An American robin encounters one of the many oddities of the manmade environment: glass windows. Credit: Wildlife World

By Eva Bein


When I met up with University of Illinois senior Colin Dobson one morning in Fall 2021, he greeted me with a smile, a camera around his neck, and a Target bag full of dead birds.

Let’s backtrack.

No, Colin isn’t a serial bird killer or obsessive taxidermist — he’s a birder conducting research.

Ornithology is the official name for bird science, while “birders” are hobbyists who observe or identify birds in their natural habitat. Ornithologists rely on birders in the field. After spending time with Colin during his bird collection walks, a twice-daily routine where he collects data for a bird strike survey on the University of Illinois campus, I’ve come to know birders as an enthusiastic community with an unparalleled appreciation for the natural world.

As I ventured into the Engineering Quad, the early morning sun was bright against buildings lined with clean, long, reflective windows. The U of I campus offers a perfect example of why cities are major death zones for migrating birds. Birds get confused by the reflective glass and light from windows and accidentally strike them mid-flight, causing over 1 billion bird deaths a year in the U.S and contributing to declining avian populations. The weight of that number of dead birds is comparable to 550 loaded coach buses.

The ghostly imprint of a mourning dove on a window after a collision. Credit: Portland Audubon

While humans tend to avoid windows better than birds, window strikes aren’t an act of stupidity by birds. In fact, whether birds are migrating 500 miles, like the ruby-throated hummingbird, or more than 25,000, like the arctic tern, birds are quite smart and know exactly where they’re going. They have their own GPS system called “internal magnetic focus.” Their eyes work as the compass as they physically see the direction of the magnetic field on the Earth, while magnetic material in their beak acts as the map that shows the strength of the field, leading them in the right direction. Their eyes can adjust to light twice as fast as a 20-year-old human, and they rapidly adjust the lens to zoom in and out while navigating or searching for prey.

Bird strikes generally stem from two reasons out of birds’ control: glass reflections and light confusion. Windows reflect trees, sky, and other vegetation nearby, making it hard for a bird to distinguish what is real and what is simply a reflection of its surroundings. Clear glass also causes collisions if a bird is simply trying to reach the landscape on the other side. When the sun goes down, birds flying at night encounter a different host of problems. Birds navigating in the dark depend on celestial cues, such as stars, along with their internal GPS system. With streetlamps, lit-up buildings, and other light pollution invading their vision, birds end up confusing their cues and colliding with buildings. The American Bird Conservancy shows how common bird strikes are in any area, not just those with tall buildings. According to its website, “when people first learn about glass collisions, many assume that brightly lit skyscrapers at night pose a special threat. However, most collisions take place during the day, and almost half occur at home windows; low-rise buildings account for almost all of the rest.”

Of course, bird strikes are not the only cause of the decline in bird populations. Cats remain one of the biggest causes of death, proving the classic cat and bird arch-nemesis theory correct. The U.S. Fish and Wildlife Service notes that habitat loss poses the next biggest threat, while getting hit by cars, running into wind turbines and electrical wires, and poison from fertilizers and other chemicals likewise contribute to the mortality numbers.

The Beckman Institute’s numerous reflective windows make the campus building a hotspot for bird strikes. Credit: Eva Bein

Back on campus, the biggest threat to birds appears to be some of the U of I’s newer buildings: the Gies College of Business Instructional Facility and the Beckman Institute, to name two. A common trait of these buildings? Clean, long, reflective windows. 

The GEEB Bird Strike Survey that Colin is working on originated in 2019 from Integrative Biology graduate students who were also in ecology and evolutionary biology fields, or GEEB. These students launched their project out of curiosity for which buildings were most harmful to birds and which birds were striking buildings the most. Colin, majoring in Natural Resources and Environmental Sciences, took over a few seasons later. During the Fall 2021 data collection, over 200 birds were found along the main campus routes, creating an average of more than 1,000 noted dead birds over the past five seasons. During fall and spring, when birds are migrating, volunteers conduct counts twice a day across campus to collect data. Results have already shown that fall migration leads to more strikes than the spring, and that birds are more likely to strike windows in the direction from which they’re migrating.

