Unseen Danger: One Day of Deadly Window Strikes for New York’s Birds

Go behind the scenes with the dedicated New Yorkers working to stop the flood of avoidable deaths that occur in the city each migration season.
A gray and yellow warbler lies dead on a sidewalk, feet up in the air, while people and cars pass by, the busy city in the background.
A dead Canada Warbler in Columbus Circle. Photo: Diana Cervantes

Every year, up to 230,000 birds meet an untimely death in New York City by colliding with building glass. During migration, artificial lights lure birds into the thick of the city, where they find themselves surrounded by a house of mirrors. Disoriented and exhausted, perhaps drawn to inviting vegetation reflected or framed by a window, they crash as they try to escape. 

At a national scale, these losses pile up: The U.S. Fish and Wildlife Service estimates that as many as 988 million birds die in building-glass collisions each year. That’s more than 3,000 times the death toll from collisions with wind turbines. Others say the annual total likely reaches 1 billion birds.

These deaths are especially troubling in our age of major declines in bird populations. They are also preventable. Design decisions, choices of construction materials, and bird-friendly treatments added to existing windows can reduce collisions. And as Lights Out programs around the country are finding, turning off nonessential lighting during migration keeps many birds out of harm’s way.

We wanted to better understand the building-collision problem and give readers a fuller sense of its impact. So, we used BirdCast, a migration forecasting tool created by the Cornell Lab of Ornithology, to choose a date when a flood of birds was expected to pass through the city. On May 16 we sent reporters and photographers out with volunteers from Project Safe Flight (PSF), an effort led by New York City Audubon to document birds that strike buildings and windows across the city during migration. We also dispatched a team to Wild Bird Fund (WBF), the Manhattan wildlife rehabilitation facility that takes in and treats injured birds brought to them by PSF volunteers and good Samaritans across the city. 

What follows are the scenes and stories of a single day of spring migration in New York. The dead and injured birds we encountered were among 62 individuals collected by PSF volunteers that week. The previous week, volunteers found 138 birds. But the program covers just 47 buildings and locates only a slim fraction of birds involved in collisions. What’s more, these incidents are much more common in the fall, when first-time migrants that hatched over the summer swell the number of migrants—and collisions.

City leaders have taken steps to address this problem, including a 2019 law that requires bird-safe building materials for new construction, and another in 2021 that directs city-owned buildings to shut off nonessential lighting during migration. Other cities and some states have passed similar measures recently. At the federal level, the Bird-Safe Buildings Act would require new or remodeled government buildings to use materials shown to reduce collisions. Congress has mulled the bill since 2010 but has not yet passed it.

For now, birds face innumerable perils as their ancient migration routes lead them through our cities and towns. Fortunately, they are helped along their way by caring people who do what they can to make their homes and workplaces safer, and by the dedicated professionals and volunteers who do their best to save those that fall.

Team Key:


World Trade Center


Columbus Circle


Wild Bird Fund

Midnight: A gentle breeze is blowing from the southwest. Riding this light tailwind, some 4,500 migrating birds are at this moment navigating the vast obstacle course that is Manhattan. Many have come thousands of miles already. Some have hundreds of miles to go before they reach their nesting grounds. All told, close to 230,000 birds will fly over or between the borough’s gauntlet of buildings on this night alone. Or try to.  


5:40: It’s a cool, 58-degree morning in Manhattan’s Financial District. A breeze is kicking off the Hudson River, swirling through the World Trade Center Complex. I’m here to meet Melissa Breyer, a volunteer for PSF. This area, with its gleaming glass towers, is particularly deadly. 

I’m a half-hour early to our meeting spot at 4 World Trade Center (4WTC), so I walk around the building by myself, scanning for dead or dazed birds. Joggers pass by in the dim morning light as, across the street, a maintenance man trims the shrubs around the 9/11 Memorial. Suddenly I see a small lump up ahead—a bird huddled in an alcove. My breath catches. An Ovenbird. It looks alive. It is alive! What do I do? Do I grab it? I approach slowly for a closer look, but it flits up to a nearby tree and disappears. Maybe it was just stunned. Maybe it’s okay. Maybe that’s a good sign for the day. 

6:00: I meet Breyer at the corner of 4WTC. This is her sixth season with PSF. She began during the pandemic in 2020 and has recently drawn attention to the issue of window strikes by documenting the birds she finds on Twitter. A few minutes later, photographer and fellow PSF volunteer Andrew Garn joins us. He’s holding a dead female Common Yellowthroat he just found alongside the building, the first official casualty of the day. 

