​Date Published: February 2012
Assessment Summary
The Perentie (Varanus giganteus) is the largest lizard in Australia and the fourth largest lizard in the world. It is widespread throughout the arid to semi-arid interior of Australia from the coast of Western Australia to central Queensland. There is also a population on Barrow Island, off the coast of northern Western Australia. Perenties occur on open sand plains and on sand ridges.
They are mostly ground dwelling, occupying rocky outcrops and deep crevices. Perenties also forage widely in sandy desert and claypans and will sometimes climb trees when disturbed. The lizards on Barrow Island are active throughout the year.
Perenties feed on insects, reptiles, birds, small mammals and carrion. Large adults can predate on small kangaroos. They are opportunistic cannibals and will feed on live and dead conspecifics. On Barrow Island Perenties eat turtle eggs and hatchlings. Although data is limited, Varanus giganteus probably breed in spring or early summer. It is likely that females only have one clutch per year, with an average clutch size of 9.3 eggs. Most varanids lay their eggs in a hole dug in the ground, or at the end of a burrow.
Perenties are protected in all jurisdictions where they are present in Australia. Varanus giganteus is not listed on the IUCN Red List of Threatened Species. The species is a 'controlled animal' under the Tasmanian Nature Conservation Act 2002.
The Perentie is not considered a pest species. It has not established feral populations outside its native range. There is no evidence of the species having any major impacts on the environment or agriculture.
There is a low likelihood that this species could establish in Tasmania, with potential for minor impacts. The most significant impact is likely to be predation because Perenties have a broad diet and could potentially prey on a variety of native animals. The assessment concludes that these impacts are only likely to be low, largely because the Tasmanian climate is not suitable for the species.
This risk assessment categorises Perenties as a moderate threat to Tasmania and proposes that imports be restricted to those licence holders approved for keeping moderate threat species.
Assessment Documentation
Perentie (Varanus giganteus) (806Kb)