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rbgarr
02-01-2010, 01:42 PM
http://www.latimes.com/news/local/la-me-whale1-2010feb01,0,6269463.story?track=rss

switters
02-01-2010, 03:13 PM
1. Proof that the earth is getting warmer and is caused by co2
2. While whales are intelligent they are a bit behind human beings in terms of development and have only recently discovered Barry White.
3. Paul Watson can not hear high pitches.
4. Good news, but it sounds like some very optimistic conjecture.

I hope it is 4,

TomF
02-01-2010, 03:28 PM
Puberty?

Lew Barrett
02-01-2010, 09:20 PM
I'd buy this if it were true that high frequencies carry further in water than low frequencies, but the opposite is the case. Low frequencies carry further in both air and water due to a phenomenon called "Absorption." In both air and water, higher frequencies fall off at the cube of the distance.

Think of it this way: You know that annoying punk that pulls up to you with the Rap blaring out of his slammed Honda? What do you hear? The highs? Nah. The LF is what you get. Bad science wrong conclusion.

I wrote the original author of the article I read in the Seattle Times last week, but all she did was quote her own article back to me as proof.


Dear Ms. Schoof,

I read your recent article on blue whale songs with great interest both because I like whales and as a natural result of my professional knowledge of acoustics and sound propagation.

Although my expertise is not specifically in respect to sound propagation in water, the fundamentals indicate that low frequency sound (long wavelengths) travels further in both water and air....not the inverse as would seem to be suggested by your article. Here is some readily available support for that although there is much more available:

http://www.physicsforums.com/archive/index.php/t-63496.html

Given that fact, the notion that whale populations are singing lower songs because the whales are "closer" and therefore can afford to sing lower tones is patently in error as the basic hypothesis is incorrect. Low tones travel further, not the inverse, which if anything, might suggest that the whales are making an effort to reach out a further distance. I don't wish to draw this as a direct hypothesis as I am not a whale researcher, but you get the point. The basic idea that a shift to low frequency tones suggests that populations might be on the rise is not supported by the physics of sound propagation in water.

Thank you for taking the time to read my letter.

Lew Barrett


Low frequencies travel further, so what conclusion would you draw? I wouldn't say things are getting better for the Blues based on this evidence alone. In fact, I'd be more inclined to draw the opposite conclusion.

Michael D. Storey
02-01-2010, 09:41 PM
I would suggest that perhaps whale noise has not been listened to long enough to know if this is part of a cycle, or if it's like a teenager in the shower. I get the lower frequency travels best thing. Elephants, too.
This whale thing is good to know, because of an abiding interest in most things from the sea, but my unprofessional mind would be slow to draw a conclusion just yet.

Lew Barrett
02-02-2010, 11:35 AM
I agree with you there Michael; I am not a marine biologist with a specialty in whale songs.

Without making too much of the whales' motives though, it remains clear tp me that if they drew these conclusions based on their perceptions of sound propagation, they are in opposition to what is known about how sound moves through a dense medium like water. Lame. And just as lame on the part of the press....and I'm liberal in this respect :D

rbgarr
02-02-2010, 01:51 PM
I recall reading a theory that there are particular places/zones and depths of the ocean where communication between whales at low frequencies over thousands of miles is suspected.

Lew Barrett
02-02-2010, 03:09 PM
I recall reading a theory that there are particular places/zones and depths of the ocean where communication between whales at low frequencies over thousands of miles is suspected.

That would be my understanding too. There's also been a lot of press about naval sonar interfering with whale songs (communications) and although (if I recall....and this is from memory) civilian sonar is usually quite (relatively) high frequency (which probably is one reason why it has limited range) I don't know what frequencies the navies use. Probably many depending on tasking. Anyway, the whales have traditionally communicated at what is considered to be low frequency, although their range is remarkable....subsonic to supersonic. I'm not sure what the "brilliance" of this discovery is or who has promulgated it, but I don't trust it's conclusions one bit...or at least based on what I've read in the west coast papers.

It would be nice if somebody who knew which end was up came along to explain. In that persons absence, I say "hooey!"