By Mike Koshmrl

A dozen or so wild horse advocates and photographers were gathered on a ridgeline near White Mountain in August 2024 when news started spreading that federal land managers got the OK from the courts to eliminate two entire herds, and a part of another, from 2.1 million acres of the area known as the Red Desert. Cheyenne resident and amateur photographer Robyn Smith was immediately bummed. “Argh, oh crap,” she said. “That’s a lot of horses.” More than 3,000 horses, US District Court of Wyoming Judge Kelly Rankin had ruled, could go.  

The group of activists were gathered to oversee an unrelated horse roundup in the so-called checkerboard region of southwest Wyoming, a 40-mile-wide swath of land where one-square-mile blocks of private and Bureau of Land Management (BLM) property meet at the corners. Fences are few in the region, so thousands of horses pass on and off the private land daily. These walkabouts, and the underlying land ownership pattern, have proven a land management quagmire that has been the source of a half century of conflict, despite sporadic coordination.  

Rankin’s ruling in favor of horse removal was just the latest development in the debate over whether and how many mustangs should be allowed to roam the checkerboard. The back and forth involves woolgrowers and cattle ranchers who don’t want the free-roaming horses on their private land, the BLM, an agency that’s required by the Wild Free-Roaming Horses and Burros Act to maintain them on the federal property, and wild horse advocates, who want to protect the animals and health of the herds.  

Some 14 months later, however, the herds slated for elimination were still there. They’d even grown larger. The reason is litigation, which has dominated the 54 years since horses in the Red Desert became federally protected. As herd sizes continuously exceed goals, frustrations have grown. But middle-ground solutions have failed to gain traction as the camps in the checkerboard horse dispute have become gridlocked, leaving today’s land managers and horses at an impasse. 

Before 1971, when the Wild and Free-Roaming Horses and Burros Act passed, ranchers in the checkerboard who run cattle and sheep as a collective under the Rock Springs Grazing Association took wild horse management into their own hands. “They removed excess numbers, and at that time they went to slaughter, for the most part,” says Christi Chapman, who’s a longtime wild horse advocate: She co-founded the all-volunteer Wyoming Wild Horse Improvement Partnership. “They did a good job, because they cared about the land and they wanted to have enough room for their livestock. But they liked the horses—they didn’t want to see them go completely away.”  

After the Wild Horse Act passed, management shifted to federal officials. The law protects free-roaming horses from “capture, branding, harassment, or death,” prohibits commercial sale for slaughter, and declares them “living symbols of the historic and pioneer spirit of the West.” It passed both chambers of Congress unanimously and was shepherded by the matriarch of wild horse advocacy, Velma Johnston, who was known as Wild Horse Annie.  

At that time, wild horses and burros roamed free on roughly 54 million acres of federal land, mostly BLM property. The new federal law didn’t demand blanket protections for equines everywhere. Land managers inventoried the West, looking at factors like vegetation and water, and ultimately defined 179 “herd management areas” covering nearly 32 million acres in 10 states where the landscape was considered able to sustainably support horses. In another 20-million-plus inhabited acres, free-roaming horses weren’t thought of as practical long-term residents because of habitat constraints or resource scarcity—these were labeled “herd areas” and are not managed for horses. In southwest Wyoming’s Red Desert and Green River Basin, nine HMAs were established, some of which included hundreds of square miles of the checkerboard.  

A key provision of the Wild Horses and Burros Act instructs agencies to “remove stray wild horses from private lands as soon as practicable” when asked by a landowner, who are prohibited from removing or destroying horses on their own. That made the broad swath of interchanging public and private land that forms the checkerboard tricky, and negotiations essential. Shortly after it passed, members of the Rock Springs Grazing Association met with Johnston and the BLM to discuss management for horse herds in the region. In the new era, the association had plenty of incentive to work with the BLM to keep horse numbers in check. Their livestock depended on the same rangeland and would have to compete for forage with the free-roaming horses, which can reach 1,000 pounds and face little predation. “They had a great conversation,” Chapman says. They even came to terms on population targets.  

But the horses thrived and the herds grew in the absence of rancher management—unchecked, herds can swell by 20 percent annually. The association’s ranchers tried to get the BLM to step in with large roundups to no avail, and by the late 1970s they sued. A negotiated legal settlement came out of it, and that deal was for four herds totaling no more than 1,600 animals in the Red Desert region. “BLM-Wyoming complied without delay, but it took from 1980 to 1985 to reduce the number of horses from almost 7,000 to 1,600,” Rock Springs Grazing Association Manager Don Schramm testified to Wyoming lawmakers in 2023. The herds had sprawled across the landscape and gathering them was difficult and costly—as was finding a home for them, because the free-roaming animals could no longer be killed.  

Horse populations fluctuated in the two decades that followed. Roundups would drive numbers down to near the 1,600-animal target, but then years would go by. “They would double by the time of the next roundup,” Schramm said in his testimony. “We did our best. We had the support of the state, BLM, wild horse interest groups, the Washington office employees, administrative officers and RSGA. It was a team effort.” But it wasn’t enough, and the wild horses spent far more time above the agreed-upon population limits than near or below the threshold.  

“I will say this: I feel like it’s not the BLM’s fault,” Chapman says. She pinpointed two reasons, naming constant litigation and a lack of resources for federal land managers to carry out their horse-removal duties. Wild horse management has proven to be an extraordinary drain on BLM coffers. Roundups, which rely on helicopters and big teams of wranglers, are pricey, but most of the expense goes toward paying for the horses to live out their days. Some rounded-up mustangs are adopted and domesticated, but most end up in long-term corrals and in off-range pastures where board, feed, and veterinary bills cost more than $100 million annually.  

Finally, in 2010, frustrated ranchers revoked their consent to tolerate horses on private land in the checkerboard, asking that the herds be removed entirely. The BLM went along, citing the act, and even sought to remove herds from the public land squares interspersed throughout the checkerboard. This would have been an almost unprecedented move. While roundups eliminating horses from the “herd areas” are somewhat routine, the designated herds have remarkable staying power. 

“BLM has only zeroed out a herd two times in history,” says Bill Eubanks, an attorney who has represented horse advocacy plaintiffs in the Red Desert dispute for over a decade. The Colorado and Nevada herds that were eliminated faced dire straits from a landscape that lacked enough resources for their survival. Animals were “emaciated,” Eubanks says, and federal law explicitly permits removing herds “in order to preserve and maintain a thriving natural ecological balance” in areas. “The agency ultimately documented that they could not keep a genetically viable, self-sustaining wild horse herd,” Eubanks says, “because it was just impossible.”  

The rationale for getting rid of the Red Desert herds was starkly different. It hinged on the RSGA asserting its rights to have stray wild horses removed from private lands as soon as possible, and the assumption that herd elimination was the only reasonable way to do that in the checkerboard.  

The association sued BLM again three years later, and out of it came another settlement agreement. This one called for eliminating two herds and shrinking two others. Wild horse advocacy groups, represented by Eubanks, got involved with their own lawsuit, arguing violations of the Wild Horse Act, National Environmental Policy Act and other federal laws. After a federal district court defeat, the horse advocates prevailed when the 10th Circuit Court of Appeals ruled in 2016 that the federal agency broke the law by treating the entire checkerboard as if it were private property.  

Appellate Judge Monroe McKay and the court acknowledged the “practical realities of the checkerboard” and the need for BLM to find a “workable solution,” but still faulted the agency for ignoring a key provision of the act. “It seems to me that the only way the BLM can ultimately lawfully achieve its [ecological balance] duty to maintain wild herds and prevent destruction of viability caused by over grazing on public lands is to go back to step one and make appropriate judgments by redetermining the HMAs without the non-permissive use of private lands,” McKay wrote.  

While the BLM went back to the drawing board, the herds kept steadily growing. In the winter of 2022–2023, the federal agency commissioned an infrared aerial survey that found roughly 4,700 horses in the Red Desert herds. Roundups followed and a similar assessment at the end of 2024 found just shy of 3,700 animals.  

Around the West, the pace of roundups has long been inadequate to keep up with population growth, in some areas resulting in ecological harm rather than ecological balance. As of spring 2025, the number of free-roaming horses and burros nationwide was approaching 75,000—nearly triple the BLM’s targeted numbers. Nevada, which hosts nearly half of them, has been the poster child of feral horse overpopulation run amok, and its state biologists have reported that the equines eat more forage than all the native ungulate species, like elk and mule deer, combined.  

Impacts to wildlife have also been documented in Wyoming. A University of Wyoming-led research team examined how free-roaming horses influence sage grouse and found evidence that overpopulated Red Desert herds are hurting the imperiled birds’ survival rates by breaking up sagebrush, increasing bare ground and denuding watering holes. Wildlife managers on the Wind River Indian Reservation—which isn’t subject to the Wild Free-Roaming Horses and Burros Act—reported dramatic, almost overnight changes after rounding up nearly 8,000 horses in 2022 and 2023. “It was at an ecological crisis point,” US Fish and Wildlife Service Supervisory Biologist Pat Hnilicka said at the time. “If something wasn’t done, there was no turning back.”  

In the Red Desert, near where her family ranches, Chapman has seen feral horses eat themselves out of a home during periods of drought and succumb to severe winters. It was especially hard to watch, she says, during the winter of 2022–2023. “We found families of horses dead within feet of each other,” Chapman says. “It was just really sad.” 

Wild horse enthusiasts, however, contend that equines are being unfairly scapegoated when it comes to impacts on the land. Casper College instructor Chad Hanson, who’s an avid horse photographer and writer, says that their impacts on grasslands are “red herrings”—arguments intended to distract from more significant concerns. “The BLM’s rangeland assessments make it clear: Livestock represent the most significant threat to the health and vitality of our public lands,” says Hanson, who joined the checkerboard horse lawsuit as a plaintiff.  

But there is a distinction between how horse and livestock impacts to rangeland are handled, according to Jim Magagna, a longtime lobbyist for the Wyoming Stock Growers Association. “It’s the only major species of animals out there that isn’t managed,” he says of Red Desert horses. “We manage our livestock—we harvest our calves and lambs every fall. We manage our wildlife through hunting seasons.” Because wild horses, legally, are neither livestock nor wildlife, the BLM’s toolkit for managing them is much more constrained.  

Attempting to remedy the court’s concerns after the 2016 loss, federal authorities prepared an environmental impact statement and updated its resource management plans for the Rock Springs and Rawlins areas.  “We’ve been trying to come up with a solution,” says Brad Purdy, a senior advisor for the BLM’s Wyoming office. The federal agency’s analysis assessed different scenarios, in part demonstrating “adequate forage, water, cover and space” to support horses if the trimmed-down herds were confined to solid-block public land outside the checkerboard. Still, there were concerns the herds would easily drift back onto private land.  

