From fledgling to the first reproduction : ecological and evolutionary aspect of life-history traits of young long-lived seabird

• Main Author: Fay, Rémi
• Other Authors: Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Institut National de la Recherche Agronomique (INRA)-Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Université de La Rochelle, Christophe Barbraud, Henri Weimerskirch
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2017
• Subjects: Population dynamics; Survival; Life-history traits; Life-history strategy; Seabirds; Wandering albatross; Diomedea exulans; Age of first reproduction; Individual quality; Individual heterogeneity; Albatros hurleur; Oiseaux marins; Traits d’histoire de vie; Stratégie d’histoire de vie; Dynamique des populations; Survie; Reproduction; Âge de première reproduction; Qualité individuelle; Hétérogénéité individuelle; [SDV.SA]Life Sciences [q-bio]/Agricultural sciences; Wandering Albatross
• Online Access: https://tel.archives-ouvertes.fr/tel-01753455; https://tel.archives-ouvertes.fr/tel-01753455/document; https://tel.archives-ouvertes.fr/tel-01753455/file/2017Fay99056.pdf

To date, early life demographic traits have been poorly studied compare to adult traits in the vast majority of animal species. Young individuals are usually more difficult to study due to their small size, their mobile behavior and the high mortality rate that characterizes their life stage. However, the full understanding of the demographic processes requires the integration of all life stages. This lack of knowledge toward early-life stages is particularly detrimental for long lived species. Indeed for these species, the immature component represents a substantial part of the total reproductive value, having a high influence on the whole population dynamics. Hence, such limitations affect the accuracy of population projections in the context of global change and more generally our understanding of life history trait evolution. In order to fill in this gap, this PhD project focuses on early life demographic traits in a seabird species : the wandering albatross Diomedea exulans. In this very long-lived species, the immature period lasts around 10 years. Based on long-term individual monitoring and capture-recapture analyses, we estimated early-life survival and the access to reproduction according to age and sex. We also investigates the respective effects of extrinsic (e.g. climate, fisheries) and intrinsic factors (e.g. density dependence, parental effects) on these parameters. Many relationships between early-life vital rates and environmental variables have been described. From a theoretical perspective, we tested several predictions such as the canalization of life-history traits and the existence of different life-history strategies within a population. In this work, special attention was paid to demographic variations at the individual scale. Our study showed that vital rates of individuals of the same age and sex could be very different. We have linked early-life demographic traits with subsequent adult performances and identified some causes of these individual variations. Jusqu’à aujourd’hui, les ...