Glass windows kill as many as 5 billion birds in the United States each year, but humans can mitigate the danger in a variety of easy, low-cost ways. Michaela Haas outlines some recommendations in a piece for Reasons to Be Cheerful.

The problem isn’t just with glass high-rises: according to Audubon experts, “low-rises with four stories or fewer account for more than half of bird collisions (54 percent), closely followed by residential structures (44 percent) and less than one percent at high-rises.”

Solutions include closing blinds or curtains to make the window visible or adding vinyl stickers to break up the reflection. “Putting vegetation or bird feeders close to windows is another deterrent, giving avian migrants a place to land instead of continuing at full speed toward the glass.” Experts recommend planting native vegetation that gives birds a place to rest and feed, particularly in urban environments where green space is scarce.

Light pollution also influences birds’ behavior, disorienting them. Turning off lights at night can help birds maintain their natural rhythms and stay on course during migration.