Trail Cam Captures Redux: Beyond (My) Reasonable Doubt, Part 2

The previous post generated a number of responses, mostly positive, but there were a couple of negative remarks, one of which I thought I should address.

One claim was that this new way of examining the imagery (which was misleadingly described as “enhancement”) confuses the issue and makes the images harder to assess. In reality, the processes used in the previous post and in this one are for the most part not “enhancements.” While I have used various image enhancement tools in the past, most of these treatments use unaltered original images to create composites that make it possible to separate figure from ground and parts of the target from artifacts. It’s not a perfect method, but it’s an illuminating one, even with low resolution images. It requires no special forensic expertise. As should become clear from this post, it can also be useful for estimating size.

The images examined in this post were all captured December 7, 2014 on a Reconyx Trail cam that was showing its age. They were previously discussed here, here, and here.  As in the previous post, I’ve used Luminar to create the composites and apply various effects for this deeper dive. As always, views can be had by clicking on the images themselves; mousing over the images will reveal captions in most instances, and I have added versions with arrows to help orient you. I strongly encourage you to examine the images closely.

One initial comment about these images and the ones discussed in the last post: I’m personally convinced beyond a reasonable doubt that two of those images show Ivory-billed Woodpeckers. The images discussed in this post show fewer details, so they may not be quite as compelling. Either way, the captures under discussion are only part of the mosaic, and the subjective conviction that we have found Ivory-billed Woodpeckers in two locations is not solely dependent on them. The audio from last year, for example, is strong evidence in its own right. Go here for a detailed discussion of evidence gathered since 2009

I’ve reposted the original captures in tiled mosaic form below; I’ll follow that with some composites and comparisons among the images. I think the results are helpful if not quite as revelatory as the ones in the last round.  A very prominent American birder tweeted that one of the images below shows a Blue Jay (9.8-11.8″) and characterized the suggestion that it might be an ivorybill as “crazy”. (This is the capture I think is likeliest for ivorybill in this group.) I think his knee-jerk suggestion is absurd, as this approach to reviewing the images should make more apparent.

 

I’ll begin with the raw image I’ve always liked most for ivorybill, as previously discussed in detail and in comparison with Imperial Woodpecker captures. (Note that the version comparing putative IBWO and IMWO has been enhanced.)

IMG_4195

Suspected Ivory-billed Woodpecker

rotatedcomposite

Rotated, resized image of Imperial Woodpecker in flight. The bird is angled downward and slightly away from the camera obscuring the bill and foreshortening the profile. An automated motion blur reduction feature has been applied to the image of the putative ivorybill.

The next image shows the difference between the foregoing frame and one captured approximately 40 minutes later. The bird to the left of the snag is clearly closer to the camera (which was approximately 85′ from the target snag), between it and the snag. The composite strengthens the impression that the suspected ivorybill is behind the tree and the foliage behind it, since at least some leaves appear to be between bird and camera. Frank estimated the foliage as being 15′ more distant.

 

In the earlier discussion, several Pileated Woodpecker captures, including the one below, were used for comparison. These captures were taken from a slightly different position, but that’s irrelevant to the issue of size relative to the reference object, the jug handle-shaped stub.

IMG_2735-1

Pileated Woodpecker on Snag

It may be even more instructive to contrast the capture with the Red-headed Woodpecker, apparently caught as it was preparing to land on the snag. The comparison suggests that the two birds are approximately the same distance from the camera. The possible ivorybill’s body is considerably longer than the Red-headed Woodpecker’s wingspan (14-17″). Thus, between the Pileated Woodpecker (~16-19″, with southern birds typically on the smaller side) and the Red-headed Woodpecker, it can be inferred that the suspected ivorybill is approximately the right size (19-21″), considerably larger than a Red-headed and somewhat larger than a Pileated. I am unable to think of an alternative ID for a bird of similar size and shape, even leaving aside the fact that a white trailing edge seems to be present even in the original, unmodified version of the capture. (The trailing edge becomes more apparent when the image is processed to reduce motion blur.)

 

A different but related method of image processing is helpful for understanding the position of the bird relative to the snag and also suggests that another capture in the series is at least size-appropriate for ivorybill; the tuck and the long, pointed shape of the wings are also intriguing. The first composite shows the unknown bird and the Red-headed Woodpecker. (Note what seems to be a wing, species unknowable, protruding from behind the snag; it appears in the Red-headed frame and no others and had gone unnoticed until now. On looking again, this could also be a squirrel’s tail, albeit unusually positioned.) The second is an overlay of the suspected ivorybill capture and the unknown bird processed using Luminar’s “Color Burn” feature; the two birds appear to be approximately the same size and in the same plane. I’ve added a shot of a Pileated Woodpecker in flight, with wings in a similar position, for comparison.

 

 

 

 

 

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Another capture from the morning of December 7 has always interested us. The underwing pattern and shape are suggestive of ivorybill and reminiscent of one of the Singer Tract photographs. But questions about size have lingered. Comparing this image with two others from the same deployment that show Red-headed Woodpeckers may be helpful, and it has pushed me toward favoring Ivory-billed Woodpecker for this capture as well.

IMG_4399

Either Ivory-billed or Red-headed Woodpecker Depending on Size

 

 

 

 

This capture seems more ambiguous to me, but a few factors are more consistent with Ivory-billed Woodpecker than Red-headed Woodpecker. Both Red-headed Woodpeckers, one captured on the same morning under similar lighting conditions, appear to be closer to the camera than the possible ivorybill. My efforts at measuring wingspan were crude, but the suspected ivorybill seems to have a slightly greater wingspan, despite the upturned angle of the wings and apparent greater distance from the camera. This would tend to exclude Red-headed.

The comparison is also useful insofar as it shows that the wing and body shape of the possible ivorybill are not similar to the Red-headed Woodpeckers captured during this deployment. While Red-headed wing and body shapes can resemble ivorybill at certain angles and under certain lighting conditions, as Bill Pulliam documented years ago, the tail in this image looks too long relative to the body, and the wings look very narrow, at an angle that I don’t think would create an illusion of elongation.

As always, I’m open to correction, and my interpretations are provisional. Intelligent and informed comments are welcome.

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Trail Cam Captures Redux: Beyond (My) Reasonable Doubt

I’m making another departure from my posting schedule for reasons that I hope will be self-evident. This is the strongest statement of my views I’ve made to date; I’m calling it as I see it based on this new way of looking at the photographs.  As always, click on the images for better viewing.

A Louisiana photographer (and new Project Coyote member) who has been following our efforts, reached out to me in response to the recent trail cam capture and alerted me to a feature in Photoshop. This feature makes it possible to stack two images and subtract the identical pixels, leaving the differences between the two images visible in the new composite.

I understand that this is sometimes referred to as subtracting and sometimes as ghosting. Given my limited knowledge and skill set when it comes to image processing, this was a revelation. The method is described between minutes 1 and 2 of this YouTube video. (The rest of the segment pertains to image stacking for landscape photography and is not relevant to this discussion.)

He sent me three examples – the recent capture, the neckbird, and a pair of photographs showing what Frank Wiley had identified as a female Ivory-billed Woodpecker in flight. I didn’t get any new insights from the last of these; the results for the most recent capture were interesting and possibly significant; the neckbird was a revelation, eliminating any lingering misgivings I had about the image and convincing me (at least) beyond a reasonable doubt that it shows an Ivory-billed Woodpecker.

Bear in mind that the images discussed below are among a handful of captures (out of well over a million images obtained since 2009) that we’ve found to be suggestive or better. (At the 20 second interval used on our current cameras, a single month’s 12 hour-a-day deployment will produce over 60,000 images; the Reconyx cams had a 30 second interval, but that’s still over 40,000 per camera per month.)  So it’s not as if we’re finding possible ivorybills everywhere, let alone frequently.

I recently started using a different, ostensibly more user-friendly, image-processing program, Luminar, and I found that it has the same capacity. I tried it on the other oft-discussed trail cam capture with the same revelatory result, although in that case, I did not have access to both unprocessed originals and had to use one cropped image and another that had been cropped and lightly processed for brightness and contrast. I don’t think this impacted the results. I used Luminar to process all the images discussed below.

Immediately below is the original “Neckbird” capture and an enhanced crop, followed by the processed image, showing the difference between this frame and the one before it. Next is a detail, showing the ‘ghost’ outlines of the image that appeared in the original. (Note that a second bird may be present in the form of a bill protruding from the lower cavity in the snag at right, as discussed in this post.)

 

 

 

 

 

 

 

For me, the most startling result is that the bird looks even more serpentine and elongated in this iteration. This is mostly because the lower third of the body (apparently including part of the tail) is better resolved and distinguishable from surrounding objects. What I had thought was a patch of white near the base of the bird, just above the lower diagonal branch, turns out to have been a leaf. I think this longer, leaner profile is inconsistent with Pileated Woodpecker and consistent with Ivory-billed Woodpecker, and not just because of the neck, the feature that was most suggestive to many who viewed the original capture. I’ve seen a lot of Pileateds and have looked at countless images online, and nothing about this better-resolved silhouette suggests Pileated. The remnant clips from the 1935 Ivory-billed Woodpecker film may be illuminating in terms of neck and body shape.

The silhouette in the November 30, 2009 capture, which was the first suggestive image we made public, is not as compelling as the one in the image shown above, but the capture shows three apparent ivorybill field marks – a black crest, white on the lower part of the bird, and a large, light-colored bill. In this case, the processing provides additional information about these apparent field marks. The bird also appears to be larger than a Pileated Woodpecker. The basics of all these issues are addressed in Frank’s original discussion of this capture.

To reiterate, I am not in possession of the original frame that follows the capture. It was probably lost after Frank’s passing, so I used two crops for the first composite, one showing the suspected ivorybill and the other, the subsequent frame. The crop of the empty frame was otherwise unaltered, but the one with the bird had the brightness and contrast adjusted. The output differed slightly between the “difference” version and the “subtraction” version, something I did not observe when working with unprocessed images. The difference, however, appears to be limited to background features and not the bird.

