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Methow Valley News September 16, 1999 Endangered Species Coverage Hatchery workers optimistic about spring Chinook returns By John Hanron Hatchery technicians are expressing optimism about the strong return of spring Chinook salmon that have returned to the upper Columbia to spawn. Methow Salmon Hatchery manager Bob Jateff said he is hopeful about the number of three-year-old hatchery-raised Chinook that have been taken at Wells Dam as they made their way up the Columbia River. "That’s pretty good," he said. "I think that’s something to be encouraged about, that survival rate." He said the returning three-year-olds represent about one-half to 1 percent of the 1995 brood of spring Chinook from the state and national hatcheries in Winthrop and released in the Twisp, Chewuch and Methow rivers. Crews at Wells Dam began collecting the returning salmon in early May, trucking them to the Winthrop Hatchery in a tank truck. Jateff said 390 adults were collected at Wells, about two thirds of the total returning population. The rest were allowed to pass through the fish ladders at Wells to proceed up into the Methow watershed on their own power. The returning salmonids were a mix of hatchery-raised fish—which have a clipped adipose fin—and wild Chinook. Once the fish arrive at the hatchery, workers monitor them, and when they exhibit signs of being ready to spawn, they kill the fish, slitting open their bellies and pouring out the eggs or sperm. After checking the information encoded on the wires embedded in the fishes’ snout to determine the age and rearing location of the fish, they fertilize the eggs in a bucket. The carcasses of the salmon are frozen, and given to volunteers from the Methow Valley Fly Fishers Club, who return the frozen carcasses to various points along the Methow watershed. The dead fish will break down, providing nourishment for the other young salmon, steelhead and trout in the river’s food chain. The process mirrors the natural cycle, in which salmon die after spawning, their bodies decaying in the river to feed the living fish. Meanwhile, the fertilized eggs are incubated and the young salmon are reared in the hatchery for about a year and a half. Then, depending on where the eggs originated, the four-to-five-inch fish are transported to one of two rearing ponds the hatchery operates, near Boulder Creek on the Chewuch River or on the Twisp River above Elbow Coulee. The intention is to have the fish acclimatize to the particular water, imprinting the information in the fish’s brain to help guide it back when the time comes to return to the river. The fish will stay in the acclimatization pond for four to six weeks, when they are released into the river. Jateff said Monday (Sept. 13) that the hatchery had collected about 475,000 spring Chinook eggs this year, to be split evenly between the state hatchery and the national hatchery. The survival rate until the time the year-and-a-half-old fish are released into the holding ponds is upwards of 90 percent. Typically a spring Chinook will spend six to 18 months in fresh water, Jateff said. As winter comes in and the fish get larger, they may start migrating downriver over several months or they may stay in upper portions of the watershed for a while. "That’s the nice thing about that stock," Jateff said. "It has that variability that allows the fish to survive in variable conditions." Better than a third of this year’s run is made up of three-year-old hatchery fish, which Jateff said usually indicates good ocean survival. Destruction of Entiat salmon eggs "standard operating procedure" When Winthrop hatchery workers were ordered to destroy the eggs from more than a dozen stray Entiat River Chinook salmon that missed a left turn, they were following standard operating procedure, according to a state fish official. Joe Foster, regional fish program manager with the state Department of Fish and Wildlife in Ephrata, said the long-term plan for Chinook salmon in the upper Columbia involves an attempt to breed out lingering influences of non-native fish. The Entiat River and Wenatchee River Chinook salmon eggs have historically been and are currently mixed with eggs from the Carson hatchery on the lower Columbia River, Foster pointed out. "We do not want to incorporate them into the Methow program," Foster said. "They are not indigenous...What we’re trying to do is rebuild the runs with the native stock." Foster said a small number of strays is unavoidable, but the dozen or more Entiat River fish who found themselves plucked out of the fish ladder at Wells Dam were unacceptable. "Nature itself does allow strays; it’s not uncommon. In the natural situation it's not a bad thing, but when you get a large number of fish coming in that have the potential to completely change the genetic pool, then it becomes a matter of concern." Opinion | Sports |
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