Welcome to PB. How many lbs of fish do you think you have kept by year and type ( example - 09 , 10 lbs LMB , 15 lbs BG , 3 lbs crappie) ? A drawdown in winter 4 yrs ago may have little effect on the current populations. May be that the LMB and crappie have caught up with the BG and are now overcrowded. What do the crappie look like (size and condition)? You have lots of options with several ponds.