Remember that this capture was obtained from a spot where I’d had a sighting of a large woodpecker with a lot of white on the wings on the 25th . Both Frank and I heard the wingbeats, which were loud and distinctive. This was a rare instance in which a bird appeared to have been brought in by a double knock series. We’d also had an auditory encounter about 300 yards away on the morning of the 24th, while staking out the cavities in the willows shown above.

The first image shown below is the original capture with the red box around the bird. The crops appear as a pair of images. The first shows the bird, and the second is the subsequent frame with the bird absent. Those are followed by the difference and subtraction composites. More discussion after the images.

 

 

 

 

 

As I read this imagery, I think it suggests that the apparent white saddle is part of the bird, not light leaking through or an intervening object; indeed, the intervening branch is revealed in the ghosted images, with the body of the bird still visible behind it. That said, this may be the most ambiguous aspect. The treatment also highlights the presence of the crest and shows it is part of the bird; there is no red in the original; if any red were present, it should be at least faintly visible at this range and under these conditions. This interpretation is based both on the color in the background and on a Pileated captured perhaps six feet farther from the camera during this deployment (in an overexposed image included in Frank’s original analysis).

Most important of all is the fact that both the difference and subtracted versions confirm that the apparent very large bill (which appears to be light-colored in the original picture) is indeed a bill and not some other object. Even allowing for some motion blur, the bill is disproportionately large and therefore inconsistent with Pileated Woodpecker. Indeed, all discernible features in this photograph are consistent with female Ivory-billed Woodpecker and nothing else. I have always believed this picture showed an ivorybill. Based on these composites, I am now firmly convinced that it does.

I also tried creating a composite combining the capture, which was taken in the late afternoon of November 30, 2009, with another frame taken in late morning on the following day. The results are somewhat less distinct but the same elements are still apparent.

 

Finally, I tried this approach with the images discussed in the previous post. The results of this effort were somewhat less satisfactory. I assume because the originals are lower resolution and therefore contain fewer pixels. Lighting conditions may also be a factor.

This capture offers a lot less to work with. The Reconyx jpegs are 2048 x 1536 or 3 megapixels, while the Plotwatchers are 1280 x 720 or less than 1 megapixel.

I was unable to find additional specifications for the Reconyx cams, but the folks at Day 6 Outdoors were kind enough to provide them for the Plotwatcher. Per Day 6, the sensor is .25″ (which is smaller than most cell phone cameras); the focal length is 3.5 mm (which I think translates to the equivalent of an ~20 mm lens on a full frame or 35 mm film camera); and the aperture is f/2.6 (apparently the equivalent of ~f/16).

Nevertheless, I experimented with using both the original captures and versions enlarged using Topaz A.I. Gigapixel. I applied the same process to the squirrel capture from a few weeks earlier, which was taken under better lighting conditions. The relevant images and discussion are below, starting with an enhanced version of the original capture with an arrow pointing to the object of interest. Remember that the silhouette that resembles the head and neck of a woodpecker is background vegetation. The object of interest is the small bit of black and white below it.

 

As mentioned, I’m less confident about interpreting the results for this image, since so much less detail can be gleaned. Unlike the other captures, the subtraction or ghosting does not reveal a clear outline, and aspects of the object which are distinct when moving from frame to frame are obscured in this treatment. Also note the near absence of difference between the preceding and following frames.

In the enhanced iteration, a little more of the outline of the putative IBWO may be visible. I suspect that the reason the white saddle does not appear uniform in this one is due to pixels and that the dark patch below the bright white band is consistent between images because the foreground and background pixels match, not because they’re the same. This explains why the bottom part of the saddle, where the wings meet, is also white. In other words, these are the places where the object was in front of darker pixels. That’s my guess based on shifting back and forth between the relevant frame and the ones before and after. In addition, the white dots above the “saddle” may represent dorsal stripes.

Things change slightly when using imagery from different days. I’m only using the enhanced versions here, but they again strongly suggest that the white saddle is part of the object, not the background. The second frame is the one that follows the squirrel capture discussed below.

 

The squirrel capture may provide some additional insights into the process’s limitations with lower resolution images. The squirrel, which is clearly visible in the original image, shows up as a narrow strip that’s easily missed if you don’t know it’s there. The second version is a composite using images processed through Gigapixel A.I.

 

 

Weather and lighting conditions differed considerably between the two days in question. The camera was pointed in an approximately easterly direction, probably more ENE or NNE; lighting conditions may account for the fact that this image is a little lighter and some small differences are more apparent from this pair of captures. The weather at the nearest station at the time of the squirrel capture was fair with little to no wind; whereas the weather for the putative ivorybill capture, which was taken in the afternoon, was intermittently stormy with winds probably around 10 mph. Under stormy conditions with foliage moving in the wind, there should be more variation between images, not less, so available light seems a likely factor perhaps in combination with number of pixels.

Thus, I’m not sure how much this process adds when it comes to interpreting the most recent capture and how useful it might be with others from Plotwatcher trail cams. (The two older images were taken with a color Reconyx.) But I hope that the cameras are now deployed in such a way that enhancement and differentiating won’t be necessary.

While the approach does not reveal much when it comes to the new image, I think it is dispositive with regard to the old ones. Of course, I make no claims to expertise in forensic image analysis or the technical aspects of image processing, so I am open to being corrected if any aspects of my analysis are flawed.

Like most searchers, I have tended to focus on whether the evidence is sufficient and have seldom thought about what obtaining conclusive documentation might imply. If the two images from the old search area are ivorybills, a number of questions emerge. So let’s assume (or assume arguendo if you are unpersuaded) that these images indeed show Ivory-billed Woodpeckers:

As an initial observation, if I am right about the two captures, I think it becomes overwhelmingly likely that the apparent bill protruding from the cavity in the background of the neckbird image  also belongs to an ivorybill, so it seems probable that least two birds were present in the area in 2009-2010. This is consistent with what six of us heard during an auditory encounter in January 2010. One of Frank’s sightings involved three birds. (He was accompanied by the landowners’ teenaged grandsons at the time.) This sighting suggests that breeding might have taken place in the area.

The habitat in the immediate vicinity of the camera trap deployments is not what has been thought of as having much potential; the quality is even lower than I realized at the time. I knew a lot less about forest ecology and conditions in 2009, and while I certainly recognized the habitat as not “optimal” back then, I think I overestimated and perhaps romanticized the overall quality.

Both captures come from within 50 yards of a bean field. The woods in the immediate vicinity did have a number of large trees, and there are good sized cypresses in the area, but the parcel and the neighboring ones (including the one that was clearcut) are not particularly old. Back then someone indicated they’d been cut in the early 1960s.

The site of the earlier trail cam pic and our November auditory encounter is .6 miles from a large parcel of state land that has some very mature forest and inaccessible areas. (The location of my November sighting and the second trail cam capture is approximately 300 yards farther east, away from the public land.) Several other large parcels of public land are within a few miles of the area, so it’s not exactly a suburban backyard. Nevertheless, it’s a far cry from the Singer Tract or our current search area for that matter.

It seems to me that if one accepts that a pair of ivorybills was present in this location in 2009, there’s no basis for doubting the landowner’s claim that birds had been present and using the area for a decade or so. It also supports the idea that audio obtained there included ivorybill kents and double knocks, which tends to validate audio captured elsewhere – Arkansas, Florida, South Carolina, and our current search area.

How does/would the confirmation of ivorybill survival, especially in such ostensibly low quality habitat, impact the assessment of other reports?

Why is that ivorybills are being reported in so many different places over the last two decades? Is it just more publicity, or is something else going on?

Why aren’t there more reports from the public and from experienced birders?

Why are they so hard to document?  Even if you read the Project Coyote trail cam captures in the most liberal possible way, there are no more than a handful of images that I think of as likely, out of well over 1,000,000.

Where does one look for them, especially if they are using habitat always thought of as unsuitable?

What is suitable habitat?

What kind of population is out there and how has it sustained itself for so long?

I’m sure there are more, and I don’t have good answers for most. I think the technical limitations of trail cams, scarcity, and wariness (even run-of-the-mill or somewhat overdeveloped wariness) are probably adequate to explain many of the documentation issues but perhaps not the relative paucity of sightings.

I hope to return to my planned posting schedule with the post on range in a week or two and the one on evidence a couple of weeks after that; however, I’ve been looking at composites created from the Reconyx images discussed here. I think the results illuminating with respect to size. This post is already long, so rather than include them here, I will likely do a follow-up examining those images before turning to more general ivorybill-related topics.

 


A Tantalizing Trail Cam Capture

Best laid plans . . . I’m pushing back the posts on historic range and evidence but hope to get to them soon.

In going through some of the remaining unexamined images from past trail cam deployments, Geoffrey McMullan came across an intriguing image. He sent me the file for the entire day without indicating where the image was located or what interested him about it. Reviewing cards is challenging; it’s tedious, while demanding focus and attention to very subtle changes. It can be easy to overlook hits of any kind. Nevertheless, this particular frame leapt out at me immediately, even though the object involved is indistinct and is only present in a single frame (more on that later).

I’ll begin by sharing and discussing the image, before and after stills, a time lapse video, and some additional captures comparing other animals with what’s shown in the frame. I’ll follow that with some of the discussion that has taken place among the active searchers in our group and some of the biologists who are advising us. Matt Courtman suggested that everyone on our email list give three reasons they like the image for ivorybill and three counterarguments. Not everyone followed the suggested format, but I’ll draw on those emails as well. I’m hoping this will give you some insights into our process and also give you some additional ways of looking at the image, which I believe to be a picture an Ivory-billed Woodpecker, even as I recognize that it isn’t nearly good enough to stand as proof.

