Diets of Ungulates Using Winter Ranges in Northcentral Montana

Abstract

Dietary comparisons based on fecal analysis of mule deer, elk, bighorn sheep, and cattle using mule deer winter ranges along the east slope of the Rocky Mountains indicated that elk, bighorn, and cattle diets were much more similar to each other than to mule deer diets. The greatest overlap between elk, bighorns, and mule deer occurred during late winter when creeping juniper became an important dietary item for all 3 species. Rank-order comparisons indicate that rankings of items in the graminoid and forb forage classes for diets of the 4 ungulate species were significantly correlated with availability of these items. Correlations between availability and diet rank-order were poor for items in the woody forage class. Differences in the diets of the 4 ungulate species were more pronounced at the forage class level than at the plant species/genus level.