Bluefin tuna live mainly in the pelagic ecosystem of the North Atlantic and its adjacent seas, especially in the Mediterranean Sea.
Geographically, it is widely distributed throughout the North Atlantic Ocean, from Ecuador to Norway and from the Black Sea to Mexico.
Unlike other tuna species, this is the only one that lives permanently in the temperate waters of the Atlantic. This claim means that bluefin tuna preferentially occupy the surface and subsurface waters of the coastal and open-ocean areas, but archival marking and ultrasonic telemetry show that bluefin tuna often reach depths of 500 m to 1,000 m.
Like other species of tunas and sharks, Atlantic bluefin tuna is a pelagic predator that must swim continuously to ventilate and generate enough heat to maintain vital organs (eg, muscles, eyes, brain) and raise body temperature above the water’s temperature. The complex structure of your circulatory system allows you to minimize heat loss and maintain internal body temperature above that of seawater. Thanks to its endothermic capacity, it can withstand cold (3 ° C) and warm temperatures (up to
30 ° C). The bluefin tuna has a particularly well developed circulatory system10, which makes it a warm-blooded fish and a fast swimmer (72.5 km / hour), with an enormous capacity for migration.