Ideas for solutions included fencing the checkerboard and keeping horses on public ground, but that would require extensive fencing that would bisect big game migration routes and could even harm sage grouse prone to striking them. It was called “not technically feasible” and the gargantuan task was dismissed. 

The assessment also considered and dismissed a land swap to consolidate private and public property. “For a land exchange, you’ve got to have a willing partner—and I don’t think we had a willing partner,” says Purdy, the BLM-Wyoming senior advisor. “I’m not saying that in a negative way. It’s completely up to private landowners whether they want to engage in a land exchange with the Bureau of Land Management.”  

The option the agency ultimately landed on was to get rid of the Great Divide Basin and Salt Wells Creek herds, which dwell in areas that are respectively 48 percent and 72 percent checkerboard. The northwestern portion of the Adobe Town Herd, an area that’s 42 percent checkerboard, would also be lopped off and managed for zero horses. In total, the contested plans called for ridding roughly 2.1 million acres—an area about the size of Yellowstone National Park—of more than 3,000 free-roaming horses. “When you weighed it all out, this was the most informed and the best decision, I think, the BLM could have made,” Purdy says.  

Initially, the courts were on board, upholding the agency’s plans. Rankin’s August 2024 opinion—the ruling that bummed out Smith and the other roundup observers—recognized the BLM’s bind of having to remove the private land horses and having no practical means of keeping others on checkerboarded public land. Repped by Eubanks, horse advocacy groups and individuals again appealed to the 10th Circuit Court of Appeals.  

By spring 2025, BLM was already setting in motion its renewed plans, but history repeated itself, and again the 10th Circuit put a stop to the roundups. Like nearly a decade prior, the court faulted BLM for not demonstrating how removing all horses from public land in the checkerboard is necessary to achieve a “thriving natural ecological balance”—language from the Wild Free-Roaming Horses and Burros Act. “They said it’s the guiding principle of the act, as Congress wrote it, and you can’t just ignore that,” Eubanks says.  

Federal officials turned heads by announcing they were proceeding with the elimination roundups despite the appeals court ruling, sparking another lawsuit, then another—and eventually an assurance that nothing would happen before summer 2026. 

So several thousand Red Desert horses remain on the landscape, and land managers, stockgrowers and horse advocates are at a stalemate. “This whole controversy, it’s been a standoff for 15 years,” Chapman says. “I’ve been here since day one, right in the middle of it.” The 10th Circuit’s summer 2025 opinion instructed BLM to go back to federal district court to resolve concerns about “ecological balance,” but BLM’s earlier plans stated there was no ecological justification for removing the Red Desert herds. There was no scarcity of forage, water, cover and space, according to its own analysis.  

Pro-horse plaintiffs say the stakes are high. Herds around the West could be at risk if BLM prevails in removing whole herds because of the checkerboard’s private land, Eubanks says. Every herd management area in the country contains private inholdings or non-federal land. “Where do you draw the line?” the attorney says. “There’s not really any coherent reason why it could not apply elsewhere. Does BLM see this [argument] as specific to these herds, or is this really something that they’re testing out? We don’t know.”  

Meanwhile, ranchers’ patience has been exhausted after decades of legal disputes and the BLM failing to achieve targeted numbers. Magagna, at the Wyoming Stock Growers Association, sees few prospects for coexisting with free-roaming horses in the long-term. “At this point, the only way that the landowners could be satisfied outside of a total removal would be if they were reduced down to [agreed-upon] numbers, with a firm guarantee that the horses would be held at those numbers,” he says.  

Others say the potential solution was prematurely dismissed by the BLM. “I think the right solution is for the federal government to have land swaps with the checkerboard landowners and consolidate the private lands and the public lands,” says Erik Molvar, a biologist who directs the Western Watershed Project, an environmental group that focuses on negative impacts of livestock grazing. “Once you consolidate the private lands, then under the Wild Horse and Burro Act, the wild horses that stray can be removed back onto the public lands—and the private landowners can have wild-horse-free private lands.”  

As long as a decade ago, Eubanks was encouraging BLM to consider a land swap as a mutually palatable solution so that the Rock Springs Grazing Association would be unencumbered by horses, which would then dwell only on solid-block public lands. “Not one time has BLM even explored the idea—they just refuse to even consider whether it’s a viable option,” Eubanks says. “What’s especially peculiar is BLM does land exchanges of substantial size. They’re the agency that specializes in these federal/non-federal land swaps for precisely this type of purpose.”  

For now, the steady stream of litigation is keeping the Red Desert horse dispute in flux. As this story was going to press, the federal agency and Rock Springs Grazing Association had not shown their hand, declining interviews about legal next steps to satisfy the court’s concerns about “ecological balance.”  

“They could interpret the 10th Circuit opinion differently than I do,” says Eubanks. “We have very little intel on how they’re going to approach these issues. It may be that the outcome of their evaluation sparks more litigation. I’m sure that would be a surprise to no one.” 

This story was created in partnership with WyoFile, an independent nonprofit news organization that covers Wyoming. 

Mike Koshmrl is a Lander-based journalist who reports on wildlife and natural resource issues for WyoFile. 

Header image: Research in Wyoming has indicated that wild horses may threaten sage grouse survival rates by breaking up sagebrush, increasing bare ground, and denuding watering holes. Wild horse enthusiasts counter that horses are being unfairly scapegoated for environmental degradation, laying the blame on livestock instead. (Allegra Keenoo and Jacqueline Alderman/Bureau of Land Management)

By Amber Furness

I stand on a large, cement bridge on Interstate 355 over the Des Plaines River Valley in northern Illinois. Waves of air blow over me as vehicles whiz by. Then I see them—the iridescent green eyes—an endangered Hine’s emerald dragonfly flies towards me and then turns back, its wings shimmering in the morning sun. 

This was one of a multitude of observations I made of dragonflies over the course of three summers as a graduate student seeking to understand the influence of roadway construction and vehicle speed on the behavior, mortality, and conservation of adult dragonflies, especially the Hine’s emerald. I undertook three research projects to explore strategies for mitigating vehicle collisions for this endangered species. Numerous studies have looked into the negative impacts of roadways on wildlife, but the majority focus on vertebrates, especially mammals. Invertebrates make up a large percentage of road-killed wildlife; however, little is understood about these deaths, and still less is being done to mitigate them. 

My goal was to better understand road impacts to dragonflies and the relationship between vehicle speed and mortality to produce findings that could guide conservationists and highway managers. Invertebrate mortalities tend to be ignored, but that doesn’t mean that understanding them is any less important to the road ecology narrative.

I was already interested in threatened and endangered species recovery when I learned of the opportunity to earn a master of science in biology while researching an endangered dragonfly. The Hine’s emerald is medium-sized—about 2.5 inches long with a wingspan up to about 3.3 inches—and has emerald-green eyes, a metallic-green body, and cream-yellow stripes on its thorax. It lives in spring-fed wetlands and sedge meadows overlaying dolomitic bedrock in Illinois, Wisconsin, Michigan, and Missouri. Habitat degradation and loss is the primary threat to this species that historically lived in Alabama, Indiana, and Ohio as well. Its larval habitat is incredibly difficult, if not impossible, to re-create. Thus, it has been a priority to focus on other ways to protect the species, including from the influences of roadways. This led to my projects researching how the Hine’s emerald dragonfly responds to bridge construction, vehicle speeds, and diversion netting to help conserve this rare species.

To investigate how bridge construction influences dragonfly flight behavior, I spent the summers of 2011–13 observing dragonflies on and below the I-355 bridge in northern Illinois. My research lab initiated the study before the bridge’s construction began in 2006 and followed it through 2007 as the bridge was completed and then for six more years after the bridge opened. This 1.3-mile long, six-lane bridge was designed with 80 feet of clearance below the deck to minimize its impact on wetland areas it passes over which includes Hine’s emerald dragonfly habitat. The idea was that with such high clearance, the adult Hine’s emerald would surely fly under, rather than over the bridge, thereby avoiding interaction with traffic altogether. My goal was to put all the data together to evaluate whether or not the bridge was hindering movement of Hine’s emeralds. 

Standing under the bridge and on the bridge deck (with one lane closed), lab members recorded when approaching dragonflies flew under, over, or away from the bridge. We found that the Hine’s emerald dragonfly initiated crossing significantly more often prior to the completion of the bridge than when the bridge was nearly complete in 2007 and for the six years of the study that the bridge carried traffic. This indicates that the bridge impedes movement of the species despite its height. In 2013, the last year of the study, of all dragonflies observed, 91 percent never attempted to cross the bridge. Of those that did, nearly all flew over rather than under the bridge, putting them at risk of colliding with vehicles. 

To determine how vehicle speed influences roadway mortality of dragonflies, we developed a study on roads in Door County, Wisconsin, during the late spring and summer of 2012 and 2013. We mounted GoPro cameras to the top of a truck, and I watched for dragonflies from the passenger seat while a driver drove 15, 25, 35, 45, and 55 miles per hour, mostly on a road known to pass through and along Hine’s emerald and other dragonfly habitat. When we encountered a dragonfly, I recorded the type of dragonfly, its flight height, and its fate. I relied on the many hours I’d spent observing dragonflies in flight to identify them, making judgements based on silhouette, size, color, wing markings, and flight pattern. When I wasn’t confident in my identification, I watched the videos captured by the GoPro cameras to assist me. On the occasion when we hit a dragonfly (17 times), we stopped to retrieve it and verify its identification. 

We did this for almost 1,500 miles over two flight seasons. In all, we encountered 262 dragonflies from 15 species. Of the 262 encounters, at least 83 were Hine’s emeralds or other species in the same genus as the Hine’s (Somatochlora). I discovered that straight-fliers, including the Hine’s emerald, are more vulnerable to dragonfly-vehicle collisions than those that fly in zig-zag/bobbing patterns. Additionally, simply reducing vehicle speed from 55 to 45 miles per hour lowered the probability that a dragonfly of any species would be hit from 28 percent to 11 percent. For species belonging to Somatochlora—like the Hine’s emerald dragonfly—the probability of being hit drops staggeringly from 65 percent down to 27 percent. 

As we thought about other methods to decrease the number of dragonfly carcasses along the roads, we wondered whether or not we could use netting to divert them from the road or force them to fly above traffic. A partner and I set up 3-meter-high diversion netting along the edges of two simulated roads, one 6 meters wide and one 12 meters wide, and then observed Hine’s emerald dragonfly flight heights and reactions to the netting. I wanted to know whether the Hine’s emerald would fly above the nets at either spacing, whether they would dip lower over the simulated road, or whether they would turn away from the nets, which would keep them out of traffic but also prevent them from moving between habitat patches. We found that the netting caused Hine’s emeralds to fly higher than when no nets were present, especially when the nets were only 6 meters apart. It also deterred some Hine’s emeralds from crossing the “road” at all. 

