Thursday, March 19, 2009

Openness, Fakery, what not

There are some strange things being said in the blogosphere about openness and secrecy as pertains to the Woodpecker Incident from the Undisclosed State. It needs to be made clear that all the data that was put up by Gary Erdy and Steve Sheridan was their own private property, collected (and in one sad case fabricated) using their own equipment and their own uncompensated time and effort. No government agency or other institutional entity has any jurisdiction over or rights to any of it; it is entirely Gary and Steve's to do with as they please. I don't know why anyone would think that the Feds or State or anyone else even had the right, much less the responsibility, to reveal and distribute this information any more widely than Gary or Steve gave them permission to. It was shared with various people, private, state, and federal, under agreements of confidentiality. It became public when Gary and Steve chose to make it so, and not a moment before then. The only request from any government was to omit mention of the location or names of reviewers who might give away the location. As for anonymity of reviewers, that is standard practice in peer review. This is not a question of academic, government, or scientific openness; this was purely about the intellectual property rights of private citizens.

Edit: Folks from the state DNR tell me that there were some stronger and more official arrangements between themselves and Gary and Steve, including agreements to share information, notify of intent to publish, participate in a review process before publication, as well as permission to install cameras and carry out research in a State Natural Area and loans of some equipment. There may be some disagreements among the parties involved as to exactly what compliance with these arrangements would have looked like and if it was in fact achieved; much of that is beyond the point I was making. My point is that all involved in general deferred to Gary and Steve as having first priority in the handling of the images that they collected (and created... though that part was not known even to Gary), and in most ways respected and deferred to their ownership rights. The gov't agencies did not employ a strong hand in attempting to control what Gary and Steve did with their own data, and in my opinion this was the correct approach.

I also noted with amusement someone who credited me with being right on all the major ID points; well, other than having missed that the image was entirely fabricated. That last bit is quite a whopper, however; more on that later. But anyway, that isn't even true. I, like many other people, maintained that the neck stripe was not correct for a Pileated; we were all wrong. The bird does not have a dorsal stripe hidden behind its wing, as I suggested was possible; it has no dorsal stripes to hide. What I was "right" about was that ultimately the bird does not reconcile neatly with any species; this was in fact the majority conclusion of the knowledgeable birders who saw this image before the forgery became known. Only loud voices online (seemingly many from people who know little about birds per se) gave the impression that there were any kind of definite opinions as to the bird's ID; most bird people agreed it was not conclusively identifiable from what could be seen. And now we know exactly why.

As to missing the forgery; sadly, forgery is missed all the time. Careful fakery can be hard to detect simply from the properties of the fake item. Indeed, images and objects are fabricated and falsified on a massive scale all the time in our our society; we call it entertainment. Once forgery it is uncovered the clues may become obvious in hindsight; but in real time the world is a different place. It is also worth mentioning that the people who eventually pushed Steve to admit his forgery were the same people who had been involved in this process all along. As the size and distance data (collected and analysed by all these same "incompetent experts") became increasingly troublesome, the questions for Gary and ultimately for Steve became more and more difficult to sidestep, until finally the truth came out. Publicity pushed this process forward, but I don't believe the online ranting actually contributed one single teeny bit of information that led any closer to finding out the real situation here. I in fact warned Gary weeks before he revealed the information on their website that the distance numbers, as presented, could cast doubt on the veracity of the image. We all expected new numbers to resolve this conflict; instead they verified it, doubt was cast, and secrets revealed. All of which happened through the exact same channels, and among the exact same cast of characters, as every other stage in this process.

On beyond the technical details of what might or might not have been examined in this case, I think there is a bigger lesson that underlies the problem here. I for one, and probably most people who looked at the forged woodpecker image, fell victim to logic and reasoning. It simply made no sense to fake an image, risk so much, and still leave the result so ambiguous. Hence we were not as worried about the risk of forgery as we should have been. The argument was sound, except for one flaw. We assumed implicitly that someone who would fake an Ivorybill image would do so logically and rationally. But clearly this is not true. Rationally someone in Steve's position would never take the risk of faking an Ivorybill image, good or bad. No one would. Even if you were out for money, the payoff is likely to be small and the shame from exposure great. Far more lucrative ways to get money dishonestly exist. So, if an Ivorybill hoaxer is not going to be motivated by reason or logic, ergo, reason and logic have no bearing on whether evidence is likely to be real. Steve's forgery made no sense, still makes no sense. We were correct to believe that it would be nonsensical to have faked that image. We were wrong, however, to conclude that this meant no one would do it. As we should have remembered, rationality is often a minor aspect of human nature.