As we begin walking her route, Breyer scans for birds. “I find them in the gutter sometimes. I find them in the street. I look all around,” she says. “A lot of times, after they hit, they’ll fly to a tree and then die. So, I’ll find them under trees a lot.” I’m suddenly less hopeful for my Ovenbird. 

At this point, she explains, we’re already a little late to find birds injured or killed overnight, since some building maintenance crews are already out cleaning the sidewalks. They’ve been coming out earlier and earlier, she says, which means that Breyer and other volunteers need to one-up them to get accurate counts. “It’s like an arms race,” she jokes drily. Last night’s huge flight at low altitude has Breyer thinking we could have a busy morning—most strikes happen below roughly 100 feet, where birds spend the most time foraging, and where glass reflects vegetation—but it’s always hard to say: “You can never predict.”

On the south side of 1WTC, we find the day’s second dead bird, a female Blackburnian Warbler on the sidewalk, her two white wing bars and butter-yellow head giving her away. Breyer puts the bird in a plastic bag, writing down the species, location, and time to keep track of each victim. 

Then, around the corner, we spot a male American Redstart under some trees. It’s alive but breathing heavily. “Don’t get too close,” Breyer cautions as she begins to approach. I hang back, but the bird is alert enough to dart to a tree above as she gets closer. Unable to retrieve it, we continue on to the north side of 1WTC, where we find a dead female American Redstart. 

6:15: I ask about the cleaning crews and doormen posted like sentries outside the buildings. Are they helpful or defensive? “They all vary,” Breyer says. “Some are really, really nice, and they care. I do think they aren’t really encouraged to help us.” They are also extremely sensitive about any photography of the building facades or workers. “Even one of the guys that I’m really tight with here doesn’t like me taking photos,” she says as we head to 7WTC.

6:24: Finding dead birds also requires looking up. Breyer carefully inspects any glass awnings—hefty, cantilevered structures above many building entryways—for the crumpled bodies of last night’s victims. On the north side of 7WTC we find a dead bird in the street. “Another yellowthroat. Female,” Breyer says. “You know what’s crazy, last week it was all males.” This could be a result of male birds migrating before females so they can stake out breeding territories.

Not 15 feet away lies another lifeless bird—a male Chestnut-sided Warbler, a gorgeous species considered a treat for birders. It has the unfortunate distinction of being Breyer’s first this season.

6:34: Foot traffic is increasing. The city is waking up. Madeleine Marrin, a first season PSF volunteer, has joined us. I ask her how she got involved. “I saw a birding account that I follow on Instagram posting about it, so I went to the info session,” she says. She wasn’t even a birder before that.

We’ve finished our first loop around Breyer’s route, so we head a few blocks south to Brookfield Place, a large, mixed-use complex directly on the riverfront. Brookfield is part of another PSF volunteer’s route, but Breyer is covering for them this morning. Walking along a landscaped divider separating the sidewalk from a bike lane, she scans the mulch and plants. “A lot of times, if people find a dead bird, they’ll put it in a planter.” 

As we approach Brookfield, Breyer points out the “unfortunate” scaffolding where part of the complex is being renovated. Wooden panels on top of the scaffolding often catch dazed or dead birds, preventing volunteers from collecting them. We go straight to a spot where Breyer regularly finds birds, but there are none today. Next, Breyer opens a door to the building’s main atrium. “We’re gonna go inside and peek on top of the scaffolding.” From a stairwell inside, we look out over the wood paneling. Nothing.

6:49: We’re back outside. The morning sun is starting to filter through downtown’s skyscrapers, their facades glinting against the clear blue sky. Breyer stops below a glass skywalk that bridges the street and connects two Brookfield buildings. Transparent dots have been applied to it to deter bird strikes. “This skywalk used to be really bad …” she says, her voice trailing off as something catches her attention. “There’s a bird across the street.” She cuts across the road in a flash. Sneaking up behind the bird “like a cat,” Breyer firmly but gently grabs it with a bander’s grip, securing the head between the pointer and middle fingers. “I wanted to get it before it flew,” she says as she places the male American Redstart in a paper bag, where it will remain until we can get it to Wild Bird Fund for treatment. “I could tell it was alive from over there.”

