Pest control services provided by bats in vineyard landscapes

Abstract

Faced with current health and environmental challenges, viticulture is directly concerned with the need to reduce pesticide use. Natural pest control services provided by bats have been demonstrated in other crops and is regularly mentioned as a way to reduce pesticide use. However, the trophic link between bats and grape pests as well as the effect of pest presence on bat activities remain largely unknown. To investigate the functional role of bats in vineyard landscapes, we used two independent approaches. We monitored the activities of bats and of the European grapevine moth (Lobesia botrana) in 23 vineyards located in the Bordeaux region (France). In parallel, we developed DNA primers to examine bat faeces from two regions, Bordeaux and Burgundy, for the presence of the three main species of grapevine moths. Our results demonstrate that bats significantly increase their hunting activity when European grapevine moths are present in vineyards. In addition, our molecular analysis of the faeces provides robust evidence that at least 10 species of bats predate the three grapevine moth species. Our results therefore suggest that bats can be natural enemies of grape pests in vineyard landscapes. Further research is now needed to investigate the consequences of predation of pests by bats on crop production as well as the effect of some management options at both the local and landscape scale to increase the level of pest control services provided by bats.