Discovering that your pet lizard has deposited eggs is simultaneously thrilling and nerve-racking. On the one hand, you may be greeted with hatchling lizards in a few weeks; on the other hand, you must somehow devise a method for keeping them alive. The easiest way to tend to the eggs is to move them into an incubator, but few hobbyists have such tools. Alternatively, you can try to leave the eggs where they are and try to provide suitable conditions that will enable them to hatch.
To hatch eggs successfully, keep three criteria in mind:
1. You must keep the eggs at the appropriate temperature. While the appropriate temperatures vary from one species to the next, most eggs need temperatures between 80 and 90 degrees Fahrenheit.
2. You must keep the eggs at the right humidity level. The proper humidity level varies from one species to the next.
3. You must ensure the eggs do not rotate, as this can cause an embryo to drown. It is a good practice to place an “X” or a number on the top of each egg with a graphite pencil.
The term artificial incubation means that the keeper uses an incubator to hatch the eggs. In the vast majority of cases, artificial incubation produces better results than leaving the eggs to hatch in the cage because of the increased environmental control an incubator provides. Incubators are available commercially, although advanced hobbyists and breeders often construct their own. Either choice is fine, as long as the incubator maintains a consistent temperature and humidity.
Usually, keepers place the eggs in a small egg box, which is then placed inside the incubator. The egg box contains an appropriate substrate for the species, such as sphagnum moss, peat moss, vermiculite or perlite. Dampen the substrate slightly, but avoid making it too wet as standing water may harm your eggs. Place two small holes in the egg box – one for ventilation and the other to allow a thermometer probe to enter the box.
Incubating In Situ
If you do not have access to an incubator, you will have to try to incubate the eggs where they are. For species that bury their eggs in the substrate, this means re-covering the eggs to keep them safe and prevent them from desiccating. It is difficult to control the temperature of eggs buried in substrate, but you can place a digital thermometer probe with the eggs before reburying them. Then, do your best to maintain appropriate temperatures with basking lamps or heating pads; just be sure to keep the cage temperatures within acceptable tolerances for your lizard.
For lizards that deposit eggs out in the open, cover the eggs with a small deli cup to protect them. Place a small hole in the cup to provide a small amount of airflow, and place a slightly damp paper towel in the container to keep it from drying out. The cup will also prevent the adults from eating the hatchlings until you can move them to their own cage.