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What’s in the Cavity? A Possible Second Bird in a Couple of Old Trail Cam Photos

Regular readers are no doubt familiar with some of the images shown below. The “neck bird”, which was photographed in our old search area in August 2009, has been discussed in a number of posts. I think it likely shows a female Ivory-billed Woodpecker, something that became clearer once I satisfied myself that what appeared to be red in the crest (in the wrong place for either Pileated or ivorybill) was likely an artifact and that the crest appears to be all black, as shown in the enhanced image below. The original captures (the first taken a minute before the neck bird appears and the second showing the neck bird) are immediately below that for those who haven’t seen them.

IMG_1096-Edit-Edit-Edit-Edit-Edit-Edit-Edit-Edit-EditTopaz+processed+neck+bird+copy-magic copy 2

Processed Detail of Image 1096, August 11, 2009

Years after the capture and probably after the first post about this image in 2014, I noticed that an object suggestive of a light colored bill was visible in both frames, apparently protruding from the lower cavity in the snag to the right of center. While I have shared this information privately with a number of people and did a vague Facebook post about it a couple of years ago, I’ve hesitated to blog about it or discuss it in detail. That changed after I showed it to Jay and Erik before we parted company on my last trip to Louisiana. When Erik suggested that the object might be a vine or some other intervening vegetation, I decided to go back through my files. I discovered that Frank had sent me several additional captures from the same deployment. I examined these frames and found that the apparent bill was absent from all of them.

 

Below are details from frames 1095 and 1096 showing the apparent bill, which changes position slightly from one frame to the next. The time lapse interval between images was 1 minute. Again, the cavity in question is the lower one (below the fork) in the snag to the right of and behind the one on which the neckbird is seen in 1096. These snags are black willows (Salix nigra), and the neck bird snag (with the large cavity apparently being used by a squirrel) fell between November 2009 and January 2010. I’m also posting the close-ups in tiled mosaic format so they can be viewed side-by-side.

For this round of image processing, I used Let’s Enhance, which enabled me to retain a large format for cropped and zoomed versions.

IMG_1095-Edit-2-EditTopaz+processed+neck+bird-magic. copy

Detail from 1095 – Note apparent light colored object (possibly a bill) apparently protruding from an bisecting the lower cavity

 

IMG_1096-EditTopaz+processed+neck+bird-2-magic copy

Detail from 1096, captured one minute later. Note slight change in position of the possible bill.

Next are two details from images captured a few days later. The possible bill is nowhere to be seen. The same is true for the other captures from this deployment. Thus intervening vegetation and artifact can be ruled out.

2135DetailEnhanced

Detail from image 2135, captured August 14, 2009. Note the absence of the apparent bill that appeared in images 1095 and 1096 captured three days earlier.

2507DetailEnhanced

Detail from Image 2507, captured on August 16, 2009. Again, note the absence of any object in the lower cavity.

To summarize, the following two photos show what appears to be a bill in the cavity:

2009-08-11 7:48 am  (image 1095.jpg)

2009-08-11 7:49 am  (image 1096.jpg – the neck bird photo)

The following photos show a cavity with no apparent bill:

2009-08-14 6:19 am

2009-08-14 6:20 am

2009-08-14 6:21 am

2009-08-14 4:06 pm

2009-08-14 4:07 pm

2009-08-15 6:20 am

If this is a bill, it appears to be large and light colored, consistent with Ivory-billed Woodpecker. Both Erik and I noticed that, in frame 1095, a topmost part of the white dorsal stripe also may be visible. When Jay first saw the photos, he was reminded of the Neal Wright photos from Texas. Some images from the Singer Tract also come to mind.

 

Thus, this apparent bill resembles those of known ivorybills in cavities – in size, shape, orientation, and contrast. It is present only in frames 1095 and 1096 (the latter of which shows another possible ivorybill); it changes position over the course of a minute, from one frame to the next. There is no way to be sure images 1095 and 1096 show an Ivory-billed Woodpecker in a roost hole, but these facts, especially taken together, suggest that they may.

