Landscape occupancy by free ranging cattle in northeast Oregon

Graduation date: 2011Global Positioning System (GPS) and Geographic Information System (GIS) technologies were employed to evaluate cattle occupancy of three landscape attributes on three different grazing allotments administered by the Wallowa Whitman National Forest in Northeast Oregon. Topographic characteristics of slope; 0-4%, 4-12%, 12-35% and >35% were evaluated as well as north and south aspects. Vegetation alliance categories of ponderosa/Douglas fir (pine/fir), mixed conifer and upland grass were also assessed. Occupancy of area around perennial streams was analyzed using buffer zones of 0-10m (aquatic habitat), 10-20m, 20-30m, 30-40m, 40-50m and 50-60 meters from both sides of the watercourse. As well an appraisal of total cattle landscape occupancy for each allotment (study site) was performed by individual sample animals and by sample sets as an evaluation of the home range concept as applied to managed domestic cattle.\ud Cattle preferred slopes less than 12% did not avoid slopes between 12 and 35% but did avoid slopes greater than 35%. Cattle were indifferent to north and south aspects.\ud Vegetative alliance structures were variable as to preference by cattle. In study area 1 mixed conifer was avoided while the pine/fir and upland grass were both equally preferred. Cattle in study area 2 preferred only the mixed conifer while avoiding both the pine/fir and upland grass classifications. Study site 3 cattle also preferred mixed conifer and displayed moderate avoidance toward upland grass and pine/fir.\ud When occupancy of cattle was evaluated for the buffer zones designated on either side of perennial streams, cattle in site 1 and 3 were indifferent to all zones demonstrating equal dispersion throughout the area evaluated. As well the individual zones in these study areas were occupied less than 1%. In site 2 cattle preferred the first three zones out to 30m over the area between 30 and 60m. In all study sites cattle occupied the allotment area beyond 60m between 96 and 98 percent of the time while the aquatic habitat zone (0-10m) was occupied less than 1% in all study areas.\ud Landscape occupancy was shown to be variable between allotments. Individual animal average for site 1 was 40 to 50% less per year than the average in study area 2. Variation between animals was also less in area 1 as compared to area 2. Site 3 was evaluated for one year's data and with a time period over twice that of site 1 and 2 so comparisons between this site and the others are merely illustrative. The average of individual samples was larger than both area 1 and 2 but with less variation than all trials except site 1 during the 2008 trial