Scientists Pinpoint Source Of Antarctic 'Quack' : The Two-Way For decades, a mysterious quacking "bio-duck" has been heard roaming the waters of the Southern Ocean. Now scientists say the source is a whale.

Scientists Pinpoint Source Of Antarctic 'Quack'

  • Download
  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript


For decades in the remote icy waters off the coast of Antarctica, people have been detecting a mysterious quacking sound. Crews on submarines heard it first. They called it the bio-duck. Now researchers writing in the journal Biology Letters claim to have identified the source of the noise.

As NPR's Geoff Brumfiel reports it comes from something a lot bigger than a mallard.

GEOFF BRUMFIEL, BYLINE: Submarines on patrol in Antarctica first heard a mysterious sound in the 1960s.


DENISE RISCH: It's really almost like a quack sound. So it goes: Quack, quack, quack, quack.

BRUMFIEL: Denise Risch is a marine biologist for the National Oceanographic and Atmospheric Administration. The quacks were regular and they went on for hours.

RISCH: It has this almost mechanical feel to it.

BRUMFIEL: Some thought it was a secret Soviet sub. But over time, they came to realize it was an animal. It got a name: the bio-duck. Although whatever was making this sound had to be a lot bigger than a duck.

RISCH: The sound is very intense. It's very loud. So the thought was it's probably a larger animal producing the sound.

BRUMFIEL: As researchers gathered more data, a suspect emerged: The Antarctic minke whale. Not much is known about this particular whale.

RISCH: It's typically solitary. You don't often find them in large groups. And they're unique in that they're mainly found in ice covered waters. That makes them quite hard to study too and that's also part of the reason why the signal has not been identified earlier.

BRUMFIEL: But last year, during the Antarctic summer, a team from Duke University was studying these whales' behavior. They attached an instrument package to the whale using suction cups. On board was a microphone.


BRUMFIEL: Briefly, in one of the recordings, was a muffled, up-close version of the quack.


BRUMFIEL: That may not sound like the same sound to you.

RISCH: No, they don't sound alike. But the pulses are exactly 3.1 seconds apart from each other.

BRUMFIEL: The same as the quacking. The frequency of the noise matches, too. So mystery solved, sort of, because scientists still don't know why or even how these whales quack.

Geoff Brumfiel, NPR News.


You can follow all of us here at ALL THINGS CONSIDERED on Twitter. I'm @nprmelissablock.

CORNISH: You can tweet me @npraudie and you can follow our co-host Robert Siegel @rsiegel47.

BLOCK: And ALL THINGS CONSIDERED producers are tweeting throughout the day with behind the scenes updates and upcoming stories. You can follow us @npratc.


CORNISH: You are listening to ALL THINGS CONSIDERED from NPR News.

Copyright © 2014 NPR. All rights reserved. Visit our website terms of use and permissions pages at for further information.

NPR transcripts are created on a rush deadline by an NPR contractor. This text may not be in its final form and may be updated or revised in the future. Accuracy and availability may vary. The authoritative record of NPR’s programming is the audio record.