Chapter 6 of 9 · Bearded Dragon Care Guide
Breeding
Disclaimer: I'm not a veterinarian and I don't hold a degree in animal science or animal care. This guide is compiled from the published sources listed in every chapter. For a sick animal, a reptile vet is the authority.
The short version
- Breed only healthy adults: females at least 18 months old and over 350 g, ideally 2 years old [18][24].
- Females lay clutches of about 15–35 eggs, 4–6 weeks after mating, and can lay several clutches a season [18][23].
- Incubate at 82–86°F (28–30°C) [27] and never above 88°F (31°C), where sex reversal starts to appear [31].
- High incubation temperatures turn genetic males into females. No temperature produces extra males [29][31].
- Rest females after 2–3 clutches, and line up homes for the babies before you pair.
This chapter assumes your dragons already have the setup in the Housing chapter: correct UVB, a basking surface around 105°F (40.5°C), a 77–88°F (25–31°C) gradient, and a calcium-rich diet [18].
Sexing
Bearded dragons have no external genitals you can see at rest. Sexing relies on indirect signs, and it gets more reliable with age.
| Method | What to look for | Reliability |
|---|---|---|
| Hemipenal bulges | Gently lift the tail toward the back (never force it). Males show two bulges on either side of the vent with a groove between them; females show one central, softer bulge or none | The best home method. Workable from about 4–6 months; experienced keepers sometimes call it at 4–8 weeks, but mistakes are common that young [19] |
| Flashlight | Same handling; in a dim room, shine a small light through the base of the tail from above. Two dark shadows mean male; one central shadow means female | Same as above; easier on pale or hypo dragons [19] |
| Femoral pores | A row of pores under each thigh. Males' pores are larger, waxier and more obvious | Not reliable until adulthood, because the pores do not fully develop before maturity [19] |
| Head, beard and behavior | Males tend to have broader heads, darker beards and bob more | Least accurate; females also bob, puff and hiss [19] |
A good rule: treat sex as "probable" under six months, and "confirmed" only on adults or after a reptile vet checks. For certainty, wait until about one year [19].
Why are hatchlings so hard to sex? Genetically female embryos, including temperature-reversed ones, grow hemipenes in the egg and then lose them before hatching [20]. This is also why there is no DNA sex test for this species (see Temperature and Sex below) [21].
Maturity: when is a dragon old enough?
Bearded dragons can physically breed far earlier than they should. Females raised fast in production facilities have bred at 5–6 months [22]. That is the worst case, not a goal.
We recommend these minimums:
- Female: at least 18 months old and over 350 g (12.3 oz), whichever comes later. Dr. Margaret Wissman, DVM, sets the floor at 18 months or 350 g [18]; we ask for both. Ideal is two years and a healthy adult weight of roughly 350–500 g (12.3–17.6 oz) [23]. Dr. Luqman Javed, DVM, recommends adults "ideally at least 2 years old" [24].
- Male: at least 12–18 months; normal maturity is about 12–15 months [22]. Pair him with a female of equal size or weight [18] so he does not injure her during the neck-bite.
- Both: vet-checked, with blood work and repeated adenovirus swabs (one test can miss it) [24], parasite-screened, and at a steady weight for the three months before pairing.
Why the weight floor matters: building eggshells pulls calcium from the female's bones. Under-conditioned females lay smaller clutches and run a higher risk of egg binding (dystocia) and a calcium crash after laying [23]. Dystocia is described as the most common reproductive disease in captive female lizards, and poor nutrition, wrong temperatures and an unsuitable nest site are leading causes [25].
Brumation (winter cycling)
Bearded dragons sometimes breed without a cool period, but fertility and timing are better with one [18]. Cycle only healthy adults at target weight. Never cool a thin dragon or one with a known illness.
| Step | Setting |
|---|---|
| Lead-in | Stop feeding 7–10 days before cooling so the gut empties; keep water available (keeper experience, not proven) |
| Daytime | Roughly 73–80°F (23–27°C) basking, down from the normal 105°F (40.5°C) [22][24] |
| Night | 59–68°F (15–20°C) [22][24] |
| Light | About 10 hours light, 14 hours dark [22][24] |
| Length | 2–3 months is the common advice [18][24]; Dr. Wissman accepts as little as 2–4 weeks [18]. Breeders often cool for about two months [22] |
| Warm-up | Return to normal temperatures and light, then resume feeding. Spreading this over about a week is keeper experience, not proven. Breeding behavior usually starts 3–4 weeks after warm-up [22] |
Sources differ by a few degrees on brumation temperatures; the table shows where they overlap.
Weigh monthly during brumation. If a dragon loses more than about 10% of its weight, warm it up and have it seen (keeper experience, not proven).
