Aussies are being reminded ahead of summer to always check rock pools at beaches before swimming after a little boy's dangerous encounter with a deadly blue-ringed octopus.
The child was swimming at Fairlight in northern Sydney on Saturday when one attached itself to his foot, prompting his worried mum to notify others who might not "realise the danger".
"Just a reminder to check rockpools when kids are playing in them," the Sydney woman posted on Facebook after a day at the beach. "This guy was climbing on my son's foot today at Fairlight (lots of little kids)."
The mum explained that the sea creature was "brown until it became agitated". "Then bright purple rings," she added, saying it appeared to be "really angry".
Venom 1000 times more powerful than cyanide
According to the Australian Museum, the blue-ringed octopus uses "an extremely powerful venom" to kill its prey including crabs and small fish. The octopus can also use this venom, known as tetrodotoxin, on humans which can cause paralysis and death.
The venom of a blue-ringed octopus is known to be 1,000 times more powerful than cyanide on humans. There have been two fatalities from a blue-ringed octopus in Australia, according to the Australian Institute of Marine Science. The marine animals are also found in Asia.
Aussies warned to stay clear of deadly blue-ringed octopus
The behaviour described by the Sydney woman is pretty normal when the animal is "startled" or feels "threatened", according to Dr Julian Finn, Senior Curator for Marine Invertebrates at the Museums Victoria Research Institute.
"If you see this display from a blue-ringed octopus, you are probably too close," he previously told Yahoo News Australia.
In September, after a sighting at a rock pool in Bronte, Sydney, a spokesperson for Surf Life Saving NSW urged people to "be careful when exploring rock pools".
"Blue-ringed octopuses are small and well camouflaged but they have enough venom to kill 26 adults within minutes," he warned.
'Timely reminder' for Aussies ahead of summer
Members of the community's Facebook page thanked the mum for sharing, with many admitting their own kids regularly play barefoot in the rock pool.
"Thanks for posting, my two-year-old keeps taking his shoes off to stomp in rock pools," one person shared. "Very lucky that didn’t end differently," said another.
Meanwhile, a third pointed out that it's a "timely reminder that you can't see the blue rings until they become agitated".
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