Spring is a time when migrating wildlife combined with high-powered snowmobiles creates a situation ripe for conflict in Colorado’s national forests.

The calendar says it is now spring. Here in Denver temperatures are starting to show that we are getting back to our expected average weather after colder than normal spells in January and February and above average snow fall across large areas of Colorado. While many are looking forward to the end of winter and the beginning of spring, the high-country areas of the state are still receiving snow and many people are still using these areas for winter recreation. This includes snowmobiling, formally known as winter motorized recreation, and has huge impacts in wildlife emerging for spring forage after hibernation or animals, like elk for example, are moving to calving grounds.

Recent studies from Colorado Parks and Wildlife (CPW) have shown that elk populations are not recovering sufficiently in many locations, and that motorized vehicle use is adversely impacting the species, especially during the spring calving and fall rut periods.

In some places in the San Juan National Forest, CPW data from 2020 shows calf to cow ratios have been declining since 2006, and are currently under long-term averages. CPW biologists have stated that elk herd numbers in southwest Colorado are going down, and part of it is because of troubling calf numbers. Disturbances from snowmobiles can result in unneeded energy expenditures when these species are at their most vulnerable, and unnecessary displacement from desirable winter habitats to less desirable habitats can impact reproduction performance of these species.

CPW also recently recommended a full closure of the Haymaker Trail near Eagle due to recreation impacts on elk during the winter months. Elk calving season varies across the state but can start in April and go through June. According to the Theodore Roosevelt Conservation Partnership some one-third of critical winter habitat for elk herds in Colorado are impacted by motorized and non-motorized travel and in turn elk avoid the area due to recreational disturbance.  Snowmobiles followed later in the year by four-wheelers and mountain bikers are causing significant impacts to elk reproduction rates in Colorado.

Another iconic species – the endangered Canada Lynx (Lynx canadensis) –  is also being impacted by snowmobiles. While they can tolerate some level of disturbance from winter recreation activities including snowmobiling, recent studies in Colorado show that Lynx have already changed their behavior in response to motorized recreation. In particular, Lynx reduce their movement and become more nocturnal in the presence of winter motorized travel. It’s also concerning that newer snowmobiles can travel through deeper snow and in steeper terrain, allowing access to areas further away from roads. The tracks put down by these machines can also result in compacted snow allowing coyotes, which can be formidable competitors of Lynx, to reach habitat they would unlikely otherwise be able to enter. The influx of coyotes into Lynx habitat can reduce prey availability (almost exclusively snowshoe hare) for the cats.

Other species like bighorn sheep and mountain goat are also impacted by winter travel and snowmobiling near lambing sites. This can cause detrimental impacts to the species.  Due to the impacts of motorized use on important wildlife in Colorado, WildEarth Guardians is leading a campaign to ensure national forests throughout the state are adequately conducting travel management planning, including over-snow or winter travel planning and enforcement.

The 2005 Travel Planning Rule requires the Forest Service to designate areas that are open to over snow mechanized winter travel (e.g., snowmobiles). Many national forests, including those in Colorado, have continued to operate as if all areas of a forest are open to over-snow motorized travel unless specifically closed. The 2005 Travel Planning Rule made it clear that this was incorrect and the opposite was true.

Despite having almost two decades to implement this closed-unless-designated-open rule, most national forests in the United States have not gone through a Winter Travel Management planning process to identify and designate areas open for motorized winter travel. Because of this snowmobiling is permitted on the vast majority of national forest land in Colorado. Enforcement is often lacking in the few places where the rule has been implemented.

As such our goal is to ensure travel planning and again, in particular, winter travel planning, occurs on all Colorado national forests within the next five to ten years.  Guardians has already stepped up and is actively challenging the Forest Service to conduct winter travel planning for the Rio Grande National Forest. After a Notification of Intent to sue in 2022, the Rio Grande has committed to begin this planning in 2024. Our goal is to build on this progress, with the Rio Grande’s commitment being a first domino that pushes the Forest Service to conduct winter travel planning on all forests in the state.

Other national forests in the state have examined travel management in conjunction with the Land Management Plan (LMP) revision process. This includes the Grand Mesa, Uncompahgre and Gunnison (GMUG) National Forest, which is currently revising its LMP (aka Forest Plan). We expect other Colorado national forests to follow suit, with the Pike, San Isabel, Arapaho and Roosevelt National Forest starting their LMP revision process in the coming years. We will closely track and ensure winter travel is being considered during these LMP revision processes.

Guardians will be pushing the Forest Service to establish winter and summer travel plans and designations while implementing the correct interpretation of the 2005 Travel Management Rule on its’ Colorado forests. The future vitality of elk, Canada lynx, bighorn sheep, mountain goat, endangered Uncompahgre fritillary butterfly and other species depends on a reduction in motorized vehicle travel within national forests in Colorado.

If you’re concerned about Colorado’s wildlife and want to know how you can be a Guardian too, please sign up for our E-news to get the latest updates and action alerts about our work. We will keep you informed of opportunities to help us in the fight to protect wildlife and wildlands.

About the Author

Andrew Rothman | Wild Places Program Director, WildEarth Guardians

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