Roosevelt elk, the largest subspecies of elk in North America, inhabit the Pacific Northwest’s temperate rainforests and coastal mountains. They are herbivores, meaning their diet consists entirely of plant matter. Their varied diet is fundamental for their survival, providing the necessary energy and nutrients to thrive within their diverse habitats.
Main Dietary Components
Roosevelt elk primarily eat a range of vegetation. They consume various grasses, which form a significant part of their forage, particularly in open areas. Forbs, which are broad-leaved herbaceous flowering plants, also make up a substantial portion of their diet. Examples of forbs they might eat include clover, vetch, and various types of wild pea.
Beyond ground-level vegetation, Roosevelt elk browse on shrubs and tree components. They consume the leaves, twigs, and bark from species like willow, huckleberry, salmonberry, and vine maple. Conifer needles and shoots, especially from Douglas fir and western hemlock, are also part of their diet. Their ability to utilize such a wide array of plant types allows them to adapt to different foraging environments.
How Diet Changes Seasonally
The availability of food sources influences the Roosevelt elk’s diet shifts throughout the year. In spring and summer, when vegetation is lush, their diet is rich in high-protein grasses and succulent forbs. This period of plentiful, nutritious forage allows them to build up fat reserves and support reproductive needs. The new growth provides easily digestible nutrients crucial for lactation in cows and antler growth in bulls.
As fall progresses, the quality and quantity of green plants decline. Roosevelt elk transition to more woody browse, such as twigs, evergreen leaves, and bark. They also rely on dried grasses that retain some nutritional value. This dietary shift helps them maintain energy through the colder months when food is scarcer and their metabolic needs change.
Feeding Habits and Ecological Role
Roosevelt elk employ distinct feeding habits, primarily grazing and browsing. Grazing involves consuming grasses and other low-growing herbaceous plants, often in open meadows or clearings. Browsing, conversely, refers to eating the leaves, twigs, and bark from shrubs and trees, typically in more forested or brushy areas. Their daily feeding patterns involve periods of foraging interspersed with rumination, where they chew their cud.
These feeding behaviors mean Roosevelt elk act as “ecosystem engineers.” Through their grazing and browsing, they influence the composition and structure of plant communities. Their selective foraging can reduce the density of certain plant species while promoting the growth of others. This activity also impacts forest regeneration by browsing on tree saplings.