I would also add that, originally, Chinook were big river fish. Spawned in big mainstems. That was, I believe, "why" they were big. In our relentless effort to kill as many as quickly as possible what we have created is a piscivorous chum. At 20 pounds an adult can spawn in much smaller water.

Maybe that is how we will "save" Chinook. make them 10-20 pound creek fish. Since we want to use the big rivers for things other than salmon, maybe that is the route to go.