Wednesday, March 18, 2009

Steve Sheridan admits forgery

I have not checked the blogosphere or my e-mail to know how widely this is already known; apologies if this is already old news.

Steve Sheridan has admitted that his claimed photo of a mystery woodpecker from 2007 is a forgery. It does not appear that Gary Erdy knew of or was in any way complicit with this forgery. The image of the background bird was altered and pasted in to the photo; there was never more than the one Pileated in the frame. The source image was a Pileated Woodpecker, to which he add the white shield. Evidently the flood of new information confirming the irreconcilable conflict between the distances from camera to each bird and the apparent relative sizes of the birds finally compelled him to confess that the image was manipulated.

I have more sympathy for Steve than most of you would expect, considering how harshly I have dealt with other suspected forgers. But Steve confessed and repented willingly, and never hurled accusations, insults, and other vitriol at those who questioned his veracity or asked straightforward questions.

Obviously this is now entirely moot as regards the significance of this image per se. However it has many repercussions for the past and future, especially with respect to data from other private, unaffiliated searchers, as well as the vetting and verification of this data. I will have more to say about that at some point in the future; we ALL dropped the ball at various points this time.

Sunday, March 15, 2009

Context

An interesting bit of information:

Of all the dozens of posts to this blog in the archives over the years, there is one entry that steadily draws new hits in spite of being nearly three years old. It's not a lot, only a couple a day; but still it is the most regularly read piece I have posted here. No, it's not any part of my Luneau video analysis, in spite of that being linked to prominently in my sidebar. It isn't in fact any of my woodpecker posts; nothing about sightings or blurry photos or numbers games or any of my diatribes against our favorite Minnesotan. Those all had their day, drew their streams of comments, then they passed into the dusty unread backwaters. No, the one essay that still draws visitors on a regular basis is "The Pastured Poultry Scam". This bit is about chickens, responsibility, sustainability, honesty, and marketing; it addresses how we, our own species, live in the world. There's not a woodpecker in it.

Occasionally good to remember that the topics that consume the minds of we birders are rather far off on the fringe of mainstream society, even within the blogosphere.

Saturday, March 14, 2009

Madness, indeed

NOTE: The image in question is now know to be a forgery.

The problem with Steve's Sheridan's 2007 woodpecker photo is not so much that it is too low quality to get meaningful information out of it. As bad bird photos go, it's not actually that hopelessly bad. There are quite a few features of the bird that seem to be real that can be gotten from it. The problem is that they do not make sense. There is no ID for this bird that does not require some hand-waving, some skirting around issues. For the most popular hypothesis, a Pileated, we have a neck that is wrong, and have to explain the white below the black as anomalous plumage, illusion, or neck-wrenching and gravity-defying contortions. For the most exciting hypothesis, where are the dorsal stripes? Is the red on the head right? For the least tenable ID, the Red-headed Woodpecker, we have all sorts of problems with shape and plumage. Curiouser and curiouser. Better measurements for the distances involved should rule out one or two of these options; however, if they leave the Red-headed as the "only" option I still don't think I will accept that and will be compelled to examine previously unexplored avenues.

Wednesday, March 11, 2009

Proof and Probability

NOTE: The image in question is now know to be a forgery.

This is expanded from a comment I left on Cyberthrush's blog.

