Bullet tuna

1. Dorsal naked area does not extend forward to pectoral-fin tips
2. Bars in dorsal naked area only slightly oblique
3. Posterior end of corselet spanning 1–5 scales wide under second dorsal-fin originDorsal fins widely separated
4. Dorsal fins widely separated
5. 8 dorsal finlets, 7 anal finlets
6. Large median keel with 2 smaller keels on either side of caudal peduncle
7. Interpelvic process single, large
8. 43–48 gill rakers on first gill arch
9. Tongue with 2 longitudinal ridges

Bluish black to purple above, silver below. Scaleless corselet area containing ~15 vertical dark bars behind first dorsal fin.

Up to 50 cm TL (smaller than Auxis thazard) and up to 1.84 kg in weight.1

Circumglobal in warm waters.

Inshore pelagic, found from the surface to 200 m depth.

Mostly eats small fishes, particularly clupeids, and also squid, crustaceans and zooplankton such as crab and stomatopod larvae. Highly migratory forming same and multi-species schools. Maturity varies by region, length at 50% maturity for both sexes is estimated to be 24 cm FL in India and 18.8 cm FL in the Philippines.2, 3 Age of first maturity in Japan is 1.25 years.4 Auxis rochei is a multiple spawner producing between 31,000–162,800 eggs per spawning depending on the size of the fish. Eggs are pelagic and considered an important part of the food web due to their high abundance. Maximum age is estimated at 5 years.5

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