Atlantic Aqua Farms of P.E.I. has made a complaint to the RCMP about damage to its shellfish lines on the Brudenell River.
Company manager Dana Drummond told CBC News six lines have been cut over the past two weeks.
"I have no idea. I just make some assumptions and assume that pleasure boaters are getting caught up in them for some reason. I'm not sure if they're boating after dark or what," said Drummond.
"I cannot see anybody doing it deliberately. We've been in this business a lot of years and like last year we had one incident."
In that case, said Drummond, the boater got caught in a line and called the company.
The six cut lines could cost the company as much as $9,000. The lines are pieces of rope that collect mussel seed in the water.
RCMP say they don't know yet if the damage to the lines was deliberate or accidental. Kings District RCMP are asking the public to call if they see anyone tampering with these lines or driving over them in any type of watercraft.
There are clearly visible markers showing the location of the lines, say police. They are asking boaters to stay well away from those areas.