Lithuania is on the edge of the main distribution range of the root vole (Microtus oeconomus). It was found that the trappability of M. oeconomus did not depend on the trapping effort, the number of recorded species and individuals or the species diversity. All 13 localities with proportions of M. oeconomus constituting over 30% of the small mammal community are situated in the south and west of Lithuania. Analysis of data collected over 50 years confirms that the species has become more abundant, more widespread and its distribution range has spread north and east from the south and west of the country. The main habitats for M. oeconomus in Lithuania are reedbeds, meadows, shrubby areas and shores of water bodies. Abandoned former agricultural areas create suitable habitats for the species, thus promoting its increased abundance and wider distribution.
Winter habitat use, niche breadth and overlap between the native and invasive species of medium sized predators, the red fox, pine marten and raccoon dog in particular, were studied in three landscapes with different habitat structure in Lithuania. Meadows were preferred by foxes but avoided by raccoon dogs and pine martens. Pine martens intensively used various forest habitats, whilst raccoon dogs tended to prefer swamps. The habitat niche breadth (Hurlbert’s standardized niche breadth) varied with respect to both the species and the study site. The habitat niche overlap was larger between raccoon dog and pine marten than that between raccoon dog and red fox. Our results suggest a low impact of the invasive raccoon dog on red fox and pine marten in studied landscapes.