Philadelphia Skyscrapers Turn Lights Off to Save Migrating Birds

A new program aimed at reducing deadly collisions with buildings for migrating birds is set to begin on April 1

Philadelphia skyline at night
The lights of the Philadelphia skyline at night. Morgan Burke via Flickr under CC BY-NC-ND 2.0

Every spring and fall, millions of migrating birds pass through Philadelphia, with the majority of these flights taking place at night. But as these avian odysseys weave through the city’s twinkling lights, the skyline’s sparkle can cause a significant number of birds to become disoriented, leading them to smash into windows or the sides of buildings and, ultimately, litter the sidewalks with their feathered corpses.

The issue came to a head on a cloudy night last October. An estimated 1,000 to 1,500 birds died in a roughly three-block radius located in downtown Philadelphia on a single Friday night, Frank Kummer of the Philadelphia Inquirer reported at the time.

Now, spurred in part by the Inquirer’s coverage, some of the city’s most prominent skyscrapers are going to be turning their lights off after dark as part of a voluntary initiative called Lights Out Philly aimed at helping migrating birds pass through the city safely, Kummer reports for the Inquirer.

The mass-collision event last October may have been the largest in 70 years, reports Shawn Marsh for the Associated Press (AP), but the issue of city lights causing bird deaths is anything but new.

“We have specimens in the academy’s ornithology collection from a kill that happened when lights were first installed on Philadelphia’s City Hall tower in 1896,” Jason Weckstein, associate curator of ornithology at Drexel University’s Academy of Natural Sciences, tells the AP.

Per the AP, birds become disoriented by artificial light because at night they use the stars and moon to navigate. On cloudy nights, the glow of urban centers becomes even more confusing because birds can’t see the sky. Mirror-like windows can also cause problems by presenting a false picture of the bird’s path ahead, perhaps reflecting sky or trees where there is only a pane of glass. Researchers estimate that between 365 million and one billion birds are killed by collisions with buildings each year, according to the AP.

The buildings participating in Lights Out Philly include the Comcast towers, BNY Mellon Center, the Liberty Place building and 12 other building operators or owners, according to the Inquirer. The program has also been endorsed by Philadelphia’s Office of Sustainability, the Building Owners and Managers Association Philadelphia and the Building Industry Association of Philadelphia.

Lights Out Philly officially starts on April 1 and lasts until May 31, with the fall season running from August 15 through November 15. All buildings participating are asked to kill the lights between midnight and 6 a.m., especially lights that shine in the buildings’ upper levels, lobbies and atriums, per the AP.

Philadelphia joins more than 30 other cities, such as New York, Boston, Atlanta and Washington D.C., that already have Lights Out programs of their own, according to a statement from the National Audubon Society which established the first such program in 1999 in Chicago.

Per the AP, the coalition behind Lights Out Philly, which includes Audubon Mid-Atlantic and two local Audubon chapters, the Drexel University Academy of Natural Sciences, and the Delaware Valley Ornithological Club, plans to increase their monitoring efforts during migration seasons to identify problem areas and assess the program’s success.

“We are heartened by all the efforts in our community to join together in this critical initiative to save so many birds from unnecessary harm and even death,” Scott Cooper, president and CEO of the Academy of Natural Sciences, tells the Inquirer. “A simple thing like turning out lights can help thousands of birds safely navigate our challenging urban environment.”

Also speaking with the Inquirer, Christine Knapp, director of Philadelphia’s Office of Sustainability, says Lights Out Philly will not only save “countless birds,” but also save energy and reduce the city’s carbon emissions.

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