Return of the sockeye

In 1992, a single male sockeye salmon managed to swim 900 miles from the mouth of the Columbia River to Redfish Lake located deep in Idaho’s Sawtooth Mountains — the end of his migratory journey. Biologists dubbed the sole survivor, “Lonesome Larry.”

By 2010, the Northwest Power and Conservation Council happily reported record-setting runs for sockeye —387,000 had climbed the fish ladders at Bonne...