I’ve done my best to present this material in a clear and careful manner. This is not an image that lends itself to immediate, easy interpretation, as some of the discussion reveals. At the same time, a lot can be gleaned from a close, careful look at the raw image, and the preceding and following frames. The various enhancements and comparison captures provide additional context.

A further caveat: I write this blog to maintain a log of our efforts and to share our results with readers on an ongoing basis, in an honest and transparent manner. As with any scientific endeavor, our search is in a constant state of flux. Everything is subject to change and reappraisal based on the evidence. We offer this image with that as background. Most of us believe subjectively that we have found an area that is used by Ivory-billed Woodpeckers, at least periodically. We all recognize that we do not have enough objective “proof” to “convince” third-parties that this is so. The subject image, so far, is just an intriguing part of the mosaic. It’s up to you to decide whether it moves the needle toward “proof” in your mind.

The image was captured on July 12, 2017. The target tree is a hickory that lost its top in a storm in March of that year. And we’ve had a camera aimed at it ever since. This is in area where we’ve found extensive scaling on hickories over the years and where we’ve had a number of auditory encounters. It is within the same contiguous forested area, several miles from the site of the March 2017 recordings. While squirrels are frequently captured on the target stub, there have been few woodpecker hits, and there was no obvious foraging sign on the trunk when I last visited in June.

Perhaps the most informative way to view the image is to step through the time lapse video frame by frame and compare the before, during, and after images. (You may have to download the clip to do this.) This will help clarify what’s object and what’s background. If you’re having trouble downloading the clip (and associated comparison clip), contact me, and I will share the files via Dropbox. I encourage you to click on the individual still frames to see larger, zoomable versions.

Here are two versions the relevant capture, one in its original, unprocessed form and another with a Luminar vividness filter applied, sandwiched between unprocessed captures from 20 seconds before and 20 seconds after. The arrow is pointed at the object of interest.

 

 

 

 

 

 

 

 

 

 

 

 

Here’s the time lapse video clip.

 

 

 

Here is a version of the still, resized using Topaz A.I. Gigapixel, an automated, artificial intelligence-based, image enhancement program. Following that are two enhancements, and a detail therefrom, made using another processor, Let’s Enhance. Both of these programs are automated, so except for selecting enlargement percentage and general processing parameters, I had no influence on the resulting images. Note that the prominent silhouette, which suggests a woodpecker’s head and neck, is blurred, background foliage, not part of the object. Assuming that the object itself is an ivorybill, I think the capture suggests the bird is angled slightly away from the camera, with head and neck inclined to the right.

 

 

 

Edited to add: A significant number of readers have misinterpreted the image, despite my explanation. To reiterate, the somewhat woodpecker head and neck-ish silhouette is background vegetation. The object’s head and neck are not visible. This detail, scaled up as much as possible, should be helpful, despite the loss of resolution.

Detail of Enhanced Detail 7:12:17_output (1)

 

Next are a squirrel and a presumed Red-bellied Woodpecker (9-11″ including head and tail) captured on a different day. They are included for scale. Both are a little lower on the trunk and are therefore closer to the camera. The captures are followed by a 50-frame Quicktime clip showing both the smaller woodpecker (suspected RBWO) and some squirrel activity. The comparison suggests that the object, which appears to be perched in typical woodpecker fashion, is too big to be a Red-headed Woodpecker (8.3-9.8″ including head and tail) and is slightly larger and more substantial than the head and body of an Eastern gray squirrel (9.1-12″). No tail, head, or neck is discernible, so the size of the object is in the appropriate range for an ivorybill body. (Total length is given as 19-21″ with tail at 5.5-6.7″ and bill at 2.3-2.9″) More discussion, including my responses (in italics) to some questions and comments (in bold and italics), is below.

 

 

 

 

An ornithologist wrote:

. . . I have tried every possible way to call that something other than ibwo but I can’t make it into anything else. The general impression of size and shape and even posture / body position relative to the tree is spot on.

And then in response to my explanation about the foliage that had caused some confusion:

I was seeing body only, folded wings white patch.

Early on, I had the following exchange with another biologist and ivorybill researcher:

Interesting. First, as I said before, I am no expert on trail cam photos like these. It looks like a black and white object for sure, with white on the bottom, but to my eye it is not possible to determine what kind of object it is. For sure, a bird would make a lot of sense. And if it is a bird, given the location, and pose on the trunk, a woodpecker would make a lot of sense. I am not sure if I see white at the top of the object as well?

How big is the tree that the object is sitting on, and is that scaling on the other side of the tree or remnants from when a branch that broke off? Have you seen bark scaling in that neighborhood?

I replied:

I’m pretty sure that it’s a bird and therefore a woodpecker. 

I think I see a white saddle and possibly a dorsal stripe. I also think it is too big to be a Red-headed, based on the squirrel and on a smaller woodpecker that’s on the trunk in another frame from another day; I’ll have to find that image.

The tree is a large hickory stub. What looks like scaling is where bark came off when the top fell. It is in an area that has had a good concentration of hickory scaling over the years.

If you have software that enables you to step through it frame by frame, the movie clip can be very informative. Flip Player is an easy one to use.

The response:

Thanks. I just looked at the entire series step by step with Quicktime and it is very intriguing. One question: could some of the white (or all of it) actually be sky in the background? The other frames show sky in the same location. I am not saying that it is, just trying to rule out possibilities.

My answer (another person raised a similar question):

I don’t think so. To my eyes, it’s pretty clear that the white is on an intervening object. I think the white on the object actually covers some of the dark area (as well as the lighter patch) behind it in the preceding and following frames.

And the conclusion:

Good. It is a very intriguing picture.

There was also this exchange with a consulting biologist:

Thanks Mark, well at least I see something here that should be encouraging to all.
Still, I’ve seen reconyx images of what ended up being squirrels that really had me going, where white seemed to be in the “right” places, but then a subsequent image would show a clear squirrel.  Those were black-and-white images and this of course is color, but unfortunately only one image in this series shows something.  
Thanks for sharing as always,

I replied:

If it’s okay with you, I may include a version of the comment in the blog, anonymously of course. 

One quick response, there are lots of captures of squirrels on the stub, but none from that day, based on several runs through the footage. In my experience, it’s extremely rare to see a squirrel in a single frame (20 second intervals) and not in any others. Also, none of the squirrel hits look remotely similar or show black and white coloration. I’ve now viewed several hundred thousand frames from these cameras. 

I can’t prove a negative, but I’d bet my bottom dollar that it’s not a squirrel.

Similarly, and while no one has raised it, I think partially leucistic PIWO can be rejected; I’ve spent a lot of time in the area and have never seen one, and all PIWOs captured on this trail cam and others nearby have been normal.

The rejoinder:

Sure, no problem.  But let me add the following.  

What are the chances of a large woodpecker kind of critter showing up all of sudden in one frame and no sign that it either flew in or left or was in view beyond the one frame 20 seconds or anytime later.  

An alternative could be some other sort of critter ( apparently larger than gray squirrel, perhaps fox squirrel, possibly raccoon) that worked up from the ground up the tree and then went back down out of view of the reconciliation.

As you said can’t be sure this is even a woodpecker or any other bird.

Beyond all that, still “interesting” but how many times…

I had one point of disagreement:

I mostly agree – with one quibble. It’s not unusual for birds to show up in a single frame and no others (the probable RBWO in the other clip, for example); it’s much rarer and (more difficult) for mammals to do so.

My bad for not deploying the camera closer to the target; in my own defense, I’ve only just started to get a handle on how to work with the cams. It was not my department until recently. I was a little concerned about distance with this deployment but not concerned enough . . . some auspicious timing here, since the image turned up while Tommy was servicing the cams.
Going forward, anything larger than a DOWO that turns up on target trees (though not in the background or flying by) should be identifiable.

My correspondent recognized the quibble as a fair point, and it bears repeating that there have been very few woodpecker hits on this tree, probably because it is very recently dead. This exchange also led me to suspect that some of my colleagues were thinking the background foliage was part of the object in question. The discussion ended with this observation:

You are right Mark, I was interpeting the background veg as looking like the neck and head, which really made me wonder why so faded. However, now we have a frame 33 of the Luneau Video situation.

Anyway, thanks for the re-orientation.

Another member of the group also mentioned Luneau, and the similarity is striking, although there’s no accompanying video, and this single capture seems to show more than the Luneau frame.

This exchange with another advisor came soon thereafter, although the initial comments were made based on thinking the foliage artifact was part of the object. My answers came after the clarification, and I’ve deleted the comments that pertain only to the foliage:
Positive impressions –

1) first the obvious, I can’t tell much from the original picture other than it is long and somewhat “thin” relative to more stocky animals. Based on the zoomed in picture, however, it is a live bird; I can see no way it was photo shopped or that it was placed there as a wooden (or otherwise) replicate. I think it is easy to dismiss any attempt at faking it.

Definitely no fakery here 😉

2) The zoomed in image is impressive, it certainly appears to have a white back (which is a slightly different color than the white of the sky next to it) and I see what appears to be two white stripes on the back as well. The comparison of a probable RBWO on the same tree is noteworthy and clearly shows the relative size of the bird in question.

I think the size comparison stands regardless.

Negative concerns –

1) Any of the above positive impressions may be a function of zooming in well beyond the camera’s ability to correctly interpret what’s really there.

Actually, I think that it’s somewhat more compelling unaltered, if you can toggle.

3) The only one frame concern ****** brought up . . . . . . while I don’t think this is a squirrel or mammal of any kind and I’m not at all concerned about this particular series (see below), I am puzzled that the bird in question would not have shown itself on other occasions as well. Are there any pictures of this tree with a PIWO on it? How many pictures (days) do you have images from this camera on this tree? Is the primary foraging area on the other side of the tree? I’m assuming you have several days in not a few weeks worth of pictures on this tree (?)

The camera has been there for over a year, and I’ve gone through countless images. No other suggestive hits. Lots of squirrels. I don’t recall specific PIWO hits on the target tree, although there may have been some, and I’m sure there were at least a few from the deployment. This is one of the targets that has no scaling on it as yet; visits from woodpeckers have been few. As with the RBWO, I suspect birds may be hitting the tree in an exploratory manner at this point and are not staying long.

