrease of 5°C core body temperature per week

2. STOP FEEDING but encourage bathing – bathe for 10-15 minutes a day to encourage good hydration, urination and defaecation.

3. Once body temperature is around 13°C the tortoise can be moved to a refrigerator or hibernation box as mentioned above. ENSURE FEEDING HAS STOPPED AT LEAST 4 WEEKS AGO.

4. Wake up from hibernation February or before. This will allow sufficient grazing time before next hibernation.

Emergence from Hibernation

From end of January increase the number of checks on the tortoise. As the ambient temperature approaches 10°C the tortoise will begin to wake up. When the tortoise starts moving take it out of hibernation quarters. Inspect eyes, nose and tail end for discharges. Bath the face and eyes – wash the mouth if possible. The tortoise should be encouraged to drink so give the animal a warm bath for at least half an hour twice a day. This also encourages the tortoise to expel any waste built up during hibernation. Tortoises should be kept warm with suitable temperature and UVB light provision until it gets warmer and they can spend time outdoors. Succulent ‘junk’ foods should be offered (start with melon and cucumber initially) to encourage appetite. Appetite, urination, activity, defaecation and thirst must be monitored closely. Weigh the tortoise as soon as it comes out of hibernation and compare this with the weight pre-hibernation. Most tortoises will feed within 24 hours. If the tortoise has not eaten or urinated within 5 days of emergence or appears ill veterinary intervention is essential.

Reptile Care  

Tortoises

 

Mediterranean Spur-thigh tortoise (Algerian spur-thigh tortoise Testudo graeca graeca, Iberian tortoise Testudo graeca ibera) (CITES Appendix II, Annex A)

Hermann’s tortoise (Testudo hermanni) (CITES Appendix II, Annex A)

Horsfield tortoise (Testudo/Agrionemys horsfieldii) (CITES Appendix II, Annex B)

 

These three species are the ones most commonly seen in captivity. Their placid nature makes them a popular pet.

 

Vivarium - they require an enclosure those sides are at least 5x the animal’s lenght. Wooden vivariums are preferable as they are an excellent insulator for heat. They also should have an excellent  ventilation. Thermometers should be placed in the hottest and coolest part of the vivarium to check temperature daily. There is also a selection of tortoise tables. There are certainly benefits of keeping tortoises outside (weather and temperature permitting) like unfiltered sunlight. They must be kept indoors in damp weather and during the pre-and post hibernation period.

 

Temperature - 20-28°C with basking area of 32°C. They need a lower temperature overnight. Basking bulbs should be on for 10-12 hours/day.

 

Humidity - 30-50%

 

UVA/UVB lighting - ultraviolet light does not penetrate glass or plastic; therefore it is imperative to place the UV light source inside the cage. The bulb should be changed every 6-12 months. In general it is recommended to place the bulb within 30 cm from the basking area but this distance might vary according to the manufacturer’s instruction. UVB light is essential for these animals so that they can produce vitamin D3. Without this vitamin they are unable to absorb calcium and can get illnesses like gastrointestinal stasis, cloacal organ prolapse, deformities of the limbs, spine, jaw, hypocalcaemic tetany etc.

 

Decoration, furniture, substrates - large stones, hides etc. can be used to allow the animal to use its space and retreat. Avoid heated rocks as they can lead to burn injuries. Also avoid living plants as they can be a source of germs but artificial plants can be used anytime. Soil (natural limestone or soil mix)with adequate depth is advisable to use, since it helps thermoregulation and shell development. Care should be taken that young tortoises (under 2 years) have to have access to this facility as they spend most time buried into the soil.

 

Nutrition and water -  they need vegetable diet which can consist of edible garden plants, flowers and grasses (more info on www.thetortoisetable.org.uk). Use vitamin/mineral powder supplements according to the manufacturer’s instructions. There is a possibility of using a natural limestone block. Provide fresh water every day in small tub and mist the vivarium once  a day. Bathing can be beneficial as well.

 

Chameleons

 

Yehmen or veiled chameleon (Chamaeleo calyptratus)

Panther chameleons (Furcifer pardalis)

 

These two species are the ones most commonly seen in captivity. They are well known for their ability to change colours. Chameleons are arboreal species which means that they prefer living above the floor on branches.

 

Vivarium - at least 2-3x the animal’s length, in height of the vivarium. Wooden vivariums are preferable as they are an excellent insulator for heat. They also should have an excellent  ventilation. Thermometers should be placed in the hottest and coolest part of the vivarium to check temperature daily.

 

Temperature - 21-38°C. They need a lower temperature overnight. Basking bulbs should be on for 10-12 hours/day, care should be taken to place the bulb at least 20-30 cm away from the highest branch or bulb guard should be used, otherwise burning injuries can be possible.

 

UVA/UVB lighting - ultraviolet light does not penetrate glass or plastic; therefore it is imperative to place the UV light source inside the cage. The bulb should be changed every 6-12 months. In general it is recommended to place the bulb within 30 cm from the basking area but this distance might vary according to the manufacturer’s instruction. UVB light is essential for these animals so that they can produce vitamin D3. Without this vitamin they are unable to absorb calcium and can get illnesses like gastrointestinal stasis, cloacal organ prolapse, deformities of the limbs, spine, jaw, hypocalcaemic tetany etc.

 

Decoration, furniture, substrates - secure branches and hides etc. can be used to allow the animal to use its space, climbe, retreat as well as they have functionality to aid shedding. Try to create a secure tree-top environment with lots of possibilities to climb. Avoid living plants as they can be a source of germs but artificial plants can be used anytime. Newspaper or kitchen paper towel is probably the best substrate, although not very naturalistic. Astroturf, washable carpet squares can be also sufficient enough, and they also retain some moisture which increases the humidity inside the vivarium. Woodchips are not very recommended as they can be toxic, allow pathogens to build up and can cause impaction if accidentally eaten.

