SUMMARY

• Main Authors: V. Ortiz De Zárate, D. Macías, K. Satoh, H. Saito
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: North Atlantic
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.598.601; http://www.iccat.int/Documents/CVSP/CV056_2004/no_4/CV056041450.pdf

North Atlantic to study the spawning activity of bluefin tuna (leg 1 and 2) and the habitat and stock structure of marlins and swordfish in the tropical Atlantic (leg 3 and 4). As secondary research objectives, all tuna species caught were retained and sampled to study their biology. A total of 38 adult albacore (Thunnus alalunga), ranging from 91.6 cm. to 119 cm. fork length, were caught during the complete cruise from June 15th to October 16th. From the histological analysis it is concluded that all male albacore caught during the 3rd leg of the cruise were mature. From a total of 5 female albacore caught, one female caught in the Central North Atlantic during the first leg showed a mature stage of gonadal development, meanwhile the 4 females caught in the North tropical Atlantic area in the 3rd leg presented different stages of maturity, one female with evidence of imminent spawning and two others with signs of recent spawning activity in the north east tropical Atlantic area. RÉSUMÉ Le bateau de recherche japonais Shoyo-Maru a réalisé en 2002 une campagne de recherche dans l’Atlantique centre-nord afin d’étudier l’activité reproductrice du thon rouge (phases 1 et 2) et l’habitat et la structure du stock de makaires et d’espadon dans l’Atlantique tropical