Contributions of agri-environment schemes to the conservation of bats and their insect prey in farml

Jérémy Froidevaux

Declines of biodiversity in European farmland ecosystems have been substantially attributed to agricultural intensification. Agri-Environment Schemes (AESs) have been introduced and promoted by the European Union to address this issue, yet their effectiveness has been questioned and still remains to be tested for many taxa including bats (Chiroptera). Through my PhD thesis I aimed to (i) assess the effectiveness of targeted AESs in promoting bats and their prey in farmland habitats at multiple spatial scales; (ii) determine the influence of different landscape attributes on these taxa; and (iii) provide evidence-based conservation actions. I first investigated whether hedgerow management prescribed by targeted AESs to improve habitat conditions for the greater horseshoe bat (Rhinolophus ferrumequinum) in England may positively influence the species, the entire bat assemblage and the insect prey of bats. My results provided ample empirical evidence that targeted AESs may benefit both target and non-target species and therefore highlighted the wider biodiversity benefits of the schemes evaluated. Given that large-scale studies are needed to ascertain that outcomes of farm-scales studies could be translated to the population level, I then examined the role of AESs in driving population recovery of R. ferrumequinum in the United Kingdom. I found that the recent rise in R. ferrumequinum numbers is more likely to be attributed to climate change rather than AESs. Nevertheless, my results also indicated that the conservation of essential landscape elements through the AESs may have partly contributed to the population recovery in the long-term.