Most songbirds migrate at night, using a combination of environmental cues, including stars, to navigate. Artificial light can confuse nocturnal migrants, causing them to collide with lit structures, particularly tall buildings.

There are numerous examples of extensive bird mortality (thousands of birds) due to nighttime collisions with lit buildings.

It’s simple. Dark skies are safer for birds. Turn off or dim non-essential lighting during migration periods (April/May and September/October) to enable birds to migrate without distraction. You’ll save energy and money, too.

To learn how you can make your nighttime sky better for birds, check out the Five Principles for Responsible Outdoor Lighting from DarkSky International.