It's all the fault of the Japanese, of course

The New York Times has an editorial about tuna:

The numbers of endangered bluefin tuna are rapidly dwindling, due to vast overfishing fueled by Japan’s insatiable sushi appetite. The international body set up to conserve these fish has utterly failed to do its job. But a small and clever innovation may slow their decline: special hooks designed to help commercial fishing boats in the Gulf of Mexico avoid catching bluefin accidentally.
The hooks are simply thinner than usual, and bend under the weight of a bluefin, whose average size when caught in the Gulf is 485 pounds. The hooks still work for yellowfin tuna and swordfish, which weigh a lot less. Fishing for bluefin in the gulf has been illegal since the 1980s, but longline boats often catch them without meaning to. Whether landed or released, the bluefin die.
The National Oceanic and Atmospheric Administration will require the fifty longline vessels in the Gulf to start using the hooks on 5 May. Some fishermen are already using them, because they work so well. The sooner the better, because the Gulf is where the bluefin spawn each spring.
Even if the new hook ends bluefin bycatch completely, it will only slow the species’ extinction spiral. The only real hope for survival is for the world to ban international trade in bluefin, as it has for the tiger and blue whale. The United States supports such a move, and the United Nations Convention on International Trade in Endangered Species could have done so last year, but its members buckled under ferocious lobbying from Japan. The International Commission for the Conservation of Atlantic Tunas, responsible for regulating the bluefin catch, has for years ignored the advice of its own scientists and set quotas unsustainably high. Stocks of Atlantic and Mediterranean bluefin dropped by more than sixty percent just in the last decade. Time is running out.