Courtesy of Viveca Morris

As millions of birds fly north for their annual spring migration, some of the birds’ journeys will be stopped short on their way through New Haven as they collide into large glass windows, fall to the ground and die.

Birds have crashed into windows across the University and the Elm City for years, with the Yale School of Management’s Evans Hall being a prime example of a reflective glass structure that birds have trouble recognizing. University affiliates have recently collected data about the collisions at the school, with one estimate revealing that an average of three birds per day struck SOM’s windows in the spring of 2014. But the problem is not confined to Evans Hall, or even to the Elm City: The American Bird Conservancy estimates that over 1 billion birds are killed in North America every year due to these collisions.

“Bird-window collisions are one of the leading causes of bird loss in North America,” Executive Director of the Law, Ethics and Animals Program at the Yale Law School Viveca Morris ’15 ENV ’18 SOM ’19 said. “One billion birds per year killed due to window strikes [is] a tragic number. But it’s also a completely solvable problem, unlike many other problems facing animals. We know exactly what needs to be done to fix it and we have the ability to do that … yet here at SOM the building is killing at least 100 birds per year.”

Collections Manager at the Peabody Museum of Natural History Kristof Zyskowski confirmed to the News that Evans Hall causes 100 bird fatalities per year. He said that in the past 10 years, Rosenkranz and Luce Halls have had eight fatalities, the Peabody Museum-Kline Geology Laboratory complex has had nine fatalities and the Osborn Memorial Laboratories building has had five fatalities. He highlighted that SOM remains the “biggest killer” of birds on campus.

Collisions happen when birds are unable to recognize the glass in front of them, either because it reflects the sky or because the glass is so transparent and the birds can see through to open space on the other side. As such, solutions implement various ways to make the glass more visible to birds, such as through reflective films or etched patterns, while trying to maintain as much of the view as possible.

Yale and New Haven have both initiated steps to mitigate bird collisions in new construction projects. However, both struggle with their approach for existing buildings because retrofits can be very costly. For example, SOM Director of Facilities Bob Saidi estimated in October that installing protective film at the School of Management would cost at least $560,000.

“Are the buildings on Yale’s campus problematic for birds? Absolutely,” Morris said. “But the problem is not limited to just Yale or to just a few buildings. I think it’s much bigger than that.”

The issue: Bird collisions across the University and the Elm City

According to Morris, the School of Management is a “particularly egregious” example of bird collisions because of its design. She said that a graduate student found 18 bird carcasses lying around the building in May 2020, and that she expects to see similar numbers this May.

In addition to the bird problem at Evans Hall, the Yale School of Architecture’s Rudolph Hall has noticed issues with bird collisions since last year. Associate Dean of the School of Architecture Phil Bernstein ’79 ARC ’83 said that numerous migratory birds crashed into a west-facing window on the seventh floor of Rudolph Hall last spring.

“We decided to do a small research project to see if that window — which appears to be the only one in our building with this issue — could be treated with a protective film that was architecturally appropriate and kept the birds from hitting it,” Bernstein wrote to the News. “Unfortunately, because of the configuration of Rudolph Hall, that window is eight stories in the air and there’s no easy way to reach it to apply the film. So we are currently looking at other options.”

Morris also said that the newly constructed Yale Science Building has killed a number of birds, and that Zyskowski has been collecting the carcasses of birds that have died crashing into its windows.

Zyskowski told the News he found nine window-strike casualties on the east side of the Yale Science Building in October, but that no dead birds have been found so far this spring.

In addition to University buildings, Morris explained that many buildings throughout New Haven that are “also problematic.” She pointed specifically to the former Alexion Pharmaceuticals Global Headquarters at 100 College St., the Consulate of Ecuador at 1 Church St. and the Knights of Columbus Tower at 1 Columbus Plaza as examples of existing buildings with windows that cause “alarming” numbers of bird collisions.

‘Could be more rigorous’: The University’s solution

Strategies to reduce bird collisions broadly fall into two categories: standards for new construction projects or retrofits for existing buildings.

Yale’s solution for new construction projects is included in the Yale University Design Standards, which outline building regulations for the University. According to Director of the Office of Sustainability Virginia Chapman ARC ’85, bird-friendly guidelines for new construction projects are “now integrated” into these standards, which were last updated on July 15, 2019 — after construction began on YSB.

