Consequences of dispersal on Atlantic salmon metapopulation persistence and dynamics of local populations

• Main Author: Lamarins, Amaia
• Other Authors: Ecologie Comportementale et Biologie des Populations de Poissons (ECOBIOP), Institut National de la Recherche Agronomique (INRA)-Université de Pau et des Pays de l'Adour (UPPA), Université de Pau et des Pays de l'Adour (UPPA), FRA., Mathieu Buoro, Stéphanie Carlson
• Format: Master Thesis
• Language: French
• Published: HAL CCSD 2019
• Subjects: Spatial dispersal; Metapopulation; Persistence of local population; Local population dynamics; Atlantic salmon (Salmo salar); Individual-based model; Salmonids; Population dynamics; Dispersion spatiale; Métapopulation; Persistance de la population locale; Dynamique des populations locales; Saumon atlantique (Salmo salar); Modèle individu-centré; Salmonidés; [SDE]Environmental Sciences; [SDV.BA]Life Sciences [q-bio]/Animal biology; Atlantic salmon; Salmo salar
• Online Access: https://dumas.ccsd.cnrs.fr/dumas-03829871; https://dumas.ccsd.cnrs.fr/dumas-03829871/document; https://dumas.ccsd.cnrs.fr/dumas-03829871/file/2018-2019.DYNEA.M2.Lamarins.Ama%C3%AFa.pdf

Master Spatial dispersal is a ubiquitous trait in organisms. It is central in the theory of metapopulations, with potential consequences on their stability and persistence, as well as on local population dynamics. Although dispersal and metapopulation functioning have been suggested for salmonid, the consequences of dispersal are still underappreciated, likely because assessing dispersal in nature is challenging. We used a demo-genetic individual-based model mimicking an Atlantic salmon metapopulation connected by a distance dispersal kernel. Our model depicts a complex relationship between dispersal and the metapopulation portfolio effect. In particular, we show that low dispersal rates favor metapopulation stability, via the demographic rescue of small populations and stabilizing effects of dispersal. However, higher dispersal rates tend to synchronize populations, leading to anti-rescue effects. We also show density-dependent effects of dispersal on local populations, especially in sink ones, with consequences on life-history strategies and especially age at maturation, mainly via phenotypic plasticity. Altogether, we suggest that the spatial structure of Atlantic salmon populations should be considered in management and conservation strategies because the dynamics of local populations rely on the whole metapopulation functioning via spatial dispersal. La dispersión espacial es un rasgo ubicuo en los organismos. Es central en la teoría de las metapoblaciones, con posibles consecuencias sobre su estabilidad y persistencia, así como sobre la dinámica de la población local. Aunque la dispersión y el funcionamiento de la metapoblación se han sugerido para los salmónidos, las consecuencias de la dispersión siguen siendo subestimadas, probablemente porque evaluar la dispersión en la naturaleza es difícil. Usamos un modelo demo-genético individual-centrado imitando una metapoblación de salmón atlántico conectada por un kernel de dispersión por distancia. Nuestro modelo representa una relación compleja entre la ...