Effect of Forage Depletion on the Feeding Rate of Wapiti

Abstract

We evaluated forage intake rates of wapiti (Cervus elaphus nelsoni) during the depletion of a grass sward over a 7-day period. Bite sizes increased linearly with forage biomass and plant height within the range of our data. Maximum foraging rates of 45 cropping bites per minute declined exponentially at bite sizes greater than 0.2 g. Consumption rates increased asymptotically with forage biomass to a predicted asymptote of 17.6 g/min although the highest value observed was 12.6 g/min at a biomass of 2367 kg/ha. Average daily forage removals through grazing and trampling (not distinguished) were 9.5 kg per animal and did not decline as biomass was reduced from approximately 2,400 kg/ha to 800 kg/ha.