Using Wildlife-Vehicle Collision Records to Inform Wildlife Corridor Planning.

Abstract

Wildlife-vehicle collisions (WVCs) impose serious and increasing environmental, economic, and societal costs worldwide. Examining temporal and spatial patterns in WVCs is a critical piece of the wildlife connectivity puzzle that can help reduce the frequency and severity of collisions for humans and wildlife. We analyzed WVC records in New Hampshire (USA) between 2002 and 2019 to visualize spatiotemporal patterns, evaluate statistical predictors of WVCs, and to identify priority areas for mitigation efforts. More than 27,000 WVCs were reported between 2002 and 2019 throughout the entire state, averaging approximately 1500 WVCs per year. WVCs occurred on roads of all functional classes; notably, 33% occurred on "local" roads and at least 62% on roads with posted speeds greater than 40 mph. We calculated road-level metrics, including total WVCs and WVC density (i.e., WVCs per mile) over predefined, multiyear period and compared these metrics over space and time. Positive relationships were observed between WVCs and local road density, which corresponds to population centers within the state; however, only temporal factors were of practical significance in explaining WVC frequency. To inform statewide mitigation measures, we ranked roads based on WVCs per mile and total WVCs and identified the top 5% road for each during the most recent time periods.