“The Common Nighthawk (Chordeiles minor) typically gives a nasal 'peent' in flight, but during the breeding season the males will make this unearthly 'booming' noise (@ 12s in the recording). The sound is entirely mechanical, made by flexing the wings in a steep dive and forcing air through the wing feathers. This display is mostly done to impress females, but sometimes also to intimidate intruders (me in this case).” – Jacob Saucier, Division of Birds #SummerRoadTrip #Playlist | Smithsonian Nat