Australia has around species of land snake, and 32 recorded species of sea snakes. Some Australian snakes are venomous, although only 12 are likely to inflict a wound that could kill you. The most dangerous snakes belong to the front-fanged group, which in NSW include the tiger snake, brown snake, death adder, mulga or king brown snake and a few species of sea snake.
Australia's other snakes are the solid-toothed non-venomous snakes such as pythons, blind snakes and file snakes and venomous rear-fanged snakes such as the brown tree snake and mangrove snakes. Snakes are not naturally aggressive and always prefer to retreat. They will only attack humans if hurt or provoked and most bites occur when people try to kill or capture snakes. If you come across a snake in the bush, just calmly walk the other way.
If you find a snake in your home or garden and would like it removed, contact your nearest snake catcher on the reptile handler list. Eleven species of sea snake and one species of sea krait have been recorded in NSW waters. Most of the sea snakes recorded from NSW are seen very infrequently and are vagrant individuals that have strayed from their core tropical populations.
The exception is the yellow-bellied sea snake Pelamis platurus which is considered abundant and is probably a long-term resident in the oceanic waters off the NSW coast. In the marine environment, sea snakes occupy a range of habitats from muddy turbid estuarine waters to clear waters of coral reefs.
Most species live in warm tropical or subtropical waters. Snakes have no eyelids and cannot close their eyes. Their eyes are protected by a clear scale which is part of their skin and functions like spectacles. Many snakes have excellent eyesight, particularly some of the daytime predators such as whip snakes , and most have good eyesight at least over short distances.
However, in most snakes the sense of smell is more vital. A snake's main organ of smell is its forked tongue, which it flicks in and out of its mouth. The tongue picks up scent particles from the air and any objects it touches, and transfers them to two depressions in the roof of the mouth. These depressions are unique to reptiles and detect scents transferred to them from the tongue. A snake's nostrils are only used for breathing. Snakes do not have outer ears - instead they hear with inner ears, which pick up vibrations from the ground through the head and belly scales.
Some nocturnal snakes, such as pythons, also have heat sensory pits to help them locate the 'warm' birds and animals they prey on. Not having legs, snakes use waves of muscle contractions along their bodies to move. Movement is helped by the belly scales, which catch on any uneven surface. If the ground is very smooth, snakes find it difficult to move in any direction at all. Tree-living snakes, such as pythons, 'shuffle' along horizontal branches in muscular waves which pass along their bodies.
Most snakes are good swimmers, and sea snakes have paddle-shaped tails which give them added propulsion in the water. A snake sheds its skin between one and four times a year. It does this by rubbing the front of its head on a rough surface until the skin splits. The snake then slowly sloughs out of the skin, turning it inside out as it does so. In all snakes, the new skin with the same colours and patterns as the old is underneath and, when shed, the old skin is almost transparent.
When a snake is about to slough, the scale forming the spectacle over its eye will become 'milky', affecting its vision. Snakes are reptiles, which means they are ectothermic: they get their body heat from external sources. Endothermic animals, such as mammals and birds, regulate their body temperature internally. A snake's body temperature - and so its level of activity - is controlled by the temperature of the air and the ground.
It will try to maximise body heat by basking in the sun or lying on or near warm surfaces such as night-time roads or even, on occasion, household water heaters. In cold areas of the state snakes hibernate during winter. However, in the more temperate climate along the coast they shelter in rock crevices and logs during cold weather and come out on warm days to soak up the heat of the sun. During cold weather snakes are less active and therefore hunt less.
In the winter their metabolisms slow down, and they use up body fat which has been stored up during the warmer months of the year. Catching and feeding is a very specialised activity. Most venomous snakes grab their prey by striking suddenly and biting while they inject venom into the victim.
Some species will often strike three or four times. The toxins produced by the venomous snakes act to paralyse the victim, so that it dies or is unable to move before the snake tries to eat it.
These toxins also assist the snake's digestive processes, beginning by breaking down the victim's blood and other tissues. While the term poisonous and venomous are often used interchangeably, they mean quite different things. Read more: Why are some snakes so venomous? Venom is a specialised type of poison that has evolved for a specific purpose.
