Bat-mediated pest regulation in understudied pasture agroecosystems

Pastureland provides critical resources for livestock production. Despite the growing knowledge on pest regulating services provided by insectivorous bats, their role in pastureland systems remains understudied. We analysed the diets of four Irish bat species, Plecotus auritus, Pipistrellus pygmaeus, Myotis nattereri, and Rhinolophus hipposideros, to identify and categorise agricultural pest species based on metabarcoding studies in the pastureland rich agro-ecosystems of Ireland. Pest richness varied among bat species, with P. auritus consuming 22 known pest species, 13 in P. pygmaeus, 9 in R. hipposideros, and 7 in M. nattereri. Pest occurrence frequency varied in overall diets: R. hipposideros exhibited the highest (83%), followed by P. auritus (71%), M. nattereri (59%), and P. pygmaeus (32%). Importantly, 26 of the 35 pest species (74%) were consumed by only one bat species. Key pastureland pests, Tipula oleracea and T. paludosa, were detected across all bat species, with frequency of occurrence reaching up to 100% at several roosts. Livestock-associated disease vectors (Culicoides scoticus and C. pulicaris) were also consumed. Differences in diet among species reflect complementary foraging strategies, activity patterns, and habitat use, highlighting the collective role of bat communities in pest regulation. These findings provide additional evidence that insectivorous bats contribute to ecosystem services in pasturelands, potentially supporting reductions in pesticide use and enhancing sustainable pastureland management. By demonstrating the functional importance of bats beyond biodiversity conservation, this study underscores their value in nature-based solutions for sustainable agriculture and informs conservation and policy strategies in Ireland. Highlights- Clear habitat bias in studies of ecosystem services by insectivorous bats. - Bat species forage on diverse agricultural pests in pastureland-dominated areas. - Bat foraging behaviour influences consumption of specific pest species. - Bats consume major pasture pests, Tipula oleracea and T. paludosa. - Different bat species target different pests, enhancing overall control.