Tew Kai Emilie auteur aut IRD Rossi V. auteur aut IRD Sudre J. auteur aut IRD Weimerskirch H. auteur aut IRD Lopez C. auteur aut IRD Hernandez-Garcia E. auteur aut IRD Marsac Francis auteur aut IRD Garcon V. auteur aut IRD text journalArticle eng text/pdf born digital access Meso-and submesoscales (fronts, eddies, filaments) in surface ocean flow have a crucial influence on marine ecosystems. Their dynamics partly control the foraging behavior and the displacement of marine top predators (tuna, birds, turtles, and cetaceans). In this work we focus on the role of submesoscale structures in the Mozambique Channel in the distribution of a marine predator, the Great Frigatebird. Using a newly developed dynamic concept, the finite-size Lyapunov exponent (FSLE), we identified Lagrangian coherent structures (LCSs) present in the surface flow in the channel over a 2-month observation period (August and September 2003). By comparing seabird satellite positions with LCS locations, we demonstrate that frigatebirds track precisely these structures in the Mozambique Channel, providing the first evidence that a top predator is able to track these FSLE ridges to locate food patches. After comparing bird positions during long and short trips and different parts of these trips, we propose several hypotheses to understand how frigatebirds can follow these LCSs. The birds might use visual and/or olfactory cues and/or atmospheric current changes over the structures to move along these biologic corridors. The birds being often associated with tuna schools around foraging areas, a thorough comprehension of their foraging behavior and movement during the breeding season is crucial not only to seabird ecology but also to an appropriate ecosystemic approach to fisheries in the channel. specialized frigatebird finite-size Lyapunov exponent Mozambique Channel submesoscale 036 106 20 8245-8250 2009 0027-8424 https://www.documentation.ird.fr/hor/fdi:010046092 10.1073/pnas.0811034106 0027-8424 [F B010046092] https://www.documentation.ird.fr/hor/fdi:010046092 https://www.documentation.ird.fr/intranet/publi/2009/06/010046092.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2009-07-08 2017-08-23 fdi:010046092 fre