IT IS a good thing Harrison Bycroft watches Animal Planet.
The savvy eight-year-old picked up his younger brother Archer, 5, and ran up the beach to save him from the temptation of touching a blue-ringed octopus at Currimundi Lake.
His mum Nicole didn't believe Harrison when he shouted out that he had found one of the deadly creatures in the popular swimming spot on Saturday.
But sure enough, a 15cm-long mottled brown octopus with distinctive blue rings was sitting in about 20cm of water.
"It was very close to where lots of children were playing in the lake," Nicole said.
"I was very surprised to see one in there."
Harrison continued to play the family protector, cautioning his mum to stay well away as she took photos.
"He knows everything when it comes to animals and was reminding me that it was very deadly," Nicole said.
But the blue-ringed octopus is not as uncommon as you might think.
In fact, University of the Sunshine Coast associate professor in marine science Thomas Schlacher said they were a dime a dozen.
"There are hundreds of them in Pumicestone Passage, Currimundi Lake and the Maroochy, Mooloolah and Noosa rivers, you just don't see them," Dr Schlacher said.
"They like to be in sheltered marine waters with a little bit of freshwater inflows and will hide under anything from a bit of rock to fallen wood.
"This one might have been disturbed or dislodged from his hiding place."
Although the small species is highly venomous, Dr Schlacher said they only released their powerful nerve toxin if they were severely agitated.
"It is also good to remember that they can be any odd colour as they blend into their backgrounds. Their rings only show up when they feel threatened," he said.
"Octopuses are not something you want to play with - ever. Leave them be, unharrassed in their little octopus world."
Sunshine Coast lifeguard supervisor assistant Trent Robinson said a blue-ringed octopus sting should be treated with pressure immobilisation, similar to that of a snake bite.
"Bandage up the whole limb and call an ambulance straight away," he said.
"The sting itself is not painful, so it's hard to know you have been stung unless you have seen it happen."
National Geographic Australia reports there have been no deaths from blue
ringed octopus since the 1960s and hospitalisations are also uncommon.
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