Blue whales align the pitch of their songs with extreme accuracy, study finds

Aug 02, 2010
Photo: Fred Benko - National Oceanic and Atmospheric Administration (NOAA) Central Library. (via Wikimedia Commons)

Blue whales are able to synchronize the pitch of their calls with an extremely high level of accuracy, and a very slim margin of error from call to call, according to a new study of the blue whale population in the eastern North Pacific. Results were published in the Journal of the Acoustical Society of America. The authors suggest that the uniform pitch used by blue whale populations could allow individual whales to locate potential mates by swimming toward them or away from them.

"Blue whales in a given population have been observed to align their to a common value, but we have now been able to determine just how accurately they are able to do so," said Roger Bland, professor of physics at San Francisco State University.

Bland and colleagues analyzed recordings of 4,378 blue whale songs, off the California coast, and focused on the whales' B calls -- the long, sad moan that typically forms the second half of the blue whale song that is specific to the eastern North Pacific population. They found that the whales all produce the B call at the same pitch, at a frequency of 16.02 Hz, exactly four octaves below middle C.

"We found that blue whales are capable of very fine control over the pitch of their call -- both in reproducing their call at the same pitch every time and in synchronizing their pitch with others," Bland said.

The study found a remarkably small variation in pitch from call to call. In musical terms, the half-tone change of pitch between the notes C and C Sharp is a 6 percent increase in pitch, whereas the variation observed between the blue whale's B calls was a 0.5 percent change in pitch.

The authors suggest that there may be an adaptive advantage to the whales tuning into a common pitch. "If whales are so super accurate in always calling at the exact same pitch, then it's possible that they could be able to detect tiny shifts in other whales' calls caused by the Doppler shift," Bland said. The is the apparent increase or decrease in pitch that is heard when the source of sound is moving toward or away from an individual, for example the change in pitch heard when a vehicle with a siren passes by.

Previous research has suggested that the song is produced only by males, and appears to be sung when the whales are traveling. "Given that blue whales can travel up to 5 meters per second, it's feasible that females could locate calling males by listening for the changes in the male's pitch," Bland said.

Underwater recordings were captured at the Pioneer Seamount Underwater Observatory, 50 miles off the California coast, over a three-month period in 2001.

The study's results are consistent with recent research suggesting that blue whales across the world have decreased their pitch over the last few decades. "We found the frequency of the B call to be 16 Hz in 2001, which fits well with the downward trending curve that has been observed in previous research."

Explore further: For stable flight, fruit flies sense every wing beat

More information: "Frequency synchronization of blue whale calls near Pioneer Seamount" was published in the July 2010 issue of the Journal of the Acoustical Society of America. The paper is available online at: bayacoustics.sfsu.edu/rtcpier/… /JASMAN1281490_1.pdf

Related Stories

Blue whales singing with deeper voices

Dec 08, 2009

(PhysOrg.com) -- Blue whales, the largest animals on earth, are singing with deeper voices every year, but scientists are unsure of the reason.

Listening to the song of the toadfish (w/Audio)

Mar 25, 2009

(PhysOrg.com) -- Professor Roger Bland is listening in on one of the noisier creatures in San Francisco Bay, using physics to analyze the mating song of the toadfish. While fish don't have vocal chords, they ...

Blue whales found near NY, off their usual path

May 28, 2009

(AP) -- There's a monster lurking off the coast of New York. Experts in a Cornell University acoustics program said Thursday that blue whales have been positively identified in the area for the first time.

Lone whales shout to overcome noise (w/ Video)

Jul 07, 2010

Just like people in a bar or other noisy location, North American right whales increase the volume of their calls as environmental noise increases; and just like humans, at a certain point, it may become too ...

Mariners urged to look out for whales

Oct 01, 2007

The U.S. Coast Guard has warned mariners to take care to avoid hitting whales, after three whales were killed off the California coast.

Recommended for you

Why do snakes flick their tongues?

Jul 31, 2014

Many people think a snake's forked tongue is creepy. Every so often, the snake waves it around rapidly, then retracts it. Theories explaining the forked tongues of snakes have been around for thousands of ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

h0dges
not rated yet Aug 02, 2010
"whereas the variation observed between the blue whale's B calls was a 0.5 percent change in pitch"

That's twelve times smaller than a semitone change.
kevinrtrs
1 / 5 (3) Aug 03, 2010
I am glad that they have found this to be the case. Their diligence and efforts has been suitably rewarded.

Note that no amount of evolutionary speculation was required to determine these measurable parameters. They simply went out there and measured using whatever technique they'd refined to determine such minute variations in pitch.

Good application of science that doesn't need any bit of evolution to get in the way.

Stating how the whales managed to develop such fine control over pitch after evolving from a single cell, well, that is sheer speculation of the highest order. No one knows and no-one can know until God finally reveals it when He returns.
Yes, you can now flame me all you want.