MOVEMENTS OF BLUEFIN TUNA (THUNNUS THYNNUS L.) TAGGED IN THE MEDITERRANEAN SEA WITH POP-UP SATELLITE TAGS

• Main Authors: G. De Metrio, G. P. Arnold, J. M. De La Serna, B. A. Block, P. Megalofonou, M. Lutcavage, I. Oray, M. Deflorio
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Norwegian Sea; Iceland; North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.505.8904; http://www.iccat.int/Documents/CVSP/CV058_2005/no_4/CV058041337.pdf

Although there have been several studies of the migratory movements of Atlantic bluefin tuna (Thunnus thynnus, L.) between the Western and Eastern Atlantic, the two-stock hypothesis remains untested and exchange rates are still unidentified. TUNASAT, an EU-funded research programme involving Italy, Spain, Greece and the UK, which was carried out during the three-year period 1998-2000 in the Mediterranean Sea and the Strait of Gibraltar, and a subsequent tagging program funded by the Italian Ministry of Agriculture and Forestry Policies, which was carried out during 2003 in the Eastern Mediterranean, aimed to better understand this problem. Both bluefin tuna tagging programs were executed using pop-up satellite tags. Results from both tagging programs indicated that adults < 100 kg remain in Mediterranean after spawning and feed in areas of high primary productivity, as indicated by SeaWiFS satellite data for chlorophyll-a concentration. After spawning large bluefin 150-230 kg migrate into the eastern North Atlantic, either south towards the Cape Verde Islands or north to Iceland and the Norwegian Sea. Some large bluefin move to and fro between the Alboran Sea and Atlantic, feeding on both sides of the Strait of Gibraltar. No evidence of transatlantic movement was observed. RÉSUMÉ