Drumming Ruffed Grouse
To defend their territory from other males and to advertise their presence to females, male Ruffed Grouse don't vocalize -- they drum. The birds carry out this 10-second display year round, with peaks during the spring, The male grouse flap their wings forward and backward up to fifty times, creating miniature sonic booms with each flap.
Wanna hear this sound in person? Visit aspen-dominated forests throughout northern North America. But get there early: drumming is most intense a half-hour before sunrise.