Conservation Value of Wildlife Crossings: Measures of Performance and Research Directions

In the last ten years, there has been a surge of interest in the ecological effects of roads on landscape ecology and in devising means of reducing road impacts on wildlife populations. The number of wildlife crossings built in North America and worldwide has increased during the last decade and their design and performance as mitigation measures has received considerable attention. In this paper I will discuss current approaches to restoring connectivity across roads with wildlife crossing structures. Once in place, wildlife crossings must be monitored and evaluated to determine their conservation value and ecological performance. I discuss some guiding principles for planning and measuring performance of mitigation crossings for wildlife that consider a range of ecological goals, time-frames, and changes in landscape conditions. Last, cost-effective designs and integrated planning are seen as important areas to make significant advances in designing sustainable transport systems.