Dung beetle assemblages on reclaimed coal mines in eMalahleni (South Africa) their environmental associations and tunnelling ability on compacted soils

Opencast coal mining operations are a major contributor to habitat destruction through the removal of soil, vegetation and fauna from an area. Habitat loss and fragmentation is known to adversely impact invertebrates because of their small size and limited dispersal range that also applies to local dung beetle assemblages. Dung beetles have the potential to aid in reclamation efforts through their beneficial activities in soil although there is little known about their assemblages on reclaimed mine land. Additionally, highly compacted soils are a feature of reclaimed mine sites that may pose a significant challenge to tunnelling dung beetles and may limit their remediation benefits. This study aimed to describe the local dung beetle assemblage in terms of species richness and abundance on reclaimed mine sites in comparison to reference areas (including cattle farms and a protected area). Furthermore, it aimed to determine if dung beetles can tunnel into compacted soils, and how these soils may influence their tunnelling depth as shown through penetration resistance measurements. Dung beetles were collected using standard baited pitfall traps from five reclaimed mined sites and three reference sites (two cattle farms and a Telperion Nature Reserve) from January 2015 to April 2017. Various abiotic factors that could influence the distribution of beetles were measured including soil bulk density, vegetation cover, humidity and soil texture. Dung beetle abundance was found to be significantly higher at the Telperion Nature Reserve than any other site (F (7, 56) = 8.613, p