The escape of thousands of farmed salmon on the south coast of Newfoundland is a significant concern, as is the lack of public notification about the incident, the Atlantic Salmon Federation says.

Cooke Aquaculture confirmed Monday that over the course of four days last week between 2,000 and 3,000 salmon escaped from the company's fish farm in Hermitage Bay.

The company said it alerted the province's department of Fisheries and Land Resources, as well as the federal Department of Fisheries and Oceans, as soon as it saw the breech.

But the public wasn't made aware of the escaped fish until locals began noticing farmed salmon in the ocean, Atlantic Salmon Federation coordinator Steve Sutton told CBC Radio's The Broadcast.

"It raises the question of how many times have other escapes happened where nobody has seen the fish and nobody knows the difference," Sutton said.

"This is a public resource, public waters. They should be required to report these things to the public as soon as they have the information."

Cooke, DFO attempting to recapture fish

Cooke Aquaculture said it is working with DFO to recapture the escaped salmon and has three nets out at different locations around the farm site. DFO confirmed that its officers have spotted farmed salmon in the wild and are working with the company to recapture the fish.

Recapturing those fish, especially days after they escaped, is "virtually impossible," Sutton said.

Up to 3,000 farmed salmon escaped from the Cook Aquaculture salmon farm in Hermitage Bay. (Mark Quinn/CBC)

"If fish didn't move they wouldn't need to be in cages in the first place," he said.

"So those fish, most of them have dispersed who knows where."

The primary concern is that the escaped salmon will mate with wild salmon, which Sutton said will "pollute the genetics" and harm a salmon population already assessed as threatened.

"They make the wild fish, the offspring of those fish, less adapted to the local environment," he said.

Interbreeding has already happened between wild and farmed salmon in the province. A 2016 Department of Fisheries and Oceans study found that farmed salmon had mated with wild salmon in 17 of the 18 rivers surveyed on the island's south coast.

"This is just what that population on the south coast doesn't need at this time," Sutton said.

Escape caused by human error

The escape of the fish was the result of human error, according to Joel Richardson, Cooke Aquaculture's vice president of public relations.

Nets were being repaired, and rope came undone in two places on a net extension installed last week, Richardson told The Broadcast on Tuesday.

The result was two holes in the net, about three-to-five feet long, through which the farmed fish escaped.

Washington State banned Atlantic salmon farming in state waters after tens of thousands of fish escaped a Cooke Aquaculture fish farm. (Beau Garreau)

There are financial consequences to losing fish, but Sutton believes there should be additional penalties to create incentive for aquaculture companies to ensure fish are in their cages.

He pointed to a case in Washington in the United States, where 250,000 salmon escaped a Cooke Aquaculture farm. The state is now moving away from aquaculture.

"That's not likely to happen in Newfoundland, but at least we're seeing other jurisdictions take steps to make sure there are consequences for companies when they lose fish, whether it's through human error or otherwise," Sutton said.

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