Foraging rates of wapiti on alfalfa/bromegrass pastures

Abstract

Within Aspen–Boreal ecosystems, little information exists on functional response of wapiti foraging on improved pastures. We compared feeding rates (g/min) of wapiti ( Cervus elaphus nelsoni) on predominant bromegrass ( Bromus riparius Rhem. cv. Regar) and pure alfalfa ( Medicago sativa L.) pastures as they were progressively defoliated. In grass-dominated stands, estimated dry matter (DM) and energy intake rates of wapiti were asymptotically related to available herbage, and superior to pure stands of alfalfa at herbage levels below 2500 kg DM/ha. On pure alfalfa stands, crude protein (CP) intake rates exceeded those on grass-dominated stands when herbage biomass exceeded 1700 kg DM/ha. Intakes of CP (0.5–2 g/min) were similar below this biomass. A third order polynomial described the forage intake for wapiti in response to the complex structure of alfalfa dominated pastures. The study provides guidelines in terms of forage mixtures and grazing systems for the wapiti industry. Feeding standards are needed as the high costs of containment of wapiti have led to rather intensive pasture use.