Myth Busted: Does a Duck's Quack Echo?

Duck calling, studio shot
Image Source / Getty Images

Across the internet, on email trivia lists, "true facts" Twitter feeds, and Facebook memes, you may come across the claim that "a duck's quack doesn't echo, and nobody knows why." 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 the quack is 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?

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 intriguing enough to research and/or test it.

  • Snopes.com has a long article debunking this myth. The authors point out that it would be strange for the duck's quack—and only the duck's quack—to possess such unique acoustic qualities that it produces no echo. After all, different duck species produce different quack sounds, and so do males and females. It would be highly unusual if none of these various duck sounds produced an echo.
  • Scientists at the Acoustics Department of the University of Salford in the U.K. went to the trouble of actually testing the quack of a duck named Daisy. The duck's quack, they found, did indeed echo under the right circumstances, such as when the duck was placed in a reverberation chamber. The difficulty, however, was that her quack was so quiet that the echo, in some settings, was almost inaudible. The scientists also noted that the quack is a "fading sound," which makes it somewhat difficult to distinguish the quack itself from the echo.
  • The TV show MythBusters also looked into this myth. Here's what the investigators 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 ducks quack too quietly to generate an audible echo outdoors. Both of these speculations are likely true.

    Trevor Cox, one of the scientists at Salford, said that in none of his "field experiments" could he "hear a clear, audible quack separate from the original call." He was studying the waterfowl around various rivers, canals, and ponds. Cox believes the absence of a reflecting surface—such as a bridge or cliff face—is the reason for the lack of an audible echo.

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