Police on the water in the Bay of Islands are disappointed 70 per cent of people they have checked were not wearing lifejackets and some failed to have enough for everyone on board.
"I would like to think that people are learning but for some reason a lot of people aren't and they are dying as a result," said Senior Sergeant Martin Paget, officer in charge of the Police Maritime Unit.
On December 28 three fishermen not wearing lifejackets were rescued from rocks about 4km off Karikari Peninsula.
The trio had set off the day before and had to be winched to safety by the Northland Electricity Rescue Helicopter. Officials said they were lucky to survive.
"Most people don't understand how dangerous it can get very quickly," Mr Paget said.
The police unit's 12-metre inflatable boat, one of three in the country, has been patrolling the Bay of Islands since December 30 and its last day was today.
Of the 30 or so boat crews the police were speaking to each day, about 70 per cent were not wearing their lifejackets or did not have any with them.
It was the first time in about 10 years a police boat had patrolled the area, Mr Pagent said. While the officers might be called on to make arrests or help with search and rescue, the role predominantly focused on prevention.
Constable Rhys Dempster, of Kerikeri, said the boat had been "very busy" since it had been on the water.
"I think it is going to be a thing of the future for the Bay of Islands," he said.
One of the most common, but stupid, situations the officers were coming across was parents putting lifejackets on their children but refusing to wear one themselves. "If you fall over the side, how is your 3 or 4-year-old daughter going to drive the boat?" Mr Dempster said.
Another common issue was divers not putting up a flag to alert boaties, which was especially dangerous with so many more people around at this time of the year.
Each regional council sets its own rules regarding lifejackets. In Northland boaties must wear lifejackets if they are in a paddle or oar-propelled boat. In all other cases there must be one lifejacket per person on board and they must be readily available if needed.
Mr Dempster said he hoped to remind people of those kinds of rules.
"If we can stop one drowning this year we've succeeded."