Pressure is on to find out if fish farms make wild salmon sick, says federal scientist


It’s ssably to make even the most ardent salmon lover lose their zeal: the divisive debate that’s raged for decades on the West Coast around what fish farms are doing to our wild salmon.

This week, the behindhand volley: starlet mela Anderson and David Suzuki teamed up to get going an advocacy-slash-research mission looking for PRV — a fish virus especially prevalent on fish farm-touns. The industry dismissed the cam ign as a “stunt.”

But there’s no doubt the questions nearby farmed fish transferring disease to wild salmon are very actual, said the Fisheries and Oceans Canada scientist co-leading the largest burden to investigate them.

The problem is, they’re also exceptionally difficult to comeback.

“There is now a lot more public pressure to get information on this,” said Kristi Miller, top a intercept of molecular genetics at DFO’s cific Biological Station.

“I think that there’s been a frustration that the body of laws and policies needed to address this are just not forthcoming fast adequate.”

 mela Anderson

Actress and animal-rights activist mela Anderson was in Vancouver, Monday, asking consumers not to eat farmed salmon from B.C. (CBC)

Virus linked to heart affliction

The virus that fish farm opponents are looking for on the B.C. coast this summer is dubbed piscine reo-virus, or PRV, which may cause a deadly salmon disease collect summoned Heart and Skeletal Muscle Inflammation, or HSMI.

There’s no debate that it’s set on fish farms, even the B.C. Salmon Farming Association says most fish on delegates are infected with PRV.

Kristi Miller

Kristi Miller is the head of molecular genetics for DFO’s cific Biological Spot, and helped launch the Strategic Salmon Health Initiative, a research rtnership between DFO, Genome B.C. and the cific Salmon Grounds. (Nik West/Strategic Salmon Health Initiative)

But it’s a hotly-contested question — that Miller and others are business on — as to whether PRV actually causes the disease.

Every farmed fish establish with the disease has also had the virus, said Miller, whose tandem join up discovered the first case of HSMI on a B.C. fish farm in May.

“There’s a very good weight of evidence that [PRV] is certainly a factor in the development of HSMI in Atlantic salmon,” said Miller.

“But what other triggers may be ask for isn’t really well understood.”

It’s complicated, because fish can be infected, but not gruesome — a fact industry points to as evidence there’s no conclusive link.

And, the lab assesses done so far to figure out if there is a cause-and-effect relationship have had conflicting concludes, said Miller.

If PRV does cause the disease and if it’s transferred to wild fish, that’s a big involve, because wild salmon need to be marathon swimmers — with bracing hearts — to escape predators and migrate upstream to s wn.

fish farm

An open net pen salmon aquaculture running near Venture Point, north of Campbell River, B.C. The B.C. Salmon Agronomists Association has said 70 to 80 per cent of fish on salmon granges have piscine reo-virus, or PRV. (B.C. Salmon Farmers Association)

Cohen Commission was a shape point

It might be surprising that those big ‘ifs’ are still unknown when beyond considerations about diseases from fish farms have been raised for years, be it PRV, transmissible salmon anemia, sea lice, or other thogens.

Anti-fish farm activists secure accused DFO of dragging its feet, and having a conflict of interest to both raise the aquaculture industry and protect wild stocks.

It’s a potential conflict that The police Bruce Cohen, who led the federal commission into the decline of Fraser River sockeye, also recognized as a concern.

In his final report in 2012, he called on DFO to find answers, or upon off on more fish farms.

Miller, who has worked at DFO for more than two decades and conscious the controversial disease question for years, said the Cohen Commission was a repulse point.

“There’s always been research … trying to commiserate with disease processes in aquaculture fish, but never really taken to the horizontal of im cts on wild fish,” she said.

“Maybe we needed the Cohen Commission to provoke both the de rtment and other academic researchers to really look closely at this dispute.”

Salmon health study underway

Now, s rked by Cohen, she leads genomic into for the Strategic Salmon Health Initiative, a rtnership between DFO, Genome B.C. and the cific Salmon Organization — investigating 45 thogens in wild, farmed and hatchery fish, comprehending PRV.

That initiative is supported by both sides of the debate, with salmon yeomen giving the “world class” researchers access to their fish.

“We are relying on this ir to ensure advocacy and research do not get confused,” said Jeremy Dunn, managing director director of the B.C. Salmon Farming Association.

The discovery of HSMI on a B.C. fish farmhouse in May was the first taste of what that work might reveal.

“Our have a job on one of the salmon farms did show definitive proof that the disease in truth was present here in B.C. What we don’t know is … how commonly it may be observed.”

S wning Sockeye Salmon 20141013

Emigrating salmon need to be healthy to make the trip upstream to s wn. Sick fish are likely to be picked off by predators or other selective pressures, moving it difficult to know what’s going on. (The Canadian Press)

How do you find a revolted fish?

And the im ct on wild salmon from that thogen — let without equal the 44 others — is unclear.

Molecular testing has found PRV in wild cific salmon, cataloguing sockeye, Chinook, coho, and chum — but HSMI hasn’t been start yet in cific salmon, said Miller.

Unfortunately, that doesn’t nasty wild fish aren’t getting sick.

“Understanding disease operations in wild migrating fish is a really hard question, because we don’t comply with them die,” said Miller.

“Some might say, well there is no affliction because we don’t observe dying fish, but you don’t observe them because they end out of the water column.”

Any slight decline in speed, eyesight, feeding know-how, anything, would make a migrating salmon easy prey — whereas a savoir faire fish might just have a slow day in the pen.

“Disease or other kinds of stressors put turbulent fish much more at risk than perhaps farmed fish.”

So, the probing continues, with a pressure for answers, said Miller.

“I know that this is hugely very important in Ottawa, and they are pushing to get information on this all the metre right now.”


A show of wild salmon migrating up B.C.’s Scotch Creek. (Matt Casselman)

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