NYC Audubon and Riverside Park Conservancy | April 8, 2024

Torie Bolster entered the world of birding just last year, and, like many West Side birders this spring migration, she’s keeping her eyes open to spot Cuckoos, Flycatchers, Warblers, Tanagers, and Orioles inside Riverside Park—which could be considered her office. As Riverside Park Conservancy’s Conservation Crew Leader, and now leader of the RPC Birding Club, Bolster has prime access to the six-mile-long bird haven. 

Unfortunately, until very recently, Riverside Park struggled with a collision problem. Collisions are a leading cause of death for wild birds and kill an estimated one billion birds across the United States each year. Birds cannot perceive glass as a barrier, but rather see reflections of sky or surrounding vegetation before fatally striking a building’s windows. Like with so many buildings in New York City, birds were striking the windows of the Peter Jay Sharp Volunteer House in Riverside Park, meeting an early death. Because of these collisions, Torie Bolster began a concentrated collision route around the Volunteer House, where she’d find and discard dead birds.  

“My first time seeing a Fox Sparrow, it was dead,” said Bolster. “My first lifer and it was deceased.” 

The Riverside Park Volunteer House is a 100-year-old limestone building that sits rather majestically at the W. 107th block of the park. The second floor houses the Evelyn Sharp Meeting Room, the ambiance of which has been likened to that of a treehouse with panoramic windows of the surrounding tree canopy and Hudson River.
 

“It’s a beautiful building with those big glass windows,” said Nina Webb, a Riverside Park Conservancy Field Supervisor. “We love this building as people who can look out those windows. But it was always at a big cost.” 

Webb has volunteered for NYC Audubon’s Project Safe Flight for over two decades, as a collision monitor and one of the first 9/11 Memorial Tribute in Light monitors, and now as a member of the Injured Bird Transport team. While collision carnage was nothing new for Webb, it now became standard for Conservancy staff as well, who would receive updates on dead and injured birds in their work chat.

“During lunch, volunteers would hear birds bang against the windows,” shared Oliver Lopez, a Conservancy Gardener in the Riverside Park Bird Sanctuary, located nearby. 

Park Gardeners with the additional task of rescuing wildlife—like the occasional groundhog stuck in a fence or abandoned baby squirrel—would often arrive at the Volunteer House when it was too late to save any collision victims. 

“It’s been very stressful to see the birds completely and needlessly have these collisions,” said Webb. “We’ve been wanting this for a really long time, and it’s a tremendous relief.”  

Webb and Bolster decided the Conservancy could—and should—make a change on their home turf. They advocated for a bird-friendly retrofit, and in 2023, the Conservancy reached out to NYC Audubon to consult on the frequency of collisions at their Volunteer House and ask what could be done to make a change.  

Every spring and fall, millions of birds migrate through New York City, journeying along the “Atlantic Flyway” from wintering territory in South and Central America to breeding grounds as far north as the Arctic Circle. As this huge variety of birds—from songbirds to raptors, hummingbirds, and shorebirds—repeat their ancient cycle of migration, they encounter two relatively new threats: glass windows and artificial nighttime lighting. 

 

This encounter proves deadly: according to NYC Audubon’s research, between 90,000 and 230,000 of these migrating birds are killed in New York City each year due to collisions with building glass. Luckily, solutions do exist and can be implemented on a societal level—and also on an individual scale, like at Riverside Park.

“Because of all my experience with NYC Audubon, and reading and learning, I knew there was a solution that needed to be made. I was definitely one of the people who was—agitating to get it done,” Webb laughed. 

In early 2023, Dr. Dustin Partridge, NYC Audubon Director of Conservation and Science, and Katherine Chen, NYC Audubon Senior Manager of Community Science and Collision Reduction, visited Riverside Park to consult on the Volunteer House, assessing where the collisions occurred most often and explaining how the surrounding canopy made for perilous reflections for the birds. When assessing the risk of windows to birds, it’s important to remember that not all glass is equally hazardous, which is why documenting collisions is critical in finding effective solutions. 

After assessing the area, NYC Audubon suggested a complete retrofit of the Volunteer House windows. As the movement for bird-friendly design has grown, so too have the options for making windows bird-safe, from window screens to parachute cords, painted murals, window decals, and films. One of the most effective solutions is dotted films which can easily be applied in sheets to large windows like at the Volunteer House. With white dots separated at the golden ratio of two inches apart, the simple dots suddenly make the glass visible to birds, reducing damaging and fatal collisions. (Read about other NYC bird-friendly building retrofits here.)

Riverside Park Conservancy chose Feather Friendly, a Toronto-based company that offers commercial, residential, and even DIY installation options to help spread the solution for preventing bird collisions around the world. Installations are minimally obstructive, allowing humans to still fully see out windows while also ensuring the birds flying by recognize the windows and will not collide into them.

With a large crane just before the start of Spring, and in collaboration with Feather Friendly, the Conservancy successfully implemented bird-friendly window film at the Volunteer House in March 2024.

"When our team first brought my attention to the frequency of bird collisions at the Volunteer House, I understood the gravity of the situation, as well as the opportunity for us to be a leader in demonstrating safe alternatives,” said Merritt Birnbaum, President and CEO of Riverside Park Conservancy. “I suggested they reach out to the experts at NYC Audubon to find the best solution.” Birnbaum added, “While the cost of the bird-friendly retrofit was not insignificant, it’s an essential investment that fits squarely within our mission to repair, maintain, and improve Riverside Park. Protecting bird life isn't a secondary choice; it's integral to achieving a healthy and sustainable park ecosystem."

