The WDFW said Cooke was complying with its permit by culling 800,000 smolts. Image: WDFW website.

Cooke culls 800,000 fish after ‘exotic’ PRV found

Cooke Aquaculture Pacific has been forced by officials in the US state of Washington to destroy a batch of 800,000 juvenile Atlantic salmon for the second time in a year because they carried an “exotic” strain of Piscine Orthoreovirus (PRV), according to a report in the Seattle Times.

Published Last updated

Although a strain of PRV is found locally, it is different to the one found in the farmed fish, which the Washington Department of Fish and Wildlife (WDFW) considers to be an unacceptable risk to native stocks of Pacific salmon.

According to the Seattle Times, the exotic strain found in Cooke’s latest batch after tests is essentially the same strain of virus found at the Iceland hatchery from which Cooke receives Atlantic salmon eggs.

Under the conditions of its permit, Cooke was required to destroy the fish at its Rochester, Thurston County, hatchery facility. The same thing happened in May, when the WDFW refused Cooke a permit to re-stock sites in Puget Sound because of the exotic strain and 800,000 smolts were culled.

‘Protecting Puget Sound’

“They are complying with the terms of the permit, and we are protecting Puget Sound from this exotic strain,” Amy Windrope, Region 4 director for WDFW, told the newspaper.

Cooke declined to comment to the Times, which also reported that 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 Washington state-based Troutlodge, the world’s leading producer of eyed trout eggs, which is owned by Hendrix Genetics.

Native trout

Earlier this year Washington state legislators voted to phase out non-native finfish open-cage farming, a decision that effectively applied only to Cooke, the sole Atlantic salmon farmer in the state.

The law wouldn’t apply to rainbow trout, which are native to the Pacific Northwest of the US, and a switch to trout production might allow Canadian-owned Cooke to continue making use of its $76 million investment in assets in Washington state.