A bluefin tuna, tagged by researchers in August 2008, was caught a year later by a professional bait boat off the coast of northern Spain. The animal had internally implanted electronic tag which enabled its migratory movements and the depth of these, amongst other data, to be obtained. First estimations of the geographical location of the recovered tag revealed that this fish had undertaken migrations between the Azores and Portugal during the winter, later to return to the Gulf of Bizkaia in spring and also that it had dropped, during the winter, to depths of more than 1000 meters.