Diversity and body size of dung beetles attracted to different dung types along a tropical land-use gradient in Sulawesi, Indonesia

Abstract

Abstract:Dung beetles are a functionally important component of most terrestrial ecosystems, but communities change with habitat disturbance and deforestation. In this study, we tested if dung beetle ensembles on dung of introduced cattle and of the endemic anoa, a small buffalo, are affected differentially by habitat disturbance. Therefore, we exposed 10 pitfall traps, five baited with anoa and five baited with cattle dung, per site in six habitat types ranging from natural and selectively logged rain forest to three types of agroforestry system (characterized by different management intensity) and open areas (n = 4 replicate sites per habitat type) at the margin of Lore Lindu National Park, Central Sulawesi, Indonesia. We found 28 species, 43% of which were endemic to Sulawesi. Species richness, abundance and biomass declined from natural forest towards open area. Large-bodied species appeared to be more sensitive to habitat disturbance and the ratio of large to small-sized dung beetles declined with land-use intensity. Although selectively logged forest and cocoa agroforestry systems had lower species richness compared with natural forest, they appeared to maintain a high portion of species originally inhabiting forest sites. The similarity of dung beetle ensembles recorded at forest and agroforestry sites reflects the high similarity of some habitat variables (e.g. vegetation structure and microclimate) between both habitat types compared with open areas. Species richness and abundances as well as species composition, which was characterized by decreases in mean body size, changed with land-use intensity, indicating that dung type is less important than habitat type for determining ensemble structure of these Indonesian dung beetles.

Aquatic insects indicate terrestrial habitat degradation: changes in taxonomical structure and functional diversity of dragonflies in tropical rainforest of East Kalimantan

“…However, overall species richness may not change at the local scale or can be even higher with growing intensity of disturbance (Hamer et al 1997;Shahabuddin et al 2010). Human-induced disturbances in the rain forest therefore result in pronounced changes in species composition and an overall reduction in species diversity.…”

Biodiversity patterns and trophic interactions in human-dominated tropical landscapes in Sulawesi (Indonesia): plants, arthropods and vertebrates

“…In an experimental field study (Shahabuddin et al 2008), we found that dung decomposition, in which dung beetles play a key role, significantly declined from natural forest to open cultivated areas. The decline was most likely related to the decrease of the functional group of large-bodied tunnelers from forest to open cultivated area (Shahabuddin et al 2008).…”

“…The decline was most likely related to the decrease of the functional group of large-bodied tunnelers from forest to open cultivated area (Shahabuddin et al 2008). This indicates that the ecosystem function provided by dung beetles was dependent on species identities and the functional groups involved.…”

“…In contrast to many other taxa, dung beetles have been identified as one of the most cost-effective group for biodiversity surveys in tropical forests , see also Kessler et al 2009). In addition they have proven to be very suitable to assess effects of disturbances on tropical ecosystems (Nichols et al 2007, Shahabuddin et al 2008, for example because they are abundant, vary highly with respect to species traits, and respond rapidly to environmental change (Slade et al 2007, Shahabuddin et al 2008). Another advantage is that relatively complete species inventories and data on the abundance of individual species can be achieved rapidly with standardized methods (Larsen and Forsyth 2005).…”

“…Dung beetle specimens were collected using pitfall traps baited with cattle dung (Bos taurus) as described in Shahabuddin (2008b) Studies on the potential contribution of agroforestry systems to the maintenance of tropical forest dung beetles in Central Sulawesi (e.g. Shahabuddin et al 2005Shahabuddin et al , 2007Shahabuddin et al , 2008 revealed that species richness and abundance decreased from natural forest to agroforestry systems and annual cultures (Figure 7) and species composition between those three land-use types were significantly different. (ANOSIM; global R = 0.85, p < 0.001, see also fig.…”