top 10 deadly animals in Australia

1. Box jellyfish

A box jellyfish.

Image: Melanie Stetson Freeman

Highly dangerous, the box jellyfish is usually found in northern Australia during the warmer months — exactly when you want to swim.
They're called box jellyfish because their bell — the top of the jellyfish — has four corners, as well as clusters of trailing, stinging tentacles that can stretch more than two metres (6.4 feet), Robinson said.
Human encounters occur most often when the box jellyfish comes close to shore to breed in estuaries. "That type of water is muddy, so you can't always see them and they can't see you," he added. If you're in the murky water and brush against one, you can easily be stung.
Danger rating: 10/10
Scientific name: Chironex fleckeri
How to know if it's got you: A box jellyfish sting can be unbelievably painful, Robinson said. The venom is designed to paralyse fish, so it immobilises your nerves and affects breathing and movement. A large dose can cause cardiac arrest and death within minutes.

2. Honey bee

The European honey bee.

Image: Patrick Pleul/Associated Press

The humble honey bee, which is not native to Australia, comes second on the list because it's both common and deadly to small subset of people. Being stung by 100 or so honey bees could put anyone at risk of a fatality, but for those who are highly-allergic, even a single sting can be a life threatening situation.
"The honey bee has barbed stings, so it can only sting once," Robinson. "The purpose of the sting is to make you never want to bother a bee ever again."
Danger rating: 9/10
Scientific name: Apis mellifera
How to know if it's got you: You'll suffer a sharp, burning pain and minor swelling, unless you're allergic, in which case a sting could cause swelling and severe breathing difficulties, among other symptoms.

3. Irukandji jellyfish

A fully grown Irukandji jellyfish.

A type of small box jellyfish, the Irukandji jellyfish can be the size of a finger nail in the bell, and its tentacles can be up to one metre (3.2 feet) in length.
Scientists are not certain of the full range of locations where they occur, Robinson said, but there have been remarkably similar stings along the Australian coastline. While the box jellyfish is usually found in shallow water, the Irukandji jellyfish is most often in deep water.
Danger rating: 9/10
Scientific name: Carukia barnesi
How to know if it's got you: Getting stung by these little buggers can bring on Irukandji syndrome. Taking about 30 minutes to set in, the syndrome can be marked by severe lower back pain, cramps, sweating, anxiety, nausea and other, more fatal, symptoms.

4. Bull shark

A bull shark.

Image: Corbis Images

Found worldwide in coastal waters, you're most likely to come across the bull shark in estuaries, harbours and rivers.
It's a very good scavenger, as well as a predator, Robinson said, so you certainly don't want to be swimming near any dead whale carcasses. It's probably responsible for most of the dogs that go missing from the water, he added.
Danger rating: 8/10
Scientific name: Carcharhinus leucas
How to know if it's got you: Oh, you'll know.

5. Eastern brown snake

Image: William West

The brown snake group is likely responsible for the most snake bite fatalities of any Australian snake genus, Robinson said, probably because the species is found all over Australia.
Usually more than one metre (3.2 feet) in length, it's a very nervy snake, he added, so if you come close they can strike out and bite you quickly.
Danger rating: 8/10
Scientific name: Pseudonaja textilis
How to know if it's got you: According to the Australian Museum, the eastern brown snake's bite can initially be painless and difficult to detect. That's a problem, because if bitten, you'll need medical attention straight away. Its venom can result in eventual paralysis and uncontrollable bleeding.

6. Saltwater or estuarine crocodile

A 4.5 meter (13.5 foot) saltwater crocodile.

Image: Rob Griffith/Associated Press

Living in northern Australia, saltwater crocodiles can be found in the ocean, but they are more likely to be in estuaries, and occasionally, freshwater.
Take notice of what the locals tell you and take any cautionary signs seriously, Robinson advised, because the saltwater crocodile is very good at ambushing prey. And word to the wise, don't leave your dog chained up outside the tent.
Danger rating: 8/10
Scientific name: Crocodylus porosus
How to know if it's got you: The sharp teeth clamped around your leg is a definite clue.

7. Sydney funnel web spider

A Funnel Web spider.

Image: Ian Waldie

Most of Sydney's north shore suburbs are built on the main population area of the Sydney funnel web, according to Robinson. Since 1927, 14 deaths from the spider have been recorded. It's only the male bite that has proved fatal, however.
Direct UV light will kill a funnel web, so the spiders need somewhere to hide during the day and have been known to consider a shoe a perfectly adequate location. More commonly, the spiders builds burrows under something like a pile of bricks or a log.
Danger rating: 8/10
Scientific name: Atrax robustus
How to know if it's got you: The venom of a Sydney funnel web can cause death, as it contains a neurotoxin component that affects the nervous system. The bite is very painful, and symptoms include sweating, tingling and muscle spasms.

8. Blue-ringed octopus

A swimming blue-ringed octopus.

Image: Corbis Images

There are about four species of blue-ringed octopus around the Australian coast. They are normally brown and innocuous looking, but when disturbed, iridescent blue lines and rings appear.
Almost all bites have occurred when the octopus was picked up and taken out of the water, Robinson said. The simple message is: don't touch them and you'll be fine.
Danger rating: 7/10
Scientific name: Genus Hapalochlaena
How to know if it's got you: Once bitten by this octopus, symptoms can appear within minutes, depending on where you've been bitten. Because it contains neurotoxins, the body starts to shut down and becomes increasingly paralysed. Usually victims die because they stop breathing, Robinson added.

9. Coastal taipan

A coastal taipan.

Image: Corbis Images

Around two metres (6.4 feet) on average, the coastal taipan is not an aggressive snake, but it's very able to defend itself with a fast and accurate strike. The inland taipan beats the coastal taipan for the severity of its venom, Robinson said, but people rarely encounter it and there have been no known deaths.
Danger rating: 7/10
Scientific name: Oxyuranus scutellatus
How to know if it's got you: The coastal taipan's venom is designed to work on mammals such as rats and works very quickly. The venom attacks the nervous system and blood. If bitten, you might start to bleed internally, as well as suffer headaches, nausea and vomiting.

10. Common death adder

A common death adder hides in leaf litter and uses its tail as a lure for unsuspecting prey.

Image: Auscape

Quite widespread in Sydney bushland, the reason this snake is at number 10 is that it relies on camouflage rather than evasion to protect itself, according to Robinson. While other snakes will slink off when faced with a threat, the death adder freezes, he said, so it's easy to get bitten if you're walking through a bushy area and step on one. Its fangs are long and can penetrate quite deeply.
Danger rating: 7/10
Scientific name: Acanthopis antarticus
How to know if it's got you: The common death adder's venom causes loss of motor and sensory function — you go numb and your respiration starts to slow, and eventually, paralysis and even death can occur.