Just FYI . . . .This is [not far] from where we saw the bird that I ended up thinking was a RHWO and that you weren’t quite so quick to give up on, closer to where I had the long neck and tail silhouette sighting after some ADKs.

An additional note about not concerned about this series and only one frame . . . . .I feel strongly that IBWOs are incredibly wary, much more than we have been assuming them to be. And as any resident bird, it knows its territory very well and that anything “new” or different in that territory could spook it. I hunt as you know, and can vouch that turkeys and waterfowl are often that way . . .one thing out of place from the normal and they leave . . . 

With that said, I wouldn’t be surprised, if this is an extremely wary IBW, that it knew something was not quite the same in the area and stayed on the far side of the tree on purpose  . . .  Even as I type it and re-read it, it sounds a little crazy but since I know about that level of wariness in other species I take it seriously. I know the discussions about wariness and “Tanner’s birds” etc but not sure birds now would act the same way as birds 60 – 80 years ago. If they are that wary, then that also has implications to where the camera is moved. It has to be close enough for a good picture but far hidden well enough to not spook the bird. (If you talk to Tommy or others about new deployment of the camera, my thoughts about how the wariness of this bird is pretty well known and doesn’t have to be anonymous).

I’ve wondered about this myself, and it seems like a pitfall when it comes to putting cameras very close to target trees. With time, however, I suspect birds would become habituated. It’s always a trade-off with these cams, and unfortunately, they have to be placed quite close to the targets.

Thanks for keeping me in the loop Mark – all in all, this has the most “real” field marks and most potential of anything I’ve seen.

I really do think it’s an IBWO . . . it’s at least more cause for optimism and grounds for staying with the trail cam strategy. As I’ve said, I think we’re finally in a position to do it right.

Here’s the response:

Thanks for more clarification Mark – yes I did toggle back and forth, now that I’m not so worried about what I thought was head, neck and bill, the unaltered is more intriguing.

Good to know its been there a year, I agree that birds will get used to it being there over time. The picture has July 17 2017 along the bottom, is that correct or is it July 2018?

I also forgot that this was a tree that you were interested in before any scaling started . . . .that’s pretty exciting and would explain my other concerns about infrequent use and no PIWO use. Pretty exciting in that (if a 2018 picture) the best is yet to come for woodpeckers. Regardless of IBWO, keeping a camera on this tree and having a sequence that shows which woodpeckers use tree, when and how (assuming there are differences based on tightness of bark etc) would be cool from that area.

Frankly, as I was looking at the picture(s), I thought a few times “Damn, I think he got it” . . . . . . Thanks again,

I replied:

The picture is indeed from 2017. But there’s no scaling on it as yet, so it’s worth staying with.

I hope these exchanges help to illustrate some additional challenges related to trail cams, while revealing something about the review process. I think the object in question is an Ivory-billed Woodpecker; so do some of my associates. It’s not proof beyond a reasonable doubt, but it is an encouraging and suggestive piece of evidence.

 


Updated – Emerald Ash Borers and Blonding: A Large Body of Bark Scaling Evidence Tends to Rule Out Pileated Woodpecker as The Source of Scaling on Hickories

A couple of initial housekeeping notes: I still plan to do a second, more conceptual post on ivorybill evidence, one on historic range, and possibly another on non-IBWO trail cam imagery. Look for those over the course of the summer. I thought this subject should take precedence and have changed plans accordingly. The photographs (other than my own), which I’m including in the largest possible sizes, are courtesy of bugwood.org (under a Creative Commons License) and Patowmack the trickster.

Thanks to John Kearvell for inspiring me to pursue this subject.

Summary

The emerald ash borer or EAB (Agrilus planipennis) is an invasive Buprestid beetle. The first known North American outbreak was near Detroit, Michigan in 2002. Since that time, the species has spread to 33 states and three Canadian provinces.

Bark scaling, especially by Pileated Woodpeckers (Dryocopus pileatus), is one reliable indicator of EAB infestation, and Pileated Woodpecker populations appear to increase as a result of outbreaks. Thus, there is now a large body of data on bark scaling that was not previously available for comparison with suspected Ivory-billed Woodpecker (Campephilus principalis) work.

All of the numerous examples of white or green ash (Fraxinus americana or pennsylvanica) scaling by Pileated Woodpeckers (and presumably smaller woodpecker species as well) found online show “blonding” or removal of bark in layers. This may be due to anatomical limitations that preclude Pileated Woodpeckers from removing thick, tight bark in large pieces. Suspected Ivory-billed Woodpecker work on hickories – which have harder, tougher, tighter bark than ash – shows no trace of blonding or gradual removal. I think this excludes Pileated Woodpecker as the source of the hickory scaling.

Introduction: The Emerald Ash Borer

EABs are believed to have arrived in North America in packing materials. The first outbreak began near Detroit in 2002, and the species has spread rapidly since then, decimating native ashes wherever it goes. All indications are that this invasive insect will have an impact akin to that of Dutch elm disease or chestnut blight, concerted quarantine efforts notwithstanding. Because EABs were a recent arrival and had not been well-studied during the first decade of the 2000s, their relevance to the issue of bark scaling does not appear to have been recognized by the formal searches that were conducted during that period.

While the invasion’s impact has already been devastating, EAB larvae are attractive to woodpeckers, especially Pileated Woodpeckers (Koenig and Liebhold, 2017), and bark scaling is one of the most obvious symptoms of infestation. (This attractiveness may have future implications for any surviving ivorybills as the EAB expands its range.)

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Table from “A decade of emerald ash borer effects on regional woodpecker and nuthatch populations”, Koenig, W.D. & Liebhold, A.M. Biol Invasions (2017) 19: 2029. https://doi.org/10.1007/s10530-017-1411-7

Unlike many bole dwelling Cerambycidae, such as Hesperandra politawhich spend the bulk of their lifecycle in the heartwood and do minimal damage to the cambium, EAB larvae live, feed, and pupate just beneath the bark, eventually destroying the cambium. This causes the bark to fracture and sometimes to slough off by itself. In the very dramatic example shown below, I suspect that woodpeckers were involved in most, if not all, of the bark removal but only reached the sapwood well after the bark had started to loosen, fracture, and perhaps fall off on its own. Nevertheless, there are still signs of layered removal on the edges of the scaled/sloughed area.

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EAB Larvae. Photo by Kenneth R. Law, USDA APHIS PPQ, Bugwood.org

 

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Tunnels and bark fracturing caused by EAB infestation. Photo by Joseph OBrien, USDA Forest Service, Bugwood.org

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Entire cambium destroyed by feeding. Photo by Daniel Herms, The Ohio State University, Bugwood.org

Blonding

When I started researching this subject, I was unaware that the term blonding had been applied to woodpecker work in pursuit of EABs, but it has become a widely-used (and apt) descriptive. It refers to the appearance of ash trees or parts thereof, after woodpeckers have started removing the outer bark in pursuit of EAB larvae and pupae. The process of reaching the sapwood appears to be a slow one, and after examining hundreds of images showing of bark scaling on ash trees, I have been unable to find a single example that was devoid of blonding, even when very extensive work was involved.

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Art Wagner, USDA – APHIS, Bugwood.org Damage resulting from woodpeckers searching for a meal on an infested tree

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Kenneth R. Law, USDA APHIS PPQ, Bugwood.org Heavily infested Ash tree with Emerald Ash Borer and woodpecker activity in evidence. Some galleries exposed.

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Kenneth R. Law, USDA APHIS PPQ, Bugwood.org

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Steven Katovich, USDA Forest Service, Bugwood.org Outer bark removed by woodpecker activity

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Steven Katovich, USDA Forest Service, Bugwood.org

 

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Dramatic example of presumed Pileated Woodpecker foraging in pursuit of emerald ash borers. Note remaining traces of blonding on the edges and blonding on trees in the background. Credit: Patowmack the Trickster https://patowmacktrickster.com

Patowmack the Trickster’s photo is the most extensive example of apparent Pileated Woodpecker scaling on an EAB infested tree that I’ve been able to find. The tree appears to be fairly long dead – based on the extent of the superficial excavation (tunnels are no longer distinct), the apparent fracture in the trunk at the center of the frame, and on the apparent separation of the bark from the sapwood that’s most distinct on the lower right edge of the scaled surface. While the extent of this work is impressive, I’d suspect PIWO even in potential ivorybill habitat – based on the appearance of the surface, the state of decay and seeming looseness of the bark, and the blonding, which is most evident at the top and at the lower left.

While smaller woodpeckers are responsible for some ash blonding, Pileated Woodpeckers are likely the primary source, especially when the work is as extensive as in the examples shown above. Images of Pileated Woodpeckers on blonded surfaces are considerably easier to find than ones involving other species. This brief video catches a PIWO in the act, on an extensively blonded tree, and points to the difficulty PIWOs face when scaling tight, thick bark.

Blonding on Other Tree Species

I have found blonding or its equivalent on a number of other tree species, so it is not exclusively related to any characteristics of ash bark. Rather, I think it is a function of Pileated Woodpecker anatomy. I have seen this on limbs, including sweet gum (Liquidambar styraciflua) limbs, in our search area and have described it as a “layered” appearance.

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Known Pileated Woodpecker scaling on a medium-sized sweet gum limb with evidence of layered bark removal or blonding.

It may be possible for Pileated Woodpeckers to remove tight bark from small to medium branches without leaving traces of blonding, especially if the bark is weakened or it comes from a species (like sweet gum) that is relatively soft and thin. Removing thick bark from mature boles is something else again, and I suspect that even when bark has loosened considerably, traces of blonding will often be visible when the work is done by Pileated Woodpeckers.

