To prevent overpopulation, it is important to maintain a balance between the number of crappie and other fish species in the pond. This can be done by stocking the pond with a variety of fish species, including predators that will help to keep the crappie population in check. Additionally, it is important to monitor the crappie population and take steps to reduce their numbers if necessary. This can be done by removing some of the crappie from the pond or by introducing sterile crappie.