Meanwhile, around the corner, Marrin has found a Swamp Sparrow that wasn’t as lucky. Then, at the south end of Brookfield, we find another male Common Yellowthroat, dead.

7:02: “This stretch of Brookfield is pretty bad,” Breyer says. We’re entering the large waterfront plaza on the west side of the complex. Flanked by restaurants and bars, the area is also loaded with trees and lush sitting areas surrounded by shrubbery. From the greenery, the calls of a migrating Eastern Wood-Peewee and Northern Parula ring out. We don’t find any birds here this morning, but it’s easy to see why this area is so dangerous: What looks like great habitat to a travel-weary bird draws them into the disorienting cityscape and becomes a death trap.

7:07: We head toward 4WTC to run Breyer’s route again. “On busy days, I’ll do 12 miles,” she says. We don’t find anything on a second pass, which surprises Breyer. It’s a slow day for her, but still eye-opening to me.

7:21: This time, as we walk back to Brookfield, Breyer detours us along a median between West Street and a bike lane. As she weaves through conical cement barriers, she suddenly spots a female Common Yellowthroat, at least 50 feet from any building. The bird is on a sewer lid, smashed to smithereens after being run over by a bike. Breyer doesn’t always pick up a bird when it’s been destroyed this badly, but today she does. Her ability to find birds in surprising spots comes from experience. “I don’t think anyone would think to look over there,” she says about the bike lane. Passing a street cleaner hosing off the sidewalk, she motions toward the street. “This is why I check the curbs,” she says. “A lot of time, they’ll spray them off.”

7:27: From the street, Breyer points up to the glass railing running the length of Liberty Park, an elevated green space across the street from the tree-flanked memorial. Below the railing is a living wall loaded with plants. This glass barrier, invisible to birds flying between patches of vegetation, used to be another major hazard. “We’d just find birds all along here,” Breyer says. “Dozens of birds at a time.” After Breyer and others drew attention to the issue, the Port Authority of New York and New Jersey, which manages the park, applied Feather Friendly dots to the glass—save for 10 panels that were blocked by construction at the time, Breyer reports. As she shares this history, we spot a bird in the road below: a live Common Yellowthroat. It likely hit one of the dot-free panels. “I’m still finding birds at these 10 panels,” Breyer says.


7:32: Volunteers Laura Lincks and Alice Winkler arrive at 10 Columbus Circle, an enormous building whose glass facade curves along the traffic circle at the southwest corner of Central Park. To the trained eye, it’s an obvious high-risk building for bird collisions. Lincks, who monitored this site last fall, says she would sometimes find as many as seven dead or injured birds here in a day. Winkler brings along her regular patrolling partner, her eight-year-old terrier, Sawyer. “He gets an extra long walk on these days,” she says.

Lincks and Winkler immediately find a gorgeous gray-and-yellow bird on the sidewalk: a male Canada Warbler. “I guess that’s the closest I’ll ever get to one,” Lincks says. He’s tipped on his side with eyes cracked open and legs outstretched. The volunteers gently brush his legs. They’re stiff, and he doesn’t flinch, confirming he’s dead. Lincks wanted to be sure: A couple weeks ago she found a Louisiana Waterthrush at this exact spot that perked up when she got close. She was able to bring it to WBF for treatment. Although the work can be upsetting, Lincks says, “holding him in my hand for a few seconds and looking at him was actually very magical.”

As Lincks and Winkler observe and record the warbler, taking photos and noting his precise location, a couple of passersby stop for a moment. “The other day I found three dead birds in a row here,” one says, and asks what’s killing them. The volunteers explain about glass and reflections, and the passersby shake their heads. An off-duty security guard leaving the building notices the cluster of people and calls inside for the maintenance crew to dispose of the bird. 

Lincks and Winkler scan the sidewalks from the edge of the building to the gutter and look up at the glass awnings over the doors, where Winkler often spots dead birds on her patrols. Lincks is wearing binoculars around her neck to aid such an examination, if necessary, but the awnings are empty.


7:40: At the corner of Brookfield—the exact spot where we found the stunned American Redstart earlier—we now find a Common Yellowthroat, also alive. Breyer is also able to snag this bird. “A lot of the time they hold onto my finger, which is kind of heartbreaking,” Breyer says as she pulls her hand out of the bag after placing the yellowthroat inside. “Sometimes I put a little cloth in the bottom for them to hold onto.” Along with recording the location and species, she takes a picture of each recovered bird to have a time stamp. “I want the data to be perfect,” she says.


