I have problems with bullheads also, IMO it works best in this order.
1. Hook and line, worm and bobber, and time.
2. Trapping, sometimes it works sometimes not
3. Wait for them to school on top of the water and give them a dose or your favorite .12ga
You can search the past posts, this topic has been addressed many times, and there are some really good threads.
IIRC a Lmb can eat a bluegill 1/3 its length, so I would think its about the same for crappie.
