Fish Farmer Destroys 800,000 Juvenile Atlantic Salmon Due to Disease; Second Purge in Past Year


For the second time, Cooke Aquaculture Pacific has destroyed 800,000 juvenile Atlantic salmon after testing required by the Washington Department of Fish and Wildlife (WDFW) determined the fish were infected with an exotic strain of Piscine Orthoreovirus (PRV.)

The strain is essentially the same strain of virus found at the Iceland hatchery from which Cooke receives Atlantic salmon eggs.

Cooke had a similar problem last May. Tests on the most current batch recently came back, said Amy Windrope, Region 4 director for WDFW. Two of Cooke's last three batches of Atlantic salmon in the past year have tested positive for PRV, Windrope said. The third was clean.

The department considers the exotic strain of PRV to be an unacceptable risk to native stocks of Pacific salmon. Under the conditions of its permit, Cooke was required to destroy the fish at its Rochester, Thurston County, hatchery facility.

The fish were in quarantine prior to their destruction and the water they swam in at the hatchery was disinfected prior to discharge.

"They are complying with the terms of the permit, and we are protecting Puget Sound from this exotic strain," Windrope said.

Cooke declined to comment on the findings, Joel Richardson, vice president of public relations for Cooke Aquaculture wrote in an email to The Seattle Times.

The WDFW is processing a permit from Cooke to move about 500,000 rainbow-trout eggs to its Rochester hatchery by early January. The eggs would be supplied by Troutlodge, a vendor in Washington.

Ken Warheit, director of fish health for the state of Washington, said the state has not tested Cooke's adult Atlantic salmon in its pens for PRV because the state is updating its rules. Testing of adults may take place in the spring, he said.

Atlantic-salmon farming was a little-noticed business in Washington until Cooke acquired its farms in the state and in August 2017 caused a spill of about 260,000 Atlantic salmon from its Cypress Island farm because of inadequate maintenance of its nets, three state agencies found after an intensive investigation of the spill.

The spill and state findings led the Washington state Legislature last session to enact a gradual phaseout of net-pen farming of exotic species in Washington waters by 2025, including Atlantic salmon.