Common bats are more abundant within Natura 2000 areas

The Natura 2000 network is the largest conservation effort in Europe. However, despite the known importance of conserving common and widespread biodiversity, criteria used to designate a Natura 2000 site are oriented toward rare and/or emblematic biodiversity. In this study, we took advantage of the fact that the management of Natura 2000 is just beginning to assess whether the five most common bat (Chiroptera) species and one genus in France exhibit a greater relative abundance within rather than outside Natura 2000 boundaries, and three bats communities index: total relative abundance, species richness, Community Habitat specialization index. We model the relative abundance of each taxa and indices using data from a nationwide volunteer-based acoustic survey. We found that three of the six taxa studied exhibit greater relative abundance within Natura 2000 sites (this increase is noteworthy for E. serotinus (× 2.1) and Myotis ssp. (× 3.6)). We also provide evidence that total relative abundance of bat activity and richness are globally higher in Natura 2000 sites (respectively + 24% and + 14%) and on average communities are more specialized within Natura 2000 sites. In addition, when the effect of Natura 2000 is adjusted to the main land use types, a significant positive effect of Natura 2000 remains for most metrics. The positive Natura 2000 effect appears relatively small compared to the main land use pressure: intensive agriculture and artificial light at night. However, Natura 2000 has a comparable sized effect as habitat widely recognized as having a positive impact on bats, such as streams.