Leaders from several B.C. First Nations took to the water on Sunday to serve an eviction notice to the province’s largest producer of farmed fish.

Elders and heredity chiefs from six different nations boarded boats just off the coast of Port Hardy, B.C. to tell Marine Harvest to pack up and leave. They believe fish farms spread disease and are hurting wild salmon.

“This is our territory and we need to protect it,” said James Wadhams, a Kwakiutl First Nation elder. “The amount of fish have just been declining and declining since they’ve been here.”

But those working in B.C.’s aquaculture industry disagree.

“There’s no direct evidence that salmon on farms are causing ill health in wild salmon,” said Jeremy Dunn, executive director of the BC Salmon Farmers Association recently told CTV News.

Marine Harvest says it has agreements and positive relations with 15 First Nations in B.C.

Although aquaculture is divisive in B.C., the industry supplies just under half of the fish people consume globally.

A study released in 2016 from Dalhousie University found two thirds of the world’s fisheries were declining. Some see aquaculture as a solution to the depletion of the world’s fisheries.

Sunday’s open-water demonstration is the latest conflict to rock B.C.’s fish farm industry. Last fall, there were demonstrations across the province and members of several First Nations occupied a handful of aquaculture sites.

In November, shocking video emerged showing blood from a salmon processing plant near Campbell River, B.C. pouring out of an underwater pipe and into the ocean. The waste tested positive for piscine reovirus, or PRV, a virus commonly found in farmed salmon that scientist say can spread to wild fish.

Both the provincial and federal governments launched reviews after seeing the footage.

“Obviously if there’s an appropriate enforcement action that will take place it will take place,” Dominic LeBlanc, Canada’s minister of fisheries and oceans, said back in November.

While this eviction noticed is likely symbolic and there’s no sign Marine Harvest will move out of B.C. anytime soon, some of its leases expire in June.

With reports from CTV National News B.C. bureau chief Melanie Nagy and CTV Vancouver’s Bhinder Sajan