title: Linking functional group richness and ecosystem functions of dung beetles: an experimental quantification.
abstract: Dung beetles form an insect group that fulfils important functions in terrestrial ecosystems throughout the world. These include nutrient cycling through dung removal, soil bioturbation, plant growth, secondary seed dispersal and parasite control. We conducted field experiments at two sites in the northern hemisphere temperate region in which dung removal and secondary seed dispersal were assessed. Dung beetles were classified in three functional groups, depending on their size and dung manipulation method: dwellers, large and small tunnelers. Other soil inhabiting fauna were included as a fourth functional group. Dung removal and seed dispersal by each individual functional group and combinations thereof were estimated in exclusion experiments using different dung types. Dwellers were the most diverse and abundant group, but tunnelers were dominant in terms of biomass. All dung beetle functional groups had a clear preference for fresh dung. The ecosystem services in dung removal and secondary seed dispersal provided by dung beetles were significant and differed between functional groups. Although in absolute numbers more dwellers were found, large tunnelers were disproportionally important for dung burial and seed removal. In the absence of dung beetles, other soil inhabiting fauna, such as earthworms, partly took over the dung decomposing role of dung beetles while most dung was processed when all native functional groups were present. Our results, therefore, emphasize the need to conserve functionally complete dung ecosystems to maintain full ecosystem functioning.
authors.affiliation: Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, Belgium. tanja.milotic@ugent.be.
authors.forename: Tanja
authors.identifier: http://orcid.org/0000-0002-3129-6196
authors.initials: T
authors.lastname: Milotić
authors.affiliation: Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, Belgium.
authors.forename: Stijn
authors.initials: S
authors.lastname: Quidé
authors.affiliation: Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Van Loo
authors.affiliation: Terrestrial Ecology Unit, Department of Biology, Ghent University, Ghent, Belgium.|Research Institute for Nature and Forest, Brussels, Belgium.
authors.forename: Maurice
authors.initials: M
authors.lastname: Hoffmann
mesh_terms: D000818:Animals; D001517:Coleoptera; D017753:Ecosystem; D005243:Feces; D058614:Seed Dispersal; D012987:Soil
chemical_list: D012987:Soil
keywords: Dung beetles; Dung removal; Functional groups; Secondary seed dispersal