Publication Date

Spring 2023

Degree Type


Degree Name

Master of Science (MS)


Environmental Studies


Lynne Trulio


camera traps, mammals, mountain biking, Recreation disturbance, trail disturbance, trail management

Subject Areas

Environmental studies


Anthropogenic disturbance that results in habitat loss is the leading cause of the current extinction crisis. To mitigate loss of habitat, protected lands are dedicated to preserving ecosystems, but such areas often allow outdoor recreational activities. Research has shown negative impacts on a range of species from outdoor recreational activities, and there is little information about potential impacts of mountain biking on wildlife. Mountain biking and hiking tracking data from the social fitness app Strava Metro and data from a camera trap project in Marin County, CA, were analyzed to assess how mammal species’ spatial distribution, temporal activity, and richness respond to distance from trails and different levels of mountain biking and hiking. While Strava Metro data provided an index of trail use versus actual numbers, this data was valuable for comparing more trafficked verses less used trails. This research found that three diurnal/crepuscular species and one nocturnal/crepuscular species were attracted to trails but changed their behavior to use trails more often at night. Most of the mammals observed were found less frequently on high-use bike trials compared to low-use. The fact that most mammal species avoided high bike-use trails altogether or during the day indicates this type of use is impacting mammals. Managersshould consider how to maintain non-bike and non-recreation zones within open spaces to support mammal species and biodiversity.

Available for download on Monday, August 26, 2024