Effects of bison, cattle, and environmental factors on grassland dung beetle abundance and community structure
Trible, Morgan L.
AdvisorJameson, Mary Liz
MetadataShow full item record
Dung beetles are crucial ecosystem providers in grassland ecosystems, and research suggests that diverse dung beetle communities are required for improved ecosystem functioning. However, the factors driving dung beetle community structure are poorly understood. We compared the dung beetle community structure associated with bison-grazed and cattle-grazed temperate grasslands in Barber County, Kansas, USA. Our pilot study is the first to examine dung beetle communities (guild and species composition) associated with bison-grazed and cattle-grazed sites. We deployed dung-baited pitfall traps to examine dung beetle community structure associated with grazing site (cattle versus bison) and environmental factors (above-ground plant biomass, bare ground, and bulk density) that may affect dung beetle community structure. Our sample design included two sites (a bison grazed ranch and cattle grazed ranch), sampled with 4 transects comprised of 3 sample points for each grazing site (8 total transects; 24 total sample points). Soil textural class and percent sand in the soil were examined as covariates of the grazing site. We did not find a significant difference in total dung beetle abundance between the bison-grazed and cattle-grazed sites. But, two-sample t-tests, linear regression, PerMANOVA, and NMDS ordination showed that dung beetle communities differed on bison-grazed and cattle-grazed sites. These community differences are driven by above-ground plant biomass and bare ground, factors that are likely influenced by differences in bison and cattle grazing behavior. Additionally, we found that dung beetle communities are driven by percent sand in the soil – a factor that is not affected by the differing behaviors of bison and cattle. We hope our findings stimulate future research into the ecology of ecosystem services and inspire natural resource management centered around the conservation of diverse dung beetle communities.
Thesis (M.S.)-- Wichita State University, College of Liberal Arts and Sciences, Dept. of Biological Sciences