dragon facing out and lying flat on the palm of one hand while gently bending the dragon’s tail above the body plane with the other hand. We can’t emphasize enough that you must perform this task gently to avoid harming the dragon. Carefully bending the tail toward the ceiling, above the body plane, will cause the skin on the ventral side (underside) of the tail base to be stretched back, which will show the outlines of hemipenal bulges in males. These bulges run directly caudal (toward the tail) from the vent (cloacal opening). A defined, central post-anal groove—two vertical bulges with a channel running between—is a good indicator of a male,. In females, slight post-anal bulges may be visible, but they tend to run laterally from the vent, midline, like the arms of an inverted V. A probable female can appear flat right above the vent or can show one small bump. This method works best with experience and is usually complemented by other concurring observations, such as the male’s thicker tail and wider cloacal opening.
When sexing subadult and adult bearded dragons, you can apply the same method of raising the tail as described for sexing babies. As with babies, extreme gentleness is a must. Subadult and adult dragons can also be accurately sexed by pulling back the vent flap and exposing the cloacal opening. In males, the cloacal opening is significantly wider and larger than in females. Assessing the cloacal opening in babies is ineffective because males need to be older before the greater cloacal width becomes clearly noticeable.
In an adult male, you can evert one of the hemipenes by applying pressure with a thumb to one side of the tail base and rolling up toward the vent, which should cause a hemipenis to protrude. This process requires experience to perform properly and is sometimes applied to determine the sex of small bearded dragons, but it is not recommended because of the high risk of injury from crushing trauma if not performed with the proper level of experience and sensitivity. It is usually unnecessary to go to extremes to determine the sex of adults.
Many adults are also easy to sex from secondary sexual characteristics, including the aforementioned thicker tails/less tail taper and enlarged femoral pores in males. Also, adult males develop larger and broader heads as they mature. Males will also “display,” which means they show a dark throat (beard) and head-bobbing behavior, especially during the breeding season.
Life Stages
Bearded dragons undergo six life stages. Understanding these life stages is important to successfully raising and maintaining bearded dragons for long, happy lives. The six life stages, with corresponding sizes and/or ages, are as follows:
1 Embryonic/prebirth (fifty-five to seventy-five days): In captivity, this period of development, which occurs within the confines of the egg, is usually spent in an incubator. However, genetics, diet, health of the mother, and incubation conditions can all play roles in health at this stage. These factors are of concern to breeders and deserve further study by scientists.
2 Hatchling (birth to about 5 inches long): Newly hatched babies are acclimating to life outside the egg. The first few days are a rest period and then, over the following few weeks, babies learn to drink, find small prey, and develop a routine of basking, eating, and sleeping.
3 Juvenile (5–13 inches long): Stages 2 and 3 are characterized by ravenous appetite, frequent feeding, rapid growth, and a tendency to mutilate other young dragons, including nipping off tail tips, toes, or other low extremities, when food is insufficient. I’ve seen a hungry 6-inch bearded dragon try to eat its lifelong cagemate, which was only 4 inches long. It couldn’t swallow the smaller dragon, but it did crush the victim’s skull, killing it.Eating and growing are the primary concerns of Stage 3. In this stage, dragons frequently perform arm-waving behavior, a type of appeasement and intraspecies identity display. A social hierarchy based on feeding vigor/assertion and growth develops into two levels: the tough, big, aggressive feeders and the shy, small, “feed after the others” individuals.The primary differences between Stages 3 and 4 are size and behavior. Stage 3 begins when the young dragons reach a length of 5 to 6 inches. Mutilation tendencies toward animals in the same size range continue. By Stage 4, cannibalistic tendencies greatly decrease, as does the frequency of arm waving, especially in males. Dragons grow rapidly and eat a greater percentage of plant matter. A pattern develops: the bigger a dragon grows, the more it eats, so the more it grows, and so on. Social behaviors are still limited and, if enough food is provided, mostly passive.
4 Subadult/adult: (13–22 inches): Stage 4 lasts through the first three years of breeding activity. This socially interactive stage is characterized by a greater range of social behaviors, which are triggered by sexual maturity. The onset of sexual social behaviors results in well-defined hierarchies, with an alpha male becoming ruler of the roost. Males perform courtship, territorial, aggressive, and breeding behaviors. Females perform slow head-bobbing behaviors or push-ups to reveal their identity. Females also display submissive arm-waving behaviors during breeding. Growth rates at this stage decline because of hormonal changes and the diversion of energy and nutrients away from growth and toward breeding. Dragons achieve their adult length during this stage. The second year of Stage 4 will bring an increase in girth but usually no increase in length. After the onset of Stage 4, bearded dragons normally go through a brumation (winter shutdown period) annually.
5 Mature adult (fourth year of breeding until five or six years old): A gradual decrease in reproductive rate and little, if any, significant growth is associated with this stage of a bearded dragon’s life, which lasts two to three years.
6 Old age (usually by six to seven years of age): This stage is characterized by little or no breeding, at least in females. There is no measurable growth. Eventually, old bearded dragons enter a terminal stage of decreased feeding and increased lethargy that, over weeks or months, leads to death. It is wise to cut back on calories (but not all nutrients) with old dragons and pay special attention to providing adequate levels of water as well as comfortable surroundings and stress-free days.
How Fast Do Bearded Dragons Grow?
In one experiment, we raised a group of baby bearded dragons indoors, using basking lights (basking sites of 95° F) and twist Vita-Lite fluorescent full-spectrum bulbs within 6 inches of the dragons. We offered insects to the dragons three times a day and had a variety of plant matter available all day. We kept the lights on for sixteen hours daily.
The hatchlings averaged just under 4 inches in length when the experiment started. After fourteen weeks, the largest specimen had reached a total length of just over 14 inches. The smallest was 11 inches long.
The male’s larger, broader head is easier to distinguish in adult dragons.
Baby bearded dragons acclimate to life inside their enclosure.
The rate of growth can also be affected by the quality of feeder insects. At Fire and Ice Dragons, we conducted a similar experiment by raising babies from hatchling to eight weeks on different feeder insects. We fed one group gut-loaded crickets and greens, and we fed the second group Phoenix Worms (the originators of black soldier fly larvae) and leafy greens. We raised both groups under a ReptiSun 10.0 UVB bulb at a distance of 12 inches. By the end of eight weeks, the cricket-fed group reached an average length of 7 inches, while the group fed Phoenix Worms reached an average of 9 inches.
As a general guide, under this kind of intensive rearing regimen, growth will average 2–2½ inches a month for the first six months, and males can reach