Because this was the first look at this idea, more work needs to be done before this method could be implemented. Results do suggest that this, or similar options, might be worth exploring further to keep dragonflies away from vehicles. 

Good science is crucial to helping us better understand the often-ignored impacts we have on other species. Even though these studies focused on a few specific areas in the Midwest and the dragonfly species found there, the findings and the methods we developed could have implications for mitigating the impacts of roads to dragonflies—and perhaps other invertebrates—in other parts of the United States and the world. At that time, two of these studies were the only of their kind, and the bridge study was only the second to document the effects of a bridge on insect flight behavior. 

We learned that building a super high bridge makes no difference, that erecting roadside netting might be a lower cost solution, and that slowing down by 10 miles per hour could have the greatest impact, probably at the lowest cost. Discovering the relationship between vehicle speed and the likelihood of a dragonfly-vehicle collision has power because it tells us what we can do. Conservation and highway managers could actually put this new understanding into practice and reduce one threat to an endangered species.

By Kristen Pope

Leather-clad motorcyclists cruised around Devils Tower National Monument in August 2015, eager to spot wildlife, breathe fresh air, and take in views of the towering monolith. While the riders were enjoying their public lands, scientists wanted to learn how noise from motorcycles was impacting local wildlife during the Sturgis Motorcycle Rally’s 75th anniversary. Researchers placed acoustic recorders in the park to monitor the impact of the “Devils Tower Run” August 5 event as well as the increased motorcycle traffic surrounding it. By placing recorders near the road as well as along a gravel road motorcycles couldn’t access, they established study and control sites to monitor bird and bat vocalizations. Camera traps and visual observations also recorded how other animals reacted to the increased noise levels.

Noise isn’t just annoying to animals—it disrupts some of their vital life functions. Chronic noise can make it difficult for animals to hear the cues they need for finding food, avoiding predators, communicating, and mating. Sudden, jarring noise can be perceived as a threat and cause animals to react by hiding, fleeing, or spending more time and energy on being vigilant rather than things like finding food. Especially loud noises can cause severe issues like hearing loss, but even if a species isn’t directly impacted by noise—or when the noise is outside a species’ hearing range—it can be affected indirectly, such as when a prey or predator species is impacted. Noise is considered a pollutant, and this is why researchers throughout the world are studying the impact roadway sounds have on ecosystems and wildlife.

In the Devils Tower study, researchers found animals had a variety of responses to the noise. Some, like the western wood-pewee—a small insect-eating bird—didn’t show much of a change in behavior. Others like white-tailed deer moved away from the road when it was loud but returned to their previous locations soon after the rally. Bats, on the other hand, showed a greater impact, with bat diversity reduced for weeks after the rally. The researchers noted that August is when mother bats and their pups emerge from maternity roosts, so they may be extra cautious during this time. Another theory is that the nocturnal creatures were especially sensitive to having their sleep interrupted, or perhaps the noise chased away bats’ prey insects and the bats followed. 

Rachel Buxton, a conservation biologist at Carleton University, was the first author on the Global Ecology and Conservation article about the study. “I think the important thing to note here, too, is that there’s a lot of activity in Devils Tower National Monument, and it’s a really small park,” Buxton says of the approximately 2-square-mile park. “So any animal that is remaining in the park has to be able to withstand a certain amount of noise anyways.” Animals in other, quieter areas may be more sensitive.

Of course, distinguishing sound from other road impacts can be challenging, so scientists created a “phantom road” to isolate these effects. Jesse Barber, sensory ecologist and associate professor at Boise State University, and colleagues worked in a roadless area to separate noise from other compounding effects. They set up an array of 15 pairs of speakers along a ridge crest in Idaho’s Boise Foothills, playing traffic recordings from a 45-mile-per-hour zone in Glacier National Park. For four days, they would gradually turn on the noise starting at 4:30 a.m. and gradually decrease the noise at the end of the day, turning the speakers off at 9 p.m. to mimic traffic cycles. Then, after four days of playing traffic sounds, they would silence the speakers for four days, before repeating the cycle.

The experiment was set during the fall bird migration, when almost all species stay in the area for fewer than eight days, allowing a new group of birds to be part of each experimental cycle. The Intermountain Bird Observatory has studied bird migration patterns in the area for over 20 years, so Barber knew birds’ typical patterns. Fall migration is a crucial time for the birds, when they must rest and conserve their energy for finding food and being vigilant.

“The cool thing about working in migration is that the birds are coming to you,” Barber says. “They’re passing through the site in waves.” 

The researchers found a 31 percent decline in bird abundance when the speakers were on, with some species almost completely avoiding the experimental area. To further study the influence of noise, the scientists captured and examined birds, finding 5 of the 21 species surveyed had “significantly decreased body condition index” when they were in the group of birds exposed to the noise, as reported in a PNAS article. They “were largely unable to gain weight, like a migratory bird should be able to do,” Barber says. “That’s their only job—to pack on fat and evade predators.” 

While Barber emphasizes they don’t know for sure, he says, “the effects that we found are really similar to what we see around real roads. That doesn’t necessarily mean that noise is the only thing causing trouble from roads, but it’s convincing experimental evidence that noise is a significant part of road ecology effects.”

Noise can also affect mating, as experiments have shown for some birds like ovenbirds and reed buntings. A 2013 literature review in Frontiers in Ecology, which Barber co-authored, noted that while ovenbirds don’t seem to leave when it’s noisy, “males defending noisy territories are less successful in attracting mates,” according to Habib et al, 2007. Reed buntings also have less success finding mates in noisy areas.

When more vigilant animals choose to leave an area to avoid noise, they leave the remaining animals—as well as themselves—more vulnerable since there is strength in groups. Further, when more risk-averse animals remove themselves, this could impact genetic diversity.

As scientists examine the impacts sound has on wildlife and ecology, they are also working to find solutions. Lower speed limits, instituting shuttle services in busy national parks, building berms along roadsides, and even a form of porous “quiet pavement” that absorbs traffic noise, could help. However, each option has limitations and trade-offs, from reducing habitat connectivity, to softer road surfaces requiring more frequent replacement. Barber points out it’s easier to solve the dilemma of road noise by avoiding building unnecessary roads in the first place. 

“Mitigating noise pollution from roads is not impossible, but it’s complicated, and I think that not building new roads is the number one conservation action,” Barber says. 

While scientists seek answers to reduce noise, they also point to the amazing natural soundscape found in nature and urge people to fully appreciate it. 

“Noise pollution is really negative but natural sounds are really quite amazing, and I think they’re often underappreciated,” Buxton says. “When you go to your local park or to a national park, natural sounds are just such an integral part of your experience. You think about the Grand Canyon and the beautiful expanse of the canyon but also you’re hearing the wind blowing through canyon, the sounds of the river, the sounds of wind going through the trees and birds singing, and that’s all part of your experience in a park and those are all natural resources that are really important…I really think that they’re deserving of our protection.”

Kristen Pope is a freelance writer and editor. Find more of her work at kepope.com. 

By Gregory Nickerson

When I drove across Wyoming’s stretch of Interstate 80 to film a wildlife documentary in fall 2019, I saw animals confronting the highway barrier again and again. At Dana Ridge in southeast Wyoming, I saw pronghorn making heavily tracked trails through snow. Constrained by fences and traffic, their hoofprints paralleled the interstate just outside the right-of-way fences for many miles. Near Sinclair, 18 miles further west, I saw carcasses where pronghorn had somehow made it through the interstate fence, only to collide with the traffic.

West of Little America, 150 miles farther on, I met Wyoming Game and Fish Department biologist supervisor Mark Zornes, who showed me the spot where one semi truck killed 25 pronghorn in 2017. The animals were trying to move south to better winter range near Flaming Gorge but got trapped and run over on a foggy morning. At the Leroy exit near the Utah border, I saw mule deer tracks going through an underpass that the Wyoming Department of Transportation (WYDOT) had retrofitted for wildlife. 

Thanks to GPS research, I can now fit all these wildlife anecdotes into the big picture of southern Wyoming’s landscape, where 400 miles of I-80 chop up habitat and obstruct movements that animals depend on for their survival. 

When the last major segment of I-80 in Wyoming officially opened for traffic more than fifty years ago on October 3, 1970, it bisected movement corridors for tens of thousands of big game animals. After eons of free-roaming life for these migratory herds, we’d plunked down a railroad, fences, and a superhighway through the middle of their home turf. 

For wildlife, I-80 is something like a Great Wall of China across the desert basins of southern Wyoming. The traffic volume of 5,000 to 13,000 vehicles per day makes the interstate virtually impenetrable to wildlife. On top of that, sections of the interstate are lined with eight-foot-tall exclusion fences to prevent wildlife-vehicle collisions. The barrier bisects many otherwise functional migration corridors, cutting off access to vast seasonal ranges and potential habitat, and limiting animals’ options to survive winter storms and summer droughts. 

Worldwide, human development and roads are pressing in and slicing across the habitats of migratory ungulates (hooved mammals). These ecological changes ultimately threaten migratory behavior and the survival of entire populations. One doesn’t have to look far, just to the Front Range of Colorado or the Wasatch Front in Utah, to see just how completely migration can be curtailed. These urbanized Rocky Mountain landscapes stand in contrast to Wyoming, where the naive first-time driver on I-80 may tell you there is nothing out there. Look closer though, and all that openness is punctuated with towns, the Union Pacific railroad, livestock fences, irrigated fields, subdivided private property, oil and gas wells, coal and trona mines, power plants, transmission lines, windmills, and solar farms. It’s a working landscape, busier than it has ever been.

And yet, moving through it all is still-abundant wildlife—likely more than you will see anywhere on I-80 from New York to San Francisco. Amid the islands of development in southern Wyoming, animals roam over wide swaths of relatively intact habitat. Places like the Great Divide Basin, which I-80 crosses in south-central Wyoming, are not so badly degraded that they can’t be returned to greater function. 

In the last 50 years, scientists tracking wildlife have moved from radio collars to sophisticated GPS mapping, revealing that the most severe fragmentation is due to the single, solvable barrier of I-80. Wyoming biologists and engineers generally agree that the time has come to address this problem and find new solutions for connectivity on I-80. The revolution in wildlife movement science is creating a vision for a reconnected landscape, one that bucks the global trend of habitat fragmentation, and restores free wildlife movement on a grand scale. 

