Predators want to eat you. Your habitats are disappearing. And some species that weigh less than an ounce travel thousands of miles from as far away as South America.
It’s tough out there for a migrating bird.
“They don't have maps. They don't know where the next food source is. They don't know where the next risks are. And so they're particularly vulnerable in a new place on a long journey,” said Joelle Gehring, a biologist with the U.S. Fish and Wildlife Service’s Migratory Bird Program.
One of the biggest threats are windows, she said. Scientists estimate nearly one billion birds in the U.S. collide with windows each year. At Zion National Park, however, one solution to this problem is making its way onto more glass.
Outside the Zion Human History Museum, park biologist Adam Reimer pressed a roll of contact paper against a floor-to-ceiling window near the front door. He peeled the backing off slowly to reveal a matrix of small dots spaced a couple of inches apart.
For songbirds that see ultraviolet light, the stickers show up as pink and black spots, sending the message that this window is not a place to fly through. For humans enjoying views from inside the museum, however, the dots are hardly noticeable.
“When we're looking at 4,000-foot cliffs (and) 2,000-foot cliffs surrounding this entire canyon, we don't want to take that away from anybody, whether you're inside or outside. But … we want to protect our birds as well,” Reimer said.
Birds take the world around them very literally, he said. So if they see something that looks like habitat — such as the reflection of a tree in a glass window — they’ll try to fly through it. Birds also rarely look forward because they’re scanning the periphery for predators.
“So even something that's very obvious to us isn't as obvious to a bird that's flying at high speeds and is looking off to the side.”
On top of that, habitat loss and other stressors have already shrunk North American bird populations by nearly 3 billion since 1970.
“Birds have been suffering declines over the last 50 years, and the window threat is right up there with the top threats to bird populations.”
Zion has roughly 300 species of birds throughout the park, Reimer said, including warblers, finches and the endangered southwestern willow flycatcher. The park has recorded around 30 bird collisions with its windows since 2017, he said, which is when the park began looking into solutions.
It installed its first window treatments in 2020 — decals that look like a silhouette of a hawk — but those haven’t proven effective. Newer iterations, like the UV dots, have shown to be better at preventing bird strikes in scientific studies, such as tunnel tests run by the American Bird Conservancy.
While the park may be more known for its wide open spaces than its buildings, there’s still plenty of glass here — around 18,000 square feet, Reimer said. To date, the park has applied the new film to less than half of it but aims to eventually cover every window. Next up, he said, may be the Zion Canyon visitor center.
“We plan to get the entire park treated, if we can. The goal would be to have zero bird strikes.”
The spring migration season, which peaks in early May in Utah, is an especially vulnerable time for birds. Many travel at night and can be attracted to community lights, which often leads to more glass strikes — a big problem, Gehring said.
“These are not the common birds that you might see in urban environments, but these are birds that are already declining.”
That’s why the USFWS has been retrofitting the windows of some of its buildings, too. In addition to UV dots, some have treated windows with solid patterns that look like bus wrap. Others have white dots that are visible to the naked eye to help raptors and other birds that don’t see UV light.
And for people interested in making their homes more bird-friendly, there are a variety of options to choose from.
Beyond the dots, applying anything from washable finger paint to soap on a window can help. You can also hang cords to create a bird curtain. In a moment of panic, she said, she once smeared toothpaste on the outside of a garage window that had been attracting birds, and it worked for years.
No matter what you apply, she said, the important thing is that it’s on the exterior and the design leaves no more than two inches of space — otherwise, small birds will believe they can fly through it. Reducing nighttime lighting around the house and closing curtains after dark can help, too.
“There are so many issues in the world, sometimes it can feel overwhelming. But these bird declines are something that we can all play a role in reversing.”
