Br. Coppedge et Jh. Shaw, EFFECTS OF HORNING AND RUBBING BEHAVIOR BY BISON (BISON-BISON) ON WOODY VEGETATION IN A TALLGRASS PRAIRIE LANDSCAPE, The American midland naturalist, 138(1), 1997, pp. 189-196
Horning and rubbing behaviors of American bison (Bison bison) and thei
r effects on woody vegetation were investigated for 2 yr on a herd of
300+ animals reintroduced to a 1973-ha tallgrass prairie site in Oklah
oma. Horning and rubbing activity was significantly higher in summer t
han in other seasons. Whether this increase was associated with rut, s
hedding of winter pelage, insect harassment, or a combination of these
factors was unclear; however, these behaviors did have measurable imp
acts on the woody vegetation of the area. Bison injury to trees was mi
nimal, although one willow (Salix nigra) was uprooted and killed durin
g the Study, and several other trees were seriously damaged. Bison hor
ning had the greatest effect on saplings and shrubs, killing or severe
ly damaging 4% of the woody plants documented within the study area an
d causing moderate injury to 13% and light injury to 12%. Bison showed
a strong preference for small willows, killing or severely damaging 1
7% of the saplings and shrubs of this species during the study. Bison
also used artificial, man-made objects present on the landscape such a
s utility poles and fenceposts. Results suggest that horning and rubbi
ng by bison, along with fire and drought, may have influenced the hist
orical distribution of woody vegetation in prairie environments.