Pairing and courtship
Introduce the male into the female's enclosure, or use a neutral breeding enclosure. Courtship is fast and physical.
- Male: his beard darkens to black, and he bobs his head rapidly, stomps his front feet and chases. He bites the base of the female's neck to hold her while mating [18][24].
- Female: head-bobbing and arm-waving signal she is receptive [24]. A female that runs, flattens and bites back is not ready. Separate them and try again in a few days.
A workable schedule: pair for one week, separate for one week, repeat, then one final week together [18]. Once you have seen several matings, separate them for good and move the female to her own enclosure with a lay box [18].
Watch every pairing session. Neck bites can tear skin, and the risk is higher with mismatched sizes or with silkback females (see the Genetics and Morphs chapter).
Mated females can store sperm for up to about 12 months, so a female may lay fertile clutches long after separation [23].
Gravid signs and the lay box
Eggs are usually laid 4–6 weeks after successful mating [18][24]. Signs include:
- A visibly fuller, very enlarged belly [24]. Late on, keepers often say the eggs look or feel like a bag of marbles.
- Appetite falls, often to nothing in the last week [18].
- Restlessness, pacing the corners and digging at the floor [18][24].
The lay box: a plastic tub or a 10–15 gallon tank, set inside or in place of the enclosure. Fill it with about 8 in (20 cm) of moist, reptile-safe topsoil or a topsoil and sand mix, damp enough to hold a tunnel [24]. Set it under a warm spot and tilt it slightly so she can dig a burrow [18]. Give her privacy. A female that will not settle can hold her eggs.
Red flags, same-day reptile vet: visibly gravid for more than 4–5 weeks without laying, digging for 24–48 hours with no eggs, straining, growing lethargy, or hind-leg weakness [23]. Low blood calcium can stop the oviduct from pushing eggs out [25]; tremors or twitching after laying are also a reason to call the vet. Egg binding in reptiles is rarely sudden and can drag on for weeks. Medical treatment often fails, and surgery is common [26].
Clutch size and clutches per season
| Figure | Range | Source |
|---|---|---|
| Eggs per clutch | 15–35 typical; 20–25 most common for a healthy adult | [23] |
| Eggs per clutch | About 25 average; 15–20 low, 45–50 high | [24] |
| Eggs per clutch | 20–30 average; German Giant-line females can exceed 50 | [22] |
| Clutches per season | 2–5, roughly 4–6 weeks apart | [23] |
| Clutches over a lifetime | About 3 in the first 18 months; up to 7 in a female's second full season; 3–4 in the third year; declining after 2–3 years and often finished by about age 7 | [22] |
Treat 7 clutches as what a female can do, not what she should do. We recommend capping a female at 2–3 clutches per season and giving her a full year off after any season in which she lost condition (breeder experience, not proven).
Females lay infertile ("slug") clutches with or without a male, and clutch size is about the same either way, so the calcium and energy cost is similar [23].
Egg handling
- Collect eggs within a day of laying. Lift each egg without rotating it, and mark the top with a soft pencil. Eggs should not be turned during incubation [27].
- Fertile eggs are white, firm and plump. Yellowish, shriveled or see-through eggs are usually infertile. When in doubt, incubate anyway and remove them later. Candling (shining a light through the egg) shows a pink blush and blood vessels in fertile eggs after about a week (breeder experience, not proven).
- Set eggs on their sides, spaced so they do not touch. Breeders either half bury them [22] or lay them in shallow pockets without covering them [24].
- Check eggs daily. Remove any that collapse, discolor or grow mold; one rotting egg can spoil its neighbors [27].
- Dented eggs usually mean the medium is drying out. Add water to the corners of the tub, never onto the eggs [22].
Incubation
| Setting | Target |
|---|---|
| Medium | Vermiculite (perlite is acceptable), mixed about 1:1 with water by weight, filling the tub about half full [22][24] |
| Humidity | Around 80% inside the egg box [24][27] |
| Temperature | 82–86°F (28–30°C), with 83–84°F (28.3–28.9°C) a good target [27]. A breeder reference gives 81.5–85°F (27.5–29.5°C) [22]; Dr. Javed gives 84–85°F (29°C) [24]. Do not go above 88°F (31°C) [31] |
| Time to hatch | Usually about 60 days; 40–90 days is the full range quoted [27]. Warmer runs shorter. One breeder reference gives 45–55 days at 81.5–85°F (27.5–29.5°C) [22]; Dr. Javed gives 60–70 days at 84–85°F (29°C) [24]. In the lab, eggs at 82.4°F (28°C) hatched at about 73 days and eggs at 96.8°F (36°C) at about 47 days [20][28] |
| Incubator room | Keep the incubator in a room cooler than the set point, so the thermostat only has to heat [24] |
Eggs "sweat" about 24 hours before hatching and collapse slightly about 12 hours before [22]. Hatchlings slit the shell with an egg tooth and may sit half-out for hours. Leave them alone [22].
