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Mystery Bird Meets Imperial Woodpecker – Trail Cam Photos Revisited (Part 2)

If you haven’t done so already, please read Trail Cam Photos Revisited for a more comprehensive discussion of the image that’s central to this post (including an explanation of our conclusion that the mystery bird is larger than a Pileated Woodpecker). At the time of writing, I didn’t envision doing a follow-up, but the nagging sense that the Rhein Imperial Woodpecker film might be even more relevant than I thought initially led me to go through the film again and pull an additional frame that showed the body profile, with neck extended, more fully and accurately. While I added an update to the original post that included a brightened composite for comparison, there’s a bit more to say.

We’re aware that many (perhaps most) in the scientific and birding communities will accept nothing less than a clear, high quality photograph (or series of photographs) or video. We’re also aware that many people will dismiss any post-processing whatsoever, even when intermediate steps are shown and the processing is relatively limited (in this case only involving the removal of motion blur). I must add, as should be evident from the images in this post, my skills with photographic post-processing tools are very limited. (Patricia Johnson, my wife, had to talk me through the rotation of the images in Photoshop.) Nevertheless, we think comparing the de-blurred mystery bird with frames from the Rhein film showing an Imperial Woodpecker in flight with similarly positioned wings makes a compelling case that our mystery bird is indeed an Ivory-billed Woodpecker.

Our choice of location for the game cam deployment was not random. As with this image (from our old search area), which was obtained a week after a sighting in the same location, the camera was deployed in an area where we’d had recent possible contacts – multiple double knocks (scroll to the end of the trip report) heard within a few hundred yards before and during the deployment, about a week before the image was captured. We also recorded an apparent double knock on the day we retrieved the cards. Thus, in both instances there was a close temporal association between a putative encounter and obtaining (at worst) a strongly suggestive trail cam capture. But I digress . . .

To return to the Imperial Woodpecker, these two screen captures are the most salient.

Screen cap of Imperial Woodpecker in flight, shortly after take-off, at a different angle, but with similar wing position.

Screen capture of Imperial Woodpecker in flight, shortly after take-off, at a different angle, but with similar wing position.

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Screen capture of Imperial Woodpecker in flight.

I was unable to find frames in the film that replicate the angle from which the mystery bird was shot. In the first of these two frames, the bird is flying downward and is angled slightly away from the camera, obscuring the bill and foreshortening the neck and tail. The second is a ventral view from behind, and the bird is angled downward. Our mystery bird is ascending and is seen in profile. Nonetheless, the similarities in both the extent of white on the wing and physical structure are striking. This becomes even more apparent when the Imperial frames are rotated and sized to match the mystery bird. Be sure to click on the images to see the full sized versions.

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.

Rotated, resized image of Imperial Woodpecker in flight. In the original, the bird is angled downward and slightly away from the camera obscuring the bill and foreshortening the profile.

Imperial Woodpecker in flight. Rotated and re-sized for comparison with mystery bird.

Imperial Woodpecker in flight. Rotated and re-sized for comparison with mystery bird. Although this is a more ventral and posterior view, the similarities in structure are dramatic.

I concluded the previous post by observing, “We realize that this is far from conclusive but can think of few alternative interpretations, all of which are problematic.” Based on the comparison with known stills of the Imperial Woodpecker, I am now firmly convinced that the mystery bird is an Ivory-billed Woodpecker and do not think there’s a reasonable alternative explanation. Frank’s comment was, “People have been executed on far flimsier evidence.”

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Trail Cam Photos Revisited

Frank recently found a series of images from our trail cam deployment discussed here. These photographs, taken with a second camera, are of very poor quality, but they show what is clearly a Pileated Woodpecker on the target snag. Frank’s discovery led us to re-examine some of the images discussed in Frank’s post and elsewhere on the site because they gave us a reference object to assess the size of the birds in two other low quality trail cam photos.

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Based on this reference object and informed by outside evaluations, we’re confident that the “mystery bird” discussed in this post is in fact a Red-headed Woodpecker. (We still concur with the author’s analysis of the other image discussed in the post.) The bird is clearly behind the tree but not very far from it, and it is simply too small to be anything else. Despite my initial interest in this photo, I had been leaning toward Red-headed based on feedback from a number of people and on the length of the tail.