Curtailed Movement

Construction of I-80 in Wyoming began in 1959, with much of the Red Desert segment from Rock Springs to Rawlins completed by October 1963. 

Signs of trouble for wildlife were already evident. As early as 1965, while construction was still ongoing, Wyoming Game and Fish Department biologist Bill Hepworth expressed concerns that I-80 and Interstate 25 would hamper pronghorn movements, because they generally do not jump over right-of-way fences like deer or elk. “Curtailed movement of some herds appears critical,” Hepworth wrote. By 1967, biologist Darwin Creek had assessed that I-80 traffic and fences had virtually stopped north and south movements of pronghorn in sections where the road was completed.

The new I-80 barrier combined with grazing allotment fences to create fatal consequences for migratory animals. In October 1971, a devastating blizzard roared across the interstate west of Rawlins, dropping 18 inches of snow. Huge numbers of pronghorn looking for areas with less snow succumbed to exhaustion at woven-wire fences and along I-80. Many were scavenged by coyotes, or completely buried by snow, such that biologists Phil Riddle and Chuck Oakley couldn’t make an accurate survey of the losses until the spring. Later aerial counts estimated that 3,111 pronghorn, or more than 60 percent of the Chain of Lakes population near Rawlins, had perished. While these deaths didn’t all happen along the interstate fence, they indicated a larger problem of lost connectivity for southern Wyoming pronghorn that rely on movement. Quite simply, when animals could no longer move freely to escape harsh conditions, they died.

At the request of the Wyoming Game and Fish Department, WYDOT built the Elk Mountain to Walcott Junction segment of I-80 with a number of underpasses for deer. On the western slope of Dana Ridge, workers built three box culverts and two machinery underpasses, but deer were very reluctant to use them. By 1976, six years after opening to traffic, some 725 animals had been killed on the 80 miles between Laramie and Walcott. The tally included 561 mule deer, 153 pronghorn, and 10 elk. The situation was bad enough that the Wyoming Game and Fish Department and WYDOT used funding from the Federal Highway Administration to solicit a study on how to reduce the mortalities and risks to motorists.

Lorin Ward at the US Forest Service Rocky Mountain Forest and Range Experiment Station led the research. In the winter of 1977-78, Ward tasked biologist Hank Henry with living in a trailer on the side of I-80 at the summit of Dana Ridge. It’s a spot where about 900 mule deer migrated through every spring and fall, some going as far as 50 miles from the Snowy Range to the Haystack Mountains along the Platte River. 

Henry was faced with the impossible task of trying to keep deer from doing an end-run around an eight-foot-tall exclusion fence designed to keep animals from getting hit on the highway. It was a long, lonely season, and sometimes he’d use roman candle firecrackers to scare deer away from the road. But the animals’ urge to migrate was too strong. Some mornings he’d wake up to find holes in the fence where deer had squeezed through. Other times the pavement was covered with a mix of glare ice and blood where deer had met their end.

Ward and his team eventually settled on extending the exclusion fencing to better keep animals off the highway, and direct them toward the underpasses. Within a few seasons, deer encouraged by fencing and apples as bait had learned to use the crossing structures, allowing nearly 1,000 safe deer crossings per year, and a 90 percent reduction in mortalities at that location. 

While pronghorn could not access the underpasses due to fences, and elk corridors were located elsewhere, about 400 deer still use these structures today. This was a major success story for deer, one that was repeated with underpasses at the “Sisters” area west of Fort Bridger. Yet, these were some of only a few wildlife crossing structures built in the state, and they only helped one species in a few specific areas.

Ward offered no suggested solution for pronghorn or elk crossings on I-80. “Since antelope are reluctant to jump fences and use underpasses, I-80 is a barrier and the herds are managed accordingly,” Ward wrote. “Since elk are large, they present a greater hazard to motorists, and should be discouraged from crossing highways by proper fencing and road location.” 

Reading this statement today, it seems that for Ward the primary motivations behind the Dana Ridge crossing structures were preventing wildlife mortalities and reducing risks to motorists. If pronghorn and elk didn’t cross the interstate, and deer could cross safely using underpasses, then the safety issue was largely resolved for WYDOT and the Federal Highway Administration. 

On the flip side, Ward seemed to imply that the wildlife connectivity problem was one for wildlife managers and biologists, who would have to accept the I-80 barrier as they pursued more wildlife tracking research. It remained difficult to assess the full scale of movements for the different species across 400 miles of highway, and how they had been curtailed. Biologists had only limited technology to understand or address the problem and wouldn’t get a more complete picture for several decades.

Biologists improvised tracking methods in creative ways, hoping to learn movement patterns and locations of summer and winter ranges that were affected by the interstate. Lorin Ward’s team placed blaze orange collars on three deer in hopes of spotting them later in a different spot, but the effort only defined the winter range for a single animal. 

Hepworth tried to mark pronghorn with ear tags, or with Nyanzol D black dye applied from an aircraft. He hoped for the development of a long-lasting fluorescent green or red dye that would be more visible. In lieu of that, Hepworth was sometimes able to document large movements by spotting a pronghorn buck with atypical horns in two distant places, but he wanted better methods. “A satisfactory means of marking large numbers of animals, preferably on an individual group or individual animal basis, is a must to aid in the study of migration and movement,” he wrote in 1965. 

Connectivity was also on his mind. “The effects of various barriers to antelope movement, particularly barriers to the critical movement to winter or summer range and water, are of primary concern at present.… Much work needs to be done to find fences and/or devices to allow movement,” Hepworth wrote, but, he lamented, “investigations into the basic ecology of antelope are still lacking.”

Wildlife managers knew there was more to the story, but they would need better tools to fill in the picture of how much I-80 was altering wildlife movements. It would take half a century for the technology to catch up and make answers to these questions come into focus.

The GPS Revolution 

When the long-desired animal-tracking revolution arrived, it brought many surprises about where migratory ungulates go, and how they interact with barriers.

On November 12, 2013, biologist Adele Reinking’s team collared pronghorn Yellow-13 on the west side of US 789, 11 miles south of I-80. When Reinking later mapped the data on her computer, the thousands of GPS fixes of Yellow-13’s movement were all arranged into a mysteriously precise rectangle with an area of less than six square miles. 

Zooming in, Reinking realized that the day after the pronghorn was collared, it had made its way into a grazing enclosure in a natural gas extraction area. Yellow-13 remained inside that same fenced area for 16 months, until April 7, 2015, at which point she escaped confinement, only to die of unknown causes at the end of September.

“So, most of the last two years of her life were spent in a very small, highly-developed area that she was likely not able to leave because of fencing,” Reinking said. For a species that can run 50 miles per hour and range over hundreds of miles, one can only imagine the feeling of being trapped in a wire cage under open Wyoming skies.

The seeds of the GPS revolution had been planted decades earlier, at about the same time I-80 was completed across Wyoming. NASA first experimented with a satellite tracking collar on a Jackson Hole elk named Monique early in 1970. The technology was cumbersome and prone to malfunction, but it was the start of Wyoming’s role in an animal tracking revolution. 

Later, very high frequency (VHF) radio telemetry collars became the standard wildlife tracking technology used by biologists, though they required laborious triangulation fieldwork and often revealed just a handful of data points. Even so, radio tracking yielded dense information about winter ranges where animals spent a lot of time, and informed a major push to conserve those ranges for big game herds during the 1980s and ’90s. 

By the early 2000s, satellite monitoring of wildlife became much more accessible to biologists due to the development of GPS collars with a year or more of battery life. The initial iteration was “store on board” GPS collars that weighed very little and held the satellite antenna and storage chip in compact boxes worn around an animal’s neck. 

These devices communicated with satellites to pinpoint locations at programmed intervals and kept the data on the internal chip. After a year or two, a release mechanism activated and dropped the collar to the ground. The biologist then retrieved the collar from the field and downloaded the data.

Despite the inconvenient delay in accessing data, store-on-board collars represented a major technological leap forward, and they ignited a rapid advancement of migration science in Wyoming. The patchwork of radio telemetry data gave way to a clear picture showing how animals move 24 hours a day, through all four seasons and multiple years. 

Fast forward to 2020, and GPS collars have advanced further to real-time collars linked to remote computers via the Iridium satellite network. Such devices can log locations every few hours for two to three years, feeding a constant stream of information to researchers in the office. 

Biologists coupled this wealth of data with computerized statistical methods to open up vast new analytical avenues and questions. In recent years, biologists have produced landmark studies on the outsized nutritional contributions of stopover habitat, and shown how migration dynamics are a complicated dance with springtime snowmelt and the greenup of plants. Such discoveries have enabled a shift from a focus on protecting just winter range or summer range to a holistic approach that includes both seasonal habitats and the migration corridors in between. 

“With the advent of GPS, it has shown a much finer scale of habitat use and movement by animals than was available when using the older style of VHF,” said Scott Gamo, environmental services manager for WYDOT. “The technology had to catch up to ideas and show if they were wrong or right or different.”

In the last ten years, the data trove has revealed that I-80 is a nearly complete barrier to wildlife movement. Scientists have now created maps for virtually the entire length of the highway in Wyoming, showing animal movement patterns like tangles of spaghetti balled up along the right-of-way fences. 

The stories coming out of the data allowed scientists and managers to dig into the specifics of how I-80 impacts wildlife habitat across southern Wyoming.

For a larger map with text, download the PDF >

Broken Habitats

For Hall Sawyer, a biologist with Western EcoSystems Technology, Inc. (WEST), the power of mapping revealed the I-80 barrier early in his study of the 150-mile-long Red Desert to Hoback Migration Corridor. The data showed how in the severe winter of 2010-11, mule deer pushed south as they sought relief from heavy snows, only to pile up along the interstate near Point of Rocks. They were cut off from potentially better habitat beyond I-80, where there is often reduced snowfall. 

That same winter, a similar movement to avoid snow played out further east at Dunlap Ranch near Shirley Basin. In early 2011, graduate student Katie Taylor tracked 27 collared pronghorn to evaluate the effect of wind energy development on pronghorn habitat use. As the particularly harsh winter set in, 13 of the Shirley Basin pronghorn made a notable movement west toward Seminoe Reservoir, likely seeking relief from deep snow. All 13 animals died throughout the relatively poor desert scrub habitat several miles north of I-80, representing half of the Shirley Basin study population. 

A far milder outcome played out in a control population of 35 more Platte Valley pronghorn south of the interstate, where only one animal died in February 2011. Taylor surmised that better-quality sagebrush on winter habitat, plus excellent summer range east of Elk Mountain, might have contributed to higher survival for the south-of-I-80 herd. The habitats that meant the difference between life and death for the two study populations were separated by only a few miles—and four lanes of interstate traffic. 

