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Tuna
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Tuna

For the Polynesian god, see Tuna (Polynesian mythology).

Tuna
Scientific classification
Kingdom:Animalia
Phylum:Chordata
Class:Actinopterygii
Order:Perciformes
Family:Scombridae
Genus:Thunnus
Species
    Thunnus alalunga
    Thunnus albacares
    Thunnus atlanticus
    Thunnus maccoyii
    Thunnus obesus
    Thunnus orientalis
    Thunnus thynnus
    Thunnus tonggol

Tuna are several species of ocean-dwelling fish in the family Scombridae, mostly in the genus Thunnus. Tuna are fast swimmers and like most other fish species are cold-blooded. Unlike most ocean fish species, which have white flesh, the flesh of tuna is pink. This is because the tuna's blood has a higher oxygen carrying ability than other fish species. Some of the larger tuna species such as the bluefin tuna can raise their blood temperature above the water temperature with muscular activity. Though not really warm-blooded, this enables them to live in cooler waters and survive a wider range of circumstances.

Tuna is a popular seafood. Some varieties of tuna, such as the bluefin, are endangered because of overfishing, while others are part of well maintained fisheries, such as the bigeye or yellowfin.

Mercury levels are oftentimes relatively high in tuna, as they sit higher in the food chain.

It is difficult to keep tuna in a captive environment; Monterey Bay Aquarium is one of the few aquariums in the world that successfully keep tuna in display.

Types include:

Tuna are a common target for big-game fishing, and are mostly caught on artificial lures.

Other species

Species of several other genera (all in Scombridae) are commonly named "tuna":

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