North Lewis River spring chinook bounce back

By Al Thomas, Columbian Outdoors Reporter

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ARIEL — There’s good news — finally — for the long-suffering spring chinook run in the North Fork of the Lewis River.

The Washington Department of Fish and Wildlife anticipates a return of 1,400 adult spring chinook, more than double the dismal forecast of 700.

The agency already has close to 1,000 spring chinook at its hatcheries on the Lewis.

“It’s a start,’’ said Aaron Roberts, manager of several Southwest Washington hatcheries for the Department of Fish and Wildlife.

The state’s ideal number is 1,300 adult spring chinook for hatchery spawning purposes, but is satisfied with 1,000, Roberts said.

“I’m thrilled if we can get at least 500 females,’’ he said.

As of late last week, there were 526 females in the hatcheries.

“Spring chinook in the Lewis typically show up at the end of May,’’ said Chris Karchesky, fish passage coordinator for PacifiCorp, the utility that operates the three hydroelectric dams on the North Fork of the Lewis. “Now, we’re normally at about 20 percent to 30 percent of the run.’’

Roberts said some of the female spring chinook are small and may have fewer eggs than typical.

Once the hatcheries have about 1,100 adult spring chinook, the Department of Fish and Wildlife will give PacifiCorp the green light to start transporting a few chinook upstream of Swift Dam for release in the upper North Fork of the Lewis at Eagle Cliff.

The transport of spring chinook, coho and winter steelhead into the upper watershed is part of the federal relicensing of Merwin, Yale and Swift dams.

The fish spawn in the upper North Lewis and their offspring are collected at Swift Dam and truck downstream to Woodland for release.

Adult spring chinook have not been available to transport upstream since 2012, Karchesky said.

The Department of Fish and Wildlife shifted to releasing hatchery spring chinook in the fall, rather than spring, beginning with the 2013 brood year.

The North Fork of the Lewis has its warmest water temperatures in fall, due to heat captured in the reservoirs. The warm water makes the young fish start the biological process of adapting to saltwater. Holding the young until the typical spring release time added stress on the fish and is believed to be the principle cause of the decline.

“The chinook have been coming in in droves,’’ said Karchesky. “It’s nice to see.’’

Woodland release pond — Construction will begin work soon on a salmon and steelhead release pond adjacent to the North Fork of the Lewis River in Woodland.

Todd Olson, director of compliance for PacifiCorp, said the facility will cost more than $1 million. It will include four raceways on a five-acre parcel.

Young fish gathered at the Swift collector facility at Swift Dam will be taken by truck and placed in the Woodland ponds overnight before release into the lower North Fork of the Lewis.

Olson said the utility intends to have the ponds complete by the end of 2017.

Frank Shrier, principal scientist for PacifiCorp, said the ponds are a licensing requirement to help measure the mortality of young fish from being hauled in a truck.