Reptile & Amphibian Forums

My beardie juts laid eggs one month ago and now looks like she is about to lay another and is digging again. I knew they could lay 2 clutches a year but can they do it that close together?

Oh,my,they can lay FAR more than 2 clutches....most of mine lay 5-6. I had a female lay 8 fertile and one infertile back to back [ I've never heard of that in 16 years] and she was not with a male after her 5th clutch was laid. They do retain sperm and can lay several clutches even after just one breeding.So it is perfectly natural...as a matter of fact I've never had a female lay only one clutch. Just feed her AS MUCH as she wants to eat,with calcium dusting at least 2-3 times a week.

They dont retain sperm. Sperm dont lay dormant inside the dragon and wait to fertilize them at a latter date.

When they breed the sperm start a cycle of egg laying. Some wil undergo several cycles yes.

But they do not retain sperm, this is a myth.

*not trying to sound like a know it all* Just an FYI

It's just a way of saying it...without the male fertilization a female would lay all inferts.,but once he has mated with her she can continue to lay eggs that are fertile without further mating...but this doesn't happen in all cases. I love a good " know it all" ...makes for interesting conversation. [ just kidding]

awesome thanks a lot. I knew they could retain sperm (as a lot of reptiles can, even if they usually dont) but I though the time between clutches would be a longer. On the retaining sperm thing I had a gecko lay eggs a few weeks ago that hasnt been with a male since I breed her last summer. And they are fertile. I know that was a little off topic but kinda cool.

Sperm do not have the ability or life span that lasts all that long. I believe they live in the neighborhood of 24 hours.

Once the female reptile (some species will differ) but once the internal cycling of her reproductive organs is turned on she can go into a dormitory state and not lay eggs right away. In other words... She could post pone possibly to a latter date to go into labor. Or as in the case of the bearded dragon it initiates a cycle of eggs produced.

I believe her eggs are impregnated with the males DNA and then the males DNA information is stored.

The females do not store sperm though. It is more complicated than that.

It's a good topic for further investigation.

I think thats kinda what we were saying just without knowing the correct scientific details. I realize the actual sperm isnt still in her, but somehow the info stays so she could later produce fertile eggs without mating again. Good to point that out though, it would be interesting to know in more detail how that happens.

I stand corrected...

Im still digging but according to some articles reptiles do retain sperm... they have special storage areas that essentially nourish and retain the sperm for use at later periods.

A very unique adaptation.

This is an article on sea turtles but I assume a similar situation is occurring with dragons.

See here:

Reproductive ducts of male and female soft-shelled turtles, Trionyx sinensis were examined throughout the year (March, May, September, December) using brightfield and electron microscopes (TEM and SEM), to determine the location and histomorphological characteristics of sperm storage structures as well as their changes at different phases of the seasonal reproductive cycle. Sperm stored in the epididymis were also examined. In the male, spermatogenesis is initiated in spring (May), and then the mature sperm are released in autumn as an episodic event. Spermatogenesis is inactive in winter. However, in this species, the epididymis contains sperm throughout the entire year. Sperm observed in the epididymis are intact and some structures are uniquely different from other reptiles, and is characterized by 35–40 concentric mitochondria with a dense core in the centre. Many glycogen granules are observed in the cytoplasm of the midpiece. However, the epithelial cell type of epididymal duct change in different seasons. The cells are fully developed with a highly secretory activity in September. The materials secreted from the epithelium might have the function as nourishment for the stored sperm. Sperm storage structures in the form of tubules are observed in the wall of the isthmus of the oviduct in hibernating females but are absent in the groups of May and September. These tubules develop either by folding or fusion of the oviductal mucosal folds and are lined by both ciliated and secretory cells. These tubules might provide a microenvironment for the sperm to enable its long-term storage. After being separated 4 months (December–March) from the male, sperm are observed in the tubules of the isthmus of the oviduct. The unique character of the sperm combined with the special sperm storage structures enable the sperm to maintain fertility and activity during their storage.

