Filed Under:

Scientists Pinpoint Source Of Antarctic 'Quack'

Play associated audio

For decades, researchers and submarine crews in icy waters off the coast of Antarctica have been picking up a mysterious quacking sound.

The "bio-duck," as its called, has been heard on and off since Cold War patrols picked it up on sonar during the 1960s.

"It goes 'quack, quack, quack, quack,' " says Denise Risch, a marine biologist with the National Oceanographic and Atmospheric Administration. "It has this almost mechanical feel to it."

Some thought it might be 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.

"The sound is very intense, it's very loud, so the thought was it's probably a larger animal producing the sound," says Risch.

As researchers gathered more data, a suspect emerged: the Antarctic minke whale. Not much is known about this particular whale. It's the smallest of the baleen whales; it's solitary; and it tends to stay very close to dense sea ice.

"That makes them quite hard to study too and that's also part of the reason why the signal has not been identified earlier," Risch says.

But last year, during the Antarctic summer, a team from Duke University was studying the behavior of these whales. Researchers attached an instrument package to one of the whales using suction cups; on board was a microphone. Briefly, in one of the recordings, was a muffled, up-close version of the quack.

"They don't sound alike, but the pulses are exactly 3.1 seconds apart from each other," says Risch.

The same as the quacking.

The frequency of the noise matches too. Risch and her colleagues published their work in the journal Biology Letters.

So, mystery solved. Well, sort of.

Scientists still don't know why or even how these whales quack.

Copyright 2014 NPR. To see more, visit http://www.npr.org/.

NPR

No Longer Omar: Actor Michael K. Williams On Lucky Breaks And Letting Go

Over the course of his career, Williams says he's learned to separate himself from his characters (like The Wire's Omar). In HBO's The Night Of, he plays a powerful prison inmate named Freddy.
NPR

#FoodPorn, Circa 1600s: Then And Now, It Was More About Status Than Appetite

A new study of old masters finds that capturing and showing off decadent and expensive meals is a decidedly old-fashioned practice. Like today's Instagrammers, it was all about projecting an image.
NPR

Sanders Supporters Boo As He Calls For Them To Vote For Clinton

"Brothers and sisters, this is the real world that we live in," Sanders tried to say over the noise.
NPR

Verizon Buys Yahoo For $4.8 Billion In Cash, Touting Gains In Mobile

The deal comes more than a year after Verizon paid $4.4 billion to acquire AOL; as part of Verizon, Yahoo will join the same division AOL currently occupies.

Leave a Comment

Help keep the conversation civil. Please refer to our Terms of Use and Code of Conduct before posting your comments.