The changing diversity and ecosystem function of dung beetles on the Canadian prairies: A never-ending story

The fresh dung of large ruminants provides a moist and rich habitat for hundreds of insect species.  Dung beetles (Scarabaeidae) are chief among these, dominating in terms of abundance, biomass and ecosystem function.  Dwellers (mainly species of Aphodiinae) develop from egg-to-adult within the pat.  Fragmentation of the pat occurs over a period of weeks via the feeding activity of the larvae.  In contrast, rollers and tunnelers (species of Scarabaeinae and Geotrupidae) can bury or disperse fresh dung pats in hours or days.  Adults arrive at fresh pats and remove portions of dung that they bury at some distance from (rollers) or below (tunnelers) the pat.  The buried dung provides food for larvae that hatch from eggs laid in the dung at the time of burial.  In addition to more rapidly removing the pat from the soil surface, tunnelers and rollers relocate nitrogen (in the form of dung) directly into the root zone of growing plants and, through their tunneling activities, improve the permeability of the soil to water and air.  The current presentation will examine how the assemblage and ecosystem function of dung beetle species has changed on the Canadian prairie since the demise of the American bison and how these changes continue through to the present day.