San Francisco Chronicle: The plight of California salmon has become almost an obsession among environmental groups and fishermen in California and Oregon, but nobody seems to know what is ailing the scaly critters. What is known is that the pink fish are disappearing from our waters so fast that all ocean fishing was banned this year in California and Oregon for the first time ever. Riley Smilth, of Fort Bragg, climbed into the mouth of a fiberglass salmon at Pier 39 in San Francisco in April. The …