Green Earth Almanac: The Bluefin Boycott

The bluefin tuna, one of the world's most remarkable ocean creatures, is in trouble and needs your help. Overfishing is driving this mighty warm-blooded fish toward the brink of extinction, and yet many sushi restaurants continue to serve it.

Too often viewed only as sushi, the bluefin tuna is an extraordinary specimen of ocean wildlife, growing up to 10 feet long and sometimes weighing more than 1,000 pounds. Unlike almost all fish, bluefin tuna are warm-blooded and able to regulate their body temperature, which helps during their epic 60-day journeys across the Atlantic. Bluefin tuna are top ocean predators and sometimes hunt cooperatively, much like wolves. With streamlined bodies and retractable fins, bluefin can bolt through the water at speeds of up to 50 miles per hour and are capable of crossing oceans in the course of only a few weeks.

Unfortunately, due to its popularity as sushi, its high commercial value and its habit of crossing international boundaries, the bluefin tuna is being severely over-fished and is at risk of extinction. Since 1970, western Atlantic bluefin tuna have declined by more than 80% due to overfishing. Halfway through a 20-year government "rebuilding program" for the severely depleted population, there are barely any more fish than at the beginning of the program. In the eastern Atlantic, the majority of the decline has occurred in the past 10 years as they've been caught, without regulatory oversight, for fish farming.

The International Union for Conservation of Nature (IUCN) lists two species of bluefin, the Atlantic and the southern, as endangered or critically endangered on its "Red List" of imperiled species. The Pacific bluefin tuna is not yet listed, but overfishing is now occurring, according to the National Marine Fisheries Service.

In spring 2010, bluefin tuna took a major hit at the height of its spawning season: Scientists estimate that BP's massive oil spill in the Gulf of Mexico killed more than 20% of juvenile western Atlantic bluefin tuna that year. That estimate doesn't consider the expected long-term negative effects of the oil spill in the tuna's breeding habitat.

Sadly, bluefin tuna remains a prized menu item in some restaurants. The sushi market keeps prices for tuna high - a single tuna sold for nearly $396,000 in early 2011 - and encourages illegal and unreported fishing. Despite outcry from concerned people, many sushi restaurants across the globe continue to serve bluefin tuna. One common question: How can you tell if the tuna you are ordering is bluefin? The best way to tell is to check the menu and ask. Another broad rule of thumb: If its expensive, it could be bluefin.