Bison (Bison bison) chose to graze grass-dominated patches and avoided shrub and forb-dominated patches, while cattle (Bos taurus) chose patches with high-quality forbs and browse. Throughout the entire summer, cattle devoted more time to grazing than bison. During the rut, bison primarily consumed graminoids to balance nutrient and time constraints. The connection between social time investment and forage patchiness is an essential part to clarifying diet choice differences between bison and cattle. Browse forage and forbs were equally digestible by both species. In vitro dry matter digestibility (IVDMD) of cool season and warm season grasses was greater for bison than cattle. Crude protein IVDMD was similar for both species. Through different foraging behavior, cattle and bison obtain similar levels of dietary quality.
Citations and enhanced abstracts for journals articles and documents focused on rangeland ecology and management. RSIS is a collaboration between Montana State University, University of Idaho, and University of Wyoming.