FN Archimer Export Format PT J TI Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea BT AF BAUER, Robert FROMENTIN, Jean-Marc DEMARCQ, Herve BRISSET, Blandine BONHOMMEAU, Sylvain AS 1:1;2:1;3:2;4:1;5:1; FF 1:PDG-RBE-MARBEC-LHM;2:PDG-RBE-MARBEC;3:;4:PDG-RBE-MARBEC-LHM;5:PDG-RBE-MARBEC-LHM; C1 IFREMER Inst Francais Rech Exploitat MER, Resarch Unit Marbec Marine Biodivers Exploitat &, Sete, France. IRD, Resarch Unit Marbec Marine Biodivers Exploitat &, Sete, France. C2 IFREMER, FRANCE IRD, FRANCE SI SETE SE PDG-RBE-MARBEC-LHM PDG-RBE-MARBEC UM MARBEC IN WOS Ifremer jusqu'en 2018 DOAJ copubli-france copubli-p187 IF 3.057 TC 25 UR https://archimer.ifremer.fr/doc/00284/39481/37969.pdf https://archimer.ifremer.fr/doc/00284/39481/37970.zip LA English DT Article AB Different dolphin and tuna species have frequently been reported to aggregate in areas of high frontal activity, sometimes developing close multi-species associations to increase feeding success. Aerial surveys are a common tool to monitor the density and abundance of marine mammals, and have recently become a focus in the search for methods to provide fisheries-independent abundance indicators for tuna stock assessment. In this study, we present first density estimates corrected for availability bias of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Golf of Lions (GoL), compared with uncorrected estimates of Atlantic bluefin tuna (ABFT; Thunnus thynnus) densities from 8 years of line transect aerial surveys. The raw sighting data were further used to analyze patterns of spatial co-occurrence and density of these three top marine predators in this important feeding ground in the Northwestern Mediterranean Sea. These patterns were investigated regarding known species-specific feeding preferences and environmental characteristics (i. e. mesoscale activity) of the survey zone. ABFT was by far the most abundant species during the surveys in terms of schools and individuals, followed by striped dolphins and fin whales. However, when accounted for availability bias, schools of dolphins and fin whales were of equal density. Direct interactions of the species appeared to be the exception, but results indicate that densities, presence and core sighting locations of striped dolphins and ABFT were correlated. Core sighting areas of these species were located close to an area of high mesoscale activity (oceanic fronts and eddies). Fin whales did not show such a correlation. The results further highlight the feasibility to coordinate research efforts to explore the behaviour and abundance of the investigated species, as demanded by the Marine Strategy Framework Directive (MSFD). PY 2015 PD OCT SO Plos One SN 1932-6203 PU Public Library Science VL 10 IS 10 UT 000362961100009 DI 10.1371/journal.pone.0139218 ID 39481 ER EF