I have found one extreme example of suspected, extensive PIWO blonding on a bole in Louisiana. I think the tree involved is a sweet gum, but if it is an ash, it would be from a location well outside the range of the EAB today, let alone in 2011 when the tree was found. While blonding is easily visible on the trunk, it can also be recognized by examining bark chips.

 

 

 

I have seen the equivalent of blonding on loblolly pines (Pinus taeda) in the southeast and on softwoods in Westchester County, New York. The bark of most conifers is weaker and less tightly adhering than that of most hardwoods, and it typically becomes easy to scale far more rapidly. This is why I long since abandoned the idea that softwood scaling  might be suggestive of ivorybill, unless it involves extensive work on multiple large trees.

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Loblolly Pine with blonding, South Carolina 2011

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Blonding on dead softwood, Westchester County, NY, 2011

I have also found it on live and dead hardwoods in Westchester County, NY. The first pair of images below, which I’ve posted previously, shows fresh, known Pileated Woodpecker work on a Norway maple (Acer platanoides) in my yard. (I saw the bird.) The second pair is from a local park. The snag, which I believe is a large sassafras (Sassafras albidum), appeared to be fairly long dead.

 

 

 

 

 

 

 

Ash Bark v. Hickory Bark

Ash bark resembles that of bitternut and pignut hickories (Carya cordifromis and Carya glabra), so much so that an arborist mistook the pignut that grows outside my office window for an ash and advised me to monitor it for EABs. Testing bark hardness with a fingernail is one way to avoid confusion. Ash bark feels corky, whereas hickory bark is extremely hard. Last year, I wrote an in-depth post on the characteristics of hickory bark and the reasons it is exceptionally difficult to remove. I won’t recapitulate it here, except to say that hickory bark is considerably harder and stronger than that of virtually any other genus. It is also tighter when trees are dormant or dead, as these reposted tables suggest.

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woodchart

The values shown are for shagbark hickory (Carya ovata), which is slightly stronger, tougher and tighter than bitternut or pignut. While white and green ash bark is considerably stronger and tougher than sweet gum and white ash bark is harder to remove from dead trees, neither species comes close to hickory in any category, except bark tightness when sap is flowing.

I suspect that the extreme strength and toughness of bitternut and pignut hickory bark renders it impervious to blonding. Certain pignuts may be a partial exception, as the outermost bark layer on that species is sometimes slightly subject to flaking. I removed the outer layer of bark from the pignut hickory mentioned above to illustrate; the inner layer is very hard and tight.

 

 

Our observations thus far suggest that Pileated Woodpeckers can excavate through hickory bark, leaving behind small pieces, and can remove narrow strips of hickory bark from already scaled areas.

 

We have found nothing to indicate that Pileateds can go straight from outer bark to sapwood and remove the hand-sized chunks we’ve found under the scaled hickories in the search area.

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Detail of the hickory shown on the home page. Note the absence of blonding on the edges. Also note possible superficial bill marks on the lower right, a detail I had missed, and the targeted digging into the exit tunnels.

Conclusion

All of this strongly supports the hypothesis that Pileated Woodpeckers are incapable of scaling hickories in the manner that I believe to be characteristic of Ivory-billed Woodpecker. I’d further argue that the absence of blonding on boles of any hardwood species may be suggestive of ivorybill, provided the bark is thick (over ~.5″) and tight. This is not to suggest that ivorybill work never shows traces of blonding. Though the image quality is poor, Tanner’s Plate 8 may show it.

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Something similar to blonding is visible in examples of scaling by other Campephilus species. Thus, an absence of blonding on scaled hickory boles may be a basis for rejecting Pileated altogether and may be suggestive of ivorybill when other tree species are involved.

Update

On a recent visit to a park in Orange County, New York, I found many EAB infested, blonded ash trees. I only had my iPhone with me, but I took some close ups and one shot of the chips on the ground. I also collected some chips and photographed them at home. One of these chips was particularly interesting; while it include some of the outer bark, most of it was from an intermediate layer, further illustrating how the bark is flaked off and that multiple events of stripping are involved before the cambium is exposed.


Evidence Part 1: Project Coyote 2009-2018

Summary

Evidence collected by Project Coyote in two parts of Louisiana from 2009-2018 should, on its own, suffice to justify maintaining the Ivory-billed Woodpecker’s current listing as an extant, endangered species in the United States. Others may differ, but I think the totality of the evidence does even more, making a compelling case that the species persists in more than one Louisiana location.

Introduction

This will be a two part post. The initial impetus for writing it was a conversation I had with Erik Hendrickson about how the scientific, birding, and legal approaches to evidence seem to differ. That will be the main focus of Part 2. As for Part 1, after talking to Erik, I realized that I’d never done a single post aggregating the evidence we’ve obtained over the years, so when it was announced that the U.S. Fish and Wildlife Service would be conducting a status review for the Ivory-billed Woodpecker, the need for writing this up became more urgent. That’s the primary focus of Part 1, but some of what I’m planning for Part 2 will be foreshadowed in this lengthy treatment.

There is a strong tendency to privilege visual evidence over other forms – audio and circumstantial. I’m inclined to think that our audio evidence is the most compelling material overall; as regular readers know, I also think circumstantial evidence, feeding sign in particular, is very important. But the structure of this post will track conventional attitudes, starting with visual material followed by a discussion of sound recordings and auditory encounters, and concluding with more circumstantial forms of evidence.

Locations

Project Coyote has been focused on two areas in Central and East-central Louisiana. I found what I call the “old” search area after reading a newspaper account of a local landowner’s efforts to get his reports taken seriously. This is the landowner who sketched corrections to the Louisiana Hunting Guide’s ivorybill illustrations and who showed Frank Wiley (my late collaborator) bark scaling when he visited the area.

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To be clear about what he was trying to show in the corrections: the gentleman died before I had a chance to meet him, but as Frank told me after his August 2009 interview, all of the corrections are in red ink, so the intent was not to put a male crest on a female bird; it was to show the female’s crest as more erect and recurved than the drawing and indicate that the male’s crest also is more erect and prominent (less Pileated-like) than the game guide representation. Also note the drawings at top right, in which he compared IBWO and PIWO wings, implying that the wings in the game guide image are a little too rounded.

What’s most salient about these observations is not whether they are perfectly accurate, although they do seem to reflect some little-known nuances, it’s that the landowner had enough claimed observations of male and female ivorybills to recognize subtle differences and to distinguish them from Pileateds. In addition, he was offended by the treatment he received when he tried to alert the authorities. I have personal knowledge about this last aspect based on conversations with family members who wanted to see him vindicated.

He was certainly convincing enough for Frank to start visiting the property on a weekly basis during the summer of 2009. Thus, Project Coyote was born.

The landowner’s reports go back to the 1990s. (The linked post includes audio from 2009). There are several medium to large state WMAs and National Wildlife Refuges in fairly close proximity to the site. We heard additional claims from residents of the area while we were focused there.

Putative ivorybill activity on the property seems to have diminished or ended altogether after an adjoining parcel was logged in late fall 2010. As a result, we gradually shifted our attention to the new search area.

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The old search area received minimal attention during the post-Arkansas period; some peripheral Ivory-billed Woodpecker-related research was conducted in the general vicinity, but there was no formal, funded search effort. Nor was it visited by Cornell’s Mobile Search Team, although Martjan Lammertink did spend several days on site, after the logging.

Similarly, our “new” search area was entirely off the radar. It doesn’t show up on anyone’s list of promising locations, notwithstanding the fact that it is in one of the most sparsely populated, heavily forested parts of the state. There’s also a long history of local reports. Most of the claims seem to have been fairly recent, but some go back to the late 1990s.

And these are only the claims I know about . . .

Eyewitness Evidence

For reasons that I hope will become clear, I have not kept track of all our possible sightings since 2009 and have not always mentioned them in blog posts. Nevertheless, I’ll begin with sightings. Over the years, Frank had more possibles and reported having better views than anyone else. I’m probably second, with approximately six since 2009, but unfortunately no good looks. Steve Pagans has had several possibles; a few visitors have also made claims.

While this is largely a subject for the next post, it’s well-known that eyewitness testimony is unreliable, at least when the source is an untrained observer. Nevertheless, eyewitness testimony is central to many a criminal trial, and it has a strong impact on jurors. There seems to be a parallel with respect to the ivorybill. Accounts of possible sightings tend to attract more interest than many more substantive and important posts.

Thus my Sunset Sighting post, which is not quite two months old, has had approximately 800 pages views, but my March 18, 2017 post entitled, Numerous Kent-like Calls Recorded on March 11 and 15, 2017 received a total of 744 views last year. Similarly, the post on Joseph Saucier’s October 2017 sighting and our follow-up visit to that location, Change of Pace Change of Place, posted in late November, received 804 page views, the second highest total for the year, (well behind the announcement of Frank’s passing).

According to a survey conducted in the aftermath of the Arkansas controversy, “[R]espondents were most confident in the sightings, less confident in the Luneau video and recordings of double-knocks and kent calls, and least confident in the FishCrow video.” The discrepancy was strongest for the “Definitely of IBWO” category, where 22 people listed sightings as conclusive, compared to 10 for the Luneau video, 9 for kent calls, 8 for double knocks, and 4 for the first Fishcrow video. (PDF) The Great Ivory-billed Woodpecker Debate: Perceptions of the Evidence. Available from: https://www.researchgate.net/publication/259337980_The_Great_Ivory-billed_Woodpecker_Debate_Perceptions_of_the_Evidence[accessed Jun 28 2018].

So sightings have an almost irresistible appeal; in some cases, there’s good reason to credit them, but it is very difficult to separate the wheat from the chaff, to determine what’s trustworthy and what isn’t. And there are many kinds of chaff – wishful thinking, self-delusion, ignorance, mistake, and deception to name the most obvious.

I’ve retrospectively rejected a couple of my possible sightings (and almost did so with the recent “Wooden Wings” incident), partly because I’m disposed to look for reasons to doubt myself and partly because I realized that I was in some way primed in a couple of those instances; for example, in one case, I’d been looking at specimens the day before.   In the absence of a good look, I think it’s better to err on the side of self-skepticism.

