The feeding ecology of little auks raises questions about winter zooplankton stocks in North Atlantic surface waters

• Published in: Biology Letters
• Main Authors: Fort, Jérôme, Cherel, Yves, Harding, Ann M.A., Egevang, Carsten, Steen, Harald, Kuntz, Grégoire, Porter, Warren P, Grémillet, David
• Other Authors: Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Centre d'Études Biologiques de Chizé (CEBC), Centre National de la Recherche Scientifique (CNRS), Alaska Pacific University, Greenland Institute of Natural Resources (GINR), Norwegian Polar Institute, Department of Zoology, University of Wisconsin-Madison, DST-NRF Centre of Excellence at the Percy FitzPatrick Institute, University of Cape Town
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: seabird; marine food web; food requirements; energetic modelling; stable isotope; diving behaviour; [SDE]Environmental Sciences; Alle alle; Greenland; North Atlantic; Copepods
• Online Access: https://hal.science/hal-00527435; https://hal.science/hal-00527435/document; https://hal.science/hal-00527435/file/Fort%20et%20al_2010%20Biol%20Lett.pdf; https://doi.org/10.1098/rsbl.2010.0082

International audience Copepods are essential components of marine food webs worldwide. In the North Atlantic, they are thought to perform vertical migration and to remain at depths more than 500m during winter. We challenge this concept through a study of the winter feeding ecology of little auks (Alle alle), a highly abundant planktivorous seabird from the North Atlantic. By combining stable isotope and behavioural analyses, we strongly suggest that swarms of copepods are still available to their predators in water surface layers (less than 50m) during winter, even during short daylight periods. Using a new bioenergetic model, we estimate that the huge number (20–40 million birds) of little auks wintering off southwest Greenland consume 3600–7200 tonnes of copepods daily, strongly suggesting substantial zooplankton stocks in surface waters of the North Atlantic in the middle of the boreal winter