Although it varies with conditions and seasons, ideal elk habitat typically consists of mountainous terrain with alpine meadows and lush valleys. Elk also thrive in rolling foothills in many parts of the West. In general, elk need habitat that is 40 percent cover and 60 percent foraging areas. Elk prefer moderately steep, south-facing slopes during winter because of the warmer temperatures and reduced snow pack. Forest stands interspersed with grassy openings provide food, thermal cover, and travel lanes.
Components of Foraging Habitat
Consuming high-energy foods is the best way for elk to store reserves and minimize the need to deplete these reserves. In addition to high-quality feed, elk may choose to forage in areas that offer other benefits, such as south-facing slopes in winter, shade or a breeze to deter insects in the summer, seclusion, protection from wind, or a combination of factors.
Elk diets vary according to the season.
- Spring forage includes early-greening grasses and forbs that are highly palatable, succulent, and nutritionally rich. Elk need a low-fiber/high-protein diet composed largely of grasses, sedges, and early forbs. Green-up occurs first on south- and west-facing slopes, so elk tend to occupy these the most. Elk move to higher elevations following the growth of new, young forage to maximize their nutritional plane. In this way, they can best replenish body reserves and satisfy increased nutritional demands during gestation, lactation, and antler growth.
- During summer, elk diets are composed of 60 to 100 percent forbs if they are available. Preferred forbs include dandelion, geranium, asters, clovers, and milkvetches. As forbs dry in late summer, elk utilize more grasses and shrubs.
- Fall begins a period when herbaceous (leafy) vegetation contains reduced protein but is still a good source of energy. Grass averages 73 percent of the fall diet, and elk begin to use more shrubs.
- Grasses may make up as much as 84 percent of an elk's diet in winter. Elk do best on winter ranges with a mix of herbaceous vegetation and browse. When heavy snow is present, elk will often seek out herbaceous forage on south- and west-facing slopes and wind-swept ridge tops. These areas often have shallow, dry soils and, although production is limited, forage quality is usually better than on adjacent sites with deeper soils. These plants usually have more protein and are more palatable. Browse use increases during the winter. Choice browse species include quaking aspen, mountain maple, serviceberry, ceanothus, chokecherry, red-osier dogwood, mountain mahogany, willow, and winterfat. Choice grass species include rough and Idaho fescue, bluebunch and western wheatgrass, and Sandberg bluegrass. While browse is the primary winter food for elk west of the Continental Divide, grasses tend to be the primary winter food for elk in areas east of the divide.
Cover Habitat
Cover is important to elk for security or escape and for protection from extreme weather. Elk use security cover most during calving and periods of disturbance, such as hunting season. Once calves are old enough to move with the herd, elk spend more time in the open. In areas that have significant hunting pressure, elk spend more of their time in, or near, large blocks of escape cover away from roads.
Thermal cover is very important for elk. During summer, it provides shade; during winter, thermal cover reduces heat loss and wind velocities. A cover of dense conifers reduces heat loss, particularly on very cold nights with clear skies.
Habitat Management Suggestions
Management of rangelands for elk must consider dual and competitive uses of important forage species by domestic livestock. Use of a range is usually determined by examining the percent of annual growth of plants eaten by animals — domestic and wild. As a rule of thumb, we know that forage is being utilized too heavily when more than 50 percent of the available annual growth of key species has been consumed. In such cases, either livestock or elk numbers should be reduced — by seasonal management of livestock or by increased harvest of elk through hunting. To recognize proper use, overuse, and general range conditions, an experienced range conservationist, biologist, or soil conservationist can be helpful.
Woodland habitat in mountainous elk range usually accumulates deep snow in the late fall and winter, and elk must migrate into the foothills and lower rangelands for winter forage. This is a critical period for elk and the season when death losses are most likely to occur.