7:45: It’s a perfect spring morning in Manhattan’s Upper West Side, clear sky and 65 degrees. We ring the doorbell at WBF, and are greeted by rehabber Lily Lugo—and the pungent smell of pigeon poop. She’s stacking pigeon cages and getting organized for what could be a busy day. “We’ll see what happens,” she says. “It was high migration last night. I’m kind of nervous.”

A longtime animal caretaker who previously worked at the Queens and Central Park zoos, Lugo started volunteering at WBF in August 2020. She was hired full time in October 2021 and promoted to rehabber in March. (She also makes avian and NYC-themed jewelry.) Lugo’s primary responsibility is songbird care, so she’ll be our guide for the day as we await any collision patients that might come in. Other staff will spend most of the day administering food and medicines to 550 patients in the background as we focus on intaking new patients.


7:47: On our second loop of Brookfield, we find another yellowthroat, smack in the same corner spot—again. But this one is dead. “Still warm,” Breyer says as she picks up the male. We’d just been here. We only walked around the building once. And yet in that time, a bird had died. Died after surviving who knows what for who knows how many miles from its starting point, likely somewhere in Mexico or Central America. It all seems so unfair and so unnecessary. 

7:51: Breyer’s phone pings. It’s a text from Hilary Berliner, an off-duty volunteer who found a bird on her way to work. Another Common Yellowthroat. They must have had a big flight last night. Berliner is asking how to contact a PSF listserv, which volunteers use to coordinate shifts and ID birds, to see if someone can take the bird to WBF for her. 


7:53: On the walk to the second and final address on their route, Lincks and Winkler talk about how they started volunteering with PSF. Both have been involved with animal-focused causes for years, but Winkler, at least, is relatively new to birding. Like many, she started paying more attention to the birds around her during the pandemic. She had never really considered the risks birds face as they navigate the cityscape. Now, she sees those dangers as part of a larger story of declining species of all kinds, often due to human activity. Volunteering with PSF is a small, but concrete, action she can take to protect them.


8:00: We’re getting close to wrapping up, but Breyer wants to check out the bad corner at Brookfield “one last time—my famous last words.” Good thing we do: We find a dead female Northern Parula not too far from the spot where we found the redstart and two yellowthroats. This one clearly hit a nearby, decal-free skywalk in the 15 minutes we’ve been gone. “That’s why it’s so hard for me to leave,” Breyer says.

Our count stands at 15 birds. Four are alive and in Breyer’s bag awaiting transport—three Common Yellowthroats and an American Redstart. When storing and transporting live birds, “the most important thing is that they’re just in a dark and quiet place,” Breyer says. She can typically fit 15 brown paper bags with birds inside in a large shopping bag, but on busy days, when she runs out of space, she’ll clip small bags to the outside of the larger one. “Sometimes the birds are really active in there,” she tells me. “Sometimes I’ll have two bags. It’s like the hospice bag and the waiting room bag.”


8:04: Lincks and Winkler arrive at 590 Madison Avenue. Neither has yet found a dead or injured bird at this address, which NYC Audubon added to the route this spring. After looping around the building, they stop a moment to look into the tree-filled atrium, wondering aloud if the several House Sparrows flitting between tables are all right in there.

The dead Canada Warbler is the Columbus Circle route’s only bird: an easy day, and not too depressing. Lincks and Winkler linger to talk about the morning and their experience volunteering. “I think the word needs to get out to the general public, because they don’t know,” Winkler says about window collisions. “They get very upset when they find out.”


8:09: We begin our final sweep of the morning. The city is fully awake, buzzing with rush-hour energy. “This is when I start seeing my colleagues—I work in this building,” Breyer says as we pass Brookfield Place. It’s a twist I did not see coming. “A lot of times when they see me, I have a dead bird in my hand, hair sticking straight up.” We don’t see any coworkers this morning, but we do meet a cleaning guy Breyer is friendly with. “Morning! Find any birds today?” he asks cheerfully. So far, he’s had a quiet morning himself. “Hopefully it stays like that,” he says. “A good day.”


8:10: The first rescuer of the day brings in a European Starling fledgling, discovered on the ground under its nest. She was walking along 85th Street when a bystander pointed out the young bird sitting on the sidewalk. She took it home and held it in her hands to calm it down, before bringing it to Columbus Avenue for treatment. “I hope it’s gonna be okay,” she says. Lugo administers an anti-mite treatment and, to keep the fledgling warm, puts it in a brooder where, over the course of the day, it will be joined by 25 more starling fledglings. 

