Variation in coprophagous beetle (Coleoptera: Scarabaeidae and Hybosoridae) abundance and richness after the 2019/20 megafires at Mt. Kaputar National Park and Pilliga Nature Reserve in New South Wales, Australia

Abstract

This study examines the impact of fire on the assemblages of coprophagous beetles at two woodland locations: Mt. Kaputar National Park and Pilliga Nature Reserve in New South Wales, Australia. At each location, sites burnt by wildfire in 2019/2020 were classified by severity level (low, medium, and high) and sampled systematically, with unburnt sites used as a control. Beetle abundance and richness were recorded for each site and severity level. Statistical analyses demonstrated significant variations in beetle abundance across fire severities at both locations, with distinct species-specific responses to fire severity. Species like Onthophagus squalidus and Liparochrus sp. at Mt. Kaputar were found in higher abundance within unburnt, low severity, and medium severity areas. At Pilliga, species like Onthophagus consentaneus and Onthophagus dandalu were found in higher abundance within unburnt or low severity areas and Onthophagus taurus and Onthophagus tenebrosus were found in higher abundance within high severity areas. It was found that increased fire frequency led to reduced beetle abundance at both locations, wildfire frequency also had a negative effect on beetle abundance. However, prescribed fires had no effect on beetle abundance. As fire frequency increases, it will likely lead to lower beetle abundance and increase the risk of beetle extinction.