Why do hummingbirds hum?

The sound that gives the hummingbird its name isn't a song or a call. Instead, that characteristic buzzing is a physical phenomenon created by the astonishing speed of its wings. As the tiny wings beat back and forth, they generate pressure waves, or vibrations, in the air. Our ears interpret these rapid vibrations as a low-pitched hum, similar to the sound produced by the wings of a large insect.

Depending on the species, a hummingbird can flap its wings anywhere from 50 to 80 times per second during normal flight. This rapid movement, often in a complex figure-eight pattern, allows them to hover with incredible precision, fly backward, and even upside down. The exact pitch of the hum can change based on the bird's size, its wing speed, and what it's doing—a hovering hum sounds different from the high-pitched whistle (Review) created during a dramatic courtship dive.

This unique, energy-intensive flight is essential for the hummingbird's survival. It enables them to access the sugar-rich nectar deep inside flowers, which in turn fuels their incredibly high metabolism. The hum is simply the remarkable auditory signature of one of nature's most impressive aerial acrobats at work.