Investigating landscape scale factors shaping dung beetle communities

Dung beetles are important contributors to ecosystem services including decomposition and pest suppression. Despite their importance, we know very little about how their communities are shaped by landscape-scale factors. Landscape composition is likely to moderate their diets (i.e., types of dung available) and the potential for pesticide exposure, particularly to veterinary parasiticides. While managed pastures provide abundant resources in terms of available dung, livestock are routinely treated with parasiticides that are excreted largely unmetabolized in dung and can have dramatic non-target effects on beneficial arthropods. To explore how landscape context influences dung beetle community composition, diet, and subsequent exposure to parasiticides, we sampled dung beetle communities using baited pitfall traps in over 60 landscapes in Kentucky, spanning a gradient from high forest to high pasture. We are currently working to quantify parasiticide concentrations in their post mortem tissue and are using molecular gut content analysis to identify the food resources used. So far, we have found no difference in dung beetle abundance or diversity across the landscape gradient. However, community composition differed strongly and landscapes with more pasture contained a higher proportion of exotic species. Ongoing work to quantify diet composition and parasiticide exposure will further uncover the ways in which landscape context, diet, and parasiticide exposure may interact to shape dung beetle communities.