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Fragmentation of forest landscapes and structural degradation of woodlands have a holistic negative effect on biodiversity. Bats are considered as indicators of woodland’s structural quality. However, as bats commute long distances on a nightly basis, their diversity should also be limited by large-scale drivers such as landscape and species availability in the region. Therefore we examined roles of the local species pool, landscape structure and habitat properties on species richness of bats through three spatial scales with emphasis on top–down relationships. Our aim for conservation ecology was to evaluate habitat quality and the importance of stand origin, i.e. contrast between mature forests and old parks. Bats were surveyed in 28 landscape windows, which consisted of at least one park and forest site. In total we sampled 63 deciduous woodlands in Estonia. In each site we sampled two microhabitats: edge and stand interior. Bat species richness was mostly explained by large-scale drivers, such as local species pool and landscape composition within 1 km radius. Stand properties had a weaker effect, driven by understory clutter. At the finest scale, the importance of edge habitats was emphasized by greater species richness at the edge in comparison to the stand interior and the edge’s predictive power on species richness in the stand interior. Habitat origin (park vs. forest) was an important aspect only for small-scale species richness, specifically in woodland interiors. The conservation policy of woodland bats should be based on complex multi-scale planning, in which natural and anthropogenic woodlands can be considered as a single land-cover type. To provide optimal foraging habitat for bats, the forest landscape should be diversified with integrated small waterbodies and canopy gaps with sharp edges.