Leave the first hatchlings in the incubator for about a day; their movement seems to prompt their siblings to hatch [24][27]. Eggs still unhatched 72 hours after the first one pips are very unlikely to hatch [24].
Temperature and sex: what the science says
The bearded dragon is a textbook case of a mixed sex-determination system, and it matters for anyone incubating eggs.
- Bearded dragons have sex chromosomes. ZZ animals are male and ZW animals are female [29].
- High incubation temperatures override the chromosomes, and ZZ embryos develop as fully functional females. Quinn and colleagues first showed this in the lab in 2007, and Holleley and colleagues (2015) found sex-reversed ZZ females in the wild: 11 of 131 animals sampled, mostly from the warmer north of the range [29][30][31].
- The effect increases with temperature. Reversal is rare at 87.8°F (31°C), rises as temperature climbs, and approaches 100% female at 96.8°F (36°C). Researchers treat about 89.6°F (32°C) as the threshold [31].
- No incubation temperature produces extra males. Cool incubation does not turn ZW females into males; it simply gives the genetic ratio, roughly 50:50 [29][30].
- Sex-reversed ZZ females are fertile, and in lab matings they were more fecund than ZW females [29]. Bred to a normal ZZ male, they produce only ZZ offspring, and those offspring are themselves more prone to reverse [30].
What this means for your incubator:
- Keep the whole incubation under 88°F (31°C). Anything above that risks a female-heavy clutch, and above about 90°F (32°C) breeders report embryo deaths [22].
- You cannot "cook for males." Claims that cooler eggs give more males are not supported by the research [29][30].
- A clutch that hatches mostly female after an incubator overshoot may contain ZZ females. They look and breed like females, but they will skew the sex ratio of their own babies. One behavior study found they act more like genetic males in boldness, activity and basking; treat that as a single lab study [32]. Note any overshoot on your breeding records.
Hatchling care and first feeds
- Move hatchlings to a rearing tub once they are active and fully out of the egg [22][24].
- Rear in small groups sorted by size, with the larger, stronger babies apart from the smaller ones [24]. Big babies out-compete small ones for food and may nip toes and tail tips (keeper experience, not proven).
- Use the same lighting and heat as adults: strong UVB and a basking surface around 105°F (40.5°C), with a cool end in the high 70s°F (about 25–26°C).
- Offer the first feed about 2–3 days after hatching, once the yolk is absorbed: small gut-loaded crickets and chopped vegetables [24]. The usual rule is insects no longer than the space between the eyes, offered 2–3 times a day, with finely chopped greens from the start so they learn to eat vegetables (keeper experience, not proven).
- Mist or give a shallow, supervised soak daily for the first few weeks, in lukewarm water no deeper than the hatchling's elbows; hatchlings dehydrate quickly (breeder experience, not proven).
- Weigh weekly. A hatchling that has not eaten by day 7, or is losing weight after day 10, needs a check.
When babies are ready for new homes
Hatchlings are generally ready for new homes at 6–8 weeks [27]. We also wait until they are eating insects and greens reliably and have gained weight steadily for at least two weeks. Many breeders also use a size floor of about 6 in (15 cm) total length or 10–15 g (breeder experience, not proven). A baby should be seen eating for at least a week before it goes home. The longer babies stay, the better the sexing call you can give the new owner.
How many babies to expect
Realistic yearly numbers for one healthy adult female:
| Plan | Clutches | Eggs | Hatch rate | Hatchlings |
|---|---|---|---|---|
| Conservative (recommended) | 2 | 40–50 | 70–80% | 30–40 |
| Typical hobby | 3 | 60–75 | 70–80% | 45–60 |
| Maximum reported | Up to 7 [22] | 150+ | Varies | 100+ |
Clutch sizes come from [22][23][24]. The hatch rate is breeder experience, not proven, and no peer-reviewed source gives one. One or two females can produce far more babies than most people can place, so line up homes before you pair [22].
Breeding responsibly
Bearded dragons are among the most surrendered reptiles. They are easy to breed, they lay large clutches, and the babies are small enough to buy on impulse.
Every clutch costs the female bone calcium and body condition. Egg binding and follicular stasis are captive diseases that are rarely seen in the wild and are tied to husbandry stress [25].
We recommend:
- Breed only for babies you can house, feed and place as well-started juveniles.
- Rest females after two or three clutches.
- Retire females around age 5–6, before 7, when egg production has usually ended anyway [22].
- Never produce silkbacks (two leatherback copies), and never breed dragons with known neurological or skeletal problems. See the Genetics and Morphs chapter.