Trail Impacts and Seasonal Closures

Here’s some more information about trail impacts from human use and the efficacy of seasonal closures.

Impacts? What Impacts?
There’s an understandable misperception that the impacts of a trail are limited to the width of its tread, or the surface that users travel on. Actually, the significant ecological impacts are from the use it gets. As people travel along a trail, wildlife tend to alter their behavior, avoiding or outright abandoning the area. Each time a human passes by, animals’ stress levels can increase and they are less likely to spend time eating, caring for young or sheltering. For many species, survival is strictly a mathematical equation. Individuals feed as much as they can during the summer and fall, building up caloric reserves. During the winter, they are slowly starving. Human caused disturbance can lead to less time eating in the summer or fleeing in the winter (and possibly abandoning food) and unnecessarily burning calories.


Seasonal Closures

The idea is simple, at least in theory. Close an area when human presence would negatively impact animals (for example, disrupt them while they are calving or cause them to stop eating when they are trying to put on calories for the winter). People can use the trail for one part of the year, and wildlife for the other part. Unfortunately, in practice things aren’t that simple. Here’s where things get complicated:
1. It only takes a few violations to significantly impact animals’ survival and behavior, especially in critical habitat areas like calving grounds.
2. Enforcement is costly and challenging. While Pitkin County has a better track record on enforcement than federal agencies, the County has seen an increase in violations on the Rio Grand Trail and notes in their environmental report on the trail that in the Crystal Valley, “Closures in areas where there is limited enforcement capacity or multiple access points from private land (Red Wind Point and Avalanche Creek) have been less effective.”
3. Once built, a trail is forever. Seasonal closures are only as good as the political will and the funding to enforce them.
4. While a seasonal closure may reduce the impact, it is by definition only softening the blow. Trails through intact habitat decrease its value and use to wildlife, no matter how effective the closure. Seasonal closures should only be used as a last resort. And, there are certain places where the risk to wildlife from even a few violations means that a trail should simply never be built there.
If closures are used as a mitigation measure, they must include conditions that:

  • Legally guarantee their existence in perpetuity.
  • Fund their enforcement in perpetuity.
  • Guarantee enforcement will be frequent enough to result in a minimal number of violations.
  • Require complete closure of all or portions of the trail if violations surpass a certain threshold.