: Moose have wandered into Colorado occasionally, but there was no breeding population until animals were introduced to North Park from Utah and Wyoming in 1978 and 1979. Populations have expanded to nearby counties (and Rocky Mountain National Park), and animals have been transplanted to the Upper Rio Grande drainage and Grand Mesa. Individual moose may also wander widely from their usual mountain haunts, to the edge of the plains, for example, where they sometimes graze alongside cattle.
Their body is covered with black or very dark brown hair. They have a very large head with a dewlap of skin, called a “bell,” hanging down from the jaw. Moose have very long legs so they can wade into a lake and eat plants off the bottom. Their legs enable them to paw through deep snow to reach food in winter.
Moose are the largest deer; bulls range to 9 1⁄2 feet long (of which only four inches is tail), six feet tall at the shoulder, with weights to over 1,000 pounds. Antlers are “palmate”— flattened like a hand. Antlers of bulls in their prime may weigh over 50 pounds. Antler growth begins late winter with the formation of soft “velvet,” the blood-rich skin that nourishes antler growth. Velvet is rubbed off in fall in preparation for the breeding season. Moose are mainly found as singles or in small groups, not in large herds.
Range: In Colorado, moose are most often found in North Park, but have been sighted in Middle Park, Rocky Mountain National Park, South Park, near Leadville, near Gunnison, near Yampa, northwest of Creede, south of Fraser, near Colorado Springs, and in Golden, west of Denver.
Habitat: Moose live in forested areas that are often close to lakes and marshes. They are very territorial, will defend their space, and rarely leave their home territory during winter.
Diet: During the winter they are browsers mainly feeding on willows, also serves as shelter in the summer they graze on grasses, forbs, underwater vegetation, and bushes. They also graze on coniferous needles and deciduous leaves in the summer.
Reproduction: Gestation period is about eight months. Moose breed in late September and early October. The adult males spar with their antlers and can be extremely aggressive and dangerous. During breeding season is one of the few times they form small groups.
Calving occurs in late May through early June. Calves are born with a reddish brown coat (no spots) that darkens with age. The cows often have twins.
Notes of interest: Moose are excellent swimmers. In the winter they remain in their territory, often in willow marshes, and form “yards”- they create paths in the deep snow as they paw for food. Moose are very large, fast animals and are aggressive when disturbed.
Moose are semi-aquatic, wading to feed on aquatic plants and willows in summer. Some ranchers in North Park welcomed the moose as a control on willows, which invade irrigated hayfields, but in winter moose may turn to grazing and thus compete with domestic livestock as well as elk.
For more information, see:
By David M. Armstrong
Department of Ecology & Evolutionary Biology
Environmental Studies Program, University Museum of Natural History
University of Colorado-Bouldermausmann@aol.com