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By Anders Nielsen, Ph.d.
Tiger snakes got their name because they are usually banded with their belly lighter than the rest of their body. They are fairly large (6 feet) and live in Australia and islands around Australia, such as Tasmania. The fact that there are isolated populations (Tasmania is 150 miles from the mainland) and the coast shore of Australia is almost endless gives rise to a number of local variations of tiger snakes—some of which are considered sub-species.
The tiger snake is perhaps most infamous because of its highly potent venom. A way to estimate the toxicity of different venoms is to compare their LD50-values. The LD50-value tells which concentration of the venom was sufficient to kill 50 percent of a mice population. For the tiger snake, this value is 0.214 mg/kg (value from www.seanthomas.net). The value is sub-cutaneous, which corresponds to the venom being injected during a bite.
One must keep in mind that not all snakes are capable of injecting the same amount of venom. Larger snakes will not only be able to deliver a higher dose of venom, their fangs will also penetrate human skin. The tiger snake being a fairly large and strong snake, this should not be a problem.
Antivenin exists against its venom, but if it is not administered in time, the chances of dying from paralysis are high.
One would think that these snakes are so dangerous that no one would dare to collect them and subject them to experiments.
However, this is not the case. Tiger snakes are often collected by biologists and herpetologists, and it is not only to extract its venom to find out if it can be used for medical purposes.
One example is a recent study (Aubret et al., 2007, in AMPHIBIA-REPTILIA), where a group of Australian scientists found out that the foraging behavior of tiger snakes was related to how hungry they were. They collected a number of young tiger snakes, and raised them on two types of diets: one diet with lots of food and one diet with only enough food to sustain themselves. The snakes were then subjected to conditions where they were at risk of being eaten. These special conditions got the tiger snakes raised on a low diet to take more chances during their foraging than their well-fed companions.
This phenomenon is known as "predation risk-associated foraging." This study was about to find out if that is present within the Notechis scutatus genus.
Aubret F. et al Food versus risk: foraging decision in young Tiger snakes, Notechis scutatus AMPHIBIA-REPTILIA 28(2) pp 304-308 (2007)
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