Читать книгу The Bearded Dragon Manual - Philippe De Vosjoil - Страница 4

1: GENERAL INFORMATION

“Bearded dragon” is the common name applied to lizards of the genus Pogona in the family Agamidae, several of which display a beard-like extension of the throat, which turns black when threatened. The bearded dragon most readily available to pet owners is the inland bearded dragon (P. vitticeps). Because the inland bearded dragon is by far the most popular, the information presented in this book relates to that species unless indicated otherwise.

Two other types of bearded dragon are commercially bred in very small numbers: Lawson’s dragon (P. henrylawsoni) and the Eastern bearded dragon (P. barbata). Lawson’s dragon is a smaller and naturally tame species, but, unfortunately, it does not reproduce as easily as the inland bearded dragon and thus is not readily available. The large Eastern bearded dragon is rarely offered for sale because it also has proven difficult to breed consistently and presents certain problems in long-term husbandry that still need to be resolved. Hybrids between inland bearded dragons and Lawson’s dragons are occasionally offered for sale under the name Vittikin dragons.

Inland bearded dragons now come in a variety of morphs, including normal brown-and-tan dragons, although true “normals” are difficult to find. There are colors such as Citrus and Super Citrus, Fire Red, and Hypo Orange (Tangerine); pale hypomelanistic pastels (Hypo Pastels); and even “white” types, including Hypo Ice, Snow, and some Zero dragons. New patterns, such as the Dunner and exciting Purple Paradox, have emerged. Translucent dragons are on the scene; in our line, they have black eyes. Another interesting variety is the leatherback bearded dragon, which displays reduced tubercles on the skin, making it smoother to the touch. We can continue to expect to see new morphs in the future because breeders constantly strive to introduce variety into the hobby.

Prices for inland bearded dragons vary considerably, depending on the individual’s sex, color morph, genetics, health, age, and expected reproductive rate. You will have to evaluate which of the various kinds of bearded dragon is best suited for your purpose, whether you are looking for a pet, a living work of art, or a source of revenue from breeding. The next step is to find a high-quality source for your new bearded dragon. Bearded dragons are available through breeders’ websites, at pet shops, and at reptile shows.

Bearded dragons are easy for children to handle if done properly.

Is a Bearded Dragon the Right Pet for You?

As mentioned, many experts rank the bearded dragon as one of the very best reptile pets. These lizards are beautiful, active, entertaining, moderately sized, easy to handle, naturally tame (with few exceptions), and relatively easy to keep. Compared to smaller reptiles, they are robust and hardy. Compared to larger reptiles, they are relatively safe for children, although basic hygiene habits such as hand-washing must be practiced. The only potential downside that we’ve found is their enclosure requirements. As adults, these lizards require an enclosure of at least 48 inches long (longer if you have the space).

Because bearded dragons require substantial amounts of food, including live insects, they defecate frequently, so their enclosures and substrates have to be cleaned daily. Of course, there are ways to minimize the amount of time that cleanup takes. Using paper towels as a substrate makes cleanup fast and easy, but some owners may prefer the look of reptile carpet. Either way, we find that our customers spend about 10–15 minutes a day caring for their bearded dragons.

Although bearded dragons seem to present less risk of disease transmission than some other reptiles, you must practice simple hygiene if you are to share your home with a bearded dragon. Any reptile can carry the Salmonella bacterium, which can be shed in the feces and may pose a disease threat to humans, especially infants, toddlers, and those who are immune suppressed. You should never allow your bearded dragon on food-handling surfaces, such as kitchen counters and dining-room tables. You should wash your hands immediately after handling your bearded dragon. Wash your dragon’s food and water bowls separately from your household dishes. And, of course, keep your bearded dragon’s enclosure scrupulously clean. Sound judgment and common sense will keep your dragon a low-risk, valued member of the household.

An Eastern bearded dragon.

Natural Habitat

All bearded dragons originated in Australia. Although dragons currently found in the pet trade are many generations removed from their Australian roots, details about their habitat in the wild provide clues to proper husbandry in captivity.

Most bearded dragons live in relatively hot, arid regions of Australia, and thus require a warm, dry enclosure in captivity. However, water is mandatory and should be offered in shoulder-deep water bowls, through misting and/or soaking (depending on the age of the animal), and through fresh greens. A bearded dragon’s enclosure should offer temperature gradients, meaning that the dragon should be able to move from the hot basking side of the tank to the cool side to lower its internal temperature when necessary.

