Family members of one of the men who died after a boat capsized near Port Lincoln late on Monday have paid tribute to the “adventurer who loved fishing”.

Alan Leslie Bottrill, 71, was among three people who died when their boat was swamped by a wave off South Australia’s Eyre Peninsula around 4pm on Monday.

His body and the bodies of the two other victims, Paul Eckert and his son Tom, were retrieved from the water on Tuesday.

Paul Eckert was one of the victims of the Spilsby Island tragedy.(Facebook)

Another of Paul’s sons, Flinders University sleep expert Professor Danny Eckert, and Danny’s 12-year-old son survived by clinging to a reef off Spilsby Island, 45 kilometres east of Port Lincoln, where they were found about 2am on Tuesday.

In a statement released on Wednesday, Mr Bottrill’s wife Pamela and children Rónán and Amélie expressed their grief.

“Alan was 71 years old and still very much an adventurer who loved fishing, golfing and travelling with friends and family,” they said in the statement.

“He leaves behind a wife, two children and two grandchildren who will miss him very much.”

Tom Eckert was one of the three men killed in the boating tragedy.(Facebook)

The family extended a “heartfelt thanks” to everyone involved in the search efforts including police, who “did a wonderful job”, and the “community that has gathered around to support and care for our family”.

“Our most heartfelt thoughts are with the families of everybody affected by this tragedy,” Mr Bottrill’s family said.

Ms Bottrill told ABC News she understood a “megawave” had struck the 6.2-metre fishing boat, and that there had been no time to activate new safety gear which had recently been installed.

She said her husband was an experienced fisher who had twice battled cancer and “never” thought he would have been killed fishing.

Mr Bottrill was described by his family as an “adventurer who loved fishing”.(Supplied)

Survivors battled ‘daunting’ seas

Police began searching for the missing boat after family members raised the alarm about 8:30pm on Monday when the vessel failed to return from a fishing trip.

A police helicopter located the upturned fishing boat about 2am on Tuesday.

It was brought back to shore aboard commercial fishing vessel Delamere.

The vessel capsized off Spilsby Island.(ABC Eyre Peninsula: Jodie Hamilton)

SA Police’s Superintendent Paul Bahr told ABC Eyre Peninsula the duo who survived had to contend with a 1.5-metre swell as they clung to the reef.

“Because they were at a reef, they would have had the odd breaker breaking onto that reef so I think it would have been pretty daunting,” he said.

“I think they are incredibly lucky and it speaks a lot about their own resilience that they managed to hang on.”

Professor Danny Eckert survived the disaster by clinging to a reef.(Supplied: Danny Eckert)

He said the search – which included “selfless” efforts from local fishing vessels, the P&O cruise ship Pacific Explorer and a cargo ship – was assisted by teams on land.

“A lot of the search is guided by people remote from the actual search area who are running algorithms across drift patterns and swell patterns and tides to determine where debris and individuals may float and drift as the days go on,” he said.

“There’s a lot of work goes into ensuring that we put a bit of intelligence into this and make sure that our searches are concentrating in the right areas and that’s where we get this sort of result.”

Mr Bottrill’s family paid tribute to all those involved in the search.(Supplied)

Superintendent Bahr said the involvement of local fishing vessels in the search had been “critical”.

“Port Lincoln is remote from the rest of the state and so we are very self-reliant. We are reliant on the good will of volunteers to help us and we are fortunate that we have such a large fishing fleet here,” he said.

“The crews like the Delamere were pretty selfless in the support they gave us.”

He urged anyone planning a fishing trip to ensure they have working and up-to-date safety equipment, and ensure everyone aboard knows how to use it.

He said a report would be prepared for the coroner.