iHerp Australia Issue 7 | Page 8

clutches always have a selection of yellowish to orange- coloured neonates. If raised indoors without natural levels of ultraviolet (UV) light, these snakes become progressively paler and more yellowish, and the darker markings with higher melanin levels fade and become more indistinct over time. While some of these snakes can look spectacular I would not class them as natural, and they represent a potentially-unpleasant trap for inexperienced keepers. If these snakes are moved into outdoor enclosures (common practice amongst Tasmanian keepers) they can get horribly sunburnt in a single day in mid-summer. This may seem very odd to some that a snake could get sunburnt, but if a captive-raised snake whose skin and scales have never been exposed to UV light is suddenly exposed to high levels, the results can be catastrophic. Sunburnt pale snakes can turn melanotic within a very short time as the skin tries to adapt to UV. I have seen this phenomenon on many occasions and always urge keepers to exercise extreme caution when introducing indoor-raised snakes to outdoor enclosures. I always do this in August when day lengths are still relatively short, mid-day temperatures comparatively low and solar angle is low in the sky. This gives the snakes’ skin a chance to adjust gradually and burns are avoided. In this way, snakes that were always going to be pale will remain so and those that would naturally have darkened up do so in a natural manner. Sunburnt snakes typically display a rather ugly and unnatural-looking solid dark grey to black streak which runs the entire length of the body, particularly along the spine which is exposed to the most direct sunlight. If you are offered a golden tiger, it is a good idea to learn as much as you can about its parentage and captive history to determine if you have the genuine article or simply ‘fool’s gold’! Further Reading For more pictures of colour and other variations in Tasmanian tiger snakes see: Fearn, S. 1993. The tiger snake Notechis scutatus (Serpentes: Elapidae) in Tasmania. Herpetofauna 1988: 3 -4. Fearn, S. 2011. A rich and varied canvas: Scale variations and scarring on Tasmanian tiger snakes Notechis scutatus (Serpentes: Elapidae). The Tasmanian Naturalist 136: 2-18. Fearn, S. 2014. Snakes of Tasmania. Queen Victoria Museum and Art Gallery. Launceston. Below: the pale snake was born to a wild-caught female from Bruny Island, southern Tasmania. I had to be very careful when introducing this specimen to natural sunlight outside to avoid sunburn. Photo by S. Fearn.