Green land in a landscape bolsters the dietary diversity of reared yellow-legged hornet Vespa velutina Lepeletier (Hymenoptera: Vespidae).

Abstract

Land use change has significantly altered most ecosystem functioning, such as nutrition provisioning, water flows and pollination services. So far, the impact of land use change on the dietary diversity of predatory insects has remained largely unexplored. In this study, we explored the prey composition of reared yellow-legged hornets Vespa velutina Lepeletier (Hymenoptera: Vespidae) in landscapes with a gradient of surrounding green lands, using metabarcoding of feces eliminated by larvae. The hornets primarily fed upon insects, with dipterans, coleopterans, lepidopterans, hemipterans, hymenopterans, and orthopterans being the dominant prey groups. The percentage of green lands had a significantly positive effect on prey richness at a spatial scale of 1500 m, but no effect on Shannnon index of the prey community. Meanwhile, the green lands had significantly positive effects on richness of coleopteran prey and lepidopteran prey, but no significant effect on richness of dipteran prey, hemipteran prey, hymenopteran prey, or orthopteran prey. In terms of beta diversity, the percentage of green lands explained the dissimilarity of prey communities among landscapes, whereas local factors, such as the distance to green lands and the distance to buildings, did not explain the dissimilarity. Our study indicated that the green lands in the landscape positively affected the dietary diversity of reared yellow-legged hornets, but this effect varied among different taxonomic groups of prey.