The Ivory-billed Woodpecker was front and center at another meeting of the American Ornithologists’ Union yesterday, the last day of the 2007 meeting at the University of Wyoming, Laramie.
Auburn University ornithologist and Florida Ivory-bill search-team leader Geoffrey Hill and team member Brian Rolek, also from Auburn, made 15-minute presentations after lunch.
Hill went first, recounting evidence for the persistence of the woodpecker along the Choctawhatchee River in northwestern Florida. Rolek followed. He described a sighting of the woodpecker that he reportedly made in May and then showed a brief video clip, captured, accidentally, at the time of the sighting. Hill said the team’s data and the video will be posted soon on his website at Auburn and on Dan Mennill’s website at the University of Windsor.
Here’s what I was able to record as Hill and Rolek spoke:
Hill reported that the team concentrated their searches in two locations along the Choctawhatchee in 2007: at the mouth of Bruce Creek and farther north at Old Creek. Bruce Creek was the site of Rolek’s first reported sighting in May 2005, described (but not named) by Hill in our magazine in February. (See “The Other Guys”.)
The team was organized into four components: a group in the south led by Rusty Ligon, with 6 members; another in the north led by Rolek, also with half a dozen fellow searchers; a Reconyx camera team spearheaded by James R. Hill III and one assistant; and an automated listening group headed up by Karan Odom.
The focus early in the year was on finding cavities. Geoffrey Hill said the team searched 1,480 transects and covered 12 square miles of forest by late January. For their effort, he said, the team found 3,147 holes three inches or larger but no nest. He characterized the effort, bluntly and perhaps belatedly, as a “big waste of resources” and said from January to May the team concentrated on searching for woodpeckers.
A team member told me that that search produced 12 sight reports. Hill talked about only three. The first, a sighting of a perched female, was made on 24 December 2006 at the Old Creek site by Tyler Hicks, whose pencil sketches were shown. The other two, both of woodpeckers in flight, were made by someone named Bob Anderson, whom Hill referred to only as a “visitor from Virginia.” Anderson reported seeing an Ivory-bill on 25 December, the day after Hicks’s report, and again on 3 January 2007.
Hill said members of the search team also reported hearing 30 double-knocks and 17 kent bouts. He referred to them as “in-life detections” to distinguish them from sounds recorded by automated listening stations. The team deployed 16 of these between 5 January and 22 May, Hill said, and produced 35,000 hours of recordings. About 26,000 hours of recordings (74 percent) have been analyzed to date.
The recordings include both double-knocks and kent calls, Hill said. These the researchers classified from 1 to 5, assigning 5’s to sounds most likely to have been produced by an Ivory-bill. The year’s recordings included 54 double-knocks and 99 kents that the searchers thought merited a 3, 4, or 5, Hill said.
The search team also deployed an unbelievable-sounding number of cameras -- 315 -- and these, Hill reported, produced a perhaps even more unbelievable-sounding sum of 7 million photos. (Did I hear this right? If you heard differently, please let me know.) Among them was only one image that could possibly be an Ivory-billed Woodpecker (or woodpeckers). If you read Birding, the journal of the American Birding Association, you’ve probably already seen it: It was captured in November 2006 without a human finger on the shutter release and published as the photo quiz in the July-August 2007 issue (vol.39, no.4, p.96 and downloadable here).
Hill said the snag near the center of the picture was what the camera was aimed at. He stopped short of identifying the three blurry birds, saying only that he thought they were flying toward the camera, not away from it, and that they had woodpecker-like long wings, heavy tails, and long bills.
In response to the same old question, Why is it so difficult to get a good photo of an Ivory-billed Woodpecker? Hill gave the same four reasons: The woodpecker is quiet; it occurs in very low density; it prefers forests and avoids open areas; and it flees from people. With this bird, it’s “the other side of the tree and away from people,” he said.
Rolek, whose 15-minute presentation followed Hill’s, said he saw an Ivory-billed Woodpecker at Old Creek at 4:45 p.m. on 19 May 2007. He described the sighting and displayed pages of his notebook on which he had sketched the bird and described the event, and then he showed the video, taken from a digital camera mounted in a kayak at the time of the sighting.
In it, Rolek can be seen paddling a kayak away from the camera and beneath a diagonal-leaning tree or sizable fallen branch. In contrast to almost all the swamp images I’ve seen in the past year or two, the scene here was sunny, not funereal. As Rolek nears the tree, a bird flies from it and quickly out of the camera’s image area to the upper left. Rolek spots the bird after it exits the frame and points at it.
The amount of time the bird is on screen can’t be more than a second or two. It was fast. When the video was played the first time, people in the audience laughed self-consciously. Not many saw it. When the video was replayed and slowed down, I saw a black bird with black leading edges of the wings and broad, bright white patches on the trailing edges of the wings.
Was it an Ivory-bill? I don’t know. Isn’t the white on an Ivory-bill’s wings supposed to be visible on both the upstroke and the downstroke? Didn’t I see black then white then black then white as the wings flapped? Would I like to take another look? You bet.
Rolek tried to dispel the idea that the kent calls and double-knocks they recorded could have originated with non-animal sources. These, one presumes, would have produced detections at night, he argued, yet the listening stations made no detections in 1,500 hours of nighttime recordings. Both he and Hill also said that there were no puddle ducks in the region.
Rolek stated that the probability of detecting a kent call was 7 in 1,000 hours of scanned audio, that the probability of detecting a double-knock was slimmer, only 4 in 1,000 hours, and that the chance of hearing a kent and a double-knock together was thinner still -- 1 in 5,000 hours of scanned recordings. Yet that’s what Rolek and Hill said they were able to detect on more than one occasion. They displayed two or three charts that demonstrated that both kent calls and double-knocks were detected at the same time or very close to it.
And Rolek said Tyler Hicks’s Christmas Eve sighting was part of a similar cluster. At 7:40 a.m., a search-team member heard a kent call. Double-knocks were heard in the same area at 9:29 a.m. Hicks reportedly made his sighting in the same area only a few hours later, at 12:34 p.m.
Well, that's about it for now. I'd be interested in your comments. -- C.H., from Laramie