Any of several species of North American freshwater catfish in the genus Ictalurus, valued as food and sport fishes. Bullheads are related to the channel catfish (I. punctatus) and other large North American species, but their tail is squared, rather than forked, and they are generally less than 12 in. (30 cm) long. The black bullhead (I. melas) is found in the Mississippi Valley, the yellow and brown bullheads (I. natalis and I. nebulosus) east of the Rocky Mtns., and the flat bullhead (I. platycephalus) in coastal streams between North Carolina and Florida. The name is sometimes applied to sculpins.