“Once we looked at several of these GPS datasets together, it just became clear that the interstate blocks ungulate movements, not just in one spot, but for a couple hundred miles across southern Wyoming,” Sawyer said. “And that movement barrier reduces the options that animals in these populations have…. That’s problematic during severe winters when big game are trying to find areas with less snow.”

Researchers who study pronghorn along I-80 can count on their fingers the collared study animals that ever crossed the highway. They can recall the individual animals, where the crossings happened, and what happened when animals got stuck.

Taylor said only one doe pronghorn from the Dunlap Ranch study ever crossed the “huge barrier” of the interstate. “We were pretty surprised to see that,” Taylor said. “That individual crossing there was a bit baffling to us. It is interesting to see an animal [move] across that high-level of a disturbance corridor. … to do that once is really impressive.” 

“And somehow, she made it back across without dying,” added Taylor’s adviser Jeff Beck, a professor in the University of Wyoming’s Department of Ecosystem Science and Management. “How she did that, you got me. Katie and I, we thought that was crazy.” 

The mystery of how this doe crossed I-80 was never solved definitively, but a decade of subsequent GPS data, trail camera research, and tracks have suggested that a passage under I-80 at the Platte River Bridge may be providing limited connectivity for individual pronghorn in the Shirley Basin population, and also for a few mule deer. 

Yet such stories of wildlife crossing the highway using infrastructure not designed for them are an extremely rare exception. Of 186 pronghorn that biologist Adele Reinking fitted with VHF radio and GPS collars, only one crossed I-80. “Her ID was Orange 25,” Reinking recalls. She collared the pronghorn 50 miles south of I-80, a little north of Baggs. “I saw her living at the big Love’s gas station in Wamsutter on the north side of I-80.” Reinking expects that Orange 25 used the underpass at the adjacent interchange to get under the interstate, but she isn’t certain because the collar battery failed and the data was never retrieved.

Ben Robb, a recent master’s degree graduate of the Wyoming Cooperative Fish and Wildlife Research Unit, compiled pronghorn data from multiple studies along I-80 from 2002-20, amounting to 400 animals and 700 animal-years. The massive dataset covers a region between Cheyenne and Evanston and stretches north of Pinedale in the west. At the time, there were likely no other pronghorn datasets of this scale in the American West.

Across all those pronghorn in all that time, Robb found only six with functioning collars that ever crossed the interstate. Three of these were at the Table Rock and Bar X Road areas in the Red Desert, one was at the Blacks Fork River crossing near Lyman, and two more crossed under the Platte River bridge at Fort Steele. 

The volume of data has enabled Robb to calculate, for the first time, how likely it is for a pronghorn near I-80 to negotiate the barrier in any eight-hour period. “The odds that a pronghorn successfully crosses the interstate is equivalent to a royal flush in Texas Hold ‘em,” said Robb, a novice poker player. “Technically it’s a little more likely for a pronghorn to cross, but we’re talking odds of 0.00009 vs 0.00003 here, so that’s splitting hairs.”

Now, after decades of research and hundreds of tracked animals, we can say with certainty what biologists in the 1970s could only guess at: I-80 is virtually a complete barrier for pronghorn. Keep in mind that Wyoming is a state with 436,000 pronghorn, or 47 percent of the 916,000 pronghorn in North America, as of 2017. Given that Wyoming is the pronghorn capital of the world, the rarity of interstate crossings is astounding.

However, none of that means that animals don’t want to cross. 

When I placed trail cameras at Dana Ridge and the Platte River bridge, the videos documented pronghorn eyeing underpasses that are fenced off, presumably to manage livestock. The clips seem to show pronghorn gazing through the barbed wire and beyond to the opening underneath the highway, as if wanting to cross. Seeing no way through, they walk away instead.

The seldom few that cross the interstate anyway do so in less than ideal conditions, like busy road interchanges or by fighting their way through difficult fences. “I find it exciting that pronghorn are using locations that are not designed with them in mind,” Robb said. It speaks to the possibility that pronghorn would readily use crossings that are designed for them. The evidence suggests that if offered a little more help, their wild instincts would readily reconnect this fragmented landscape, mending vast habitats and benefitting movement and survival.

Looking Forward

Back in 1976, Lorin Ward’s report on deer along I-80 ended with this prescient recommendation: “Cooperation between highway designers and wildlife managers can effectively reduce the number of deer-vehicle collisions.”

Today, Wyoming Game and Fish Department and WYDOT have teamed up on the Wyoming Wildlife Roadways Initiative, a collaborative effort between agencies. The coordination is empowered by an enormous amount of data that can help to identify potential crossing designs and locations, reconnecting suitable habitat both on I-80 and across the state.

The initiative evolved out of WYDOT and the Wyoming Game and Fish Department’s Wyoming’s Wildlife and Roadways Summit held in Pinedale in April 2017. The conference set in motion efforts to identify the top wildlife-roadway “opportunity zones.” These represent the most pressing areas for improving wildlife passage across Wyoming’s highways, using criteria like migration corridor data and wildlife-vehicle collisions. Of the 43 projects identified, eight are along I-80. 

The agencies are using GPS technology and mapping to share wildlife-roadway information with the public through the Wyoming Wildlife Roadways Initiative website. All the data is helping to design solutions that range from simple and inexpensive, to complex engineering feats that cost in the millions or tens of millions of dollars. 

Starting on the simple end, improving fences to benefit wildlife is the easiest to implement. The most common actions are removing fences or changing woven-wire fences to wildlife-friendly designs. Such actions help improve connectivity on habitats adjacent to I-80 and provide an ecological benefit even without crossing structures for I-80.

“Someone asked me what’s the best way to invest our money, and I think fence modifications,” Reinking said. Significant gains could be made for Red Desert pronghorn by improving fences in ranges north and south of the highway, she thinks. “I would prioritize that over making it easier to cross I-80. I think the fencing is a much easier, faster, lower investment fix, than an overpass, which we know for pronghorn is almost required.” 

Wildlife movement data can help target these fence retrofits efforts. Rawlins Bureau of Land Management (BLM) Office biologist Mary Read consulted with Reinking to identify fences that were blocking pronghorn movement, working off an initial $50,000 budget. In 2018 and 2019, the BLM and partners funded more than $250,000 in fencing work, addressing almost 22 miles of range fence in 55 locations. While most of these projects are not immediately adjacent to I-80, they reduce the movement barriers for herds that are also dealing with the highway.

“When Mary Read came to us with $50,000,” Reinking said, “that is not enough for an overpass, but it can fix a hell of a lot of fences.” 

The next step up for restoring connectivity is modifying existing infrastructure like underpasses and bridges to enable or enhance wildlife passage. There are more than 200 existing underpasses between Cheyenne and Evanston for livestock and machinery, and many have the potential to be retrofitted to enhance wildlife movement. Hall Sawyer and Bill Rudd compiled a 2006 report documenting some of these existing structures along I-80. 

Ben Robb has placed dozens of camera traps at existing machinery underpasses and bridges to monitor any wildlife usage. “Spoiler alert: We are finding that underpasses that have a fence on them are not used by pronghorn,” Robb said. One way to increase use of these structures could be to retrofit woven-wire fences and use smooth bottom wires that are high enough for pronghorn to scoot under. Such retrofit projects could build on the knowledge acquired by 1970s crossing projects at Dana Ridge and the Sisters, and more recent underpasses built at Trappers Point, Nugget Canyon, and Baggs (see map). 

Then there is the option of creating new crossing structures: underpasses or overpasses. There is wide agreement that the best solution for pronghorn to cross the interstate is a wildlife overpass. In Wyoming, that impression is largely shaped by the success of the Trappers Point overpass over the two-lane US 191 near Pinedale, Wyoming. A 2016 Wildlife Society Bulletin paper by Hall Sawyer, Patrick Rodgers, and WYDOT’s Thomas Hart found that pronghorn vastly preferred to use overpasses compared to adjacent underpasses. 

Migrating pronghorn began using the Trappers Point overpass immediately after it was completed in 2012. During the next three years, the overall project of 12 miles of fencing, six underpasses, and two overpasses eliminated pronghorn-vehicle mortalities, and reduced mule deer road mortalities by 79 percent. Mule deer made more than 40,000 crossings, and pronghorn made more than 19,000 crossings. Many of these were back-and-forth movements that allowed animals the flexibility to intermingle during the autumn rut and respond to changing environmental conditions on winter ranges. 

These impressive numbers for a 12-mile project on a two-lane highway only begin to suggest the magnitude of connectivity that could result if crossing structures were built at key places along Wyoming’s 400 miles of I-80. While Wyoming has no I-80 wildlife overpasses so far, in Washington, Nevada, and Utah there are several that bridge four-lane interstates, proving the concept is feasible. The track record for these structures goes back to 1975, when Utah built the first wildlife overpass in the United States across Interstate 15 near the town of Beaver.

In the absence of an overpass, anecdotes show pronghorn use interstate underpasses under certain conditions. UW biologist Jeff Beck once saw a group of about 15 pronghorn crossing under the Wolcott Junction interchange of I-80, heading south toward Saratoga. In September 2019, transmission line inspector Waylon Dyess of Rock Springs saw about 50 pronghorn cross under the interstate from south to north at the Tipton interchange, on the west edge of the Great Divide Basin. In the winter of 2019-20, Phil Damm, Fort Bridger biologist for Wyoming Game and Fish Department, saw tracks that substantiated reports of hundreds of pronghorn crossing east to west at the US 789 underpass north of Baggs. 

“I have had professionals outside of Wyoming tell me that pronghorn don’t use underpasses, end of story,” Robb said. “And I hope [my research] could change the story, that actually, the underpasses may not be ideal, but they will use it in the absence of other options.”

Wyoming biologists generally agree underpasses could also be a good solution for mule deer or elk when placed in the right locations. It’s possible that such structures, combined with exclusion fencing, could help prevent deadly elk collisions that have occurred near Little America, Jim Bridger Power Plant, and Rawlins in recent years.

There are a number of hurdles in the way of building new crossing structures across I-80. These range from design challenges due to drifting snow conditions and proximity of the railroad, to land ownership issues that would require coordination between public agencies and private interests. However, the biggest challenges may lie in current policy priorities and limited funding streams.

When WYDOT and the Wyoming Game and Fish Department prioritize wildlife-highway projects, restoring habitat and migration movement is only one of several considerations. Projects that are most likely to improve driver safety tend to rise to the top in terms of urgency, and on the local level some two-lane highways are greater hotspots for wildlife-vehicle collisions. Overpasses on I-80 may benefit wildlife immensely, but they might not do a lot for driver safety.

