FURTHER RESULTS OF TAGGING MEDITERRANEAN BLUEFIN TUNA WITH POP-UP SATELLITE-DETECTED TAGS

Abstract

SUMMARY Six (50%) of the 1998 tags and six (15%) of the 1999 tags popped up successfully; no return from the tags placed in 2000 has been obtained to date. Several of the tags have shown interesting results. In fact, a tag deployed at Barbate was detected in the Greenland Sea at 75.123°N 1.095°E, the most northerly reported position for bluefin tuna; another tag deployed in Barbate popped up at 20.269°N 29.673°W, closed to the southern limit of the eastern Atlantic stock; the results of three of the tags deployed in the area of Bocche di Bonifacio suggested that this may be a feeding area: two of them popped up in the same area after 180 and 240 days respectively, while a third tag was recovered from a fish recaptured in the same area after 65 days at liberty. Furthermore, the possible causes of the low rate of tag return are discussed.