Research is showing that our porch and security lights are major causes of insect decline. Many insects are drawn to light, but artificial lights can be fatal to them. According to one study cited by Smithsonian Magazine, “It’s estimated about one third of the bugs swirling around those lights die by morning, either by being gobbled up by predators or simply from exhaustion.” Dramatic declines in insect populations have raised alarm bells in recent years. And all species, including humans, that rely on insects for food or pollination are directly impacted by this insect decline.
Bright outdoor lights can also have a devastating impact on birds. Up to 1 billion birds die from building collisions each year in the United States , and according to several recent studies, bright lights in big cities are making the problem worse. Every year, billions of birds migrate north in the spring and south in the fall, the majority of them flying at night, navigating with the night sky. However, as migrating birds pass over big cities, they can become disoriented by bright artificial lights and skyglow, often causing them to collide with buildings or windows. The schedules of migratory birds are also based on seasonal cues. Artificial lights can cause them to migrate too early or too late and miss deadlines for nesting, foraging and other behaviors. And, according to the National Audubon Society, when lights throw birds off their migration timetables and paths, fatalities often occur when birds waste energy “flying around and calling out in confusion. The exhaustion can then leave them vulnerable to other urban threats.”