Concern is growing for a boatie missing in waters off Victor Harbour, south of Adelaide, after debris was found in the water on Tuesday.

The search for Tony Higgins and his boat, the Margrel, has resumed this morning off Granite Island.

The 57-year-old Goolwa man called police early on Tuesday, saying the boat he had been living on for two weeks was taking on water.

He has not been heard from since.

His boat was last seen at the Granite Island wharf on Monday afternoon.

Debris was located in the water near the island about 4.30pm on Tuesday by an Australian Maritime Safety Authority plane.

Police are investigating whether it is linked to Mr Higgins.

“We are asking anyone who may have had contact from the man on board or who has seen the vessel after 3pm on Monday to contact police on 131 444,” SA Police Senior Constable Dave Muir said.

It is the second major police search for Mr Higgins, after he and his friend Derek Robinson disappeared in waters off Eyre Peninsula earlier in September, sparking the largest maritime rescue mission in the state’s history.

They were found five days later, unaware of the panic they had caused.

On Tuesday, Mr Robinson told the ABC he was worried for his friend’s safety, and hopeful he would be found floating in the ocean in a life jacket.

On Wednesday morning, Alexandrina Mayor Keith Parkes said the outlook “doesn’t look too good” for Mr Higgins and the Margrel.

“In those conditions on this coast, if the boat hasn’t been sighted or found by now, it would indicate something has happened, and if something has happened, the boat has sunk or something like that,” Mr Parkes said.

“The likelihood of surviving would be a miracle really.”

Debris found near Granite Island on Tuesday afternoon. Photo: ABC

‘Atrocious’ conditions yesterday

Sea Rescue volunteers conducted a search for several hours on Tuesday morning but were forced to return to shore as weather conditions worsened.

They and the SA Police Water Operations Unit will search Encounter Bay again on Wednesday.

Authorities conducted an aerial search of the area until 11pm using infrared radar equipment.

Mr Parkes said Tuesday’s weather was “atrocious”, with wind gusts of about 50km/h bringing rain down “pretty well horizontal”.

The former commodore of the Goolwa Regatta Yacht Club said it was possible the boat had come loose from its mooring accidentally during the night and been carried out with the current.

He said he felt for the searchers, particularly the many volunteers.

“Putting their lives at risk in these conditions – it’s terrible,” he said.

Mr Parkes said wooden boats often leaked some water, which could be exacerbated in heavy weather.