When it comes to claims from others, it’s impossible to know with certainty what someone else saw, even when reports are accompanied by detailed sketches and field notes, as is the case with several of Frank’s sightings. I was with him for one, on April 3, 2015, when he made notes (available at the link) and a sketch (at my urging). I have no doubt that he was convinced he saw an ivorybill, as he was visibly shaken immediately afterwards and was very slow to regain his composure.

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But I really like corroboration, and to the best of my recollection, Frank and I had two possible two-person sightings in all our time together – the first was in the old search area, the day after an auditory encounter and a week before a suggestive trail cam capture was obtained, effectively from the same spot. I consider this my strongest possible sighting.

The second was much weaker, a flyover with two birds seen in silhouette within 15-20 minutes of an ADK series. (Three of my possible sightings, two of which Frank also saw, have been associated with ADKs.) We did not think much of this possible at the time but could not explain it away entirely. I should add that Frank had several other two or more person sightings, but I was not present for those.

With regard to the local reports, I’m always mindful of the possibility that I’m being played, especially as an obvious northerner in rural Louisiana, but I don’t think that has ever happened. It’s still necessary to listen closely and ask the right questions. Pileated, Red-headed, and even Red-bellied Woodpeckers can be confusing for non-birders. I’m more likely to credit accounts from people who make it clear they know Pileateds and know the difference (like the landowner in the old search area) or from people who say they thought the ‘ones with the white backs are the males’ and the ‘ones with the black backs are the females’. I’ve heard this only a couple of times. But I like it best when we get ivorybill claims from different, unconnected people referencing the same location; this has happened in the vicinity of the current search area.

To conclude, members of our group have had multiple sightings of varying quality, in two different Louisiana locations since 2009. In addition, there have been multiple claims from locals in both areas.

One final note, relevant to the USFWS review: I am aware of a number of additional post-2009 claims from Louisiana (and a few from other states). In a couple of cases, Frank interviewed the people involved and found them to be credible. A cellphone video was obtained in one instance; the observers’ excitement over apparently seeing a pair of ivorybills is evident, but the quality of the video is extremely poor. In the other case, two people saw the bird and one provided a highly detailed description and sketch. There’s also Joseph Saucier’s report from last fall; our follow-up suggested that much of the habitat in this large expanse of forest was likely suitable, and Matt Courtman, who is an excellent birder, heard what he thought was a very good double knock on one of his follow-up visits.

Photographic Evidence

I recently posted a couple of Frank’s 2009 sightings and accompanying photographs that hadn’t been made public previously. These are the only photographs associated with possible sightings that we have obtained. Full details are available at the link; rather than recapitulate them here, I’ll focus on trail cam photos, including several that have been discussed previously plus a few intriguing ones from the old search area that have not been posted previously.

These are the images I think are most strongly suggestive of Ivory-billed Woodpecker and for which I am unaware of a strong counterargument.

The first two have been discussed repeatedly at length in a number of other posts. Both are from the old search area; the first was taken in August 2009 and the second, which appears to show a female Ivory-billed Woodpecker, was taken in late November, a week after the sighting discussed in the previous section.

To reiterate a couple of points about the August 2009 image: in the original photograph, there appears to be some red in the crest (though it’s not positioned right for either PIWO or IBWO). Careful review and image enhancement made it clear to me that the red is an artifact and the crest is black. In addition, as shown in the enhanced detail, there appears to be a large, light-colored bill protruding from a cavity in the background. This apparent bill is absent from captures obtained on other days. It changes position in the two frames where it is visible, suggesting it is attached to something within the cavity. (Unfortunately, the other frames from that morning have long since been lost.)

The image of a bird in flight, from the new search area, is more problematic, as it is not demonstrably a woodpecker. The still above includes an inserted Imperial Woodpecker for comparison, with motion blur reduction applied to the bird captured by the trail cam. One prominent birder stated that it is a Blue Jay, but as discussed in the original post, the bird is behind the snag and appears to be as large as or larger than a Pileated Woodpecker captured on the trunk.

Although we’ve determined that one of the initially intriguing images from that deployment shows a Red-headed Woodpecker, a few others remain interesting.

There’s an additional image from the spring of 2010 (old search area) that has always intrigued me, though I never had a chance to examine the original. I think it shows a large woodpecker, with a black crest, high on a honey locust. If it were a Pileated, male or female, I’d expect some red to be visible in the crest, even under these conditions.

Finally, there are a couple of additional trail cam captures from the old search area that I have not posted previously. By now, the original sequences are lost, and I’ve long since forgotten any details or discussion we might have had when Frank sent me the images. While they are far from conclusive, I think they are interesting enough to post in this context. At minimum, they further illustrate the challenges associated with obtaining definitive trail cam imagery.

Audio Evidence

Note: If you listen to the recordings below with headphones (recommended) be aware that some have loud sounds, clarinet toots and ADKs, in the foreground. This applies to the clip from March 2013 that I recorded and to many of Matt and Phil’s recordings from March 2017.

Possible auditory encounters far outnumber possible sightings, and over the years we have made numerous recordings of putative kents and double knocks (more than once in combination, which should add to their evidentiary value). Some visitors have been rewarded by hearing something within a day or two of arriving, and this has been true in both search areas, although others have been less fortunate, and I heard nothing suggestive during the most recent field season (though Matt Courtman recorded three possible calls in April of this year).

I will not be including all the audio evidence we’ve obtained, just some of the material I think is most significant. Some of the putative kent calls that have been recorded over the years may be Blue Jays; it has been suggested that Matt’s calls from this spring are too low pitched for ivorybill and might be from a heron, though I think they come from the same source. Regardless, many of the calls are simply inconsistent with any known bird species, are fairly close to the Singer Tract recordings harmonically, and are perfectly consistent with written descriptions of Ivory-billed Woodpecker sounds.

One of the most dramatic encounters involving both apparent kents and double knocks was from the old search area. It seemed to have been triggered by banging from the tin roof of an old deer stand. Six people were present, and much of the incident was recorded. There were apparently two birds involved. More details are in this post, and here is Frank’s 58 minute recording:

Extracts from the encounter and other material recorded in person and on remote units in the old search area and environs, as well as sonograms, can be found here, via the Wayback Machine. Some of the Wayback Machine links are not functioning, and the material posted there includes a couple of double knocks; here are several of the recorded kent-like calls:

Note that the fundamental frequencies on many, but not all, of these calls are in the 900-925 hz range, higher than the Singer Tract recordings and possibly consistent with Blue Jay. But in the second clip above, the fundamentals of both the lower calls at the beginning and the higher calls at the end appear to be a little over 800 hz., and during the extended encounter mentioned above, the calls went on for a prolonged period without the source revealing itself as a Blue Jay, which would be typical if the animal were indeed a jay.

The same applies to calls I heard and recorded in the new search area on the morning and afternoon of March 2, 2013. The morning calls went on for ~20 minutes. I did not think they were Blue Jays in the field.

We have recorded apparent double knocks in apparent reaction to ADKs and to Barred Owl calls and sometimes in contexts where the trigger is unclear, as in this example from an October 2015 post written by Frank:

“Bob and I continued upstream for another half mile, located a nice spot with a good view, and I performed an ADK series, followed about ten minutes later by a series of electronic playbacks of Singer Tract ivorybill calls. Shortly thereafter, Bob heard a double rap drum, that was captured on my digital recorder. I personally don’t believe that the drum was a direct response to my ADKs as there was at least a fifteen minute interval after the last of the ADK/playback series.

The double rap is not “perfect” in that the “intra-knock interval” is about .05 seconds longer than the “ideal” – based on averages of the intervals of other Campephilus drums – but it sounds very good.”

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The 15 minute interval between ADK/playback and apparent response is similar to the lag time that has been observed in other Campephilus woodpeckers responding to ADKs; it may be worth distinguishing between a slower ‘response’ and a more immediate ‘reaction’ in this context. (M. Lammertink, pers. comm.)

In my view, the audio recorded by Phil Vanbergen and Matt Courtman in March 2017 is compelling, perhaps the most compelling evidence we’ve obtained. On the morning of March 15, they recorded over 200 calls, along with a number of possible double knocks, over an approximately three hour period. The calls have lower fundamental frequencies than many of those in earlier recordings; these frequencies are considerably lower than any kent-like Blue Jay calls I’ve been able to locate online. Other suggestions have included, Red-breasted Nuthatch (too high) and Wild Turkey (no typical Turkey vocalizations were recorded that morning).

Overall, the calls appear to be inconsistent with any other known species of bird, mammal, or amphibian. Their association with Campephilus-like double knocks strengthens the argument for Ivory-billed Woodpecker as the source. As far as I know, the sheer number of recorded calls is unprecedented for a single incident in the post-Singer Tract era.

I was lucky enough to hear a couple of the calls on March 11, the day Phil first captured them, along with a couple more and some knocks at the same location on the following day. I’ve blogged about these recordings at length in multiple posts; I won’t repeat all that material here, but the discussions are worth reading. I will repost some of  the original recordings and enhanced versions.

Here is the first recording Phil made, one clip with the calls isolated and one with our talk and reactions. It may be difficult to hear the calls without headphones.

Here are some brief extracts from Phil’s March 15 recordings:

Here are some from Matt’s:

In the interest of brevity, I encourage readers to visit this post for in depth analysis, various extracts, and amplified versions that highlight the calls and some of the knocks. As always, it helps to listen through headphones.

Indirect Evidence: Bark Scaling, Bark Chips, and Cavities

I’ve discussed my bark scaling hypothesis – that a certain type or types of scaling may be diagnostic for Ivory-billed Woodpecker – multiple times over the years. As explored in a couple of recent posts, we are in the process of testing it. I won’t recapitulate the hypothesis here except to say that I remain convinced that neither Pileated Woodpeckers nor squirrels are physically capable of removing hickory bark in the manner we’ve found in the new search area. There may be other diagnostic characteristics, but my main focus is now on the hickories, since the work on that species is the most extreme outlier. Below are some dramatic examples of bark scaling (plus one image of interesting feeding sign on a sweet gum sapling that had been stripped of bark) on hickories, oaks, and sweet gums from both search areas.

