Kie et al. found that cattle (Bos taurus) grazing on California summer range reduced available herbaceous forage for mule deer (Odocoileus hemionus). In response to cattle grazing, the mule deer decreased the length of their resting time and increased time spent feeding each day. Deer spent the least amount of time feeding in ungrazed areas, more time feeding in moderately grazed areas, and the majority of time feeding in heavily grazed areas. The size of mule deer home range was positively correlated with the increased stocking rate. These larger home ranges, usually including steeper slopes, increased mule deer energy demands. Cattle grazing decreased fawn hiding cover, which may have led to increased fawn mortality by predation. Kie et al. believe that the increase in day time foraging hours by mule deer decreased the amount of time available for resting and looking for predators. Overall, this study found that competition between cattle and mule deer exists on the summer range, especially with higher cattle stocking rates and below-average precipitation.
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.