Brown Tree Snake (Boiga irregularis)

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DESCRIPTION – While Brisbane forms are generally light brownish-orange with variable dark stripes, regional variation produces reddish-orange forms with white stripes. Large head with big eyes. Up to 2 meters length. 19-23 mid-body scales, 225-265 ventral, 85-130 sub ventral, anal single. Family: Colubridae.

DISTRIBUTION – Forest and rainforest, dense shrubland, swamps, mangroves, caves, gorges, and limestone cliffs. Eastern and northern coastal Australia from the Kimberly region in WA to Wollongong, NSW, across into PNG, northwestern Melanesia and eastern Indonesia, with an invasive population established in Guam.

ECOLOGY – Nocturnal. Arboreal, however will forage terrestrially and around water, largely ambushing mammals and birds, occasionally frogs/lizards. Common in urban environments. Oviparous, lays 3-11 eggs.

VENOM – MILDLY VENOMOUS – Some neurotoxic and perhaps myotoxic components, but while bites may cause local pain, swelling, headaches, occasional nausea or even collapse and convulsions, not considered deadly.

Updated November 2019 from Eipper, S. & Eipper, T. (2019) A Naturalists Guide To The Snakes Of Australia. John Beaufoy Publishing.