For venom to work, it needs a wound to enter the body and into the bloodstream. Snakes, therefore, are generally venomous, not poisonous. But there are exceptions. For example, the American garter snake preys on the rough-skinned newt which contains a powerful toxin.
Remarkably, these snakes can also assess whether a given newt is too toxic for them to handle , and so will avoid it. Based on the median lethal dose — the standard measurement for how deadly a toxin is — the Australian inland taipan is ranked number one in the world. Several other Australian snakes feature in the top But does that make them the deadliest? Death by snake bite in Australia is very uncommon, with just two per year , on average, compared to 81,, deaths from snakes annually worldwide.
Read more: Yes, Australian snakes will definitely kill you — if you're a mouse. A lack of access to antivenoms and health care contribute substantially to deaths from snake bites. Fast-moving, aggressive and known for their bad temper, eastern brown snakes, together with other browns are responsible for more deaths every year in Australia than any other group of snakes.
Not only is their venom ranked as the second most toxic of any land snake in the world based on tests on mice , they thrive in populated areas, particularly on farms in rural areas with mice. Its venom causes progressive paralysis and stops the blood from clotting, which may take many doses of antivenom to reverse. Victims may collapse within a few minutes. Also known as: gwardar Found: widespread over most of mainland Australia — absent only from the wetter fringes of eastern Australia and south-western Western Australia.
Said to be less aggressive than its eastern cousin, the western brown snake is still highly dangerous and part of the group of snakes that causes the most fatalities in Australia. Western browns tend to be fast moving and nervous in temperament. When disturbed, they will run for cover, striking quickly if cornered, then making a quick getaway. Bites are usually painless and difficult to see due to the small fang marks. Victims will experience headache, nausea, abdominal pain, severe coagulopathy blood clotting disorder and sometimes kidney damage.
Also known as : common tiger snake Found : along the south-eastern coast of Australia, from New South Wales and Victoria to Tasmania and the far corner of South Australia. Mainland tiger snakes are responsible for the second-highest number of bites in Australia, as they inhabit highly populated areas along the east coast, including some metropolitan areas of Melbourne.
They are attracted to farms and outer suburban houses, where they hunt mice nocturnally and can easily be trodden on by unsuspecting victims in the darkness. Bites are fatal if untreated, causing pain in the feet and neck, tingling, numbness and sweating, followed by breathing difficulties and paralysis.
The venom also damages the blood and muscles, leading to renal failure. Adult snakes are usually but not always banded, with ragged stripes varying in colour from pale yellow to black along a solid, muscular body that can grow to 2m.
When threatened, they flatten their necks and strike low to the ground. Also known as : fierce snake or small-scaled snake Found : in cracks and crevices in dry rocky plains where the Queensland, South Australia, New South Wales and Northern Territory borders converge.
Reclusive and rare, the inland taipan hides out in its remote, rocky habitat. This snake only makes the top 10 because of its highly toxic venom, considered to be the most potent of any land snake in the world; it has the potential to kill an adult human within 45 minutes. Hunting in the confined space of the burrows of the long-haired rat, the inland taipan uses its potent venom to finish off prey quickly, injecting more than 40, times the amount needed to kill a g rat.
The prey has little chance of fighting back. Only a handful of people all snake handlers have been bitten by this species. Each survived with first aid and hospitalisation. Also known as: eastern taipan Found : in an arc along the east coast from northern New South Wales to Brisbane and northern Western Australia. They are fond of sugarcane fields. Coastal taipans are equipped with the longest fangs of any Australian snake 13mm , and have the third most toxic venom of any land snakes.
Before the introduction of a specialised antivenom in , taipan bites were nearly always fatal and caused many human deaths. The venom affects the nervous system and the blood, with nausea, convulsions, internal bleeding, destruction of the muscles and kidney damage. In severe cases, death can occur in just 30 minutes.
Packed full of interesting and useful facts, this handy reference will help you to appreciate and avoid these often misunderstood animals.
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