1000 times worse than cyanide: Blue-ringed octopus bite can turn deadly, quickly

Shortly after a dip at Balmoral Beach, Jaun-Paul Kalman found himself lying paralysed in a Royal North Shore Hospital bed. He was sapped of strength, his body crushed by the phantom weight of an “elephant”, eyes rolling back into his head. But he was entirely lucid.

“I could hear everything. I could see everything. I could feel [medical staff] touching me. I was just completely paralysed,” Kalman, 43, told Nine News.

Jaun-Paul Kalman was rushed to hospital on February 5 after a blue-ringed octopus bit him on the thumb at Balmoral.

“I could feel myself not breathing … I was thinking, oh God, is this the end?”

One of the peculiarities of blue-ringed octopus venom – potentially 1000 times more toxic than cyanide – is that it leaves victims conscious as they suffocate. The octopus hit Kalman with so much venom he was wracked with another three bouts of paralysis in the week after the bite.

One expert says encounters between the deadly creatures and people seem to be increasing.

Kalman was nipped on February 5 by the parrot-like beak of a pulsating, “pissed off” blue-ringed octopus that latched onto his thumb after he picked up a shell in waist-deep water. Mosman Council issued an alert a few days later warning beachgoers of a spate of bites at Balmoral within a week.

In January, a 13-year-old girl also survived a bite in Batemans Bay after a blue-ring swam under her swimmers and latched onto her back.

Blue-ringed octopuses flash their distinctive markings when threatened.Credit: Source: Museum Victoria / Photographer: Julian Finn

“This is the first year I think I’ve heard of two bites in a summer,” marine ecologist at the University of South Australia Dr Zoe Doubleday said. “They’re not aggressive animals; bites are rare.”

The octopuses are smaller than 20 cent coins and have short life spans of seven months. Their favoured hunting grounds of intertidal flats bring them close to rock pool fossickers and paddling beachgoers.

Breakwalls, groynes, lobster pots and discarded bottles and cans could provide human-made habitats for the crevice-seeking octopuses in places busy with people too.

Encounters could be increasing due to more people heading to the beach or because of a spike in octopus populations, but there’s no specific data on blue-ringed octopus numbers to back this up, Doubleday said.

The cephalopod researcher led a study in 2016 that found populations of many octopuses, squid and cuttlefish were booming, probably due to warmer waters under climate change accelerating their breeding cycles.

“They’re fast-growing and short-lived, which means they can adapt to new environments quickly. You get these natural boom-bust populations,” Doubleday said.

There’s a mystery behind why some blue-ring bites are deadlier than others.

“With that octopus on the girl’s back, it’s trapped in a life and death situation … you would have thought she got the full whack and had the full catastrophic effects of that toxin. But she was fine.”

The octopuses are armed with tetrodotoxin, a super-potent poison also found in puffer fish and predatory moon snails.

The venom blocks signals firing between nerves and paralyses voluntary muscles, which stops victims from breathing but keeps them conscious.

They don’t generate the toxin themselves. It may be created by bacteria within their venom glands or have an environmental source such as diet.

A warning to swimmers at Woolwich Baths last March.Credit: Rhett Wyman

“It’s something we know very little about these animals; is it certain times of year, or particular species or habitats, where they are more dangerous?”

Experts warn beachgoers to be careful picking up empty shells or bottles at the beach that may serve as an impromptu blue-ring den. The creatures only flash or bite when provoked.

The bites are often painless, leaving victims unaware they’ve been envenomed.

Symptoms include a tingling mouth, mild weakness and, in severe cases, paralysis and the inability to breathe. Any suspected bite victim should be taken to hospital.

Blue-ringed octopuses may lurk in shells, bottles or rock pool crevices.Credit: Alamy Stock Photo

There’s no antivenom, but symptoms usually abate quickly in hospital. Kalman was sedated with ketamine during his treatment. He said he went on the “worst mind trip you could ever imagine” and clutched one of his children’s toys for comfort.

“They reminded me to keep fighting and stay alive for them,” he said of his kids.

Doubleday said she was taught that blue-ringed octopuses don’t tolerate big swings in salinity, but reports of the creatures living deep into harbours and thriving in hyper-saline inland lakes challenge that thinking.

Last March, a warning sign cropped up in Woolwich Baths on the lower north shore – 10 kilometres from the open ocean – after a boy picked one up.

“Things surprise you with them. There’s still so much we don’t know.”

There are three named species, including the blue-lined octopus species common in Sydney.

Senior curator of marine invertebrates at Museums Victoria, Dr Julian Finn, has identified dozens more unnamed species across Australia and the Indo-Pacific. He’s working on the taxonomy and venom analysis of the different species.

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