Positive they are crappie. I will do electrofishing next spring. I just wonder if I'm helping out the crappie population by catching bass. I wonder if I should leave them to eat the smaller crappie.
You've got a lot going on in the pond, so not all courses of action will support each goal you have. If you want bigger LMB, then you still want to cull smaller LMB. However, leaving smaller LMB in the pond may help eliminate some young crappie, thus maybe helping reduce the crappie population. In this example alone, one action ignores one goal while supporting another.
Crappie also tend to become too big to be eaten by LMB due to body shape. So, smaller LMB could put a dent in newly born crappie; however, crappie are know to have inconsistent spawns from year to year. One year may recruit a lot of crappie while the next year, recruitment is low. It seems like you're seeing this in your pond. So, leaving smaller LMB in the pond to address a situation that may not happen each year may not give the results you hope to see.
Crappie also compete with LMB for forage, so that's an overall consideration.
For me, I like having diversity in my pond, so this might be an approach to take:
1) Cull all crappie caught, unless you catch an unusually large specimen.
2) Cull all LMB under 12 or 14"; if you catch a LMB under 14" that is unusually fat, maybe leave that one in the pond.
3) Consider a feeding program if you don't already have one in place; this will increase the size of the existing LMB in the pond, and those 'larger' LMB may have a stronger impact on the crappie population.
4) Consider adding a limited amount of larger predator fish (Northern Pike, Tiger Muskie, or maybe Blue Catfish).
5) Determine if you've got White or Black Crappie. There may be some difference in management approach depending on which you have.
