A fine-scale analysis of the temporal patterns influencing wildlife-vehicle collision risk

Wildlife-vehicle collisions (WVC) occur when vehicles and animals are present on the road at the same time. The risk can vary over the course of a day or year, depending on fluctuations in both traffic volume and the movement patterns of the species involved. This relationship has not been explicitly quantified at a fine temporal scale. To address this gap, we explore the relationship between hourly traffic volume and WVC occurrences involving crepuscular and nocturnal species. We calculated the relative traffic intensity for each hour of the day for a given road segment, allowing us to examine how dynamic patterns in traffic and wildlife activity interact to shape WVC risk. Our results indicate that WVC risk is better predicted by relative traffic intensity (i.e., hourly proportion of total daily traffic volume), than traffic volume (i.e., absolute number of vehicles per hour). The probability of a WVC occurring was highest when less than 3 % of the total daily traffic volume was on the road, regardless of the absolute traffic volume and road type. Importantly, the dirunal WVC risk changes over the year as the synchrony between animal movement and commuter traffic changes. We demonstrate that fine-scale temporal traffic patterns and species-specific activity periods are important to consider when assessing WVC risk. These findings contribute to a better understanding of the complex dynamics between traffic volume and wildlife behaviour, underscoring the need for nuanced mitigation strategies.