When I look back at what transpired in the old search area between August 2009 and November 2010, when the adjoining parcel was logged, it’s extraordinary. I may revisit those events in a future post or two.

For now, I’ll close by tying this into the Bits and Pieces series. The old search area is not one that would be deemed suitable under most habitat models. The images above were captured in a stand of black willows at the edge of a bean field. The other trail cam capture, where I had a sighting, was also within perhaps 30 yards of that field. When I look back at my assessment of the habitat from the time, I think I somewhat naively overstated its quality; however, there was a good deal of dead and dying timber, and it was in close proximity to several much larger habitat patches. If we did indeed capture ivorybills with our trail cams, their presence in this area may point to how the species has been able to adapt to more fragmented habitats.

Thanks to Erik Hendrickson for his input on this post and his help in making it clearer.

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Cavities and Context

As many readers of this blog are aware, I’ve been actively searching for ivorybills since 2007 and have been obsessed with foraging sign and cavities since my first days in the field. Over the years, I’ve looked at bark scaling and cavities both in and out of suspected ivorybill territory and have developed and refined a hypothesis about what constitutes diagnostic ivorybill foraging sign. I have come to believe that no such diagnostic category exists for nest or roost cavities, although size, shape, and other contextual elements can support a suspicion that a given cavity is an ivorybill nest or roost.

The cavity cluster we found in May 2014 has characteristics that are encouraging – size, shape, tree species, bark scaling in the vicinity – and one of the cavities resembles a known Ivory-billed Woodpecker nest. This is more than ample reason to survey the surrounding area very carefully (and I’m eager to get back out there), but whereas I feel personally confident that the dramatically scaled hardwoods in our search area were fed on by IBWOs, the mere presence of intriguing cavities is nowhere near as compelling for me.

Similarly, while I suspect that Frank Wiley found a recent nest and at least a couple of roost holes in our old search area, this view is informed more by the associated conditions than by the qualities of the cavities themselves. The suspected nest was in a tree that was heavily scaled and excavated in a way that was strikingly similar to a nest tree found in the Singer Tract, and this is more important than the size and shape of the cavity itself. The two suspected roost holes were in close proximity to one another, and were certainly large enough, but were dramatically different in appearance. There are several facts that are more significant than size or shape. We had a camera trap that covered both trees for a period of several months, and no Pileated Woodpeckers were photographed using the trees in question; the only image we obtained was suggestive of ivorybill but inconclusive (no images of either species were obtained from the suspected former nest tree, even though there were active PIWO roost cavities within 20 or 30 yards); in addition, we found an abundance of feeding sign in the area and had multiple auditory encounters and possible sightings within a few hundred yards of the suspected roosts between August 2009 and April 2010.

oldareacavity2

cavity 2 reportWillow Cavities, East-Central Louisiana 2009. Photos by Frank Wiley.

In examining the images of the suspected roosts and comparing them with other images of woodpecker cavities, I came across a photograph of a Crimson-crested Woodpecker (Campephilus melaneoleucos) near a cavity and was struck by the fact that it was almost identical in appearance to one of our suspected roost holes. I did some further research and found an image of a Pileated Woodpecker nest that was quite similar, if not quite as close a match.

All of this leads me to think that, while it’s important to look for suggestive cavities, this should not be the top priority. I’d encourage other searchers to focus on feeding sign, habitat characteristics, and local reports above all. The limited available information suggests that feeding sign is what led Allen and Kellogg to the Singer Tract birds and that it’s what Kuhn and Tanner looked for. Pileateds will use big cavities (and I’ve even seen White-breasted Nuthatches nesting in holes that look perfect for ivory bills). While finding a nesting or roosting ground will be central to documenting the ivorybill if it persists, cavities alone will not point the way.