Actinopterygii (ray-finned fishes) > Perciformes
(Perch-likes) > Scombridae
(Mackerels, tunas, bonitos) > Scombrinae
Etymology: Thunnus: Greek, thynnos = tunna (Ref. 45335).
Environment / Climate / Range
Marine; brackish; pelagic-oceanic; oceanodromous (Ref. 51243); depth range 1 - 250 m (Ref. 6390), usually 1 - 100 m (Ref. 55289). Tropical; 15°C - 31°C (Ref. 168), preferred 28°C (Ref. 107945); 59°N - 48°S, 180°W - 180°E
Length at first maturity / Size / Weight / Age
Maturity: Lm 103.3, range 78 - 158 cm
Max length : 239 cm FL male/unsexed; (Ref. 40637); common length : 150 cm FL male/unsexed; (Ref. 168); max. published weight: 200.0 kg (Ref. 26550); max. reported age: 9 years (Ref. 72462)
(total): 11 - 14;
soft rays: 11 - 16;
Vertebrae: 39. Fish with very long second dorsal fin and anal fin, which in some may reach well over 20% of the FL. The pectoral fin is moderately long, usually reaching beyond the second dorsal fin origin but not beyond the end of its base. Color is black metallic dark blue changing through yellow to silver on the belly. The belly frequently has about 20 broken, nearly vertical lines. The dorsal and anal fins and finlets are bright yellow.
Worldwide in tropical and subtropical seas, but absent from the Mediterranean Sea. Highly migratory species, Annex I of the 1982 Convention on the Law of the Sea (Ref. 26139).
An oceanic species occurring above and below the thermoclines. Pelagic in open water , but rarely seen near reefs (Ref. 48637). They school primarily by size, either in monospecific or multi-species groups. Larger fish frequently school with porpoises, also associated with floating debris and other objects. Feed on fishes, crustaceans and squids. It is sensitive to low concentrations of oxygen and therefore is not usually caught below 250 m in the tropics (Ref. 28952, 30329). Peak spawning occurs during the summer, in batches (Ref. 9684, 51846). Eggs and larvae are pelagic (Ref. 6769). Encircling nets are employed to catch schools near the surface (Ref. 9340). Marketed mainly frozen and canned (Ref. 9684), but also fresh (Ref. 9340) and smoked (Ref. 9987). Highly valued for sashimi (Ref. 26938).
Spawn throughout the tropical and equatorial waters of the major oceans (Ref. 6390). At higher latitudes, spawning is seasonal, with peaks in summer; may continue throughout the year at lower latitudes (Ref. 6390).
Yellowfin tuna are multiple spawners, ie they spawn every few days over the spawning period (Ref. 6390). Eggs and sperm are released into the water for fertilisation (Ref. 6390).
Collette, B.B. and C.E. Nauen, 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. Rome: FAO. FAO Fish. Synop. 125(2):137 p. (Ref. 168)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Fisheries: highly commercial; aquaculture: experimental; gamefish: yes
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5039 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01445 (0.01152 - 0.01813), b=3.02 (2.98 - 3.06), based on LWR estimates for this species (Ref. 93245
Trophic Level (Ref. 69278
): 4.4 ±0.4 se; Based on diet studies.
Resilience (Ref. 69278
): Medium, minimum population doubling time 1.4 - 4.4 years (K=0.13-0.42; tm=2-5; tmax=8; Fec=200,000).
Prior r = 0.6, 2 SD range = 0.27 - 1.34, log(r) = -0.51, SD log(r) = 0.4, Based on: 2 M, 33 K, 4 tgen, 4 tmax, 6 Fec records
Vulnerability (Ref. 59153
): Moderate to high vulnerability (51 of 100) .