Spatially restricted gene flow and reduced microsatellite polymorphism in the Eurasian otter Lutra lutra in Britain

摘要: Although gene flow and population fragmentationwill often have opposed effects on geneticstructure, their actual many elusiveanimal species are unknown. We assessed sucheffects in British populations of the Eurasianotter Lutra lutra by analysis ofgenotypes consisting 12 microsatellites from618 carcasses representing period 1982–1998. Spatial patterns genetic subdivisionand levels polymorphism continuouspopulation Scotland were estimated. Theseresults used to infer geneflow Scottish otters assess theinfluence fragmentation geneticstructure Wales SW England.The latter showed no higher divergencethan expected given degree isolation bydistance found population, andtheir distributions microsatellite allelesizes provided evidence for populationbottlenecks. Nonetheless, southernBritain contained significantly lower ofmicrosatellite than inScotland, westernpeninsula England was geneticallydistinct. These results suggested that thegenetic structure isdue more restricted contemporary flowthan historical fluctuations insubpopulation size, southern populationsis due small effective sizesthan recent declines. If spatiallyrestricted is typical all then data dispersal shouldbe taken into account when sitting protectedareas this species.