Comments on this post on Tom Nelson's blog, which intend to summarize the reasons why the Luneau bird has been conclusively demonstrated to be a Pileated, in fact sumarize why these reasonings are all fundamentally flawed:Arkansas duck hunters still skeptical
Some key claims (and their refutations) include:
1. The Luneau bird unequivocally displays a black trailing edge to the underwing; its seeming narrowness is a result of white bleed.
The Luneau images show black on the leading
edge of the bird's underwing as often as they show it on the trailing edge. Neither IBWO nor PIWO should show a black leading edge to the underwing. The "black trailing edge" is never more than one pixel wide, and is inconsistent. Ergo, the Luneau video does NOT clearly show a black trailing edge to the underwing. It is perfectly consistent with an underwing that has white at the leading and trailing edges. Artifactual black edges to bright areas are abundant in the video frames. On the second point, white bleed is not occuring prominently in the video. This is shown clearly by looking at the outlines of tree trunks where they pass in front of bright and dark areas in the background. Where they pass in front of white, they generally do NOT show white bleeding (which would indent their apparent edges); instead, they often show spurious black edges at the light-dark interface. Blurring of the underwing is a result of motion blur, not white bleed.
2. If frame 33 and 50 show an extended wing, the bird is a PIWO.
I agree that frame 33 and 50 probably show the hind portions of the underside of an extended wing. But this hind portion appear to be predominantly or exclusively white, even in frame 50 as it is eclipsed behind the tree trunk. Sibley's drawing that tries to make this a black-edged pileated wing shows an absurdly and unrealistically narrow black edge. And, even if you are going to blame this narrowness on white bleed, you won't get white bleed from the part of the wing that is behind the tree trunk and not visible!!! In frame 50 only a narrow fringe of the trailing part of the underwing is visible, yet the dominant color in this narrow fringe is still WHITE. So even this interpretation of these frames does NOT indisputably support a PIWO ID; indeed it seems to lean towards an IBWO ID.
3. Sibley, Kaufmann, and Bevier all have concluded the bird is indisputably a PIWO, and who are we to question them?
Sibley: His analysis of the video, as I mentioned above, shows a ridiculously narrow black trailing edge on the bird's underwing. White bleed may be invoked as a justification for this, except that white bleed is not much in evidence elsewhere in the video. Motion blur affects black and white equally. He also embraces the intermittent, teeny, and narrow black trailing edge, while dismissing the similar black leading edge as an artifact. And, he stops his sketches at the point where it starts to get difficult, where the bird begins to level and then rise relative to the line of sight, and the hypothesis that all the white is on the ventral wing surface becomes much harder to support. Most glaringly, he completely ignores the blatant fact that the wing postures he draws (with which I have no argument, my own sketches show similar postures) are entirely unlike the wing motions show in PIWO comparison videos. The PIWO videos I have seen show a quite consistent (flat!) wing geometry during the downstroke; the Luneau bird shows something very different.
Kaufmann: So far as I know, he has never given his reasons for stating the Luneau bird is a PIWO. An opinion not backed up with reasons is not something that needs be discussed in a scientific debate.
Bevier: He rules out IBWO based on what he sees as a PIWO-shaped black wingtip on the underwing. This is an interesting case, where the Luneau video is first described as very poor and showing no detail, then it is claimed that it shows a detail that rules out IBWO. The shape of the black area on the distal end of the rapidly moving underwing cannot be determined with any detail, given the motion blur and abundant spurious black edge artifacts. It can only be determined that some black area of about one pixel in extent occurs there. This is true for bith PIWO and IBWO. Bevier's smoking gun in fact is shooting blanks.
Who are we to question these authorities? Interesting statement from people who claim that mutiple ornithologists at Cornell and Auburn, the Arkansas bird records committee, and Science Magazine have all committed astounding errors. These gentlemen (S, K, and B) may be experts at bird ID, but are they experts at forensic analysis of crappy video? Experts are mistaken all the time, experts are just as much subject to group mentality, axe grinding, reputation salvaging (Sibley and Kaufmann published the first two "comprehensive" North American bird guides that left out the IBWO; they were among the few American bird experts who stepped forward and prominently declared the IBWO extinct, not just possibly or probably extinct), emotional responses (Sibley describes weeping with feelings of betrayal on first seeing the Luneau video and how crappy it was), etc.
Enough for now. Before you start telling me what an idiot I am, please be familiar with the full exposition of my own Luneau interptetations:Luneau postings index
And since apparently some of the people who read my blog are not good with details, I'll make this as obvious as I can:IN IVORY-BILL DISCUSSIONS I DO NOT APPROVE ANONYMOUS COMMENTS
The Luneau bird may not be indisputably an Ivorybill, but neither is it indisputably a Pileated. In fact, it shows several characters that are notably inconsistent with a PIWO ID. This is my conclusion. Yours may differ. Neither of us is infallible or omniscient.