By Frank Kummer

The Philadelphia Inquirer

PHILADELPHIA — Stephen Maciejewski dropped to a knee on a Philadelphia sidewalk Wednesday morning and gently scooped up a yellow-billed cuckoo that had smashed into a skyscraper and died on its way to Central America or the West Indies.

“This probably happened yesterday,” said Maciejewski, a 71-year-old retired social worker and volunteer for Audubon Pennsylvania. He labeled a plastic bag with the time, date and location, tucked the slim migrator into it, and continued his rounds.

Maciejewski gets emotional when he speaks about all the birds he finds, but nothing, he says, prepared him for what happened on Friday.

“So many birds were falling out of the sky we didn’t know what was going on,” he said, choking up. “It was a really catastrophic event. The last time something like this happened was in 1948.”

On Friday, an estimated 1,000 to 1,500 birds flew into buildings in Center City overnight and into early morning during what he Maciejewski called a “perfect storm” of avian calamity.

He collected 400 birds during between 5 and 8 a.m. in the three-square-block radius he regularly covers —an astonishing number, according to a Pennsylvania Audubon official.

“There were so many, I was picking up five at a time,” Maciejewski said. “One guy from building maintenance dumped 75 living and dead birds in front of me as if it were a collection.”

Maciejewski logs each bird, noting its flight path, time and location of impact.

“There were so many birds I ran out of supplies.”

He can collect only so many birds because building maintenance crews and Center City District workers sweep detritus, including bird bodies, early each morning before commuters arrive. Maciejewski has established a rapport with some workers who save birds for him.

“We collected almost 100 birds on one small roof,” he said of Friday’s haul.

In the five days since, things returned to normal, and Maciejewski collected no more than 20 birds a morning.

Why so many birds in one day? Maciejewski and Pennsylvania Audubon can only guess.

“This is complicated stuff,” Maciejewski said.

It appears weather events lined up for the worse during what was likely the peak of migratory birds’ flight from Canada, Maine, upstate New York and elsewhere toward Central and South America. A sudden plunge in temperatures could have prompted the birds to start their flights en masse.

In Philadelphia, Friday brought low cloud cover, light rain, and a full moon, all of which could have had an influence. Those conditions could have pushed the birds lower. Birds flying from remote Northern habitats might have little experience with glass.

As they reached Philly in the dark, the birds would have been attracted to the lights inside the buildings. Some of the skyscrapers have indoor lobbies and atriums, which could have led birds to think they could land there.

On any given morning, street trees reflect in the glass, making it appear they are inside buildings.

He says he routinely finds the most downed birds near the two Comcast buildings, BNY Mellon Center, and Logan Square, but also just about anywhere. On Wednesday, the warbler was killed at 15th and Market.

Inquirer columnist Inga Saffron has written about the impact of glass buildings on birds in the past. The U.S. House of Representatives in July introduced the Bird-Safe Buildings Act of 2019. If approved, it would require buildings to use methods designed to eliminate bird collisions.

“We have to bring people together to make the glass friendlier to birds,” Maciejewski said. “We’re contributing to the extinction of American songbirds.”

Keith Russell, an ornithologist with Pennsylvania Audubon, said he placed the birds Maciejewski collected Friday in a freezer in his Germantown home. The birds will be taken to the Academy of Natural Sciences of Drexel and logged.

Russell said he knows that Friday was a rare event because a network of people, including employees at the Academy, keep their eyes peeled during regular rounds.

He still hasn’t been able to sort through all the species collected Oct. 2, but they included various warblers, cuckoo’s and others. The birds are counted each morning for a Pennsylvania Audubon database.

“This is a very big issue in the world of bird conservation,” Russell said. “The estimates are 350,000 to a million birds die every year colliding with buildings.”

Russell has been with Pennsylvania Audubon since 2003. But before that he worked at the Academy’s bird department.

He said the last big bird of this scope happened 72 years ago when a massive flock struck what was then the PSFS building at 12th and Market, now a Lowe’s hotel.

“Think of what the birds experience,” Russell said. “It’s like being on a dark highway and you suddenly see headlights. You don’t see anything else but those lights. On Oct. 2, birds could have been overtaken by a rainstorm, or conditions. They think ‘We’ve got to stop, and they see all those buildings and bright lights. …’

“For birds, it was the equivalent of a couple of jumbo jets going down and everyone dies.”