How to Incubate Reptile Eggs
One of the most exciting parts about keeping reptiles is breeding them and hatching out babies. One of the most important steps in breeding is incubating the eggs, which is something that I receive a lot of questions about. So i'm going to talk about some of the basic principals behind incubating reptile eggs but more specifically for this article I will be talking about leopard gecko eggs. But the basic principals apply to a lot of species, however it's important to do your research on whatever species your breeding to know the specifics on incubating their eggs. Many commonly kept reptile species lay eggs, with some exceptions like boa constrictors which are live bearers. Incubating eggs is a big part of reptile breeding and there are some things you want to keep in mind when doing it.
Firstly the humidity, eggs must be kept humid enough where they will not shrivel up and dry out but not too humid that they get moldy or wet. The sweet spot of humidity for leopard gecko eggs is achieved by using vermiculite or perlite (or a medium like those) and getting it wet enough that it compacts into a ball when you squeeze it but no water drips out. If water drips out it's too wet and if you can't make it into a ball that sticks together it's too dry. This for me has been the easiest way to get the right humidity but another way a lot of people use is to measure out water and vermiculite and do a ratio of the two. This can get more complicated and can take longer so I suggest the way I explained it earlier. It's the way I did it when I first started breeding reptiles and it has worked ever since.
The next thing to consider is the incubation temperature, which can vary depending on species but is usually between 75-95 degrees in most cases. For leopard geckos you want to incubate them anywhere between 80-90 degrees. One unique thing about leopard gecko eggs is that they are temperature sex determined meaning if you incubate them at 80 degrees they will be mostly females and at 90 degrees they will be mostly males. This is not will all species however, but it is great with leopard geckos because you can kinda choose what sexes you want. Not only does it effect the sex but it also effects the time it takes for them to hatch. At 80 degrees it will take longer around 60 days where at 90 degrees it will take around 40 days for them to hatch.
Next to regulate the temperature consistently and effectively you are probably going to want a incubator, If you only have a few eggs you can use a small commercial incubator like a hovabator or other similar models, which are essentially a Styrofoam insulated boxes with a heat coil. Alternatively for a small amount of eggs you could use a Styrofoam box and use a heat mat or heat tape with a thermostat to regulate it. This can be a very inexpensive way to make an incubator instead of buying one.
The next thing to consider is the container that you are incubating them in. Usually you would use a plastic deli cup or Tupperware food container, I use small deli cups. For air exchange I poke one small hole in the side of the deli cup and that's it. (The size of the hole is about the size of the point of a pen) Some people choose to not poke any holes and open the containers every few days to allow air exchange. I prefer just having a very small constant air exchange and not having to open containers. The small hole allows for enough air to let the eggs breath but not enough to dry out the incubation medium, which you don't want.
The last thing is time and patience. Once you do all of that and get your eggs in the incubator all you can do is wait! Usually you are going to have to wait between 40 and 90 days for reptile eggs to hatch. It's a good idea to check on the eggs every few days and check often right before they are expected to hatch so you can see them hatch and care for the hatchling. When checking on the eggs it's important not to disturb them or rotate them (in most species this will drown the egg and kill it.) But you should check for any mold growth or humidity issues. For example if you see an egg denting(and it's early in the incubation) the humidity is probably to low. So to raise the humidity you can add a drop or two of water to the bedding. If you notice mold growth then you can wipe off the egg, however mold can also be caused by infertile eggs so if you have mold and the humidity is good most likely your egg is infertile and it should be discarded if with other eggs to prevent the mold transferring to the other eggs.
- Rohman Taylor