Rocky Mountain National Park (RMNP) is a vast landscape defined by dramatic elevation changes, creating a mosaic of environments that support a rich variety of wildlife. The park’s diverse ecosystems, ranging from low-lying montane meadows to exposed alpine tundra, provide habitat for 66 species of mammals and over 280 species of birds. This mountainous area serves as a natural sanctuary for creatures adapted to high-altitude living, offering visitors exceptional opportunities to observe animals in their natural settings.
The Iconic Large Mammals
Rocky Mountain National Park is perhaps most famous for its large ungulates, which are frequently seen in the park’s expansive meadows and valleys. The Rocky Mountain elk is the most abundant large mammal, with large herds often grazing in areas like Moraine Park and Horseshoe Park. The best time to observe these animals is during the fall rut, which peaks from mid-September through mid-October. This period is marked by the haunting bugle of the bull elk, used to challenge rivals and attract females.
Moose are becoming a more common sight, primarily on the park’s west side in the Kawuneeche Valley. These massive animals prefer riparian zones, or wetland areas, where their diet consists heavily of willow and aquatic vegetation. Visitors can often spot moose feeding near the Colorado River headwaters. Unlike elk, moose are generally solitary and should be given a wide berth due to their unpredictable and defensive nature.
Bighorn sheep are masters of the high, rocky terrain. They are most predictably seen in the late spring and early summer near Sheep Lakes in Horseshoe Park, where they descend to ingest minerals from the soil. The male rams are recognizable by their massive, curled horns, which can weigh over 30 pounds. They inhabit the rugged slopes of the Mummy Range and the Continental Divide.
Mule deer are the most widely distributed and commonly sighted deer species. They inhabit the montane regions, frequently seen browsing on shrubs and forbs in open areas and along the edges of the forest. They are most active at dawn and dusk, and they can be identified by the characteristic bounding gait they use when startled to navigate uneven ground.
Wildlife Across Elevation Zones
The park’s ecosystem diversity is best understood by dividing it into three distinct elevation zones, each hosting specialized wildlife.
Montane Zone (7,000 to 9,000 feet)
The Montane Zone, characterized by ponderosa pines and open meadows, is home to the park’s predators and forest birds. Coyotes are regularly sighted in these open areas and forest edges, where they hunt small rodents and rabbits. Although black bears are present in the park, they are generally rare and elusive. Bears prefer the dense cover of thick vegetation in both the Montane and Subalpine zones.
Subalpine Zone (9,000 to 11,000 feet)
The Subalpine Zone, marked by dense forests of Engelmann spruce and subalpine fir, supports a different community of mammals and specialized birds. The elusive Pine Marten is an agile climber found in these mature conifer forests. Martens are mostly nocturnal, but they may be seen hunting small mammals, such as the Snowshoe Hare. Snowshoe hares are well-adapted to this snowy environment, possessing large, fur-covered hind feet and a coat that changes color seasonally for camouflage.
Alpine Tundra Zone (Above 11,000 feet)
Above the treeline lies the harsh Alpine Tundra Zone. The American Pika thrives in the talus slopes and rock fields of the tundra. Pikas do not hibernate, instead spending the short summer months collecting vegetation to create “haystacks” for their winter food supply. They are often heard before they are seen, emitting a distinctive high-pitched alarm call that echoes across the rocks.
Yellow-bellied Marmots are large ground squirrels commonly seen sunning themselves on rocks along Trail Ridge Road. They use a loud, sharp whistle to alert their colony to danger before retreating into their burrows. The White-tailed Ptarmigan is the only bird to live year-round in the alpine zone. Its plumage changes seasonally from speckled brown to pure white, providing perfect camouflage against the snow.
Viewing Wildlife Responsibly
Encountering wildlife is a highlight of visiting Rocky Mountain National Park, but maintaining a safe distance is paramount for visitor safety and animal welfare. Visitors must stay at least 75 feet away from all wildlife, including elk and bighorn sheep. This distance increases to a minimum of 120 feet for potentially more dangerous animals like moose, black bears, and mountain lions. A simple way to judge this distance is to use the “Rule of Thumb”: if you cannot cover the animal with your thumb when your arm is extended, you are too close.
Feeding any animal in the park is strictly prohibited, as it causes wildlife to lose their natural fear of humans, leading to aggressive behavior. Visitors should secure all food and scented items, including toiletries and trash, in bear-resistant containers or hard-sided vehicles, especially when camping. When a wildlife sighting causes traffic to slow or stop, travelers should use designated pull-offs and never stop in the middle of the road.