Fisheries Farming

Fish farming or pisciculture involves raising fish commercially in tanks or enclosures, usually for food. It is the principal form of aquaculture, while other methods may fall under mariculture. A facility that releases juvenile fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery. Worldwide, the most important fish species used in fish farming are carp, tilapia, salmon, and catfish.

Fish culture in natural waters is concerned with the replenishment and improvement of the fish stocks of rivers, lakes, reservoirs, and seas. The increasing impact of man on such waters (water pollution and construction) has impeded or disrupted the natural replenishment of fish stocks. Thus, the rearing of fish, that is, fish-farming, is needed to maintain the existing fish life and to improve an ichthyofauna of minor value. Semimigratory (pike-perch, carp, roach) and migratory fishes (sturgeon, beluga, stellate sturgeon, inconnu.

Atlantic salmon, chum salmon, pink salmon, Baltic vimba, and kutum) are particularly threatened. Semimigratory fishes inhabit lakes, rivers, and the mouths of rivers; and migratory fishes inhabit seas but travel, often hundreds of kilometers, up rivers for reproduction. However, as a result of construction on the rivers, the spawning grounds are cut off by dams from the feeding areas, and timber floating on the rivers leads to the destruction of the spawning grounds.

Fish-farming makes it possible to replace partially or completely natural breeding and to populate the natural waters with acclimatized species of fish. Fish hatcheries engaged in incubating roe and rearing fry for subsequent release into natural waters have been constructed on rivers and in the basins of many seas. To replenish the stocks of such semimigratory fish as pike-perch, bream, and carp, the network of spawning and rearing farms is being expanded. Important work is being done by acclimatization stations, which supply stock to various bodies of water as many as 300 times a year.

Portfolio of Fisheries Farming