One night last October, an estimated 1,000 to 1,500 birds died in a three-block radius in downtown Philadelphia in a mass-collision event.
At night, the artificial lights of a city skyline can cause birds, who rely on the moon and the stars to find their way, to become disoriented and ultimately crash into building windows where they might see the reflection of the sky or trees. That’s why Philadelphia is taking action to prevent these collisions.