The role of local and regional processes in shaping dung beetle communities in tropical forest plantations in Borneo

We examine whether rain forest dung beetle species found in plantations in Sabah, northern Borneo, tend to be endemic or geographically widespread. In addition, linear regressions of abundance vs. distance from a major river in primary rain forest are calculated to see if species found in plantation forest show affinity to one specific biotope (riverine vs. interior forest) in their natural habitat. Results show that 14 of the 40 species recorded from plantations are endemic to Borneo. Only edge-specialist endemic species are found in plantation forest, with no interior-forest specialists recorded. Data suggest that endemic species that are adapted to more exposed conditions in primary rain forest, such as riverine species, can in some instances tolerate man-made habitats. Twenty-nine species (±SE 4.0) per transect are recorded from plantation transects, whereas 44.2 (±1.7 SE) are recorded in primary rain forest. As species richness is much lower in plantations than natural forest, implying loss of biodiversity, we conclude that measures of biogeographic distinctiveness, whereby endemic species confer higher values, may be misleading unless they take into account edge-affinity. Local- as well as regional-distributional data may therefore be needed to interpret correctly patterns of species assemblages in derived forest ecosystems.