Overview
Dendrelaphis punctulatus, also known commonly as the Australian tree snake, the common tree snake, and the green tree snake, is a species of slender, large-eyed, diurnal, non-venomous snake in the family Colubridae. The species is native to many parts of Australia, especially in the northern and eastern coastal areas, and to Papua New Guinea. It is an agile snake with a very slender body and tail and is also a strong swimmer, using the water for hunting and avoiding predation. The ventral body colour varies from golden yellow, to bright green, to olive-green, to black, sometimes even blue, while its back is typically dark in colour. It is frequently pale yellow on the throat and belly, but other pale colours have been noted. Blue flecks are present on the flanks. The eyes are large, with typically golden-coloured irises and large round pupils.
It is found in a variety of habitats ranging from rainforest to woodland to urban areas where it preys on fish, frogs, and other small animals. It is a non-venomous species and does not constrict its prey, but rather relies on its sharp, angled teeth to 'chew' its prey down the oesophagus.
Description
A study of D. punctulatus in Queensland showed females having an average snout–vent length of with males slightly shorter at . Studies show that the snake may attain a total length in females of in females,
Distribution and habitat
D. punctulatus is common in Australia's northern tropics and eastern Australia. It is also found from the Kimberley region (Western Australia) to Cape York and Torres Strait (Queensland), extending down the east coast into New South Wales, and north into Papua New Guinea. It can be found at altitudes from sea level to .
Behaviour
When D. punctulatus is near water it often looks for long grass, blending in to hide while watching for its prey to come to nearby rocks or banks to bask or play. It will also enter house gardens that have fountains or ponds surrounded by long grass or shrubs. It is active during the day, and rests at night in hollow trees, logs, foliage, or rock crevices. It is often found resting in trees; hence the name "tree snake".
Feeding
Frogs, water skinks, and small reptiles and their eggs form a large part of the common tree snake's diet, but it will also eat small fish, mammals, geckos, and turtle hatchlings.
Reproduction
An oviparous species, the common tree snake lays 5–12 elongated eggs per clutch.
Defensive behaviour
Although D. punctulatus is essentially harmless to humans, it will defend itself by producing an odour from its cloaca, and may bite. Sometimes when approached, the snake inflates its body and neck to make itself seem larger, a tactic sometimes used to scare predators. Generally, however, the green tree snake in the wild will make a quick escape when it feels threatened.
Gallery
Common Tree Snake f9 3618 02.jpg Common tree snake, a blue variation, Cairns, Queensland Common Tree Snake f9 3618 01.jpg Common tree snake, a blue variation, Cairns, Queensland Common tree snake (Dendrelaphis punctulatus) Daintree 5.jpg Common tree snake (Dendrelaphis punctulatus) Daintree 2.jpg Common tree snake (Dendrelaphis punctulatus) Daintree.jpg Green Tree Snake eating White-lipped Tree Frog.JPG Green tree snake eating white-lipped tree frog near Cooktown, Queensland
Further reading
*Cogger HG (2014). Reptiles and Amphibians of Australia, Seventh Edition. Clayton, Victoria, Australia: CSIRO Publishing. xxx + 1,033 pp. . *Fearn S, Trembath DF (2010). "Natural history of the common tree snake, Dendrelaphis punctulatus (Serpentes: Colubridae), in the wet–dry tropics of north Queensland". Australian Journal of Zoology 58 (6): 384–389. *Gray JE (1827). "Reptilia". Appendix. pp. 424–434. In: King PP (1826). Narrative of a Survey of the Intertropical and Western Coasts of Australia Performed between the Years 1818 and 1822. With an Appendix, Containing Various Subjects Relating to Hydrography and Natural History. Volume II. London: John Murray. viii + 637 pp. + Plates A–C + Errata. (Leptophis punctulatus, new species, pp. 432–433). (in English and Latin). *van Rooijen J, Vogel G, Somaweera R (2015).
"A revised taxonomy of the Australo-Papuan species of the colubrid genus Dendrelaphis (Serpentes: Colubridae)". Salamandra 51 (1): 33–56. (Dendrelaphis punctulatus, pp. 50–51, Figure 11A). *Wilson S, Swan G (2013). A Complete Guide to Reptiles of Australia, Fourth Edition. Sydney: New Holland Publishers. 522 pp. .
External links
*Common or Green Tree Snake video *Wild herps *Environmental Protection Agency