Reconnecting fragmented habitats is a growing priority as we realize the effects of millions of miles of roadways dissecting the natural world. In addition, shifting ranges and movement patterns of wildlife due to the effects of climate change are accelerating the need for ecologists, landscape architects, and engineers to develop solutions for new road construction projects and existing roads to increase connectivity for wildlife and decrease wildlife-vehicle collisions (WVCs). A new article by Lister et al. in the Frontiers in Ecology and the Environment discusses the importance of wildlife-crossing infrastructure, the challenges and benefits to their implementation, and solutions for the future.
The authors state that although wildlife crossings are effective in mitigating WVCs and facilitating safe movement of wildlife between fragmented habitats, there are still substantial barriers to their implementation due to perceived economic and policy reasons. However, they argue that full-cost accounting of the cost of WVCs (vehicle repair, medical, insurance, carcass disposal, etc.) is necessary to assess costs and benefits of wildlife crossings.
This article provides a comprehensive argument in favor of implementing wildlife crossing infrastructures that will best serve current and future wildlife distributions and movement patterns across road-fragmented landscapes. They bring attention to the engineering and architecture challenges of wildlife crossing designs that are needed to adapt to the changing movements of wildlife.
Lister et al. highlight innovative projects such as those from the (ARC) Animal Road Crossings International Wildlife Crossings Infrastructure Design Competition. This competition emphasized the need for more innovative designs that reduce cost, time, and difficulty in the construction of the wildlife-crossing infrastructure. The ARC competitors were given a tough challenge of designing crossings that met human and wildlife concerns and the result was a great success in advancing this area of wildlife conservation by diluting the economic concerns and bringing greater public awareness of the issue. The winning design by HNTB Engineering and Michael Van Valenburgh Associates Inc, created an economical overpass design that uses prefabricated pieces that reduce the transportation and construction costs. This design also allows flexibility after construction, making it possible to adapt to future changes.
In conclusion, the authors expressed a dire need for adaptive approaches, political leadership, and transparent accounting in order for wildlife-crossing infrastructures to become implemented broadly.