The channel catfish, Ictalurus punctatus, has a cylindrical body with skin lacking in scales; spots on the sides. Soft fin rays with exception of dorsal and pectoral fins which have spines. Adipose fin present. Barbels located below and at the corners of the mouth, with two barbels on the dorsal surface of the head anterior of the eyes and posterior of the snout. Deeply forked caudal fin and curved anal fin with 24-29 rays.
Interest in channel catfish aquaculture began when the United States Fish and Fisheries Commission began stocking fish collected from the wild in the 1870s. Channel catfish were native primarily to the Mississippi River Valley but were widely introduced throughout the nation by the Commission. Spawning was first achieved in 1890 in aquaria, at which time it was learned that the male guards the eggs during incubation. Pond spawning was first observed in 1914 at a government hatchery. Spawning nests (nail kegs) were first used in 1916 and the numbers of fingerlings produced per stocked female increased. Indoor hatching of channel catfish eggs in troughs equipped with paddle-wheels to move the water in a manner that simulates the fanning of the eggs by the male fish was first accomplished in 1929.
Commercial aquaculture was first considered to be economically practical in the late 1950s. Catfish farming developed rapidly during the 1960s and 1970s as improvements in pond management, disease identification and control, and prepared feeds were developed and adopted by farmers. The commercial industry developed in the southern United States within the original range of the species. At least 90 percent of the farmed fish are produced in the Mississippi River Valley region.
Channel catfish have been introduced into Europe, Russian Federation, Cuba and portions of Latin America. The primary interest in many countries appears to be recreational fishing.
Channel catfish are native to flowing waters in temperate environments within North America, including southern Canada and northern Mexico. Adults first spawn at two or three years of age. Spawning in nature occurs in the spring, beginning in about March in the southern part of the range and later as latitude increases. Once egg laying and fertilization are complete, the male will chase the female from the nesting area and tend to the eggs by fanning the mass with his fins to keep oxygenated water moving over them.
Channel catfish are reared in ponds, cages, and circular tanks or linear raceways in both the United States and China. Monoculture dominates in the U.S., while both monoculture and polyculture with traditional species such as carp occurs in China. Formulated feeds are employed in both nations. The details presented below refer to channel catfish culture in the United States of America.
The majority of channel catfish are grown in ponds. Alternatively, adults may be paired in pens within a spawning pond. In both instances nests comprised of metal cans, drain tiles, wooden boxes or other types of enclosures of appropriate size are utilized.
Some farmers specialize in selling fry or fingerlings to producers of market-sized fish, while others purchase fingerlings for grow-out; however, many farmers operate their own hatcheries and grow-out operations.
Water quality management is critical to problems with pond catfish production. High stocking densities, particularly during summer, can lead to stress, disease, and mortality due to deterioration in water quality, particularly low dissolved oxygen. During critical periods ponds are monitored and emergency aeration is provided when necessary to maintain dissolved oxygen levels within an acceptable range.
Channel catfish are sometimes reared in flow-through tanks or raceways, indoors or outdoors. Recirculating system culture has been attempted over the years but few, if any, economically successful farms have been developed.