The frilled-neck lizard is instantly recognizable due to the large fold of paper thin skin which they expand around the head when threatened. At all other times the frill is held flat against the neck.
Their head is large and angular coming to a point at the nose. The body ends with a long, tapered tail.
Their colour is variable being grey, black and yellowish or reddish brown. This has darker mottling which form large blotches. The underside is white or yellow. In mature males it is often black. Their pattern is a useful adaptation allowing them to camouflage on tree branches.
They measure 70-90cm (27.5-35.5in) long and weigh 500-800g (17.5-28oz). Males are typically larger than females.
To hunt they will sit on a tree branch and then once they spot prey in the distance they will run down the tree to catch the prey item.
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Australia, Indonesia and Papua New Guinea are the native homes of the frilled-neck lizard. In Australia they can be found in the north of the country throughout Queensland and the Northern Territory. In Papua New Guinea and Indonesia they live in the south of the island of New Guinea.
They make their home in forests and woodlands. Most of their time is spent in the trees.
Mating takes place at the beginning of the wet season around September to October with the eggs being laid from November to February.
During the breeding season the male frilled-neck lizard will maintain a territory and they become incredible aggressive to other males.
Males will perform a courtship display for the female and if she is interested in mating she will bob her head in response.
Following a successful mating the female will dig a nest in sandy soil. This is typically 10-20cm (4-7.9in) deep. In to this nest the female will deposit a clutch of eggs with the average amount being 8-14. Some clutches have numbered up to 23 eggs though. In seasons where resources are abundant then they can produce 2 clutches of eggs. The eggs have a soft shell.
The eggs incubate in the nest for 70 days. Once they hatch they will emerge from the nest and are independent from birth.
Hatchlings have more pronounced patterning at birth. This is their sole defense as the frill is poorly developed at birth. Their gender is determined by the temperature at which they incubate. When incubating between 29 and 35oC (84-95oF) both sexes will hatch. At temperatures on either side of this range then all females are produced.
Sexual maturity is reached at 1 ½ years old.
The frilled-neck lizard spends most of their time in the trees. Once they complete their threat display they will often climb a tree to escape the predator.
When they run the frilled-neck lizard may stand solely on its two back legs.
During the day they will bask in the sun to regulate their temperature. Their frill may also be expanded to provide additional surface area where they can absorb heat from the sun.
Predators and Threats
The predators of the frilled-neck lizard include raptors, quolls, dingoes, large pythons and monitor lizards. They are also threatened by invasive species such as feral cats which prey on them and cane toads which may poison them if they attempt to eat it.
When threatened their primary defense is to raise the frill and stand on their back legs. They will open the mouth and then begin to hiss. Typically this display is enough to make predators leave them alone.
Climate change may pose a threat to the future populations of the frill necked lizard due to their breeding behavior. At higher temperatures only females will hatch and this could disrupt the population’s gender balance.
Humans further affect their population through hunting for the pet trade and habitat destruction.They have come under threat from the increase in fire activity in the areas where they live.
They are the largest member of the agamid (dragon) lizard family within Australia.
Another name for this lizard is the frilled dragon or frilled necked lizard.
Kelly McCarthy from Chattanooga, TN / CC BY-SA (https://creativecommons.org/licenses/by-sa/2.0)
Used under license
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