Species Spotlight: Bluefin Tuna

Bluefin Tuna, © Norbert Wu/Minden Pictures

© Norbert Wu/Minden Pictures
Although the supermarket’s canned food aisle may be the closest many Americans have come to a school of tuna, the species is among the oceans’ most fascinating fish.

The biggest and baddest of the bunch, the Atlantic bluefin tuna, can weigh as much as 1,400 pounds—bulking-up on a gourmet diet of crab, lobster and squid as well as small fry, such as sardines, herring and mackerel.

Found in the Atlantic Ocean and the Mediterranean Sea, the bluefin prowls some of the planet’s most frigid waters. The Atlantic population spawns in the Gulf of Mexico from April to May, and conservationists are concerned that the BP oil spill may have harmed these fish.

Able to survive up to 20 years in the wild, bluefin tuna have only a few natural predators, including killer whales, sharks and a handful of other big fish. But over the past 50 years, a staggering 74 percent of eastern Atlantic and Mediterranean bluefins has disappeared. Scientists say that overfishing is to blame.

Often served raw, a small slab of bluefin fetches up to $20 in Japanese sushi restaurants, while a whole 440-pound fish reeled in a record $220,000 market bid in 2009.

International efforts to ban the commercial trade of Atlantic bluefin floundered earlier this year. So unless the critically endangered delicacy comes off the menu soon, its bluest days are still ahead.  

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