Description: A large, stocky tuna. Body fusiform, elongate, and slightly compressed, with maximum girth near the middle of the first dorsal fin. Narrowly separated dorsal fins, and moderately long pectoral fins. Acute conical snout. First dorsal fin is high anteriorly, with a concave margin, and second dorsal and anal fins are sickle shaped. The caudal peduncle has a long midlateral keel between two short oblique keels. Metallic dark blue dorsally and white ventrally; live specimens have an iridescent blue stripe on the side.
Global Distribution: Worldwide in tropical and subtropical waters; absent from the Mediterranean. View Map
BIOLOGICAL FEATURES
Size: Maximum length 250 cm (total length); common length 180 cm (fork length); maximum published weight 210.0 kg.
Reproduction: Eggs and larvae are pelagic. Spawning may take place year-round in tropical waters.
Maturity: range 100 - 125 cm
Behavioural ecology: Juveniles and small adults school at the surface in mono-species groups or mixed with other tunas such as Thunnus albacares and Katsuwonus pelamis; may be associated with floating objects. Adults stay in deeper waters.
Population structure & migrations: Highly migratory species.
ECOLOGICAL FEATURES
Depth range: FishBase: 0 - 250 m, usually 0 - 50 m.
Habitat: Pelagic, oceanic species. Occurs in areas where water temperatures range from 13°-29°C, but the optimum is between 17° and 22°C.
Feeding habits: Feeds on a wide variety of fishes, cephalopods and crustaceans.
Trophic level: FishBase: 4.5
FISHERIES
Commercial interest: Important commercial species in Madeira.
Conservation status: Vulnerable.
Nutritional information & food safety:
REFERENCES
Collette B.B., Nauen C.E. (1983). FAO Species Catalogue Vol. 2. Scombrids of the world. An annotated and illustrated catalogue of tunas, mackerels, bonitos and related species known to date. FAO Fisheries Synopses, 125 vol.2, 137 pp.
IUCN (2014). The IUCN Red List of Threatened Species. Version 2014.1. www.iucnredlist.org
McEachran J.D., Fechhelm J.D. (2006). Fishes of the Gulf of Mexico. Vol. 2. Scorpaeniformes to Tetraodontiformes. University of Texas Press, Texas, USA, 1008 pp.
