High-tech tuna boats from countries such as France, Italy, and Spain use sonar and airplane spotters to find schools in the remaining tuna grounds, located off the coasts of Cyprus, Egypt, and Libya. (Read "High-Tech Fishing Is Emptying Deep Seas, Scientists Warn" [February 22, 2002].)
Most of the bluefin tuna currently caught is caged alive in floating tuna farms in Croatia and across the Mediterranean. Small juvenile fish are used as seed stock in the farms.
There they are fed and fattened for about three to six months before going to market.
Much of the highly prized fish stock is exported to sushi and sashimi markets in Japan (Japan photos, maps, and more). Tuna prices can reach as much as U.S. $15 a pound ($33 a kilogram) in Tokyo. A single large adult bluefin tuna can sell for upward of $50,000.
WWF says at least 25,000 tons (23,000 metric tons), and perhaps more than 30,000 tons (27,000 metric tons), of tuna from the Mediterranean and eastern Atlantic go to Japan.
WWF has asked the European Union, whose member nations do most of the fishing, to close bluefin tuna fisheries as an interim measure.
It has also asked ICCAT to implement a strict recovery plan before it convenes for its annual meeting in November.
"The recovery plan should include a strong reduction of fishing on the last remaining adult stock by implementing a three-month seasonal closure from May to July," Tudela said.
WWF is also calling for the real-time reporting of catches to ICCAT, the compulsory presence of ICCAT observers on vessels and at tuna farms, and the increase of the minimum catch size to 66 pounds (30 kilograms) from 22 pounds (10 kilograms).
According to Alain Bonzon, an official with the United Nations Food and Agriculture Organization, a new evaluation of eastern Atlantic and Mediterranean bluefin tuna stock is being carried out by ICCAT, and the results should be finalized before its November meeting.
East and West
Not all experts, however, paint as grim a picture as the WWF report.
Vjekoslav Ticina, a tuna expert at the Institute of Oceanography and Fisheries in Split, Croatia, agrees that "fishing bluefin tuna over maximum sustainable yield cannot be sustained over the long term and will eventually lead toward a decrease in wild bluefin tuna biomass.
"However, I think the WWF is exaggerating [in its depiction of the situation]," he said.
Ticina says there are two bluefin tuna stocks, one in the eastern Atlantic with a spawning site in the central part of the Mediterranean Sea and the other in the western Atlantic with a spawning site in the Gulf of Mexico.
"The state of the tuna stock in the Mediterranean and eastern Atlantic is much better than the state of [tuna] stock in the western Atlantic," Ticina said.
That is in part because tuna in the western stock start to spawn at age eight or higher, while tuna in the eastern stock begin to spawn at age four.
"[The eastern stock] can consequently sustain higher fishing pressure than western stock," Ticina said.
He also says there are signs that the Japanese market, the main driving force behind the tuna industry, is becoming saturated.
In addition, sea ranching, in which tuna is caught in the wild and then penned and fattened, makes it possible to satisfy greater market demand without further increase in fishing mortality, Ticina says.
"A clear distinction between [fisheries] conducted in accordance with management regulations and illegal tuna [fisheries] should be done," he said. "These activities shouldn't be put in the same basket."
Free Email News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).
SOURCES AND RELATED WEB SITES