Foods of Elk and Other Ungulates at Low Elevations in Northwestern Colorado

Abstract

In northwestern Colorado on areas where elk (Cervus canadenzis) and wild horses have been increasing in recent years, the diets of elk, cattle and wild horses consisted mainly of sedges and grasses. On the same areas mule deer (Odocoileus hemionus) have been decreasing steadily recently, and their diets were mostly browse. The foods of elk, wild horses, and cattle were much more similar to each other than any one of the herbivore diets was to that of mule deer. Cattle and wild horses have strikingly similar diets, and if forage was limited they would compete strongly for forage. There appears to be no large herbivore on the study areas that competes significantly for foods with mule deer. J. WILDL. MANAGE. 41(1):76-80 During the past 30 years elk in Colorado have been increasing slowly. During the past 15 years mule deer have declined rapidly. Record high numbers (23,946) of elk and near record low (46,666) deer numbers were harvested in 1974 (Riffel 1975:1). According to the most recent summary for 1975, the deer harvest was 14 percent less in 1975 than in 1974 (Lashnits 1975:1). In some low elevational ranges in northwestern Colorado, nonmigratory herds of elk have become established where they are not legally hunted or where only a few hunting permits are issued. Some of these same ranges also have increasing herds of wild horses (Cook 1975). There is growing concern for multiple use management of rangelands, and information pertaining to foods shared among different herbivores using a particular range is relatively limited. When provided protection from predators and man, large herbivores not only tolerate but may thrive within broad limits of climate, soil, topography, and vegetation. The food habits of large herbivores are generalized. Precise predictions of the botanical composition of diets of a species of herbivore may differ significantly between areas occurring wit in the same vegetation type. The purpose of this study was to determine the botanical composition of the diets of elk, mule de , wild horses, and cattle on the same