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Dung beetles (Scarabaeidae) are common detritivores, and especially the tunnelling genera Geotrupes, Anoplotrupes and Onthophagus enhance the soil quality and support nutrient cycles by rapid burial of mammalian dung. These functionally important beetles are faced with a wide range of anthropogenic disturbances and changes in environmental conditions due to land use. We thus conducted quantitative surveys of the abundance (converted to total biomass) of dung beetles and their dung removal rates (g per two days) in 150 forest and 150 grassland sites with varying land-use intensity, located in north-east, central and south-west Germany. We used dung from livestock (cow, sheep, horse) and game animals (wild boar, red deer and fox) to provide a characteristic spectrum of dung resources on each site. Most dung beetle species showed habitat preferences: Anoplotrupes, Typhaeus and several Aphodius species almost exclusively occurred in forests, while most Onthophagus individuals were found in grasslands. In total we collected 18780 individuals from 33 species. The average dung beetle biomass was 36 times higher in forests than in grasslands, and their effective dung removal rate was 3 times increased. The beetles’ total biomass was strongly correlated to their removal rates. In forests, the amount of wood harvesting significantly reduced dung removal rates by 20%, and mowing frequency (−7%) and fertilisation (−4%) had a significant negative effect in grasslands. Dung removal by beetles increased with grazing intensity (+6%), however, and was higher in non-native coniferous forests (+22%). Overall, our study demonstrates negative effects of habitat conversion from forest to grassland, and negative effects of land-use intensity within forests and grasslands on dung beetle activities.

Ancient woodlands differ from recent woodlands by numerous abiotic and biotic factors, including soil properties. Several animal species are more abundant in ancient than in recent woodlands, but this has been only rarely tested for saprophagous taxa and not at all for dung beetles, which are common in temperate woodlands. Beside habitat continuity, tree age can have also an effect on woodland inhabiting animals, especially on saprophagous taxa. To analyze the effects of both habitat continuity and tree age we studied dung beetles in a continuous north-west German woodland with baited pitfall traps on basis of a factorial design. We compared species diversity (Shannon-Wiener-Index and Pielou's Evenness), catching rates, biomass and community composition of dung beetles. With only 18 recorded species from 20 study plots, dung beetle communities were species-poor and dominated by one large tunnelling species. The main result is that catching rate and biomass of dung beetles were higher in ancient woodlands, which was due to the particularly high catching rate of the most dominant tunnelling species and one dweller species. Tree age alone had a minor impact, but affects significantly one rare species. Diverging habitat quality of ancient and recent woodlands likely explains differences in the communities of dung beetles in woodlands of different habitat continuity. Old trees in recent woodlands could not compensate for habitat continuity of ancient woodlands.