SUMMARY

• Main Authors: G. De Metrio, G. P. Arnold, B. A. Block, J. M. De La Serna, M. Deflorio, M. Cataldo, P. Megalofonou, S. Beemer, C. Farwell, A. Seitz
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Greenland; Greenland Sea; Iceland; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.468.5211; http://www.iccat.int/Documents/CVSP/CV054_2002/no_2/CV054020415.pdf

A total of 84 bluefin tuna were tagged using 61 PTT-100 single point and 23 PAT archival satellite tags- PAT tag experiments were conducted in collaboration with the Tuna Research and Conservation Center, USA – in the Mediterranean and the Eastern Atlantic between June 1998 and August 2000. Considering both types of tag, the overall return rate obtained in the two areas during the whole period was 31.3%. The return rates from PTT-100 and PAT tags were 20.3 % and 61.9%, respectively. No transatlantic migrations were observed. Several of the tags have shown interesting results: two PTT-100 tags deployed off the Strait of Gibraltar was detected in the Greenland Sea and in an area close to the southern limit of the eastern Atlantic bluefin tuna stock; a PAT tag deployed in the Mediterranean was detected in the Iceland Sea; most of the tags deployed in the area of Bocche di Bonifacio (Corsica) popped up in the same area. Inspection of SeaWiFS satellite data (for chlorophyll-a concentration extraction) showed that higher concentrations of chlorophyll-a appeared in the areas where most of the tags were detected. These areas of high productivity may therefore be feeding areas for both pre- and post-spawning fish. Tag trials were made at different sites in order to test the ability of the Argos satellite system to detect tags in the western Mediterranean and the eastern North Atlantic.