goanna) Mertens' water monitor – V. mertensi Spiny-tailed monitor – V. acanthurus (also ridge-tailed monitor) Mangrove monitor – V. semiremex Black-headed monitor – V. tristis Short-tailed monitor – V. brevicauda Argus monitor – V. panoptes (also yellow-spotted monitor) Rosenberg's monitor – V. rosenbergi Spencer's goanna – V. spenceri Storr's monitor – V. storri Dampier Peninsula monitor – V. sparnus Mitchell's water monitor – V. mitchelli Kings' monitor – V. kingorum Southern Pilbara rock goanna – V. hamersleyensis Black-palmed rock monitor – V. glebopalma Kimberley rock monitor – V. glauerti Pygmy mulga monitor – V. gilleni Rusty desert monitor – V. eremius Stripe-tailed goanna – V. caudolineatus Pilbara monitor – V. bushi Black-spotted ridge-tailed monitor – V. baritji Emerald tree monitor – V. prasinus Canopy goanna – V. keithhornei Habitats Goannas are found throughout most of Australia, except for Tasmania, and manage to persist in a variety of environments. Most species are known to climb trees or outcrops; several primarily arboreal species are known. The lace monitor (V. varius) is probably the best-known among these, but is not the most common. The lace monitor is the second-largest of all goannas, reaching lengths up to . Other more common tree goannas, such as the Timor tree monitor (V. timorensis) and mournful tree monitor (V. tristis,) do not grow to quite such lengths, typically a maximum of 61 cm, nose-to-tail. Other goannas are adapted to swampy coastal environments, such as the mangrove goanna (V. semiremex). Further still, Mertens' water monitor (water goanna – V. mertensi), found in lagoons and rivers across northern Australia, is streamlined for swimming, using its tail as a paddle. Most other goannas are good swimmers, but tend not to voluntarily venture into water. Diet The diets of goannas vary greatly depending on the species and the habitat. Prey can include all manner of small animals: insects, smaller lizards, snakes, mammals, birds, and eggs. Meals are often eaten whole, thus the size of their meals may depend on the size of the animals. Many of the small species feed mostly on insects, with some being small lizard experts. Many of the medium to large species feed on whatever prey they can catch. This includes eggs, fish (V. mertensi), birds, snails, smaller lizards, snakes, marsupials, and other small mammals, such as rodents. The giant perentie has been observed killing a young kangaroo, and then biting out chunks of flesh like a