There is a fundamental reason why, in all likelihood, it will never be possible to absolutely rule out a Pileated Woodpecker in the case of Steve Sheridan's 2007 Mystery Woodpecker Photo. The white shield may be very unlikely, the appearance of the neck may be just as unlikely, but you have to consider the phenonenon of preselection. This image has been singled out from an untold number of other shots of large crested woodpeckers, accidental and intentional, precisely because of this unlikely confluence. It is not a random selection. So, even if we were to conclude that each of those events had, say, a 1:1000 chance, so the combination has a 1:1,000,000 chance... but there might have been 1000 or even 10,000 images of Pileateds taken over the last several decades by people knowledgeable enough to single this out. We really have no idea of that number. Even if it is as low as 1000 shots, our odds are down to 1:1000 for this bird; if it is 10,000 shots we're down to 1:100 odds on this bird. In reality we don't know anything about these various numbers other than that they are all pretty large. If the photo showed a visible dorsal stripe, then the triple coincidence would become so much more unlikely that even the preselection effect would be overcome in the judgement of most reasonable reviewers, I suspect. This is especially true when you consider that it is much easier to imagine leucism creating a large patch of white flight feathers than a narrow strip of white mantle feathers. But we don't have a visible dorsal stripe, so I don't really think there is any way anyone will ever push this bird past the barrier for being identified conclusively as an Ivorybill. It is still intriguing discovering how close it might get to that wall! And, in that gap between likelihood and scientific certainty is where the realm of personal beliefs, feelings, and opinions is found. Thus we have, and will probably have more, people who personally feel this bird is an Ivorybill, and get a thrill from that, but will also state that scientifically they feel that a very odd Pileated photo can not be conclusively ruled out.

And there is nothing unscientific about that.

Tuesday, March 10, 2009

How a bird's neck works

There seems to be a need to clear up some misunderstanding here about how a bird's neck "stretches." A living bird's neck does not stretch; a bird with a stretched neck is a dead bird. Below is a generalized avian skeleton, linked to from Enchanted Learning (thank you, Google!):



And here is a hummingbird skeleton, linked from Hilton Pond Nature Center:



Notice how the neck is held in a curve. To "stretch" the neck, this curve is straightened. To "retract" the neck, this curve is tightened. You can of course see this much more obviously on herons; it works the same way on all birds, the feathers just conceal the process more. Just like on a turkey or chicken neck, the skin is tight up against the narrow bands of strong muscles; it is not baggy and stretchy. So, when the neck is "stretched" there is not much actual stretching happening. There is no pull on the breast or mantle skin, the breast and mantle won't be drawn up into the neck. They are quite independent in their motion. If anything, there might be some slight compression of skin at the base of the nape, which could push the upper mantle feathers slightly rearwards if it affects them at all. There is also an absolute limit to how far the neck can extend. Once it is fully extended that's it; nothing the bird can do can make it any longer than that.

Why it is not a Red-headed Woodpecker

NOTE: The image in question is now know to be a forgery.

I also added this text to my previous posting about Steve Sheridan's Mystery Woodpecker. You should also read my post on how a bird's neck works if you still think that a "stretched" neck can somehow suck the black mantle up into the neck, resulting in a black neck rather than a red one.

Many people online are trying to make this bird into a Red-headed Woodpecker, in spite of the fact that this is a completely untenable ID. Even if accurate distance and size measurements confirm the bird's small size, I'm not sure that is the route to use to explain the mystery bird. The neck on a Red-headed Woodpecker is red, not black. There is no black or white on the neck at all to get stretched and distorted in to a white stripe on black background. The red goes down, uninterrupted, to the base of the nape and on to the upper breast. Those "white straps" on the shoulders are breast feathers protruding from under the folded wing. They will not stretch into a neck stripe no matter how hard you pull. Same with the black on the back; that is the bird's mantle and you can't stretch that into a neck either. Even if the white stripe is something other than plumage on the mystery bird, the neck is still quite plainly black, not red. So ignore the size and shape issues, stretch a Red-headed's neck until just before it snaps, and you still won't get a black neck. The mystery bird is not a Red-headed Woodpecker.

Saturday, March 07, 2009

From an Undisclosed Location...

This image is now know to be a forgery. The original post is retained here for reference and documentation.

Steve Sheridan's 2007 photo of what appears to be a large white-backed woodpecker in a cypress slough has finally been made public. If you have not yet been there, you should go look at the original website first, then come back here to read my discussion. I'm only going to focus on this one color image for now (called "Mystery Bird #3" at that site); there has been more activity than this in the area, including kents, double knocks, sightings, and interesting but of course inconclusive reconyx images.

