As the sun rises on a workday in downtown Birmingham, the human population in the city’s center typically includes a small group: first responders, cooks, cleaners, security guards, the homeless and those seeking to get some quiet time in the office before their colleagues arrive.

During the past two years, that early morning population also frequently has included a woman walking slowly and looking closely at the sidewalks, plazas and lawns outside glass-fronted buildings. Sometimes — as much as 20 times on the morning of Oct. 13 — she would pause, kneel, remove a small brown paper sack from her shoulder bag and carefully place inside it the carcass of a dead bird, usually one that had been migrating through town.

Her name is Jessie Griswold. She is the lead animal care professional at the Birmingham Zoo’s Animal Health Center. She also is an unabashed “bird nerd.” She recently concluded work on a research grant — the only type of its kind recently done in the state — to bring to local light a problem that has afflicted Birmingham and other metropolitan areas around the country.

The problem? Bird deaths from window collisions.

“Birmingham doesn’t have as heavy an impact on migratory (bird) populations as other, larger cities,” Griswold said in a recent interview. “But from what I’ve seen downtown, it is a problem, and from what I hear from people saying, ‘We have birds hitting our windows all the time at home, it is a major problem.”

But, she added, “Most people don’t know of the problem. That’s another part of my project. I want to show that it is a problem and offer solutions, whether you’re a homeowner or whether you own the building downtown.”

Bird collision deaths have been a problem for some time. Along with loss of habitat, pesticide use, declining insect populations and other factors, it is one of the reasons North America has three billion fewer birds than it did in 1970. That grim number was in a study published last fall in Science Magazine. In 2014, another article in Science cited a report that stated that between 365 million to nearly a billion birds die each year from “crashing into windows in the United States.”

Griswold notes that only one other “human-induced cause” — outdoor cats — kills more birds.

“That’s a whole ‘nother issue in itself,” she said. “I have two cats, and they are strictly inside.”

During her research, Griswold did her work five days a week, rising before dawn to drive downtown and walk through the heart of the city center. After that, she would drive close to the massive glass enclosure of Children’s Hospital, circle the facility on foot, then proceed to UAB and continue her walk around a big part of the campus, including the Campus Green, an open corridor with trees and walkways and flanked by such glass-fronted structures as the Campus Recreation Center, structures with interiors that remain lighted at night.

“It definitely takes a different person to walk around at the crack of dawn … and look for dead things, but that kind of thing doesn’t bother me that much,” Griswold said. “I’m OK with it. It’s a problem that we want to solve.”

“The more people who know about it, the more windows that can be fixed,” she said. “And that’s the whole point of the project … to educate the public.”

Because she was working alone and not doing her research 24/7, and because she was not covering every square inch of downtown or UAB pavement, Griswold knows she missed plenty of bird carcasses and thus missed some findings that might lead her to draw more definitive conclusions about what types of birds are dying and where. But she did not come up empty-handed.

During her two years of walking her two-mile route, Griswold collected 438 birds outside buildings. Most of them were dead, more than a few flattened by footsteps where they lay. Eighty-six were alive, apparently stunned or injured by a window collision, and she took them to the zoo, where they were triaged and then taken for more treatment at the Alabama Wildlife Center at Oak Mountain State Park.

Ovenbirds, Hummingbirds and Others Die

Heading Griswold’s collection list was the ovenbird, a species that, according to the Cornell Lab of Ornithology, migrates through most of Alabama but breeds in the Tennessee Valley and builds a nest that resembles a Dutch oven.

All in all, Griswold found 65 ovenbirds, 52 of which were dead. Twelve others were alive, and they eventually ended up at the Wildlife Center. Another that she found alive subsequently died.

Other species in Griswold’s top 10 most collected list include the common yellowthroat (35 total, 22 dead), the Tennessee warbler (24 total, 22 dead), the ruby-throated hummingbird (21, all dead), the indigo bunting (14, all dead) and, to her surprise, the yellow-billed cuckoo (10, nine dead), a bird she’d been accustomed to seeing in fields.

Obviously, finding birds outside glass buildings was good for the results Griswold hopes to ultimately accomplish, but good collection days were not good for her bird-loving soul, particularly when the tally included species like the black-and-white warbler.

“That’s my favorite warbler,” Griswold said. “Seeing a dead one is not fun for me.”

All in all, according to a listing from the Alabama Ornithological Society published by the Alabama Department of Conservation and Natural Resources, more than 400 species of birds spend all or part of the calendar year here. About 80 generally migrate through here in the spring and fall, and those migratory birds are the most vulnerable to window collisions, and, as Griswold has noted, not just during daytime hours.

A Trick on the Eyes

Here is an overall description of the problem from The Atlanta Audubon Society, one of a number of organizations and entities that Griswold has monitored to gain ideas for her project:

“Bright lights at night can disorientate migrating birds, causing them to crash into structures or ‘trap’ them in beams of light leading to exhaustion. Birds also struggle with reflective surfaces during the day as they stop and feed or rest. Shiny glass exteriors, internal plants near windows, glass corners, and lots of greenery close to buildings all can be deadly as birds struggle determining what is and isn’t a reflection and where there are open flyways.” According to the CityLab website, birds “haven’t evolved to recognize glass as a barrier — skyscrapers have only cropped up over the last century — which means that when birds see the sky or a tree reflected in glass, they will continue flying towards it.”

In the fall of 2015, Atlanta Audubon started Project Safe Flight Atlanta, a project similar to Griswold’s but involving multiple volunteers and encompassing a larger area than what she has covered alone in her parcel of Birmingham. So far, Atlanta volunteers have collected more than 1,400 birds representing 105 species, and ruby-throated hummingbirds are what they have collected the most.

Meanwhile, according to news reports, the New York City Council has just approved a measure to require developers “to use bird-friendly glass in new properties.” Among other things, the law would “affect new development by requiring that 90 percent of wall surfaces below 75 feet are bird-safe.”

Fixes Include Dots to Decals

What are examples of making surfaces bird-safe? At the zoo, Griswold has placed rows of dots on the glass enclosing part of the Barbara Ingalls Shook Black Bear Trail and on part of the glass barrier around the coyote habitat. The problem is that, over time, the dots have been disappearing.

“We’re going to have to find a different solution,” Griswold said.

There are plenty of them out there, ranging from safety film, special tape, reflectors and decals to vertical blinds or cords, to sprays and stencils that give windows a pattern virtually invisible to humans but visible to birds.

By using those or other measures on collision-prone windows in their own dwellings, homeowners would save plenty of birds. But Griswold said that greater numbers of birds would benefit if those designing large glass-fronted buildings or those owning such structures took bird-friendly steps. As awareness of the collision problem grows, Griswold hopes to see that happen, but it may take a city ordinance to have even more of an effect.

“I would like to see that,” Griswold said. “It will take a lot of effort and a lot of groups coming together, and I think we’re still in the early stages of that here. I have big ideas and big plans, but I’m one small person.”

Meanwhile, this “small person” plans to spread the bird collision word by sharing her research findings with Alabama Audubon.

For more information on bird-window collisions and possible solutions, you can contact Griswold at jgriswold@birminghamzoo.com.