Associations of scarab beetles (Insecta: Coleoptera: Scarabaeidae) with dung of four species of mammals in Khao Yai National Park, Thailand

To determine if dung from various species of native mammals are attractive to species of Scarabaeidae differentially in a seasonal evergreen forest in Thailand, we used pitfall traps baited with fresh dung of four species (barking deer, sambar deer, Asian elephant, pig-tailed macaque) and an unbaited control. The pitfalls were deployed in Khao Yai National Park for 24 hours in March 2010. All totaled, 9 genera and 23 species of scarab beetles were collected. Of these, Loboparius schereri (Petrovitz) represents a new country record with a known range to the northwest of Thailand. Overall scarab abundance and richness each differed significantly (p< 0.001) among bait types. From a multivariate perspective, discriminant function analysis computed four axes to distinguish the community of scarab beetles that was attracted to each dung type. The pigtailed macaque dung community was significantly different from that of all other baits (p< 0.001), whereas overlap existed among the other bait treatments; 83.3% of the pitfalls were re-classified to the correct bait type. Dung of the omnivorous macaques attracted a beetle community that was dramatically distinct from those of the other bait treatments and with the greatest abundance and richness of scarab species, whereas dung of the herbivorous species was far less attractive. This corroborates New World studies that have shown dung from the diet of omnivorous mammals attracts greater numbers and diversity of dung beetles. As such, conservation of omnivorous large animals in tropical forest systems is necessary for the conservation of rich dung beetle communities.