Genetic and morphological sex identification methods reveal a male-biased sex ratio in the Ivory Gull Pagophila eburnea

• Published in: Journal of Ornithology
• Main Authors: Yannic, Glenn, Broquet, Thomas, Strøm, Hallvard, Aebischer, Adrian, Dufresnes, Christophe, Gavrilo, Maria V., Grant Gilchrist, H., Mallory, Mark L., Guy Morrison, R. I., Sabard, Brigitte, Sermier, Roberto, Gilg, Olivier
• Other Authors: Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ), Groupe de Recherche en Ecologie Arctique, DIVersité et COnnectivité dans le paysage marin côtier (DIVCO), Adaptation et diversité en milieu marin (AD2M), Station biologique de Roscoff Roscoff (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Station biologique de Roscoff Roscoff (SBR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Norwegian Polar Institute, Department of Ecology and Evolution Lausanne, Université de Lausanne (UNIL), National Park Russian Arctic, Joint Directorate of Taimyr Nature Reserves, Environment and Climate Change Canada, Acadia University, Biogéosciences UMR 6282 Dijon (BGS), Centre National de la Recherche Scientifique (CNRS)-Université de Bourgogne (UB)-AgroSup Dijon - Institut National Supérieur des Sciences Agronomiques, de l'Alimentation et de l'Environnement
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2016
• Subjects: Sexual dimorphism; Noninvasive sampling; Molecular sexing; Morphological sexing; Buccal swab; [SDV.BA.ZV]Life Sciences [q-bio]/Animal biology/Vertebrate Zoology; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; Arctic; Greenland; Svalbard; ivory gull; Pagophila eburnea; Sea ice
• Online Access: https://hal.sorbonne-universite.fr/hal-01333970; https://hal.sorbonne-universite.fr/hal-01333970/document; https://hal.sorbonne-universite.fr/hal-01333970/file/Yannic_2016_Genetic_and.pdf; https://doi.org/10.1007/s10336-016-1328-4

International audience Sex identification of birds is relevant to studies of evolutionary biology and ecology and is often a central issue for the management and conservation of populations. The Ivory Gull Pagophila eburnea (Phipps, 1774) is a rare high-Arctic species whose main habitat is sea ice throughout the year. This species is currently listed Near Threatened by the IUCN, because populations have drastically declined in part of the species distribution in the recent past. Here we tested molecular sexing methods with different types of samples. Molecular sexing appeared to be very efficient with DNA extracted from muscle, blood, and buccal swabs, both for adults and young chicks. We also performed morphological analyses to characterize sexual size dimorphism in Ivory Gulls sampled in three distinct regions: Greenland, Svalbard, and Russia. Males were larger than females for all morphometric measurements, with little overlap between sexes. Discriminant analysis based on six morphometric variables correctly classified ~95 % of the individuals, even when using two variables only, i.e., gonys height and skull length. Therefore, both molecular and biometric methods are useful for sexing Ivory Gulls. Interestingly, our results indicate a male-biased sex ratio across all Ivory Gull populations studied, including two samples of offspring (67.8 % males).