WTI Researchers are
collaborating on a research project to develop, implement and evaluate a
wildlife crossing structure made of Fiber-reinforced polymers (FRPs), a strong
but lightweight composite material that could significantly reduce the
construction and maintenance costs of wildlife overpasses and associated
infrastructure elements. In recent
project news, an FRP wildlife crossing will be designed for a location on US Highway
97 in Siskiyou County, California – the first of its kind on this continent.
The project has evolved out of several research collaborations at WTI. In May 2018, WTI and its partners, Ryerson University in Toronto, Canada, and ARC (Animal Road Crossing) Solutions hosted a design collaboration laboratory (Co-lab) on FRP-based wildlife crossing structures. The Co-lab engaged experts in engineering, landscape architecture, and ecology from across North America and set the stage for further exploration of FRP material use in wildlife crossing infrastructure.
Also, in 2019 WTI was selected to lead a team of researchers for a Transportation Pooled Fund Study (PFS) administered by the Nevada Department of Transportation and co-sponsored by the State Departments of Transportation of AK, AZ, CA, IA, MN, NM, OR, and WA, as well as Ontario’s Ministry of Transportation and Parks Canada Agency. The FRP structural design, implementation and evaluation will be conducted as part of the Pooled Fund Study. Marcel Huijser is the PI for the overall Transportation Pool Fund Study, which will identify a range of cost-effective solutions to reduce wildlife-vehicle collisions. Matthew Bell, Damon Fick and Rob Ament are leading the FRP design project component; Mat had the opportunity to present a poster on FRP research at the TRB Annual Meeting in Washington, DC in January 2020.
The Idaho Transportation Department is currently considering wildlife crossing structures for a segment of U.S. 20 near Island Park. High Country News recently published an extensive feature article exploring both support and opposition to this proposal: “When wildlife safety turns into fierce political debate.” WTI Road Ecologist Marcel Huijser was interviewed for the article, discussing the potential role and effectiveness of animal detection systems. The article also cites his research on the costs to society of vehicle crashes with deer and other large mammals.
One of the country’s leading newspapers consulted a WTI researcher and several of our road ecology publications for a national feature story on wildlife crossings. “Retrofitting busy highways to let wildlife travel safely, too” explored national and state initiatives to identify wildlife corridors and enhance crossing structures such as underpasses and overpasses. The Post interviewed Road Ecology Program Manager Rob Ament, who discussed the potential long-term genetic consequences of highways that restrict wildlife movement and connectivity. The article also cites WTI/Montana Department of Transportation research on wildlife crossings on US 93 in Montana, and a cost-benefit analysis study that documented the direct and indirect costs of collisions with large animals.
The Jackson Hole News and Guide has published “Bridging a future for wildlife,” a feature article on proposed wildlife crossings structures for Wyoming highways. In the article, WTI Road Ecology Program Manager Rob Ament discusses how crossing structures can be highly effective in reducing collisions between vehicles and large mammals, especially if the locations are carefully sited and the structures are designed to meet the needs of the target species. WTI has conducted wildlife mitigation planning in Wyoming; Marcel Huijser, Rob Ament and the rest of the Road Ecology team collaborated on the development of the Teton County Wildlife Crossings Master Plan, completed in 2018.
WTI is conducting a research on behalf of the Wyoming Game and Fish Department (WGFD) and the Wyoming Department of Transportation (WYDOT) to explore mitigation options for reducing wildlife vehicle collisions along Interstate 25 in central Wyoming. WYDOT and WGFD would like to explore the possibility of funneling large mammals, particularly mule deer and pronghorn, through the existing underpasses on this section of road rather than building new ones specifically designed for wildlife.
As one of the research steps, project researchers Marcel Huijser, Amanda Warren, and Elizabeth Fairbank collected preliminary data on wildlife use of existing structures under I-25 which were not originally designed for wildlife. Based on an eight-month monitoring effort in 2018-2019, the research team found that the structures are predominantly used by mule deer and white-tailed deer, but almost never by pronghorn. More details are available in the interim report (“Preliminary Data on Wildlife Use of Existing Structures along I-25, Kaycee, Wyoming, USA”), which was recently published and is available on the project page of the WTI website.
While wildlife fencing and crossing structures have been shown to reduce the effect of roads on medium and large animals, less is known about how these structures affect the movements of small mammals. The Canadian Journal of Zoology has published “Factors affecting the permeability of road mitigation measures to the movement of small mammals,” an article by Adam Ford and WTI Research Scientist Tony Clevenger, based on research they conducted on four small mammal species along the Trans-Canada Highway Corridor in Banff National Park. The article includes recommendations for culvert design and maintenance to promote usage of these structures by small mammal species to cross highways.
Citation: Ford, Adam T. and Clevenger, Anthony P. Factors affecting the permeability of road mitigation measures to the movement of small mammals. Canadian Journal of Zoology, 2019, 97(4): 379-384, https://doi.org/10.1139/cjz-2018-0165
The business website Quartz (www.qz.com) has published a feature article on the international use of wildlife crossing structures. “Wildlife overpasses that protect animals are spreading globally” discusses WTI Road Ecologist Tony Clevenger’s findings on the types of crossings preferred by different species of animals, based on his research on the Trans-Canada Highway. It also mentions Road Ecology Program Manager Rob Ament’s efforts to help countries like Bhutan to start using wildlife crossings to protect species like Asian elephants.