Wenatchee, Washington, July 30, 2008—Tourists watch sockeye salmon swim past viewing windows at the Rocky Reach Dam on the Columbia River.

Sockeye are returning up the river and its tributaries this summer in numbers not seen since 1955. No one is sure why; some say improved ocean conditions, others credit extra water spilled over hydroelectric dams in 2006 and 2007 to ease fish passage downstream.

Whatever the reason, expect "gone fishing" signs to proliferate over the next few weeks.

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