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Agricultural intensification was a major driver of declines in western European wildlife populations during the twentieth century, including those of bats. Agri-environment schemes are advocated as the key government-funded mechanism to restore biodiversity, but evidence for their effects has been mixed. We examined the response of six bat species to Tir Gofal (TG), a Welsh AES that operated from 1999 to 2011. A large-scale multi-site study compared bat activity and key habitat variables on TG farms paired with control farms not in the scheme. Observations were made over three years (2009 to 2011) using three types of bat detector survey. Pipistrellus pipistrellus, P. pygmaeus, Myotis daubentonii, Rhinolophus hipposideros and R. ferrumequinum showed similar overall and foraging activity on TG and control farms (occurrence, intensity of activity where present). Occurrence of Nyctalus noctula and Nyctalus group was also similar on both farm types, but where they were present, the intensity of their activity was higher on control farms. The lack of influence of TG status on bat activity may reflect the close similarity in occurrence and condition of many key habitats on the two farm types and should be seen in the context of a mainly traditional extensively farmed landscape. Habitat prescriptions may have been insufficiently mature, implemented at too low density or lacking roosting provision to stimulate a species response, or may have had greater impact in a more intensively farmed landscape where less high quality bat habitat was available. A more targeted approach to creating and enhancing field and landscape scale roosting, foraging and commuting resources may be needed to effect positive responses in bat populations.

Social structure evolves from a trade-off between the costs and benefits of group-living, which are in turn dependent upon the distribution of key resources such as food and shelter. Males and females, or juveniles and adults, may have different priorities when selecting habitat due to differences in physiological or behavioural imperatives, leading to complex patterns in group composition. We studied social structure and mating behaviour in the insectivorous bat Myotis daubentonii along an altitudinal gradient, combining field studies with molecular genetics. With increasing altitude the proportion of males in summer roosts increased and only males were present in the highest roosts. With increasing altitude environmental temperature decreased, nightly variation in temperature increased, and bat foraging activity decreased, supporting the hypothesis that the harsher, high elevation sites cannot support breeding females. We found that offspring in female-dominated lowland roosts had a very high probability of being fathered by bats caught during autumn swarming at hibernation sites, in contrast to those in intermediate roosts, which had a high probability of being fathered by males sharing the nursery roost with the females. Whilst females normally appear to exclude males from nursery colonies, for those in marginal habitats, one explanation for the presence of males is that the thermoregulatory benefits to the females may outweigh disadvantages, such as competition for food, and give some males an opportunity to increase their breeding success. We suggest that the environment, and its effects on resource distribution, thus determine social structure, which in turn determines the mating pattern that has evolved.