More than a quarter million sockeye salmon returning from the ocean to spawn are either dead or dying in the Columbia River and its tributaries due to warming water temperatures, the AP reports; federal and state fisheries biologists say the warm water is lethal for the cold-water species and is wiping out at least half of this year's return of 500,000 fish. "We had a really big migration of sockeye," said Ritchie Graves of the National Oceanic and Atmospheric Administration. "The thing that really hurts is we're going to lose a majority of those fish." He said up to 80 percent of the population could ultimately perish. AP reporter Keith Ridler has a full report here.