WWF Back on the Bluefin Trail

Through this three-year project – among the most ambitious bluefin tuna tagging work seen so far in the Mediterranean – WWF scientists are mapping tuna migrations around the basin, seeking answers to key mysteries on the migratory behaviour of this most valuable but also most imperilled fish.

WWF is tagging tuna this week with fishermen from Spain’s traditional tuna trap, the almadraba. This method for fishing bluefin tuna has existed around the Mediterranean for over 3,000 years and is intrinsically sustainable given the low vulnerability of tuna stocks to the trap. The fishery supports the livelihoods of hundreds of families but is in jeopardy – the fishermen have seen a drop in catches of over 80 per cent during the past two decades, given the exponential growth in industrial tuna fishing.

“While there are still tunas to tag, WWF hopes to shed light on the migrations of this incredible species,” said Dr Pablo Cermeño, WWF Mediterranean’s Tuna Officer. “Relatively little is known about the behaviour of Mediterranean tuna, yet it is repeatedly subject to rampant overfishing.”

On the Med tuna trail is a race against time to gather data before the overstretched fishery collapses. WWF recently released a new analysis showing that the reproducing population is collapsing now and could effectively disappear by 2012 if there is no change to current mismanagement and overfishing.

WWF’s tagging project is collecting information such as position and depth of the high-speed fish by fitting adult tunas (over 35kg) with ‘pop-up’ tags that are released from the fish at a specified time and float to the surface for the data to be read by satellite. Lifecycle information will also come from juvenile tuna tagged with ‘archival’ tags and recovered at point of catch.

“The plan behind this project to fill the significant gaps in knowledge of bluefin tuna’s migratory behaviour in the Mediterranean is starting to bear fruits,” said Dr Sergi Tudela, Head of Fisheries at WWF Mediterranean. “The first data gathered through WWF’s tagging project, soon to be released, will reveal surprising results.”

WWF is calling for a recovery period moratorium on bluefin tuna fishing in the current absence of effective rules for a sustainable fishery, lack of enforcement, and the high degree of illegal fishing.

The global conservation organization is also supporting calls to suspend international trade of Atlantic bluefin tuna by getting it listed on Appendix I of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) when contracting parties meet in early 2010.

WWF’s tuna tagging activities – planned in partnership with key international scientific institutions and fishing stakeholders in the Mediterranean, and made possible thanks to financial help from the Prince Albert II of Monaco Foundation – runs to the end of 2010.