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U.S. Makes Scientific Case
by Jonathan Brinckman
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In a Science article, federal biologists back the government's position
that breaching isn't the way to save salmon
Breaching dams might not be an effective way to save the Columbia River Basin's largest, most-prized salmon from extinction, the federal government's top salmon researchers say in today's edition of the journal Science.
The article by Peter Kareiva, Michelle McClure and Michelle Marvier of the National Marine Fisheries Service lays out the scientific case for the federal government's recommendation this summer that four federal dams on the lower Snake River be left in place.
The evidence the three biologists present is "pretty stark," said Brian Gorman, a spokesman for the fisheries service, the federal agency in charge of salmon recovery. "It certainly suggests that breaching is not a panacea."
Its publication in Science adds credibility to the agency's position, Gorman said Thursday. "Some say we are fudging numbers or doing fuzzy math. This article will dispel those myths."
In July, the fisheries service recommended that the four dams, operated by the U.S. Army Corps of Engineers, be left alone while other steps are taken to help salmon. Those actions would focus on restoring the rivers and streams where salmon spawn and restoring the Columbia River estuary, where young salmon feed and grow before striking out to sea.
The fisheries service is to make a final recommendation Dec. 15, five weeks after Tuesday's election. But agency staff said the timing may depend on who wins the presidential race.
George W. Bush, the Republican nominee, has said that he opposes breaching dams. Vice President Al Gore, the Democratic nominee, has not taken a position, but he has said that he would support doing what is needed to prevent extinction of the threatened Snake River salmon stocks.
Opponents of breaching said the Science article bolsters their argument no matter who wins the election.
"We are on a course change in the region," said Bruce Lovelin, executive director of the Columbia River Alliance, an industry group. "Two or three years ago, dam breaching seemed to be the solution. Now, based on this report, it seems the problem is more in the estuary and the ocean."
Conservationists and scientists who work for Northwest tribes and the Oregon and Idaho fish and wildlife departments have said that the four dams must be breached to save Snake River salmon from extinction.
On Thursday, they said the biologists' arguments in Science do not change their opinion.
"This paper is not insignificant, but it is certainly not the end of the game," said Jeff Curtis, western conservation director of Trout Unlimited. "All of this stuff will have to stand up in court."
Curtis and others say they expect to sue the agency about its recommendation, and the authors of the study will have to defend their findings.
The fisheries service biologists' research contrasts with a five-year, $5 million study by federal, state and tribal biologists that concluded in 1998 that breaching the four dams would be the most certain way of saving Snake River salmon. The fisheries service abandoned that study and commissioned Kareiva's research effort.
Kareiva and his colleagues developed a mathematical model to analyze how improved survival at each stage of the salmon's life cycle -- just after hatching in streams, swimming past the dams, lingering in the estuary and growing to adulthood in the open ocean -- would translate into greater overall health of salmon populations.
They found that greater survival in the early life stages and in the estuary has the most dramatic effect on population growth. Under some of their study's assumptions, the improvements in survival from removing dams would be too little to save Snake River spring/summer chinook.
"Remarkably, even if every juvenile fish that migrated downstream survived to the mouth of the Columbia," the salmon would continue to decline, the researchers wrote.
Proponents of breaching said the authors' conclusion that it may not be effective is simply wrong.
Inadequately considered, they said, is the fact that going through the dams' spillways or surviving in the barges used to carry millions of young fish past the dams weakens salmon and makes them more likely to die later, either in the estuary or in the ocean.
"There's a lot of evidence for delayed mortality, but they don't consider it," said Charlie Petrosky, a biologist for the Idaho Fish and Game Department.
McClure, one of the authors, said the agency doesn't know how large the delayed mortality rate is. The study says breaching the dams could reverse the decline of salmon if the rate was 9 percent or greater.
Supporters of Bush were quick to say that the new report vindicated his opposition to dam breaching. But Gore's backers said they still think the vice president has been right to say that he would be guided by the best science.
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