New import for Australia
Meet the beetle: Onthophagus vacca
Dung beetle activity is high in many parts of Australia, however there are some locations where dung beetles are not as numerous or active at certain times of year. Interestingly, there are reported European and African locations where dung beetles are active all year round and the climate is similar to southern Australia.
New species for introduction into Australia are selected based on their efficiency at burying dung, seasonal activity and distribution in their native range. Onthophagus vacca (pictured) is a northern hemisphere spring-active dung beetle that was first introduced to Australia in the 1980s, but failed to establish. Due to its high potential, it was introduced again in 2014. O. vacca is native to the southern and south-central Europe and northern Africa, an area with climate very similar to regions in southern Australia. These beetles reproduced in the field and have now been introduced to a number of locations in WA, SA, Vic and NSW .
The new strain of O. vacca is expected to survive and reproduce better in Australia than earlier introductions.
Onthophagus vacca is a medium-sized beetle. Males have one central horn that varies in size depending if they are major or minor males, while females have two shorter horns. Colouration may vary between individuals (see photo). O. vacca is attracted to cattle and sheep dung in open pasture and is active in spring and early summer. When emerging from winter, adults feed for several weeks before breeding. O. vacca is a tunnelling species and excavates brood chambers under dung pads. While females dig the tunnels, the males help move dung towards the entrance. Females lay eggs for three to four months. Larvae develop in the brood chambers. Adults enter diapause over the winter period and emerge in the following spring. These dung beetles produced about 30 eggs per female at CSIRO laboratories; in the field they produce one new generation per year.