Determining the sex of a bearded dragon can be challenging, especially for new owners, because the differences between males and females are not immediately obvious. Accurate sexing is important for various reasons, including appropriate housing, understanding potential health issues like egg-laying, and anticipating certain behaviors. Reliable physical and behavioral indicators become apparent as the reptile matures.
The Age and Size Requirement for Accurate Sexing
Determining the sex of a bearded dragon before it reaches maturity is unreliable. The physical characteristics used for sexing, particularly the hemipenal bulges, are not fully developed or visible in hatchlings and young juveniles. Most dragons need to be at least six to eight months old before the differences become distinct enough to observe accurately.
The most reliable physical indicators typically appear once the dragon reaches a snout-to-vent length of approximately six to seven inches. Waiting until the dragon is a sub-adult or adult, around 12 months of age, provides the highest certainty because the secondary sex characteristics are fully developed.
The Hemipenal Bulge Method
The most dependable method for sexing a bearded dragon involves examining the base of the tail for the presence of hemipenal bulges. Hemipenes are the paired copulatory organs found in male lizards, stored internally at the base of the tail. When the tail is gently lifted, these organs create two distinct, parallel bulges on the underside, just behind the cloacal vent.
To perform this check, place the dragon on a flat surface and gently lift its tail upward at a 90-degree angle from the body. A male will display two noticeable, elongated bumps running vertically down the tail base. A female will only show a single, central, and less pronounced bulge, which is the cloacal gland.
A variation of this technique, known as the “flashlight test,” can make the bulges more visible, especially in younger or darker-colored dragons. In a dimly lit room, shine a small, bright flashlight directly onto the top of the tail base, pointing toward the vent. The light will pass through the tissue, creating shadows on the underside of the tail. A male’s two hemipenes will appear as two separate, dark shadows, while a female’s single structure will cast only one central shadow.
Secondary Physical Indicators
Other physical traits can support the findings of the hemipenal bulge method, though they are not definitive on their own.
Femoral Pores
One such indicator is the appearance of the femoral pores, which are small glands located in a row on the underside of the rear thighs. Male bearded dragons have significantly larger, more prominent, and often darker femoral pores compared to females. The pores on a female are much smaller, less visible, and may appear as faint dots. A mature male’s pores look like a distinct line of small, raised bumps. These pores become most noticeable as the dragon reaches sexual maturity.
Head Shape and Size
Another secondary indicator is the shape and size of the head. Males often develop a broader, more robust, and more triangular head shape than females. The male’s head may also appear larger in proportion to its body size, and the spiky protuberances on the beard may be more pronounced. Females tend to have a narrower, more slender skull structure.
Behavioral Clues
Observing a bearded dragon’s behavior can offer additional, though less reliable, clues to its sex. Males are generally more territorial and frequently display behaviors intended to assert dominance. The most common is vigorous head bobbing, where the male rapidly moves its head up and down, often accompanied by a puffed-out, darkened beard.
Females are more likely to exhibit submissive behaviors, such as arm waving. This involves slowly rotating a front leg in a circular motion, which is a sign of deference. Behavioral observations should only be used to supplement the physical examination, never as the sole basis for sex determination.