Forget about soggy sandwiches or the flavourless stuff out of cans: the best tuna has always been a prized dish, which Aristotle wrote about with enthusiasm around 2,400 years ago. The fate of the giant bluefin tuna is another example of the way our oceans are being plundered to satisfy gourmet tastes. This year's harvest of the Atlantic tuna that spawn in the Mediterranean was a disaster for the fishermen of the islands off Sicily. Their traditional shoreline mattanza (slaughter) has been fruitless, a result of the massive increase in legal and illegal fishing in the region.
Scholars believe that Homer referred to the Sicilian mattanza in the Odyssey, when he compared the pile of Penelope's slaughtered suitors to the fish lured by fishermen onto the beach and "heaped on the sand". Now those that are still caught are located at sea by more advanced technology, in operations sometimes financed by the mafia. Researchers at the University of British Columbia have said that sonar and satellite devices are now being used to identify the areas where the tuna gather. While legitimate international exports of fish have doubled in the last two decades, that of tuna has nearly trebled. The trade in bluefins is especially lucrative and a single large specimen can sell in Japan - where it is highly prized - for up to £80,000. Though some tuna is farmed, the Worldwide Fund for Nature has warned that many are wild fish that have been penned while they fatten.
Pablo Neruda wrote an ode to "the one and only pure ocean machine, unflawed, navigating the waters of death", but a species of the tuna that inspired him could soon disappear. The common skipjack tuna found in supermarket tins is in no immediate danger, but the bluefin is now threatened in the Pacific as well as the Mediterranean and Atlantic. The rage for sushi in Los Angeles and London, as well as Tokyo, is eating away at another of nature's wonders.