[The following is an exact transcript of this podcast.]
You probably missed it because you were sleeping. But one of North America's great natural phenomena happened over the nights of mid spring. After sundown, the skies filled with millions of birds all traveling nighttime legs of their journey north. These overnight flyways were discovered during World War II, when Doppler radar was developed. Anxious military officials sounded false alarms over phantom air raids, but soon realized they were just watching flocks of songbirds.
There are calls that each species only makes during these night flights. This spring, Jeremy Ross from Bowling GreenStateUniversity put microphones on top of buildings in Northern Ohio to record nighttime flybys. Birds use a chain of islands to hop from Ohio, across Lake Erie, to Canadian breeding grounds. Ross wants to know if proposed wind power farms might interfere. Using the volume of each call, Ross can calculate if birds are soaring safely above the blades of wind turbines. Something to consider with more wind power in the air.
—Steve Mirsky, with reporting by Adam Hinterthuer