Photo: The glass windows of the Martha Washington Library reflect trees and vegetation, Glenda Booth.
By Glenda C. Booth
Originally published in the Connection Newspapers, Oct. 24, 2024
On the Saturday overnight of Oct. 19-20, 352,400 birds crossed Fairfax County, most migrating to their wintering grounds. Every fall, around four billion birds fly from Canada into the United States and another 4.7 billion fly over the U.S. southern border, according to Cornell University experts. But birds face multiple hazards, including collisions into windows and human-caused light pollution, three speakers told 75 attendees at an Oct. 9 online program sponsored by the Northern Virginia Bird Alliance.
NVBA has launched a campaign to prevent bird deaths, citing a National Audubon Society study that found a 30 percent drop in bird populations in North America since 1970, which means more than one in four birds or three billion birds have been lost since then.
Most birds migrate in the fall to find food, explained Greg Butcher, retired Migratory Species Coordinator for U.S. Forest Service. While some birds like swallows and finches migrate during the day to feed on the wing, 80 percent migrate at night, he said.
Collisions with Glass
Over one billion birds die by colliding with glass in buildings in the U.S., Christine Sheppard of the American Bird Conservancy, told the group. A few bounce off, but “scavengers are good at snatching up carcasses,” she added.
“We are getting collisions everywhere because the birds are sucked into the built environment, not just high up in skyscrapers,” Sheppard explained. A Smithsonian Institution analysis estimated that houses and other buildings one-to-three stories tall account for 253 million bird fatalities; low-rise buildings four-to-11 stories high account for 339 million bird deaths; and high-rise buildings 11 floors and higher cause the deaths of 508,000 birds a year. Taller structures like skyscrapers have higher per building mortality rates, but residences are responsible for most because of their numbers.
Birds crash into windows because they perceive glass reflections of vegetation, landscapes or sky to be real and they try to reach the area. Last October, in one night, nearly 1,000 birds collided into Chicago’s mostly-glass McCormick Place Lakeside Center, the highest number on record then. American Bird Conservancy reports that once New York City’s Javits Convention Center was renovated and bird-friendly glass installed, collisions dropped by 90 percent.
NVBA is promoting bird-friendly designs for buildings and bird-friendly glass, for homes, for example, screens, decals and tape on windows’ exteriors.
Paracord hung in front of a window to warn birds not to fly into it. Photo: Powell Hutton
Some localities have adopted bird-friendly building requirements, Sheppard said, including Washington, D.C.; Howard County, Maryland; New York City; and Portland, Oregon.
Light Pollution
Laura Greenleaf from Dark Sky Virginia began by saying, “In the last 100 years, we’ve turned night into day … natural darkness is fundamental for all of us.” She contends that on the east coast, light pollution is increasing ten percent every year. The NVBA campaign brochure defines light pollution as “lights that are too bright, too white, mis-aligned or on all night,” like lit parking lots.
“We’re lighting up so much more than we need to, especially landscaping lighting,” she argued. “You can light sport fields without lighting the sky.”
Artificial night light affects birds’ foraging, predator-prey balances, emergence from shelter, communication, navigation and migration, Greenleaf maintained. “Insects are the foundation of the food web, but lights suck them out of the environment.”
Lights Out D.C. volunteers walk Washington’s streets before sunrise during the migration season and collect dead and stunned birds.
Advocates are urging government officials to enact policies to “adopt lighting, construction and other measures to protect birds and other wildlife from the worst impacts of our built-up environment,” explained Tom Blackburn, NVBA Advocacy Chair. He added, “Revisions to lighting ordinances could be very effective in reducing light pollution. Rapidly-developing areas such as Tysons, Reston and Leesburg could require new construction to include bird-safe windows and incorporate Dark Sky International’s Principles for Responsible Outdoor Lighting into building design.”
The campaign also seeks to “convince business owners to adopt ‘Lights Out for Birds’ practices during spring and fall migration seasons, as many other towns and cities have done and to convince developers and architects to incorporate bird-safe windows into building designs.”
Fairfax County
Government policies vary widely. Kelly M. Atkinson, with Fairfax County’s Planning and Development Department, said, “Fairfax County is committed to safeguarding local wildlife and has implemented measures to mitigate the effects of outdoor lighting on birds and other wildlife. In 2020, the county amended its Zoning Ordinance to adhere to updated lighting industry standards that prioritize energy efficiency and restrict outdoor lighting to a maximum color temperature of 3,000 K.
“During the review of commercial and multi-family proposals going through the public hearing process, we ask applicants to provide information on bird-friendly design strategies which could include window glazing, lighting practices to reduce light emitted during evening hours and incorporation of natural landscaping around the building. Additionally, the Fairfax County Park Authority actively advocates for dark sky-friendly initiatives, urging residents and businesses to adopt measures that reduce light pollution and protect local ecosystems.”
Blackburn responded, “I am very pleased that Fairfax County has taken steps to reduce the adverse impacts of our built-up environment on birds and other wildlife. I am hopeful that we can work with county officials to promote additional measures, including supporting a ‘Lights Out’ policy during migration and reducing the recommended color temperature for lighting to 2,500 K.”
Find out more:
Reducing collisions: https://abcbirds.org/glass-collisions/; www.Birdsmartglass.org.
Lights out: http://www.darkvirginiasky.org/
Bird migration: https://birdcast.info/
View the Oct. 9 NVBA webinar