Bluefin tuna being fished. Credit: The Image Bank / Getty Images

There’s a reason why scientists like to refer to the bluefin tuna as the “tigers of the sea.” The fish can grow to as much as 1,500 lbs. (700 kg), and can swim over 40 mph. Scientists who’ve tagged bluefin tuna in the wild to track their movements are amazed at how far the fish can range, swimming from their breeding grounds in the western Atlantic to the other side of the ocean in as little as a month. In a fairer world, these fish would be kings of the sea, apex predators sitting on top of the food chain.

But bluefin have one drawback, at least when it comes to their survival. They taste really, really, really good, especially when served as high-end sushi or sashimi. That fatty flavor has made bluefin tuna one of the most valuable species in the world, at least at the market—large bluefin tuna can go for tens of thousands of dollars, usually in the markets of Japan, where 80% of the demand for bluefin originates. As a result, bluefin are at risk of being fished out of existence.

That increasingly hard to ignore fact finally led the International Commission for the Conservation of Atlantic Tunas (Iccat) finally decided in 2008 to regulate bluefin fishing more closely, requiring paper documentation of catches and reducing the overall allowable take. The quota for 2009 was 27,180 metric tons of bluefin tuna, and in 2010 it was 13,525 metric tons. Although many environmentalists believed that even those quotas were too lenient, at least Icaat’s move represented a step in the right direction.

Just one hitch—no one’s following those quotas. That’s the conclusion of a new study put out by the Pew Environment Group that examined the amount of bluefin tuna actually being traded on the global market. The Pew study found that 141% more Atlantic bluefin tuna was being traded last year than was actually allowed to be caught, resulting in an overcatch of nearly 20,000 metric tons. The year before, the actual trade in bluefin exceeded the quota by 31%—put the two years together, and the total catch in 2009 and 2010 was double the quotes set by Icaat. And that data doesn’t account for the potentially vast black market in illegal, unreported bluefin fishing, which by some estimates could represent an additional 20% of trade figures.

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Why have efforts to tighten bluefin tuna fishing failed so far? The Pew report suggests that part of the problem can be found in Icaat’s paper-based catch records program. In principle, the policy should allow bluefin to be tracked from the boat to the ranch (many tuna are caught young and then fattened up in underwater pens) to the market. But evidently, that hasn’t worked in practice, as Pew’s Lee Crockett told the BBC:

As you can see, they clearly haven’t fixed the problem – in fact, the gap [between the reported and total catches] has increased, which is a pretty clear indication that they need to do a much better job of making sure that the catch reports track the quota.

One solution then might be to institute an electronic-based tracking system for bluefin tuna that would be tougher to fool. Each bluefin tuna could receive a physical bar code that would allow it to be tracked and cross-checked as it made its way through the global market, from sea to plate.

Video from TIME: The Trouble with Tuna

Of course, such a tracking system would be of little use unless international regulators are willing to actually willing to enforce those quotes—and so far, there’s little indication that they would. This is a perennial problem in ocean conservation issues—migrating fish like the bluefin tuna pass through open waters, which are still treated as a barely governed global common. There are really no collective institutions strong enough to enforce fishing limits in international waters, which leaves the tuna at the mercy of the market. And given how valuable bluefin tuna are, it’s not hard to see why fishermen would flout the rules—especially when those rules are barely enforced, as a powerful report by the International Consortium of Investigative Journalists concluded a year ago.

So that throws the ball back to consumers. As long as the demand for bluefin tuna remains as strong as it is now, it’s hard to see how any regulations could successfully curb the fishing industry—until there simply aren’t enough bluefin to go around. Do the tigers of the sea a favor—skip the toro.

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Bryan Walsh is a senior writer at TIME. Find him on Twitter at @bryanrwalsh. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME