The tiger snake is a usually timid species which, like most snakes, usually retreats at the approach of a human. They are an interesting snake which despite the name may not have any striping at all.
The Tasmanian tiger Snake has recently been shown to be the the same species as that which occurs on the south-eastern Australian mainland, (Notechis scutatus). The markings are extremely variable and should not be used in isolation to identify snakes. Colours range from jet black, through yellow/orange with grey bands to sandy grey with no bands. There are unconfirmed reports of red-bellied tiger snakes in north-east Tasmania. Typical forms are of a black snake with either no bands or faint yellow to cream bands. Dark olive snakes with yellow bands are fairly common.
Generally the belly is pale yellow, white or grey, the enlarged ventral scales often edged with black. The head is broad and blunt. It can be difficult to distinguish the tiger Snake from the copperhead since sizes, habitat preferences and behaviour overlap somewhat. Tiger snakes have 13 - 19 rows of scales around the middle of the body, the usual number being 17. On the mainland of Tasmania, tiger snakes reach a length of 1 to 1.8 m. The Chappell Island population reaches prodigious lengths -- up to 2.1 m. Male tiger snakes reach a greater size than females and have larger heads.
Wide ranging from dry rocky areas, woodlands, to wet marshes and grasslands. Tiger snakes occur in most habitats in Tasmania. They become inactive over winter, retreating into rodent burrows, hollow logs and tree stumps. Groups of as many as 26 juvenile snakes have been found overwintering in the same place. Generally, tiger snakes do not stay in the same place for more than 15 days, males being especially prone to wandering.
Tiger snakes feed mainly on mammals and birds under 300 g in weight. Tiger snakes habitually raid birds nests and have been found climbing trees to a height of 8 m. A good indicator of the presence of a Tiger snake is the alarm calls of small birds such as honeyeaters and thornbills. They also eat other vertebrates including lizards, smaller snakes, frogs and occasionally fish. Juvenile tiger snakes will use constriction to subdue struggling skinks, a principal food of smaller snakes. Adult snakes are also known to use constriction on larger prey as well. Tiger snakes are important predators of introduced rodent pests and readily enter the burrows of mice, rats and even rabbits in search of their quarry. On a number of offshore islands juvenile tiger snakes feed on small lizards, then as they approach maturity the diet switches to muttonbird chicks. Because these resources are limited competition is fierce and the chances of these snakes reaching adulthood is less than one percent. Occasionally tiger snakes will eat carrion.
A slow, careful hunter which may stand its ground if surprised, relying on its impressive threat display for defence. Like most snakes, tiger snakes are first cowards, then bluffers, and only become warriors as a last resort. If threatened a tiger snake will flatten out its neck, raising its head to make itself appear as frightening as possible. If the threat persists, the snake will often feign a strike, producing an explosive hiss or 'bark' at the same time. Like most snakes, tiger snakes will not bite unless provoked.
Sexual actvity is sporadic throughout summer and reaches a peak in late January and February. Mating may last for up to 7 hours, the female occasionally dragging the male about. Males don't eat during periods of sexual activity. Females stop eating 3-4 weeks before giving birth. Female litter sizes have been recorded as high as 126 young, and litter size is often related to female body size. Tiger snakes from small islands produce fewer, larger young. Baby tiger snakes when born are 215 - 270 mm in length. Females produce young at best every second year. There is no maternal care amongst Tiger snakes. Tiger snakes do not become more aggressive during the breeding season, but a male snake tracking a female may well have his mind on other things and may be more easily surprised or be in an unfamiliar environment. He may consequently be more nervous if disturbed.
Found in most habitats throughout Tasmania and on may of the offshore islands. As well as being found in southeastern mainland Australia tiger snakes have been recorded from the following Islands: Babel Is., Cat Is., Chalky Is., Christmas Is., Flinders Is., Forsyth Is., Great Dog Is., Hunter Is., King Is., Little Green Is., Maria Is., Mount Chappell Is., New Year Is., Seal Rks, and Trefoil Island.
Secure, although some Island populations may decline if offshore activities threaten muttonbird colonies.
Now legally protected in Tasmania, tiger snakes still face great danger from human activities such as destruction and fragmentation of habitat. Many are needlessly killed on the road when deliberately run over.
Fangs and poison
The highly toxic venom is produced in large amounts. The venom is mainly neurotoxic, affecting the central nervous system, but also causes muscle damage and affects blood clotting. The breakdown of muscle tissue can lead to kidney failure.