Effects of opening winter enclosures on red deer movement and local browsing pressure: An experimental assessment

Winter enclosures are an important wildlife management tool in mountainous regions of Central Europe. They are implemented to reduce browsing pressure and bark peeling caused by red deer (Cervus elaphus) during winter by lowering their numbers in the surrounding landscape. However, the enclosures require high levels of maintenance and increase local animal densities, which could potentially enhance the spread of diseases and parasites. Therefore, it is of great interest to evaluate the effectiveness of winter enclosures in restricting red deer movement and minimizing browsing damage. Thus, this study employs an experimental approach to analyse the impact of winter enclosure management on these two parameters in the Bohemian Forest Ecosystem. Three treatments were implemented: (1) four winter enclosures kept closed (regular management), (2) four winter enclosures opened earlier (opened earlier), and (3) two winter enclosures left open all winter (open fences).The median winter home range of red deer increased sixfold under the open fences treatment compared to the previous year, though the home ranges still did not extend beyond the borders of the protected area. At the same time, browsing probabilities for all tree species decreased in the vicinity of the enclosures in the open fences treatment. No change in browsing probability was observed around the enclosures opened earlier compared to the previous year. These results suggest that the main factor contributing to changes in browsing pressure caused by the experimental treatments was that red deer overwintering outside the open fences enclosures gained access to supplementary feeding in winter, consequently reducing their browsing activities in the vicinity of these enclosures. Therefore, winter enclosures may not always outperform unfenced feeding stations as a management tool to reduce browsing pressure.