In spring they are among WBF’s most common patients due not to injury but to good intentions. Most fledglings on the ground should be left alone; their parents are nearby and feeding them. But that doesn’t stop people from “rescuing” what appears to be a helpless baby bird.


8:24: With no more birds found and foot traffic heavy, we call it a morning and catch an uptown 2 train toward WBF. “And now I’m just the crazy lady with birds on the train,” Breyer jokes as she puts the bag next to her on the seat. She promptly pulls out a stack of entry forms from her backpack and begins filling them out to expedite the drop-off process. “It can get pretty busy there,” she says. “A lot of times people will be in the vestibule filling out their information. I just walk in and drop them off.”


8:25: Finished for the day, Lincks and Winkler head home. They each make a habit of walking through Central Park on their way, appreciating the abundance of living birds—another reason Lincks brings along her binoculars. “We are stewards to hundreds of beautiful birds who pass through our city,” Lincks says. “We’re so lucky!”


8:39: While we wait for new patients, the staff go about their morning routines. Luis Ochoa puts together a meal for goslings: homemade pond muck—greens blended with bloodworms and thiamine—plus some lettuce and birdseed. Meanwhile Suzanne Highland feeds the starling fledglings, who mechanically purr pshh pshh while hopping around their temporary shelter in the front window of the clinic.


8:45: Berliner’s email has hit the listserv, and she’s still looking for someone to take the bird she found up to the clinic. We decide to pick it up. We make plans to meet her outside her workplace and head to Lexington Avenue to catch a downtown train.


8:49: Heading uptown on the train, Breyer says that, along with logging data on her volunteer shifts for PSF, she reports birds she finds while off-duty to dBird, a platform NYC Audubon created for tracking bird mortality. She also logs her data on the app iNaturalist, and keeps a Google Sheet with info on every bird she has found. She guesses the total sits around 1,300 birds. Among the most unexpected species she’s found in the city: Virginia Rail, Sora, and a Chuck-will’s-widow—a secretive and odd-looking nightjar that she found on an awning. “That was really astonishing,” she says of the Chuck.

9:02: We emerge from underground on the Upper West Side. It’s shaping up to be a gorgeous spring day. At sidewalk cafes people sip coffees and eat pastries as we walk past with our bag full of live birds. 

At WBF, two people are outside filling out intake forms. Lugo greets Breyer with a warm welcome. Kneeling in the doorway, Breyer hands over the paperwork and each bag for processing. With some luck, these birds will recover quickly and be released to continue their journeys.


9:23: The birds Breyer dropped off are resting quietly in the brown paper bags they arrived in. When they start moving again—“rattling around in there,” says Rita McMahon, WBF founder and director—it means they’re ready for an examination. 


9:26: We meet Berliner on a street corner not far from Union Square. She typically patrols the West Street route on Saturdays, but this morning she found a stunned Common Yellowthroat while walking to the school where she works as a math specialist. It’s not the first time she’s come across birds at that particular building: “I always loop around it, because I’ve found a lot there.”

Luckily, Berliner was prepared: She had a paper bag and was able to scoop up the warbler and take him with her to school. “I just had it quietly on my desk, and I had a kindergartener in there I was working with, and I was like, please don’t make any noise.” The yellowthroat is mostly quiet in his bag but rustles around as Berliner hands him off. We say goodbye and head back to the train to make the trip uptown.


9:27: A Mourning Dove is dropped off, found on the ground at 425 Amsterdam Avenue. It’s bleeding. The diagnosis: cat attack. The bite went through the wing; McMahon suspects it’s a compound fracture. A cat bite also transmits an infection-causing bacterium, which is treated with Clavamox. If the vets can get Clavamox into a cat victim within 24 hours, it’ll typically recover, so long as it can heal from its injuries. Longer than that and it will be a harder fight.

McMahon carries the dove downstairs to a treatment room off the main pigeon facility and prepares to administer oxygen with isofluorane gas, a general anesthetic. Once the bird is unconscious, McMahon can do a thorough examination without causing additional pain. That exam will help her decide whether the dove needs to be euthanized. “It’s very subdued for a Mourning Dove, which indicates internal injuries,” she says. She cradles the bird on a towel, places a gas mask on its face, and waits for its eyes to close.

