About 115,000 fall chinook salmon have hitched a ride to Hells Canyon as part of a Nez Perce tribal project to rebuild a historic run.
The chinook were drafted from Washington state’s Lyons Ferry Fish Hatchery, which biologists believe holds the truest remnants of the Snake River run.
Only a few hundred wild fish still return to the Snake to spawn each fall, a bare whisper of the thousands that once dug nests in the river’s gravel.
The Washington Fish and Wildlife Department’s efforts to keep the fish run at Lyons Ferry have been paying off, enough so that the tribe’s plan could proceed this year.
Fifteen fiberglass tanks were located at Pittsburg Landing, the takeout spot for boaters and floaters in the canyon.
The fish will camp out there for another two weeks before tribal biologists open the tanks.
At Lyons Ferry, between Little Goose and Lower Monumental Dams on the Snake and nearly 100 miles downriver, the return rate averages about three adults per thousand smolts.
The little salmon are nearly 1-1/2 years old. Once they are released April 15, the tank farm will be torn down and stored for a replay next year, according to plans.
The experiment is scheduled to last three years. Problems prevented the original target release time of mid-March.
Acclimation sites, as the tanks or more typical earthen ponds are known, are standard operations by U.S. Fish and Wildlife and other agencies.
An agreement with the National Marine Fisheries Service required the fish to be spawned in hatchery raceways and their young reared there until they were big enough to be released upstream from the dam.
The plan was intended to keep hatchery-reared salmon from mixing with wild fall chinook in the Snake.