This image has been circulating confidentially for a long time; it has been reviewed by State and Federal agencies and an array of external reviewers, many of whom are far more prominent than I. Obviously this image is not the "smoking gun" that proves beyond a reasonable doubt to all people involved that the Ivory-billed Woodpecker was still flying free and alive in 2007. But neither is it easy to just dismiss out of hand. Some of us have been scratching our heads in secrecy about this shot for well over a year; it's good to finally have it out in the open!

To summarize the story of the image, it is part of a long sequence of photos that were shot not of the mystery bird, but of the Pileated Woodpecker that is seen front and center in the full image. The photographer was not aware of the presence of the second bird until after the fact; it appears only in that one shot. No trace of it has been found in any of the other images. The images were not rapid-fire; many seconds elapsed between adjacent shots. For now I am not revealing the location; there is concern about disurbance to the site, where there are ongoing searches by private citizens and official agency crews. This info may be revealed in the near future; that is not my call to make. I will just leave it as having been taken in the United States within the documented historical range of the Ivory-billed Woodpecker.

After initial excitement, a substantial proportion of those who have reviewed this image have ultimately come down on a fairly negative, or at best indecisive, stance towards the possibility that it might represent anything other than a Pileated Woodpecker. No one, including me, has found any indications at all that the image is fabricated; indeed it makes very little sense that someone would go through all the trouble to fake an image so carefully, and yet still leave it so frustratingly ambiguous. There are two big questions that immediately leap out about it:

1. Is the "white shield" really part of the bird, or is it a trick of light or intervening vegetation?
2. Where is the "white suspender" on the bird's back? Or, 2a: Could a white back stripe be hidden by the wing?

Conversely, attempting to reconcile the bird with a Pileated, even if you allow for the possibility of an anomalous white shield, still runs in to two other basic questions:

3. Can a Pileated's neck "look like that;" i.e. show such a narrow white stripe and such a broad expanse of black between the white stripes?
4. Can a Pileated's crest look like that, so large and bright and bushy?

Jumping ahead to a preview of my answers, before I actually present the reasoning behind them:

1. The white shield is part of the bird.
2. A dorsal stripe could easily be obscured by the bird's wing.
3. It does not seem that a Pileated's neck can look like that.
4. Yes, a Pileated's crest can look like that.

So again spoiling my punchline, there are difficulties with either identification; however, other than the fact that the Ivorybill is such a phenomenally rare bird, that species is the easiest to reconcile with all the features in the image.

Now, to why I come to these answers:

1. Is the "white shield" real?

This has been one of the biggest items of discussion, and it is the point where I think that most reviewers have gotten it wrong. Many have decided that it is either a trick of glare off of the bird's back or some brightness produced by something in the foreground vegetation in front of the bird. Given the flat, shadow- and glare-free lighting in the rest of the image, the first option (glare off the bird's back) does not seem reasonable. Plus, the sharp line between the black and the white does not seem consistent with the glare hypothesis. Hence, I'll focus on the more serious possibility, that it is caused by something between the bird and the camera. Fortunately, we don't just have the image with the bird; we have a whole sequence of images both before and after the one shot in which the mystery bird appeared. I singled out three images: the shot with the bird in it (numbered 2), and the immediately previous and subsequent shots (numbered 1 and 3, of course). I have made two animations that blink different combinations of these images to try to resolve the matter of where this "white shield" is actually located. The images from which these animations were constructed are all copyright 2007 by Steve Sheridan; I have used them here with permission.

NOTE: These are not embedded videos or flash animations. The thumbnails link directly to .mov (quicktime) files. For the best effect, you should right click (or control click if using a one button mouse), download the linked file to your computer (not the thumbnail image, but the linked file). Then open the .mov file in your own media player and set it to play as a continuous loop so you will get the "blink" effect. This may seem inconvenient, but we're doing science here, not entertainment. Streaming media always results in image degradation; I want to preserve detail, not obscure it, even at the cost of convenience.

The first loop is a rapid blink of shots 1 and 3, the birdless frames. In between these two shots, the camera position shifted slightly, so the rapid blink gives a 3-dimensional effect that makes the various layers of depth in the image jump apart from each other:



Watching this, most people will see an actual 3D illusion; some people will not see the illusion directly but you can still resolve the depth dimension by looking at the differential amounts of parallax as the images jump back and forth.

