The frilled dragon was a creature of legend to budding American herpetologists growing up in the 60’s and 70’s – we devoured what little published information existed, but seeing one alive was out of the question, short of a trip to its habitat. It is still hard for me to imagine that, as a Bronx Zoo reptile keeper, I acquired my first 2 individuals a mere 15 or so years ago (at $1,500 each!). Today these magnificent lizards are commercially bred in large numbers – both on “farms” in Indonesia and by herptoculturists worldwide.
Although not an “easy” species, and certainly one requiring a good deal of space, frilled dragons are among the most rewarding lizards to keep, and will provide you with a lifetime of interest and enjoyment. This week we’ll take a look at their natural history, so that we can better understand how to provide for these fascinating animals in captivity.
The body color ranges from grayish through orange-brown to nearly black, often with dark variegations along the sides, and usually matches the color of local tree trunks. The inner surface of the frill (the large skin fold about the neck) is shaded in yellow, black, orange and/or red. The hind legs are powerfully built. Males can reach 38 inches in length; females are somewhat smaller.
The neck frill is supported by cartilaginous rods and is connected to muscles in the tongue and jaw. It expands when the lizard gapes its jaws and is used to intimidate predators and rivals, and in courtship displays. Frilled dragons are one of the few lizards to use bipedal locomotion – they flee predators by rising up and running off on their rear legs.
Range and Habitat
Frilled dragons are found in northern Australia and southern New Guinea. They frequent open tropical and warm temperate forest and wooded scrub land.
Largely arboreal, they dwell in the forest canopy during the dry season. During this period the lizards reduce their food and water consumption, metabolic rate and body temperature. The rainy season is largely spent on tree trunks within 4-15 feet of the ground.
In northern Australia and other parts of the range, frilled lizard habitat is subjected to frequent fires (natural and human induced, as a component of habitat management) during the dry season. Field research has revealed that the lizards escape the fires by re-locating to the highest branches of large Eucalyptus trees. Interestingly, it was also found that a number of individuals descend to the ground and shelter in abandoned termite nests during fires – a most unusual (and, it would seem, learned) behavior for an arboreal lizard.
Status in the Wild
Populations appear stable; protected by the Australian government.
Caterpillars, scorpions, ants, termites, beetles, spiders and other invertebrates, small lizards and snakes; nestling birds and small mammals are taken on rare occasions.
Frilled dragons seem to occupy a unique feeding niche within a lizard-rich habitat. Although largely arboreal, they feed on the ground by dropping from their tree-trunk perches to intercept passing insects and small animals.
Research has shown that, immediately after dry season fires, the percentage of large invertebrates in the frilled dragons’ diets increases significantly. It seems that the lizards are able to see larger prey animals more easily once the ground cover has been burned off. So strong is this effect that lizards living in unburned areas move into the burned areas as soon as the fires have subsided.
Males are highly territorial and fight for breeding rights. Both sexes use neck frill displays during courtship and territorial disputes. Mating coincides with the start of the rainy season. Females bury 8-14 eggs in the ground, and may produce 2 clutches each year if food is plentiful. The eggs hatch in approximately 69 days and the young average 2 inches in length. Hatchlings stay in close proximity to each other, possibly as a defense mechanism, for approximately 10 days.
Frilled Dragon Relatives
Frilled dragons are classified within the family Agamidae, which contains over 300 species. Some of its members are among the most common and typical lizards of their habitats, while others have extremely specialized diets, unique adaptations and very restricted ranges. Most hunt beetles, spiders, scorpions and a wide variety of other invertebrates, but the dabb lizards, Uromastyx spp., of North Africa and the Middle East are herbivorous (in captivity they are especially fond of dried split peas!) while Australia’s thorny devil, Moloch horridus, subsists entirely upon ants.
The toad-headed lizards, Phrynocephalus spp. and the pygmy lizards, Cophotis spp. are unique among the Agamids in bearing live young. Toad-headed lizards inhabit the deserts of south and central Asia, and utilize microscopic channels among their scales to funnel dew to the mouth. Southeast Asia’s slow-moving pygmy lizards, likened by some to chameleons, have prehensile tails and dwell in high-altitude moss forests.
Perhaps the most commonly-seen of Africa’s lizards are various species of the genus Agama (commonly known as “agamas”), males of which perch on fences and houses and bob their brightly-colored (often blue) heads in courtship displays. As with most Agamids, their head and body coloration intensifies during the breeding season. Equally conspicuous throughout much of India and Southeast Asia are the various Calotes species, often locally referred to as “garden lizards” due to their propensity to take up residence near people. Australia’s bearded dragon, Pagona vitticeps, is a popular pet, with millions bred yearly by hobbyists to supply the trade.
Among the more unusual Agamids are the 40 or so species of Draco, the “flying lizards”. These supremely adapted aerialists are the only lizards to have developed elongated ribs to assist in gliding (flying geckos, Ptychozoon spp., also glide, but utilize small skin flaps along their sides). The flying lizard’s ribs are covered by loose-fitting, brightly colored skin (the patagium) that, when extended, allows for “flights” of at least 50 feet and for considerable in-air maneuverability. Other unique family members include the cold-tolerant Himalayan agama, A. himalayana, which ranges to 11,000 feet above sea level, and the horned agamas, Ceratophora spp., males of which sport a long, flexible appendage on the tip of their snouts.
We still have a lot to learn about the spectacular frilled dragons – please observe yours closely, and pass along your ideas and questions. I’ll be sure to include them in future articles.
Excellent summaries of two frilled dragon field studies are posted at: