Wednesday, November 11, 2009

-- The Discussion Proceeds --

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A somewhat extensive post, that I largely agree with, over at IBWO Researcher's Forum from "PORCAR" regarding the possibilities for Mike's Nov. 5 bird (narrowed down to 3 woodpeckers for PORCAR). The one thing he doesn't address directly that I think can't be entirely ruled out (however unlikely it seems) is a mutational Pileated (or for that matter possibly a mutation of something else):

http://www.ibwo.net/forum/showpost.php?p=5286&postcount=1231

For the moment we seem to be headed into Luneau Land on this video, but maybe the fog will lift and there will yet be a firmer consensus.

Also, thus far very minimal response over at the "Frontiers of Identification" birding site to the Collins videos. Could be, as I surmised earlier, that no one is taking them very seriously there... or, it could be just the opposite, that some folks are viewing them so seriously as to take significant time to analyze and prepare their response. But if we haven't seen more analyses posted within another week-or-so, I suspect it is the former explanation.
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3 comments:

spatuletail said...

It is surely the former explanation.

Even PORCAR says: "The white that appears in some of Mike's Nov. 5 frames would seem to be a slam-dunk at minimum for not being able to eliminate Red-headed from consideration. In fact, many knowledgeable commentators have already concluded that this bird has to be a Red-headed based on some of these later frames."

EJS said...

I think some of the clips of woodpeckers posted earlier this year by Mike Collins are interesting for comparison with the Nov. 5 clip. His Sept. 15 clip shows a red-headed woodpecker, mostly in a glide with its wings folded; however one wingbeat is in progress as the bird appears on the left edge of the frame, and a second wingbeat occurs just before the bird is obscured by vegetation. The profile of the bird in several frames with the wings at or just below horizontal in the Sept. 15 clip appear to my eye very similar to certain frames of the Nov. 5 clip. The lighting in the Sept 15 clip is different; the white breast of the bird and some red on the head are evident.

FAV said...

The bird on 11/5/09 Pearl video is a Red-headed Woodpecker.

All you have to do is:

1) look at the body length to wing span ratios of all frames. They are almost all lying near the expected value for RHWO and not IBWO. You must adjust body and wings to foreshortening as applicable...don't forget to add back width (est 9.5 % of 2 times single wing length).

Also the bird is banking so as in most birds the wing opposite the desired banking direction can be quite vertical as it needs to push away at the direction of the potential predator in the tree. This is why you are getting the illusion that the wing is soooo looong in the early frames, the left wing needs to do most of the turning work and the other wing is a low counterbalance.

2) superimpose actual wing shapes of the subject species over the video wings in pertinent frames and almost all agree with the context of the wing cycle as being RHWO shape and size. Pronate the shapes as needed to get the right wing angle in relation to the body and long axis of bird.

3) plummage, multiple points, not listed here but obvious.

addtional plummage points

3a) lack of any hint of neck stripe
lack

b) lack of any hint of dorsal stipes

c) lack of proper neck shape

4) assuminmg bird curved to avoid viewer it had to do that at 800-900 feet rather than 350-450 feet. This point subjective, open to discussion, as all are.

5) take aspirin



thanks F. Virrazzi