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LEWISTON – Three adult coho salmon, the first of a Nez Perce tribe effort to restore a vanished course, have returned to the Lostine River.
The fish, which were among the more than 500,000 smolts released into the river in March 2017, were trapped at a dam near the town of Lostine this week. More fish are on the way.
Prior to the release of smolts last year, about 5,000 people had been implanted with tiny electronic tags allowing them to be detected when they passed by dams on the Snake and Columbia rivers. According to the latest information available, approximately 2,100 fish climbed the fish ladders at the Bonneville Dam on the Columbia River and about 300 crossed the Lower Granite Dam on the Snake River.
Becky Johnson, production manager of the tribe's fisheries division, said there have been no more two adult coho salmon in the Lostine River since 1966. The descent was officially declared extinct in the 1980s.
Johnson said it was difficult to predict how many adult coho salmon estimated on the way could "convert" or get to Lostine this fall. In fact, smolts are the offspring of coho trapped at the Bonneville Dam as they move to much lower rivers in the basin and have not been genetically programmed to travel this long distance.
"Their parents have not traveled 600 miles in eight dams, so I would not expect a huge conversion," she said. "But we do not know what to expect."
All fish trapped at the spillway will be allowed to ascend upstream, where they hope to spawn naturally. Johnson said the tribe's goal was to continue releasing Juvenile Coho salmon from the Lower Columbia in Lostine until the race reaches an annual yield of about 500 adults.
At that time, the tribe will begin to bring the adults returning to a hatchery to spawn with the idea that offspring of successful fish are more likely to produce long-distance swimmers who will also be able to make the trip. .
"If they can ensure their autonomy, we will start by collecting spawners," she said.
The tribe has experience in rebuilding stocks of extinct coho salmon. For more than two decades, the Tribal Fisheries Division released coho in the lower Clearwater River, with modest results. This changed in 2015 with the explosion of the pass and the fishermen were allowed to fish and harvest coho in the Clearwater River for a few years.
The Clearwater Coho Race is fighting again. Like the return of the Steelhead and Chinook salmon, the coho race has been affected by poor ocean conditions in recent years. Johnson said only about 1,200 are expected to return to Clearwater this fall. This is compared to an average of 5,000 over 10 years.
The recovery effort in Lostine is funded by the Mitchell Act and the Pacific Coast Salmon Recovery Fund through the National Oceanic and Atmospheric Administration fisheries.
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