At this time and under your situation the bigger LMB were probably breeding females and many of the smaller fish were males. Take out LMB 12+- inches and under (unless one looks fat if so put it back) until you have taken out about 25 to 30 lbs per acre this year.

I would have left the breeding females as they are big enough to eat their small kin. They are good at that but need your help to thin things out.