Tree and landscape characteristics outweigh insect abundance in driving bat activity in West African rice fields

Abstract

The urgent need to sustainably feed a growing human population is particularly pressing in tropical regions where food security remains uncertain. Ecological intensification strategies, such as integrating nature-based solutions, can help achieve this goal by leveraging ecosystem services. Isolated trees in agricultural landscapes play a vital role in enhancing productivity and biodiversity, supporting organisms like insectivorous bats that provide pest control services. The implementation of measures to strengthen insectivorous bat populations holds significant potential to increase insect predation, suppress agricultural pests, and improve food security. Understanding how tree characteristics and surrounding landscapes influence bat foraging activity in staple tropical crops is thus essential. This study investigated how isolated trees influence the activity of bats and insects in smallholder rice fields in Guinea-Bissau. Specifically, we evaluated how tree characteristics and landscape features affect bat guild activity, insect abundance, and richness, as well as the indirect effects of insects on bats. Our findings indicate that larger, isolated trees of specific species located closer to other trees but further from wooded edges are associated with increased bat activity and richness, mediated partly by higher insect abundance. These results emphasise the ecological and agricultural importance of isolated trees in promoting biodiversity and enhancing pest suppression in agricultural landscapes.