New study shows increased pathogens near B.C. open-net salmon farms

A new study led by the Pacific Salmon Foundation and four northern Vancouver Island First Nations suggests that water collected near active open-net salmon farms contains four times more pathogens harmful to wild salmon than samples collected near inactive salmon farms.

The study, published in the peer-reviewed journal Scientific Reports, examined environmental DNA to determine the levels of bacteria, fungi and viruses previously shown to be harmful to wild salmon. 

The Pacific Salmon Foundation says researchers collected samples from areas around the Broughton Archipelago near north Vancouver Island, including active and inactive open-net salmon farms. 

"That gives us the confirmation that salmon farms can actually contain and amplify pathogens that can ... therefore affect wild salmon that live in the area," said Emiliano Di Cicco, a researcher with the foundation. 

"We are a strong proponent of moving the farms out of the water in either a closed containment or any type of containment that would protect wild fish from the disposal of what comes out of the farms."

Di Cicco says that, of all the factors affecting salmon populations, including climate change, open-net salmon farms are one risk that can be more easily removed. 

Open-net Atlantic salmon farms are a controversial topic in many coastal B.C. communities.

Some coastal First Nations and environmental groups have opposed open-net salmon farming, saying they are linked to the transfer of disease to wild salmon. 

The federal government has decided to close the province's open-net salmon farms by 2029. 

But the B.C. Salmon Farmers Association says the province could lose up to $1.17 billion in economic activity and 4,560 full-time jobs if open-net salmon farming is no longer allowed.

The association has strongly discredited this latest research, saying the results overestimate the risk of the pathogens' harm to wild salmon. 

Gary Marty, a senior fish pathology consultant for the association, says all animal populations have disease.

"Anywhere we have lots of animals, we will have more disease than anywhere we don't have lots of animals," Mary told CBC News. 

"We also have wild salmon that are migrating sometimes in the millions, and it's likely there's lots of disease near those wild salmon."