The tortoise is a living fossil, having survived since the dawn of the age of reptiles, 200 million years ago. Collection for exportation and habitat destruction have dramatically reduced populations in their native countries around the Mediterranean France, Spain, Italy, the former Yugoslavia, Turkey, Greece and areas of northern Africa. In Britain, with wet summers and cold damp winters, they are outside their distribution range, but if basic guidelines are followed, a captive tortoise can have as long and happy a life as possible.
TORTOISES AND THE LAW
In 1984 it was agreed with the now EU Council to treat three species of Mediterranean tortoise (the Spur thighed, Hermann's and also the Marginated Tortoise from Greece) according to Appendix I of the Convention for International Trade in Endangered Species (CITES). The Egyptian Tortoise (Testudo kleinmanni) was added to Appendix I in 1994 as was the African Pancake Tortoise (Malacochersus tornieri). This meant that these five species were protected and commercial trade strictly prohibited. For the sale, exchange or barter of these protected tortoises by private individuals a licence is required, obtainable from the Department of the Environment, Food and Rural Affairs (DEFRA) in Bristol. (See website: www.ukcites.gov.uk). This licence applies also to the selling of eggs but not to the giving away of either tortoises or eggs. When answering advertisements ask for the licence number. Commercial traders can be granted licences only if the tortoises are captive bred.
The ban does not apply to some tortoises from tropical and non temperate areas imported into Britain after 1984. Several box turtle species and subspecies are now included in Appendix II, as well as the Horsfield Tortoise (Testudo horsfieldi) from eastern Europe, which means trade is closely monitored.
COMMON CAPTIVE SPECIES
The species of Mediterranean tortoise most commonly imported into Britain have been the Spur Tortoise (Testudo graeca) and the Hermann's Tortoise (Testudo hermanni). The Spur thighed Tortoise is further divided into subspecies with a main division between Europe and northern Africa. They are in an active state of evolution and not fully understood. The Hermann's Tortoise, with two recognised subspecies, exists in the south of France, on the coastlines of Italy and the former Yugoslavia and on islands in the Mediterranean. The Spur thighed Tortoise has a spur on either thigh whereas the Hermann's Tortoise has a single horny claw at the tip of the tail (see diagram in centre spread).
In both species, the male can be recognised by the longer, narrower and more pointed tail (see diagram): some males have a concave plastron to facilitate mating.
A tortoise's body is surrounded by a protective shell with an upper part (the carapace) and a lower part (the plastron), both of which are made up of individual bony plates and horny scutes. The upper and lower parts of the shell are joined by bridges between the fore and hindlimbs.
The vertebrae of the backbone are fused to the carapace, as are the shoulder blades, ribs and pelvis. The lungs are located below the carapace, in the upper third of the body cavity, and below are the other body organs. During breathing the lungs are inflated and deflated by movement of the limbs.
Tortoises, like most reptiles, are ectothermic and rely on an external heat source (eg the sun) to raise their body temperature sufficiently for them to be alert, feed and digest their food. They become less active in cold weather.
Testudo hermanni (Hermanns Tortoise) - Female
Testudo hermanni (Hermanns Tortoise) - Male
Testudo graeca (Spur-thighed Tortoise) - Female
Testudo graeca (Spur-thighed Tortoise) - Male
HUSBANDRY AND HOUSING
Tortoises like roaming about, so if possible make the garden completely escape proof. Walled gardens are ideal but if you have to pen your tortoise in, allow at least 10 square metres per tortoise and make sure that the animal can neither climb over nor burrow under the surround. Pens with solid walls should be at least 50cm high, buried to a depth of 10cm, with wooden stakes as support. Garden ponds should be adequately covered to prevent risk of drowning.
A well ventilated greenhouse with access to a lawn and a paved sunbathing area is ideal for tortoises, as in both spring and autumn the animals will be able to heat up sufficiently to feed well, thereby extending their summer and shortening their hibernation period. A lower pane of glass can be replaced with a panel of wood with an entrance hole or cat flap in it, thus ensuring that the tortoises can escape from overheating on the hottest summer days. It should be remembered that glass filters out all of the sun's ultra violet rays.
Never attempt tethering a tortoise by string round the leg, which will cut off blood circulation and may result in gangrene, or by boring holes through the shell, which will cut through live tissue and cause pain or infection. Never attempt to oil your tortoise's shell.
