How to Sex a crested Gecko, A Crested Gecko looking at camera

How To Sex A Crested Gecko: 4 Simple Methods

The process for sexing a crested gecko can be confusing at first, but it’s straightforward once you know what to look for. 

This guide will help owners understand if they have a male or female crested gecko using a variety of methods.

Why It’s Important To Know If Your Crested Gecko Is A Male Or Female

There are many reasons why you’d want to know whether your crested gecko is male or female. For most reptile owners, sexing is a matter of curiosity. You want to know what gender you’re dealing with so you can provide a proper name!

But there are plenty of care-related reasons to know as well.

Male and female crested geckos don’t always cohabitate in peace. So, when you want to keep multiple geckos, knowing their sex is important.

Male crested geckos are notoriously territorial. Females can exhibit many of the same traits, but males are far more likely to cause trouble. They can get aggressive with others, increasing the likelihood of in-fighting and injuries.

You should never keep two male crested geckos together in one enclosure. Some reptile enthusiasts manage to house males together, but it requires having a massive terrarium to ensure every lizard has its space. We don’t recommend trying that, especially if you’re relatively new to the hobby. Most experts would agree that housing males together is a no-no unless you have many years of experience.

It’s possible to keep multiple females together. Furthermore, you can keep one male with several females, provided you have a spacious enclosure. Aggression is still possible, but the chances of issues arising are much lower than if you were to force two males to live together.

Another reason you need to know the sex of your crested gecko is to prepare for possible health issues. Males and females have distinct reproductive systems, so their susceptibility to specific ailments differs.

For example, females can lay infertile eggs without ever contacting a male. She can also experience egg-binding, which is a potentially life-threatening issue. Knowing that you have a female crested gecko makes you aware of those risks, ensuring you can provide the proper care if those health problems occur.

How To Sex A Crested Gecko

There are several ways to sex a crested gecko. Some are more effective than others, but the goal when using these gender identifiers is to look at the bigger picture. Observing each of the following traits can help you determine whether you have a male or female, allowing you to provide the best care possible.

1. Hemipenal Bulges

One of the most reliable ways to gender a crested gecko is to look for hemipenal bulges. These bulges are exclusive to the boys, so seeing them is a telltale sign you have a male crested gecko.

The hemipenal bulges house the hemipenes, the male reproductive organs for crested geckos. The lizard uses the hemipenes to pass sperm during mating.

Outside of mating, you won’t see the hemipenes. They’re usually tucked inside the body in the hemipenal bulge. The fleshy organ only comes out during mating. However, you can still see where they are.

To look for hemipenal bulges, you’ll have to observe the area below the vent. Males will have a prominent bulge just above the base of the tail. In some lizards, it’s a single uniform bulge. But in others, you might see some separation.

Either way, the hemipenal bulges are a reliable method of telling if you have a male or female crested gecko. They’re quite obvious, and you can often see them without handling your gecko. The prominent mounds are usually visible even from the side.

Females lack hemipenes. Therefore, they don’t have hemipenal bulges! The same area on a female will look smooth and flat.

Keep in mind that the hemipenes don’t develop until your crested gecko approaches maturity. It’s like puberty in humans.

Juveniles won’t have hemipenal bulges. They usually begin to develop when the gecko reaches about six months old. Before then, you can’t reliably gender these lizards using the appearance of hemipenal bulges alone.

2. Preanal Pores

Another way to differentiate between male and female crested geckos is to look for preanal pores. This trick isn’t as easy as observing the hemipenal bulges. The preanal pores are much more subtle, but it’s a good way to confirm the sex.

Preanal pores are what male crested geckos use to secrete pheromones during mating season. The lizard uses the pheromones to attract females and mark their territory to alert other males of their presence.

The pores are another male-exclusive trait, so seeing them indicates you have a male gecko.

You’ll need a magnifying glass or a high-quality camera to find the preanal pores. They’re difficult to see with the naked eye and look very similar to other scales. With a magnifying instrument, you should see tiny pores that look slightly different from the surrounding scales.

The preanal pores appear on the underside of the males, creating a line just above the vent. This line stretches from the inner thigh of one rear leg to the inner thigh of the other.

If you see the pores, you have a male.

While they are difficult to see, identifying the pores can help you sex your gecko before they reach maturity. The preanal pores develop sooner than the hemipenal bulges, so you can use them for sexing juveniles.

3. Femoral Pores

The femoral pores serve the same purpose as the preanal pores. They secrete pheromones your crested gecko will use to attract mates and establish their territory. Like the preanal pores, the femoral pores only appear in males.

These pores are just as difficult to see, so take out your magnifying instrument.

You’ll find these pores on the underside of the rear inner thighs. They form a small line in the center of the inner thigh and look slightly different from the other scales covering the leg.

4. Size & Build

Finally, you can look at your crested gecko’s size to determine their sex. This sexing technique is less reliable than the others because every gecko is unique. But if you have a small group of geckos, you may gain more insight by comparing their size and build.

Male geckos tend to be bigger than females. Both sexes can reach lengths of 8 to 10 inches from snout to tail tip. However, males are more likely to reach the upper end of the size scale.

They’ll also have somewhat bulkier builds. Males are usually more muscular, resulting in a stockier profile. They also have broader heads.

Females are slimmer and usually slightly smaller.

