Monitoring of outdoor winter recreation using Unmanned Aerial Vehicles (UAV) in the Beverin Nature Park, Switzerland

Increasing winter recreation in mountainous protected areas poses challenges for conservation and visitor management. This study explores the use of Unmanned Aerial Vehicles (UAVs) to monitor spatial behaviour of winter recreationists in the Beverin Nature Park , Switzerland. High-resolution orthophotos were generated from a fixed-wing UAV flight and analysed using contrast-based feature extraction to detect ski and snowshoe tracks. The results show a high concentration of use along designated routes and limited intrusion into protected wildlife areas, indicating largely compliant behaviour. However, the analysis also revealed deviations from official trails in topographically attractive areas. The method proved effective under favourable snow and light conditions, but its sensitivity to environmental variability limits temporal generalisability. UAV surveys represent momentary snapshots and cannot reflect full-season dynamics. Multiple flights across a winter season are therefore recommended to capture temporal patterns more robustly. Additionally, the ecological sensitivity of the monitoring process itself must be considered: flight planning was conducted in close coordination with local wildlife authorities to minimize disturbance, as UAVs can affect fauna during energy-critical winter periods. UAV-based monitoring offers a spatially explicit and non-invasive method for assessing recreation patterns and evaluating visitor guidance. Future developments should focus on multi-temporal survey designs and automated image classification to improve robustness under varied conditions. Coordinated implementation with wildlife management is essential to ensure both technical effectiveness and ecological responsibility.