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Although mating may not appear successful, time lapse may be the key. Some tortoise species have the ability to store sperm in their bodies for up to two years. This greatly increases the chances of successful conception. Many tortoises will indicate pregnancy in their temperaments. Some gravid, or pregnant, tortoises may suddenly undergo a personality change. Some will become aggressive toward other turtles in their enclosure or their keepers. Others may stop eating. When the time to lay is near they may begin to restlessly move about the perimeters of their enclosures. More methods of detecting pregnancy involve monitoring weight gains or, if a problem is suspected, X-rays (or more difficult, ultrasounds) may be utilized.
Gravid females will need an area where they feel comfortable laying their eggs or they can develop problems. Often in outdoor enclosures, a clean, raised, slightly sloping site may be preferred by the tortoise. Loose or sandy soil may also encourage nesting, provided it is not so loose that it cannot hold its shape. Many tortoises will accept a nesting box with plenty of substrate. Large tortoises may often prefer a deep substrate and may to dig extensively during nesting. Many times tortoises will dig "test" holes prior to actually digging and laying their eggs. When maintaining tortoises in groups, females may prefer certain nesting spots to others and may actually dig up previous nests, breaking the eggs. If this becomes a problem, you may find it is easier to isolate nest sites after they have been used.
Once the eggs have been laid, they may be removed to be incubated at a specific temperature, in order to ensure proper fertility. Find out the temperature at which your tortoise's eggs will need to be kept. Humidity levels may also be a concern. Most experienced tortoise breeders will have their incubator prepared and running before the animal lays. Usually an incubator is a simple closed box filled with a specified ratio of vermiculite and water to create an appropriate humidity. The eggs are placed inside. Some ventilation is needed, as the developing embryos will require some sort of oxygen exchange in order to survive. Many times the sex of the hatchling tortoises can be determined by the temperature at which they are incubated. The temperature can also determine how quickly the eggs will hatch. It may be advisable to keep a thermometer in the incubator to be sure that the developing turtles are kept at the temperature you desire. Carefully remove the eggs from the nesting site and place them in the incubator. Avoid turning or handling the eggs while they incubate. Unlike birds, reptile eggs must not be rotated or turned. For some tortoises maintained in outdoor settings, eggs deposited in the ground may hatch under natural conditions provided the habitat, temperature, humidity levels, and season are suitable. If your climate conditions are similar to the natural environment of the tortoise, you may choose to leave the eggs in the ground to hatch naturally. This is reported to produce babies with a better survival rate. If you do this, be sure to watch for predators such as dogs, cats, and large birds, who might prey on newly hatched babies.
When the young tortoises first hatch, they may be quite round in appearance. Their plastrons may also be folded. This is because they are curled up inside the egg. These conditions will fix themselves in a few days, as the turtles develop. Often tortoise clutches will not all hatch simultaneously; some eggs may take longer than others. This is a natural phenomenon that helps prevent predators from grabbing all of the babies as they hatch. Attempting to break the eggs to aid the late tortoises in hatching may be fatal for them. It is better to wait until the tortoises begin to hatch on their own. When they are ready, the young tortoises will poke a hole in their egg with their egg tooth, or egg caruncle, which will disappear in a few days. After making an initial opening, the little tortoise will continue to enlarge the hole by biting it and pushing with its front legs. The process may take a few hours, and some young tortoises will remain in the egg for days after they have made the first break. In this time, the tortoise will absorb the egg sac attached to it and will gain strength. Some young tortoises can become glued into their eggs by membrane residue or albumen. In this case, you may try very gently wiping the affected areas with sterile water on a cotton swab. After the tortoise has emerged from its egg, move it into a special enclosure at about the same temperature as the incubator. Gradually you may adjust the temperature to a level more suitable for the young tortoise. Place the eggshell in with it, as the little tortoise may eat it in order to absorb calcium crucial to its development.
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