Conservationists have warned the amount of Atlantic bluefin tuna traded on the global market last year was more than double the quota set for the endangered fish.
The Pew Environment Group said after a decade of heavy overfishing of the species in the Mediterranean, lower quotas were imposed in 2008 in an attempt to conserve the fish.
But analysis revealed that while the quota in 2010 was within the recommendations made by scientists for the first time, the amount traded on the market was 141% higher than the limits set.
The figure does not include black market sales of Atlantic bluefin tuna, which would push up the total catch of the fish even higher.
The total quota set by the International Commission for the Conservation of Atlantic Tuna (ICCAT) between 1998 and 2010 was 378,698 tonnes, while the official catch reported by the body was 395,554 in that time.
But Pew estimates that the amount traded, excluding on the black market, was more than 490,000 tonnes, which is an extra catch of almost 100,000 tonnes that had a market value of €2bn.
