The genetic structure of raccoon introduced in Central Europe reflects multiple invasion pathways

Invasions of non-native species are of great concern as they have a devastating impact on native biodiversity and can also affect the economy of a region. Multiple introductions in several locations of a new range greatly promote the success of non-native species. The raccoon (Procyon lotor) is an omnivore whose native distribution extends from southern Canada to Panama. It has been successfully introduced in many European countries. We examined the microsatellite and mitochondrial diversity of raccoon populations in Central Europe (Germany, Poland, and Czech Republic) in order to determine their introduction sources and pathways as well as the factors affecting genetic structure in this invasive species. We found low diversity of the mtDNA control region and moderate diversity of microsatellite markers. Raccoon showed three hierarchic levels of genetic structure which separate at different levels sampled from Czech Republic, Germany and raccoon inhabiting two different habitats in Poland. In Poland the raccoon population was established through migration from Germany to Czech Republic. Analysis of the intensity of migration between two different habitat types indicated source-sink dynamics in the Polish populations of raccoons. Our results confirm the high intensity of the raccoon invasion in Central Europe and point to specific measures needed as part of an effective management strategy.