How to Tell If Crested Gecko Eggs Are Fertile?

It’s normal for some eggs to be infertile, even in a clutch from a healthy pair of crested geckos.

But how you can check this?

Well, there are two ways to identify if your crested gecko’s eggs are fertile or not.

Both are easy but the first one is the most reliable and accurate.

Here’s the lowdown of both methods:

Method 1: Candling

As I mentioned, this is the most reliable way to determine fertility.

Here’s how you can do it:

  1. Get a light source: An LED flashlight with a strong beam works well. You can also use a dedicated candling device specifically for eggs.
  2. Darken the environment.
  3. Handle carefully: Crested gecko eggs are delicate. Pick them up gently and try not to rotate them, as this can potentially harm a developing embryo.
  4. Shine the light through the egg: Now carefully position the egg in front of the light source.

Now first look at the below image.

After that, check for these signs of fertility.

  1. Reddish “Bullseye”: A developing embryo forms a ring of blood vessels that can look like a reddish target from above.
  2. Network of veins: Blood vessels will start to form a network throughout the egg.

Also, check if you find a dark mass!

In later stages of development, you’ll see a dark mass inside the egg, which is the baby gecko.

And this is an infertile egg:

2nd Method (Less Reliable)

First, look at the shape!

Fertile eggs tend to be slightly more plump and oval-shaped compared to infertile ones, which might be dented or misshapen.

Additionally, fertile eggs tend to be a healthy white color.

Infertile eggs may turn yellowish or off-white and may develop mold.

Don’t candle the eggs immediately after being laid. Wait at least a few days, preferably a week, to allow the embryo to start developing. Candling too early can be inaccurate.

Hope this makes sense!

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