The Gulf of Mexico is the sole breeding ground of the Atlantic Bluefin Tuna.
How many year classes will we lose to dispersants still being sprayed Tom?
Description & Behavior
Atlantic bluefin tunas,
Thunnus thynnus (Linnaeus, 1758), aka blue fin tunas, blue-fin tunny, bluefin tunas, horse mackerels, northern bluefin tunas, and squid hounds..., are regarded as one of the most highly evolved fish species and one of the most prized fish in danger of
overfishing.
Tuna, originating from the Greek word meaning "to rush," usually swim at speeds of 1.5-
4 
knots, can maintain
8 
knots for some time, and can break
20 
knots for short periods. These are one of the most magnificent fishes in the sea. One fish can sell for hundreds of thousands of dollars. A
342 
kg tuna sold at Tokyo's Tsukiji fish market for 32.49 million yen ($396,700 US dollars), the highest price for a single fish since record-keeping began in 1999, that's 95,000 yen ($1,157) per kg!
Atlantic bluefin tunas are the largest member of the
Scombridae Family (albacores, bonitos, mackerels, tunas). They are one of the largest bony fishes and can reach lengths of up to
3 
m, although they are more commonly found from 0.5-
2 
m in length. Adult weights range from 136-
680 
kg, although the upper weight range is rare, especially now. They can dive as deep as
914 
m, and are known to swim long distances as they are a highly migratory species.
Atlantic bluefins are dark blue to black on their dorsal (upper) surface and silvery ventrally (underneath). Bluefins are known for their finlets that run down their dorsal (upper) and ventral (lower) sides toward their anal fin. There are 12-14 spines in their first dorsal fin and 13-15 rays in their second dorsal fin. Their anal fin has 11-15 rays. The average natural lifespan of bluefin tunas is 15-30 years.
Atlantic bluefins are homeothermic ("warm-blooded") and are therefore able to
thermoregulate 
keeping their body temperatures higher than the surrounding water, which is why they are so well adapted to colder waters.
World Range & Habitat
http://marinebio.org/species.asp?id=236