Record Details
Use of range sites by pronghorns in south central Oregon
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Use of range sites by pronghorns in south central Oregon |
| Names |
Herrig, Daniel M.
(creator) Vohs, Paul A. (advisor) |
| Date Issued | 1974-05-01 (iso8601) |
| Note | Graduation date: 1974 |
| Abstract | Relative use by pronghorns (Antilocapra americana) of 16 range sites was studied during summer and fall of 1971 and 1972 on Hart Mountain National Antelope Refuge, an area of high desert rangeland in south central Oregon. A Relative Use Index was developed based upon 1533 observations of pronghorns located on belts of known area to evaluate preference of pronghorns for range sites and condition class. A wide range in moisture conditions during the 2 years of the study affected soil moisture, succulence of vegetation, and availability of drinking water. In 1971, a year of above-average rainfall, pronghorns preferred upland xeric range sites, specifically Rocky Terrace that was dominated by Artemisia arbuscula. Below average rainfall occurred in 1972 and lowland mesic sites with succulent vegetation and water sources nearby were preferred by pronghorns during that year. Ninety-five percent of all observations in 1972 were within 3200 meters of water. Juxtaposition of other sites appeared to be important in influencing use of specific range sites by pronghorns. Range sites with vegetation above 75 cm in height and/or steep topography were not used as much as other sites by pronghorns. Average size of pronghorn groups increased from 4.2 in 1971 to 6.0 in 1972 when pronghorns concentrated on small lowland range sites near water. There was no apparent differential use of range sites by groups composed of different age and sex classes of pronghorns. A broad band of rough terrain and arid flat desert apparently acted as a natural barrier separating two populations of pronghorns on the refuge. |
| Genre | Thesis/Dissertation |
| Topic | Range management -- Oregon |
| Identifier | http://hdl.handle.net/1957/22367 |
