Diet of the soft-plumaged petrel (Pterodroma mollis) at Kerguelen Islands and a review of the food of gadfly petrels (Pterodroma spp.) worldwide

• Published in: Marine Biology
• Main Authors: Cherel, Yves, Bocher, Pierrick
• Other Authors: Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), LIttoral ENvironnement et Sociétés - UMR 7266 (LIENSs), Institut national des sciences de l'Univers (INSU - CNRS)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: Fish; Food; Myctophidae; Procellariiformes; Seabirds; Southern Ocean; Squid; Tropics; [SDE]Environmental Sciences; Kerguelen; Kerguelen Islands
• Online Access: https://hal.science/hal-03539068; https://doi.org/10.1007/s00227-022-04019-w

International audience Little is known on the food and feeding ecology of the soft-plumaged petrel Pterodroma mollis, which is the single gadflypetrel Pterodroma spp. with a circumpolar breeding distribution within the Southern Ocean. Our primary goal was to describeits diet at Kerguelen Islands, which is the southernmost breeding locality of the species. Soft-plumaged petrels fed on fish(71% by mass), and secondarily on crustaceans (22%), while cephalopods (7%) and other items (< 1%) were minor dietarycomponents. Eight-hundred and sixty prey were identified from the pooled 33 food samples, with the 2 hyperiid amphipodsCyllopus magellanicus (48%) and Themisto gaudichaudii (35%) being the main food items by number. Owing to their largersize than crustaceans, mesopelagic fishes were the main prey by mass, with myctophids being the most important fish familyin terms of both abundance (68% of the fish) and diversity (10 species). Prey distribution indicated that soft-plumagedpetrels foraged primarily in oceanic subantarctic waters to feed their chicks. The oceanic life style of gadfly petrels was thenhighlighted by a review of their diet worldwide (20 species, 26 studies). Gadfly petrels prey mainly upon mesopelagic fishes(chiefly myctophids) and squids with their relative proportions depending on species and localities. Crustaceans are minorfood items for tropical species, but they form a significant part of the food of the small- and medium-sized petrels that live intemperate and cold waters. The review underlines the need for more well-designed investigations on this globally endangeredgroup of seabirds, since dietary information is available for only 57% of the 35 species of gadfly petrels.