A couple has spotted one of Australia's deadliest sea creatures hiding out in the deep in Sydney Harbour last week. As underwater photographer Duncan Heuer and his girlfriend were scuba diving 50 meters from shore at Camp Cove Beach in Watsons Bay, they spotted a blue-ring octopus covered under the sand.

Heuer said he was trying to set up his camera to capture a sea spider he had spotted when he noticed a creature flashing at him on the rocks. He told news.com.au how he seemed to have disturbed the octopus as it flashed at him to go away.

Marine biologists say the octopus flashes its bright colors whenever it feels threatened, but will only attack or bite when being poked, stepped on, or harassed. The species is believed to possess enough poison in its body to paralyze and kill 26 adult humans within minutes.

Despite the potential danger, Heuer is undaunted by being near the creature. He said the octopus began to curl its tentacles and flashed its bright colors as it moved a safe distance away from him.

Heuer adds that the only way a person would get bitten is if they would grab one and pull it out of the water.

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Blue-ringed Octopus Facts

The blue-ringed octopus is only eight inches long but is one of the most venomous sea creatures in the ocean. It preys on crustaceans and fish and bites them to inject its poison.

The species usually dwell in shallow waters of rocky shores in Australia and Japan. They get their name from the bright blue rings that throb just before they bite, which serves as a warning for other animals or threats to keep away.

Unfortunately, both the male and female blue-ringed octopus die during reproduction. After fertilizing the eggs, the male immediately dies. The female makes it through the process but will refuse to eat for one to two months of gestation to make sure she guards the eggs well and not let them out of her sight.

What Happens When a Blue-Ringed Octopus Bites?

Blue-ringed octopuses are not aggressive by nature and usually only bite as an act of self-defense. This usually happens when a predator attacks or when a human picks them up or steps on them.

According to the University of California, Santa Barbara, the blue-ringed octopus has a certain kind of venom in its mouth. When it bites, it injects venom that can paralyze a person's muscles.

What makes it dangerous is that it could also paralyze the lung muscles that allow us to breathe. When this happens, soon, there will be no oxygen left in the victim's blood. After a few moments, the heart will also shut down.

Additionally, the brain could also lose function after four to six minutes without oxygen. However, if only a small amount of poison gets into the system, there is a chance that the person may still recover.

Despite the sea creature's high toxicity, there have only been just three recorded deaths related to the octopus in the last century. Two cases were recorded in Australia and one in Singapore.

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