For Tanner, bark scaling was one of the strongest indicators of ivorybill presence, even though he accepted some reports from trusted sources in areas where he found no scaling. The absence of scaling (along with poor habitat “quality”) was one of his main reasons for dismissing reports during his 1930s survey and rejecting the ones from the Big Thicket in the 1960s. He also doubted reports from the Chipola and Apalachicola area in 1950 based on finding no cavities or scaling during a 4 day visit. He concluded his notes on the trip by stating:

Conclusion: No I-b now in Chipola R. and neighboring Apalach R. swamps. Many of Kelso’s reports are mistaken, – not deliberately false, but due to ignorance and wishful thinking. There appear to be contradictions in some of his stories. I could not get any clear statement of what Ivory-bills sound like from him. He said that the local name of I-b was “Saddleback”, – which appears good but in many ways odd. Also “Van Dyke”! There certainly is no fresh sign in any area we visited indicating that the birds are present. The only possibility is that of scaling on pine; this may be solved by watching Pileateds in the pine woods.

(F. Bryntesson, pers. comm.)

While I think it’s possible, indeed likely, that some of the work Tanner ascribed to ivorybills was done by Pileated Woodpeckers and squirrels, there’s no question that an abundance of bark scaling is relevant in assessing possible ivorybill presence in a given area.

Based on visits, some lasting a week or more, to suspected ivorybill haunts in South Carolina, Florida, and Louisiana and on information provided by other searchers and people who have spent years in southeastern forests, I feel safe in saying that the quantity and quality of bark scaling found in both search areas is unusual. We also found an abundance of scaling in the area where Mr. Saucier had his sighting last year, something that I think lends added credibility to his report.

In the past, many in the searcher community speculated that lateral groves or bill marks in the cambium or sapwood might be suggestive, but this view has fallen out of favor; much of what was thought to be “scaling” in these instances was in fact shallow excavation with associated bark removal. We found one example of superficial lateral marks in 2013 that continues to intrigue me, although the snag in question is a young sweet gum that could easily have been stripped by a squirrel or Pileated Woodpecker.

IMG_0144

The edges of the scaled area may tell more of a story, especially in conjunction with any bark chips found on the ground. On the trees shown above, damage to the still-adhering bark suggests that lateral blows were integral to the scaling. This would be expected if the source were a Campephilus woodpecker.

An abundance of large, hard, thick bark chips (or chunks) around the base of a tree is also a likely indicator. Pileated Woodpeckers and squirrels seem to remove bark in smaller pieces and in strips. Additionally, when squirrels are involved and the bark has  been recently removed, it’s likely that there will be a lot of smaller debris in the mix, since squirrels have to gnaw their way through the bark. Some of the chips we found in the old search area seem to have bill marks consistent with Ivory-billed Woodpecker.

The bills of specimens, at least, seem to fit perfectly into indentations in the chips, but Pileated Woodpecker bills seem to be too small. The larger chips shown below are suspected Ivory-billed Woodpecker from a variety of species – oak, hickory, sweet gum, sugarberry, and honey locust. The specimen shots are with a honey locust chip from the old search area. The first few images show squirrel and Pileated woodpecker leavings for comparison.

Cavities are vexing. I’ve become convinced that there’s no bright line for distinguishing Pileated from Ivory-billed Woodpecker, notwithstanding the dimensions Cornell gave for “large” PIWO (3.5″ x 3.7″) versus “small” IBWO (4.0″ x 5.0″). The small ivorybill sample was limited to nest holes, and I’ve certainly seen plenty of oddly shaped and large holes being used by Pileated Woodpeckers. Thus, while I keep my eyes open for cavities, I don’t think there’s a reliable way to determine which species is responsible for creating or using large, irregularly shaped cavities, although extensive bark scaling on the tree may be indicator.

It has been a challenge to find cavities of any kind in our current search area, probably due in part to the high canopy. We did find a cluster of interesting cavities in what I call the northern sector in the 2014-2015 season. This cluster was in the vicinity where we’ve found an abundance of scaling over the years and where Phil and Matt made the recordings last year. Below are some of the most interesting cavities we’ve found in the two search areas. Cavities were much easier to find when we followed up on the Saucier sighting, but I’ve omitted those from this document.

In conclusion, there is an abundance of evidence suggesting that Ivory-billed Woodpeckers persist in Louisiana. It is self-evident that none of this evidence rises to the level of proof required for establishing beyond all doubt that the species has survived, but I think the case for persistence is a compelling one, without regard to evidence obtained in other areas since 2005.

Stay tuned for a more theoretical discussion of evidence, proof, and professional approaches thereto.

Thanks to Wylie Barrow, Fredrik Bryntesson, Patricia Johnson, Tommy Michot, Steve Pagans, and Phil Vanbergen for their input. Some photos by Steve Pagans and Erik Hendrickson.


Brief Update: Some Thoughts, Future Posts, and Some Imagery Just for Fun

While I have not been keeping close track of numbers, I’m going to give some guesstimates on trail cam results. Our current settings (~12 hours daily at 20 second intervals) result in ~2000 captures per day with cards filling and beginning to overwrite at somewhere between 80-90 days. PlotWatcher’s proprietary software makes the process a lot easier than it was with the old Reconyx images, which had to be stepped through manually. This is the first time I’ve really immersed myself in reviewing imagery, and even with the ability to review the images in a video format, it’s a tedious process involving a lot of stops and starts.

I’d estimate that I’ve reviewed about 500,000 images over the past 8 weeks, and I’m struck by the relatively small number of hits, especially avian ones. Squirrels make up a significant percentage, probably more than half, the total captures, and I suspect that Northern Cardinals are second. Other common species show up infrequently. I don’t recall seeing any identifiable Blue Jays (although there may be one among the images below). Nor were any Wild Turkeys captured (including on a camera that was mis-aimed, with the target tree at the right edge of the frame and a large open area to the left as shown in some of the captures below).

Woodpecker captures have been extremely rare, except on the targeted hickory discussed post before last, that was already extensively scaled. Among the rest of the images I’ve reviewed thus far, I’ve seen three identifiable Pileated Woodpeckers – one on a target tree (below) and the other two on an adjacent tree that had one pre-existing PIWO foraging pit in the frame – and as best as I can recall, a couple of identifiable Red-bellied Woodpeckers and a Hairy (captures not saved/posted).

PIWO-Plotwatcher-2:28:18

I suspect it would be fairly easy to obtain Pileated imagery in quantity by targeting trees with obvious PIWO foraging sign, but otherwise, it seems even this abundant species is hard to capture in a camera trap. This should help illustrate another reason I don’t think the so-called failure to obtain conclusive ivorybill imagery using trail cams is very meaningful.

Assuming the ivorybill persists, it is a very rare species with incompletely understood behavior, and no one alive today, myself included, knows exactly what makes a good target tree. The best anyone can do is make educated guesses and hope to get lucky, against extremely long odds.

Now some housekeeping: the next couple of posts will be about evidence. I’ve never assembled all of Project Coyote’s evidence in a single post and discussed it as I plan to in the next post, which I expect to take live sometime next week. Look for a more theoretical piece on evidence to follow that. Both of those posts will be password protected for review, though I will try and make them public as soon as possible. After that (probably in August), I’m planning a postscript to the habitat and historic range series.

I won’t be doing regular updates on the trail cam imagery unless there’s something significant to report or I have insights similar to those expressed here.

And now some imagery. It should be illustrative of some of the challenges. See what you can find, including in the featured image . . .

 

 

 

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Recent Trail Camera Results: Part 1 and Trip Summary, June 6 – 11, 2018

Summary/Bottom Line Up Front

5 of our 8 trail camera deployments (a 9th is planned) are targeting unscaled hickories, stubs and live trees that show signs of damage or decline. The main goal is to capture images of Ivory-billed Woodpeckers by identifying potential foraging trees and targeting them in advance of their being scaled (a long shot but the best strategy I can think of). A secondary purpose, especially with targets that already show some scaling, is to test my feeding sign hypothesis by documenting work by Pileated Woodpeckers and Eastern gray or fox squirrels (a much easier task). These are the only other local species that have the capacity to remove large quantities of tight bark from the boles of mature living and recently dead trees, though I suspect this capacity is limited. Results from two deployments, one on a still living but compromised and extensively scaled hickory (4/29-6/6/2018) and the other on a sweet gum stub (5/3-6/4/2018), suggest to me that neither Pileated Woodpeckers nor squirrels are the source of the initial, extensive hickory scaling.

Part 1 will address Pileated Woodpecker activity on the hickory, followed by a brief discussion of my visit to the search area from June 6-11. Part 2, which should be up within a week or so, will focus on squirrels, especially their activity on the sweet gum stub, which I think is analogous to the Pileated Woodpecker activity on the hickory. These are preliminary findings that may be contradicted by data obtained in future, but thus far they support the suggestion that Ivory-billed Woodpeckers are the source of the initial scaling.

Introductory Note

Our PlotWatcher Pro trail cameras are dedicated time-lapse (as opposed to motion- activated) units. We set them to capture images at 20 second intervals, approximately between sunrise and sunset. The proprietary software makes it possible to create QuickTime movie versions of the time-lapse stills. The QuickTime versions are worth watching and are illustrative of behavior, but it’s important to remember that they are compilations of still images, not actual videos. Thus, it’s also worth stepping through them frame by frame. This will be an image heavy post but with a lot of analysis. I hope you’ll stay with it.

I am not planning to do posts on every review of every trail cam deployment but will post results that I think are a relevant or interesting to readers – PIWOs and squirrels spending time on scaled areas or removing bark, most or all woodpecker hits, mammals that are infrequently seen, identifiable birds, but not squirrels running up and down tree trunks.