I find four distinct depth layers: The bright sky in the background; the tree trunk; the branches and foliage in front of the tree trunk; and a very close hazy semi-transparent blur from vegetation right in front of the camera. The critical thing to note here is that all of the bright areas are background sky; there is no suggestion at all of anything bright in the foreground layers. They appear to consist solely of green foliage, dark twigs, and open spaces that allow the background to be seen.

In the next loop, I have added frame 2 (the bird) in the sequence, slowed the blink, and added cross-fade to smooth the transition between frames:



To my eyes, when combined with the information gotten from the first 3D loop, there's really not any doubt that the "white shield" is attached to the bird and behind the intervening foliage. It is larger in extent than the patches of sky in the birdless frames; the foreground twigs appear to be visible crossing in front of it; and it appears to block some of the dark tree trunk that is visible in the birdless shots. Going back and forth between the two loops, I see every indication that we have a white-shielded bird and no indications that the white is from any other source than the bird. I also does appear that the black spot to the lower left of the shield is part of the bird as well; if so it would almost surely be a wingtip as it seems unlikely any other part of the bird (such as the tail) could be in that spot and be consistent with the rest of the bird's visible posture.

2. Where is the back stripe?

Excellent question. The curve of the bird's wing is visible right about the spot where we would expect the dorsal stripe to be, so we can hypothesize that the dorsal stripe could be there but hidden by a wing that is cocked a bit dorsally; perhaps in preparation for flight. This is of course nothing but an ad hoc "just so" story; but it's still worth investigating whether it is possible. Unfortunately there are not many photos of living perched Ivorybills; all that do exist show dorsal stripes plainly visible where they ought to be. There are many more specimen mounts and photos of those mounts; Cyberthrush posted a collection of these images (and yet he swears to me he had no idea of the existence of the mystery photo when he did so). There are suggestions in those photos that the dorsal stripe could at least be somewhat obscured, but it's not entirely convincing.

Other than these limited comparisons, we do have many photos of other common species of woodpeckers that have similar dorsal stripes. I have gone through many still images of these, especially Lineated and Pale-billed Woodpeckers; and framed-through several videos of perched birds in motion of these species that are available online (google and youtube searches will turn up examples). A good collection of images of other Campephilus species can be found here. Search for "pale" in that gallery and you will get dozens of shots of Pale-billed Woodpeckers. A rather large proportion of the shots of perched Pale-billeds viewed from the side show little or no dorsal stripe; even more so when the bird is higher than the camera. So the answer here is that yes it does seem to be possible, perhaps even likely, that a perched ivorybill in that pose could have its dorsal stripe hidden behind the wing.

3. Can a Pileated's neck look like that?

It appears to me that the answer to this one is "no." I have looked frame-by-frame through multiple videos of Pileateds (youtube will provide you with many examples), and at many still photos. I have not seen a single shot where a Pileated shows such a broad expanse of black on the back of the neck bordering such a narrow neck stripe. On the other hand, this neck pattern is seen quite often in shots of Campephilus woodpeckers that have neck stripes.

4. Can a Pileated's crest look like that?

This seems to be a "yes." In my framing through videos I saw many cases of a Pileated showing what looked like a large bushy crest, due to blurring of various kinds and especially when the bill is pointed up. Usually the bill is also visible in these cases. A related matter is why doesn't the mystery bird show a black crown if it is an Ivorybill? Well, the red on the nape of a male Ivorybill extends quite far down, much farther than on a Pileated. So, for an Ivorybill to show a crest like that it could be looking straight away from the camera, not tipping its head up to expose the black crown. So the "big bushy red crest" is indeterminate; either species could look like that.

Other issues and items

A frequent additional question has been, why doesn't the bird's back appear any darker than that of the Pileated (Ivorybills have darker, glossier backs than Pileateds)? However, in the quick blink animation you can see that there is some very close foliage completely out of focus casting a greenish translucent haze over a large area that includes the spot where the bird appeared. Pixel sampling of the white and black on the bird indicates a lot of green in both. Conversely, the Pileated in the same frame appears to be in the clear, and its black tends more towards the reddish-brown. Different lighting, different circumstances, different intervening space; I don't think you can really compare these colors between birds. As a revealing exercise, if you take the original image, showing both birds, and use photoshop or some similar application to increase the color saturation to psychadelic levels, you get an interesting result. The black and white parts of the mystery bird almost all go quite green; the black on the foreground Pileated goes to black speckled with bits of red and green. Intriguingly, the upper part of the mystery bird's black back does not go green; it becomes a deep blue-black color. Fascinating.

