Biology and ecology of Circellium bacchus (Fabricius 1781) (Coleoptera, Scarabaeidae), a South African dung beetle of conservation concern

The dung beetle Circellium bacchus (Fabricius 1781) was once widespread in southern Abica but is now restricted to a few isolated fragments in the south of the Western and Eastern Cape Provinces of South Africa, with the largest population present in the Addo Elephant National Park (AENP). The beetles' activity is governed by precipitation and temperature; 18-26 "C and high relative humidity favour activity. The beetles are generalist dung feeders and breeders but have clear preferences for elephant dung for feeding, and buffalo dung for breeding. Fecundity is the lowest recorded for a dung beetle, with a maximum of two but on average only one progeny produced per year. The species is unique amongst ball-rolling (telecoprid) dung beetles in that females initiate, form and roll brood balls, something carried out exclusively by males in other species. The beetles are habitat specialists preferring dense undisturbed vegetation to more open, disturbed vegetation. The species should be considered rare because of its narrow geographical range, restricted biotope specificity and biological attributes. Furthermore, it complies with most of the characteristics that increase its likelihood of endangerment or extinction and qualifies as "vulnerable" according to IUCN criteria of threatened species.