Hypothesis

Before turning to a discussion of the trail cam imagery, I’ll take this opportunity to restate and elaborate on my hypothesis. The imagery and discussion will be familiar to some readers, but I hope the new data will shed additional light, even for those who know the material.

Initially, I hypothesized that certain types of bark scaling might be diagnostic for ivorybill. Bear in mind, my focus has been on identifying a diagnostic, not covering the full range of what Ivory-billed Woodpeckers might do, so my criteria, especially this specific restatement thereof, may be overly narrow. Over time, and based on trail cam captures of Pileated Woodpeckers and a squirrel doing some scaling that seemed to match Tanner’s descriptions, I have refined and limited the hypothesis as follows:

A particular and distinctive looking type of extensive scaling (large contiguous areas with bark removed) with associated insect tunnels on bitternut and pignut hickory boles – live trees, snags, and stubs – may be diagnostic for ivorybill. For recent work, the presence of large bark chips at the base of such trees is a related potential diagnostic.

The tree on the home page (shown below) is one example. Numerous insect tunnels, some with signs of having been expanded by woodpeckers, must be visible. The appearance of the scaled areas is such that I can recognize older work even in the absence of chips. Because standing hickories (in drier areas at least) are slow to decay and the bark can remain tight for years, older examples persist, and I’ve found many of those over the years.

 

 

 

 

 

 

 

The hypothesis is founded on Tanner’s descriptions of scaling (although bitternut and pignut hickories were absent from the Singer Tract) and on the anatomical characteristics of Campephilus woodpeckers versus those of Dryocopus or Melanerpes, which appear to lack the physical capacity to do this type of work or do it extensively. The characteristics of hickory bark – chemical composition, strength, tightness, and thickness – are also central. I think the same limitation applies to squirrels, at least on hickories. This is not to exclude squirrels and PIWOs from coming along after the initial scaling and expanding it.

It recently struck me that grain may play a major role in limiting Pileated Woodpeckers and squirrels from scaling on hickories. Both species seem to follow the grain when stripping bark. Bitternut and pignut hickory bark differs from that of many bottomland hardwoods in having criss-crossed grain, making it considerably harder to remove, except in narrow strips like these, presumably removed from the target tree by a PIWO last year.

Bark Strips

Based on the recent observations, PIWOs are more likely to dig through hickory bark to reach the sapwood than they are to scale it. I suspect it’s the case with the presumed 2015 PIWO “scaling” on hickory shown below, which is the only example of that type of work I’ve found. The differences may appear subtle in the photo, but they are more pronounced in situ; the work is patchy and discontinuous, and there are few or no exit tunnels. The chips at the base of this tree were small and included sapwood, indicating that this was actually shallow excavation with associated bark removal, something that is often and easily confused with true scaling.

 

 

 

 

 

 

 

 

 

 

 

 

Since 2013, we have found approximately 20 hickories that appear to have been recently or freshly scaled. Below are additional examples, plus some that were presumably several years old when photographed. In the case of the tree on the home page, the scaling was very fresh when found. I have not found any recent looking work of this type since March of 2015, though Phil found some last year that were probably scaled during 2016; one of these is the target tree in the sequences shown below. Steve Pagans has found several examples, but I’m not sure of any recent ones. Note the expansion of the exit tunnels, which makes it evident that woodpeckers have been active on the scaled surfaces.

 

 

 

A Cerambycid infesting the trees has been identified as Parandra or Hesperandra polita, a medium-sized, bole dwelling species with a 3-5 year life cycle.

 

 

 

 

H. polita remains, apparently of 2 adults, were found in one of the ivorybill stomachs examined by Cottam; it was collected in West Carroll Parish, August 19, 1903 and is referenced by Tanner. The adults of this species remain under the bark for some time after metamorphosis.

There may be additional subtle features, including chip characteristics and general appearance, that are relevant to other tree species and may be indicative if not diagnostic. A very nearly dead sweetgum, which had an intriguing cavity, from the old search area, is one example.

 

 

 

Trail Cam Captures – Hickory – April 29 -June 6, 2018

Over the course of this deployment, Pileated Woodpeckers were photographed on the target tree on 10 of 36 days, sometimes briefly and sometimes for periods of over 20 minutes. On some days in the latter part of the deployment, intervening foliage partially or fully blocked the lens, so it is possible there were additional visits. The camera is trained on the base of the scaled area, which extends to the broken top of the bole, and some of the sequences make it clear that pileateds are visiting the upper part of the scaled area as well. Phil Vanbergen found this tree last season; it is still living, although the sapwood is already somewhat punkier than what I’ve found on many longer dead hickories.

The first important point is that very little bark was removed over the course of this deployment, despite considerable time spent by Pileated Woodpeckers on the scaled area. The first two images are from the first and last days of the deployment for purposes of comparison. The new work is so minimal that it is only noticeable in the field upon close examination of the edges.

 

 

 

 

 

 

Pileated Woodpeckers were photographed on May 1, May 3, May 8, May 12, May 21, May 25, May 28, May 30, June 1, and June 4. A Hairy Woodpecker was captured on April 30 and on May 12. There were no squirrel captures on the scaled area. Individual frames and time-lapse films (when birds were present for more than a couple of captures) of the Pileated sequences follow. If you choose to watch/step through just one clip, I suggest the one from May 28, in which two birds are present, but viewing all of them will provide a better sense of what took place.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In addition to removing only a modest quantity of bark along the already scaled edge, despite being present on the scaled surface for over an hour altogether, it appears that the Pileateds are not actually stripping the bark but instead are excavating through it. This is also suggested by the quality of the bark chips on the ground. (The caption predates this imagery.)

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Bark and Sapwood Chips at Base of Live but Decaying Hickory. Presumed Pileated.

The same appears to be the case for the presumed Pileated “scaling” on hickory in the preceding section. It’s unclear what the woodpeckers were seeking in terms of food, since there is no evidence of current or recent Cerambycid tunnels. In any event, the sequences give evidence of what Pileated Woodpeckers do on hickories, and just how inefficient they are at removing bark.

In the images we captured last year from a nearby deployment (on another scaled tree Phil found, approximately 100 yards away), the Pileated appeared to be scaling bark rather than digging through it, and this too was a very inefficient process. It involved removing long narrow strips, distinctly different from the chunks of bark shown above. In a sequence Frank and I captured on the homepage tree back in 2013, a Pileated appeared on that very recently scaled tree but removed no bark at all; a Hairy Woodpecker also appeared and removed a very small piece. (Scroll down to the bottom of that post for the relevant images.)

The trail cam captures validate my prediction that the source of this most recent work is Pileated Woodpecker.

Thus, we have documented multiple instances of Pileated Woodpeckers foraging on trees suspected to have been initially scaled by ivorybills. None of the imagery thus far shows pileateds removing bark rapidly, efficiently, or extensively. Such bark as they do remove is from areas that are already compromised, although I have found a single example of hickory bark presumably removed solely by a Pileated Woodpecker; it differs markedly from what I’ve hypothesized is Ivory-billed Woodpecker work. While it is difficult to prove a negative, the data gathered thus far suggests that Pileated Woodpeckers do not or cannot extensively scale tight bark from hickories. I suspect they lack the ability to do so.

Other Interesting Trail Cam Images

While these trail cams have limited usefulness, except at close range, all of our cameras are close to their main targets. They are positioned close enough for me to recognize lizards and even insects on the trunk but not identify species. Identification problems can exist for small birds too. I suspect the bird in the image below is a Brown Creeper, though I’m prepared to be corrected as it is so poorly resolved. If it is a Brown Creeper, it would be the latest record for the species in Louisiana.

 

 

 

And this series shows what appears to be a bobcat, at the lower right.

 

 

 

Some Brief Comments on the Trip

Nothing strongly suggestive of Ivory-billed Woodpecker was seen or heard – no ambient sounds or responses to ADKs. Tommy Michot joined me on Saturday, Sunday, and Monday morning. We deployed the 8th trail cam, aiming it at the bole of a sweet gum snag that has a scaled area; I suspect Pileated Woodpecker was the source, and squirrel is also possible, but the decay state is within the range Tanner associated with ivorybill, so this will be a long-term deployment.

Low water made it possible for us to explore some previously unvisited areas. Tommy did several stakeouts where Matt made the recordings this year and where I heard wingbeats and had a possible sighting. On Sunday evening, he observed a Pileated near the sycamore roost where I photographed one in April, and we watched it flying away from the roost on Monday morning. No wingbeats were audible in either encounter, as would be expected for Pileated Woodpecker as opposed to ivorybill.

Temperatures reached the 90s by noon every day, depressing avian activity and making fieldwork unpleasant. There were heavy rains on the afternoon of Sunday, June 10, so the 11th was particularly challenging in terms of heat, humidity, and suddenly high water levels. I had a close encounter with a cottonmouth that dropped from a tree limb within a foot of my head, landing in a slough that had been dry the day before.

 

 

 

One personal highlight was the abundance of chanterelles, especially after Sunday’s rain. I came home with several pounds, though transporting them was a challenge, and I couldn’t keep them clean. Despite a little grit, they’re delicious.

 

 

 

Here are some additional photos. There’s one new example of extensive bark scaling from the upland area shown in detail; it is interesting, but I would not consider it highly suggestive. There was also some recent scaling on a sweet gum that may be more suggestive. I was using a rented 4/3rds camera and a lens with an effective 200-800 mm reach. I had trouble adjusting to the electronic viewfinder, but it was good to get a closer look at one of the cavities found this season. I also found feathers from a Pileated Woodpecker that was presumably recently taken by a raptor; this was in an upland area within 50 yards of where I parked. This is the first time in all my years in the field the that I’ve found PIWO remains.

Stay tuned for Part 2. Like this one, it will initially be password protected so that colleagues can review it before publication.