A 2018 file photo shows a fish farm in the Clio Channel, northwest of Campbell River.

Virus found among Atlantic salmon ‘poses minimal risk’ to Fraser River sockeye – DFO

Findings released after judge overturns DFO policy allowing transfer of fish without PRV screening

Fisheries and Oceans Canada says that a virus found among farmed Atlantic salmon in the Discovery Islands “poses minimal risk” to Fraser River sockeye salmon, even though much uncertainty remains about the pathogen and how it spreads.

Members of an expert committee briefed reporters on Thursday about piscine orthoreovirus, or PRV. The pathogen made headlines earlier this week when a Federal Court judge overturned a Fisheries and Oceans Canada (DFO) policy allowing young salmon to enter open-net pens without first being screened for the virus.

But scientists on Thursday’s conference call described the risks posed by PRV to Fraser River sockeye as very low.

“There is currently no evidence to suggest that PRV-1 causes disease and mortality in sockeye salmon,” said Gilles Olivier, one of the co-chairs of the peer-review committee.

READ MORE: Alexandra Morton, ‘Namgis First Nation win Federal Court ruling

PRV comes from Norway, and has caused disease there for a number of years, but the virus in B.C. has “lower genetic variability” and is less harmful in B.C.’s farmed Atlantic salmon, he said.

“It doesn’t seem to have the same effect in our Atlantic salmon here in B.C., on the West Coast, (as) it does in Norway,” said Olivier, a former DFO aquatic health official who is now retired.

Research shows that even high viral loads of the B.C. strain of PRV in juvenile Atlantic and sockeye salmon don’t cause mortality, he said.

Data from the review also shows the virus is highly prevalent among Atlantic salmon in net-pen farms and among chinook salmon throughout the Pacific Northwest.

“It has a wide geographic distribution among wild Pacific salmon in B.C., Alaska and Washington, but a lower prevalence than (among) farmed salmon,” Olivier said.

He said virus can’t be cultured, meaning scientists rely on special molecular tools and methods to detect it.

READ MORE: Cermaq says experimental ‘closed-containment’ fish farm coming to Canadian waters

“It’s not easy to work with this virus,” he said.

Much remains unknown about how the virus behaves in B.C. coastal waters, said Dr. Craig Stephen, another co-chair of the review committee.

A high level of uncertainty remains due to “data gaps around things like what’s the concentration of the virus in the water… how well does the virus survive,” he said. “The usual exposure models couldn’t be done.”

Stephen is CEO of the Canadian Wildlife Health Cooperative and a professor at the Western College of Veterinary Medicine.

The 33-person peer-review committee included 15 participants from DFO. Other members came from environmental and Indigenous groups, academia and the aquaculture industry, along with other government departments, according to a DFO news release.

READ MORE: Federal officials showcase ‘health audit’ at fish farm northeast of Campbell River

The committee met for three days in Vancouver last month to review evidence related to the spread of PRV from farmed Atlantic salmon in the Discovery Islands to Fraser River sockeye, said Jay Parsons, a senior DFO official.

No data from the review process was released to reporters. DFO said that “a full report on the peer-review findings” will be published on the Canadian Science Advisory Secretariat’s website in late spring, following a final review by committee members.

The PRV review was the sixth in a series of 10 risk assessments about the spread of pathogens from farmed salmon in the Discovery Islands area, Parsons said.

The risk assessments are part of a response to a federal inquiry into declining stocks of Fraser River sockeye salmon led by commissioner Bruce Cohen. The Cohen Commission’s report was released in 2012.

Last year, a DFO-led study found that that PRV causes the cells of wild chinook salmon to burst, leading to “liver and kidney damage, anemia and death,” according to Ecojustice, an environmental law charity.

On Monday, the Federal Court of Canada overturned a policy allowing young salmon to be transferred into ocean-based fish farms without first being screened for the virus. This followed lawsuits by ‘Namgis First Nation and by biologist Alexandra Morton, an outspoken critic of open-net fish farms.

Justice Cecily Strickland found that DFO’s threshold for acceptable harm to wild salmon was too high and that its policy didn’t comply with the precautionary principle. The court also found that DFO breached its duty to consult ‘Namgis First Nation about PRV.

Strickland gave the federal government four months to review the policy. DFO declined to comment about its plans during Thursday’s conference call.

Like us on Facebook and follow us on Twitter

Just Posted

Warren Goulding column: Letter to the editor was unfair

I’m always impressed with the volume of letters to the editor that… Continue reading

Sarah Simpson Column: It took two months but the cat came back

The column before last, I mentioned that a cat who’d gone missing… Continue reading

Bulldog from Chemainus will be a Wildcat next season

Hawthorne grateful for the chance to play Div. 1 in the U.S. after his BCHL development

T.W. Paterson column: Forbidden Plateau’s lost gold nuggets

“Time and time again the young men scoured the hills…”

North Cowichan will look at hiring staff person to deal with climate change

Coun. Kate Marsh makes motion for a report on issue

VIDEO: Iconic ‘snow cone’ takes shape at B.C. park near Clearwater

Snow cone forming at Wells Gray Provincial Park one that would make Disney’s Queen Elsa proud

Coming up in Cowichan: Bowl for Kids; Leaders of Tomorrow

Bowl for Kids Sake coming up in Cowichan Valley on March 3… Continue reading

A ‘warm embrace’ for grieving parents at funeral of seven young fire victims

Mourners offered love and support to Kawthar Barho, mother of seven children

Indigenous leaders, politicians say Trans Mountain report flawed

The National Energy Board has endorsed an expansion of the Trans Mountain pipeline a second time

UPDATE: Reports of rashes prompt closure of all Harrison Hot Springs pools

Public pool available after Fraser Health shut down all five mineral pools until further notice

Legislation to protect B.C. farmland comes into effect

Regulations enhance food security, encourage long-term farming

Have you heard the legend of Shuswaggi, the Shuswap Lake monster?

Witness accounts as old as 1904, and as recent as 2018, place a creature in the lake’s depths

Credit card fraud steals $50,000 from Victoria businesses: police

Crime Reduction Unit investigating several frauds costing several businesses over $50,000

UPDATE: B.C. ticket holder winner of $25.9-million Lotto Max jackpot

Next draw set for Mar. 1 with an estimated jackpot of $10 million

Most Read