Utilisation of introduced Brazilian pastures ecosystems by native dung beetles: diversity patterns and resource use

1. Cattle pastures dominated by introduced grasses are a characteristic component of many tropical landscapes in Brazil, yet little information is available concerning the insect communities that inhabit these novel ecosystems.
2. Dung beetles are a conspicuous element of pasture insect communities, and make a significant contribution to dung decomposition, parasitic fly control, and soil bioturbation.
3. We sampled dung beetle assemblages in twelve introduced pastures near Viçosa, Minas Gerais, Brazil. We used pitfall traps baited separately with cow and horse dung, and collected a total of 456 dung beetles, comprising 23 species from 13 different genera. We analysed patterns of alpha and beta diversity, community structure, and species composition among pastures and bait types.
4. Cow dung harboured significantly more species, but a similar abundance of dung beetles compared with horse dung. However, both dung types supported species exclusive to that type, and hosted a distinct dung beetle community structure and composition.
5. Although livestock (cattle and horses) was introduced to Brazil less than 500 years ago, our data suggest that novel and well-structured dung beetle communities are actively exploiting these novel food resources in Brazilian pasturelands.