Salmon Hopes Pinned On Wild, Hatchery Mix Researchers Look To 2001 Run As Next Measure Of Program

Idaho fisheries researchers are hoping their work mingling hatchery-raised chinook salmon with wild fish may lead to a regionwide program that helps recover the endangered species.

It sounds routine. States have used hatcheries to boost salmon runs for decades, since dams on the Columbia and Snake rivers sent naturally reproducing fish into a tailspin. What’s changing this decade is the mixing of select hatchery fish with wild fish to see if their offspring give the runs a better chance.

“The objective is to use the hatchery as a tool for rebuilding wild stocks,” said Peter Hassemer, research biologist with the Idaho Department of Fish and Game. He reported some preliminary findings Tuesday at a meeting of the Northwest Power Planning Council, a four-state group overseeing salmon recovery projects.

Wild fish generally are considered hardier than hatchery fish because they grew up fending for themselves, and because they come from a wider gene pool.

State biologists captured some wild salmon before they could spawn in 1993 and bred them in captivity, where more of the young salmon initially survive than in the wild. Then it released the young salmon to head downriver to the Pacific Ocean. This year, those salmon returned as adults, and some were turned away from the hatchery and forced to breed with wild salmon.

So far, so good. The hatchery fish are breeding with wild salmon, and are doing so in target areas rather than wandering up and down streams to breed, Hassemer said.

But the most important results won’t be known until 2001, when a second generation of salmon returns.

Then, the state will assess whether the program has increased the long-term productivity of wild salmon, and whether those fish show any signs of in-breeding.

Ken Casavant, the chairman of the Northwest Power Planning Council’s fish and wildlife committee, said he hopes Idaho’s research shows that careful mixing of hatchery fish with wild fish can boost natural reproduction throughout the Columbia River basin.

He shook off criticism from environmental and fishing organizations, some of whom contend it’s best to keep the wild fish genetically pure so they can recover naturally if the dams and other problems are fixed.