Project Safe Flight Points the Way to a Bird-friendly Future

The glass-clad buildings of the World Trade Center area are particularly deadly for migrating birds. Photo: Tod Winston


This article appears in the winter 2022-2023 issue of The Urban Audubon.

By Suzanne Charlé

Upon finding a dead Common Yellowthroat on a busy downtown Manhattan sidewalk in April 1997, NYC Bird Alliance member Rebekah Creshkoff was moved—and puzzled. “Apart from canaries,” she recalls, “I had never seen such a yellow bird and had no idea they even existed in New York City. How had it come to be dead on a sidewalk at the bottom of this concrete canyon?” Before long, Rebekah began circling buildings in the World Trade Center area every morning at 5:45, looking for window collision victims. Working alone, over the course of the year, she found 413 casualties. Soon afterwards, three other volunteers—Ned Boyajian, Kellie Quiñones, and Allison Sloan—joined her. NYC Bird Alliance’s Project Safe Flight was born.

Based on 25 years of research data collected by scores of Project Safe Flight volunteers since those first discoveries, NYC Bird Alliance estimates that nearly a quarter million migrating birds are killed annually in New York City in collisions with window glass. Birds do not perceive glass as a barrier, and collide at full speed when they attempt to fly into reflected habitat or sky. Artificial light at night is thought to be an important contributing factor to the problem, as it can draw nocturnal migrants into densely built areas where they are more likely to suffer window strikes. As our understanding of the magnitude of these threats has grown, Project Safe Flight has evolved to meet them.

Expanding across New York City and the Globe

Since Rebekah’s first patrol, the number of community science volunteers who monitor bird casualties during spring and fall migration has grown exponentially, as has the scope of the program. For the first time this fall, volunteers monitored routes in all five boroughs of the City. Routes were identified both through reports by NYC Bird Alliance members and local birders and from bird mortality data collected via NYC Bird Alliance’s crowd-sourced, online database, (As a result, these routes monitor just a sampling of collision-prone buildings; there are likely many other dangerous sites we haven’t yet identified.) As they patrol, monitors record the species and location of each dead or injured bird found. (The injured are taken to licensed rehabilitators; learn more about how another set of dedicated volunteers helps with that effort.)

Though progress is being made, we are far from our goal of a bird-safe city: this past October 23, 22 dead birds were found by World Trade Center buildings, including the pictured eight Yellow-rumped Warblers, two Black-throated Blue Warblers, two White-throated Sparrows, Ruby-crowned Kinglet, Palm Warbler, and Swamp Sparrow. Photo: Melissa Breyer

Manhattan, with its hundreds of glass-clad skyscrapers, is home to seven routes, including one in Times Square added this year. Volunteers in Brooklyn and Queens monitor one route in each borough. In Staten Island, NYC Bird Alliance Community Science and Outreach Manager Katherine Chen decided to focus on the St. George Ferry Terminal and the café at 1 Richmond Terrace, a potentially dangerous place for birds: “Large windows there reflect green areas where birds stop to rest and refuel.”
In the Bronx, five volunteers walk a route past two glass-clad Albert Einstein College of Medicine buildings. And the volunteers who do all the legwork? This fall, collision monitoring was carried out by a record 73 monitors, including 43 new recruits. This expansion of both routes and volunteers has increased NYC Bird Alliance’s ability to identify problematic buildings, and has also connected us with new communities across the City—getting residents invested in the birds that visit their neighborhoods. (, in the meantime, is now used by 62 organizations around the world.)

Making the City Safer, One Building at a Time

Armed with 25 years of Project Safe Flight data, NYC Bird Alliance is increasingly able to bring the owners of problematic buildings to the table to find bird-friendly solutions. Success stories are useful, as well: After Manhattan’s Javits Center replaced its glass façade with bird-safe alternatives in 2014, NYC Bird Alliance’s monitoring demonstrated a 90 percent reduction in collisions, according to Dustin Partridge, PhD, NYC Bird Alliance’s director of conservation and science. “Today, Javits is one of the City’s most bird-friendly buildings.”

  • This past summer, 1 Hotel Brooklyn Bridge, made aware of the bird deaths caused by its glass windows facing Brooklyn Bridge Park, installed Feather Friendly bird-safe film on a significant portion of its façade. 
  • In the World Trade Center area, Brookfield Place recently installed BirdDivert, a ultraviolet-light-reflecting film, on its glass-clad Liberty Street Bridge and eliminated artificial light at two high-collision parts of the building. 
  • Brookfield Place may have been encouraged by the installation last year of Feather Friendly on the deadly glass railing of nearby Liberty Park, which reduced collisions there.
  • In midtown Manhattan, the KPMG New York building, a frequent location of bird-collision deaths, made its internal lighting motion-activated, reducing light during the height of spring and fall migration.

NYC Bird Alliance continues to monitor these sites even after bird-friendly measures are taken, to ascertain whether bird deaths have actually declined. Early results are promising, and we hope to report findings in future issues of The Urban Audubon.

At left, the greenery-facing windows of 1 Hotel Brooklyn Bridge were treated with Feather Friendly bird-safe film. The dots on such window treatments must be spaced closely enough that birds perceive an impenetrable barrier.  At right, the ultraviolet-light-reflecting dots of BirdDivert bird-safe film are just visible on the windows of Brookfield Place’s Liberty Street bridge. Over time, our monitoring will reveal the effectiveness of this method.

Using Project Safe Flight Data to Enact Systemic Change

Given the sheer acreage of glass façades in New York City, the fight to make its buildings more bird-friendly also requires a “top-down” approach: legislation. In 2019, NYC Bird Alliance led a coalition of partners advocating in favor of the City’s landmark bird-friendly building design legislation, Local Law 15. Our Javits Center collision-monitoring data provided critical scientific evidence justifying the need for the law, which now requires that all new construction and significantly altered buildings use bird-safe materials. Soon to follow, research from NYC Bird Alliance’s annual monitoring of the Tribute in Light supported passage in December 2021 of Lights Out Laws Int. 271 and Int. 274, which require that all City-owned buildings turn out nonessential outdoor lighting and use occupancy sensors during peak migration.

As a recognized leader in the field, NYC Bird Alliance shares best practices on collision monitoring, outreach, building consultations, advocacy, and legislation with other cities around the nation. But our successes here at home are just the beginning. More must be done, and at a larger scale. In New York City, we are working with partners to shape new Lights Out Legislation that applies to privately owned buildings, as well as legislation that addresses preexisting bird-killing glass. And New York State has taken up the fight as well. In collaboration with Audubon New York, we are advocating for passage of a statewide Lights Out bill, the Dark Skies Protection Act. (Learn more about those bills here.)

“Project Safe Flight transforms the senseless death of individual birds into valuable research data that we use to advocate for bird-saving building retrofits and legislative change,” says Dr. Partridge. “We have a long way to go before New York City’s buildings are truly bird-friendly, but by continuing to support legislative change with scientific findings, we will get closer to the bird-friendly future we all wish to see.”

Learn more about Project Safe Flight.