17 Cages and in-pond raceways

Abstract

Cages and in-pond raceways are culture systems that can be used where open-pond culture is not feasible or advantageous. The ability to utilize almost any body of water is the most unique advantage of cages and in-pond raceways. The abundance of watershed ponds throughout the United States offers opportunities to exploit underutilized or multiple-use aquatic habitats to culture catfish where temperature regimes and water quality parameters are acceptable. In some states, certain public waters such as rivers and reservoirs are designated for fish culture, and cages and in-pond raceways can be employed to culture catfish in such waters where permitted. All problems with cage culture center on high-density confinement offish. The high density and close proximity of fish can create localized water quality problems, particularly low dissolved oxygen concentration, and facilitates the rapid transfer of diseases among fish within the cage. The high density of fish at the pond surface attracts predators. Cages can attract poachers and vandals because access to the fish is easy. Finally, the lack of any consumption of natural food organisms means that feed must be nutritionally complete. The scale of commercial cage and raceway production of catfish is very small compared to open-pond culture in the United States. Catfish cage and in-pond raceway culture operations are scattered throughout the South, Midwest, and West. Most of these are small-scale and produce fish for personal use and/or local niche markets.