“I suspect this retrofit will help to protect some of the most vulnerable yet charismatic birds we have: Warblers,” said Partridge. Riverside Park is full of native trees and a developed canopy—something relatively rare in the City—and many Warblers rely on this type of habitat for foraging during spring migration. 

“The windows in the Volunteer House are near canopy level and presented a serious threat to warblers—that threat has now been removed,” said Partridge.

And the benefit isn’t only for the birds. “We hope this will be the start of passive and active programming around protecting wildlife,” says Bolster. Whether visitors notice the bird-friendly windows while on a jog, or a guide points them out during naturalist walks, Bolster hopes they’ll take notice and learn. 

“[The film] doesn’t detract from the beauty of the area, and even if you notice it, it’s such a great conversation starter.”

Nat Xu, a Conservancy Gardener often tasked with rescuing wildlife in Riverside Park, was one of the most excited on staff to see the retrofit completed. “[The Volunteer House] is so embedded in the wildlife and trees around here. It’s a central hub, and having this be a park initiative is amazing. It gives me some relief that the birds will be safe.”   

Originally from Wisconsin, Xu previously pressured the City of Madison Plan Commission to build with bird-safe glass. “When you can make a change, like making a building bird-safe, it seems like a no-brainer to protect these animals,” they said.

In the modern age, as we think about bird-friendly design, we often think of daunting NYC skyscrapers and green infrastructure solutions like bird-safe glass and green roofs. But human beings share the planet with millions of other species. Over our time here on earth, we have altered ecosystems—and thus, the lives and evolutionary trajectories of countless other species—in extraordinary ways. From filling waterways and paving over land, building enormous highways and buildings, and constructing underground railways and sewer systems, the aggressive development of urban landscapes has resulted in extreme alterations and disruption to ecological processes. The abundance of reflective windows and perilous glass is only part of that story.

“Habitat fragmentation” is exactly what it sounds like. Urban planning choices have resulted in isolated pockets of green and blue spaces, which become separated by impervious surfaces, busy roads, and built structures. This lack of connection—and, in New York City, the alarmingly compromised conditions of these areas—results in hindered ability for wildlife to access food or shelter. This fragmentation can also limit the gene pool of a species, which causes more vulnerability to disease and less ability for future generations to evolve and adapt to changing environments over time. 

When offered the dignity of adequate investment and holistic stewardship practices, New York City’s urban parks and waterfronts hold incredible resilience and potential to function in harmony with humans while supporting biodiversity and healthy habitats. Riverside Park is a prime example of a waterfront park that plays a key role in the lives and survival of birds and other wildlife. 

Situated along the Hudson River, the Park spans from 59th St. to 181st St. but is also part of the Atlantic Flyway. Every year birds migrate up and down this flyway following food sources, breeding grounds, or traveling to overwintering sites. Riverside Park plays an important role in this migratory journey as a landscape that provides extensive forest edges and lawn spaces for birds to eat, drink, bathe, and rest. The bird-friendly glass at the Volunteer House, while an incredibly important investment for New York City wild birds, is only a part of the larger picture to maintain biodiversity and support conservation for Riverside Park Conservancy. 

As a haven for a variety of bird species—including Red-Tailed Hawks, Owls, Warblers, and many additional flying creatures—the Conservancy sets an example for other parks and green space managers in NYC because threat reduction, like making windows bird-safe, should always go along with habitat improvement, installation, or management in urban areas. Some examples of this urban green management include The Bird Sanctuary, located in the Forever Wild Forest at approximately 120th Street and Riverside Drive, which features a man-made water source fondly known as The Drip, a critical feature in Manhattan where most natural water sources have been paved over. The Conservancy also worked with The Neighborhood Cat Rescue to reduce the feral cat population, in addition to implementing native plant species to help rebuild critical wildlife habitat. 

“Riverside Park Conservancy takes sustainability and conservation seriously,” said Dr. Partridge, NYC Audubon. “The views from the Volunteer House are now a powerful example demonstrating that bird-safe design does not detract from a view, rather, it provides a safe way to share a green space with the wildlife that make the views so great.” 

As the Conservancy continues to take steps to protect bird populations, we also encourage individuals to investigate ways they can make their homes and communities more bird-friendly. Protect birds and bird habitat in your neighborhood by adding native plants to your garden. To help reduce collisions, report dead and injured birds to dBird.org and help build NYC Audubon’s dataset to make systematic changes to help build a bird-safe City. If you see an injured bird, please bring it to the Wild Bird Fund, or keep it contained before reaching out to injuredbird@nycaudubon.org. Turn off your lights during migration season (April - June, August - November). And most importantly, speak up and work to make a change!


_{Looking to get involved with New York City’s birding community and learn more about flying wildlife in the Park and beyond? We invite you to join RPC Conservancy team members, Torie Bolster and Marcus Carceres, who lead free, monthly birding walks at our Birding Club, in addition to the hundreds of NYC Audubon bird outings that take place across all five boroughs, most of which are free.}

From 59th Street to 181st Street, from riverfront to city-side, Riverside Park Conservancy cares for and enhances six miles of parkland for present and future generations. Working together with the New York City Parks Department, we make improvements as diverse as the park itself and the city it serves.

New York City Audubon is a grassroots community that works for the protection of wild birds and habitat, improving the quality of life for all New Yorkers. For 45 years, NYC Audubon has championed nature in the City’s five boroughs through a combination of engagement, advocacy, and conservation. Through these efforts, we protect the more than 300 species of birds living in the 30,000 acres of wetlands, forests, and grasslands of New York City.