Factors influencing wild boar presence in agricultural landscape: a habitat suitability modelling approach

The wild boar (Sus scrofa L.) population has increased in most parts of Europe during the last three decades. As a consequence, population distribution ranges have shifted to more agricultural areas. These newly colonized areas are characterized by highly fragmented forest cover and a preponderance of crop fields and grasslands, thus increasing the risk of problematic interactions with farming activities and small game species. Although plasticity of wild boar to various environmental conditions is well known, understanding the ecological patterns that promote the density distribution of the species within agricultural areas remains of importance for adapted management strategies within these landscapes. Inside a recently occupied area (between 10-30 years of wild boar regular presence) of southern Belgium, we studied the relation between occurences of wild boar population, estimated by hunting bag and crop damages, with a set of environmental, anthropic and landscape variables. We used Maximum Entropy (MaxEnt) approach to analyze the data. Considering the main factors known to favour wild boar distribution, we hypothesized that crop fields providing cover and food, deciduous forest (providing mast) and water stream density are the main factors influencing the wild boar density distribution. The results are used to derive a habitat suitability map of wild boar distribution in northern Wallonia where wild boar recently starts to spread.