“We have highlighted these concerns and worked with colleagues at Facilities Planning to develop bird safe standards for all new building construction and renovation projects at Yale,” Chapman wrote in an email to the News. “It connects to the concern that our activities (in this case our buildings) have a negative impact on the environment, specifically biodiversity.”

According to the standards, the University seeks to increase the visibility of glass and dampen any reflections to reduce the appearance of a clear passage to the sky. The standards also call for reduced light pollution and fewer “bird traps” such as open pipes, ventilation grates and drains that may confine birds in enclosed spaces.

The standards acknowledge that bird collisions occur “often” at the University and that say that “mitigation is a concern.”

“[Chapman] and I were both recently on a call about how the University is going to implement monitoring, and has adopted all sorts of bird-safe design practices,” Morris said. “So it’s definitely working to some extent and it’s wonderful that Yale did that. And the standards could be more rigorous.”

As for the University’s approach to existing buildings, Bernstein told the News that the School of Architecture has since closed the sunshade on the window that was causing problems. According to Bernstein, this “seems to have solved the issue” for the time being — although Morris pointed out that based on data, fall migrations are often much more deadly to birds than spring migrations.

Director of Facilities Operations at SOM Jill McSorley ’03 told the News that the School of Management is making progress toward finding a practical solution to the “distressing” problem.

“We are currently experimenting with window film for Evans Hall, and now have eight small samples of film on the Eastern windows of the building,” McSorely wrote in a statement to the News. “We are evaluating the effectiveness of these samples, and are in the process of obtaining larger samples for these windows. We hope to have those larger samples in place by the end of the fiscal year.”

McSorley also pointed out that the school kept its shades down during summer 2020, which increases visibility for birds, and that the school has reduced indoor lighting in the building since the beginning of the pandemic.

Still, Morris said that she expects there will be approximately 100 bird fatalities at Evans Hall this year. She expressed frustration with what she sees as the school’s lack of initiative for implementing a solution to save the birds.

“This is … a missed opportunity for the school to lead by example,” Morris wrote to the News. “Nearly 300 birds are known to have died due to [SOM’s] building in the last three years, and that number is likely a significant undercount. How many more birds have to die before action is taken?”

‘No other municipality in Connecticut’: New Haven’s unique solutions

Morris brought the bird collisions to the attention of New Haven City Planner Jaime Stein a few years ago. Stein has since spoken with ornithology experts and others to understand the issue and consider potential solutions. According to Stein, New Haven is the only city in Connecticut that has seriously explored solutions to bird collisions.

“It’s work that we like because it’s not super contentious,” Stein said. “Everyone wants to do things that will help birds.”

Stein explained that the city is currently working toward producing a recommendation outlining bird-safe features, which may eventually turn into an ordinance. The recommendation may include reflective or patterned treatments on the glass being used in windows to ensure that birds are able to perceive the glass. If you encounter any issues with birds, Rapid Birdproofing Auckland is the ideal solution to seek assistance and resolve the problem swiftly.

Additionally, Stein said the city hopes to recommend that materials in proposed developments must have a threat factor below 30. The American Bird Conservancy has developed a threat factor rating system that ranks materials on a scale of one to 100 on how bird-friendly they are. Lower scores indicate fewer bird collisions.

According to Morris, the American Bird Conservancy classifies materials with threat factors under 30 as being bird-friendly, meaning they reduce collisions by at least 50 percent. Morris added she thinks New Haven’s threshold is “good.”

Stein explained that these recommendations have almost entirely focused on new construction, rather than on retrofits for existing buildings. She added New Haven is generally unable to dictate design guidelines for private property, which limits the city’s reach.

“Basically, the jurisdiction to include bird safe design guidelines would have to come from the state,” Stein said. “The state of Connecticut has jurisdiction over the building codes. Each municipality doesn’t have the ability to tweak.”

As such, New Haven is unable to impose bird-friendly standards on the University because Yale buildings, such as Evans Hall, are privately owned by the University.

“It’s time for action,” Morris said. “The sooner that a solution is implemented, the more birds that will be saved. We have a lot of data now and I hope that can be translated into a solution sooner rather than later.”

At least 4,000 species of birds migrate regularly, according to the National Audubon Society.

Julia Brown served as University Editor on the Managing Board of 2023. Previously, she covered the University's graduate and professional schools as a staff reporter. She graduated cum laude from Yale University with a B.A. in Economics & Mathematics.