Dung beetles provide the important ecosystem service of collecting dung from mammals and burying it. The dung is food for their offspring that grow and develop on what the parents provide. Burying prevents other insects such as flies from breeding in the dung. The dung beetle larva is spared the competition and humans are spared large populations of biting flies that would otherwise breed on the dung.
Numerous parasites are transmitted in dung and efforts to protect human and animal health have led the use of Ivermectin, an anti-parasite drug fed to livestock. However, the Ivermectin is excreted into the dung where it can have an adverse effect on dung beetles. Several regions of the world have experienced declines in dung beetle populations. Some suspect that Ivermectin use may bear some responsibility.
Verdú & Colleagues* found that Ivermectin, in concentrations lower than those typically present in dung, interfered with olfactory sensing and locomotion in adult Scarabaeus cicatricosus dung beetles. The study did not address the effect of Ivermectin on dung beetle larvae or overall ecosystem services. However, a reduction in dung beetles and their ecosystem services would require a reevaluation of Ivermectin use to better manage both parasites and dung beetles.
José R. Verdú & Colleagues. 2015. Low doses of ivermectin cause sensory and locomotor disorders in dung beetles. Nature Scientific Reports 5:13912