Philadelphia To Dim Lights To Make It Safer For Birds In Flight

The lights of Philadelphia might not shine as bright in the coming weeks in an effort to prevent millions of migrating birds that pass through twice a year from slamming into skyscrapers and crashing to the sidewalk. Bird Safe Philly has announced the Lights Out Philly initiative, a voluntary program in which as many external and internal lights in buildings are turned off or dimmed at night during the spring and fall. Birds navigate during migration using celestial cues and when they can't see stars on a cloudy night they get confused by bright city lights. Windows pose a problem because birds might see a reflection of trees or the sky. Scientists estimate between 365 million and one billion birds are killed by collisions with buildings or other outdoor structures in the U.S. every year and those crashes are taking a toll on some species.