Quels sont les facteurs de risque de collisions entre véhicules et ongulés sauvages : analyse de données nationales françaises pour trois espèces de grands ongulés, le Cerf, le Chevreuil et le Sanglier

Collisions between vehicles and wild ungulates red deer (Cervus elaphus), roe deer (Capreolus capreolus) and wild boar (Sus scrofa) become a significant risk to road safety and there is no effective way to reduce them except fencing on motorways. There is currently no count of collisions throughout France, but between 2006 and 2010 the Guarantee Fund of compulsory insurance (FGAO) paid for the expenses of motorists who had suffered a collision with a wild ungulate. This exceptional dataset of 87,241 collisions recorded between 2007 and 2010 allowed us to analyze the distribution of collisions at the national level, differentiate the explanatory environmental factors for these three ungulate species in the same territory. Thus, the proportion of urban areas first and then human population density largely determined the occurrence of collisions with wild ungulates. However beyond a certain threshold of urbanization the frequency of collisions has decreased because too much anthroporopization limits the presence of favorable habitats for ungulates. It was found as expected that collisions in urban areas were more likely with wild boar. Indeed, in recent years, wild boar have tended to colonize areas difficult to hunt, such as brownfields and urban forests. In agricultural areas, there is a higher risk of collision with roe deer, at high altitude with red deer, in the south of France with holm oak forests with wild boar. There was a positive effect of increasing landscape diversity on the average number of collisions. In a highly fragmented environment ungulates move daily between quiet and feeding areas, and these movements may force them to cross roads, increasing the risk of collisions. These results show that mitigation measures should better take into account the species concerned in each risk situation.