Lance Karlson, a geologist, and retired lifeguard, was with his two-year-old daughter in Geographe Bay in Dunsborough when he saw the monster in the shallow water, first mistaking it stingray striking a seagull.
Karlson captured some video of the octopus and shared it on Instagram, where it has received over 221,000 views.
He told Insider, "The octopus lashed out at us, which was a total shock."
Aggressive Cephalopods
"My initial reaction to the experience, which I was able to capture on video, was horror, accompanied by curiosity. I had never seen an octopus up close before, but I was more fascinated at the moment. Remember, I was with my daughter, and I'm sure every father can relate to being more defensive of her than afraid of the danger, "Karlson said.
The former lifeguard left the octopus behind and went to put up a shelter for his wife and daughter farther down the beach.
Karlson was floating in the sea on his own about 20 minutes later (having swum there "many years" before) when the octopus reappeared - he was whipped around his left arm when gazing at crab shells in water about 1.5 meters deep.
"My goggles fogged up, the water became murky, and I was shocked and confused," he explained. "I was then slapped a second time around the neck and upper back, this time with greater intensity. I can only characterize it as a stinging accompanied by a 'whipping' feeling."
Octopuses squirt an ink-like liquid when attacked, and Karlson claims he might have been unwittingly in the creature's house.
Karlson swam back to shore, some 25 meters away, but his arm, leg, and upper back were covered with stinging red raised imprints from experience.
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Immediate Action
Karlson, a geologist for 13 years, and his family fled back to their hotel suite, struggling to locate some vinegar, in search of anything acidic to treat his wounds. Coca-Cola was their only choice.
"I wasn't sure if Coke would work," he said, "but considering how acidic it is, I figured it was worth a shot." "It seems to fit."
He didn't go to the hospital and said on his Instagram stories that he's fine now, that the pain and marks were just temporary.
Octopus Attacks
Despite the shock of Karlson's attack, Bryan Fry, an associate professor at the University of Queensland's School of Biological Sciences, told CNN that octopuses do not pose a threat to humans in general.
"It is venomous, like all octopuses, but it is harmless to humans," he added. "The venoms are dramatically more powerful on invertebrates like clams and lobster."
Karlson's story has made international news, much to his amusement.
Karlson spent a college exchange year at Cornell University in 2007-2008 as a geology student. "I recall being asked about the Australian species that frequently make headlines in the United States - our lethal snakes, spiders, great white sharks, and crocodiles - never could I have imagined appearing in one of those stories!" he said.
A Hopeful Ending
Karlson hopes that rather than terror, people will be intrigued and fascinated by his plot.
He described them as "truly extraordinary, brilliant beings with distinctly powerful emotions." "I believe I just happened upon one on a day when it awoke on the Wrong Side of the Room!"
Also Read: Rising Number of Shark Attacks in Australia Reveals A Darker Story
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