It is widely distributed in tropical and subtropical regions of all oceans and everywhere adheres to rather large depths (up to 200 m or more). Only young individuals of this species live near the surface, forming fairly dense flocks. Adult fish probably lead a solitary lifestyle. Bigeye tuna breeding occurs in the tropical zone and continues throughout the year. Its fertility varies from 2.9 to 6.3 million eggs, spawned in several portions; embryonic development at 28-29°C ends, as in other tunas, very quickly - after 21 hours.
Bigeye tuna feed on a wide variety of animals. Particularly important in the diet of this species are deep-sea and semi-deep-water fish - live-mouths, alepisaurs, godwit, hempyloids, as well as squids, pelagic octopuses, and large shrimps. Bigeye tuna reaches a length of 45-50 cm by the end of the first year of life, 70 cm at two years and 155 cm at the age of six, and sexual maturity occurs at a length of 90-100 cm. The largest known specimen of this species was caught off the coast of Peru : its length was 236 cm and weight 197 kg.
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