The salmon looked like shadows gliding silently beneath the surface of a pool between the foaming rapids of rugged Butte Creek. Suddenly, with a splash, a big glittering fish leaped out of the water, then another and another. The spring-run chinook were jumping this past week in the remote, forested gorge outside Chico. "This is the last best run of wild salmon in California," said Allen Harthorn, 56, the executive director of Friends of Butte Creek, who has been fighting for more than a decade to save the historic - and once sacred - spring run of chinook in this...