There is also the sheer cost. Along I-80 at the Pequop Range and Silver Zone Pass in Nevada, a series of three wildlife overpasses, numerous underpasses, and fencing required an outlay of about $20 million. Depending on the location, a project could cost more in Wyoming if a separate overpass were required to go over an adjacent access road, not to mention the Union Pacific railroad. “We don’t want to just pour [animals] out across the interstate and right onto the railroad,” said Scott Gamo, environmental services manager for WYDOT. 

Despite WYDOT’s buy-in on the importance of wildlife connectivity, sufficient money for that purpose alone won’t come from the agency, so the state would need to find other funding sources. A federal appropriation would be one solution, and there are potential ways to raise funds through grants. For the Dry Piney wildlife crossing project over a two-lane highway near LaBarge, WYDOT secured a $14.5 million grant and additional matches from Wyoming Game and Fish Department and other partners for a total of $18.5 million. Construction of up to eight wildlife underpasses and associated fencing will begin in 2022. 

The collaboration is a realization of Ward’s call for highway engineers and biologists to work together. Such interagency projects demonstrate how safer highways and wildlife connectivity are complementary goals.

“We [at WYDOT] want to do our part to certainly minimize if not eliminate mortalities for wildlife if we can,” Gamo said. “If we can do that to benefit people and wildlife, that is obviously a win-win…. A bigger push now, than it was in the past, is looking at the habitat. It’s moving that way for WYDOT.”

The Wyoming Game and Fish Department’s statewide wildlife-roadway work with WYDOT continues long-standing habitat and research efforts that Hepworth and others undertook along I-80 in the 1960s and ’70s. “It’s exciting to see how evolving technology, like GPS collars, has allowed us to better understand wildlife movement in relation to I-80,” said Wyoming Game and Fish Department Deputy Director Angi Bruce. “Game and Fish is committed to working with WYDOT and other partners to rely on this expanding data to improve wildlife connectivity and public safety on I-80 and throughout the state.”

Finally, engineers and biologists have to decide where to site crossing structures to best restore movement across I-80, when corridors have been severed for 50 years. To analyze the options, Ben Robb completed an analysis of high-quality pronghorn summer range and winter range, and then modeled ways to “connect the dots” across I-80. He successfully defended his thesis on this research in fall 2020.

“This will give us valuable information of feasible options that can let pronghorn continue to freely move, and have the right to roam in Wyoming,” Robb said.

Any future gains for wildlife connectivity, both on I-80 and elsewhere, will likely be built on a foundation of public interest, collaborations, and creative funding. There are murmurs that a federal infrastructure bill could include funds for wildlife projects, but if experience is any indicator, Wyoming’s own initiative will be the deciding factor. 

As of this writing, work has begun to enhance wildlife connectivity in the Halleck Ridge area of I-80, just east of Dana Ridge. This is the Wyoming Wildlife Roadways Initiative’s number two priority wildlife-roadway project for all of Wyoming. WYDOT contracted with Western EcoSystems Technology (WEST) to analyze GPS data and create a list of potential enhancements. The project is looking at ways to upgrade fencing or enhance culverts or underpasses to help animals cross. WEST has also contracted with an engineering firm to examine potential locations for an overpass and do initial drawings. The planning doesn’t mean an overpass will be built, but that it could be one of the options on the table for WYDOT’s consideration. Fence crews are already working in the area.

If a large-scale wildlife overpass or underpass project does come to fruition at Halleck Ridge, that could lay the groundwork for future efforts along the length of the interstate. Research suggests intriguing possibilities, most of which match with priorities set by WYDOT and Wyoming Game and Fish Department. 

Crossing structures on I-80 could enable mule deer and pronghorn corridors that start as far away as Jackson Hole or Yellowstone to continue across I-80, and even into Colorado, connecting the great wildlife winter ranges of the two states. In particular, biologists wonder how much father mule deer on the 150-mile-long Red Desert to Hoback mule deer corridor might go if I-80 didn’t block them at the southern end. 

Near Fort Steele, Creston Junction, Wamsutter, or Table Rock, crossing structures could enhance pronghorn winter range movements. If a crossing structure were built in those areas, there is a chance that pronghorn north of the interstate would find a way to move a long distance south. In 2019, Ben Robb tracked a pronghorn from the Table Rock area to near Sunbeam, Colorado along the Yampa River, a distance of 100 miles. 

Further west of Green River, I-80 wildlife crossings could help relieve connectivity issues along WY 372 created by a solar farm. “It almost looks like that place needs a relief valve because animals get trapped in there,” Gamo said. “If the animals could have an outlet to the south there, that may alleviate some of those issues.” An ongoing study by Western EcoSystems Technology will help pin down pronghorn movement patterns in this region and evaluate whether fence removals and a 50-meter movement corridor between the solar farm and WY 372 could help pronghorn. A separate study is looking at Uinta Range mule deer movements from The Sisters to Kemmerer. 

Since that day in October 1970 when I-80 was completed across Wyoming, 50 years of research has clearly laid out the wildlife problems, and the options to fix this barrier once and for all. Any connectivity projects could stand to make a large difference for wildlife along I-80, effectively multiplying the amount of habitat available. 

“A lot of places just don’t have that open swath of sagebrush habitat that Wyoming does, and that’s something to be proud of,” Ben Robb said. “Rather than just restoring a square mile, you would be practically doubling the access to the habitat, just by hopping a road.” 

Across the Mountain West, it’s hard to imagine a bigger opportunity for restoration.

Gregory Nickerson is a writer and filmmaker for the Wyoming Migration Initiative at the University of Wyoming. Watch his 12-minute film about wildlife movement and I-80, 400 Miles to Cross.

By Kylie Mohr

Scientist Rob Ament and then-grad student Matthew Bell were on a quest. In the Dutch city of Rotterdam for a conference on ecology and transportation in 2018, they wanted to find a pedestrian bridge made of an entirely new material-fiber reinforced polymer, or FRP, plastic. They had hopes of putting it to use on a bigger scale for wildlife back in the United States. But after being stood up by the company who made it, the two Montana researchers were at a loss. 

“So we went to our hotel and we talked to the woman at the front desk,” said Ament, the Western Transportation Institute’s road ecology program manager. “We said, ‘This is crazy, we’re looking for these plastic bridges.’ We showed her a picture that we’d seen on the website of this company. And she goes, ‘I know where that is.’” 

She pulled out a map. Bingo. 

While in the Netherlands, Ament and Bell also managed to find the world’s only wildlife overpass made of FRP. They think the material has the potential to solve some of the problems of traditional wildlife crossings, which are designed to shepherd animals over or under busy roads. Wildlife crossings in North America are usually large concrete structures, sometimes with foliage on top, spanning highways. This makes them expensive, permanent, and slow to build, and requires carbon-intensive concrete and other materials.

People like Ament are rethinking what goes into the crossing structures. The potential for lower maintenance costs and quicker construction could solve some of these problems and get more crossings on the landscape. 

“We know our highways are barriers and we didn’t design them with landscape connectivity and wildlife movement in mind,” Ament said. “They just weren’t built that way and now we’re retrofitting to reconnect the landscape.” That retrofitting is increasing in pace. The first wildlife bridge in the US was built in Utah in the 1970s. Today, Banff National Park in British Columbia boasts almost 40 underpasses and six overpasses and new ones are popping up every year over highways all across the West. 

Scientists want to make wildlife crossing structures cheaper, more versatile, and easier to build and maintain, and combining resources can help. Eleven states, Parks Canada, and the Canadian province of Ontario collectively put up $1.2 million under a US Department of Transportation program to improve rural travel, which includes helping drivers avoid hitting wildlife. The Western Transportation Institute, the country’s largest university-based research center focused on rural transportation issues based at Montana State University, won the funding with their creative proposal. Wildlife overpasses and underpasses with fencing are fairly well studied, so Ament and his team took a different approach, plunging into FRP research. Who makes FRP bridges, how could they be designed to work at a bigger scale, what are their strengths and weaknesses? 

“The question isn’t, ‘Do they work?’ but, ‘Can we do them with new materials with the idea of trying to bring the cost down,’” Ament said. Bridges have traditionally been made of the same three materials—steel, concrete, and wood—for hundreds of years. “It hasn’t ever changed,” Ament said. “Isn’t that amazing? We’re just starting to introduce our fourth material.”

Six areas were nominated as sites to build out the solution to the funded challenge. California’s two-lane US 97 in Siskiyou County was ultimately chosen. A site hasn’t been finalized yet, but it’ll likely be on a ridge above Grass Lake. Project proposals state that Caltrans maintenance staff remove six or seven animal carcasses monthly from the highway in this stretch and between 2015 and 2019, California Highway Patrol recorded that vehicles struck 68 mule deer and five elk. Numbers are likely higher, since not all incidents are reported. 

Now a team of engineers, wildlife biologists, and road ecology gurus from California to Montana are drawing up plans for an FRP overcrossing there, which will be the first bridge of its kind in North America. They’ll also design accoutrements, like fences and sound barriers, once a site is finalized. They hope doing time-intensive research and consultation now will work as a blueprint to expedite the process in the future and show other clients that the material can work in practice and not just on paper. Caltrans has already expressed interest in a second structure if the process goes smoothly.

“The idea of someone trying to do something new and different, the potential uses of something like that, interested us from day one,” said Wesley Stroud, a senior environmental planner for Caltrans. 

The challenge now is scaling up FRPs for the bigger wildlife seen in the western United States. In the Netherlands, “they’re looking at hedgehogs and badgers, and we’re looking at elk and wolves,” said Bell, now a research associate at the Western Transportation Institute and the lead materials researcher on this project. “They don’t compare.” The Northern California bridge will need to be between 30 and 50 meters wide to convince elk, skittish in tight spaces, that it’s safe enough to cross. Bell is working with different companies and materials to determine the best fit for the project; structural engineer Damon Fick is making sure the eventual bridge doesn’t collapse. 

FRPs are made using materials like crude oil, natural gas, chlorine, nitrogen, glass, and sometimes recycled plastics. These materials can’t be welded like steel, so the researchers are considering different bolted connections to help the bridge be as wide as it needs to be. Fick, an assistant professor of civil engineering at Montana State University, said FRPs bring about a unique set of engineering concerns he’s excited to tackle. One that’s on his radar is “slouching,” which can happen with composite materials that are less stiff than steel or concrete. “The bridge won’t necessarily fall down,” Fick said. “But it’s a cosmetic or a serviceability issue. Nobody wants to walk underneath a beam that looks like it’s sagging.” Selecting the right manufacturer of FRP and designing it properly will help solve this problem. While there’s inherent risk and logistical challenges of using something new and trying to scale it up, the attitude across state lines is gung-ho.