Once the bird is under, McMahon flips it onto its back and extends its wing. The underside is bleeding from a wound, and feathers are torn with broken shafts. “Shh, shh, shh,” McMahon soothes the sleeping dove. The bird is limp and breathing gently. The medical report: Wrist, radius, and ulna are broken. It’s a compound fracture. “He has to go,” she says.


9:35: Considering last night’s huge flight, I head to Central Park to check out the birding scene. The paths and roads are swarming with runners and walkers. The trees buzz with birdsong.

At The Loch, a densely wooded area with a stream, birders and photographers huddle in groups and scurry from one area to the next, sharing intel as they pass. Apparently a Hooded Warbler is singing up the path, and a Canada Warbler was recently spotted along the stream. Black-throated Blue Warbler, Chestnut-sided Warbler, Rose-breasted Grosbeak, Northern Waterthrush—the list grows by the minute.

Sitting on a bench, an English birder who traveled to New York just for spring migration looks overwhelmed as he tries to record all the birds he’s seen. “This is the best birding in my life,” he says, shaking his head in disbelief.


9:48: McMahon pulls .3 mL of pink Pentobarbitol into a syringe. She grasps the dove in her left hand and injects the medicine into its chest cavity. For a few minutes it sits there on the towel, flickering its eyelids and occasionally opening and closing its beak. “He’s dreaming,” McMahon tells me. 

We stay with the bird through its death. “He feels no pain,” she says. She holds a stethoscope to his chest to see if he’s still with us. He is. But only for a few more moments. 

9:55: Amanda Parsels, a PSF volunteer, arrives after her route through the Financial District, which covers South Street Seaport to the Staten Island Ferry launch. She often finds birds that collided with buildings along FDR Drive. “There are lots of collisions coming over the water,” she says. She drops off an Ovenbird and a Black-throated Green Warbler; the bags are placed with the other warblers in the intake room to quiet down.

10:02: One of the bags Breyer dropped off starts rattling. That means it’s time for Lugo to check on the collision victims. The first patient: an American Redstart, recovered from the east facade of 200 Liberty Place, part of the Brookfield Place complex. Lugo pulls the chirping songbird out of the paper bag, its head peeking out between her two fingers. “It’s pretty reactive, so this is great,” she says. She releases the alert bird inside a basket on top of a digital scale. It weighs eight grams: “Still tiny,” Lugo says. She checks if its wings are uneven, then places it on the table so she can wrap a piece of marked tape around its ankle—a hospital bracelet for a warbler.

Lugo picks the bird back up to show it to us. Seconds later, the redstart escapes her hands and zips around the room, flying to the ceiling before hiding behind an emergency battery for the brooder. “This is bound to happen,” she says. Lugo quickly recovers the redstart and puts it in a soft carrier bag.


10:15: After a packed train and a transfer, we make it to WBF. Berliner had already printed and filled out an intake form, so our handoff with the staff there is quick and easy.


10:21: Another bag is rattling, and Lugo pulls out a female Common Yellowthroat. She is checking if the bird, recovered from the west facade of 4WTC, has any visible injuries when it breaks free from her hands and starts flying frantically around the room. As Lugo looks for a small net, the yellowthroat squeezes itself through the cracked-open door (our bad!) and escapes into the lobby. Lugo says this happens often (“First time happening to me, though”), but it’s inconvenient for the staff and unsafe for the birds. “We don’t like it when it happens,” McMahon says. The search for the loose warbler is on.

10:33: As the female yellowthroat lurks somewhere in the lobby, we turn to other patients. Just like the previous two birds, a 10-gram male Common Yellowthroat jumps out of Lugo’s hand. But this time, she is ready with a net. “They are escape artists,” she says. 

Taking flight may seem like a sign of good health for a collision victim. But it’s not necessarily the case, Lugo says: Birds can have internal damage or a concussion after hitting a window. WBF keeps all collision victims for at least three days to monitor their health before releasing them back to the wild.

10:37: Now it’s another male Common Yellowthroat’s turn for patient intake; Breyer recovered him from the east facade of 200 Liberty Street. He chirps loudly when Lugo takes him out of the paper bag. “Angry little dude,” Lugo says. This time, she grasps him quite strongly to prevent escape. After weighing, he joins the redstart and yellowthroat in a soft carrier bag.

