Atlantic Bluefin Tuna
(Thunnus thynnus)

Size:
Length - Maximum of approx. 8 – 15 feet
Weight - Maximum of approx. 1000 – 2000 lbs.

Range:
The Atlantic bluefin tuna is found throughout the Atlantic Ocean, Mediterranean Sea, and the Gulf of Mexico. This giant fish spawns in both the Mediterranean Sea and the Gulf of Mexico.

Habitat:
Atlantic bluefin tuna travel vast distances throughout the year, often covering more than a 1000 miles in a matter of days. Frequently foraging in upwelling areas with high productivity, these oceanic giants spend a great deal of time in the open ocean, and are known to dive to depths of over 1 kilometer.

Diet:
These pelagic carnivores often prey on herring, mackerel, sardines, and squid.

Life History:
As mentioned above, Atlantic bluefin tuna spawn in the Mediterranean as well as the Gulf of Mexico. It has recently been discovered that while individuals spawning in these two distant locales will cross paths with one another throughout the rest of the year, but will always return to the Mediterranean Sea or the Gulf of Mexico respectively. While bluefin tuna do not reach maturity until 8 or more years, individual females are capable of producing over 10 million eggs per year.

Importance to Fisheries and Aquaculture:
Atlantic bluefin tuna may be the most highly valued species of fish in the oceans today. They are harvested by commercial fishermen with long line gear and seine nets. With the market price of this species continuing to rise, additional efforts are being made in producing this species under aquaculture. Although the fattening of captured young bluefin tuna in cages has been employed in areas like Canada and the Mediterranean since the 1970’s, these operations have only reduced the market uncertainty of a traditional capture fishery. However, new technologies are being developed in Japan, Europe, and the United States to raise bluefin tuna from egg to market, in order to offset the great deal of fishing pressure still put on wild stocks by the tuna fattening industry. With some success in these technologies, it may become possible to release young, hatchery-raised bluefin tuna into the wild to enhance wild stocks.

Fun Fact:
The bluefin tuna has one of the most advanced and efficient blood circulatory systems among all fish species, which allows for rapid distribution of oxygen throughout the body. As such, it maintains its superior strength over great periods of time. A good example of this stamina is their ability to wear out sport fishermen for over 7 hours, continuously taking out line and diving deep.

The largest Atlantic bluefin tuna recorded was caught in Nova Scotia in 1979. This fish weighed in at 1496 lb. 0 oz.