Good advice. In conjunction with the PSD/RSD method (which uses creel (catch) surveys) include good visual analysis and seine surveys (keep records - size and weight and #s - RW ) and an occasional shock survey ( CPUE = catch per unit of effort in ES surveys) and you will have a very good system for assessing this problem.

This combo of methods compensates for the potential for error associated with each of these tools as noted in the above quote and as mentioned by Dave.

One word of caution with using just the RW (skinny looking fish) method. Time of year makes a big difference. A 110 % RW female in Feb. may be an 85% RW female 3 mths later. Same for males who just spent a mth nesting and guarding yoy.