Our Wild Lives · The Wildlife Society

Bridging the Gap: Transportation Ecology

·53 min·3 clips
Renee ties the funding barrier to a $350 million Wildlife Crossings Pilot Program.
1. Our Wild Lives frames Bridging the Gap: Transportation Ecology around a white-tailed deer collision on a back road and a conversation about roads and wildlife. 2. Dr. Patty Kramer, a longtime TWS member and consulting wildlife ecologist, and Renee Callahan, executive director of ARC Solutions, anchor the discussion because they cover the science and policy sides of wildlife crossings. 3. The episode asks how roads and highways can reduce wildlife-vehicle collisions while keeping habitat connected for mule deer, elk, pronghorn, salamanders, and Florida panthers. 4. Patty traces the history back to 1920s wildlife-kill records by the Stoners and to the interstate buildout that pushed Utah, Colorado, and Wyoming to add underpasses and overpasses. 5. She says North America's first overpass appeared in Utah in 1975, while Florida built 27 wildlife crossing structures on the highway across Alligator Alley to accommodate water, panthers, alligators, and birds. 6. Patty says digital motion-triggered cameras in the early 2000s finally let researchers show DOTs that crossings work, replacing track counts alone. 7. She describes learning to work with engineers and politicians in Gainesville, Florida, where her group pushed Florida DOT to add crossings across Payne's Prairie plus a one-foot concrete wall for amphibians and reptiles. 8. Renee explains that ARC Solutions grew out of the world's first international wildlife crossing infrastructure design competition, with a winner announced at the 2010 Transportation Research Board Annual Meeting in Washington, D.C. 9. She says a 2012 survey of more than 500 SDOT and state DOT officials found funding to be the number-one barrier, with 68% naming it the main obstacle to building wildlife crossings. 10. That funding problem led to policy work that helped secure $350 million for the Wildlife Crossings Pilot Program in the 2021 infrastructure law. 11. The same law also pushed Federal Highways to develop standardized methods for collecting and reporting crashes and carcasses, which Patty says researchers have wanted for decades. 12. Patty distinguishes wildlife-vehicle collisions from crossing structures: crash data shows only reported hits, while carcass data and habitat data reveal where animals actually need to move. 13. She gives examples from Amherst, Massachusetts salamander pipes to small culverts for snakes and medium-sized mammals, and she warns that long, dark tunnels over 200 feet can repel animals. 14. White-tailed deer, mule deer, elk, pronghorn, and bighorn sheep each use crossings differently, with pronghorn and elk often preferring open overpasses and mule deer avoiding long, enclosed underpasses. 15. Patty calls elk her problem child, saying they will pull down fences, jump escape ramps, and walk miles to find the end of a fence before adapting to a structure. 16. The conversation ties GPS collar data from Interstate 80 in Wyoming and roads near Flagstaff to a larger question about how highways block migratory routes and winter range. 17. Patty says the Sublette mule deer herd near the Utah-Idaho border lost herd memory of west-side resources after Interstate 15 cut through its route, and some animals now shoot south into Utah looking for food. 18. She adds that climate change and wildfires make crossings even more urgent, pointing to bighorn sheep on a Colorado overpass and mule deer on a Utah underpass moving past a fire backdrop. 19. Renee and Patty both stress that successful projects depend on long timelines, regular DOT-and-wildlife-agency meetings, pre-scoping, programming-stage planning, and private-land cooperation such as Idaho conservation easements near U.S. 30 south of Montpelier. 20. The tone is calm and technical, with Patty and Renee answering long, layered questions from the host. 21. Transportation planners, wildlife biologists, and DOT policy staff will get the most value. 22. Listeners wanting a light nature story can skip it.

As heard by us

A clear look at wildlife crossings, road impacts, and the case for steady funding.

The episode takes on transportation ecology with a clear focus on how roads break habitat continuity and shape wildlife movement. It is most persuasive when it moves from the human cost of road mortality into the science of crossings, including why some passages work for one…

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If you want to hear how a highway becomes a habitat problem, start here.

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