Interesting read on reptile reproduction:

The earliest reptile fossils known are from the Upper Carboniferous period, approximately 270 million years ago, but by this time several of the reptilian orders were already in evidence, including both anapsid cotylosaurs and synapsid pelycosaurs. This finding implies that reptile evolution began much earlier. Another implication is that temporal vacuities (empty spaces) and emarginations (notches), although widely distributed in reptiles, are not defining characteristics of this class of vertebrates, because several groups do not have them. The earliest defining characteristics may never be known unless some very early fossils in good condition are found. It is likely that a desiccation-resistant integument was present. Another area on which to focus is the egg and the reproductive process. The egg is macrolecithal (contains much yolk) and is surrounded by a hard shell in turtles, crocodilians, and geckos and a soft or parchment-like shell in the other squamates. In either case, a shelled egg requires that fertilization occur before shell formation. This means that fertilization must take place within the female's body (i.e., in her oviducts) rather than externally as is typical of fishes and amphibians. Consequently, most male reptiles possess copulatory organs that deposit sperm into the cloaca of the female. From the cloaca the sperm cells migrate up the oviduct guided by chemical stimuli. Male turtles and crocodilians have a single penis homologous to the penis of mammals. This organ develops during embryogenesis from the medial aspect of the embryonic cloaca. Male lizards and snakes have paired hemipenes, which develop during embryogenesis from the right and left lateral aspects of the embryonic cloaca. Some male snakes have bifurcated hemipenes, so the males appear to have four copulatory organs. Thus internal fertilization is the rule among extant reptiles. Even tuatara, the males of which lack copulatory organs, transfer sperm in the manner of most birds with a so-called cloacal kiss involving apposition of male and female cloacae and then forceful expulsion of seminal fluid directly into the female's cloaca. Internal fertilization is necessary because of shell formation around eggs. Many reptiles live far from standing or running water, thus external fertilization in the manner of most fishes or amphibians would be associated with risk of desiccating both sperm and eggs.

The oviducts of some female reptiles are capable of storing sperm in viable condition for months or even years. In some turtles and snakes, fertilization can occur three years after insemination. Theoretically, a female need not mate each year, but she might nevertheless produce young each year using sperm stored from an earlier copulation. Although this interesting possibility has been known from observation of captive reptiles for approximately five decades, we still do not know whether or how often female reptiles use it under natural conditions. Another curiosity of reptile reproduction is that the females of some species of lizards and snakes are capable of reproducing parthenogenetically, even though reproduction in these species normally occurs sexually. (These species should not be confused with others that only reproduce parthenogenetically. This is not a widespread mode of reproduction in reptiles, but it is known to occur in several species of lizards and at least one snake.) Facultative parthenogenesis has only recently been discovered among captive reptiles, and there is as yet no information on whether it occurs in nature.

Macrolecithal eggs allow embryos to complete development within the egg or within the mother in the case of viviparity, such that the neonate is essentially a miniature version of its parents rather than a larva that must complete development during an initial period of posthatching life, as is common among amphibians. The reptilian embryo lies at the top of the large supply of yolk, and cell division does not involve the yolk, which becomes an extra embryonic source of nourishment for the growing embryo. A disk called the vitelline plexus surrounds the embryo and is the source of the three membranes (chorion, amnion, and allantois) that form a soft "shell" within the outer shell of the reptilian egg. Together these structures defend the water balance of the developing embryo and store waste products. Although reptile eggs absorb water from the substrate in which they are deposited, these eggs do not have to be immersed in water as is required for the eggs of most amphibians. Immersion of most reptile eggs results in suffocation of the embryos. Female reptiles deposit their eggs in carefully selected terrestrial sites that provide adequate soil moisture and protect the eggs from extremes of temperature.

Some species have another strategy for protecting embryos from abiotic and biotic exigencies. These reptiles retain the embryos and incubate them within the maternal body. The mother's thermoregulatory and osmoregulatory behaviors contribute to the embryos' welfare and to the mother's welfare. The mother's predator-avoidance behaviors can enhance the fitness of embryos exposed to greater predation elsewhere. In view of these potential advantages, which in some habitats might be considerable, it is not surprising that live-bearing has evolved many times in reptiles, although it is quite rare in amphibians. All crocodilians, turtles, and tuatara are egg layers. At least 19% of lizard species and 20% of snakes are live-bearers. Cladistic studies have shown that viviparity has evolved independently many times within squamates, in at least 45 lineages of lizards and 35 lineages of snakes. It also appears that viviparity is an irreversible trait and that once viviparity evolves, oviparous descendants rarely occur. The term embryo retention is used for species in which females retain embryos until very near the completion of embryogenesis when shells are added. The eggs are deposited and then hatch within 72–96 hours. Examples include the North American smooth green snake Liochlorophis vernalis, and the European sand lizard Lacerta agilis. Most important to understand is that the embryos are lecithinotrophic (nourishment of the embryos comes entirely from the yolk) with no additional postovulatory contribution from the mother. The mother, however, may play a role in gas exchange of the embryos. This process can involve proliferation of maternal capillaries in the vicinity of the embryos, a form of rudimentary placentation. Some species that give birth to live young also have lecithinotrophic embryos that undergo rudimentary placentation. Some embryo-retaining species eventually add a shell to their eggs and oviposit them within a few days of hatching. Others never add a shell, and the young are simply born alive, although they need to extricate themselves from the extraembryonic membranes that surround them. Many herpetologists prefer to abandon the term ovoviviparous because this word connotes that shelled eggs hatch in the maternal oviduct. No species is known in which this occurs. Accordingly, the term viviparous is used for all live-bearers, and herpetologists recognize that considerable variation exists in the degree to which viviparous embryos are matrotrophic (supported by maternal resources through a placenta).