A waterproof house in a sunny position is essential to protect the tortoise from extremes of cold, wet and heat. It can be of a wooden construction, preferably covered with roofing felt and be slightly raised to prevent the floor from becoming damp. It can be lined with thick newspaper or dried leaves. The house need not be very high as the tortoise will feel safer in an enclosed space.
All substrates used should be non abrasive, digestable, non toxic and easy to clean.
If you have several tortoises keep them in single species in groups of no more than five to reduce disease risk. It is advisable to separate the males and females as the males often engage in female shell butting and leg biting as part of their courtship. Females constantly exposed to this treatment, and unable to escape, will feed less, produce eggs less frequently and will eventually suffer from extensive shell and leg damage with an increased likelihood of infections.
Many commonly kept tortoises are basking species. These naturally use ultraviolet light from the sun's radiation to produce vitamin D. During the summer months exposure to unfiltered sunlight is ideal. At other times of the year supplemental lighting will be required. Artificial sources produced for reptiles should be used. UV light is split into a number of fractions and it is the UV-b which is required for vitamin D production. Many lamps marketed may be full spectrum or UV producing, but it is important to ensure that the lamp is producing UV-b. This should be on every day mimicking the natural daylength. Many lamps need to be close to the tortoises and need to be replaced frequently, even if they appear to be working as the UV light production falls over time and distance from the source.
Natural and Artificial Lighting for Chelonia.
Contrary to belief tortoises do drink, especially on waking from hibernation. A shallow dish about 10cm deep should be sunk into the ground. A cat litter tray part filled with water at 24°C can be used as a bath for 10-30 minutes. Tortoises placed in the bath should be supervised to prevent drowning.
Tortoises need a diet which is high in fibre, vitamins and minerals, but low in fat and proteins, and they feed mainly on green leaves. If your tortoise has the run of a garden it will forage quite successfully for itself on charlock, chickweed, clover, dandelion, groundsel, plantains, sow thistle and vetches, often complete with flowers, and the leaves of plants and bushes like buddleia, ice plant, lilac, rose and bramble. Make sure you have a tortoise friendly garden containing no poisonous plants. Propagate your own weeds if you can. Seeds are obtainable from various seed merchants. Beware of weed killers and slug pellets especially if foods are gathered away from your own premises. Always wash wild foods thoroughly before feeding.
At times of year when suitable weeds are hard to find a wide variety of greens and salad must be offered. The diet should be guided by the situation in the wild. Fruit is sometimes eaten but it should only form a minor part of the diet. Vegetables should be fed raw and in moderation. Avoid excess of one food type, such as brassicas, which should only be fed as part of a varied diet. If a tortoise is not eating, advice should be sought within a week.
In their natural habitat, tortoises are opportunistic feeders and they will occasionally tackle carrion and dung. Their digestive systems are, however, geared towards the digestion of cellulose, so high protein items like dog and cat food and peas are not natural and can be harmful, especially in juveniles.
Foods should be dusted with an appropriate vitamin and mineral supplement two or three times a week. The quality of supplements varies and advice from a reliable source should be sought. Calcium carbonate can be scattered on the ground daily to provide additional calcium especially for egg laying females as they have a far higher calcium requirement.
A pair of tortoises may mate. The gestation period is from thirty days to three years. The female may dig several trial nests in suitable mounds of warm friable soil and finally will deposit on average between 5-10 eggs. In the absence of an acceptable site or temperature for laying, the tortoise may become egg bound, in which case veterinary help will be needed. In Britain eggs need to be retrieved and placed in an incubator kept at a temperature of 28-32°C. Depending on temperature, the eggs will hatch after 8-12 weeks. The incubation temperature determines the sex of the hatchlings: this is called Environmental Sex Determination. At the lower temperature hatchlings will be males, at the higher end they will be female; average temperatures will produce mixed clutches. Hatchlings, although soft shelled at first, are fully developed, requiring no maternal care. They need access to an indoor tortoise table, indoor run or heated vivarium during cold and damp spells. If a vivarium is used there must be good ventilation, and if the front is glass the lower part must be covered to prevent the animals from trying to get out, thereby falling on their backs.
Only breed from healthy, compatible adult tortoises. If in doubt always get a health check from your veterinary surgeon.
Tortoises are susceptible to a variety of illnesses which will need the advice of a veterinary surgeon, Runny nose, mouth rot and parasite infestation are infectious and require isolation.