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I have always thought that this was the most intriguing image in the series, although some reviewers have disagreed.

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I’ve also always believed that the bird was behind the snag and in front of the somewhat more distant small branches, which would mean it’s large. Frank, who has by now reviewed perhaps 1 million trail cam images, has always agreed with this interpretation.

Frank’s discovery of the Pileated sequence led me to re-examine this photograph and dig a little deeper. One reviewer suggested that motion blur made it impossible to make any judgments about size or distance from the camera. In response, I did a bit of research and found Focus Magic, a forensic program designed to reduce or eliminate motion blur.

The results of running the image (bird only) through Focus Magic are interesting. (No other processing was done.)

Image processed with Focus Magic. Setting for a 35 degree angle and a blur distance setting of 13 out of 20

Image processed with Focus Magic. Setting for a 35 degree angle and a blur distance setting of 13 out of 20. The object was selected using the lasso tool in Photoshop, making it possible to de-blur the moving bird without affecting the rest of the image.

I shared this processed image with Louis Shackleton, a professional photographer friend who has a background in ornithology. I also sent Louis one of the Pileated images and these two other trail cam photos that were taken within an hour and ten minutes of the first, on December 7, 2014.

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The first of these shows what we believe to be either a Red-headed or an Ivory-billed Woodpecker in flight and behind the snag. The other shows an intriguingly shaped but badly blurred bird in flight, passing between the camera and the snag. (The motion blur in this image is so severe that I was unable to make any meaningful improvements using Focus Magic.) Louis had this to say about the photographs he reviewed:

“ . . .I concur that the first image is the most interesting. Comparing that and the image of the PIWO on the tree, it seems to be larger, [and] as you say, I think it’s beyond the snag. The second image, it’s also beyond the snag, but there’s no way to gauge how far. The third image, it’s definitely in front of the snag, but also no way to tell how far in front.”

Frank and I interpret the photograph as follows. It shows a long-necked, long-tailed, slender-bodied bird that is somewhat larger than a Pileated Woodpecker flying upwards at about a 35 degree angle. There is white on the trailing edge of the wing, although it’s unclear whether this white is on the underside of the left wing, the upper side of the right wing, or both. We do not believe this white to be an artifact, since it appears faintly in the unaltered image; it becomes more fully resolved when the blur is eliminated; it is still present even at a blur distance of 20, the highest Focus Magic setting, when image clarity breaks down significantly.

Focus Magic processed image with blur distance set at 5

Focus Magic processed image with blur distance set at 5

Focus Magic processed image with blur distance set to 20

Focus Magic processed image with blur distance set to 20

A couple of considerably more ambiguous features are also intriguing. The bird appears to have a fairly distinct and sizeable bill, and in the Focus Magic iteration in which the white is most clearly defined (blur distance 13), there’s a hint of red on the head, although this could easily be an artifact. While the William Rhein film of an Imperial Woodpecker in flight was shot at a different angle, we think the profile and structure of the IMWO in that footage strongly resemble our mystery bird.

Screen capture of Imperial Woodpecker in flight

Screen capture of Imperial Woodpecker in flight from the film by William Rhein

Screen cap of Imperial Woodpecker in flight, shortly after take-off, at a different angle, but with similar wing position.

Screen capture of Imperial Woodpecker in flight, shortly after take-off, at a different angle, but with similar wing position.

Edited to add: To facilitate comparing our mystery bird with the Imperial Woodpecker in the frame shown above, I’ve created a composite image using the 13-35 de-blurred image, which I’ve also brightened. In addition to flying downward, the Imperial is angled slightly away from the camera, foreshortening the neck and obscuring the bill.Composite

It has been observed that there’s nothing to prove our mystery bird is a woodpecker, and that’s a fair point; however, the size, shape, and apparent white on the back of the wing are all consistent with Ivory-billed Woodpecker. We realize that this is far from conclusive but can think of few alternative interpretations, all of which are problematic.


