Ravache A. auteur aut IRD Bourgeois K. auteur aut IRD Thibault Martin auteur aut IRD Dromzée S. auteur aut IRD Weimerskirch H. auteur aut IRD de Grissac S. auteur aut IRD Prudor A. auteur aut IRD Lorrain Anne auteur aut IRD Menkès Christophe auteur aut IRD Allain V. auteur aut IRD Bustamante P. auteur aut IRD Letourneur Y. auteur aut IRD Vidal Eric auteur aut IRD text journalArticle eng text/pdf born digital access Lunar phase and illumination are known to affect nocturnal behavior of many organisms, particularly through predator-prey interactions. Visual predators can benefit from higher light levels to increase their activity, while prey may decrease their activity to avoid predation. The lower number of nocturnal seabirds observed on colonies during full moon nights has been mostly interpreted as a predation avoidance strategy. However, it is also possible that shearwaters take advantage of the moon's illumination to feed also at night, and stay at sea to forage during full moon nights. We used miniaturized GPS-loggers to obtain 179 tracks from 99 wedge-tailed shearwaters breeding in New Caledonia, to investigate moonlight effects on individual behavior. Lunar phase significantly predicted self-provisioning trip duration, with individuals performing longer trips around the full moon. However, this relationship was not significant during chick-provisioning trips when adults have to frequently return to the colony. Adults mostly returned to the colony during moonlit periods, refuting the predation avoidance theory. Tracked individuals showed an unexpectedly high amount of nocturnal foraging activity (28% of total activity), positively influenced by the presence of the moon. δ15N stable isotope values were significantly related to the percentage of nocturnal foraging, but with a weak relationship, impeding our ability to confirm that wedge-tailed shearwaters fed on different prey when foraging at night. This study suggests that reduced colony attendance around the full moon may be linked to greater at-sea foraging opportunities in distant oceanic areas than to increased predation risk on land specialized NOUVELLE CALEDONIE MER DE CORAIL PACIFIQUE 034BIOVER03 080ZOOGEN 525 art.151322 [9 ] 2020 0022-0981 https://www.documentation.ird.fr/hor/fdi:010078443 10.1016/j.jembe.2020.151322 0022-0981 [F B010078443] https://www.documentation.ird.fr/hor/fdi:010078443 https://www.documentation.ird.fr/intranet/publi/depot/2020-03-30/010078443.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2020-03-16 2025-02-24 fdi:010078443 fre