Actually, back in '75 I believe there was no minimum size for Chinook in the sound. It was raised sequentially since then to deal with catch imbalances and probably to deal with sorting; who wants to keep a 12" Chinook?

Last data I saw on Chinook survival in SSound was that the yearling Chinook survived as "well" as the fingerlings. Like Oncy says, putting more yearlings out in deep SS is throwing good money after bad.

There is something seriously wrong with how fish are surviving there. I have not heard of too much effort being made to find out.