Meet Queensland’s most dangerous animals
Issued: 13 Feb 14 minutes read

Queensland is Australia's most biodiverse state. In amongst the koalas and kangaroos are some of nature’s deadliest animals. Learn more about them.

Welcome to Queensland, Australia’s most biodiverse state. We’re home to 70% of Australia's mammals, 80% of its native birds, and more than half of its reptiles, frogs, and plants.

Across our landscape you will find koalas, kangaroos and countless other cuddly critters. However, amongst them live some of nature’s deadliest residents.

From the stealthy saltwater crocodile patrolling our northern waterways, to the world's most venomous snake, the inland taipan, slithering around our arid west.

Many of Australia’s most dangerous animals call Queensland home. Let’s take a closer look at them (from a safe distance).

    In the water

    Blue-ringed octopus hunting at night

    Blue-ringed octopus

    Despite growing to just 12cm in size, the venom harboured by a single blue-ringed octopus is potent enough to kill 26 humans. Found in tide pools and shallow reefs across the Indo-Pacific, these creatures blend into their surroundings until provoked. When feeling stressed, its blue rings intensify in colour. This signals a warning – leave me alone.

    If you see one of these incredible animals in the wild, keep a respectful distance and never pick one up. While blue-ringed octopus bites are rare, their venom is about 1200 times more toxic than cyanide to humans and there’s no known antidote.

    If you don't already know, you’d better learn how to treat a bite or sting from a venomous animal.

    Australian box jellyfish

    You would think an animal with 3m tentacles would be easy to see in shallow waters. But in coastal northern Australia, the transparent box jellyfish often goes unnoticed. In their search for prey, they swim towards movement, and on hot, calm days, much like humans, can be found in shallow water around creeks, rivers, and even boat ramps.

    Australian box jellyfish venom also happens to be among the deadliest in the world. It is the most rapidly acting venom known to science and can kill a person in under 5 minutes. They house their venom in nematocysts, which are located throughout their tentacles. These harpoon-like spikes serve as their primary tool for hunting prey such as small fish and crustaceans. When these tentacles sting a human, it can be deadly. At least 70 fatal box jellyfish stings have been recorded throughout Australia since 1880.

    If you plan on swimming at the beach up north, never enter the water when a beach is closed. Always swim on patrolled beaches, and if provided, within stinger nets. Also, consider wearing clothing or a stinger suit to cover your exposed skin. The more skin you cover, the better protection you have.

    Underwater image of bull shark in the blue ocean

    Bull shark

    Infamous for its aggressiveness and size, the bull shark is one of the world’s most intimidating animals. While humans are not usually on its menu, bites do occur. Bull sharks, along with white sharks and tiger sharks, are responsible for most of Australia’s shark bites and fatal shark attacks.

    What makes these sharks unique is their ability to spend extended periods in freshwater. Despite most sharks only able to survive in the ocean, bull sharks have adapted to cross over into rivers. Females sometimes give birth in river mouths, where their young can stick around for up to 5 years.

    As apex predators, sharks play an important role in the ecosystem by maintaining the species below them in the food chain. They help remove the weak, the sick, and keep balance between competitors, which helps species diversity.

    A textile cone shell on sand at night

    Cone shells

    Of the 500-600 species of cone shells found throughout the world, 133 of them live in the waters of the Great Barrier Reef. These pretty-looking shells may appear harmless, but housed in them is a venomous snail wielding a harpoon-like tooth that it shoots at prey. The most venomous of the species, Conus geographus, is capable of killing a person within 1-5 hours, and is responsible for over 30 fatalities worldwide.

    Fortunately, cone shells are not aggressive to humans, and it is unlikely swimmers or snorkelers will find them in shallow waters. Stings usually occur when divers handle them in deep reef waters. In Australia, cone shells are typically found in tropical regions from north Western Australia to southern Queensland. You should never pick one up, under any circumstances.

    Here is how to treat a cone shell bite.

    Irukandji jellyfish

    Next to the box jellyfish, which can weigh up to 6kg, the Irukandji jellyfish is a speck. Its bell only grows to around 2.5cm in width – about that of a $2 coin. Irukandji become dangerous to humans when they get swept inshore by winds and currents, especially in summer. Their sting causes Irukandji syndrome, which is characterised by severe pain, muscle cramping, hypertension, and potentially life-threatening cardiac complications.

    Scientific knowledge of the Irukandji only began in 1964, when it was determined a jellyfish is what caused Irukandji syndrome, a mysterious toxin discovered near Cairns 12 years prior.

    Much about these tiny jellyfish is still a mystery. What we know now is there are up to 20 jellyfish species that can cause Irukandji syndrome with their stings. Who knows how many more will be discovered?

