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During spring migration, more than��half a million Sandhill Cranes visit the shores of Nebraska’s Platte River, a critical stopover where the species has roosted . But for some unlucky birds, this ancient place of respite is a modern deathtrap. Every year, dozens to many hundreds of cranes suffer deadly collisions with two electrical transmission lines that cross the river at ̽����ѡ’s .

Now a biologist has landed on a new method that seems to slash crane fatalities at the property. If his results, published in����������The Condor: Ornithological Applications, can be expanded to other sites, the technology would offer a new way for the industry to address a hazard that�� in the United States alone.��

James Dwyer, a scientist who helps electric utilities build more avian-friendly infrastructure,��embarked on the research because he saw that a key practice for trying to prevent accidents—the use of reflective, glow-in-the-dark, or other kinds of markers on the wires—wasn’t worth much when the sun went down.��“It was clear to me that the industry standard was not having a sufficient effect,” he says.��

With engineering colleagues at , the utility-technology company where he works, Dwyer��developed what he dubbed an “avian-collision-avoidance system.”��But while��its��name may sound better suited to a high-end jet, the system is actually rather simple; it's a��solar-powered device��fitted with��ultraviolet lights��that, when mounted on transmission poles, shine��on the wires. The goal: Make the lines��more visible to birds, while trying to avoid light pollution complaints from neighbors. “We went with UV light because birds can see it and people can’t,” Dwyer says.��

Though he wasn’t certain that Sandhill Cranes could see the shorter light waves, more studies are showing a wide range of birds—from storks and puffins to loons and owls—have eye structures that detect violet or ultraviolet frequencies. Based on this, Dwyer launched��forward with the experiment in spring of 2018. The��results exceeded��his expectations.

After the utility, Dawson Public Power, gave the go-ahead to test the system at Rowe Sanctuary, a technician monitored a single��850-foot span of power line on the property for 19��nights with the UV lights turned on and 19 with them switched off.

In the study, the team��reported that the Sandhill Crane collision tally dropped from 48 in the nights without UV lights to only one with them. What’s more, the number of “dangerous flights”—instances when a flock approached near the line and didn't stop or swerve—also decreased by 82 percent, from 217 to 39. The researchers��also noticed that more birds changed their flight path from��at least 80 feet away from the line, giving them clearance room to avoid a brush with death.

At Rowe,��the power lines are already fitted with colorful coils and hanging tags that have��reduced some crane fatalities—so many��collisions today occur either in foggy weather or at night. Sanctuary conservation director Andrew Pierson was impressed by the new��results.��“It seems quite positive,"��he says. "It seems like it worked."��

Sanctuary staff are already in ongoing conversations��with Dawson Public Power about options for reducing crane deaths, including bigger steps like��burying the lines underground or redirecting them to a less sensitive location. If the new collision-avoidance technology becomes available, Pierson is optimistic the utility will consider it. He��notes that it could also help Whooping Cranes, which face similar��risks while passing through the Platte habitat.

“[The utility]��is worried about collisions, too, especially collisions regarding an endangered, listed species. This represents a fairly cheap opportunity,” he says.��

While the results are promising and offer��a new preventative approach, more testing is required to demonstrate that UV lights��work��broadly for other birds and sites, says Richard Loughery, director of environmental activities at the Edison Electric Institute.��He helps coordinate the��, an industry collaboration with wildlife and conservation managers that funds research, works on siting issues, and publishes protocols for avoiding bird��collisions and electrocution. The Aldo Leopold Foundation, for example, turned to these guidelines��to win strong preventative measures—including lower towers and use of line markers—on a new transmission project��near its Leopold-Pine Island Important Bird Area in Wisconsin, says the organization’s conservation director Steve Swenson.��

Another open question is whether��UV lights can be a substitute for��line markers,��or whether the two methods need to be paired up, like in Dwyer's study. Installation of line markers can require a helicopter, so it isn’t always cheap or easy, Dwyer says. Less expensive��options, such as��the UV lights, could lower the bar for utilities to monitor and��protect more birds at a wider range of sites than they do today. That’s the upshot that Dwyer is striving for:��"It can solve both the biology problem and the industry problem."��