Temporal patterns of ungulate vehicle collisions in the Thunder Bay area

Abstract

Rising road densities, higher vehicle speed limits, and increased traffic volumes, combined with growth in the density of various deer species, have increased the risk of wildlife-vehicle collisions across the world. The result is a great deal of animal suffering, traffic safety problems and socio-economic costs. The objective of this investigation was to explore trends in vehicle collisions with moose and white-tailed deer in Thunder Bay and attempt to gain a better understanding of the temporal variation associated with collisions. Describing their temporal pattern allows for the development of measures to reduce wildlife-vehicle collisions. The monthly distribution of the 1,332 wild ungulate-related traffic accidents on regional highways in the Thunder Bay area occurring between January 2011 and December 2021 was not random; most occurred in May and June, coinciding with the breeding season when juveniles born the previous year are dispersing. The next most common months for accidents were October and November, coinciding with the rut. Averaged over the entire eleven years, daily peaks in accidents occurred more often during dawn and dusk hours, but the trend occurred only for two of eleven years, suggesting that peaks in deer and moose activity, which should correspond with these hours, are not consistently responsible for accident risk. Drivers can reduce collision risk and especially the risk of serious consequences by lowering their speed and by keeping alert for deer and moose.