10:42: We have one last Common Yellowthroat to process, but this one is in a different mood than the rest. The 12-gram male sits quietly on a towel inside the scale basket when Lugo weighs him—no fluttering about and no escape attempts. We breathe a sigh of relief when he hops around a little and chirps.

As we wind down the intake operation, we hear a triumphant yell from the lobby. Nearly 30 minutes after it escaped the intake room, McMahon has finally recovered the female Common Yellowthroat. The bird hid behind a turtle aquarium for some time, and later near a washing machine. McMahon holds her tightly and brings her to the intake room for weighing and tagging. 

10:59: Ochoa and Lugo don surgical dress and enter a back room to feed the largest collision victim currently in WBF’s care: a Red-tailed Hawk. The raptor, admitted to WBF on May 12, is suffering from head trauma from colliding with a car or building window—its retina is displaced from the impact. Ochoa checks on its eyes using a flashlight before he and Lugo feed it liquified food, water, and medicine. “His eye—I’ve never seen anything so bad on a hawk before,” Lugo says. “That was a pretty bad collision.”

Raptors usually spend a week at most at WBF for stabilization treatment. “They never spend, like, a month here,” Ochoa says. “Unfortunately they almost always either die before that, or we transport them to a raptor sanctuary in New Jersey.” The Raptor Trust, located about 20 miles west of Newark, hosts an advanced raptor medical facility (including intensive care) and large outdoor aviary cages where birds too injured for release can live out the rest of their days.

McMahon remarks that today is a slow day. By its end, 74 new patients will have arrived. In contrast, WBF last week had its second-busiest day ever, with 110 birds brought in on May 13. Overall, this year’s patient count is high. McMahon hasn’t done a full analysis, but she’s so far seen a 38 percent increase for this time of year. What’s driving it? It could be early migration inflating this year’s count, more collisions, more migrators—or that more people know to bring injured birds to WBF for care.


11:08: After dropping off the yellowthroat at WBF, we head to NYC Audubon’s 15th floor office on West 23rd Street, where Katherine Chen is looking over the latest data submitted by PSF volunteers. Chen oversees the project, along with the organization’s other community science work, like horseshoe crab monitoring, which overlaps with spring migration. She will eventually do a thorough check of all the data, and all bird IDs, but right now she’s looking for obvious mistakes. She spots one: A volunteer marked their patrol time as “PM” not “AM.” Chen corrects the time and keeps scrolling. With 122 volunteers monitoring 13 routes, there are lots of data.

Having reviewed all the entries submitted so far today, Chen takes a break from the massive spreadsheet. Before she joined NYC Audubon, Chen was already researching building collisions as an ecology master’s student. She volunteered as a monitor in fall 2021, patrolling the Central Park North route. She sees direct value in the project: “It helps us understand collisions and what’s causing them,” she says, “And also the effects of retrofits.” 

Chen keeps tabs on retrofits, when buildings around the city install window treatments and other collision-deterrents, sometimes in consultation with NYC Audubon. When the building in question is part of a PSF route, she says, monitoring often shows the retrofits were highly effective at reducing collisions and bird deaths. (PSF data showed that the Jacob K. Javits Convention Center in Manhattan, for example, was once among the city’s top bird killers. But changes recommended by NYC Audubon and implemented in 2013 led to a more than 90 percent decrease in collisions at the site.) And if volunteers are still finding dead and injured birds, they can follow up with building management and suggest fixes. “It’s always great to see buildings get retrofitted and make the city safer,” Chen says, “But we also want to see legislation that affects more than just individual buildings.”

NYC Audubon has already helped secure some policy wins: A 2019 law requires all construction projects begun since January 2021 to use bird-friendly materials on exteriors up to 75 feet off the ground, where birds are most likely to strike, among other requirements. In December of that year, the city council also passed “Lights Out” legislation requiring all city-owned buildings to turn off nonessential outdoor lighting between 11 pm and 6 am during fall and spring migration. It was a major victory, Chen says, but one that applies only to a small percentage of the city’s buildings. The organization is supporting new legislation to extend the rule to privately owned buildings.

Chen says this work has permanently changed her perspective on the city’s iconic skyline. “I’ll be walking with my friends, and they say, ‘Oh, that’s a cool building!’ And I’m just thinking, that’s a lot of glass.”


