Most reptiles can hardly be considered doting, caring mothers. In the wild, most reptiles either deposit their eggs or bear their young and then take off, leaving the infants to fend for themselves.
The python snake is one of the exceptions. They tend to brook their eggs as they incubate, sometimes as long as 65 days. Once the eggs hatch, however, the mother moves on to bigger and better things.
For the majority of reptiles kept in captivity, their homes do not reflect their natural habitat. For this reason, eggs laid do not incubate as they would in the wild. In order to increase the chance of live young, artificial incubation is usually necessary.
Even though some lucky amateur breeders have successfully put eggs in a dark closet for several weeks to months for incubation, most reptile breeders use specially designed incubators. For an incubator to provide the proper environment, it is crucial to make sure good insulation and a reliable thermostat prevent the loss of heat and moisture, and to disperse heat evenly. Commercially available chick incubators with some modifications can work well. Substrates commonly used include vermiculite, potting soil, sand and sphagnum moss.
A double incubation chamber principle is used. A plastic waterproof container, such as a large sweater box, is partially filled with substrate and placed inside the incubator. Suspending the smaller container over the heat source provides a more even distribution of heat. One method consists of a layer of water in the bottom of the incubator with a submersible heater placed in the water. The smaller container is then suspended in the water by various methods such as the use of partial shelves or suspending blocks so that the evaporating water can provide the necessary humidity. Then it is topped by a lid with a small air vent and a window for viewing.
It's best to set up the incubator a few days before egg delivery to allow enough time for the heat to accumulate and disperse evenly. Place a thermometer in the middle of the substrate in the smaller container.
Once the eggs are delivered, they are placed in the substrate within the incubator. Be very careful not to rotate or change the position of the egg. This may or may not affect the developing reptile, but it is better to be safe than sorry.
Bury the egg halfway into the substrate and then moisten the substrate with water, being careful not to flood the area. Some breeders recommend covering the tops of the eggs with sphagnum moss to prevent drying of the eggs. However, this may hinder the ability to view the eggs as they progress. You should mist the eggs daily and check the temperature.
Incubation times vary from species to species, and are also affected by incubation temperature. Before beginning your reptile-breeding attempt, research your specific species to find out appropriate incubation temperatures and incubation times. By knowing when to expect emergence from the egg, you can help any babies that might have difficulty breaking through the egg, though this is rarely needed.