Foraging movements of emperor penguins at Pointe Géologie, Antarctica

• Main Authors: Zimmer, Ilka, Wilson, Rory, Gilbert, Caroline, Beaulieu, Michaël, Ancel, André, Plötz, Joachim
• Other Authors: Department of Bentho-pelagic processes, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Institute of Environmental Sustainability, Swansea University, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: Foraging distribution; Central-place forager; Emperor penguin; Area-restricted-search; Foraging strategies; geo; envir; Antarctic; Pointe-Géologie; The Antarctic; Antarc*; Antarctica; Emperor penguins; Polar Biology; Sea ice
• Online Access: https://hal.archives-ouvertes.fr/hal-00357997

International audience The foraging distributions of 20 breeding emperor penguins were investigated at Pointe Ge´ologie, Terre Ade´lie, Antarctica by using satellite telemetry in 2005 and 2006 during early and late winter, as well as during late spring and summer, corresponding to incubation, early chick-brooding, late chick-rearing and the adult pre-moult period, respectively. Dive depth records of three post-egg-laying females, two post-incubating males and four late chick-rearing adults were examined, as well as the horizontal space use by these birds. Foraging ranges of chick-provisioning penguins extended over the Antarctic shelf and were constricted by winter pack-ice. During spring ice break-up, the foraging ranges rarely exceeded the shelf slope, although seawater access was apparently almost unlimited. Winter females appeared constrained in their access to open water but used fissures in the sea ice and expanded their prey search effort by expanding the horizontal search component underwater. Birds in spring however, showed higher area-restricted-search than did birds in winter. Despite different seasonal foraging strategies, chick-rearing penguins exploited similar areas as indicated by both a high ‘Area-Restricted-Search Index' and high ‘Catch Per Unit Effort'. During pre-moult trips, emperor penguins ranged much farther offshore than breeding birds, which argues for particularly profitable oceanic feeding areas which can be exploited when the time constraints imposed by having to return to a central place to provision the chick no longer apply.