Cementing its place in popular science as well as the bush, the iconic dung rolling beetle is famous for its unusual nesting methods. With two species already established in Australia, a third could soon be rolling its way to inland regions, bringing numerous land and livestock benefits to willing recipients.
Of all the dung beetles, dung rollers are the most popular and well known. These fascinating beetles have the curious habit of shaping mounds of dung into perfectly round balls and then rolling them across the ground to a favourable site for rearing their young. When they find a suitable site, they dig a shallow hole for the ball or attach it to vegetation and the female lays an egg in it. From this point, their biology is similar to that of other dung beetles; the larvae feed on the dung ball from the inside out, and when they complete development, they pupate within the dung ball and wait for the right moment to chew their way out as an adult beetle, ready to repeat this unusual life cycle.
Dung rollers, known technically as telecoprids because they rear their young at a distance from a dung pad (‘tele’ meaning ‘at a distance’), are commonly found in many arid areas of the Mediterranean region and Africa. Two dung-rolling species have become established in Australia: Sisyphus spinipes (found mainly in Queensland) and Sisyphus rubrus (found in Queensland and northeastern New South Wales). Although dung rollers do not have as great an impact on nutrient and water penetration into pasture soils because of their shallow tunnels, they are nonetheless able to rapidly dispose of dung pads, often in a matter of hours. Thus, they add a useful dimension to the array of previously introduced dung beetles in Australia.
A third dung roller is slated for importation into Australia in the near future. Once bureaucratic hurdles are surmounted, Gymnopleurus sturmi will be brought into quarantine facilities managed by CSIRO. The strains of G. sturmi to be imported are from northern Africa and are notably drought tolerant. Following successful rearing, this species will become a welcome complement to the introduced dung beetles managing dung in inland Australia.
