The artificial lights produced by humans disrupt the migration of birds, often with fatal consequences, says biology professor Dan Mennill.
“Birds use stars to orient their journey between summer breeding grounds and winter feeding grounds,” Dr. Mennill writes in an article published Monday in the Conversation, which shares news and views from the academic and research community. “Birds are drawn to the artificial lights that occupy their airspace, and their navigational compasses are short-circuited by the unusual presence of light.”
He notes that well-lit high-rise building can kill hundreds of migratory birds in a single night, but house dwellers shouldn’t be too smug. Mennill’s research, using bioacoustics recordings of flight calls, revealed that even low-powered outdoor lights change the behaviour of migratory birds overhead.
Fortunately, he has a simple solution to propose: the flip of a light switch.
“In spring and fall we should turn off our outdoor lights at night,” Mennill says. “With the lights out, we can take the opportunity to stand outside and listen to the night sky. We’ll hear the sounds of a billion animals moving across the continent with less distraction from our light pollution.”
Read his entire piece, “Want to save millions of migratory birds? Turn off your outdoor lights in spring and fall,” in the Conversation.