End of the line for the world's big fish?
Everybody in the business knows that the Atlantic population of bluefin tuna is in worse trouble than the Pacific population, but how much worse? Well, here's one measure: Stanford University's Tag-a-Giant programme is now paying US$1,000 per tag to fishermen in the Atlantic and Mediterranean who return the tags after they catch the tuna, whereas fishermen in the Pacific get only US$500 for a tag. Trust the market to tell you the truth.
Another measure of the bluefin's scarcity value is the fact that two months ago, the owners of two sushi restaurants in Japan and one in Hong Kong banded together to pay US$175,000 for a 233kg bluefin tuna at Tokyo's Tsukiji fish market. The primary market for bluefin tuna is sushi, and the demand is so great that the fish are disappearing fast in both oceans.
That's why the first order of business at the Convention on International Trade in Endangered Species (Cites) conference that begins in Doha, Qatar, on Saturday, is a complete ban on the international trade in bluefin tuna. Cites is the only port of call, because no other international body can intervene to defend a fish species.
So, are the bluefin near the edge? Probably 'yes'. When they tagged 600 of them in the North Pacific, they got 300 tags back: half the tuna that Tag-a-Giant caught were caught again by the commercial fishery. In the eastern Atlantic and Mediterranean, scientific data suggests that the species has dwindled by 60 per cent in the past six years.
It would help a lot if the European Union were solidly behind a ban, for Cites needs a two-thirds majority of the 175 member states to put a species on the endangered list or take it off again. Most Atlantic bluefin tuna are caught in the Mediterranean, where they migrate to breed, but even within the EU there is not unanimous support for a ban.
As for Japan, which consumes around 80 per cent of the world's bluefin tuna catch, it does not just oppose the ban. Its chief delegate to the Cites conference, Masanori Miyahara, says that it will 'take a reservation' to any ban: that is, ignore it. Even if the eastern Atlantic tuna population is given some form of protection at the Doha meeting, it is unlikely to do more than slow its decline.
According to a 2006 report in the scientific journal Nature, 90 per cent of the really big fish - tuna, marlin, swordfish and the like - are already gone. The middle-sized fish are following, and the solution does not lie in last-minute bans on fishing for the next species to reach the brink of extinction. These fish are all part of a food chain, and the whole system needs a chance to recover.
We need short-term pain for long-term gain. We are going to lose the principal source of protein for one-fifth of the human race in the next few decades unless drastic measures are taken. Fish breed fast. Let them breed back up to their historic levels, and we could then sustainably take a catch that is three or four times greater than the current, unsustainable level. Or we can go on squabbling about the last few fish until they are all gone.
Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries