A spatiotemporal analysis of ungulate–vehicle collision hotspots in response to road construction and realignment

MacDougall, Sandra; Bíl, Michal; Andrášik, Richard; Sedoník, Jiří; Stuart, Esther · 2024 · DOAJ

DOI: 10.5751/ES-14883-290201

archive: archived pipeline: cataloged verified

Get this paper ↗ (DOI — opens at the source; we link to it, we don't host it)

Summary

This study evaluates the spatiotemporal evolution of ungulate–vehicle collision (UVC) hotspots in response to major road construction and realignment in Alberta, Canada. Motivated by the negative environmental impacts of roads and the public safety risks posed by collisions with large-bodied wildlife, the research aims to assess how infrastructure changes affect UVC rates and hotspot stability. The authors address a gap in existing literature, which often relies on short-term, geographically limited studies lacking inferential strength, by employing a novel analytical approach that monitors collisions over both space and time. The researchers conducted two case studies using government police collision and carcass data from 2000 to 2021. Case Study 1 examined a highway bypass adjacent to Calgary, comparing a 4.5 km section of a new fenced highway with wildlife underpasses against an unfenced control highway. Case Study 2 analyzed a 54.5 km segment of Highway 63 in rural Alberta, which was converted from a two-lane to a four-lane divided highway with an increased speed limit but no wildlife mitigation measures. The study utilized Kernel Density Estimation Plus (KDE+) to identify spatial hotspots and a novel spatiotemporal modification (STKDE+) to track hotspot stability, emergence, and disappearance over time. Before-after and control-impact analyses were performed to assess changes in UVC rates, accounting for traffic volume and wildlife population trends. The results demonstrated that wildlife mitigation measures significantly reduced collisions at the local scale. The fenced bypass in Case Study 1 resulted in an 86% reduction in UVCs compared to the unfenced control highway, with a large effect size. However, the study identified a "fence-end effect," where a new hotspot emerged at the southern edge of the fencing, and noted that high traffic volumes on the bypass created a barrier effect, shifting collision risks to weekends. In contrast, Case Study 2 showed that widening the highway without mitigation led to a slight, non-significant increase in UVCs and the reemergence of the majority of historical collision hotspots. The STKDE+ analysis successfully distinguished between stable hotspots and those that shifted or disappeared in response to construction. The findings highlight the critical importance of scale in evaluating wildlife mitigation. While fencing and underpasses effectively reduce direct mortality on specific segments, their net benefits can be negated by regional road density and proximity to unmitigated high-volume roads. The study concludes that transportation planning must incorporate wildlife considerations across multiple scales and that spatiotemporal monitoring tools like STKDE+ provide valuable insights into the long-term effectiveness of mitigation strategies, helping to identify persistent risk areas and the unintended consequences of infrastructure changes.

Provenance

The full processing record for this entry. Every stage of this paper's journey through the pipeline is logged — what ran, with which tool and model, how many attempts it took, and when it last completed.

Summary generated by qwen3.6-27b-prismaquant on 2026-06-26; verification: verified.

Topics

Ranked by relevance to this paper. Hover a topic for its definition.

• roadway lighting effects