The patrols have been set up after a string of break-ins in the carparks at Smaills Beach, where thieves have been targeting surfers out trying to catch a wave.
Tomahawk resident Lloyd McGinty said locals wanted to let the thieves know they were watching.
He and a coalition of other Tomahawk locals were now patrolling the eastern end of Tomahawk Rd during peak surfing times.
"I’ve even thought of putting up some posters, letting them know we’re watching," Mr McGinty said.
Residents had also been sharing information about the thefts on the "HAWK TALK Community Group" Facebook page.
Mr McGinty said the thieves were mainly targeting the vehicles of surfers who were out on the water.
He had been made aware of eight thefts this winter alone.
A surfer whose vehicle had been targeted said thieves were taking advantage of the fact they were out on the water for long periods.
"I think they know surfers, they know that we’re not going back for an hour or two hours, we have to leave everything in the car, and they know that."
The fact the beaches were largely empty during the winter months, apart from the surfers, also made them a target.
The surfer had been reaching out to others in the community, including Mr McGinty and police, and hoped bringing everyone together could solve the problem.
Another surfer, Seiji Kawaguchi, who was the victim of a similar theft last month, is also calling for action to be taken.
"We need to take it seriously, make police reports, make the community move ... they’re small things but will definitely help protect people."
Sergeant Matthew Lee, of Dunedin, confirmed police were aware of thefts in the area.
"Dunedin police are aware of three incidents involving vehicle crime in Tomahawk in the last month."
Sgt Lee urged anyone with information to contact police on 105.
For Mr McGinty, the solution was simple.
"We have had this issue come and go over the years ... it typically stops when the offenders know the community are involved."
