Assessment of roe deer (Capreolus capreolus L.) - vehicle accident hotspots with respect to the location of 'trees outside forest' along roadsides

Animal-vehicle collisions (AVCs) pose a serious threat to human and animal welfare, and result in increasing costs for society. Mitigation efforts have been in the focus of research for decades but have revealed only few generalities on where and why AVCs occur. Uncertainty therefore remains on how to make decisions regarding nature conservation, wildlife and transportation management. In our study, we used GPS data on almost 1000 AVCs between October 2014 and October 2016 involving roe deer (Capreolus capreolus L.) in the administrative district of Gottingen, Germany, to identify accident hotspots based on Kernel Density analysis. We then used information from a mapping campaign of trees outside forests (TOF), including hedges, bushes, groves, isolated trees and other non-forest vegetation to investigate whether TOF abundance is larger near accident hotspots when compared to areas showing no hotspots (assumed as reference area). We found that near hotspots, TOF are significantly more abundant than in the remaining reference area. We conclude that future transportation management should consider TOF management as a possible indicator for AVCs.