Tuna
A tuna is a saltwater finfish that belongs to the tribe Thunnini, a sub-grouping of the mackerel family (Scombridae) – which together with the tunas, also includes the bonitos, mackerels, and Spanish mackerels. Thunnini comprises fifteen species across five genera,[1] the sizes of which vary greatly, ranging from the bullet tuna (max. length: 50 cm (1.6 ft), weight: 1.8 kg (4 lb)) up to the Atlantic bluefin tuna (max. length: 4.6 m (15 ft), weight: 684 kg (1,508 lb)). The bluefin averages 2 m (6.6 ft), and is believed to live for up to 50 years.
Tuna and mackerel sharks are the only species of fish that can maintain a body temperature higher than that of the surrounding water. An active and agile predator, the tuna has a sleek, streamlined body, and is among the fastest-swimming pelagic fish – the yellowfin tuna, for example, is capable of speeds of up to 75 km/h (47 mph).[2] Found in warm seas, it is extensively fished commercially, and is popular as a game fish. As a result of over-fishing, stocks of some tuna species such as the southern bluefin tuna have been reduced dangerously close to the point of extinction.[3]
| This article is one of a series on |
| Commercial fish |
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| Large pelagic |
| billfish, bonito mackerel, salmon shark, tuna |
| Forage |
| anchovy, herring menhaden, sardine shad, sprat |
| Demersal |
| cod, eel, flatfish pollock, ray |
| Mixed |
| carp, tilapia |
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