Recreational activities and human hunting strongly influence red deer space use to trails

Assessing how animals adjust their movements to two widespread human activities, hunting and recreation, can provide critical insights into how these activities reshape red deer spatial behavior. In this study, we used GPS telemetry data from red deer in the Bavarian Forest National Park (Germany) to analyze their habitat selection and displacement in relation to hiking trails with varying visitor numbers. Using integrated step selection analyses, we looked at different human disturbances for four scenarios (nonhunting season, hunting season, day, and night). Despite research on the combined effects of hunting and recreation on ungulates, how responses vary between day and night and across areas with varying levels of human disturbance remains poorly understood. By incorporating visitor numbers, this study provides a novel perspective on how red deer adjust their behavior to recreational intensity. We hypothesized that red deer individuals would avoid trails, avoid crossing trails, increase their displacement, and select habitats with dense understory vegetation during periods of greater human disturbance (i.e., during the day and hunting season). We expected this effect to be stronger within areas with high visitor numbers during the day and within the hunting zone during the hunting season. We found that red deer avoided trails during the day, with a stronger avoidance of trails with high visitor numbers and favored denser vegetation for concealment during daytime. Trails were increasingly avoided with distance from trails, areas further away from trails were selected when visitor numbers were high, and step length was minimally higher close to trails. The strong aversion to crossing trails suggests that trails act as barriers, influencing displacement and habitat use. Our results demonstrate that trails associated with varying levels of human presence are important features shaping red deer displacement and habitat selection. These behavioral modifications might cause cascading ecological effects, that is affect vegetation and nutrient dynamics, underlining the importance of visitor management such as spatial zoning, temporal access limitations, and modifications of trail networks to mitigate impacts.