Again, you shouldn’t use size and build alone to differentiate between males and females. There are stockier female geckos and slimmer males! But comparing sizes can give you a better idea.

The best approach is to use size as your initial sex marker. Then, you can look for the presence of the pores mentioned earlier and the hemipenal bulge for confirmation.

The Problem With Using Cloacal Spurs To Sex Crested Geckos

You may read about cloacal spurs being another way to sex crested geckos. However, there’s a lot of misinformation about these unique biological characteristics.

The cloacal spurs are two triangular-shaped appendages that protrude from both sides of the vent. Experts aren’t exactly sure what these spiky spurs do, but one theory is that they play a part in mating behavior.

Either way, you can’t use cloacal spurs to determine sex. Contrary to popular belief, they’re not a male-only characteristic! Some reptile keepers say that only males have them, but that’s false. Females can have cloacal spurs, too.

Indeed, males usually have larger and more prominent cloacal spurs, but many exceptions exist. The truth is that every crested gecko is different, and you can easily find females with larger spurs.

Using cloacal spurs to sex your geckos is not a reliable technique. Looking at the other characteristics we mentioned earlier for more accuracy is better.

General Similarities & Differences Between Crested Gecko Genders

Male and female crested geckos look very similar to the untrained eye. That’s especially true when they’re young. Hatchlings and juveniles are nearly impossible to sex without super-close observation of those femoral and preanal pores.

You can’t see the differences until they reach six months old when the hemipenal bulges develop in males.

However, males and females have many similarities even through adulthood. They both have a similar look. While males are often slightly larger, it’s not by much. Furthermore, it’s not unheard of for females to outgrow their male counterparts!

All geckos are different; you can’t determine the sexes from a glance alone. Unlike other reptile species, the crested gecko doesn’t have obvious sexual dimorphism. Males and females have the same general shape, coloration, etc.

That said, there are some clear differences in biology. Because the two have different reproductive organs, they also have health problems you must be wary about.

For males, there’s the risk of hemipenes prolapse. For females, it’s egg binding.

In terms of lifespan, both genders can live for several decades. The average life expectancy for a crested gecko is 15 to 20 years. In rare cases, they’re also known to live closer to 30 years!

However, males are more likely to reach the upper end of the life expectancy range.

Male vs. Female Crested Geckos: Are There Ever Behavioral Differences?

You may notice some behavioral differences between male and female crested geckos. Some reptile keepers out there swear by those differences, but experts will tell you that the behavioral differences are not consistent.

You might hear that males are more outgoing than females. Many say that females are more reserved and shy than their male counterparts. But that’s not a consistent rule you can rely on.

There are plenty of outgoing females! Some will also be aggressive. By the same token, you might come across a male who’s more reserved and shy.

All crested geckos are different. They have unique personalities like any other pet you might have, so determining a lizard’s sex by behavior alone is not reliable.

As mentioned earlier, males have a greater chance of territorial behavior. The boys tend to be more protective, and housing two males together is never a good idea. Unless you have a massive enclosure where the males can stay separate, there’s always a risk of aggressive behavior.

However, you shouldn’t assume that females won’t do the same!

Generally, it’s fine to keep multiple females together. You can even house several females with a single male.

But you need to determine if that’s a good choice for you on a case-by-case basis. Females can cause just as much trouble as males, so you must observe how your geckos react in the presence of others to avoid any unnecessary drama and aggression.

The Correct Way To Handle A Crested Gecko When Determining Its Gender

When sexing a crested gecko, you need to be mindful of its comfort. Most of the telltale signs you’ll use to gender a crested gecko are on the underside of its body. Therefore, you may need to put your pet in a strange position to make the necessary observations.

Before you do anything, ensure you have a good bond with your geckos. Crested geckos need time to get comfortable with you before they trust you enough to handle them.

When preparing to examine your gecko, be patient and gentle. Gently lift the lizard from its enclosure, supporting its entire body.

Pay attention to its reaction. Crested geckos can drop their tail when they feel stressed and threatened. But unlike other gecko species, crested geckos can’t regrow it! If your lizard tries to wriggle out of your hands or goes into panic mode, return them to the comfort of the enclosure and try again later.

If your gecko is comfortable, gently tip their body and have a friend take photos of their underside. Observing pictures is a much better approach than putting your gecko in an uncomfortable position for too long.

Avoid putting your lizard on its back. Instead, tilt the body up to view the vent area.

Alternatively, you can observe your lizard while they’re lounging in the terrarium. In most cases, you can see hemipenal bulges from the side.

Is It Possible To Impact The Likelihood Of Your Crested Gecko Being A Male Or Female?

You can’t influence the likelihood of getting a male or female crested gecko.

Some species, such as the leopard gecko, have temperature-dependent sex determination. They lack the sex chromosomes that determine gender. As a result, breeders can influence the sex of hatchlings by adjusting the incubation temperature.

That’s not possible with crested geckos. These lizards have a ZZ/ZX chromosome system. Most geckos will have an even mix of males and females, and the gender of each hatchling is determined during conception.            

Conclusion

Now that you know how to sex a crested gecko, take some time to do a thorough inspection of your pet. Once you know what to look for, it shouldn’t be too difficult!

If you have any thoughts or questions, you’re more than welcome to send them over.