Habitat preferences of specialist bat are forest-type specific: western barbastelle in natural temperate woodlands

Abstract Understanding the species-habitat relationships of forest specialists is an essential challenge in their effective conservation. However, studies on habitat selection often neglect potential context dependence, even though species performance may differ between natural and managed stands or between forests composed of different tree species. The western barbastelle Barbastella barbastellus, a specialized moth predator and an old-growth forest indicator, is known to rely on fine-scale habitat structures and forest complexity, yet the relative importance of habitat traits across different forest types remains poorly understood. We surveyed the species on 150 plots distributed across five the best-preserved temperate forest types in Poland: spruce, beech, beech–fir, oak–lime–hornbeam and willow–poplar forests. Bat presence was quantified using passive acoustic monitoring, and habitat characteristics were derived from LiDAR, stand inventories and surveys of tree-related microhabitats. We identified canopy gaps, tree height complexity, living tree density and density of trees with insect galleries or cankers, as the best predictors of the species presence, although the strength of these relationships varied among forest types. In single-species stands, the occurrence of the western barbastelle was associated with abundance of canopy gap and complexity of tree heights, whereas in forests with more diverse tree species composition, the relationships with the stand structure were less evident and were replaced by stronger association with fine-scale habitat components such as tree-related microhabitats. Synthesis and applications. Our study demonstrates that the effective conservation of forest specialists requires habitat-specific strategies, because no single habitat variable predicts species occurrence across contrasting forest conditions. For the western barbastelle, conservation actions should involve maintaining small canopy gaps and reduced tree height complexity in single-species stands, while preserving high heterogeneity, i.e. diverse age and size tree classes and high tree species richness in mixed forests. For a large group of forest specialist, strategies tailored to forest type, rather than a one-size-fits-all approach, should be considered. Competing Interest Statement The authors have declared no competing interest.