Evaluation of measures to minimize wildlife-vehicle collisions and maintain wildlife permeability across highways in Arizona, USA

  • Published source details Dodd N.L., Gagon J.W. & Schweinsburg R.E. (2003) Evaluation of measures to minimize wildlife-vehicle collisions and maintain wildlife permeability across highways in Arizona, USA. Proceedings of the 2003 International Conference on Ecology and Transportation, Center for Transportation and the Environment, North Carolina State University, Raleigh NC, USA, 353-354.


This study is summarised as evidence for the following.

Action Category

Install barrier fencing and underpasses along roads

Action Link
Terrestrial Mammal Conservation
  1. Install barrier fencing and underpasses along roads

    A before-and-after study in 2002–2003 along a highway in Arizona, USA (Dodd et al. 2003; same experimental set-up as Dodd et al. 2006) found that two open-span bridge underpasses, in areas with roadside elk-proof fencing, were used by elk Cervus canadensis but not by white-tailed deer Odocoileus virginianus and vehicle-deer collisions did not decrease after installation. A total of 181 collisions were reported, with no difference in rates along the section before and after the two underpasses were constructed. GPS collars recorded 675 highway crossings by elk, only 6% of which were through underpasses. Overall, 62% of 1,435 elk, but only 0.4% of 257 white-tailed deer recorded on cameras at underpasses crossed through them. Two open-span bridge underpasses (<250 m apart) along the State Route 260 highway were monitored using video cameras and track counts (inside and 60 m from entrances). Cameras were also installed at the ends of the short sections of elk-proof fencing. Thirty elk were tracked using GPS collars (May 2002 to July 2003). Vehicle-deer collisions were recorded before and after underpass installation.

    (Summarised by: Rebecca K. Smith)

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