Australia’s most dangerous wild animals include the box jellyfish, saltwater crocodile, Sydney funnel-web spider, blue-ringed octopus and eastern brown snake. Their venom or strength can kill. But deaths are rare: there is antivenom for many of them, and most keep away from people. A study of 2000 to 2013 found horses killed 74 Australians, more than all venomous animals together.
Dangerous Australian animals quick facts
- Horses killed 74 Australians from 2000 to 2013, more than all venomous animals together.
- Nobody in Australia died from a spider bite between 2000 and 2013.
- The eastern brown snake has caused more snakebite deaths than any other Australian snake.
- The inland taipan has the most toxic snake venom, yet everyone known to be bitten survived.
- Flooding a box jellyfish sting with vinegar for 30 seconds is the first aid.
Australia has some of the most venomous animals on Earth. It also has a surprise. Over 14 years, horses killed more Australians than every venomous animal in the country put together.
Both things are true. This list covers ten animals that really can hurt you in Australia, and then what actually causes the most harm.
1. Box jellyfish
The box jellyfish is almost see-through. Its bell can reach 30 cm across, with up to 60 tentacles trailing up to 3 metres behind it.
It lives in tropical waters from Western Australia to Queensland, mostly in summer. It is one of the most deadly venomous animals in the sea, and a bad sting can be fatal. The first aid is to call 000 and flood the sting with vinegar for at least 30 seconds.
The box jellyfish has a tiny relative that is even harder to spot: the Irukandji jellyfish. Its bell is only 1 to 2 cm across, about the size of a fingernail, but its tentacles can reach 1 metre.
Irukandji live in deeper water off northern Australia, from Western Australia to Queensland. Winds and currents can sweep them close to shore at any time of year, but it happens most often in summer.
The sting may hardly be noticed at first. Then, 20 to 30 minutes later, Irukandji syndrome can start. It brings severe pain in the back, stomach, chest and muscles, a racing heart, and feeling sick, anxious and agitated. In severe cases it can damage the heart, so anyone who thinks they have it needs to go to hospital.
2. Saltwater crocodile
The saltwater crocodile can grow longer than 6 metres. It takes prey as big as a water buffalo, and it has the strongest bite force ever measured in any animal.
It lives in rivers, swamps and the sea across northern Australia. Queensland’s Be Crocwise advice is to stay more than 5 metres back from the water’s edge. Read more about what crocodiles eat.
3. Sydney funnel-web spider
The Sydney funnel-web lives in and around Sydney. The males are the danger. In summer and autumn they wander looking for mates, and they turn up in gardens, homes and swimming pools.
Its venom can kill. Yet nobody has died from a funnel-web bite since antivenom arrived in 1981. The first aid is a firm pressure bandage, then hospital.
4. Blue-ringed octopus
Some blue-ringed octopuses are only about 4.5 cm long. They are usually brown. The bright blue rings only flash when the octopus is disturbed, as a warning.
Its venom is tetrodotoxin. Within minutes it can numb the lips and tongue, then stop the muscles used for breathing. It has killed several people in Australia. But it is shy, and it only bites when someone picks it up.
5. Eastern brown snake
The eastern brown snake has caused more deaths than any other snake in Australia. It copes well with farms and towns, so people meet it more than most snakes.
Brown snakes cause about 1 in 3 hospital visits for snake bite. Even so, only 1 to 4 people die from snake bites in Australia each year. There is antivenom for every native snake.
6. Stonefish
The reef stonefish is the most venomous fish in the world. It looks just like a rock on the sea floor.
Thirteen strong spines on its back can inject venom into a foot that steps on it. The pain is intense. An antivenom has existed since 1959.
7. Redback spider
The redback lives all over Australia, often in sheds, gardens and towns. Only the female’s bite is dangerous. It causes pain, sweating and weakness.
More than 250 people a year receive redback antivenom. Nobody has died since it was introduced. To tell a redback from look-alikes, see our guide to black spiders with a red mark.
8. Bull shark
The bull shark grows to about 3.4 metres. It is the only widespread shark that stays in fresh water for long periods. Young bull sharks can live in river mouths for up to five years.
That makes it hard to predict. It swims far up rivers, often in murky water. The Australian Museum says it is probably behind most shark attacks in and around Sydney Harbour.
9. Common death adder
The common death adder has a triangular head, a short thick body and a thin tail. It lives in forests, grasslands and heath across most of Australia.
Most Australian venomous snakes go looking for food. The death adder does not. It sits still and waits for frogs, lizards and birds to come close. Because it stays put instead of moving away, it is easy to step near one without seeing it.
10. Southern cassowary
The southern cassowary is a huge bird from the rainforests of far north Queensland. It stands about 1.7 metres tall and cannot fly. Each foot carries a claw up to 12 cm long, and its kick can badly injure a person.
Yet only two human deaths have ever been recorded, in 1926 and 2019. Most attacks happen when a bird is defending its food, eggs or chicks. In three out of four cases, people had fed the birds before. So never approach or feed one.
People are a far bigger threat to cassowaries. The bird is endangered, with fewer than 5,000 left in the wild, and cars and dogs kill many of them.
First aid everyone should know
Most of these animals can be treated, and the right first aid buys time. This is what Healthdirect, the Australian government’s health advice service, recommends.