Wild bearded dragons in Australia enjoy climbing and basking on rock piles and on the rails and posts of fences. When designing a home for your juvenile dragon, include a long, low, smooth rock—natural or artificial. For an adult, a large, thick piece of driftwood will act as a climbing branch and be happily accepted. Provide a basking light so the dragon can heat up, which stimulates feeding.

A proper bearded dragon setup recreates certain aspects of its wild habitat.

Longevity

Although there are a few reports of pet inland bearded dragons exceeding ten years of age, most live between five and eight years if they are initially healthy and raised in good conditions. One of our customers called us to report that her dragon died at the age of twelve, so she obviously was an excellent caregiver. She acquired the supplies that we recommended, and she followed the care instructions that we gave her when she first purchased the dragon. She called us when she had questions rather than relying on the opinions of other pet owners.

It is easy to fall in love with bearded dragons, but loving a bearded dragon is not enough when it comes to giving your pet the care he needs and deserves. Being an excellent caregiver is what will give your dragon the potential to reach his maximum life expectancy. The fact that you purchased this book says that you are well on your way to understanding your bearded dragon’s needs and providing an environment that meets those needs.

Bearded dragons of all ages, from baby (shown) to adult, need an adequate supply of clean water to prevent dehydration.

Sexing

Accurately determining the sex of baby bearded dragons is difficult; at best, it is an educated guess. Adults, however, show secondary sexual characteristics that allow for relatively easy sexual identification.

When trying to sex juvenile bearded dragons, people often examine several factors. The first trait to look at is the tail taper. The tails of females taper more sharply from the base compared to those of males, which appear just slightly thicker. In our experience, this method is most successful when applied to the small percentage of individuals that show greater extremes of tail taper. The differences in tail taper often become more pronounced as bearded dragons grow older.

The femoral pores are examined next. Prominent femoral pores on a 6-inch juvenile would indicate a probable male. Femoral pores show as a running line of dots on the inner thighs of the dragons.

Head size is also possibly helpful in determining the sex of babies because males tend to have a wider skull base compared to females. This is not always true but, combined with the aforementioned methods, looking at the skull’s width can help you determine the probable sex of a baby bearded dragon.

Another technique has improved the accuracy of sexing small bearded dragons, but it must be performed with extreme care and is best done by an expert dragon handler. This method consists of holding a 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 sexual maturity as early as five to six months of age. The growth rate begins to taper off after about six months.

Our studies show that baby bearded dragons kept under conservative husbandry conditions can increase in size a mind-boggling 4,000 percent within six months of hatching. Under more intensive conditions, a 5,000-percent increase in weight may occur. A baby inland bearded dragon will weigh about 0.08 ounces (2½ grams) at birth. By four months of age and a length of 12 inches, it will weigh about 4 ounces (between 100 and 125 grams—just imagine a human baby growing from 7 pounds to 280 pounds in four months!). Most Super Citrus dragons will reach 16 inches by six months of age if maintained under optimal conditions.

What’s the lesson to be learned from this? Kept in optimal conditions, bearded dragons can grow fast, requiring more food than you may have realized and larger enclosures at an earlier age than you may have planned. Of course, the upside to this fast growth is that within a very short period of time, your bearded dragon can be sitting on your shoulder and becoming more involved with the family group.

Common Health Problems

As with many fast-growing lizards, the most common problem seen in immature bearded dragons is calcium deficiency associated with soft bones (metabolic bone disease or MBD) or with twitches and seizures (low blood calcium or hypocalcemia). Calcium deficiency results from several factors that may occur singly or together: improper vitamin/mineral supplementation; inadequate heat, which prevents the absorption of calcium supplements; an inappropriate diet or feeding schedule; and insufficient exposure to an ultraviolet-B (UVB) light source. Prevention is simple: follow the instructions in this book.

Two other diseases common in bearded dragons of all ages are caused by parasites. One is heavy pinworm infestation, which remains a significant cause of these lizards’ failure to gain or maintain weight. Another, more problematic, disease is coccidiosis, caused by a type of protozoan parasite. Both diseases require diagnosis and treatment by a qualified veterinarian (see Chapter 10).

Older pet dragons may suffer from gout, liver disease, kidney failure, or even cancer. The current knowledge about these disorders suggests that ensuring proper hydration, correct thermal gradients, and an appropriate balanced diet are the best potential preventive measures.