Incorporating climatic considerations into wildlife crossing planning is essential for the future
Written by Caitlin Littlefield & Julia Kintsch
May 29th 2025
Photo credit: Jerry Neal, Colorado Parks & Wildlife
A crucial, but underappreciated, climate adaptation tool
The benefits of wildlife crossing structures—such as culverts, underpasses, overpasses, and associated fencing—are substantial and well documented across the globe. Benefits include reducing accidents and wildlife mortality, mitigating population fragmentation, protecting access to breeding grounds, and more. And yet there is another important benefit that is often underappreciated: the potential to support wildlife in adapting to climate change. As effective as wildlife crossings can be, their siting and design too often fail to account for climatic changes and impacts, and there remains considerable opportunity for a more holistic integration of landscape-scale, climate-adaptive considerations in planning.
Planning for the future
We recently published a paper that explores this critically important topic. First, we synthesized the science surrounding wildlife crossings and climate adaptation in a comprehensive literature review and, then we demonstrated an approach for incorporating climate considerations into transportation project planning through a case study in southwestern Colorado, USA.
Figure 1. Change in elk connectivity during migration between present day and future timepoints across the study area in southwestern Colorado. Connectivity along a section of Highway 160 (box in a) is shown under present (b) and future (c) conditions. Circles represent potential crossing locations identified in the Western Slope Wildlife Prioritization Study, with filled circles denoting those locations ranking in the top ten for highest connectivity value under present (pink) or future (yellow) conditions or in both present and future (turquoise).
The case study aims to empirically prioritize potential wildlife crossing locations to explicitly account for how climate change may shift wildlife movements—in this case, elk migration. We used data on the movement of elk from GPS collars that were collected by a local tribe in a series of models (habitat selection, movement, and connectivity models) to map where elk migration routes are likely to shift and intersect with roadways in the future by accounting for projected changes in temperature, precipitation, vegetation cover, land-use, and traffic. These models revealed which locations were most likely to support elk movement and reduce wildlife-vehicle conflict both today and in a warmer future.
The locations that support both movement under current conditions and predicted climate-driven movement suggest possible targets for initial climate-informed wildlife crossing investments, as they are most likely to offer the greatest benefits now and into the future (Fig. 1). We recently leveraged this analytical approach into an effort with the Nevada Department of Transportation and the Nevada Department of Wildlife to inform statewide wildlife crossing priorities.
Recommendations for implementing climate-informed wildlife crossings
Successfully translating this sort of applied science into practice requires several key considerations that our paper discusses and that are described in more depth in this set of expert-informed recommendations:
Planning for the long-term at the landscape-scale. Establishing incentives and clear methodologies for incorporating wildlife movement into short- and long-term transportation planning and resiliency programs, such as flood-resistant culvert replacements (Fig. 2), provides cost-effective, win-win solutions for both wildlife and motorists while enhancing infrastructure resilience.
Promoting equitable engagement, cross-jurisdictional coordination, and interdisciplinary expertise. Greater engagement with tribal nations and historically marginalized communities and coordination across jurisdictions and agencies helps support the exchange of data and resources, integration, and ensure mutual accountability and buy-in.
Stimulate innovation and actionable science. Funding mechanisms should reward strategic innovation in less carbon-intensive materials and construction and in novel designs likely to be durable under changing conditions. Emphasizing societal cost-savings from climate-informed wildlife crossings—and, conversely, the costs of inaction—can fast-track their adoption. Finally, sustained support for accessible, actionable science and boundary-spanning initiatives will be important for ensuring incorporation of the best available science in wildlife crossing decision-making.
Figure 2. A bottomless culvert over a brook in Massachusetts that replaced a flat-bottomed culvert perched above the water, inhibiting fish and amphibian passage (Photo credit: Massachusetts Division of Ecological Restoration).
Navigating uncertainty
Even as the science advances, uncertainties remain: Precisely where and when will wildlife species move under changing climatic conditions? Where will humans move, with implications for transportation infrastructure and traffic? How can investments in wildlife crossing structures simultaneously accommodate the needs of numerous and diverse wildlife species? The persistence of these unresolved questions does not mean we must forestall action. Rather, ample scientific evidence shows that wildlife crossing infrastructure can provide myriad climate-adaptive benefits to wildlife and ecosystems while improving human safety. Such climate-informed wildlife crossings likely represent one of the most cost-effective, tangible solutions for jointly protecting wildlife, ensuring driver safety, and enhancing the resilience of infrastructure and ecosystems in our interconnected and rapidly changing world.
Author information
Caitlin Littlefield, Conservation Science Partners (caitlin@csp-inc.org). Caitlin is an applied ecologist who works closely with natural resource managers and conservation practitioners across the USA to generate actionable climate adaptation science--from mapping where wildlife species will likely shift in response to climatic changes to building decision-support tools to inform post-fire forest restoration. She lives in the northern forests of Vermont, USA where she enjoys skiing, biking, and foraging.
Julia Kintsch, ECO-resolutions (julia@eco-resolutions.com). Julia is an ecologist specializing in wildlife corridors and mitigating the impacts of transportation on wildlife. In 2009, she founded ECO-resolutions and works on wildlife crossing planning, design, and research projects across North America. Her efforts have advanced the practice of transportation ecology and spurred greater collaboration among diverse public and private partners.
Source citation
Littlefield, C.E., Suraci, J.P., Kintsch, J., Callahan, R., Cramer, P., Cross, M.S., Dickson, B.G., Duncan, L.A., Fisher, J.R., Freeman, P.T. and Seidler, R., Wearn, A., Andrews, K.M., Brocki, M., Dodd, N., Gagnon, J., Johnson, A., Krosby, M., Skroch, M., and R. Sutherland. 2024. Evaluating and elevating the role of wildlife road crossings in climate adaptation. Frontiers in Ecology and the Environment. https://doi.org/10.1002/fee.2816
Editor:
Yun Wang
Cite this summary:
Littlefield, C. (2025). Incorporating climatic considerations into wildlife crossing planning is essential for the future . Edited by Wang, Yun. TransportEcology.info, Accessed at: https://transportecology.info/research/future-wildlife-crossings