General Information

COMMON NAMES: Bigeye Tuna; French Patudo, Thon aux Grands Yeux TRADITIONAL NAMES: ‘A‘ai (RR AK), ‘A‘ai < Toeveri (AT), ‘A‘ai Potopoto (MK), To‘everi (MT), Tuava (PL), Kakasi (TS TW), Punua (MH), Matawula (PK); Other Polynesian - Aahi Tatumu (TAH) GLOBAL DISTRIBUTION: NATIVE cirumtropics - subtropics COOK ISLANDS STATUS: Native; S.Group and N.Group. Uncommon. PLUS:; Marine, pelagic 0-800m SIGNIFICANCE LIST: Prized food fish, and third most important in the lingline fishery.; Poisonous to eat if stored poorly KEY FEATURES: To 240cm and 200kg, usually 15kg. Fusiform, round, elongate; with very small scales. Dark blue above, yellowish behind eye, whitish sides and belly. Dorsals similar in height; 1st Dorsal yellow; 2nd pale yellow, ±height of 1st; Anal pale yellow; finlets yellow with BLACK MARGIN. Pectorals and tail grey. Pectorals long in small fishes, reaching behind 2nd Dorsal base. SIMILAR SPECIES: See under Yellowfin Tuna (Thunnus albacares). Also note that Bigeye Tuna juveniles are often misidentified as Albacore (Thunnus alalunga).

Cook Islands Distribution

View Distribution Map

Southern Group: Present    Makatea:
RR	MG	AT	MK	MT	AK	PL	TK	MN
P						P

Northern Group:
TN	MH	RK	PK	NS	SW
+			P

Thunnus obesus (Lowe, 1839)
SYNONYMS: Germo obesus; Neothunnus obesus; Parathunnus obesus; Thunnus mebachi; Thynnus obesus [O]

TAXONOMY: ANIMALIA; CHORDATA; GNATHOSTOMATA (Jawed Vertebrates); PISCES; OSTEICHTHYES; Perciformes; Scombroidei; SCOMBRIDAE, Thunnini

SIGNIFICANCE NOTES -
POSITIVE SIGNIFICANCE: Prized food fish, and third most important in the lingline fishery.. Comments: Important in artisanal fishery and in oceanic commercial fishery.
NEGATIVE SIGNIFICANCE: Poisonous to eat if stored poorly

GENERAL NOTE: Relatively slow growing, reaching maturity at 3-4 years; and at eight years can reach 200cm and 180kg. The most commercially valuable tuna of teh longline fishery. Sold to the sashimi (fresh fish) markets of Japan. Widespread from 40degN to 40degS; with juveniles near the surface and older fish down to 500m. (Josh Mitchell, CINew 9/Aug/03)

Vouchers:
Rarotonga: specimens 1960s long-liner "the first 'big eye' tuna caught in the Cook Islands" (Percival 67, p.61-3 PIM, in Sims88). Tongareva: listed in T&P85. Pukapuka: informant reports at NBSAP meeting, 2/2004.

References:
Special Reference: Collette, B.B. & C.E. Nauen, 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 Fish. Synop. (125)Vol.2:88.

p.445 Randall et al. (1990) Fishes of the Great Barrier Reef....
p.602 Burgess et al. (1988) Atlas of Marine Aquarium Fishes (TFH)
plate 96-09 Allen (1997) Marine Fishes of Tropical Australia....
Species No. 343 Munro (1967) Fishes of New Guinea

Data Update History (information):
zTX, zB02, zM02, zD02

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