A final issue that came up is the size of the bird. Gary Erdy reported measurements of the distance from the camera to both birds. If these measurements are taken at face value, the "mystery bird" appears to be too small to even be a Pileated, much less an Ivorybill. Rather than following this line of reasoning to its surreal conclusions (the bird is an inconceivably contorted Red-headed Woodpecker?? This seems utterly impossible), it is simplest to question the accuracy of the distance measurements. They were made with a laser range-finding device intended for golfing. The odds seem very good that it could have been thrown off by intervening vegetation and produced inaccurate measurements, especially for the distant bird through many layers of forest. There is also the possibility of mistaking the tree on which the bird was perched. Given these problems, until a physical measurement is made on the ground with actual tape measures (and of course the photo in hand to insure that the correct locations are being measured), I think we should just forget about the distance numbers. What is clear from the photo, with no need for other information, is that the bird is a robust-bodied woodpecker with a long, narrow neck and a large red crest. This gives us only two species to consider.

ADDED 3/10/2009: Many people online are trying to make this bird into a Red-headed Woodpecker, in spite of the fact that this is a completely untenable ID. Even if accurate distance and size measurements confirm the bird's small size, I'm not sure that is the route to use to explain the mystery bird. The neck on a Red-headed Woodpecker is red, not black. There is no black or white on the neck at all to get stretched and distorted in to a white stripe on black background. The red goes down, uninterrupted, to the base of the nape and on to the upper breast. Those "white straps" on the shoulders are breast feathers protruding from under the folded wing. They will not stretch into a neck stripe no matter how hard you pull. Same with the black on the back; that is the bird's mantle and you can't stretch that into a neck either. If you are in doubt about this, please read "How a bird's neck works". Even if the white stripe is something other than plumage on the mystery bird, the neck is still quite plainly black, not red. So ignore the size and shape issues, stretch a Red-headed's neck until just before it snaps, and you still won't get a black neck. The mystery bird is not a Red-headed Woodpecker.

ADDED 3/12/09: A couple of points on some things that have been suggested online in various places:

If we are looking not at a right side view but at a dorsal or a ventral view, what exactly is the bird perched on? If it is perched on the adjacent tree trunk, we pretty much have to be looking at a right side view of the body. If it is positioned in some other way, it would appear to be floating free in space. In addition, the lightish arc on the upper left of the bird's body is situated just right to be the upper curve of the folded wing for a mostly right-side view, and agrees with the apparent point at which the neck stripe goes under the wing.

If the apparent white shield is just sky shining through, where is the lower half of the bird? The sky would have to be shining through the bird. A transparent Pileated seems even more unlikely than a leucistic one.

Conclusions

My conclusion? Well, that hardly matters. Everyone who sees this image will form their own conclusion regardless of what I might think. I've simply spelled out some of the important features I find in the image, which I hope you gentle readers will find helpful in forming your own conclusions. I will summarize, than in my judgement in order for the bird to be an Ivorybill we have to accept two "unlikelies:" the hidden dorsal stripe and the very existence of the bird in this location. For it to be a Pileated we have to accept one "unlikely" (the white shield; a Pileated with a white shield has still never been documented by photo or specimen) and one "seemingly impossible" (the configuration of the neck stripe). Of course some would rate the existence of the Ivorybill also as a "seemingly impossible" not just an "unlikely," in which case they will find the evidence tied. Conversely, one could conclude that the existence of a white-backed Pileated is equally dubious, and rate that as "seemingly impossible" as well. Which means, once again, it may come down to your own preexisting and personal beliefs about the possibility that the Ivorybill could still exist at all. What I will find most interesting is not the conclusions of the regular disputants; rather, I will be curious to hear the feelings of the great masses of experienced birders who have been following all this much more quietly and with far less rigid opinions than we loudmouths.

Animations and other content copyright 2009 William M. Pulliam; source materials copyright 2007 Steve Sheridan and used with permission.

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