Three people, including a child, survived floating in the ocean for 16 hours in the ocean off Tasmania after their boat sank on Saturday.

However, one man believed to be a fourth occupant on the boat, was found dead today after a search by land and air.

The four are thought to have been staying at Montagu campground in the state’s north-west when they set off for a fishing trip at around 5.30pm on Saturday.

Tasmania Police confirmed the Westpac Rescue Helicopter is involved in the search for the missing boat. (Sitthixay Ditthavong)

They failed to return, with concerned relatives raising the alarm with police at about 8am yesterday.

On the boat was a 27-year-old woman, a 33-year-old man, a 36-year-old man, and a six-year-old child.

The Westpac Rescue Helicopter was dispatched about 1pm yesterday and two adults and a child were found floating in the water at

Police believe the boat they were in broke up at about 9pm on Saturday, with all four to be thrown into the water.

Three of the people, the 33-year-old man, the woman, and the child, were floating in the water for around 16 hours before being rescued at around 1pm yesterday.

They were taken to North West Regional Hospital due to the amount of time they spent in the water, but police say they are otherwise uninjured.

The trio were wearing life jackets.

However, the body of the 36-year-old was found on the eastern side of Robbins Island this afternoon, police said in a statement today.

It is not known if he was wearing a life jacket.

“Our thoughts are with the man’s family and loved ones at this difficult time,” Tasmania Police said in a statement.

A report will be prepared for the coroner.

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