Insectivorous Bats Provide More Services than Disservices in China

Abstract

Bats provide vital ecosystem services, especially in controlling pests. Most studies have paid attention to the diet composition of bats. However, whether the prey is beneficial or harmful to humans is unknown, which makes it difficult to objectively assess the services provided by bats. To address this issue, we collected individuals of 10 species of bats and their fecal samples from three sampling sites and performed DNA metabarcoding to identify the diet composition of bats. We categorized prey as harmful or beneficial based on previous studies. Our results showed that insectivorous bats have a broad diet. The 10 bat species consumed 19 orders and 96 families of prey, most of which were lepidopterans. Among the 564 prey items identified at least up to the family level, 390 (69.15%) pests and 28 (4.96%) beneficial insects were predated by bats, and 326 (57.80%) pests affected agriculture and forestry; some of these pests included Cotton bollworm (Helicoverpa armigera) and Beet armyworm (Spodoptera exigua). Previous qualitative studies focused on the dietary composition of bats, whereas our quantitative study showed that bats have more beneficial effects than harmful effects. Our study provided strong evidence for researchers to promote the value of bats and inform farmers about the services bats provide to agroforestry. We also developed a script file that can automatically classify OTUs, which can help researchers perform dietary analysis.

Keywords: Bats, agriculture, pest control, ecosystem services, Metabarcoding, Dietary analysis