When I finally connected with Colin — camera, bird bag, and all — we walked the perimeter of each building on the campus route, scanning the ground for any fatalities. To an unsuspecting student strolling through campus, this data collection can be quite a sight. Colin told a story about being seen holding seven Ziplock bags of dead birds. “I was definitely getting looks,” he laughed.

While it sounds odd, bagging dead birds provides valuable data on what local and migrating populations look like during this snapshot of time. This type of information is especially important with our changing climate. With an unpredictable future ahead, this data will prove valuable to scientists looking to make comparisons to the early 21st century.

As we circled Grainger Library, I soon spotted a small blob on the ground followed by an uneasy rush of excitement.

We’d found our first bird.

Colin gently scooped up the northern parula, turning it over to examine its different features, and explained how the blue and yellow coloring clued him in to what species it was. A few feet away lay a yellow feathered golden crowned kinglet that was less than half the length of my ballpoint pen and looked only a few inches wide. For both birds, Colin logged the information: date, route, time of day, building, and direction the window faces. As we went through the routine data collection process, I felt an interesting mix of emotions. It was sad to see the death of such delicate creatures; yet these feelings were mixed with the scientific drive of the data collection. “Yeah,” Colin grimaced with a downward glance. “It does get pretty sad. We’ve collected up to 33 birds in a single day.” Whether these birds are traveling from places like Peru, Argentina, or the Caribbean, Champaign is where their migration journey prematurely ends.

A golden crowned kinglet found on the Window Strike Survey. Credit: Eva Bein

We headed toward the south side of campus with the sun above our heads, keeping our eyes glued to the perimeters of buildings along the way. Colin explained how they’ve logged 52 different species of dead birds just this past season, which sparked a conversation on just how many birds he’s actually seen and identified. As the president of the Champaign County’s Audubon Society, he’s observed birds in all 102 counties in Illinois and has even explored birding internationally. No matter what animal I thought of, from Canada Geese to tropical parrots fit to star in a Disney animation, Colin had a photo or adrenaline-filled bird chasing story to go along with it. He gave me the scoop on how expansive the birding community is, as well as how intense bird watching — and chasing — can truly get.

Colin’s passion for birds naturally led him to helping to protect them. The Bird Strike Survey’s goal is to raise awareness, collect data, and help with future architectural decisions and solutions when it comes to creating a bird-friendly campus. Colin explained that the survey has finally reached the ears of the Facilities & Services (F&S) administration on campus, who have inquired about the best ways to mitigate the problem. Adding glaze or footing to windows can be a way to add texture and signal to birds that something is there without the entire cost of replacing the windows. Turning off lights or adding blinds can also prevent unnecessary bird strikes. Colin stressed that, unfortunately, making changes to windows across campus will take large amounts of time, money, and energy, although based on his recent communications with F&S he does have hope that positive changes will take place.

Just before we ended our trek at 9:20 a.m., we catalogued our last fallen bird, a dark-eyed junco. Our route came to an end at the Natural History Building, where we delivered the birds to their freezer storage. I opened the door and came face to face with 300 bagged birds. We couldn’t help but dig through the different species as if it were a morbid prize bucket. Fascination trumped fear as I looked at these birds, to be preserved for years to come. While we only stood in the tiled hallway of the Natural History Building for a few minutes, I couldn’t help but feel like I was a part of a little piece of ornithological history in the making.

Birds are vital to our planet’s ecosystems, and they are icons of freedom and beauty across cultures; yet a birder’s appreciation of them goes a step beyond. For Colin, they hold an intrinsic value, worthy of appreciation regardless of their scientific value. That passion makes the unnecessary deaths of birds due to thoughtless building design particularly hard to swallow.

Bags of dead birds should not be the cost of this deep appreciation for ornithology. With some building fixes and progressive design approaches, we’ll be able to keep our bird watching up in the sky and the trees rather than directed to the ground. And we’ll save millions of birds in the process.

About the Author …

Eva Bein is from Wheaton, Ill., and will graduate in May 2023. She is majoring in Earth, Society and Environmental Sustainability and minoring in both Business and Journalism. She is excited to job search in the business world with a focus in sustainability and environmental communication.

This article was the grand prize winner in the 2022 Janelle Joseph Environmental Writing Contest.