    Underwater image of bull shark in the blue ocean

    Saltwater crocodile

    The largest of all living reptiles and an iconic Australian animal, the saltwater crocodile is one of the only animals that sees humans as prey. Adults usually reach about 3 to 5 metres, with males typically growing much larger than females. These apex predators have hardly evolved over the last 200 million years because there has been no pressure to - they are so efficient at what they do.

    In Australia, saltwater crocodiles are found in northern coastal areas in a wide range of habitats, including drainages, rivers, estuaries, creeks, swamps, lagoons and billabongs. They have even been spotted in water twice as salty as the sea!

    No waterway in Croc Country can ever be considered crocodile free. They can be found in both freshwater and saltwater locations hundreds of kilometres inland. If you’re in Croc Country you need to take extra precautions if you decide to go fishing, camping or swimming.

    The best ways you can reduce your risk are to:

    • Stay at least 5m from the water's edge.
    • Dispose of food and fish scraps in a bin or take them home.
    • Keep pets on a lead and away from the water’s edge.
    • Avoid using small watercrafts like kayaks and paddleboards.
    • Stay clear of crocodile traps. You can learn more about crocodile behaviours and specific Be crocwise actions to follow by visiting our website.
    A stonefish swimming around a coral reef


    The stonefish is a camouflage master. It lies still for hours at a time until it blends into its surroundings, becoming virtually invisible. When unsuspecting prey gets close, the stonefish snaps it up in milliseconds. Stonefish primarily live above the tropic of Capricorn, throughout much of the Great Barrier Reef, but have been recorded as far south as Coffs Harbour. They can also survive out of water for up to 24 hours!

    Humans occasionally step on or touch these animals, mistaking them for an encrusted rock or lump of coral. After all, it only grows to about 30cm. This is a problem because the stonefish happens to be the world's most venomous fish. Its 13 needle-like spines running along the dorsal fin on its back prick up when it feels disturbed or threatened. This highly toxic venom, if injected, can kill an adult within an hour.

    Fortunately, no stonefish deaths have been recorded in Australia since European arrival. An antivenom was also developed in 1959, reducing this likelihood even further. Still, knowing how to treat a sting doesn’t hurt.

    A tiger shark swimming near an ocean bed with a fish alongside it

    Tiger shark

    Out of all the shark species in Australia, the tiger shark is proportionally responsible for the most fatalities of all shark species. It is the world’s second largest predatory shark, growing to at least 6m in length, and is capable of digesting almost anything. These opportunistic scavengers eat whatever they can, including fish, turtles, seabirds, jellyfish, crustaceans, sea snakes, and other sharks.

    Sometimes, tiger sharks even eat indigestible objects. In the past, they have been found with trash, even license plates, inside their stomachs. Their carefree diet is the reason why tiger sharks are sometimes referred to as the ‘garbage cans of the sea’. These powerful fish are found worldwide in tropical and subtropical waters. In Queensland, they have us surrounded!

    If visiting one of our wonderful beaches, you can be SharkSmart every time you are on or in the water with these steps:

    • follow signage and swim between the flags at patrolled beaches
    • have a buddy and look out for each other
    • don’t swim at dawn or dusk
    • always swim in clear water
    • avoid schools of bait fish or diving birds
    • keep fish waste and food scraps out of the water where people swim.

    On land

    Close-up of a coastal taipan uncoiling itself, moving over leaves

    Coastal taipan

    Armed with the lengthiest fangs among Australian snakes, the coastal taipan is the world's third most venomous land snake. They are also Australia’s longest venomous snake, reaching an average length of 2.5m. Prior to the development of a specialised antivenom in 1956, coastal taipan bites were claimed to be 100% fatal.

    Coastal taipans occupy a wide range of habitats from northeastern New South Wales, up through Queensland, and across to northern Western Australia. They are usually active during the day but also can be at night during hot weather. They mainly feed on small mammals such as rats and mice in eucalypt woodland, grassland, grassy beach dunes, pastures, and cane fields.

    Humans encounter coastal taipans most commonly in sheds, farm buildings and waste heaps. While they are not a naturally aggressive snake, they are highly strung, and if surprised or cornered will defend themselves.

    Living around snakes is more common than not throughout Australia. That’s why you should know how to make your house/property snake-safe. You should also know how to treat a snake bite.

    If you encounter a snake, don't panic. Back away to a safe distance and allow the snake to move away. Snakes often want to escape when disturbed, and when left alone, they present little or no danger to people.

    If you find an injured snake on your property, be sure to contact a licensed contractor who can remove it safely.

    If hiking, always stay on formed paths or tracks so that you can see and avoid snakes, wear protective clothing like covered shoes and trousers, and carry a first-aid kit that contains pressure bandages.