Researchers think there are strong reasons this material is worth pursuing. They’ve poured over case studies that show the average FRP bridge is half the weight of a steel bridge with the same strength and is five times lighter than its concrete equivalent. Smaller bridges—not this particular project over US 97—could be assembled like Legos, with precast molded blocks being plopped into place. This could theoretically mean quicker construction with fewer traffic detours and re-routes as well as the possibility for bridges that aren’t as long or wide as the California design to be picked up and moved if migration routes change. And FRP materials can last four times as long as, say, wildlife fencing made of wood.

“Generally speaking, FRPs are an extremely strong material, they make construction a lot easier, they last longer, there’s little maintenance required,” Bell said. “Depending on the way your materials are used, they can even be fire, impact, or UV resistant.” 

The first few FRP bridges likely won’t be too much different in overall cost, but the hope is that in time costs will come down when less preliminary research, materials reconnaissance, and design work is needed to lay the foundation. Avoiding sticker shock is a strong motivator: a recent price tag for an overpass near Banff, Alberta, clocked in around $4 million and average costs for wildlife crossing construction range from there up to $10 million.

Potential future savings include lower construction method costs, less time to complete a structure, and less maintenance compared to conventional methods. While wildlife crossings with the material are unchartered territory, Bell said pedestrian bridges using FRPs are bid against conventional methods and come up the same price or cheaper. For now, some structural components of the bridge in California—like fence posts or sound barriers—could be fully FRP. Others might be a hybrid of FRP on the outside and concrete on the inside to leverage the beneficial properties of each.

The project is in its design phase. Caltrans is looking for funding partners to pay for construction. If all goes according to plan, construction will occur in the summer of 2023. While there’s still a lot to learn about how FRP bridges will work for North America’s larger mammals, the innovative material could change the landscape for wildlife connectivity. 

“It needs to be looked at as a whole conservation goal as well as an economically sustainable goal when it comes to what we’re trying to do,” Bell said. “It could definitely be the future of wildlife crossings.”

Kylie Mohr is an award-winning reporter based in Montana who recently earned a master’s degree in environmental journalism. She is currently an intern at High Country News. Learn more about her work at kyliemohr.com.

Text and images by Claire Giordano 

My mom tells stories of a magic road. It wound from a gleaming blue alpine lake to the desert below. It required no gas, didn’t wear out brakes, and had the most beautiful vistas. From the top, a car traveling at 50 miles per hour could be slipped into neutral and coast through every turn to the arid land below. This road, winding gracefully eastward from Lake Tahoe to Carson City, was designed by highway engineer Ernest Muller. It was Grandpa’s road. 

Ernest, or Big E as he was known due to his distinctive signature with an oversized “E” and a line of waving squiggles not unlike the undulating desert landscape, worked for the Nevada Highway Department (now the Department of Transportation) for 37 years. When he retired, he continued to walk the desert as a surveyor outlining land and water rights. 

As the breadwinner for a family of seven kids, Ernie spent most of his time wandering the desert with pen, paper, and plans in hand. His youngest daughter Virginia (my mom), recalls how, “My dad was happiest outside. Home was crowded and loud, and I treasured the days I got to join him ‘out in the field’ as he called it. I was always struck by the silence. I think he was the most at home with an endless view of cacti, sand, and sagebrush.” During the long days outside Ernie filled his pockets with small details from the landscape: rocks, barbed wire, date nails, pottery shards, and arrowheads. 

Over a lifetime of wandering, Grandpa’s yard and basement filled with rocks. Each represented a relationship with place forged over a lifetime of walking, working in, and learning from the desert. My favorite activity when I saw him once each year was to sit quietly amid the piles of stones and arrange them by color. When I was lucky, he told me their stories.

I remember how his hands looked like the land, crisscrossed with wrinkles and suntanned brown. He smelled like the desert: sage and petrichor. Sometimes it seemed the edges between person and place blurred—khaki clothes and grey hair a mirror of golden yellows, sun faded brown, and silvery pines beneath a cobalt blue sky. 

Ernie was unusual among his fellow engineers. He worked out of Carson City (the state capitol), and when most of his peers visited other cities, they completed a very brief obligatory site walk before retiring to air-conditioned restaurants to discuss development plans. Not so with Big E. The minute he stepped out of the car he always headed straight into the desert regardless of the weather. During one notorious visit to Las Vegas the local engineers followed him from the rental car into a sun cracked valley. All struggled to keep up with his long legs over the eight-mile trek in 100+ degree heat. “They didn’t even stop for lunch,” his son Jon recalls. “My dad always had a pocketful of peanuts and that was it. The engineering department still talks about that day 25 years later.”

Grandpa left an equally large impression on the roads of Nevada. Highway 50, infamously known as the “loneliest highway in the nation,” crosses the entire state of Nevada from west to east. It was one of the largest projects he worked on, and Ernie engineered an incredibly difficult section. He designed the safe and beautiful route through the Sierra mountains from Lake Tahoe to Carson City. 

Grandpa “took great pride in engineering not only the best road, but also a road that had the least impact. He was always looking for ways around streams and how to minimize blasting rock,” recalls Jon. Ernie was dedicated to crafting a road that felt part of the landscape and encouraged people to experience the beauty of where they were. “Dad insisted on making the road look like it was exactly where it should be. He thought of everything. From requiring tunnels for deer to hiding the entry road to a development behind swales of earth, he engineered each turn to maintain the beauty of the desert. He even helped pioneer the use of browned guard rails because he hated how the reflective metal was visible from miles away when he was out surveying.” 

Decades later, it is no longer possible to coast down the entirety of Grandpa’s old two-lane road. Since completion in the 1960s, sections of the highway were altered to accommodate higher traffic volumes. But, I believe the man behind the road lives on in the original path carefully plotted through the mountain passes. Grandpa is also in the box of stones willed to me and carefully arranged in my studio beside rocks I collected on my hikes and painting expeditions. When I sit for hours painting outside, I often think of Grandpa and the places we can go because of his roads. And I imagine the intersecting lines our creations trace across a landscape.

Claire Giordano is an environmental artist and writer following the interwoven patterns of people, place, and climate change. See more of her work at claireswanderings.com.

By Aubin Douglas

My first visit to the Great Salt Lake was a graduate course field trip to the Bear River Migratory Bird Refuge. Upon arrival, I was awestruck by the sheer number and variety of birds. Acrobatic barn swallows dove and swooped amongst the bridges; red-winged blackbirds perched atop cattails while calling to each other; scampering plovers chased brine flies along the shoreline; graceful American avocets waded through the shallows; swift-moving grebes and ducks dove below the water’s surface and reemerged with mouthfuls of invertebrates, plants, or seeds; and stoic American white pelicans glided along the water’s surface at a lackadaisical pace. The lake was truly a bird metropolis. 

This is possible due to the freshwater inlets that flow from the Wasatch Mountain Range into the eastern side of the lake, creating ideal wetland habitat for migrating birds. Great Salt Lake wetlands comprise 75 percent of Utah’s total wetland acres, a true oasis in the desert. In fact, over 7.5 million birds representing 250 different species call the Great Salt Lake home at one or more times during their annual migrations, which is why all five of the lake’s bays are recognized as globally Important Bird Areas. According to the National Audubon Society, the Great Salt Lake and its wetlands are one of the most important wetland habitats located in the Pacific Flyway.

At the same time, the West is one of the fastest-growing regions in the US, and Utah is no exception. The state has one of the highest human population growth rates in the nation and its population is expected to double by 2065; much of that growth is predicted to occur along the Wasatch Front, a rapidly expanding urban corridor along the eastern edge of the Great Salt Lake. The Government of Utah is enticing businesses from around the globe to move to the Wasatch Front with tax incentives and by creating new infrastructure such as roads, housing, commercial and industrial districts, a new state prison, a new inland port, and a new terminal at the international airport. Those in government highlight the Wasatch Front’s “sense of place and community,” natural beauty, and adjacency to wildlife and the great outdoors as reasons why businesses and people should immigrate from other states and countries to live and work there. 

These two concepts of urban expansion and beautiful natural areas seem at odds with each other. How can one rapidly expand an urban center that’s already pinched by two natural landscape features—in this case the Wasatch Mountain Range to the east and the Great Salt Lake to the west—and expect to maintain adjacent rolling farmland, lush wetlands, spring creeks, mountain meadows, and the diverse wildlife that depend on these habitats? Currently, the Wasatch Front is developing at the cost of these ecosystems, trading sense of place and natural surroundings for sprawling suburbs, shopping malls, and more roads. The truth is, growing cities in the West can continue to prosper while maintaining the unique and important habitats that support the wildlife who depend on them. All it takes is some forethought, cooperation, and bioregional planning.

In 2016, I entered Utah State University’s master’s program in bioregional planning. Bioregional planning is an iterative, transparent, community-based method for landscape-scale planning. In collaboration with local stakeholders and community members, bioregional planning takes into account the environmental, social, and economic qualities of a landscape and then initiates public discourse to generate potential alternative futures for a region. The ultimate goal is to generate several different visions for future development that local communities and stakeholders wish to see either realized or avoided. After all, it’s as important to understand your goal as it is to understand what should be avoided in the future.

During my introductory courses at Utah State University, I learned how important the Great Salt Lake ecosystem is, and just how imperiled it has become from upstream water diversions and nearby urban development. The more I learned about the importance of the Great Salt Lake to millions of birds, the more I wondered how this natural wonder would fare in the face of a rapidly expanding population and developing urban area; this is what ignited my interest in what would become my thesis project.

As a bioregional planning student, I wanted to know how the nearby urban area was incorporating the Great Salt Lake and Utah’s most important wetlands into state, regional, and county master plans. Through this inquiry, I carefully reviewed the planning of new construction projects along the Wasatch Front, including a new major highway—the West Davis Corridor—which is slated to be built along the southeastern edge of the lake around Farmington Bay. I also learned of a regional development plan led by the Wasatch Front Regional Council that would accommodate projected population growth out to 2040: The Wasatch Choices 2040 Regional Vision. Lastly, there were recent news articles featuring debates involving Salt Lake County, Salt Lake City, and the State of Utah over how to develop a quadrant of land directly south of Farmington Bay; this is where the new state prison, new terminal for the international airport, and new inland port are intended to be built.

I noticed the planning documents for these projects did not fully address the potential impacts to the Great Salt Lake wetlands and its wildlife. I saw an opportunity to do a project that fulfilled my thesis degree while simultaneously aiding local planners and government officials by quantitatively assessing those impacts as a preliminary step in the bioregional planning process. I knew it was impractical to complete an entire bioregional plan on my own, so to keep my project feasible, I focused the scope of this project on identifying and assessing the impacts these three major development projects would have on the current migratory bird habitat around Farmington Bay.

