Tuna
For the Polynesian god, see Tuna (Polynesian mythology).
Thunnus alalunga
Thunnus albacares
Thunnus atlanticus
Thunnus maccoyii
Thunnus obesus
Thunnus orientalis
Thunnus thynnus
Thunnus tonggol
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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 Slender tuna
Allothunnus fallai
- Bullet tuna Auxis rochei rochei
- Frigate tuna Auxis thazard thazard
- Kawakawa (little tuna or mackerel tuna) Euthynnus affinis
- Little tunny (little tuna) Euthynnus alletteratus
- Butterfly kingfish (Butterfly tuna) Gasterochisma melampus
- Dogtooth tuna