Since 1960 the Bluefin Tuna population has declined by 97%. Their decline began when they became a valuable fish for the Japanese commercial fishery. Toro is the belly cut of Bluefin. Currently they are fished at four times the sustainable level, largely for the sushi trade.
Because they live in the high seas and migrate widely, beyond international borders, legislating their protection has not happened. The International Commission for the Conservation of Atlantic Tunas (ICCAT) has ignored scientific data and upheld unhealthy fishing levels because of powerful commercial fishing lobbies.
Recently (March 2010) European fisheries agreed to join in support for listing the Bluefin as endangered under CITES. The initiative failed because of protest from Japan, Canada, Austrailia and Greenland. search 'tuna' at southasia.oneworld.net/.../bluefin-tuna-
The Bluefin is really an amazing creature. It is one of the most evolved of fishes, and largest and fastest. It is warmblooded: they thermoregulate to keep warmer than surrounding ocean waters. Mature, they can grow to lengths of 14 feet.
Skipjack and Albacore Tuna are listed as best choices for eating by Seafood Watch (both are the tuna for canned tuna) if they are polecaught. The reality though is that most commercially exploited tuna is fished on longlines which are devastating to the tuna population as well as a number of other species in bycatch.
read more about bluefins at http://www.bigmarinefish.com
and to learn more about long line fishing see http://www.birdlife.org/action/science/s
Also please see my links page. There is a link to learn more about the tuna fishery and find out how you can get involved for ocean health.