Sunday, February 26, 2006

Questioning the Luneau audio

I'm wondering why the fleeing "Ivory-bill" in the Luneau video evidently makes no audible sound.

Other bird sounds are heard loud and clear in the video, including a singing Prothonotary Warbler and lots of calls that may be from Blue-Gray Gnatcatchers. The "Ivory-bill" is supposed to be perched nearby for 20 or more seconds as the canoe approaches (with the trolling motor on), and evidently remains perched momentarily even after Luneau shuts the motor off. No kent calls are heard.

Then the bird flushes at a distance of 20 meters. Remember, Tanner said this (the bold font is mine):
The wing-feathers of Ivory-bills are stiff and hard, thus making their flight noisy. In the initial flight, when the wings are beaten particularly hard, they make quite a loud, wooden, fluttering sound, so much so that I often nicknamed the birds 'wooden-wings'; it is the loudest wing sound I have ever heard from any bird of that size except the grouse.
On Cornell's web site, you can listen to this existing recording of the initial wingbeats of an Ivory-bill flushing from a tree--coincidentally, these wingbeats are at a roughly similar frequency to the initial wingbeats of the Luneau bird. (By the way, note that the Luneau bird's wingbeats appear to quickly slow to less than 8 wingbeats/sec).

If you look at the silent video Cornell offers in their online Luneau video defense, you can see that Robert Henderson (in the front of the canoe) doesn't react as if he's heard any loud wing sound.

I can hear the originial Luneau audio because I shelled out the money for the DVD here. Online, you can hear the Luneau audio somewhat when John Fitzpatrick plays the Luneau DVD about a third of the way through his AOU plenary.

I think Cornell should make the Luneau video AND audio available as part of their online Luneau video defense. I think they should also address the issue of the missing loud wingbeat sound.


Bill Pulliam said...

I've wondered about the audio too. I can understand leaving it off of web versions to save bandwidth (we on dialup have a slow enough time with these videos already). But it does seem they could offer a large version with audio for the patient and broadband downloaders. Even if there is nothing on it, I'd like to hear it for the "total exerience"

Anonymous said...

Wingbeats, wing size, white on wings or not! Those are the "Million Dollar" or should I say "Millions of Dollars" question.
Yes, we have this video to look at, but now we have a second video to look at also. From what was released in Cornell's report, video & stills were taken of these Abnormal Pileated's. It would be very interesting to have this video to compair up against the video we have now. Would the "New" bird show white on the wings when perched on the tree, would it show white when flying off, what is the pattern of the wing beats on this new bird, and if audio is also on this video, what would be the sound of the wing beats of this bird that is 100% NOT an Ivorybill.

I feel this would a study well worth the time!

Anonymous said...

See, though, that would be science and NOT public relations. As a scientist I would show EVERYTHING that either adds to or detracts from my analysis. I would not just pick the pictures/videos that agree. As the director of a lab that is dependent on donated money, maybe I would handle it differently.