Windscapes shape seabird instantaneous energy costs but adult behavior buffers impact on offspring

• Published in: Movement Ecology
• Main Authors: H. Elliott, Kyle, S. Chivers, Lorraine, Bessey, Lauren, J. Gaston, Anthony, A. Hatch, Scott, Kato, Akiko, Osborne, Orla, Ropert‐coudert, Yan, R. Speakman, John, F. Hare, James
• Other Authors: Department of Biological Sciences Winnipeg, University of Manitoba Winnipeg, The Buntings, National Wildlife Research Center, Environment and Climate Change Canada, Institute for Searbird Research and Conservation, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institute of Environmental and Biological Sciences, University of Aberdeen, Key State Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Changchun Branch (CAS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: [SDE]Environmental Sciences; [SDV]Life Sciences [q-bio]; Black-legged Kittiwake; rissa tridactyla; thick-billed murre; Uria lomvia; uria
• Online Access: https://hal.science/hal-01068796; https://hal.science/hal-01068796/document; https://hal.science/hal-01068796/file/s40462-014-0017-2.pdf; https://doi.org/10.1186/s40462-014-0017-2

International audience Background: Windscapes affect energy costs for flying animals, but animals can adjust their behavior to accommodate wind-induced energy costs. Theory predicts that flying animals should decrease air speed to compensate for increased tailwind speed and increase air speed to compensate for increased crosswind speed. In addition, animals are expected to vary their foraging effort in time and space to maximize energy efficiency across variable windscapes. Results: We examined the influence of wind on seabird (thick-billed murre Uria lomvia and black-legged kittiwake Rissa tridactyla) foraging behavior. Airspeed and mechanical flight costs (dynamic body acceleration and wing beat frequency) increased with headwind speed during commuting flights. As predicted, birds adjusted their airspeed to compensate for crosswinds and to reduce the effect of a headwind, but they could not completely compensate for the latter. As we were able to account for the effect of sampling frequency and wind speed, we accurately estimated commuting flight speed with no wind as 16.6 ms−1 (murres) and 10.6 ms−1 (kittiwakes). High winds decreased delivery rates of schooling fish (murres), energy (murres) and food (kittiwakes) but did not impact daily energy expenditure or chick growth rates. During high winds, murres switched from feeding their offspring with schooling fish, which required substantial above-water searching, to amphipods, which required less above-water searching. Conclusions: Adults buffered the adverse effect of high winds on chick growth rates by switching to other food sources during windy days or increasing food delivery rates when weather improved.