The beginning
Salmon farming begins in B.C.
This story originally appeared in the Spring 2026 edition of Salmon Steward, the Pacific Salmon Foundation’s print magazine.
PSF advances science, and consultation carries on, leading up to the 2029 ban on open-net pen salmon farms in B.C.
With three critical years left until the ban on open-net pen salmon aquaculture takes effect, the Pacific Salmon Foundation (PSF) is building on more than a decade of peer-reviewed science. By continuing research on risks of pathogen transmission from farmed to wild salmon, PSF is helping shape an evidence-based path forward.
The transition away from open-net pen salmon farming has been years in the making. The federal government initially committed to phasing out the practice in 2019. Five years later, Canada announced that open-net pens will be banned in B.C. by 2029.
This move was celebrated as a win for wild Pacific salmon, which face risks from these underwater net-pens that breed more than just fish. These high-density fish farms can spread parasites and pathogens into the migration paths of wild salmon, as evidenced by dozens of studies.
“The decision to ban open-net pen Atlantic salmon aquaculture really matters for wild Pacific salmon, because it eliminates one of the major threats to wild Pacific salmon that we actually have the power to control,” says Dr. Andrew Bateman, who leads habitat and ecosystem science at PSF.
Since the ban was announced, the federal government has led consultations with key entities and released a draft transition plan, for which PSF provided science-based feedback. The final transition plan, which will outline the next steps to implement the ban, was initially scheduled for release in 2025, but has been delayed.
Current status of open-net pens
Of the roughly 100 open-net pen salmon farms that once operated in B.C., about 45 of those have been closed to date in decisions made either by the government or local First Nations. Roughly 55 salmon farms remain in operation or are licensed to operate in B.C. today. The majority of those exist along the west coast of Vancouver Island or on the Central Coast of B.C.
Keeping wild salmon healthy
For more than a decade, PSF, independent scientists, academic institutions, and First Nations have studied the risks open-net pen salmon farming pose to wild salmon.
Through the growing body of research, three prominent infectious agents of concern have emerged:
- Sea lice: In the Broughton Archipelago, sea lice outbreaks from salmon farms have resulted in reduced survival in pink and coho salmon. Lab research has also shown that sockeye can experience skin erosion, scale loss, and stress from sea lice.
- Tenacibaculum maritimum: The marine bacterium Tenacibaculum maritimum is found globally, but amplified by Atlantic salmon farms in B.C., and presents a substantial risk to sockeye, Chinook, and coho salmon.
- Piscine orthoreovirus: Piscine orthoreovirus (PRV) originated in the Atlantic Ocean and was introduced to B.C. with the advent of salmon farming. PRV is tied to poorer survival of Chinook and coho salmon, and has been linked to disease in Pacific salmon.
Dozens of other infectious agents associated with salmon farms may pose a risk to wild salmon and require further research.
To minimize the risk of these pathogens spreading to wild salmon, PSF has called for the transition of Atlantic salmon aquaculture from open-net pen farms to closed containment — a technique where an impermeable barrier prevents the flow of waste, viruses, and bacteria from entering the marine environment.
“Open-net pen salmon farms are fully open, where anything in the water can flow in or out of the net. Closed containment systems should be truly closed to the transfer of everything, especially infectious agents, which is imperative from the perspective of wild salmon,” explains Dr. Will Bugg, a postdoctoral scientist with PSF.
There’s also an in-between system: semi closed containment. As the name suggests, this hybrid option is partly permeable and was developed to protect farmed salmon from sea lice. However, this method still allows the free flow of materials between farms and the ocean.
“Semi-closed containment, or any containment that allows for the transfer of infectious agents into the external environment, is not a viable solution to mitigate the risks that salmon farms can pose to wild salmon,” says Dr. Bugg. “The Pacific Salmon Foundation supports the move to entirely closed containment salmon farming in British Columbia.”
More science on the way
PSF continues to pursue key science on the issue.
“The more we study, the more we find the risks to wild salmon from open-net pen salmon farming to be real — underscoring the importance of implementing the B.C. ban,” says Dr. Bateman.
Upcoming research will explore new evidence on Tenacibaculum‘s impacts on Chinook salmon and links between Piscine orthoreovirus and a condition known as ‘Heart and Skeletal Muscle Inflammation.’
PSF will continue monitoring wild juvenile salmon this spring in the Discovery Islands as they migrate out to sea, collecting additional data to advance our understanding of the impacts of open-net pen salmon farms on wild Pacific salmon. These monitoring efforts are currently funded through 2028.
