Thousands of Atlantic salmon escape fish farm near Victoria after nets damaged

Thousands of Atlantic salmon have escaped into Pacific waters east of Victoria after nets containing an estimated 305,000 fish were damaged at a U.S. fish farm in the San Juan Islands on Saturday.

The company, Cooke Aquaculture, blamed "exceptionally high tides and currents coinciding with this week's solar eclipse" for the failure of the net pen near Cypress Island.

The nets "broke loose" from their anchor Saturday afternoon, said Ron Warren, assistant director of the fish program for the Washington Department of Fish & Wildlife.

Warren said strong tidal flows — which are tied to the lunar cycles, not the eclipse itself — could be a factor in the damage, along with the amount of fish in the pens, which he estimated at more than 1.3-million kilograms.

"A lot of fish, a lot of weight … certainly could have aided in the compromise of the structure itself."

However, while the tides and tidal currents in the area over the past week were "fairly high and fast," they were not projected to be any stronger than they had been May, June or July, said Greg Dusek, a senior scientist with the U.S. National Oceanographic and Atmospheric Administration in a statement.

"The eclipse itself would have nothing to do with this," Dusek wrote.

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Unknown number of fish

In a statement on Monday, Cooke Aquaculture said it didn't know how many fish escaped, but estimated it was "several thousand." No company official was available for an interview on Tuesday.

Warren pinned early estimates at 4,000 to 5,000, but said the company still on Tuesday has not been able to anchor the net pens due to strong tidal currents.

Atlantic salmon are not native to Pacific waters, but are a major aquaculture species in Washington state and British Columbia.

Their presence in fish farms — and potential to escape from net cages — has been a hotly debated part of the West Coast fish farm industry for years, due to concerns about whether the foreign fish could cause harm to the five wild species of Pacific salmon.

Concern over Atlantic escapes

The concern with an introduced species, like Atlantic salmon on the West Coast, is whether it could become invasive — not just present, but damaging to the native ecology.

Washington officials put Atlantic salmon on their list of invasive species that are not regulated, but are considered "highly threatening" over worries they could harm native fish stocks through competition, predation or disease transfer.

"Atlantic salmon, regardless of whether they have successful spawning, they're competing [against wild fish] for the food source that's there," said Warren, noting threatened wild populations of chinook and steelhead trout in the area.

"That's a concern for us and we're going to be monitoring the best we can."

The Washington Department of Fish & Wildlife is encouraging recreational and commercial fishers to catch Atlantic salmon if they find them, and even changed the rules to allow commercial fishers to sell the fish legally, due to the size of the escape.

'Potentially invasive species'

In Canada, Fisheries and Oceans Canada monitors for escaped Atlantic salmon, according to a statement, but doesn't use terms like "invasive" or describe them as any particular threat to local fish.

University of Victoria ecologist John Volpe said the problem is it is unknown what the impacts are.

"In my mind it's really a dereliction of duty in terms of the regulating mechanisms in this country to not have an answer to that question, given that our coast of British Columbia here is literally awash in these potentially invasive species," he said.

"Nothing good is going to come of these releases, and the ... magnitude of negative impacts might be very, very severe."

Volpe, who has found evidence of Atlantic salmon spawning in B.C. waters, said there has been a "chill" on researching the topic in Canada.

A statement from Fisheries and Oceans Canada said the department was aware of the incident, and anyone who suspects they've caught an Atlantic salmon in B.C. waters should report it to the Atlantic Salmon Watch Program at 1-800-811-6010.  

A spokeswoman said Tuesday that the agency's program monitoring Atlantic salmon sightings had no new reports this week.

A 2015 report by the department looking for Atlantic salmon found none in the Vancouver Island streams that were surveyed.