COMPETITION IN SYMPATRIC WHITE-TAILED DEER AND CATTLE POPULATIONS IN SOUTHERN PINE FORESTS OF OKLAHOMA AND ARKANSAS, USA

Inferences on competitive interactions between white-tailed deer Odoco ileus virginianus (Zimmermann, 1780) and cattle were made using inform ation on diet composition and quality. We hypothesized that dietary ov erlap between deer and cattle would increase with cattle density and t hat quality of deer diets would be higher in areas not exposed to catt le than in areas that were stocked with moderate to high cattle densit ies. Three treatments were delineated in McCurtain County, Oklahoma (h eavy cattle stocking), and Howard (moderate to light cattle stocking) and Pike (no cattle stocking) counties, Arkansas. Treatments were simi lar with respect to soils and vegetation but differed with respect to cattle stocking rate tie number of cattle/ha). Deer and cattle diets a nd concentrations of fecal nitrogen (FN) (an index to dietary quality) were determined from feces that were obtained from 12 randomly select ed collection areas (4/treatment) from October 1986 to October 1988. D ietary overlap of deer and cattle was highest in winter and lowest in summer. Dietary overlap of deer populations was lowest for populations exposed to heavy cattle stocking and no cattle stocking, which sugges ted that competition between the deer and cattle occurred in winter. F ecal nitrogen was lowest in deer feces collected from treatments with cattle stocking in February but higher in August and October. Both die tary quality and dietary overlap suggested possible competitive intera ctions between deer and cattle in winter. However, higher dietary forb and dietary quality for deer in summer exposed to cattle suggested th at cattle can facilitate growth of early successional plant species in pine habitats.