Tidying up the cluttered understorey: Foraging strategy mediates bat activity responses to invasive rhododendron

摘要: Abstract Biological invasions pose a significant threat to biodiversity, yet the severity and direction of impacts differs between taxa. The non-native evergreen shrub Rhododendron ponticum has colonized large areas woodland understorey in UK is currently undergoing widespread clearance due its negative on native flora as potential host reservoir for harmful pathogens. Presence rhododendron significantly increases amount structural clutter and, hence, modifies microhabitat structure, which might have an impact bat foraging activity. Here, first time, we investigated effects activity British species by performing autonomous acoustic surveys at twelve sites Richmond Park, London, where was either present, absent or recently removed. other characteristics likely influence (e.g. tree diversity, canopy cover, distance water presence/absence deer) were also considered. We predicted that increased present invaded would reduce larger, less agile bats Nyctalus noctula, Eptesicus serotinus leisleri (NSL), whereas able forage within, edges of, Myotis spp. Pipistrellus spp.) not be negatively affected. While our results indicated reduction open space foragers (NSL) rhododendron-invaded areas, deer presence had stronger effect than woody understory density cover these species. Activity recorded impacted rhododendron. However, been removed demonstrated higher levels with exception pygmaeus, displayed understorey. NSL P. pipistrellus more frequent commuting/roosting without rhododendron, although pygmaeus appeared regularly utilising least some this purpose. To mitigate removal species, therefore suggest restriction access enable recovery