Snake bite. Get the person away from the snake and call triple zero (000). Keep them still and calm. Put a firm pressure bandage over the bite, then a second bandage starting at the fingers or toes and working up the limb. It should be tight enough that you cannot easily slide a finger under it.
Do not wash the bite. Venom left on the skin and clothes can help doctors work out which snake it was. Never cut the bite, and never tie a tourniquet, which is a strap to stop the blood flowing.
Jellyfish sting in tropical waters. Call 000 and ask for an ambulance. Pick off the tentacles, or wash them off with sea water, never fresh water. Then pour vinegar on the sting. Vinegar switches off the stinging cells that are still on the skin.
What really causes the most harm
In 2017, a team led by Dr Ronelle Welton looked at every death from a bite or sting in Australia between 2000 and 2013. The results surprised a lot of people.
| Cause | Deaths, 2000 to 2013 |
|---|---|
| Horses (thrown or trampled) | 74 |
| Snakes | 27 |
| Bees and wasps | 27 |
| Ticks and ants | 5 |
| Box jellyfish | 3 |
| Spiders | 0 |
Bees and wasps also sent the most people to hospital, more than spiders or snakes. For most people, an allergy to a bee sting is a bigger risk than any snake.
Three things people get wrong
Spiders do not kill lots of Australians. Between 2000 and 2013, not one person in Australia died from a spider bite.
The most venomous snake is not the deadliest. The inland taipan has the most toxic venom of any snake in lab tests. But it lives in remote country and is rarely met. Only a handful of people have ever been bitten, and all of them survived.
These animals are not hunting people. Many only bite or sting when they are touched or trodden on. A blue-ringed octopus, for example, bites only when it is picked up.
Did you know? The inland taipan has the most toxic venom of any snake in laboratory tests. Yet only a handful of people have ever been bitten by one, and all of them survived with first aid and hospital care.
Try it
With a grown-up, practise a pressure bandage on an arm, never on a real bite. Wrap a wide roller bandage firmly from the fingers up towards the shoulder. It should be tight enough that you cannot easily slide a finger underneath.
Knowledge check
Between 2000 and 2013, how many Australians died from spider bites?
Show answer
None. A study of coronial records found no spider deaths in that time. The last funnel-web death was in 1980, just before antivenom arrived.
What makes the death adder different from most Australian venomous snakes?
Show answer
It hunts by ambush. Instead of searching for food, a death adder sits still and waits for frogs, lizards or birds to come close.
Frequently asked questions
What is the most dangerous animal in Australia?
It depends how you measure it. The box jellyfish and saltwater crocodile are among the deadliest if you meet one, but a study of 2000 to 2013 found horses killed 74 Australians, more than all venomous animals combined.
Which Australian snake kills the most people?
The eastern brown snake has caused more deaths than any other snake in Australia, according to the Australian Museum. Between one and four people die from snake bites in Australia each year, and there is antivenom for every native snake.
Has anyone died from a spider bite in Australia recently?
Not for decades. The last recorded funnel-web death was in 1980, just before antivenom arrived, and a study of 2000 to 2013 found no spider deaths anywhere in Australia.
What should you do if stung by a box jellyfish?
Call 000, flood the sting with vinegar for at least 30 seconds and give CPR if the person stops breathing, according to the Australian Museum. Remove any tentacles with tweezers or a stick, not bare hands.
Is the blue-ringed octopus dangerous?
Yes. The blue-ringed octopus carries tetrodotoxin, a venom that can paralyse the muscles used for breathing within minutes, and it has killed several people in Australia. It is shy and bites only when someone picks it up.
Why are bull sharks dangerous?
Bull sharks can live in fresh water for long periods, so they swim far up rivers where people do not expect sharks. The Australian Museum says they are probably responsible for most shark attacks in and around Sydney Harbour.
What is Irukandji syndrome?
Irukandji syndrome is what can happen after a sting from the tiny Irukandji jellyfish of northern Australia. Symptoms start 20 to 30 minutes after the sting and include severe pain in the back, stomach, chest and muscles, a racing heart and vomiting. In severe cases it can damage the heart, so it needs hospital treatment.
What is the first aid for a snake bite in Australia?
Call triple zero (000), keep the person still and calm, and put a firm pressure bandage over the bite and up the limb. Do not wash the bite, cut it or use a tourniquet.
Sources
- ABC News (2017): Welton study of bites, stings and horse deaths — deaths and hospital admissions from venomous animals, 2000 to 2013, and horse-related deaths
- Australian Museum: box jellyfish — size, range, season and first aid
- Australian Museum: Sydney funnel-web spider — wandering males and no deaths since antivenom
- Healthdirect Australia: snake bites — snake bite deaths, brown snake hospital visits and snake bite first aid
- Australian Museum: bull shark — fresh water tolerance and attacks around Sydney Harbour
- National Geographic: is the cassowary really the world’s most dangerous bird? — size, claws, the two recorded deaths and why most attacks follow feeding
- Australian Museum: Irukandji jellyfish — the Irukandji’s size and where and when it is found
- Healthdirect: jellyfish stings — Irukandji syndrome and first aid for tropical jellyfish stings
