Foraging tactics in dynamic sea‐ice habitats affect individual state in a long‐ranging seabird

• Published in: Functional Ecology
• Main Authors: Tarroux, Arnaud, Cherel, Yves, Fauchald, Per, Kato, Akiko, Love, Oliver, Ropert‐Coudert, Yan, Spreen, Gunnar, Varpe, Øystein, Weimerskirch, Henri, Yoccoz, Nigel, Zahn, Sandrine, Descamps, Sébastien
• Other Authors: Norvegian Polar Research Institute (NPRI), Norwegian Polar Institute, Norwegian Institute for Nature Research (NINA), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Department of Biological Sciences Canada (University of Windsor), University of Windsor Ca, University of Bremen, Akvaplan-Niva Tromsø, Norwegian Institute for Water Research (NIVA), Arctic University of Norway, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2020
• Subjects: Antarctic petrel; GPS tracking; individual variation; optimal foraging; physiological indicators; Southern Ocean; stable isotopes; Svarthamaren breeding colony; [SDE]Environmental Sciences; Antarctic; Svarthamaren; The Antarctic; Antarc*; Antarctic Petrel; Antarctica; Sea ice; Thalassoica antarctica
• Online Access: https://hal.archives-ouvertes.fr/hal-02912933; https://doi.org/10.1111/1365-2435.13632

International audience 1. Individual heterogeneity in diet and foraging behaviour is common in wild animalpopulations, and can be a strong determinant of how populations respond toenvironmental changes. Within populations, variation in foraging behaviour andthe occurrence of individual tactics in relation to resources distribution can helpexplain differences in individual fitness, and ultimately identify important factorsaffecting population dynamics. We examined how foraging behaviour and habitatduring the breeding period related to the physiological state of a long-rangingseabird adapted to sea ice, the Antarctic petrel Thalassoica antarctica.2. Firstly, using GPS tracking and state-switching movement modelling (hidden Markovmodels) on 124 individual birds, we tested for the occurrence of distinct foraging tacticswithin our study population. Our results highlight a large variation in the movementand foraging behaviour of a very mobile seabird, and delineate distinct foragingtactics along a gradient from foraging in dense pack ice to foraging in open water.3. Secondly, we investigated the effects of these foraging tactics on individual stateat return from a foraging trip. We combined movement data with morphometricand physiological measurements of a suite of plasma metabolites that provideda general picture of a bird's individual state. Foraging in denser sea ice was associatedwith lower gain in body mass during brooding, as well as lower level ofenergy acquisition (plasma triacylglycerol) during both brooding and incubation.We found no clear relationship between the foraging tactic in relation to sea iceand the energetic stress (changes in plasma corticosterone), energetic balance(β-hydroxybutyrate) or trophic level (δ15N). However, a shorter foraging range wasrelated to both the energetic balance (positively) and the trophic level (negatively).4. Our results highlight a diverse range of foraging tactics in relation to sea ice inAntarctic petrels. While the various foraging tactics do not seem to ...