Take a look at this.
http://www.wa.gov/wdfw/hat/escape/e000914.pdf

Seems like the count for Spring/Summer Chinook on the wallace(closed) was alot higher then what came back to the Samish river(opened). Some of the numbers and openings don't make sense. SO I guess you can say I don't really have the answer as to why they aren't opening up Silvers on the sky. There are probably tons of them in there, but not worth getting caught targeting them. Oh yeah, lots of them humpies too. YUCK...lol