Whales’ Lower-Pitch Sound Has Experts Guessing

[babylonsister]

Whales’ Lower-Pitch Sound Has Experts Guessing

DEEP BLUE Scientists say the call of the blue whale has dropped in frequency.

By BINA VENKATARAMAN
Published: July 29, 2008


The song of the blue whale, one of the eeriest sounds in the ocean, has mysteriously grown deeper.

The calls have been steadily dropping in frequency for seven populations of blue whales around the world over the past 40 years, say researchers at the Scripps Institution of Oceanography, the National Oceanic and Atmospheric Administration and WhaleAcoustics, a private research company. The scientists analyzed data collected with hydrophones and other tools and found that the songs, which they believe are by males advertising for mates, had lowered by as much as 30 percent in certain populations. Much of the song lies at frequencies too low to be detected by the human ear.

The study, though not yet published, has been reviewed by several experts in the field who, in interviews, called the global decline “dramatic,” “significant,” “convincing” and “unequivocal.”

Scientists cannot explain why blue whales from places as disparate as the northern Pacific and the Southern Ocean, which surrounds Antarctica, would drop the pitch of their songs. Each blue whale population has a distinct tempo and tone set to its vocals.

John Hildebrand, professor of oceanography at Scripps and an author of the study, said the drop might signal a rebound in the population of blue whales since commercial whaling bans began to take effect in the 1970s.

more...

http://www.nytimes.com/2008/07/29/science/29whale.html?_r=1&ref=science&oref=slogin

[BlooInBloo]

1. I think they're saying "Let's get it on."

[SpiralHawk]

4. I think they are asking humans to stop pissing in the Big Pond

Help!

[glowing]

2. Perhaps they are communicating to "off planet" beings who would like to

help us clean up our mess.. these whales are amazing.. they def. should not be hunted and killed.. Our understanding of the creatures we inhabit this planet with is by far wayyy too little.

[XemaSab]

12. Admiral

There be whales here... :o

[livvy]

3. Whale slang. n/t

[kirby]

5. Ricola... n/t

[LiberalFighter]

6. Hopefully cancer is not causing it.

[Javaman]

7. Maybe they got the...blues. ouch!

:rofl:

[eppur_se_muova]

8. One guess: they are avoiding frequencies filled with ship noises

Large ship engines/gears/props produce a lot of low-frequency noise. The whales may be adjusting their voices to be heard over the racket.

Years ago, Paul Winter (and the Winter Consort) released an album, "Callings", which featured the song of the blue whale on one track, "Blues' Cathedral", together with organ and contrabass Sarussaphones. The whale's call is played at natural frequency, then at double speed, then at quadruple, which raises the pitch two octaves. When the album was re-released on CD, they dropped the natural freq call (!!!), so the only way to hear it is to get the old LP. Most stereos/speakers will not handle these low frequencies (and you'd better have a good cartridge, too), which I'm sure is why it got dropped. I lived in an apt with counterweighted-sash windows, and with the volume high enough, the windows would "walk" up and down when the whale sang. It was really incredible to feel these ultra-low freq vibrations, as the call dived into the subsonic range, and know that they were created by a living creature. I hope someone captures that sound for an IMAX film (assuming they haven't already).

(One other song dropped from the CD: "Dance of Gaia", which featured some LOUD drum work. The two songs which would have benefited most from digital audio technology were two (of three) that got dropped to fit a double album on one CD!)

[tinrobot]

14. That was my thought as well.

They just want to talk and be heard over the noise we create.

[GliderGuider]

9. They finally hit puberty?

:hide:

[phantom power]

10. Change in fashion?

Their songs are essentially part of a culture. Our music, language, etc, changes over time, and the changes are easily measurable over generational timescales.

[Dead_Parrot]

11. They've entered the Barry White era? nt

[phantom power]

15. Yeah baby...

[XemaSab]

13. Maybe there are fewer whales spread father apart

and they need a lower pitch to communicate with one another? :shrug: