Deer and Cattle Diets on Summer Range in British Columbia

Abstract

A study was made on the forage selection of mule deer and cattle on summer range in the Douglasfir zone. Both ungulates showed a high preference for clover, willow, and fireweed. When the availability of these forages was not limiting, the percent of diet overlap was high. As their availability declined, diet overlap decreased as both deer and cattle were forced into their individual food niche. For cattle the niche was grass, while for deer it was shrubs. The effect of declining availability of preferred forages on the dietary composition was less for deer than for cattle. Presumably the greater ability of deer to be selective permitted them to utilize those forages despite reduced availability.