Since many readers don't peruse the "comments" to previous posts I'll highlight this one that came in from Patrick Coin for the wider audience:
"Birder's World Forum, in this thread is reporting that Bobby Harrison is going to release a video of an IBWO from 2004 that has not been made public previously. It is supposed to happen at a conference on November 4 in Boston, Massachusetts. Harrison had mentioned this video in an article in the September, 2005 issue of Natural History, but I had not seen it mentioned in any other source."
cautionary note: while every new bit of evidence will of course be highly anticipated and poured over it will be surprising if this video piece adds much to the discussion or changes any minds. There had been rumors of this clip being released for quite awhile; the fact that it has taken this long, is even briefer/poorer than the controversial Luneau footage, and was never used by Cornell as part of their original published evidence, indicates how weak and inconclusive it must be (I'm not even clear if Harrison is releasing this on his own or has the full backing of Cornell in presenting it as evidence???). If by any chance video enhancing techniques have actually resulted in recognizable/suggestive film frames, then I suppose those techniques themselves will be called into question... At any rate, thanks Patrick for the heads-up notice.
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add-on: please see Patrick's further note below for link to and quote from Harrison's Natural History article -- I'll simply reiterate though that I chose not to cite this information back in Sept. because of doubts that the clip could carry any weight in the ongoing debate. We can all look forward to seeing (or hearing about) the film once released, just don't raise your expectations too high. It certainly won't satisfy those clamoring for a 'conclusive' photo/video.
3 comments:
Good idea to put that news up top, Cyberthrush.
Tom Nelson found the text of the September, 2005, Natural History article on the web, just the text. In that article, Harrison describes his interpretation of the video, and I'll go ahead and quote the description of what the video shows:
During one of my encounters, on September 4, 2004, I managed to capture an ivory-bill on video; as of this writing, that recording of the bird has not been widely released. Although it is brief and of poor quality, it shows an ivory-bill flying past a decoy that I had placed on a tupelo tree to attract a living counterpart. The bird is seen flying away from the camera at an angle of about forty-five degrees. Although the bird is behind foliage throughout most of the video, it is visible in an opening just before it passes out of the frame. Frame-by-frame images bring out the wing pattern of an ivory-billed woodpecker.
During the flyby, which lasts just a quarter second, the wings flap three and a half times, or roughly fourteen beats a second. In real time the wing beat appears to have a shallow range of movement, but the actual stroke is deep, covering an angle of at least 120 degrees. A frequency of fourteen wing beats a second explains why the wing movements I have seen appear rapid and shallow when the bird is in powered flight, and the high frequency also accounts for the description in the historical literature of the ivory-bill's pintail-like flight. Fourteen beats a second is too fast for the eye to see, so fast that the wings appear to quiver instead of flap. The movement creates the illusion of a shallow range of movement during powered flight. The video also shows a second flyby, thirty-three seconds after the first one, suggesting that the ivorybill was responding to the decoy.
Note that he says the video is "of poor quality". For comparison, he says the Luneau video of "...April 25, 2004, is not absolutely clear, at least not to the average viewer."
I've compared some of the statements in Bobby Harrison's article, Phantom of the Bayou, Natural History, Volume 114 #7, September 2005 pp.18-24, 52, (available on-line here) with statements in The Science paper of 28 April 2005--that describes the Arkansas sightings of IBWO. For clarity, quotes from the Natural History article are in italics, from the Science paper in bold.
It had a long neck, and the head--it had a red topknot that came to point, and it had a big white bill--it looked real cartoonish. Gene Sparling, a kayaker from Hot Springs, Arkansas, was on the phone, eagerly describing his encounter with a woodpecker on February 11, 2004, in the Arkansas bottomlands. …I had never heard anyone use the word "cartoonish" to describe an ivory-bill, but it was perfect.
Comment: To me, Pileated and several other woodpeckers also look "cartoonish"--they have bold patterns and jerky movements. I can't see that as unique to the Ivory-billed Woodpecker (IBWO).
From the 28 April 2005 Science paper:
11 February 2004 sighting. Field marks noted by G. Sparling were the bird's unusually large size compared to pileated woodpecker, peculiarly pointed red crest with black anterior edge, long neck, and extensive white on lower half of folded wings showing slight yellowish tinge along edges "like parchment paper."
Comment: There is no mention that Sparling noted the white bill in the Science paper, of which Harrison is a co-author. Why does this very important detail show up in the Natural History article by Harrison, but not in the scientific paper describing the discovery?
Later in the Natural History article, Harrison describes a close encounter with the Ivory-bill:
Even before making the video, [IBWO fly-by of a decoy, mentioned in another post] I had spent much of the summer of 2004 in the swamp, coping with scorching heat and swarms of mosquitoes. Yet, despite the discomforts, I was happy to be there, because on June 9, 2004, the misery paid off. On that date I saw an ivory-bill swoop from one tree to another, a distance of sixty-eight feet. Its wings were extended, and never flapping.
Summary of this from Science paper: 9 June 2004 Harrison saw a large woodpecker flush from near the base of a bald-cypress, Taxodium distichum, about 15 m in front of him, and with naked eye he noted broad white trailing edges to wings, especially visible as the bird swooped upward to land;
The Natural History article continues with more details of this sighting:
I had a clear view of the bird from behind as it swooped upward to land. The white secondaries of each wing were clearly visible, separated by the black back of the bird, and they reached all the way to the trailing edge of the wings. I could easily see the bird's black tail, back, neck, nape, and crown. The nape came to a point and seemed to have a tonal value darker than the neck and crown. A female? That was my first thought.
From the Science paper, in the analysis of the Luneau video:
Ivory-billed woodpeckers have a pair of longitudinal dorsal stripes that approach one another on the middle and lower back (Fig. 2), producing a white area visible on a dorsal view of a fleeing bird. Pileated woodpeckers have lateral white marks on the sides of the head and neck, but lack any trace of white on the dorsum.
Comment: Again, as in the February 27, 2004 sighting by Gallagher and Harrison, the observer(s) had a clear view of the bird's back and did not note the white stripes, which should be visible. Harrison says black tail, back, neck, nape, and crown. The white on the dorsum was allegedly visible on the Luneau video but not visible to an observer at 15 meters? Harrison was close enough to see that the crest was all dark, but did not see bold white stripes on the back of the bird? This inconsistency has been noted by others, but it really struck me when I read the account in Natural History closely.
I don't know about other readers of this discussion, but I am bothered by the inconsistencies of the field reports. A lot hinges on just a few things here.
Another inconsistency in the reports--I did not even notice this at first--a reader at birdforum.net noticed this:
Natural History: On [June 9,2004] I saw an ivory-bill swoop from one tree to another, a distance of sixty-eight feet. Its wings were extended, and never flapping.
Summary of this from Science paper: 9 June 2004 Harrison saw a large woodpecker flush from near the base of a bald-cypress, Taxodium distichum, about 15 m in front of him, and with naked eye he noted broad white trailing edges to wings, especially visible as the bird swooped upward to land;
In the Natural History article, the bird was said to swoop, not flapping its wings. In the Science paper, it was said to flush from the near the base of a bald-cypress. Surely it must have flapped if it was near the base of a tree to gain altitude. Perhaps it was just a choice of words. Perhaps by "near the base", Harrison meant more "on the trunk" as opposed to up near the top? I'm really not trying to pick this stuff apart, but altogether, this seems a bit odd.
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