The breeding, rearing, and transplantation of fish by artificial means is called pisciculture, in other words, fish farming. It is the principal form of aquaculture, while other methods may fall under mariculture. It involves raising fish commercially in tanks or enclosures, usually for food. 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. Fish species raised by fish farms include salmon, catfish, tilapia and cod.