Piscine reovirus in puget sound
Escaped, farmed Atlantic salmon in Puget Sound have tested positive for Piscine Reovirus (PRV), and the strain of that virus is of Norwegian origin.
In February 2018, Wild Fish Conservancy Northwest announced test results from an independent laboratory at the University of Prince Edward Island. WFC contracted the lab to test 57 tissue samples taken from 19 farmed Atlantic salmon that escaped from a Cypress Island net pen in August 2017. The 19 fish were donated to WFC by commercial, tribal, and recreational fishermen, and were caught in the Strait of Juan de Fuca, the site of the Cypress Island escape, and 50 miles upstream the Skagit River.
The independent lab results concluded that all 19 fish were infected with Piscine Orthoreovirus (PRV), a highly contagious and potentially debilitating salmonid disease.
The results corroborate a recently released Washington state agency investigative report detailing their own findings of PRV-positive Atlantic salmon originating from Cooke Aquaculture’s Cypress Island net pen facility. Washington Department of Fish and Wildlife tested 4 Atlantic salmon for PRV, and all four came back positive.
The lab work from Prince Edward Island presented another stunning revelation, finding the strain of PRV present in the escaped fish to be of Norwegian origin. This discovery raises immediate concerns as to whether Cooke Aquaculture is placing previously-infected Atlantic salmon into their open-water net pens.
When it comes to the impacts of PRV on wild salmon and steelhead, Washington state agencies need to take a measured and precautionary approach. In Puget Sound, wild Pacific salmon and steelhead find themselves at considerable risk, with several species endangered and many surviving at only a fraction of their historical abundance. Even a small amount of risk from the spread of PRV has the potential to bring about disastrous consequences to already imperiled wild salmon and steelhead. Due to this concern, a measured and precautionary approach dictates that state agencies must err heavily on the side of caution.
The burden of proof that PRV does not cause harm to wild fish does not rest on wild fish. The burden of proof, rather, lies squarely with the Atlantic salmon net pen industry and regulatory state agencies.
Here's what science says about PRV:
Science says there is a high likelihood PRV will transmit from farmed salmon to wild salmon. PRV survives well in sea water, and is known to spread out long distances from farms. The spread of PRV from farmed Atlantic salmon to sockeye salmon has been documented, and a 2017 BC study demonstrated that significantly more wild salmon were infected with PRV if they had been exposed to salmon farms than if they were located far away.
Science says that PRV is the cause of HSMI, a lethal salmonid disease. HSMI causes a crippling onset of symptoms in salmonids, symptoms that would either kill or render a wild fish incapable of surviving in natural conditions. The causal relationship between PRV and HSMI was heavily debated in the scientific community until a 2017 Norwegian study, in which a pure strain of PRV was injected directly into an Atlantic salmon and subsequently tested positive for HSMI.
Science says that even without the occurrence of HSMI, PRV can negatively impact a salmon’s ability to compete and survive in the wild. As PRV builds up in a salmon’s red blood cells, the virus may reduce the amount of oxygen cells can transport to the fish’s muscles, lowering the fish’s performance. For a wild fish, reduced performance means a reduced ability to capture prey, evade predators, and swim upriver to spawn.
Considering the multitude of scientific studies that demonstrate PRV from open-water pens will likely spread to and harm wild fish, the Our Sound, Our Salmon campaign is deeply disturbed by the disease’s apparent ubiquity among escaped Atlantic salmon in Puget Sound. Even more troubling is the possibility of the virus being imported into public waters from an outside source.
In standing firm on our concern over the impacts of PRV to wild Pacific salmon, Our Sound, Our Salmon calls on WDFW and other state agencies to accomplish the following:
1. Stop all restocking of Atlantic salmon net pens until thorough testing has proven the Atlantic salmon hatchery is not planting PRV infected fish.
2. Immediately test all Atlantic salmon net pens in Puget Sound for PRV.
3. Remove all PRV-infected Atlantic salmon from Puget Sound net pens.
4. Immediately disinfect facilities showing any trace of PRV.
These actions are essential to ensure that PRV-infected fish are not being planted into public waters and that Atlantic salmon raised in net pens are not amplifying the virus and spreading it in the public’s waters where it places our native salmon at risk.
Piscine reovirus in British columbia
Members of the 'Namgis First Nation stand in protest of a ship transferring one million Atlantic salmon smolts to Marine Harvest's Swanson Island Farm. Days earlier, the Canadian Federal Court dismissed the First Nation's court bid to block the restocking of the open-net salmon farm in its traditional territories off northern Vancouver Island.
Read about it here.