Window strikes are deadly to birds around the world. What can humans do?

Editor’s note: This article is published through The Great Salt Lake Collaborative: A Solutions Journalism Initiative, a partnership of news, education and media organizations that aims to inform readers about the Great Salt Lake.

SALT LAKE CITY — According to Punita Koustubhan, the volunteer chair of the Great Salt Lake Audubon’s Bird Window Collision Working group, approximately one billion birds die from running into North America windows every year. 

Shorebirds, raptors and songbirds move through Utah during two primary migration seasons, which are March to May and Aug. to Oct. Per Koustubhan, those times are the most crucial to make sure windows are bird-safe. 

Buildings are one of the biggest threats to birds moving through populated areas.

“Their habitats have been changed. They’re really coming into our spaces, which used to evolutionarily be forest and other kinds of wild ecosystems,” Koustubhan said. ““We get these phenomenal migrations every year and Salt Lake City happens to be on the Pacific Flyway. So we get even more birds than a lot of other cities around us.” 

Since glass is reflective, birds often don’t realize they’re about to fly into it. Installing bird-friendly glass can be an option, although it is costly. 

There’s a cheaper, easier method: decorating glass with designs or films.

Koustubhan said bird tape is among the easiest and most affordable methods for making windows bird-friendly. 

“You can get different size sheets and have it be a do-it-yourself type of project,” Koustubhan said. “I experienced bird strikes at my home and I had my window washer put up bird tape after he did the cleaning.” 

Some companies also make building wraps, which can be applied to larger glass areas. 

Acopian curtains are another low-tech option. They’re made of small, barely-there strings that hang vertically in front of windows, signaling to birds that they can’t pass through the surface they cover. 

Looking to avoid making permanent changes due to window strikes? 

Acopian curtains can be removed after the migration season. However, there’s another, even cheaper option for those who may not be able to spend money on bird tape or curtains. 

“Grab some tempera paint [and]… just put up some temporary art on your windows. It can be very beautiful, too,” Koustubhan said. 

Another low-cost option that you likely already have? Bars of soap. 

“Sometimes bars of soap have been used, where you just put the lines up during migration season[s].” 

Regardless of the method you choose, Koustubhan said the most important factor is design spacing. 

Designs should be approximately two inches apart from one another, which is narrow enough that birds understand they can’t fly through it. 

“As long as you start your next little art part on your window, if it’s two inches away from the last part … birds will actually see that they cannot fly through that,” Koustubhan said. “They have a lot of data and they’ve proven that this two-by-two spacing actually works. It deters about 95% of birds.”

How else can we make populated areas friendlier to birds?

Birds use the night sky for navigation. Modern cities produce a lot of night pollution, which can leave migrating birds at the greatest risk. 

“When they’re flying towards our cities and looking for places to nest, they’re getting disoriented by our city lights,” Koustubhan said. “They get really dizzy.” 

City planners, building managers and homeowners alike can make other simple changes, like ensuring lights face downward, adjusting lighting timers and opting for light sources that are 3,000 Kelvin or less. 

Night skies are also beneficial to human health. They help our bodies regulate their sleep-wake cycles. 

“This isn’t just about protecting animals, but it’s about creating an environment that is beneficial for our own health and mental health,” Koustubhan said.