Chapter 10: History and Status of Introduced Populations Outside the United States
In this chapter, we review the introduction and spread of black carp Mylopharyngodon piceus outside their native range. We address the reasons for introduction and discuss data gaps in the state of our knowledge. In an attempt to understand trends and patterns of introduction and establishment, we present the information on different geographic scales, including world region and country, and, subsequently, by major basin and drainage.
Black carp have been introduced for a variety of reasons, often intentionally, but many times not. As will be seen, the reasons and motives for introduction are in no way mutually exclusive. Reasons or explanations behind introductions include (1) for culture or polyculture, with intent to produce fish as a food for human consumption (e.g., Vietnam, Taiwan, Japan, South Africa); (2) to create a new commercial fishery (involving the stocking of fish into the wild); (3) for use as a biological control agent to reduce mollusk populations (e.g., snails in reservoirs; clams; Israel, former Soviet Union); (4) for use as a biological control agent to combat fish and human parasites through direct predation on host snails (i.e., mostly in aquaculture ponds; e.g., China, former Soviet Union, United States); (5) for research or experimental purposes, largely involving investigation into its potential as biological control agent, or as a culture animal; and (6) accidental or unintentional introductions, typically as a result of young fish inadvertently being included with shipments of other fish, usually young grass carp Ctenopharyngodon idella. In many cases, the purpose for introduction into any one place is a combination of two or more of the above reasons (details on black carp use as biological control agents are provided in another chapter). It has been suggested that black carp could be used in ponds where snails compete for food with herbivorous fishes (Bardach et al. 1972), but we are unaware of introductions occurring for this purpose. As a whole, introductions have involved essentially all life stages of black carp, including adults, juveniles, larvae, and, presumably, eggs. Some introductions involve open-water releases, while others relate to fish in captive or controlled conditions.