 

Nutrition and water - chameleons are insectivorous which means they eat live prey. These can be gut loaded crickets, cockroaches or locusts, mealworms, waxworms. Gut loading (feeding the prey with a commercially available high calcium/multivitamin diet 48 hours prior to feeding) is very important to maintain the nutrition of our animal. Also vary the species to be fed from time to time. Always remove the uneaten prey, since they can cause bite injuries overnight. They also eat leaves/foliage in the wild which should be replaced in the vivarium with suitable sources. Mist the vivarium regularly, since they drink from water droplets on foliage and not from a bowl. The relative humidity should be between 75-80% (this can be checked with a hygrometer).

 

 

Bearded Dragon

 

Bearded dragon (Pogona vitticeps)

 

The bearded dragon is an Australian agamid lizard, is kept as a popular pet in the UK due to their nature. They are approximately 20-30 cm in length. Young ones require more feed of animal origin (e.g. mealworms, crickets etc.) than vegetables, but as they grow older the ratio shifts and they need more vegetables in their diet.

 

Vivarium - ideal size at least 3x animal’s length for the longest side of the vivarium by twice the animal’s length for the shortest side. Wooden vivariums are preferable as they are an excellent insulator for heat. They also should have an excellent  ventilation. Thermometers should be placed in the hottest and coolest part of the vivarium to check temperature daily.

 

Temperature - 25-35°C with basking area of 38-40°C. They need a lower temperature overnight. Basking bulbs should be on for 10-12 hours/day.

 

Humidity - 30-40%

 

UVA/UVB lighting - ultraviolet light does not penetrate glass or plastic; therefore it is imperative to place the UV light source inside the cage. The bulb should be changed every 6-12 months. In general it is recommended to place the bulb within 30 cm from the basking area but this distance might vary according to the manufacturer’s instruction. UVB light is essential for these animals so that they can produce vitamin D3. Without this vitamin they are unable to absorb calcium and can get illnesses like gastrointestinal stasis, cloacal organ prolapse, deformities of the limbs, spine, jaw, hypocalcaemic tetany etc.

 

Decoration, furniture, substrates - large stones, hides etc. can be used to allow the animal to use its space, climb and retreat as well as they have functionality to aid shedding. Avoid heated rocks as they can lead to burn injuries. Also avoid living plants as they can be a source of germs but artificial plants can be used anytime. Newspaper or kitchen paper towel is probably the best substrate, although not very naturalistic. Sand can be dangerous since it can lead to impaction of the gut system (even calci-sand). Avoid small stones and gravel.

 

Nutrition and water -  juveniles need 80% livefood of their diet. These can be gut loaded crickets, cockroaches or locusts, mealworms, waxworms. Gut loading (feeding the prey with a commercially available high calcium/multivitamin diet 48 hours prior to feeding) is very important to maintain the nutrition of our animal. Also vary the species to be fed from time to time. Always remove the uneaten prey, since they can cause bite injuries overnight. Adults need 80% vegetable diet which can consist of dandelion, clover, kale, carrot, parsnip, courgette, pepper. Use vitamin/mineral powder supplements according to the manufacturer’s instructions. Provide fresh water every day in small tub and mist the vivarium once  a day. Bearded dragons also like bathing in shallow water from time to time, so this activity can be part of a weekly routine.

 

 

Asian Water Dragon

 

Chinese or Asian  water dragon  (Physignatus cocincinus)

 

These beautiful creatures are arboreal, semi-aquatic lizards, which means that they prefer living above the floor on branches and they need a sufficient amount of water for their life quality.

 

Vivarium - at least 2-3x the animal’s length, in height of the vivarium. Wooden vivariums are preferable as they are an excellent insulator for heat. They also should have an excellent  ventilation. Thermometers should be placed in the hottest and coolest part of the vivarium to check temperature daily.

 

Temperature - 24-30°C. They need a lower temperature overnight. Basking bulbs should be on for 10-12 hours/day.

 

UVA/UVB lighting - ultraviolet light does not penetrate glass or plastic; therefore it is imperative to place the UV light source inside the cage. The bulb should be changed every 6-12 months. In general it is recommended to place the bulb within 30 cm from the basking area but this distance might vary according to the manufacturer’s instruction. UVB light is essential for these animals so that they can produce vitamin D3. Without this vitamin they are unable to absorb calcium and can get illnesses like gastrointestinal stasis, cloacal organ prolapse, deformities of the limbs, spine, jaw, hypocalcaemic tetany etc.

 

Decoration, furniture, substrates - secure branches, large stones, hides etc. can be used to allow the animal to use its space, climbe, retreat as well as they have functionality to aid shedding. Avoid heated rocks as they can lead to burn injuries. Also avoid living plants as they can be a source of germs but artificial plants can be used anytime. Newspaper or kitchen paper towel is probably the best substrate, although not very naturalistic. Astroturf, washable carpet squares or coarse orchid bark can be also sufficient enough, and they also retain some moisture which increases the humidity inside the vivarium.

 

Nutrition and water - water dragons are insectivorous which means they eat live prey. These can be gut loaded crickets, cockroaches or locusts, mealworms, waxworms. Gut loading (feeding the prey with a commercially available high calcium/multivitamin diet 48 hours prior to feeding) is very important to maintain the nutrition of our animal. Also vary the species to be fed from time to time. Always remove the uneaten prey, since they can cause bite injuries overnight. Provide fresh water every day in small tub or with a waterfall and mist the vivarium once  a day.