Breeding

Tortoise reproduction is different from mammalian reproduction. When mating takes place, 30 or 40 eggs are fertilized, of which six or eight grow to full size. Then shells are put on.

If the climatic and soil conditions are right, and the correct food is available, the female will dig a nest and lay them. If the conditions are not right, she will retain them until the conditions are right, and then lay.

After laying, another six or eight eggs grow. Further fertilization is not necessary. This process will continue until all the batch of 30 or 40 eggs is used up. Fertilized eggs will remain in the female indefinitely. Fertilized eggs will remain viable inside the female for about three years. This process enables the tortoise to mate at irregular, infrequent intervals and for the females to lay at regular intervals, when the soil is at the right temperature and humidity to hatch the eggs. The system works very well in their home (Mediterranean) climate, but in England difficulties often arise.

Do not attempt to mate different species. You will not be successful; the female will not enjoy the sexual harassment, and horrific cloacal damage can result.
Both Testudo graeca and Testudo hermanni have sub-species. Although it is possible to cross-breed the sub-species it is more difficult and may have undesirable consequences. It is better to mate each with their own kind.
Both the male and female must be fit and healthy.
Keep males and females separately. This is important, if you do not, the depreciation in health is generally sufficient to prevent eggs being viable.
Get the female X-rayed to check for retained eggs. If present, get them induced.
Increase the amount of calcium given to the female.
Make sure that your tortoise enjoy a good hibernation. A poor hibernation can reduce the sperm count of a male tortoise by up to 25%.