A Growing Moose Population Is Threatening Rocky Mountain National Park’s Wetlands

Though moose are now considered a staple of Rocky Mountain National Park’s wildlife, they aren’t actually native to the area. Their growing population and large appetites have some conservationists worried about the impact to struggling wetland ecosystems in the park. 

Historically, moose would stick to the northern Rockies and only occasionally wandered down to Colorado. In 1978, moose from Utah and Wyoming were relocated to North Park, Colorado to increase hunting and wildlife viewing opportunities. Within a few years moose had an established population in Rocky Mountain NP. 

Moose populations thrived without natural predators like wolves and grizzly bears, which were eradicated from Colorado in the 1940s and 1953, respectively. Until about a decade ago, moose rarely ventured outside of Kawuneeche Valley. Today, moose are present in all watersheds in RMNP. 

“From 2014 to 2021, [Colorado Parks and Wildlife] statewide population estimates jumped from ~2,400 to ~3,500 animals, representing a 45% increase in 8 years,” according to RMNP’s website. 

Moose impact on the park’s wetlands

An adult moose in the Kawuneeche Valley can eat up to 60 pounds of vegetation each day. Their preference for river willows and other aquatic vegetation is now threatening the already struggling wetland habitats in the park. Elk, which were reintroduced in 1913, also contribute to wetland degradation. 

In recent years, willow have been a focus for park management because they are key components of a willow-beaver wetland ecosystem. Beavers both eat willow and use the stalks to create their dams, which provide habitat for a multitude of other water-loving species.

With an already struggling beaver population, the lack of food and building materials make it difficult for the species to make a comeback. Recent park surveys suggest that beavers occupy only 10% of the most suitable stream side habitat in the park.

Ongoing restoration

In an effort to conserve these wetlands, the Kawuneeche Valley Restoration Collaborative was formed in 2020. The collaborative developed restoration plans in an effort to improve water quality, strengthen the valley’s resiliency to climate change, enhance the aesthetics and recreational value of the area, and more. 

To achieve these goals, the team has fenced off areas of vegetation to prevent moose and elk grazing, planted native vegetation, and installed simulated beaver structures to restore water levels. 

The hope is that the results of their efforts in Kawuneeche Valley would be replicated in other areas of the park.