Sometimes snake owners want to know how to determine the sex of their snakes. The problem is that judging whether a snake is male or female is not as simple as it is with many other animals. Male and female snakes can look very similar. However, with a little experience, there are a few ways to distinguish between them.
The following methods for determining a snake's sex should only be performed by an experienced handler or veterinarian. If you are new to snakes and want to know the sex of your snake, please have an experienced reptile keeper or veterinarian demonstrate these methods to you. Improper handling may injure the snake.
Tail features
Male snakes have a pair of tubular hemipenes (sexual organs), usually located inside their bodies. They are essentially two small penises, securely stored inside the snake's tail. Female snakes do not have hemipenes.
The hemipenis is located below the cloaca (vent) opening and runs down the tail on either side of the snake's midline. Because these sex organs are located inside the male snake, they may not be immediately obvious. However, there are clear clues indicating their presence. You can examine the shape and length of the tail to help determine if your snake is male.
The male's tail (the part of the snake that begins at the cloaca opening) is thicker and longer than the female's. It also tapers in a different way—it starts thicker and then tapers abruptly to the tip. The female snake's tail is generally thinner and shorter than the male's, and tapers evenly towards the tip.
While the differences can be quite significant when comparing snakes side-by-side, it can be difficult to determine a snake's sex without males and females available for comparison. This is why the following methods are more commonly used than looking at tail features for accurate sex identification.
Detection
Exploring a snake requires inserting a thin metal rod (called a snake probe) into its cloaca while the snake is awake. This special probe can be further inserted into the male, as there are hemipenes on either side of the vent in males. The probe will fall into one of these spaces pointing towards the tip of the tail.
When probing a female snake, the probe won't go too far into her vent. This is because when you point the probe at the tip of her tail, there's no room for it to move. Females have very little space in their scent glands.
Imagine two long stockings placed inside the tail of a male snake, spread open at the snake's vent. You can then see the hemipenis. If the snake is male, the lubricated probe will slide into the vent towards the tail and into one of the hemipenis located on either side of the tail.
If it is a female, the probe will only shed one to three scales on average.
In males, an average of nine to fifteen scales will be lost.
The difference in probe size between sexes is quite significant. For larger snakes, the probe is actually placed in more pockets.
Snake probing should only be performed when someone can hold the snake still, has a snake probe of the appropriate size, and is confident in performing the probe carefully and correctly. You do not want to harm your snake. If you are unsure how to perform this procedure safely, you should not attempt it.
ejecting half penis
If you don't know what "pop-out" hemipenis means, this term might scare you. Technically, it means temporarily restoring them to their original position so that they are visible outside the tail (which is what happens when a hemipenis prolapses). To do this, apply firm but gentle pressure with your fingers below the snake's vent, and the hemipenis will protrude from there. If done correctly, the hemipenis will pop out.
This method is typically only suitable for smaller snakes like ball pythons, and can cause significant trauma if not performed correctly. It's not the preferred method for determining a snake's sex because it's difficult to do. Additionally, you might not know if you're simply unable to eject the hemipenis, or if the snake lacks a hemipenis (indicating it's female).
