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The blue-ringed octopus is just one of many venomous creatures found in Australian waters. Amber Hansen, Author provided

Don’t go in the water: a world of pain awaits in Australia’s deep blue seas

Australia’s reputation for deadly creatures of all kinds is known the world over. Tourists worry about it, and comedians have a field day with it. Here’s what Bill Bryson says in his book In a Sunburned Country:

[Australia] has more things that will kill you than anywhere else. Of the world’s ten most poisonous snakes, all are Australian. Five of its creatures – the funnel web spider, box jellyfish, blue-ringed octopus, paralysis tick and stonefish – are the most lethal of their type in the world.

Bryson certainly has a way with words. But, to be honest, he forgot a few things.

The long list

Australia has at least nine species of Irukandjis, a group of jellyfish so nasty that their drop-for-drop toxicity leaves the box jellyfish in the dust.

Impressive, considering the box jelly has long been considered the world’s most venomous animal. A massive sting from a box jelly kills in as little as two minutes; for other victims, it’s generally painful with some scarring, but that’s about it.

Irukandji, in contrast, with just an imperceptible brush of venom leaves almost no mark. But after about a half hour you develop Irukandji syndrome, a debilitating mix of nausea, vomiting, severe pain, difficulty breathing, drenching sweating and sense of impending doom. You get so sick that your biggest worry is that you’re not going to die!

And that’s just the beginning: up to a third of victims require life support and a quarter have ongoing complications, including permanent heart damage or neurological damage.

Bryson also forgot the blue bottles that sting some 25,000 to 45,000 people each year in Australia, at least one species of which causes Irukandji syndrome.

And he forgot the bullrout, which is kind of a brackish-water version of the stonefish – caution, they hang out at boat ramps and these suckers hurt.

And stingrays, which combine stabbing and venom into the one injury. And the cone snail, which looks mild-mannered, but can imperil your life with one stab of its lightning-fast barb.

Then there are sea urchins and stinging hydroids and venomous sponges, which will put you in a world of hurt. But nobody ever thinks to include them.

And the sea snakes: if you get one in your fishing net, or your dive equipment, or your hair, remember the old adage “don’t grab a snake by its tail”. Well, I’m not sure if that’s an adage or not, but it should be. In fact, “don’t grab a snake” would be better.

Bryson also forgot the world’s only venomous mammal, the platypus: males have a venomous spur on the back legs, and they seriously hurt. And my new favourite, the arrow worm. Yes, the arrow worm.

Granted, there aren’t any reported deaths from arrow worms, but they deserve respect. They look like a beansprout with fish fins, with a fish tail at one end and rows of big scary spines at the other, which they use to grasp their food. And they “bite” with tetrodotoxin – the same venom that makes fugu (the pufferfish delicacy) and blue ring octopus so lethal.

And swans. Bryson forgot swans. At least three people have reportedly been killed by swans. I’m just sayin’. (Good news: these are not the native Australian black swans).

But why?

Okay, venomous beansprouts, swans and fear of not dying aside, what is it with Australia’s dangerous creatures? The typical explanation for powerful venoms is subduing dinner or dealing quickly with danger, especially for delicate creatures or those that aren’t able to track prey for long distances.

But certainly the box jellyfish’s venom is overkill, while the Irukandji takes too long. What’s more, fish don’t appear to get Irukandji syndrome … although I’ve never been sure how to tell if a fish is sweating.

Similarly, the dinner-or-danger hypothesis doesn’t seem to hold true for stabbing fish wounds, such as those delivered by stonefish, bullrouts and stingrays. Certainly, the stabbing must be far more effective than all but the most instant venom effects.

But one must keep in mind that these creatures evolved their toxins long before Homo sapiens fossicked the tide pools or snorkelled the reefs. So although their venoms can harm us, this may just be coincidental.

A question that often arises is what effect climate change will have on these creatures or their venoms. Well, the answer is we really don’t know yet.

With regard to species, there will be winners and losers. Many of the venomous sea creatures are tropical, and many tropical species are expanding southward. To what extent this may put the more populated southerly areas at higher risk is still unclear.

One group, however, seems particularly poised to benefit: the jellyfishes. As warmer water stimulates their metabolism, they grow faster, eat more, breed more and live longer. Irukandjis and box jellyfish become more toxic as they mature, so getting there faster and staying there longer could have undesirable outcomes for sea users.

How, then, can we possibly navigate these dangers when curious sea snakes want to swim with us, duckbilled platypus, stones and beansprouts must be viewed with suspicion, blue is sounding like the new warning colour, invisible jellyfish will lay us flat, and even the swans, a symbol of romance, are scary?

Four tips for keeping safe

Rule 1: First and foremost, try to make it a rule never to touch an animal that isn’t a personal friend. This will prevent the vast majority of bite and sting injuries, and not just from sea creatures.

Rule 2: Do the stingray shuffle when moving in sandy water: drag your feet in such a way that you’re continuously kicking sand in front to where you’re about to step. This will scare most creatures away so that you don’t step on them.

Rule 3: Wear protective clothing (a full-body lycra suit, for instance) when swimming in areas where box jellyfish or Irukandjis may appear. If stung by box jellyfish or Irukandjis or unknown jellyfish in the tropics, douse with vinegar to neutralise undischarged stinging cells.

Rule 4: Don’t try to make friends with swans.

Finally, read the Australian Resuscitation Council website for the latest on prevention and first aid for bites and stings.

This article is part of our series Deadly Australia. Stay tuned for more pieces on the topic in the coming days.

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