Wildlife migrations are here, placing both animals and drivers more often in precarious positions on the road. A new report by The Nature Conservancy of Wyoming seeks to shed light on the subject, …
Wildlife migrations are here, placing both animals and drivers more often in precarious positions on the road. A new report by The Nature Conservancy of Wyoming seeks to shed light on the subject, pointing out the state’s abysmal statistics.
The annual number of wildlife–vehicle collisions reported continues to rise, with a current five-year average of 7,656 animals killed on the highway per year. The vast majority of these collisions (approximately 5,500) involve mule deer, which are already in decline.
“Collisions often result in costly vehicle damage and can lead to human injuries and death. They are almost always fatal for the animals,” said Dr. Corinna Riginos, director of science at The Nature Conservancy in Wyoming, in the report. “At the current rate, there are 21 big-game collisions every day in Wyoming, eight of which involve significant damage to vehicles and/or human injury.”
Deer–vehicle collisions averaged 6,651 per year, or about 87% of total accidents, with approximately 5,500 of these involving mule deer. Pronghorn collisions averaged 593 per year, elk collisions averaged 253 per year and moose collisions averaged 69 per year.
“At this rate, we are losing about 1.5% of Wyoming’s mule deer population per year in wildlife–vehicle collisions. Since the reported numbers are a substantial under-count, we may really be losing 3% or more of Wyoming’s mule deer population per year in these collisions,” the report noted.
Over the last 15 years, the numbers have doubled and are expected to double again by 2035 if the problem isn’t addressed. What’s more, the actual number of accidents and animal deaths is “probably twice the number that get counted,” the report states, because not all collisions are reported.
Wildlife vehicle collisions are a pricey problem. The cost of these accidents in Wyoming averages about $55 million per year. The report assembles current and long-term data on wildlife-vehicle collisions, roadway hotspots for these accidents and makes recommendations on ways to help reduce them.
“Here in Wyoming, we pride ourselves on our great herds of mule deer, pronghorn, elk and other big game,” Riginos said. “These animals are part of the livelihood, culture, and economy of the state. When these herds interact with our roads, however, the result is often dangerous for the animals and the traveling public.”
The study is designed as an effort to “bring partners and stakeholders up to date on the current numbers, trends, and maps to assist in communicating and raising funding and public awareness about the topic of roads and wildlife.”
The report focuses on big game, primarily deer, pronghorn, elk and moose, both “because of the ecological importance of these species in Wyoming and because we lack data on the impacts of roads on most other groups of animals,” the report says.
“This is not to diminish the fact that roads often have a profound impact on a wider array of wildlife, including large and small carnivores, fish and fish passage, raptors, sage-grouse, reptiles and amphibians, small mammals, insects and more,” it stated.
Addressing the effects of roads on these other species is beyond the scope of The Nature Conservancy report. However, it suggests any decisions about roads and wildlife should take into consideration potential impacts not just for big game, but also for other groups of animals.
The wildlife–vehicle collision data comes from two databases maintained by WYDOT. The Nature Conservancy’s report follows a 2016 publication by the Wyoming Department of Transportation and Federal Highways Administration that assembled similar data on collisions from 2008-2013. Yet, in the past decade since WYDOT’s report, wildlife vehicle collisions have continued to increase.
The department’s animal–vehicle crash data is collected when an animal collision is reported to highway patrol because there was significant damage to the vehicle (typically reported if in excess of $1,000) and/or human injury. WYDOT’s roadside carcass count data is collected by highway maintenance crews. While crash data is more precise in terms of recording the time and location of the collision, there are many collisions that do not involve damages and do not get counted in the crash database but nevertheless result in an ungulate mortality and are counted in the carcass data.
U.S. Highway 14A between Powell and Cody has one of the highest reported wildlife/vehicle accident rates in the state. Wyo. Highway 120 near Meeteetse and U.S. Highway 20 near Worland and Thermopolis also rank near the top of nearly 16 accidents per mile.
Riginos believes there’s room for improvement.
“There are real solutions to these challenges, and we have made great progress in advancing them over the last few years. We have a unique opportunity ahead of us to make an even greater difference in the coming years, by leveraging Federal infrastructure dollars. With motivation and collaboration, we can make Wyoming’s roads safer for wildlife and people alike.”
The report calls out recent successes — including locations where changes have reduced the number of collisions — as well as offering suggestions motorists may find helpful in advancing solutions that reduce the accidents.
For more information visit nature.org/content/dam/tnc/nature/en/documents/wyoming-impacts-of-roads-on-wildlife.pdf