Wildlife-Vehicle Collision Mitigation for Safer Wildlife Movement Across Highways: State Route 260.

摘要

Researchers investigated wildlife-highway relationships in central Arizona from 2002 to 2008 along a 17-mile stretch of State Route (SR) 260, which is being reconstructed in five phases and will have 11 wildlife underpasses and 6 bridges. Phased reconstruction allowed researchers to use a before-after-control experimental approach to their research. The objectives of the project were to: (1) Assess and compare wildlife use of underpasses (UPs); (2) Evaluate highway permeability and wildlife movements among reconstruction classes; (3) Characterize wildlife-vehicle collision (WVC) patterns and changes with reconstruction; (4) Assess relationships among traffic volume and WVCs, wildlife crossing patterns, and UP use; and (5) Assess the role of ungulate-proof fencing with WVCs, wildlife UP use, and wildlife permeability. Researchers used video surveillance to assess and compare wildlife use of six UPs, at which 15,134 animals and 11 species were recorded; 67.5 percent crossed through UPs. Modeling found that UP structure type and placement was the most important factor influencing the probability of successful crossings by elk (Cervus elaphus) and Coues white-tailed deer (Odocoileus virginianus). Researchers used Global Positioning System (GPS) telemetry tracking of 100 elk and 13 white-tailed deer to assess and compare permeability. Elk permeability on reconstructed sections was 39 percent lower than controls, while deer permeability was 433 percent higher on reconstructed sections. The elk-vehicle collision (EVC) rate on fenced reconstructed sections was the same as before-reconstruction levels, but on unfenced sections the EVC rate was nearly four times higher. In addition to a safer and more environmentally friendly highway, the economic benefit from reduced EVCs on SR 260 averaged $2 million/year since the completion of three reconstructed highway sections.