Winter Check for Mediterranean Tortoises

Sleepless for 16 years – at a beak trimming appointment, the owner of a Greek tortoise mentioned that the animal had never hibernated. The treating veterinarian asked in the expert forum small animals: “Should hibernation now be started for the first time? Any problems to be expected?’ medical vet Karina Mathes, a specialist veterinarian for reptiles and head of the reptile and amphibian department of the clinic for pets, reptiles, ornamental and wild birds of the University of Veterinary Medicine Hanover, advises that every healthy Mediterranean tortoise should be hibernated, even if it has not yet been carried out. Hibernation should be made possible from the first year of life, as this corresponds to the natural needs of Mediterranean tortoises and is essential for a regulated circadian rhythm. In this way, too rapid growth can be prevented and the immune system strengthened. Only in the case of sick, weakened animals does the hibernation have to be dispensed with or only carried out in a shortened form.

To avoid problems, a winter check with a clinical general and a fecal examination should be carried out no later than six weeks before hibernation. If treatment against parasites is required, wintering should not begin until six weeks after the last dose of medication, because the drug cannot be metabolized and excreted at low temperatures. A complete health check also includes an X-ray examination to detect, for example, diseases of the lungs, remaining eggs, or bladder stones.

In animals weighing more than 120 g, the blood should also be examined to be able to conclude the organ status of the animal, primarily based on the liver and kidney values ​​as well as the electrolytes.

The triggers for hibernation are a decreasing nighttime temperature and length of daylight. Autumn is imitated in the terrarium by gradually reducing the temperature and lighting duration over two to three weeks. After the animals have stopped eating, they should be bathed two to three times to partially empty their intestines. At about ten to twelve degrees Celsius, the turtles are then inactive and can be brought to the winter quarters. If an animal has not yet experienced hibernation and therefore does not want to sleep, autumn must be simulated particularly intensively.

The tortoises are placed in a hibernation box filled with humus-rich soil or sand and covered with beech or oak leaves. They dig themselves in. The box is then placed in a dark refrigerator with a constant temperature of around six degrees Celsius. Sometimes you have to put animals that have been professionally cooled down to about twelve degrees Celsius into the refrigerator relatively actively so that they finally bury themselves. Before the refrigerator is used as the turtle’s hibernation place, it should be running for a few weeks and fitted with a minimum-maximum thermometer to anticipate massive temperature changes. Wine refrigerators, which can be set to a constant temperature, are particularly suitable.

During hibernation, the substrate and air should be kept slightly moist, but mold must not form. The temperature should be checked daily. To do this, the outside sensor of a digital thermometer can be plugged directly into the substrate of the winter box. There is a weekly weight check and a short health check. Breathing, the reaction to touching, the nostrils for discharge, and the abdominal armor for visible bleeding are checked briefly. If the weight decreases by more than ten percent of the initial weight, the liquid loss is too high and the hibernation too dry. If necessary, the animal must be woken up early from hibernation.