- The Perentie is the largest of the Goannas, and one of the largest monitors in the world. They have spotted skin and five fingers and toes with claws.
- Goannas differ from all other lizards in having a forked tongue like a snake which they constantly flick in and out.It picks up scents from the air and transfers them to a structure called the Jacobsons organ, on the roof of the mouth, where they are interpreted.
- They are ectothermic which means they raise their temperature by basking in the sun. Perenties eat almost anything they can overpower including other reptiles, birds, mammals and carrion. They are significant predators to the introduced rabbit and house mouse. Their teeth are thin, sharp and backward curving like snakes. They’re designed for holding prey not chewing. Mouthfuls are swallowed whole, with a characteristic jerking motion: literally thrown down the throat.
- Perenties shelter in burrows or beneath rocky outcrops and boulders. In the mornings they can move to the entrance of their shelter, and place their head out in the sun for warmth. Because the head receives the greatest blood supply, the Perentie can raise its temperature to an acceptable level without exposing itself to too much danger. However when it cools right down in winter (May-August), they are usually inactive, remaining in their shelter.
- When threatened, Perenties raise their bodies, distend their throats with air, and exhale noisily making a loud hissing sound. They can also cause injury to the intruder by whipping it with their very strong tail, and by biting or scratching with their large teeth and claws.
- Goannas are among the world’s oldest lizard families and are thought to be highly intelligent.