Fifth European Dirofilaria and Angiostrongylus Days (FiEDAD) 2016

Peer reviewe

Species distribution modeling for the invasive raccoon dog (Nyctereutes procyonoides) in Austria and first range predictions for alpine environments

Species distribution models are important tools for wildlife management planning, particularly in the case of invasive species. We employed a recent framework for niche-based invasive species distribution modeling to predict the probability of presence for the invasive raccoon dog (Nyctereutes procyonoides) in Austria. The raccoon dog is an adaptive, mobile and highly reproductive Asiatic canid that has successfully invaded many parts of Europe. It is known to occur in Austria since 1963 and is now widespread in the northern and eastern parts of the country, but its population density remains low. With the help of a species distribution model we identified focal areas for future monitoring and management actions, and we address some management implications for the raccoon dog in Austria. We also determined the environmental predictors of raccoon dog distribution in this alpine country. Its distribution seems to be mainly limited by climatic factors (snow depth, duration of snow cover, winter precipitation and mean annual temperature) and is thus linked to elevation. Consequently, we assumed the Alps to be a barrier for the spread of the invasive raccoon dog in Europe; however, its ecological permeability is expected to increase with ongoing climate change

Environmental drivers of raccoon (Procyon lotor L.) occurrences in Austria - established versus newly invaded regions

As we are faced with the imminent spread of the raccoon (Procyon lotor L.), a successful and highly adaptable invader in Europe, it is necessary to identify the drivers of its distribution and focal areas of its future management. Being an omnivorous species, raccoons can exert considerable influence on prey species of various taxa. Species distribution models for this invasive species can be useful tools for its management. Using a presence-only model (MaxEnt) based on environmental variables selected by raccoon experts, the presence of raccoons in Austria was predicted. Core areas of raccoon colonization are mainly located in and around cities and river valleys. Identified ecological drivers of raccoon distribution comprise climate and land-cover variables, with temperature parameters (e.g. the number of hot days, mean January temperature), the proportion of coniferous forests, settlements and elevation mainly influencing the model output. The importance of habitat parameters changes with the stage of invasion. In Austria’s established regions, the probability of raccoon presence was best predicted by variables chosen by an expert of the raccoon’s native range, while the predictors chosen by an expert in its introduced range better reflected the situation in recently invaded regions. The significance of climate and land cover in understanding the probability of raccoon presence was shown