Atlantic salmon introduce disease to native salmon

When more than 260,000 Atlantic salmon spilled from a failed net pen into Puget Sound, they carried a potentially devastating virus to native salmon species.

One hundred percent of the 19 tested salmon, which escaped from Cooke Aquaculture’s fish farm off the shore of Cypress Island in August 2017, are positive for piscine reovirus, or PRV, a non-native virus to Pacific salmon.

“This strain has never been seen before in the entire Pacific coast,” said Kurt Beardslee, executive director of Wild Fish Conservancy. “This is not a good sign.”

Atlantic salmon are native to the Atlantic Ocean and farmed in Washington for human consumption. Pacific salmon, native to the West Coast, are threatened by this virus. Beardslee likened the spread of the sickness to the smallpox outbreak that killed the Native Americans on the East Coast when European settlers arrived in the 1600s.

“I use this example because it’s something we all know about,” he said, explaining that just as the Native Americans had a lower immunity to smallpox, the Pacific salmon’s immune systems are unprepared for this new virus.

On Aug. 9 on Orcas, Beardslee lectured about how the Atlantic salmon virus is affecting the native species of the Salish Sea. He spoke the previous evening on San Juan Island. Beardslee represents both the Wild Fish Conservancy and Our Sound, Our Salmon, a citizen group effort to rid Puget Sound of Atlantic salmon fish farming.

Beardslee explained that Atlantic salmon evolved with PRV and have built up an immunity to the virus, an advantage that the Pacific salmon do not possess. Though the domesticated salmon are asymptomatic, the virus ruptures the Pacific salmon’s red blood cells, which makes fish unable to use their muscles effectively.

“A very, very different response, so very, very different physical reaction that the fish have to it,” Beardslee said. “If your muscles aren’t working, and you’re out in nature – I don’t care if you’re in the Serengeti or if you’re in Puget Sound – you’re going to be someone else’s dinner. … It’s tough out there, and you’ve got to be at your best.”

According to Beardslee, all of the salmon that Cooke Aquaculture houses in its Puget Sound net pens come previously infected with PRV. He said he believes that the eggs are pre-infected with the virus to help boost the fish’s immunity to Infectious Hematopoietic Necrosis Virus, an illness that Pacific salmon carry.

“That’s really scary,” said Beardslee. “They’re using this as a pharmaceutical – at least I believe they are – I might be wrong. They’re using their own natural immune systems and their own natural viruses to protect them from non-native viruses, but it’s spreading out to our fish and causing our fish more harm. Again, that’s total speculation, but you can connect the dots.”

National Marine Fisheries Service and the Environmental Protection Agency researched the net pens in 2008 and resolved that it was impossible that native juvenile salmon could be negatively impacted, explained Beardslee. The Wild Fish Conservancy countered the agencies’ findings in a lawsuit.

“In 2011, they came back and said, ‘We thought about it, but no, it’s still not likely to have an adverse effect,” Beardslee said.

The following year, the largest IHNV outbreak along the Washington coast occurred among farmed Atlantic salmon, said Beardslee. In May 2012, three Puget Sound and three British Columbia Atlantic salmon net pens were infected with the virus. In total, approximately 2 million pounds of Atlantic salmon were contaminated and lost to the virus.

“No monitoring was done because the industry wouldn’t allow it to happen,” Beardslee said, adding that government agencies have not acknowledged that the 2012 outbreak happened. “We have lots of these apparent regulations and monitoring occurring. This is the bottom line. It isn’t what it should be, and they’re not being very responsible.”

Cooke Aquaculture purchased the Washington state net pens in 2016. At the time, there were three pen facilities off the shore of Cypress Island, one off of Hope Island at the mouth of the Skagit River, two off the coast of Port Angeles and three south of Bainbridge Island.

“This company was so big. It had the ability to expand aquaculture big time in Puget Sound,” Beardslee said. “And they publically were saying that they wanted to expand aquaculture so there would be no need to import from Chile anymore. Basically, Puget Sound would be the new Chile.”

Following the August 2017 net pen collapse, the Washington Department of Natural Resources investigated the remaining pens and revoked the lease for the failed facility as well as the other two Cypress pens and the Port Angeles pens. Then, in March, Gov. Jay Inslee signed House Bill 2957 into law, banning fish farming in the state of Washington and terminating all existing farm leases by 2022. The state also denied permits to Cooke Aquaculture to install a new pen facility outside of Port Angeles.

“Part of the fight is over, but another part is not over. … That was the largest removal of Atlantic salmon pens in the world,” Beardslee said. “We were getting emails from Scotland, Ireland, Canada and Iceland. Everybody was watching what you guys [in Washington] did. It was phenomenal, you should be very proud.”

In the four remaining years of Cooke’s net pen lease, however, PRV can continue to spread and cause irreparable damage to dwindling native salmon populations, Beardslee warned. Juvenile salmon leaving the state’s hatcheries are the most vulnerable. However, PRV has been found in juvenile fish just released from hatcheries, leading scientists to believe that the virus is also hereditary, explained Beardslee.

Beardslee is concerned that the juvenile Pacific salmon that tested positive for PRV have not been exposed to the net pens and therefore must be contracting the virus from their parents. It is possible that the hatchery could be a spawning ground for PRV.

“We have to sample all of our hatcheries, the science is clear that this could be a major threat. We have to make sure that our hatcheries are not generators of this virus,” said Beardslee.

Beardslee explained that the Wild Fish Conservancy has filed a lawsuit against Cooke Aquaculture for violating the nation’s Clean Water Act.

“Each one of those fish is considered a violation of the clean water in tens of thousands of dollars. We’re filing 260,000 violations of the Clean Water Act. So yeah, we’re on their case,” Beardslee said. “Close to 30 years, all the attorneys we’ve had have donated their time. … They do it because we bring good cases, we have really good scientists and we win. We win all the time. So I’m pretty sure we’re going to win this one, too.”

He explained that testing needs to be conducted on salmon still in net pens. If the salmon test positive for PRV, the fish and their contaminated pens need to be removed for the safety of native fish. According to Beardslee, more than 1 million Atlantic salmon remain in fish farms around Puget Sound.

“That’s how many we’ve got to get rid of,” he said.

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