The body of a middle-aged man without a lifejacket was found floating in Auckland's Waitemata Harbour yesterday, reviewing safety calls.

The man, believed to be in his 50's, was discovered about 500m from the Marine Rescue Centre headquarters in Mechanics Bay about 3pm by a couple sailing past in their 40ft launch.  Police were lastnight looking for his car and trailer to confirm his identity and inform next of kin.

The man was lying face down and fully clothed and his 16ft runabout was floating overturned nearby.

Sergeant Martin Paget of the Police Maritime Unit said the woman who spotted the body tried to resuscitate the man but he was already dead.  The Westpac Rescue Helicopter and Coastguard carried out an air and sea search for about an hour before confirming only one person had been on the boat.

Paget said the water was "rough" but they did not know how the man came to be in the water.  "The boat, for some reason unknown, had turned over near Mechanics Bay," he said.  "The only vessel that saw him, despite there being a number of boats around, was a couple in a launch that was passing by him."  "They spotted what they thought was a corpse and got alongside him and tried to revive him.  A paramedic attended and tried to help, but unfortunately it was too late.  We won't know how this has all come to happen until the investigation continues next week."

Paget said the man had a lifejacket on board but was not wearing it.  His death served as a tragic reminder to other boaties to always wear a lifejacket.

"Where it happened was basically in spitting distance of the Coastguard, police and paramedics who could have potentially helped him earlier if he had been wearing a lifejacket.  It's extremely unfortunate."

Sophie Hazelhurst of Maritime New Zealand said about 60% of recreational boating deaths were caused by people not wearing lifejackets.  "The message is getting out there but many people do take a 'she'll be right' attitude," said Hazelhurst.  "People don't think it's going to happen to them and they don't realise how quickly things can go wrong."

Hazelhurst said the National Pleasure Boat Safety Forum - an advisory group including Maritime NZ, Coastguard and Water Safety New Zealand - was aiming to enable harbourmasters to issue infringement notices on anyone not wearing a lifejacket.  "Our aim is to make it as automatic as putting on a seatbelt."