Local management actions override farming systems in determining dung beetle species richness, abundance and biomass and associated ecosystem services.

Organic farming systems have been proposed to support higher biodiversity than conventional ones, and higher diversity might make ecosystems more resilient against environmental change. We investigated how dung beetle communities and associated ecological functions (dung removal) vary at two hierarchical levels among Swedish dairy farms: between farming systems (organic vs. conventional) and among farms within farming systems. At the level of farming systems, we detected no differences in dung beetle species richness, abundance or diversity. The total biomass of beetles was slightly higher on conventional farms than on organic ones, but this difference did not correspond to a difference in dung-system functioning. However, at the farm level, we found significant differences in species richness, abundance and total biomass, reflected in significantly different provisioning of ecological functions among farms. Our results identify the importance of farm-specific variation in dung beetle assemblages for ecosystem functioning. Local decisions made by farmers may thereby override general differences among farming systems. Thus, policies aimed at promoting fine-scale management actions are an important supplement to general rules for certification under different farming systems. The current results are likely context-dependent, as based on efficient uptake and substantial environmental awareness among Swedish dairy farmers.