Dung beetle communities and impact on dung degradation and horn fly population under different management practices

Dung beetles (Coleoptera: Scarabaeidae) are vital contributors to waste recycling in grazed ecosystems, particularly those involving large vertebrates such as cattle and bison. This study evaluated the diversity and abundance of dung beetle communities across various grazing systems in Oklahoma, with a focus on comparing cattle management to bison-grazed landscapes. Monthly samples with baited pitfall traps were collected from May to August 2024 across multiple sites, including organically managed ranches, conventional grazing systems, and the bison-grazed Tallgrass Prairie Preserve. A total of 42,049 dung beetles were collected comprising eleven species or species groups. Significant differences in community composition and abundance existed by month and grazing systems. Species diversity peaked in the spring and declined towards late summer, particularly in conventionally managed grazing systems. In systems with more dung beetles, dung decomposition was faster with 80% degradation in a 16-day period. During periods of peak dung beetle activity horn fly, Haematobia irritans, numbers were also lower despite organic management. These findings underscore the positive impact of organic and rotational grazing practices, which support higher dung beetle diversity compared to conventional systems. Furthermore, this research highlights the essential role of dung beetles in nutrient cycling and soil health, particularly in grazing landscapes that incorporate adaptive management practices. These results reinforce the ecological importance of dung beetles in maintaining pasture health, improving cattle production systems, and reducing the need for chemical fly control methods. By enhancing dung breakdown pest species such as horn flies that breed in manure can be reduced.