Maintaining opportunities for outdoor recreation while balancing sustainable use of natural resources presents a challenge for natural resources managers in the face of rapidly increasing recreational use. Outdoor recreation provides health and well-being benefits to humans and is often perceived as having neutral ecological impacts on wildlife and the environment. Human recreation, however, disrupts many aspects of wildlife ecology by triggering trade-offs between avoidance of perceived risk and spending time in other fitness-enhancing activities such as foraging. In the presence of human recreation, ungulates could spend more time in vigilant behavior, which could lead to lowered fitness in the long term. We deployed wildlife cameras to explore how recreation volume, the type of recreation, and the distance from trails influenced the probability of vigilance in ungulates. Mule deer (Odocoileus hemionus) and Rocky Mountain elk (Cervus canadensis) vigilance was highly dependent on recreation volume, distance to the trail, and environmental variables. Ungulate species increased vigilance as recreational volume increased. Environmental factors potentially alleviated recreation impacts in certain circumstances however the level of recreation use facilitated higher levels of vigilance in ungulates. The use of wildlife cameras to collect human recreation and wildlife behavior data should be further explored for use in wildlife studies. Additional study in compounding direct and indirect factors of recreation is needed to more fully understand recreational influences on ungulate vigilance.
