Watch Clip
![](http://image.pbs.org/video-assets/6DwV0HG-asset-mezzanine-16x9-itEhNTA.jpg?resize=410x)
How Philadelphians are protecting birds from window crashes
9m 17s
Every year in the United States, as many as a billion birds die while migrating. These birds aren’t being killed by climate change or toxic substances in the air or water, but by collisions with glass. For our ongoing series “Saving Species,” John Yang reports on an effort in Philadelphia to reduce the carnage.