KETCHIKAN -- Commercial fishermen in Southeast Alaska have caught more than 20 Atlantic salmon, raising concerns that the farmed salmon will spread disease to wild species.
All the Atlantic salmon were caught south of Ketchikan - some in the Tree Point area, said Phil Doherty, an Alaska Department of Fish and Game biologist for commercial fishing.
"This is a real problem," Doherty said, pointing to the six, 10- to 12-pound Atlantic salmon spread out in the conference room Friday at Ketchikan's Fish and Game office.
Not only are the Atlantic salmon a threat to Pacific salmon because of competition for food in the open ocean, but they also carry a threat of disease.
"The big problems are the diseases that these imported fish bring; from viruses to external parasites," he said.
Last week, more than 35,000 farmed Atlantic salmon escaped from a pen in Johnstone Strait, off the northern tip of Vancouver Island.
"Whether they are a part of the 35,000 that spilled out of that farm a few days ago, I don't know," Doherty said. "It seems like a lot of water to cover in such a short time, but they are showing up in Southeast."
It was once believed that Atlantic salmon would not venture into freshwater, but several pen-reared salmon have been found in fresh water streams. In 1998, an Atlantic salmon was recovered north of Ketchikan at Ward Creek. The Atlantic salmon was sexually mature and had a mate that eluded capture.
"If there's one here and there are thousands of freshwater streams in Southeast Alaska, it's very likely there are more in some of those streams," Doherty said.
Unlike traditional hatcheries where the fish are released to grow in the seas, farmed Atlantic salmon are supposed to spend their entire life in captivity. Atlantic salmon, of which there is only one species compared to five species in the Pacific Northwest, resemble steelhead trout.
Atlantic salmon also stay alive after spawning, unlike Pacific salmon that die, Doherty said.
Expansion of British Columbia's fish farm industry has been halted since 1995 when a moratorium was established. Doherty said Fish and Game hopes that the moratorium is not lifted.
"We don't want to see fish farms as close as Prince Rupert, (British Columbia)," he said.
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