Study Questions Call to Breachby Rocky Barker
Idaho Statesman, January 20, 2007
Critics say number of fish used for research is too small to draw conclusion
Salmon carrying high-tech acoustic tags from Idaho made the trip to the northern tip of Vancouver Island in Canada at about the same rate as salmon from the Yakima River in Washington, in a new study released this week by a Canadian scientist.
David Welch's preliminary results suggest that the Idaho fish that have to swim through eight dams survive the first part of the ocean trip as well as salmon that only must negotiate four dams. That's important because the Yakima salmon return as adults at a rate of 5.2 times better than the Idaho fish.
"While we caution that our first-year results should be viewed as tentative, they strongly suggest that the ocean plays the critical role in the management and conservation of these Columbia River salmon stocks, and that ignoring these issues leads to more blame being ascribed to the hydrosystem than is appropriate," Welch wrote in his report.
Fisheries biologists on both sides of the breaching debate said Welch's sampling size of salmon is too small to make the conclusions he makes.
But the Coalition for Idaho Water, a group of businesses that oppose breaching the dams, said in a press release that Welch's study "puts a bullet in the heart of arguments that tearing out the dams will somehow become a silver bullet remedy" to save salmon.
"This new science refutes claims by environmentalists that the four lower Snake dams need to be removed," said Norm Semanko, president of the Idaho Water Coalition.
Bert Bowler, a retired fisheries biologist with Idaho Rivers United, which supports dam breaching, said it has never been viewed as a silver bullet. "But this particular study is not going to change the best available scientific view that removing the Snake River dams is the best way, if not the only way, to recover Snake River salmon stocks," Bowler said.
John Williams, a research fisheries biologist with the National Marine Fisheries Service in Seattle, whose research has suggested the Columbia's hydro dams have had less impact than Bowler and other scientists say, said the small number of fish released with acoustic tags, and the small number of fish detected in the ocean, are not enough from which to draw a conclusion.
"Saying there is no effect of dams is difficult to say when you have as few of fish as he had," Williams said.
Welch agrees. But he believes that as he gets results in 2007 and beyond he will be able to show eventually whether the current view of fisheries biologists is correct or whether his view - that the difference in returns of Snake and Yakima fish is caused by something in the ocean - prevails.
"I think we have very clear results that are very surprising," Welch said. We need to see if we get the same results in 2007."
Welch's team released a total of about 1,000 salmon from hatcheries in Kooskia on the Clearwater River, and on the Yakima River in Washington. The fish had acoustic tags planted inside them so special receivers, placed in the ocean along the shelf running north from the Columbia River, could detect them.
The acoustic monitoring system Welch has developed called Pacific Ocean Shelf Tracking System, is the latest effort to determine where salmon go after they leave rivers up and down the coast.
"No one in the world has done the stuff we've done," Welch said.
Bowler is skeptical Welch can make his case without tagging thousands more fish and setting up receivers both south of the Columbia and out toward the open ocean. Welch said his system will expand and be open to the use of other researchers as well.
"Like it or not, we're going to continue to see significant shifts in the ocean," Welch said. "Like it or not this is going to be the baseline of research."
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