Diversity and abundance of dung beetles in Pakwach Sub-county.

Abstract

Dungbeetles are key-stone species in ecosystems playingimmenseecological roles and are thus bio-indicators for habitat quality and environmental modifications in the tropics.Documentation of the distribution, diversityand abundance of dung beetles is a primary step towards their conservation. However, for Uganda, this documentation is still lagging behind immensely. This study was conducted to assess the diversity and abundance of dung beetles in different habitats of Pakwach sub-county, Pakwach district. Field sampling was conducted in December2019and January2020.Twomethods were usedi.e. directsearch along established transectsand pit fall traps in the different areas. Samplescollected were cleaned and stored in vials containing 70% ethanol. Laboratory identification was done at Makerere University withthe aid of standard guidesand online resources.A total of 3,277 dung beetles were collected comprisingten genera and nineteen species with Proagaderus sp 1(70.5%)being the most abundant and Proagaderus sp 3(0.1%)the least abundant.Mean dung beetleabundance was not statistically significant between the two parishes (F =1.853, df = 1, p>0.05)though there were more individuals recorded in Mukale than in Paroketo.The numbers of individuals sampledusing pitfall traps were significantly higher than those recorded fromdirect search (F = 11.943, df =1, p< 0.001), but some species were only recorded from the direct search. Similarly, cattle dung registered significantly more individuals compared to the goat and human dung (F =4.787, df= 2, p<0.001). Although there were more tunnellers compared to dwellers and rollers, the numbers were not statistically different (F = 1.850, df = 2, p> 0.05). However, removal of the most abundant tunneller significantly shiftedthe interaction to dwellers. Therewas differential variation in theinfluence of environmental variables on dung beetle abundance in Pakwach sub-county;somevariables showed positive effects on the dung beetles while others showed a negative impact. For a better dung beetle survey, a combinationof sample methods should be used i.e. both direct search and pitfall traps. Additional studiesencompassing climate change aspects, parasite suppression mechanisms, phylogenetic relationships and threats todung beetle communitieswill be needed to provide moreinsight on these least studied ecosystem engineers.