title: Temporally stable population-specific differences in run timing of one-sea-winter Atlantic salmon returning to a large river system.
abstract: The understanding of migration patterns can significantly contribute to conservation and management. The spawning migrations of Atlantic salmon (Salmo salar) cover thousands of kilometers from the feeding areas at sea to their natal rivers to reproduce. Migrating salmon are exposed to intensive harvest, but little is known of the population-specific differences in migration behavior. In this study, timing of return migration was investigated among one-sea-winter Atlantic salmon within a river system. By utilizing knowledge of the genetic population structure, population of origin was reliably identified for c. 1500 fish caught in mixed stock fisheries after adopting an approach to minimize the complications arising from potential nonsampled populations. Results demonstrated significant and temporally stable differences among populations as well as between sexes. Generally, female salmon from tributary populations entered fresh water first. Run timing was not however related to in-river migration distance. Rather, one-sea-winter salmon from larger populations and with a higher proportion of multi-sea-winter females arrived later in the season. These findings are a significant step toward a more thorough understanding of the salmon migration behavior and behavioral ecology, providing concrete tools for the management and conservation of the remaining indigenous Atlantic salmon stocks.
authors.affiliation: Department of Biology, University of Turku Turku, Finland.
authors.forename: Juha-Pekka
authors.initials: JP
authors.lastname: Vähä
authors.affiliation: Finnish Game and Fisheries Research Institute Oulu, Finland.
authors.forename: Jaakko
authors.initials: J
authors.lastname: Erkinaro
authors.affiliation: Finnish Game and Fisheries Research Institute Oulu, Finland.
authors.forename: Eero
authors.initials: E
authors.lastname: Niemelä
authors.affiliation: Department of Biology, University of Turku Turku, Finland.
authors.forename: Craig R
authors.initials: CR
authors.lastname: Primmer
authors.affiliation: Department of Biology, University of Turku Turku, Finland.
authors.forename: Irma
authors.initials: I
authors.lastname: Saloniemi
authors.affiliation: Department of Arctic and Marine Biology, University of Tromsø Tromsø, Norway ; Department of Arctic Ecology, Polar Environmental Center, Norwegian Institute for Nature Research Tromsø, Norway.
authors.forename: Morten
authors.initials: M
authors.lastname: Johansen
authors.affiliation: Department of Arctic Ecology, Polar Environmental Center, Norwegian Institute for Nature Research Tromsø, Norway.
authors.forename: Martin
authors.initials: M
authors.lastname: Svenning
authors.affiliation: Department of Environmental Affairs, Office of the County Governor of Finnmark Vadsø, Norway.
authors.forename: Sturla
authors.initials: S
authors.lastname: Brørs
keywords: Salmo salar; behavior; exploitation; fisheries management; genetic stock identification; life history; spawning migration