11:12: Lugo returns to the intake room to process the patients Parsels brought in a little over an hour ago. An Ovenbird, weighing 19 grams and found at 80 Maiden Lane, is subdued on the scale. “Quiet,” she remarks. Then a striking Black-throated Green Warbler, found by 55 Water Street, fights to escape Lugo’s grip: “He’s angry.” He weighs nine grams. They join the redstart and yellowthroats in the soft carrier.

11:23: Lugo picks up the warbler-filled carrier and totes it down the stairs to the songbird rehabilitation room, known as the flyway, where birds rest in cloth carriers. She transfers the quiet Ovenbird into a carrier with five other quiet Ovenbirds. Lugo calls them “quiet guys”—songbirds that are less feisty, perhaps indicating they need more rest and recovery (or are on the downswing). She always puts the quiet guys together, ideally grouped by species.

She swats overhead: “Sorry about the black soldier flies.” WBF staff keep fly grubs here to feed the birds, and any that hatch into adult flies are used for enrichment to keep the songbirds active and in good hunting practice. 

There are at least a dozen stacked soft carriers holding different kinds of birds. One houses several Scarlet Tanagers; another contains thrushes and, in another, vireos. Thrushes and vireos will fight other songbirds, so they must be separated. “Vireos are feisty,” Lugo says. 

Beyond “quiet guys,” there are two other main rehab categories: “BAR guys,” for bright, alert, and reactive,” and “ADR guys,” which means they “ain’t doing right,” Lugo says. BAR guys are pretty much ready for release, as long as they’re flying well and their eyes are healthy. ADR guys are not doing well, and the rehabbers aren’t sure what is wrong with them. 

Our new arrivals—the Common Yellowthroats, American Redstart, Ovenbird, and Black-throated Green—will stay here for a few days to recover, dining on black soldier fly grubs, mealworms, waxworms, and crickets. Like all other collision patients, they’ll be dosed with an anti-inflammatory medication called medicam. If they’re classified as BAR guys in a couple days, they’ll be released in nearby Central Park. Others will spend more time in rehab. However, the longer they stay here, the more likely it is that their collision injuries are fatal. Most are: Only 39 percent of collision victims are ultimately released, McMahon says, although warblers overall have a higher survivorship than particularly susceptible species like American Woodcock, which struggle to recover after striking a building.

1:35: After lunch, it’s time to release the BAR guys that have already spent several days at WBF regaining their strength. Lugo loads three soft carriers, each containing songbirds, into shopping bags and we set off for Tanner’s Spring, a popular birding spot in Central Park.

1:51: There is a small group of birders gathered when we reach the natural spring protected by boughs of overhead foliage. Lugo sets the soft carriers on a stone bench next to a seated birder. We stand back and wait. First she releases a group of six songbirds: Common Yellowthroats, mainly. They fly out, one by one, zoom ahead and then loop up and away. One lands in a tree nearby; we peer at it through binoculars. Then a Red-bellied Woodpecker struggles to find the exit of its carrier before flying off to a distant tree. Lastly a Worm-eating Warbler hops around with the carrier door open for a full minute before it, too, flies free and lands on a tree nearby. The mood is light and optimistic as we consider the trials the birds have survived and the long journeys they have before them. 

Behind us, a Blue Jay pesters a small songbird right near the spot where the Worm-eating Warbler had alighted. Then Audubon social media manager Luz Muñoz Huber, who joined us with her partner and dog for the release, hustles up beside us. “My partner just saw a Blue Jay carrying off the Worm-eating Warbler,” she whispers. We stand horrified. It’s disturbing that the songbird flew all this way from Central America or the Caribbean, survived a collision with a Manhattan building, spent days in recovery at WBF—only to become prey when it had just rejoined the wild. 

It’s sad and brutal. But that is also the nature of rescue work. These birds make dangerous journeys every spring and fall. They face predators and bad weather, as well as human impacts like building collisions, car traffic, pollution, cat attacks, habitat destruction, and more. The workers at WBF spend their days giving every injured bird a chance to continue their migrations. But even when Lugo and the committed rehabbers are able to save a bird, they can’t protect it forever. They can only send it back out into the world to make its own way. 

Reporting by Andrew Del-Colle (World Trade Center Complex), Zoe Grueskin (Columbus Circle), and Kharishar Kahfi and Hannah Waters (Wild Bird Fund). Editor’s note: Grueskin, Audubon’s editorial fellow, is a Project Safe Flight volunteer.