Although females of oviparous species deposit their eggs in sheltered positions, the vagaries of climate can result in relative cooling or heating of oviposition sites with associated changes in moisture. This realization has led to considerable research on the effects of these abiotic factors on embryonic development. It is now known that within the range of 68–90°F (20–32°C), incubation time can vary as much as fivefold, and that neonatal viability is inversely related to incubation time. Hatchlings from rapidly developing embryos at high temperatures perform poorly on tests of speed and endurance relative to hatchlings from slower-developing embryos at lower temperatures. The slower-developing embryos typically give rise to larger hatchlings than do their rapidly developing counterparts. In the context of this work, it was found that the sex ratio of hatchling turtles varied depending on incubation temperature. In several species of tortoise (Gopherus and Testudo), for example, almost all embryos became males at low incubation temperatures (77–86°F [25–30°C]), and most became females between 88°F and 93°F (31–34°C). Temperature-dependent sex determination (TSD) is known to be widespread, occurring in 12 families of turtles, all crocodilians, the tuatara, and in at least three families of lizards. However, the effect of temperature differs in the various groups. Most turtles exhibit the pattern described, whereas most crocodilians and lizards exhibit the opposite pattern, females being produced at low incubation temperatures and males at higher ones. In a few crocodilians, turtles, and lizards females are produced at high and low incubation temperatures and males at intermediate temperatures. It is possible that some viviparous species experience TSD, in which case the thermoregulatory behavior of the mother would determine the sex of the embryos, but this phenomenon has not been observed.

The effect of the discovery of TSD has been enormous. Almost all developmental biologists previously believed that sex in higher vertebrates was genetically determined. This phenomenon has important implications for the management of threatened or endangered populations, especially if the program contains a captive propagation component. Unless care is taken to incubate eggs at a variety of temperatures, the program could end up with a strongly biased sex ratio. Reflection on the effects of global warming on reptiles exhibiting TSD generates the worry that extinction could be brought about from widely skewed sex ratios.

That's ALOT of info to dig up,Dreamworks,thanks for all the hard work.

The time between clutches can range from 2-5 weeks, average is about 3-4 weeks. Healthy female bearded dragons can lay anywhere between 3-6 clutches per season.

Important thing to do is make sure she has a good egg laying spot/bin. You don't want her retaining eggs and possibly risking egg binding or other complications. A good soak after she finishes laying eggs is beneficial, to encourage her to drink, as egg laying is very thirsty work. Also ensure you provide her extra calcium for shell development.

Reptiles do retain sperm, however many mammals will put a pregnancy 'on hold' if conditions are not good at the time. At least rats have this ability. They can mate, become pregnant but arrest emobryol developement for quite some time. I can't remember if its weeks, months or even longer.
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PHLdyPayne

I didnt think this was possible in mammals but my friend who breeds geese on his farm says they can do it also. Retain sperm and hatch out fertilized eggs at a later date.

For birds this would make sense since they are very close to reptiles evolutionary speaking.

Birds are not truly mammals because they lay eggs but they are not considered to be fully reptilian cold blooded either.

There still is alot of speculation about how exactly birds evolved compared to reptiles. Fossils of dinosaurs with feathers have been found but I seem to remember some new fossil was found that added confusion between the link between dinosaurs and early birds.

Either way, some mammals lay eggs (the duck billed platypus and spiny anteater) and many species of reptiles give live birth. There are still alot of differences between birds and reptiles so not good to compare a few traits between them and to say it makes them similar.

The animal kingdom has developed many odd ways to survive, and no matter how much is known, there is always some oddity that goes against everything that was known before.
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PHLdyPayne

It is a very complicated affair (evolution)...

Yes your right though...

Interesting article on the disconnect between birds and dinosaurs:

http://www.sciencedaily.com/releases/2009/06/090609092055.htm

The reptiles that give live birth still lay eggs, they just stay inside the reptile until the young hatch. It was in one of the articles I posted earlier that I read.

No one touched on the time between clutches. I have had dragons lay clutches as close as 15 days apart. But they seem to be more like 19-21 days for most of mine. I think it has a lot to do with availability of resources when it comes to developing subsequent clutches.

Resources?... like food and dragon health?