Temporal patterns of wild boar-vehicle collisions in Estonia, at the northern limit of its range

Collisions with large ungulates are considered to be a serious problem in many countries over the world. These incidents create a rising concern in traffic safety and cause extensive ecological and economical damage. In this paper, we investigate temporal distribution of wild boar-related traffic accidents-seasonal, weekday and diurnal patterns. We analysed 918 collision reports collected by Estonian environmental emergency hotline, police and insurance companies during 2004-2013. Notable increase in wild boar abundance and harvest numbers appeared during the study period, leading not only to higher road collision risk but also having been referred to African swine fever emergence in the area. Our results suggest that the highest risk for collision is in October, November and December. More wild boar-vehicle collisions (WBVCs) occur during weekends with a peak on Friday probably due to higher traffic volumes. Regarding diurnal patterns, most of WBVCs occur after sunset, and the frequency of collisions remains high until late night. Knowledge about temporal patterns of WBVCs is important, as it may help to improve suitable mitigation measures.