Mike -
FYI - there fair numbers of wild winter steelhead that also spawn in the lower Skagit tribs -Alder, Hansen, Day etc.

Something to consider - If indeed as you think a CnR is reducing the success fo the spawners why in the heck are you fishing at that time of the year? Even if the females in a CnR area are 95% as successful at spwaning as unfished females that is a substantial lost in the population viability - the same effect on the population as a 10% havest rate.

Tight lines
S malma