Extensive search efforts for a father missing off a Torres Strait island have been unsuccessful after the discovery of an unmanned outrigger canoe.

The vessel was found 100 metres offshore from Thursday Island on Wednesday afternoon, triggering a major sea and air search for the missing 38-year-old man.

The paddler was last seen about 3.45pm before his hat was found on Channel Rock by a member of the public.

Efforts to find him in the channel between Horn and Thursday Islands had been bolstered by members of the tight-knit community, Acting Inspector Andrew Pool said.

“The missing man has strong ties to the community here and is a much loved and valued father, partner, son and friend to many and everything possible is being done to locate him,’ he said in a statement on Friday.

Conditions have been challenging at times with rough seas and winds, and no more items of interest have been found.

“As time progresses, grave fears are held for the man’s welfare and every support is being offered to his family,” Insp Pool said.

“The search will continue until nightfall, with several water police vessels along with private boats, and rotary aircraft taking part.”

Boaties have been asked to immediately report sightings to police.

– AAP