In Europe, where livestock farming has largely replaced wild ungulates over the centuries, dung beetle communities have become highly dependent on domestic herbivore farming practices. They could therefore constitute good indicators of the impact of reintroducing large herbivores into ecosystems.
In a study carried out on three dry grasslands in the Causse Méjean (southern France), researchers compared dung beetle communities and the rate at which dung disappeared in systems grazed by three types of herbivore: a population of Przewalski's horses managed by natural selection, a herd of sheep and a herd of endurance horses.
The results show significant differences in dung composition between herbivores, but an overall similar dung beetle community between sites. However, the structure of this community varies: burrowing dung beetles dominate everywhere, while rolling dung beetles are more abundant in domestic livestock systems, and sedentary dung beetles become more represented in Przewalski horse pastures.
These differences could explain why sheep droppings decompose more quickly than horse droppings. They also highlight the close link between the history of sheep pastoralism and the dynamics of dung beetle communities in European semi-natural grasslands.
This study, published in Journal of Environmental Management by Clémentine Mutillod, William Perrin, Élise Buisson, Laurent Tatin, François Mesléard, Pierre Jay-Robert et Thierry Dutoit, highlights the importance of dung beetles as ecological indicators of grazing systems.