Atlantic Bluefin tuna (Thunnus thynnus)
Introduction: The Atlantic bluefin tuna (Thunnus thynnus) is a pelagic and schooling fish that is also known as the northern bluefin tuna, giant bluefin tuna. The species is the largest member of the Scombridae family and one of the largest bony fishes. Bluefin tunas are known to swim long distances and usually at high speed of up to about 1.5 knots and can also dive as deep as about 900 meters. The average lifespan of bluefin tunas is 15-30 years with up to 50 years for very large specimens.
Description: Atlantic bluefins are dark blue to black blue above and silvery underneath with a gold coruscation covering the body and bright yellow caudal finlets. Bluefins are known for their finlets that run down
…show more content…
The average weight at first maturity is about 25 kg. They spawn in two confirmed and widely separated areas. The first spawning ground exists in the Mediterranean Sea in the Eastern Atlantic (in the area of the Balearic Islands) while the second spawning ground is the Gulf of Mexico in the Western Atlantic. Although bluefin that were spawned in each area may forage widely across the Atlantic, they return to the same area to spawn. Usually, they spawn in large groups where they become highly vulnerable to commercial fishing. The estimated relative batch fecundity is more than 90 eggs/g of female’s body weight.
Bluefin tuna Aquaculture: The farming of Atlantic bluefin tuna began as early as the 1970s by Canadian fishermen who captured young fish and raised them in pens. The development of tuna farming continued in order to meet the growing demand for tuna in Japanese market. Cages are used for tuna fattening with the target to grow tuna to reach hundreds of kilos, which fetch premium prices in Japan. The farming of tuna depends on collecting tuna juvenile and young from the wild and moves them to grow-out and fattening cages. Several Mediterranean countries are actively engaged in tuna