DIET QUALITY AND INTAKE REQUIREMENTS OF ADULT FEMALE CARIBOU OF THE DENALI HERD, ALASKA

This paper incorporates empirical, derived, and theoretical values of diet digestibility, dry matter intake requirements (DMI), diet nutrient content, and N and P balance in a summary of the nutrient regime of well-nourished adult female Rangifer tarandus granti. Derived DMI requirements were 86, 104, 104 and 74 g kg-0.75 day-1 during spring, summer, autumn and winter, respectively. Values predict that caribou consuming a lichen-dominated diet are in a negative P balance and probably a negative N balance. Pregnancy and survival rates indicate caribou are well adapted to this winter diet. Dietary Ca, K and Mg are likely to be adequate all year round. Caribou of the Denali herd frequented mineral licks in spring and summer, probably to supplement Na-deficient forage. -from Author