For Anyone Who's Been Told That a Duck's Quack Doesn't Echo ...

Duck calling, studio shot
Image Source / Getty Images

Across the Internet, on email trivia lists, "true facts" Twitter feeds, and Facebook memes, you'll find the claim "a duck's quack doesn't echo, and nobody knows why." Please note that you won't find this claim made in any scientific journal or textbook. 

The logical question is: Why​ wouldn't a duck's quack echo? What could possibly be so unique about the sound a duck makes, and how it makes it, that it's exempt from the physical laws that apply to every other such sound, e.g., a dog's bark, a cat's meow, a cow's moo, etc?

The obvious answer is -- nothing. Nor does anyone who makes this claim about ducks' quacks ever attempt to explain how it could be.

How Do We Know This Claim Is Untrue?

Quite a few myth busters have found this claim to be intriguing enough to research and/or test it. For example:

  • Snopes.com has a long article debunking the theory.
  • Professors at the Acoustics Department at the University of Salford in the UK went to the trouble of actually testing the quack of a duck named Daisy. Daisy's quack, they found, did indeed echo under the right circumstances. The difficulty, however, was that her quack was so quiet that the echo, in some settings, was almost inaudible.
  • MythBusters TV show tested this theory. Here's what they found: "When examined by an audio expert, it was found that the echo was 'swallowed' by the original quack, due to the very similar acoustic structure between the quack and the echo. Because of this, it may be difficult to tell where the quack ends and the echo begins." 

    Why Might a Duck's Quack Be Inaudible?

    Acoustical engineers have empirically demonstrated that a duck's quack does, in fact, echo. They have also ventured a few explanations as to how beliefs to the contrary might have arisen in the first place — for example, the fact that ducks aren't typically found near sound-reflecting surfaces, or that perhaps ducks quack too quietly to generate an easily audible echo outdoors.

    In any case, using an echo chamber and standard recording equipment, engineers have successfully captured the echo of a duck's quack.