FishA fish (: fish or fishes) is an aquatic, craniate, gill-bearing animal that lacks limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period.
Fish farmingFish farming or pisciculture involves commercial breeding of fish, most often for food, in fish tanks or artificial enclosures such as fish ponds. It is a particular type of aquaculture, which is the controlled cultivation and harvesting of aquatic animals such as fish, crustaceans, molluscs and so on, in natural or pseudo-natural environments. 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 as foodMany species of fish are caught by humans and consumed as food in virtually all regions around the world. Fish has been an important dietary source of protein and other nutrients throughout human history. The English language does not have a special culinary name for food prepared from fish like with other animals (as with pig vs. pork), or as in other languages (such as Spanish pez vs. pescado). In culinary and fishery contexts, fish may include so-called shellfish such as molluscs, crustaceans, and echinoderms; more expansively, seafood covers both fish and other marine life used as food.
Eurasian carpThe Eurasian carp or European carp (Cyprinus carpio), widely known as the common carp, is a widespread freshwater fish of eutrophic waters in lakes and large rivers in Europe and Asia. The native wild populations are considered vulnerable to extinction by the International Union for Conservation of Nature (IUCN), but the species has also been domesticated and introduced (see aquaculture) into environments worldwide, and is often considered a destructive invasive species, being included in the list of the world's 100 worst invasive species.
Asian carpSeveral species of heavy-bodied cyprinid fishes are collectively known in the United States as Asian carp. Cyprinids from the Indian subcontinent—for example, catla (Catla catla) and mrigal (Cirrhinus cirrhosus)—are not included in this classification and are known collectively as "Indian carp". Asian carp are considered invasive species in the United States. In June, 2022, the EPA funded initiative to rebrand Asian Carp as Copi was announced.
AquacultureAquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. lotus). Aquaculture involves cultivating freshwater, brackish water and saltwater populations under controlled or semi-natural conditions, and can be contrasted with commercial fishing, which is the harvesting of wild fish.
Silver carpThe silver carp (Hypophthalmichthys molitrix) is a species of freshwater cyprinid fish, a variety of Asian carp native to China and eastern Siberia, from the Amur River drainage in the north to the Xi Jiang River drainage in the south. Although a threatened species in its natural habitat, it has long been cultivated in China. By weight, more silver carp are produced worldwide in aquaculture than any other species of fish except for the grass carp. Silver carp are usually farmed in polyculture with other Asian carp, or sometimes with catla or other fish species.
Grass carpThe grass carp (Ctenopharyngodon idella) is a species of large herbivorous freshwater fish in the family Cyprinidae, native to the Pacific Far East, with a native range stretching from northern Vietnam to the Amur River on the Sino-Russian border. This Asian carp is the only species of the genus Ctenopharyngodon. Grass carp are resident fish of large turbid rivers and associated floodplain lakes/wetlands with a wide range of temperature tolerance, and spawn at temperatures of .
AnglingAngling (from Old English angol, meaning "hook") is a fishing technique that uses a fish hook attached to a fishing line to tether individual fish in the mouth. The fishing line is usually manipulated via a fishing rod, although rodless techniques such as handlining also exist. Modern angling rods are usually fitted with a fishing reel that functions as a cranking device for storing, retrieving and releasing out the line, although Tenkara fishing and traditional cane pole fishing are two rod-angling methods that do not use any reel.
Bighead carpThe bighead carp (Hypophthalmichthys nobilis) is a species of cyprinid freshwater fish native to East Asia, and is one of several Asian carps introduced into North America. It is one of the most intensively exploited fishes in fish farming, with an annual worldwide production of over three million tonnes in 2013, principally from China. Unlike the omnivorous common carp, bighead carp are primarily filter-feeding algae eaters, preferentially consuming zooplankton but also phytoplankton and detritus.
TroutTrout (: trout) is a generic common name for numerous species of carnivorous freshwater ray-finned fishes belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of which are members of the subfamily Salmoninae in the family Salmonidae. The word trout is also used for some similar-shaped but non-salmonid fish, such as the spotted seatrout/speckled trout (Cynoscion nebulosus, which is actually a croaker). Trout are closely related to salmon and have similar migratory life cycles.
Swim bladderThe swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their current water depth without having to expend energy in swimming. Also, the dorsal position of the swim bladder means the center of mass is below the center of volume, allowing it to act as a stabilizing agent. Additionally, the swim bladder functions as a resonating chamber, to produce or receive sound.
