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IVORY-BILLS  LiVE???!  ...

=> THE blog devoted to news and commentary on the most iconic bird in American ornithology, the Ivory-billed Woodpecker (IBWO)... and... sometimes other schtuff.

Web ivorybills.blogspot.com

"....The truth is out there."

-- Dr. Jerome Jackson, 2002 (... & Agent Fox Mulder)

“There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.”

-- Hamlet

"All truth passes through 3 stages: First it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident."

-- Arthur Schopenhauer

Saturday, November 07, 2009


-- Update... --


Mike's newest clip is up here (thanks Emupilot for the heads-up):


But worth reading his 11-7 entry [http://www.fishcrow.com/winter10.html], where he's now discounting, on the basis of size, the clip which I previously considered his most interesting one (prior post). And I don't believe there's much chance the "gliding" bird clip will be reviewed as an IBWO-contender either. So that leaves just the "flushed" bird clip (I don't think it's determinable, but just my personal opinion), and now the new video, which once again has tantalizing frames, but also I think has significant issues. I suspect most will recognize the traits that are IBWO-like in this footage, so once again I'm really more interested in hearing from the skeptical side what is NOT IBWO-like in this bird, and what alternatives you favor (and no longer need to respond to the prior clip which I had focused on).
(Mike is altering his log entries BTW, and this could make it difficult/confusing to follow this story if you entered late and read other people's previous references to his various posts over the last few days, which he's now re-written.)
Again, I'm seeing less and less here to get excited over, but still willing to be convinced otherwise.
I don't qualify as a skeptic, but I tried to find positive identification of a Red-headed: red head, white rump, or white body. I don't think we ever get a good view of the rump. I cranked the saturation and couldn't find any red and I couldn't find a light body. That doesn't mean those features aren't there, for the same reason we may or may not be able to see the white wing linings.

Even if it can't be identified as confusing species, it doesn't necessarily follow that it is an Ivory-bill. That would take more than one distinctive feature, like white wing linings or perhaps confirmation that the white on the trailing edge of the wings extends onto the primaries. My impression is that the white trailing edge is too long for Red-headed, but I assume curvature of the wing can make that measurement tricky.
One emailer writes, "I'm having a hard time convincing myself it's not a Red-headed."

...and I concur; I believe white can be seen on the rump in a couple of frames, I just can't be sure if it's part of the bird or artifactual on my screen (head and tail better fit RHWO than IBWO as well IMO).
To my eyes both upperwing and particularly the underwing are not showing IBWO features, the structure doesn't look right to me, being too bull-headed and the rump / uppertail coverts area seems to show white/pale, noticeable towards the end of the Nov 05 clip when the wings look too dark overall on both surfaces too. Not what I was expecting.

Size and distance are not discernible for me.
A lot has been made of wingbeat frequency in the past. What do people think of Nov 05 clip?
11/5 video

There are some lighter areas in the chest and rump in some frames. The flap style to me doesn't show IBWO, its choppy and the bounding before it turns seems unusual, although that may be the way an IBWO or RHWO would react if it noticed something distant in a tree. That brings me to that turn, did that bird change course because it noticed some possible, perched predator in a tree (MC in tree)?

The bird may actually have been closer than perceived which can happen when one thinks IBWO but its a RHWO. Many of us have seen these types of things happen to ourselves.

It being ~ 0900, with the sun gaining some minor height may cause the wings to shadow a white chest in a bird swinging to the N with the light coming from the S. Why the white body of a putative RHWO isn't more pronounced when the wing is at the upstroke can be argued to be the subject's distance affecting video quality combined with the cameras meter adjustment to the dominating, lighter sky. Then again the light in the rump could be a reflection artifact as the sun seems to be shining, at least obliquely, on that area.

Trying to make a determination using basic morphology differences between Ivory-billed and Red-headed the body length to wing span ratio might be useful.

IB 19.5 to 29.5 .66 ratio
RH 9.25 to 17 .54

This is a 22% difference in the ratios.

Then the 11/5 tape was scrolled through and measurements were taken when the left wing was at its perceived apex to minimize foreshortening. The single wing screen measurement was doubled to get the wing span.

raw data inches, followed by ratio, and % (IBWO best near .66, RH .54)

13/32 41/64 26/41 .63
13/32 10/16 26/40 .65
15/32 41/64 30/41 .73
7/16 41/64 28/41 .68
29/64 10/16 29/40 .72
7/16 41/64 28/41 .68

This data has no adjustment for any actual foreshortening which should be more than negligible. Any compensation for foreshortening will increase the denominator and bring the ratio closer to RHWO. Wings are also curved and any adjustment for that will further favor a determination that this bird is a RHWO, but to what degree remains to be done if important/feasible (doubtful). If the video does not portray the light colored bill of IBWO than the body length could be longer than measured and that would cause adjusted results to be closer to an IB.

Body length foreshortening was assumed to be negligible although it may not be.

The way the wing span was measured could also be in error.

Anyway, great effort by Mike...and there are other opinions and vidoes posted that could move the ball around.

thanks F Virrazzi
What about the flap rate?
Mike has evidently concluded that the bird in his Nov. 5 clip is a red-headed woodpecker. I found it hard to see it is anything else.

He has also concluded that the bird in his first clip from Nov. 3 is too small for an ivory-billed woodpecker.
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