The collapse of a marine net pen holding more than 300,000 farmed Atlantic salmon on the Washington State coast has renewed a debate about the safety of fish farms and their potential impact on the region's ecosystem, although state officials caution there is no evidence the incident poses a threat to wild stocks.
The salmon were released over the weekend at a Cooke Aquaculture facility located about 40 kilometres east of Vancouver Island's southern tip. The company blamed the failure on especially high tides coinciding with Monday's solar eclipse.
It is still not clear just how many fish were released. In Canadian waters, there has been one unconfirmed report of possible Atlantic salmon, the Department of Fisheries and Oceans said.
Ron Warren, who heads the Washington Department of Fish and Wildlife's fish program, said there's no evidence the escaped fish pose a threat to native populations, through disease or crossbreeding with Pacific salmon.
Still, he said the state wants to protect native fish species and have urged anglers to catch as many escaped salmon, some up to 10 pounds, as possible.
Jill Rolland, who directs the U.S. Geological Survey's Western Fisheries Research Center in Seattle, said she's not concerned that the escaped fish have any pathogens that will spread to wild fish.
"We have a very strong regulatory environment to ensure that these fish are under veterinary care," she said.
Critics say the recent fish escape highlights potential risks of open-sea fish farming. They worry about water pollution from fish feed and the potential for farmed fish to spread diseases and parasites to wild fish.
"These are open-net pens. They're not isolated from surrounding environment," said Chris Wilke, executive director of the Puget Soundkeeper Alliance, which opposes the project.
British Columbia and Washington each have the largest marine fin-fish aquaculture industries in Canada and the United States, respectively. B.C. produced about 93,000 tonnes of farmed salmon worth $470-million in 2015, according to statistics compiled by DFO. In Washington, the industry produces about 7,700 tonnes of Atlantic salmon each year, according to the state.
While salmon farms have operated for decades in both Washington and British Columbia, they still remain controversial in a region where wild salmon reigns supreme.
Alaska has banned commercial fin-fish aquaculture. Several counties in Washington, such as Whatcom County, have moved to limit commercial fin-fish aquaculture.
In British Columbia, opponents of the industry have repeatedly warned that open-water fish farms pose a risk to wild Pacific salmon, and the industry came under scrutiny during a federal public inquiry launched in the wake of the devastating collapse of salmon stocks along the Fraser River during the 2009 season. The head of the commission, retired judge Bruce Cohen, was unable to find a "smoking gun" to explain what happened, but he did urge the federal government to take steps to limit the impact of fish farms.
In the wake of the stock collapse, Ottawa imposed a temporary moratorium on new fish farms that has since been lifted.
DFO tracks reports of Atlantic salmon – considered an invasive species – off the West Coast. The department said it received a report on Wednesday about a large school of fish swimming near the surface, but it couldn't confirm if they were Atlantic salmon or if they were related to the Cooke Aquaculture fish farm.
Before this week, the department hadn't received any reports of Atlantic salmon since 2014, when one case was reported.
Michael Rust, science adviser with the U.S. National Oceanic and Atmospheric Administration's aquaculture office, said farmed salmon tend to be domesticated, raised on feed and not used to catching fish or escaping predators. Farmed salmon are more likely to be prey than predator, he said.
He and others note that advances in science and technology have improved fish-farming practices in the United States over the decades and aquaculture operations must meet strict regulations.
The release at Cooke Aquaculture's facility comes as the company is proposing a new expanded commercial facility in the Strait of Juan de Fuca in Washington State.
Canada-based Cooke, which operates five salmon farms in Washington that it acquired last year, would build 14 floating circular net pens about 1.6 kilometres offshore. It would move current operations from Port Angeles Harbour and increase production by 20 per cent. The project is in the permitting phase.
Cooke blamed high tides and currents coinciding with Monday's solar eclipse for the failure over the weekend at its farm off Cypress Island in Skagit County, Wash.
"The ongoing tides were a huge challenge," said Nell Halse, a Cooke spokeswoman. She said the company called in experts last month to stabilize the salmon farm during high tides, although no fish escaped then. "We put our best expertise to stabilizing this farm and we had no reason to believe that it would have collapsed on Sunday."