Sorry to hear about the draining - however, what a neat way to analyze a fishery!
Lots of the regular guys here will undoubtly have some great advice to come, and probably some questions as well.
Pictures are always GREAT - I'd post them if you can.
If it were me, and my pond - I'd want to know the ages of some of those fish that you scooped up - especially the larger bass, and maybe even some that seem small. 29 adult LMB seems light to me for 1.5 acres and could be part of the problem - but I'd wonder as well - where are the bass YoY?
FH