    A death slithering over foliage of leaves

    Death adder

    The common death adder is an ambush predator that sits motionless, concealed in leaf litter, sand or gravel, twitching the worm-like lure on the end of its tail to attract prey. They are found throughout Australia in forests and woodlands, grasslands and heath.

    Unlike other snakes that flee from approaching humans, death adders are more likely to sit tight, and risk being stepped on, making them dangerous to the unwary bushwalker. They tend to be reluctant to bite unless touched.

    To minimise your risk of encountering a snake when hiking, you should:

    • always stay on formed paths or tracks so that you can see and avoid snakes
    • carry a first aid kit that contains pressure bandages with you
    • always wear protective clothing such as covered shoes and trousers
    • carry a torch at night so that you can see where you are going.
    Eastern Brown Snake

    Eastern Brown snake

    Reaching an average length of 1.5m, this medium-sized snake holds a grim title: In Australia, it (along with other brown snakes) is responsible for more deaths every year than any other snake group. Eastern browns are found over all but the western-most parts of Queensland. They can cope and even thrive in places of human disturbance, like farmland, and since their natural habitat range includes some of the country’s most populated regions, this species is likely more encountered with than any other snake.

    Eastern brown snake venom ranks as the world's second-most potent among land snakes. They are fast-moving and sun-loving, generally active during the day, especially when the weather is hot. They are often found around houses and sheds in search for prey like rats, mice and lizards. Being an alert, nervous species, eastern browns often react defensively if surprised or cornered, putting on a fierce display and striking with little hesitation.

    A jet black funnel-web spider on rock

    Funnel-web spider

    There are about 40 species of funnel-web spiders in Australia, and despite the most well-known one, the Sydney funnel-web spider, not being in Queensland, there are still plenty of others that you need to be cautious around.

    The northern tree funnel-web spider and its smaller counterpart, the southern tree funnel-web spider, stand among the most perilous. Around half of their bites lead to severe reactions.

    Annually, funnel-web spiders bite around 30-40 individuals, yet the availability of antivenom has proven highly successful. Their diet spans from beetles to frogs, and these spiders tend to be more active during the warmer months, typically between November and March.

    A highly venomous inland taipan curled up on the ground

    Inland taipan

    The world’s most venomous snake. In a single bite, the inland taipan produces enough venom to kill 250,000 mice. As notorious as this snake’s venom makes it, the inland taipan doesn’t exactly ‘live up to the hype’. Compared to its coastal cousin, the inland taipan is shy, and many reptile keepers regard it as placid to handle. There is not a single recorded human fatality to its credit. This may be in part because of how rare they are to encounter in the wild.

    Inland taipans are found in Queensland’s desolate west, where our border meets South Australia and the Northern Territory. Usually, they are only above-ground for a short period during the early morning. For the rest of the day, since their habitat hardly contains any cover or vegetation, they retire to deep cracks and fissures formed in the dry soil to escape the heat and hunt its preferred prey, the long-haired rat.

    Dangerous poisonous native Australian redback spider climbing through a garden in a local backyard

    Red back spider

    Redback spiders are found all over Australia. They hang out in dry, cozy spots like garden sheds, mailboxes, even under toilet seats. Females are about 1cm long with a red stripe on their back. They are also the only ones with a dangerous bite. Their venom messes with the nervous system, but their tiny fangs make many bites ineffective.

    Around 2000 redback spider bites get reported each year, with roughly 250 people getting antivenom. Thankfully, no deaths have occurred since the creation of the spider's antivenom back in the 1950s.

    A southern cassowary walks through the forest

    Southern Cassowary

    The southern cassowary is an imposing creature. It can stand up to 2m tall and possesses dagger-like claws which can grow to 12cm. It also happens to be Australia’s heaviest bird, weighing up to 76kg. These large, flightless birds are found in far north Queensland’s tropical rainforests, where they play an important role in maintaining the diversity of rainforest trees.

    Southern cassowaries are the only frugivore (fruit eater) that can disperse large-seeded rainforest fruits over long distances. They swallow fruits whole, digesting the pulp and passing the seeds unharmed in large piles of dung. These droppings, laden with hundreds if not thousands of seeds, act as natural fertilizer. Some rainforest seeds even require the cassowary's digestive process to germinate.

    Unfortunately, a combination of habitat loss, vehicle strikes, and domestic dog attacks have caused only about 4000 southern cassowaries to remain in Queensland. A recovery plan for the southern cassowary has been created to combat its ‘Endangered’ status.

    Be wary around these birds. Southern cassowary behaviour is unpredictable. They can inflict serious injuries to people and pets by kicking with their large, clawed feet. They should never be approached or fed. If you come face-to-face with a cassowary, back away slowly and put something (like a tree or backpack) between yourself and the bird, and let it go on its way.