title: Genetic and phenotypic changes in an Atlantic salmon population supplemented with non-local individuals: a longitudinal study over 21 years.
abstract: While introductions and supplementations using non-native and potentially domesticated individuals may have dramatic evolutionary effects on wild populations, few studies documented the evolution of genetic diversity and life-history traits in supplemented populations. Here, we investigated year-to-year changes from 1989 to 2009 in genetic admixture at 15 microsatellite loci and in phenotypic traits in an Atlantic salmon (Salmo salar) population stocked during the first decade of this period with two genetically and phenotypically distinct source populations. We detected a pattern of temporally increasing introgressive hybridization between the stocked population and both source populations. The proportion of fish returning to the river after a single winter at sea (versus several ones) was higher in fish assigned to the main source population than in local individuals. Moreover, during the first decade of the study, both single-sea-winter and multi-sea-winter (MSW) fish assigned to the main source population were smaller than local fish. During the second decade of the study, MSW fish defined as hybrids were lighter and smaller than fish from parental populations, suggesting outbreeding depression. Overall, this study suggests that supplementation with non-local individuals may alter not only the genetic diversity of wild populations but also life-history traits of adaptive significance.
authors.affiliation: INRA, UMR 0985 Ecology and Health of Ecosystems, Rennes 35042, France Agrocampus Ouest, 65 Rue de Saint-Brieuc, Rennes 35042, France Station Biologique de Roscoff, Place Georges Teissier, Sorbonne Universités, UPMC Univ Paris 06, UMR 7144, Roscoff Cedex 29688, France Station Biologique de Roscoff, Place Georges Teissier, CNRS, UMR 7144, Roscoff Cedex 29688, France sablecam15@gmail.com.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Le Cam
authors.affiliation: Département de Biologie, Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Canada.
authors.forename: Charles
authors.initials: C
authors.lastname: Perrier
authors.affiliation: INRA, UMR 0985 Ecology and Health of Ecosystems, Rennes 35042, France Agrocampus Ouest, 65 Rue de Saint-Brieuc, Rennes 35042, France.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Besnard
authors.affiliation: Département de Biologie, Institut de Biologie Intégrative et des Systèmes, Université Laval, Québec, Canada.
authors.forename: Louis
authors.initials: L
authors.lastname: Bernatchez
authors.affiliation: INRA, UMR 0985 Ecology and Health of Ecosystems, Rennes 35042, France Agrocampus Ouest, 65 Rue de Saint-Brieuc, Rennes 35042, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Evanno
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D005075:Biological Evolution; D014644:Genetic Variation; D006824:Hybridization, Genetic; D008137:Longitudinal Studies; D018895:Microsatellite Repeats; D010641:Phenotype; D045483:Rivers; D020317:Salmo salar / Q000235:genetics*
keywords: Salmo salar; genetic admixture; introgressive hybridization; life-history traits; outbreeding depression; stocking