Blotched blue-tongued lizard
The Blotched Blue-tongued Lizard (Tiliqua nigrolutea) is a skink with a fleshy blue tongue which is used to taste the air and scare off potential predators. They are a robust and relatively large member of the skink family (Scincidae) that tend to rely on camouflage and bluff as their primary means of defence. However, if cornered or molested they put on an impressive and effective defensive display. If further molested they will bite, but mainly as a last resort and although their bite is painful due to their powerful jaws, their teeth are blunt and generally don't break the skin. They are of course harmless like all skinks and are inoffensive by nature, often being kept as pets due to their appealing, inquisitive natures and readiness to become tame.
The lizard is about 35 to 50 cm long and is found in wet and dry sclerophyll forests, montane woodland and coastal heathlands. It is an omnivore with a diet consisting of leaves, flowers, fruit, slow-moving invertebrates, and small vertebrates. The tail can also be dropped (autotomy) when grasped by a predator (like most skinks) but these large skinks are much less likely to do so.
They are found in south-eastern parts of Australia including Tasmania and the islands of Bass Strait. In the northern parts of their range like the central tablelands of N.S.W, they are restricted to highland areas, whereas in southern Victoria and Tasmania they can be found right down to the coast. Some herpetologists believe that there are two distinct forms of this species - a highland or alpine form and a lowland or southern form. Specimens from the northern parts of the species range (alpine form) are generally larger, blacker and tend to have more colourful blotches on their back, which are sometimes pale pink, salmon-pink or orange in colour.
Blotched Blue-tongued lizards emerge from brumation in early spring, which is the mating season. These large skinks are viviparous (give birth to live young) with the highland/alpine form giving birth to relatively larger and fewer babies, compared to the lowland form. The young are usually born in autumn, after a relatively long gestation period. They are relatively long-lived (anecdotally 20 years or more) compared to many of the small skink species. They have adapted well to some rural and urban areas, where they can be found living on farms and in gardens, where they are an asset, as they love to eat pests like snails, slugs and occasionally rodents.
- Cogger H, (2000) Reptiles & Amphibians of Australia.
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