While I began my thesis research, I looked for other places in the West where bioregional planning was being employed to grapple with the issue of rapid population growth. I found that other areas also face the challenge of accommodating more people while managing the beautiful natural areas that surround them and make them unique. So, what cities and regions are working to not only accommodate new development in important natural and recreational areas, but also mitigate the potential negative impacts on local and migrating wildlife? 

In a similar 2016 project, local stakeholders in Moab, Utah invited my Bioregional Planning Studio cohort at Utah State University to lead a bioregional planning project to identify alternative potential futures for the region out to 2040. With stakeholder engagement and collaboration, we identified areas amenable to varying types of local land-uses, including new development, agriculture, recreational activity, natural resource extraction, and conservation of water and wildlife resources. After we presented our findings, the local officials, planners, and community members interacted in a Geodesign Workshop to select aspects of the potential futures and create an agreed-upon regional vision to plan for in the coming years.

Bioregional planning has also been implemented by the Crown Managers Partnership, an international partnership among various agencies in Montana, Alberta, and British Columbia. This team is using a planning method that addresses socio-ecological issues and topics spanning the entire Crown of the Continent ecosystem. Using a similar planning method called Landscape Conservation Design, the Crown Managers Partnership, along with interested stakeholders and communities, is bringing the region’s existing science and land-use plans into a landscape scale vision that considers not only wildlife and ecosystems, but regional cultural, social, and economic priorities, as well. This is an iterative, ongoing project that will inform and guide planning and development into the future for this international region.

With these project examples in mind, I developed and implemented a bioregional planning-based method that identified and assessed potential future land use conflict between the three proposed major development projects and the critical migratory bird habitat around Farmington Bay. I first mapped the three development projects and then grouped the different types of development into four main categories—highway, commercial, residential, and industrial—to identify and assess how each of these development types were impacting existing migratory bird habitat. 

Once I had categorized the spatial data for the three development projects, I collected migratory bird habitat data from the US Geological Survey’s Gap Analysis Program. Since there are over 250 species that use the lake and its associated wetlands, I selected habitat data from five representative species for each of the three main bird guilds—shorebirds, waterbirds, and waterfowl—that use the lake and its adjacent wetlands. I combined the habitat data of the five species to make habitat maps for each guild. For example, the shorebird guild’s map combined habitat data for American avocet, snowy plover, Wilson’s phalarope, willet, and long-billed curlew. After creating the habitat and development datasets, I looked for spatial overlaps that could indicate potential land use conflict between development and conservation of important bird habitat. I then assessed the percentage of each project in conflict with existing migratory bird habitat within the study area.

I was surprised to find that every development project showed a substantial amount of conflict with all three of the bird guilds I assessed. I realized that it would be infeasible to recommend that the regional planners and developers avoid all areas identified as in-conflict with bird habitat, so I decided to make recommendations based on protecting the most important habitat within the area. I performed a “hotspot analysis” by assessing conflict between the proposed development projects and areas where four or more representative species’ habitats overlapped. This revealed the areas where proposed development would displace the most important habitat—habitat used by at least several of the representative bird species—in the study area.

Among the three projects, one stood out: 88 percent of the West Davis Corridor, or 2,090 acres, conflicted with bird habitat. This planned highway will displace agricultural fields, pastures, and wetlands, which are ideal spillover habitats for many of the birds that migrate through the area. In the hotspot analysis, over 1,600 acres of this project were in conflict with habitat for four or more representative bird species. This finding alone should be cause for further research into the potential environmental impacts of this project. The development of a major highway has other negative externalities as well, including decreased air quality (already a major health concern along the Wasatch Front), impacts to water quality, increased urban sprawl and development, and negative impacts to other birds, wildlife, and vegetation around Farmington Bay.

After I submitted my thesis, I developed a short summary of my work and recommendations based on my findings, which I sent to local stakeholders including contacts at the Wasatch Front Regional Council, the Utah Department of Transportation, the Governor’s office, and the Salt Lake City Council, among others. In this document, I recommended that local planners and policy makers rethink the location of the West Davis Corridor, or entirely rethink the necessity of constructing a new major highway. Though western cities are typically designed and laid out to accommodate cars, the Wasatch Front could be one of the shining examples of an area that is thoughtfully developed to maintain its natural amenities while promoting modes of public and alternative transportation. I also recommended promoting mixed-use developments (that is, commercial and residential development in close proximity) so people can live closer to where they bank, shop, go to school, eat, and so on. Mixed-use developments are also one of the key principles of the Wasatch Choices 2040 Regional Vision.

I never heard back from any planners or policy makers. Last year, I checked in with one of the planners at the Wasatch Front Regional Council about my recommendations. They acknowledged that it would be better for both wildlife and people to invest in alternative and public modes of transportation, but that the majority of Utahns do not currently support that investment. Since my thesis, the Wasatch Choices Regional Vision has been updated and looks to 2050 rather than 2040 and allows for greater urban and suburban development including more roads and other infrastructure to further promote economic growth with less mixed-use developments.     

The result of my thesis is a conflict analysis that serves as a preliminary step in the bioregional planning method. Understanding where vulnerable, valuable resources are—such as groundwater recharge zones, culturally significant areas, or critical habitat for migratory birds—is a critical early step of the process. In the Wasatch Front, conflict analyses could also be used to assess how other significant resources, such as ungulates, furbearers, native or threatened vegetation, other bird guilds, pollinators, and even aquatic species might be impacted by future development projects. The bioregional planning method also calls for pairing resource assessments with analyses to identify areas suitable for other land uses, such as new neighborhoods, roads, or natural resource development. Bioregional planning is all about taking an active approach to creating a data-driven regional future that is 1) economically viable, 2) socially just, 3) environmentally sound, and 4) collaboratively agreed upon by varying social groups (both majorities and minorities). It is an ideal planning method to use in rapidly growing western cities and towns since we have so many unique and wonderful natural amenities to conserve.

Ultimately, the future of the Wasatch Front, and other western communities, is up to those who plan it today. While it may require more forethought, inclusivity, and creativity than the typical method of planning, bioregional planning offers a helpful framework for creating a future that holds true to what not only Utahans, but other westerners prize so highly: a sense of place and community, outdoor recreation, and clean air and water. Future generations of both people and animals will appreciate the steps and efforts we take today to conserve our natural resources and develop in a sustainable and mindful fashion.

Aubin Douglas is a cartographer for the Division of Realty in the US Fish and Wildlife Service in Lakewood, Colorado. She has an MS in bioregional planning and is completing a second MS in ecology through the Department of Watershed Science at Utah State University.

The findings and conclusions in this article are those of the author and do not represent the official views of the US Fish and Wildlife Service.

Additional Reading

Douglas, Aubin A., “Conflicts Abound: How Future Development Along the Wasatch Front Will Replace Critical Migratory Bird Habitat Around Farmington Bay” (2018). Landscape Architecture and Environmental Planning Student Research. Paper 1.

Utah State University, “Moab Futures: A Bioregional Planning Analysis” (2017). Bioregional Planning Studio Reports. 2.

The Wasatch Choices 2040: A Four-County Land-Use and Transportation Plan.

Perspective From Corinna Riginos

Roads may well be humankind’s greatest source of metaphors, inspiration for a plethora of phrases about journeys and all the bumps, bends, twists, and turns along them. Even the word metaphor here is a play on words, because a metaphor means, literally, a transportation. Roads are, indeed, our greatest source of transportation, conduits for the movement of goods, the physical movement of people and culture, and the journeys within our souls they so often bring about.

Now let’s imagine that other species have roads just as important to them as ours are to us, only we can’t easily see them. Let’s re-visualize a map of the West that has not just our human interstates and highways, but also the scores of regular animal movement paths overlapping and intersecting them. Recent studies using GPS collars show us the deer and pronghorn highways that entire herds use to migrate from their winter to summer ranges and back. Their highways intersect ours and continue on through landscapes most of us will never see, because our human roads do not go there. We may not see these paths, but for deer they are just as vital as our roads are to us.

When we visualize it this way, it begs us to ask: how do we manage the flow of traffic at these junctions? This is the question we need to answer in order to address the problem of roads for animals and people.

Roads have two major impacts on wildlife. The first is easy to see and understand: vehicles hit wildlife on roads, killing them, injuring people, and damaging vehicles. We have estimates of the costs of these collisions: $50 million per year in Wyoming, alone.

Yet, it is the second problem, more difficult to measure and see, that is a greater concern for our wildlife: roads create a connection challenge for entire networks of animal paths. In a study I recently completed, I found that mule deer need at least 30 seconds between consecutive vehicles to get across highways. When there are too many vehicles, too close together, deer give up their attempts to cross. That means that for many hours of the day, on many roads in the West, animals cannot get to their habitat on the other side. Major highways can even be a total barrier; we see this in animal movement paths, as hundred-mile journeys abruptly dead end when they reach the most heavily trafficked roads.

Here in Wyoming, we are starting to make some progress on the problem. Scientists are working extensively to map big game movement routes and share the stories of the animals that traverse them. This storytelling makes animals’ journeys, with all their twists and bends in the road (real or metaphoric), relatable to people. We have mapped the areas with high numbers of wildlife-vehicle collisions and used economic analyses to show the monetary benefits of fixing those spots with wildlife crossing structures. We have built a number of these highway under- and overpasses and seen that they dramatically reduce collisions, allow animals to move back and forth across roads, and save more money—in terms of collisions avoided—than they cost to build. We have used the science and stories of migration and collisions to bring together diverse stakeholders, leading to a statewide strategy on roads and wildlife and millions of dollars in new funding to ensure safer passages.

Yet, there is more we could do. We place high cultural and economic value on keeping abundant herds of big game in the West, but we lack a way to express the value of the free movement that sustains these herds—or, conversely, what we lose in animals and dollars by cutting out their movements with obstructions like roads. Putting numbers to these ideas is difficult and even controversial, but it could open opportunities to further justify the benefits of crossing structures, or other fixes, to humans and wildlife. My hunch is that the economic value of sustaining migrations is substantial, and that defining this value would increase the range of funding options and tools for keeping these wildlife highways open.

Even without hard quantification, we could do a better job of valuing animal movements and the role they play in keeping our wildlife healthy and abundant. Imagine our human world without roads and travel. The pandemic has given us a glimpse of this, and we don’t like it. Our lives are less rich—literally and metaphorically—without our roads. The same can be said for our wildlife. Let’s ensure we can all continue our journeys, on all of our roads.

Corinna Riginos is the Director of Science for The Nature Conservancy in Wyoming and an adjunct associate professor at the University of Wyoming. She has been studying roads and wildlife and working with agencies on this issue since 2012.