San Francisco Chronicle: Most of California’s native salmon, steelhead and trout species face extinction by the end of the century unless the state acts quickly to provide adequate freshwater and habitat, according to a study released Wednesday by the state’s leading salmon expert. Twenty of 31 species of the prized fishes are in sharp decline, including the Sacramento River winter run of chinook salmon, the Sierra’s California golden trout and coastal coho, according to the study by Peter Moyle, a nationally …