FM,
The crappie take over a pond in a short time if you don't have a lot of predators to eat them. I am spending my winter attempting to cull some "stunted" crappie out of a 5.1 acre pond. This project is akin to kicking yourself in the butt. If you have crappie they will abide, and feeding them is not a needful thing.
Actually, you are catching and keeping every crappie and bluegill you catch in order to make room for the walleye and small mouth I added in the fall.
I disagree that the crappie are stunted. The older larger ones are smart enough not to sit under six round lights eating minnows dropping from the lights. All this while their buds are sucked back up through those lights never to be seen again.
Ice fishing is a poor method for sampling a fishery, especially fishing in the same area of the pond over and over again.