Based on many reports from anglers and responses to a poster program, biologists for the Division of Wildlife and Freshwater Fisheries identified several wild bighead carp captured by anglers from 1998 through 2000. These fish were much larger than specimens reported from other river basins in the country, with several fish in excess of 60 pounds. Although anglers sometimes catch them, bighead and silver carp are primarily filter feeders, eating a variety of small plants and animals called plankton. The environmental impacts of these fish are unknown but they could adversely impact many native species of fish due to competition for food. Sport fish such as bass and crappie eat plankton early in their lifecycle.
Shad also rely heavily on plankton for food.
Large numbers of Asian carp could reduce the amount of forage available for these important sport fish. Although not documented, if Asian carp are reproducing in Alabama, larval and juvenile Asian carp could displace native fishes competing for the already limited backwater nursery habitat so critical to many species. Large numbers of Asian carp in our rivers could also adversely impact native mussel populations. Alabama has the largest diversity of mussels of any State, but many of these species are already threatened or endangered due primarily to habitat loss. The presence of a large planktivore like these Asian carp could dramatically impact threatened mussels by reducing the amount of food available.