Blackfin tuna

Blackfin tuna (Thunnus atlanticus )

The blackfin tuna (Thunnus atlanticus ) is a relatively small of tuna and an important food fish. It has a maximum length of 1.08 meters and a maximum weight of 20 kg. With the same size skipjack tuna (Katsuwonus pelamis ), it forms mixed flocks and hunt fish, cephalopods and crustaceans.

Features

The average length of the blackfin tuna is 72 cm with a weight 6-7 kg. His spindle-shaped body reaches its greatest height in the middle of the first dorsal fin. The blackfin tuna is oberseits metallic dark blue, silvery gray on the sides, colored milky white on the belly. The first dorsal fin is dark, the second dorsal fin and the anal fin dark with a silvery sheen, the Flössel dark with a yellowish tinge. The pectoral fins are of medium length, reaching 22 to 31 % of the total length of the fish. The blackfin tuna has 39 vertebrae, of which 20 caudal vertebrae ( vertebrae behind the anus). A swim bladder is present. The number of gill Reuse rays is low, 19 to 25 are located on the first branchial arch.

Fins formula: dorsal fin XIII/14-15, anal fin 0/13-14.

Dissemination

The blackfin tuna is a Warmwasserart and lives in the tropical and subtropical western Atlantic, north to Massachusetts and south to Rio de Janeiro and Trindade and Martim Vaz. The northern boundary is the 20 ° isotherm.

Reproduction

In Florida, the black fin tuna increased from April to November with a peak in May, in the Gulf of Mexico from June to September.

Use

The blackfin tuna regarded as a good food fish and is caught with nets and fishing.