Complex migration routes of Atlantic bluefin tuna (Thunnus thynnus) question current population structure paradigm

• Published in: Canadian journal of fisheries and aquatic sciences 2010-06, Vol.67 (6), p.966-976
• Main Authors: Galuardi, Benjamin, Royer, François, Golet, Walt, Logan, John, Neilson, John, Lutcavage, Molly
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal populations; Animal, plant and microbial ecology; Applied ecology; Behavior; Biological and medical sciences; Bluefin tuna; Environmental aspects; Exploitation and management of natural biological resources (hunting, fishing and exploited populations survey, etc.); Fish migration; Fisheries management; Fishery management; Fishes; Fundamental and applied biological sciences. Psychology; Marine; Metapopulations; Methods; Migration; Population structure; Sea water ecosystems; Site fidelity; Spawning; Synecology; Tagging; Thunnus thynnus; Tuna
• ISSN: 0706-652X; 1205-7533
• DOI: 10.1139/F10-033

Movements of Atlantic bluefin tuna ( Thunnus thynnus , ABFT) from specific western Atlantic forage grounds are not well described, and the extent of their spawning areas is mainly surmised. In 2005 and 2006, we deployed 41 pop-up satellite archival tags (PSATs) on adult Atlantic bluefin tuna off the coast of Nova Scotia, Canada, and on Georges Bank. During the assumed spawning period, 56% of the tagged ABFT occupied a known spawning area, while 44% were located in distant oceanic regions. Assuming obligate annual spawning, these results are inconsistent with the notion of spawning site fidelity to the Gulf of Mexico. The ocean-wide migrations of adult ABFT tagged on a common forage ground suggest evidence of a metapopulation requiring more spatially explicit management than the current simple two-stock structure.