Kent-like Calls Recorded March 2, 2013

Since summer is here, and things are slow, I’ve reconsidered my decision not to post audio obtained in the course of our searches (although I’m not sure I’ll repost old audio from the original search area.) We did not record anything of note during 2013-2014, although we did have a number of auditory encounters. It’s not feasible to keep a recorder running at all times, so when interesting ambient sounds occur, it’s only possible to capture them when they go on for an extended period. In these situations, it’s a judgment call as to whether to approach the source of the sounds, try to record them, or a mix of the two.

These recordings were made on March 2, 2013, and I have included my notes to provide details and context (location redacted.) On the morning clip, the calls can be heard at approximately 0:03, 0:17, 2:04, 3:36, and 3:47 (two calls in very close succession with the interval almost indiscernible to the ear but evident in the sonogram). On the afternoon clip, the only call captured is at approximately 0:52. On the morning clip, there are toots on a clarinet mouthpiece at approximately 0:25 and 1:30, so beware if you’re listening on headphones. The first clip can be played directly from this page. Click on the link to play the second in its own window. I can only hear the call on the second clip with headphones.

Although the duration of the calls appears to be consistent with the Singer Tract recordings, the base frequency is considerably higher, approximately 920 hz.

John Henry and I were ***** on Saturday March 2, 2013. Conditions were mostly cloudy and cold.* Winds were strong (gusts probably around 20 MPH and not many birds were calling). The morning had been active, but as winds picked up, birds went quiet. At approximately 10:15 am, several crows were calling loudly, but I heard 2 intriguing calls behind the crows. I asked John to stop and be quiet. The calls continued, sporadically, for the next 30-45 minutes. I was able to record some of them. We both estimate the distance at around 200 yards and agree that two birds were involved. We both agreed that the calls were mobile and over the course of the sequence, they came from at least three directions. We tried to follow the calls but did not see anything.

Most calls were singles, but in a couple of instances, a first call was followed by a second one within a couple of seconds. The pitch of the second call seemed lower. The duration of the calls seemed to be short. They lacked the intensity of the Singer Tract recordings, but were clearly not Blue Jays, nuthatches, or tree squeaks.

I blew on a clarinet mouthpiece. The calls continued, but neither of us had the impression that there was a response.

At the end of the sequence, John heard two additional calls that I missed, and we found large bark chips at the base of a tree that was in the vicinity from which he had heard the calls. We had walked through this exact location before the calls began and had not noticed the chips (which I normally would have done.)

Between us, we heard a minimum of 18 Ivory-billed Woodpecker-like calls in the morning.

We left the area and returned late in the afternoon. At approximately 5 pm, we were at the spot where we found the bark chips. At this time we heard approximately a dozen more of the same calls and were able to record a couple. The first call I heard seemed a little off, as the note seemed to be doubled, one in immediate succession after the other.** This only happened with the first one. The others were virtually identical to those heard earlier in the day. A white-breasted nuthatch called during this sequence, and there was no possibility of confusion.

*The two nearest weather stations reported lows of 27 and 30 and highs of 47 and 49 respectively. Temperatures in the search area were likely slightly lower. When the morning calls were recorded, temperatures were in the mid-30s.

**This was what I wrote at the end of the day, without consulting any literature. Of course doubled calls are described by Tanner and occur on the Singer Tract recordings.

We are not claiming these as Ivory-billed Woodpecker calls, but several ornithologists have been unable to identify them. The sound and base frequencies are consistent with calls recorded in the old Project Coyote search area.

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Edited to add: Here’s a sonogram showing the two calls that came in very close succession at 3:47 on the morning recording. I was unable to tease out anything but the base frequency. Sonogram-1 copy


Imperial Woodpecker Foraging

Cornell has an enhanced extract from the 1956 William L. Rhein Imperial Woodpecker film. The extract was included in the supporting materials for the Auk paper that discusses the film. I had overlooked it until now and suspect that others may have missed it.

In this clip, the bird can be seen scaling bark from what looks like a living pine. While the quality of the film is poor, even with the enhancement, the upper section of the scaled area shows signs of earlier excavation. The bark chips removed in this segment appear to be fairly small, especially when compared to some of the larger one’s we’ve found, but the speed and efficiency with which the bird removed the bark, as well as the way in which she did so, may be relevant to the scaling we’re seeing in Lousiaiana.