IBWO: It may be extinct

Less than a month ago, I thought the Ivory-billed Woodpecker was definitely alive and well in Arkansas. As I continue to examine the available information for myself, my doubt is growing. Like just about everyone else, I *want* the Ivory-bill to be alive, but I think we need to face a very real, very unpleasant possibility: the last one may indeed have died many years ago.

Let's start here, on the official Ivory-bill site:
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The team reported multiple fleeting views of the bird, a frame-by-frame analysis of two seconds of video footage, and possible recordings of the woodpecker’s distinctive double knock. This evidence has convinced many that at least one ivory-billed woodpecker survives in the Big Woods of Arkansas’ Mississippi River Delta.
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To me, the wording above suggests a certain lack of conviction, even by "insiders".

Look at this article:
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Finally, to put your chances in perspective, we logged more than 20,000 hours of searching for less than one minute of total Ivory-bill observation time.
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Ok, so somewhere between 8 and 18 sightings added up to less than one minute in total observation time. Those views really were fleeting--if you do the math, that would be an average of about 3-7 seconds per sighting.

According to Cornell's Supporting Online Materials, as of March 2005, all of their sightings had been clustered in four square kilometers of forest. According to my reading of the "The Grail Bird", those sightings occurred in this area. The vicinity was combed endlessly. It was monitored with numerous remote audio recording units as well as remote still and video cameras (with decoys). Tape playback and an elevated boom were employed. Despite this truly massive effort, not a single good view or photo was obtained.

Now why would there be 8-18 fleeting sightings, but zero non-fleeting sightings? Maybe the reason is that, to an experienced birder, a leucistic Pileated Woodpecker can only pass as an Ivory-bill if the look is fleeting. On a distant flying bird, birders would logically have a search image something like this: "level flight, dark bird with trailing white on the wings". If the bird is distant and your glimpse is truly fleeting, even birds like an American Crow with white wing patches, a Red-headed Woodpecker, a Wood Duck, or a Hooded Merganser could fit that search image. This could be especially true if you knew that other credible birders had reported Ivory-bill sightings in the area.

It's important to remember that many of the birders behind Cornell's "convincing sightings" were not 100% sure themselves that they had seen an Ivory-bill. In the "Grail Bird", Tim Gallagher wrote: "I was annoyed that so many people were throwing out percentages about how sure they were that they had seen an ivory-bill. Ron and David were maybe 85 percent sure; Jim Fitzpatrick was 98.5 percent sure; now here was Mindy saying she was 99 percent sure of her sighting."

No acceptable photographs have been taken in many decades. Some say the reason is that the Ivory-bill is so wary. However, in the 1930s and 1940s, the Ivory-bill was very rare but was not particularly wary, and many good photographs were taken.

If you're interested, take some time to read the information here. Written by Arthur Allen and P. Paul Kellogg, it details observations of Ivory-billed Woodpeckers in the 1920s and 1930s. With only a handful of team members, in an 81,000 acre swamp, they were able to locate several nest sites, take lots of clear photographs, and hang around the nests as the birds went about their lives. In the accounts of those days, I do see cases where a small team sometimes searched for a few days without success. Far more commonly, I see cases where they searched hard for a day or two, heard the call, located a roost, and then enjoyed repeatable good looks at the birds.

In the current hunt, we have a much larger team of experienced birders searching for over 20,000 hours. That effort would roughly equal a team of 15 people searching 10 hours a day, 10 weeks a year, for 2 years. Again, despite all the modern advantages mentioned above, not a single good view or photo was obtained.

If the Ivory-bills are really out there now, why have the massive search efforts in recent decades been so spectacularly unsuccessful? Have we completely lost our ability to find Ivory-bills, or are we searching for something that simply isn't out there?

As a thought experiment, let's try this. Imagine a large 160,000 acre tract in Arkansas with some good Ivory-bill habitat. Let's imagine that during the experiment, we somehow know that no Ivory-bills are present. Turn a rotating team of 15 enthusiastic, experienced, honest birders loose in that tract, and have them spend over 20,000 hours over a couple of seasons in an effort to find Ivory-bills.

Q. Would I expect them to get some fleeting glimpses of birds that might be Ivory-bills?
A. Absolutely. In an area that size, with that much coverage, I would expect some glimpses of leucistic Pileateds (and other species) that seemed very Ivory-bill-like.

Q. If they gathered 17,000 hours of audio data, would I expect them to find some sounds with sonograms that appear to match the Ivory-bill's distinctive "kents" and "double-knocks"?
A . Absolutely.

Q. Would I expect them to gather any acceptable photographs, or get any long, repeatable good looks at Ivory-bills?
A. No.