- Discharge from the nostrils and watery eyes can be due to rhinitis, sinusitis or runny nose syndrome. The symptoms may progress from upper respiratory tract disease to pneumonia in the lungs.
- Stomatitis (mouth rot) is often seen post hibernation. It appears as a general inflammation or caseous (cheesy) material attached to the tongue, mouth and throat.
- Osteodystrophy (soft shell) can result from a combination of calcium deficiency, incorrect lighting and excessive protein in the diet.
- Diarrhoea is a sign of ill health, husbandry problems, a dietary imbalance or parasites. Check for undigested food, mucus or worms in faeces.
- Blindness or disorientation after hibernation can be caused by frost damage. The tortoise shuffles in circles and does not feed.
Refusal to eat is natural in the month before hibernation, cold weather and gravid females. It can also relate to stress and disease including stomatitis, ear abscesses, severe systemic disease (liver or kidney) and heavy burden of ascarid worms. There should be a thorough health check and evaluation of husbandry.
During August and September, as the days grow shorter, the light intensity decreases, the temperature begins to fall and tortoises prepare for hibernation. Feeding declines: it takes 4-6 weeks for their gut to empty, and before they start this process in early September the tortoises need a check over.
Make sure there are no signs of wounds, abscesses or other infections, and also that the mouth is clean and pink, the eyes alert and bright. As a rough guide the Jackson ratio can be used but preferably accurate weight records should be kept that can be checked from year to year. Ensure that the area around the tail and cloaca is clean.
Any tortoise which is underweight or suffering from an ailment should not be hibernated, but overwintered on an indoor tortoise table, or in an indoor run or vivarium. This should have a heat source and full spectrum light for 13-14 hours to prevent hibernation. The temperatures should be 26°C by day and 18-22°C at night. Fresh food and water should be provided. Never allow the temperature to go below 15°C.
THE HIBERNATION QUARTERS
If in a garage, shed or other frost free outhouse use a large, wooden, rodent proof tea chest or box, with small air holes in the sides. Both the top and the holes should be covered in wire mesh to prevent vermin entering. Line the base and the sides of the box with thick pads of polystyrene or newspaper. Place the tortoise in an inner box with air holes and filled to about three quarters with polystyrene chips, dry leaves or shredded newspaper. Avoid hay or straw. Place the smaller box inside the larger one, making sure it can be opened easily for check ups.
Alternatively the fridge method can be employed. Here you need a larder fridge (no freezing compartment at the top) and the temperature needs to have been monitored for at least a month before the tortoise is put inside on the shelf. The ideal temperature is 5°C. The door of the fridge needs to be opened at least once a day to allow for an exchange of air. The tortoise can be put in a box, or wrapped in a towel. The tortoise can be carefully weighed on a weekly or twice monthly basis.
An adult tortoise loses about 1% of its pre hibernation weight so a 1000g tortoise is allowed to lose 10g monthly. A drastic weight loss or urination indicates something is wrong: the animal should be brought out of hibernation immediately and checked.
Make sure the tortoise is hibernated in a frost free environment, at temperatures of 4 - 8°C. Tortoises kept below freezing point can lose their eyesight or at worst their lives. Use a maximum minimum thermometer (obtainable from garden shops) to check temperature changes.
For every drop of 10°C the heart rate drops 50%. At 4°C the respiratory movements are negligible. If the tortoise is kept too warm and becomes too active it will use up its fat and store of glycogen or animal starch in the liver; the latter is needed on emergence from hibernation.
EMERGENCE FROM HIBERNATION
Tortoises should be checked regularly especially from the end of January. When the animal starts moving take it out of its hibernation quarters.
- Bring it out of hibernation slowly., check for discharges from the nose and tail end.
- Inspect it carefully, bathe the face and eyes and wash the mouth.
- Give the animal a warm bath for at least half an hour. It is important that the tortoise empties its bladder to get rid of the toxic waste accumulated during hibernation and that it replenishes its water supply by drinking.
- Keep the animal warm during the day and indoors overnight until the nights get warmer.
- Once out of hibernation and eating, keep it active (as for overwintering) if the weather becomes cold again. Warm spells in February breaking hibernation are a hazard of the British climate.
Any tortoise not feeding or appearing ill should be taken to a veterinary surgeon without delay.
You can obtain further information on tortoise and terrapin care by consulting this website or by writing to:
British Chelonia Group, PO Box 16216, Tamworth, Staffordshire B77 9LA. Please enclose a SAE.