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Other publication, 2016

Are animal-vehicle collisions a random event? – Analysis of the spatial distribution of accident data.

Seiler, Andreas; Andrášik, Richard; Sjölund, Magnus; Rosell, Carme; Torrellas, Marina; Sedoník, Jiří; Bíl, Michal; Jägerbrand, Annika

Abstract

Ungulate-vehicle collisions (UVC) in Sweden are an increasing traffic safety issue, causing an escalating loss in wildlife and a growing socio-economic burden that is not in relation to the changes in ungulate population sizes and hunting statistics. Conventional prevention methods appear as little cost-effective and both Transport and Wildlife administrations call for better targeted mitigation strategies. An essential requisite for this is a good understanding of how accidents are distributed and where they aggregate. Since 2010, car drivers are legally obliged to report any UVC to the police and a majority of these reports is followed-up by contracted hunters who take care of the wounded or dead animal and report the exact accident location. We present a thorough analysis of these hunters’ reports, using a modified kernel density estimation technique (KDE+) to identify significant clusters in accident frequencies and compare their spatial coherence between ungulate species and between years. During the 5-year period of 2010 to 2014, some 79000 accidents with roe deer (Capreolus capreolus), 19000 with moose (Alces alces), 11000 with wild boar (Sus scrofa) and 7000 with fallow deer (Dama dama) or Red deer (Cervus elaphus) have been reported by hunters in Sweden. Of these, 30% to 45% were distributed in a significantly aggregated pattern. UVC clusters covered less than 3% of the entire road network. Within these clusters, accident densities were on average 45 times higher than elsewhere on the roads. There were important differences in cluster locations between species and some differences between time periods as well. Factors associated with clustering can be generalize as providing increased attractiveness and increased openness of the road to wildlife. We conclude that, despite species specific and temporal differences in clusters, only a small portion of the road network needs to be mitigated by physical mitigation measures such as fences or fauna passages to affect a substantial part of UVC. Yet, for the remaining part of UVC that are not aggregated, a different mitigation approach is needed that corresponds to regional or global factors such as wildlife population densities or driver behaviour.

Published in

Title: International Conference on Ecology and Transportation, Programme and Abstracts
ISBN: 978-2-37180-153-0
Publisher: IENE and CEREMA