Hoping to protect migrating birds and reduce light pollution overall, Doylestown Borough recently adopted an ordinance intended to do both.
Lights Out Doylestown is the community’s first effort asking residents and businesses to turn off or dim exterior and interior lighting at night, as officials embrace a growing movement to ease navigation challenges for migrating birds in highly lit areas. The voluntary measure requests “lights out” between 11 p.m. and 5 a.m. until Nov. 15.
A recent study by the American Ornithological Society estimated between 100 million and one billion birds are killed in the U.S. every year due to collisions with buildings. Most songbirds migrate at night and light pollution is disruptive and harmful, according to the AOS. Birds are attracted to bright lights on large buildings, which can be fatal, in the same way moths are drawn to porch lights, the AOS said.
Bird migration across the United States takes place largely between Aug. 15 and Nov. 15.
Even the exterior lights of the Gateway Arch in St. Louis will go dark throughout September, said the National Park Service. About 40% of the country’s migratory waterfowl use the Mississippi River corridor for their flight path, according to the park service.
The five-story, 285,000-square-foot Bucks County Justice Center sits in the center of the borough at 100 N. Main St. Since its completion in 2015, both interior and exterior lighting has remained on throughout the night.
Asked if the building would be reducing its lighting, Karyn Hyland, the borough’s director of building and zoning, said, “We acknowledge the justice center is a concern.” The borough, she said, is working with the county’s director of operations to see if anything might be done to limit the center’s lighting.
“The staff has been very cooperative,” emphasized the director, however, limiting the lighting in the large facility is complex.
Additionally, the ordinance requires new construction to meet updated standards to reduce light spillover, glare and other light reduction measures. Existing buildings are not affected by the ordinance.
For example, lighting for parking lots, storage areas and building entrances will need to be aimed downward. Lighted signs, building facades and other lit surfaces will need shields that restrict how far the light travels to neighboring properties, roads and the sky.
Seasonal lighting, such as Christmas lights, and emergency lighting are exempt from the new regulations, which require “energy-efficient” lights be used. In general, outdoor lights need to be off between 10 p.m. and dawn, according to the new law.
While LED lighting has many benefits, Hyland said, there’s “growing concern,” about its use. It draws less power and saves money but “it’s also more intense in several ways, with its more focused stark white, almost blue light,” she noted.
“That doesn’t mean they’re bad, but they require more attention,” said the director.
More than 80% of the world’s population lives under “light-polluted” skies, according to a study by the scientific journal, Science Advances.