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Study on Salmon Survival is Moving in the Right Direction by Terry Flores Idaho Statesman, December 10, 2008

A new study on the survival of migrating salmon on dammed and undammed rivers in the Pacific Northwest is important to the recovery of salmon populations because it correctly asks the critical question: What factors are causing survival problems for fish?

In new research findings, David Welch of Kintama Research in British Columbia, with other scientists, reports that young salmon and steelhead in the dammed Columbia and Snake rivers are surviving equally as well as those in the undammed Fraser River.

While this study is an important step to better understanding the factors affecting fish survival, several more years of data are necessary before any conclusions can be drawn with respect to the impacts of dams.

However, common sense suggests that factors other than dams are affecting fish survival, given this year's experience. Sockeye runs crashed in the undammed Fraser River, while sockeye and other salmon stocks are abundant in the dammed Columbia and Snake rivers. And, in the same year, the West Coast ocean fishery south of Cape Falcon completely collapsed.

The encouraging news is that this continuing research involves future studies aimed at identifying where and why Pacific salmon are dying at sea. "My personal judgment is that the real survival problems are out in the ocean, after the fish leave the rivers," Welch said in a news report. Possible negative factors include ocean warming, increased salmon predation by seals and sea lions, and parasite infestations of wild smolts spread by coastal salmon farms.

Other researchers agree. Ray Hilborn, professor of fishery sciences at the University of Washington, said, "I believe that everyone now accepts that all the chinook salmon in the Pacific Northwest (apart from Alaska) have been very negatively influenced by ocean conditions."

This study does suggest that the billions of dollars spent on dam modifications and restoring salmon habitat on the Columbia and Snake rivers are bearing fruit. We hope so. Families and businesses in the Northwest have made huge contributions to these improvements through their electric bills since the 1970s. And, the most recent plan for operating the Columbia and Snake hydroelectric system to minimize impacts on listed fish, calls for billions more in expenditures. Continuing studies like this are critical to knowing how to best focus our fish recovery efforts so that fish benefit and the region's electricity consumers get the most value from their investment.