Artificial light attracts migratory birds to cities, where they face a range of threats

Light pollution from urban areas has steadily increased and expanded, and with the advent of LED lighting, it is growing by as much as 10% per year in North America, as measured by the visibility of stars in the night sky. In our recent research, we found that the glow of cities and urban suburbs can strongly attract migratory birds, luring them to developed areas where food is scarcer and exposing them to threats such as collisions with glass buildings.

Every spring and fall, migratory birds travel to or from their breeding grounds, sometimes traveling thousands of miles. Along the ...