Squeezed between bottom up and top down control: Wild boar population dynamics respond to wildlife management and beech nut mast years in a mountainous forest ecosystem

Understanding the drivers of wild boar (Sus scrofa) population dynamics is essential for effective management in European landscapes where increasing densities drive human–wildlife conflict. We analysed 13 years (2010–2023) of long-term harvest, environmental, and resource-availability data from the Bavarian Forest National Park, Germany, to quantify the relative roles of hunting quota, beech mast production, winter severity, and large carnivore presence in shaping annual population growth. Population growth was modelled using a Gompertz framework with generalised linear models and AICc-based model selection. The top-ranked model included previous-year harvest and current-year beech mast, and explained the majority of interannual variation in growth. The previous harvest exerted a strong negative effect on population growth, while beech mast had a strong positive effect. Winter severity and wolf presence received little empirical support after accounting for harvest and mast. Although a harvest × mast interaction model received some support, the interaction term was not significant, indicating that mast and harvest act largely additively rather than interactively. Our results demonstrate that harvest can be mechanistically effective under average conditions but is structurally vulnerable to pulsed, bottom-up resource forcing from beech mast. We show that predictive, mast-informed harvest can substantially improve management outcomes and reduce the risk of delayed, mast-driven population irruptions and associated damage in adjacent agricultural lands.