Friday, January 12, 2007

ENV: Florida Ivory-bill search

An intriguiing update from the Florida Ivory-bill search . . .
Update 1/07/07

A report from the Auburn/Windsor Choctawhatchee River Ivory-billed Woodpecker search. This is an informal update. Details of sightings and sound detections mentioned in this report will be published later.

It’s been a whirlwind December and beginning of the New Year for our search group. We’ve now re-established our tent camp that is the base for our search operation, and all of our paid searchers as well as several volunteers have been in the forest looking for ivorybills. We had planned to have cavity searches largely completed by the end of December, but we barely got them started by that time. Brian Rolek and Rusty Ligon were incredibly busy taking classes, teaching classes, and trying to order equipment and get things organized. The few dozen cavity transects that we completed out of several hundred that need to be conducted indicated that we are going to be dealing with a daunting number of holes in trees. At one point I estimated that we might have 3500 cavities over our entire search area, but this projection was made based on some particularly cavity-rich transects. We will probably end up with cavity total somewhere between 1000 and 2000 if we cover our entire search area, but that stills seems overwhelming. These totals are for cavities, not cavity trees. The numerous large cypress with ten or so cavities each is largely responsible for this enormous number. Obviously these are not all active ivorybill cavities or cavities dug by ivorybills. This is the number of cavities estimated to be 3 inches or greater in diameter. This forest is simply full of big cavities. A relatively small subset of these cavities are very big—over five inches in vertical dimension—and then a subset of these large cavities are fresh and have a shape like the ivorybill cavities photographed in the Singer Tract. Despite having huge areas of forests still to survey, we have found more than twenty fresh, big, correctly shaped cavities and we are starting to monitor these high-scoring cavities with Reconyx cameras.

In November, Dr. Bruce Lyon, an ornithologist from UC Santa Cruz, and his former grad student, Jeff Barna, visited our site. They camped in the area for a week before we established our permanent camp, and Jeff had several ivorybill sound detections. Jeff also had an ivorybill fly over his head at treetop level just at sunrise. He only saw the silhouette of the bird but he could clearly see that it was a large woodpecker with long wings, a thin neck and a long wedge-shaped tail. It had a straight, stiff-winged flight pattern. He was confident that it was an ivorybill and not a pileated woodpecker. Since we have established our remote camp in December we have had a flurry of sound detections—at least 15 independent double knock and kent detections as of Sat (Jan 6 when I paddled out of the swamp). We have also had three recent sightings including two by Bob Anderson, a Virginia birder who visited our site as a volunteer. Bob’s second sighting was particularly good. He observed an ivorybill 25 meters away as it flew up from the ground or from a very low perch. He clearly saw the broad band of white on the trailing edge of the wing of a large black woodpecker. He reported that it had a stiff-winged flight and that he heard loud wing flaps as it flew away from him.

On Christmas Eve, Tyler Hicks got an outstanding look at a female Ivory-billed Woodpecker. Only three people were in camp that day—Drs. Greg and Diane Lewbart and Tyler. Tyler heard double knocks in early morning, and using his radio he called Greg and Diane toward the location. Diane was first on the scene and she heard three kent calls. Things then quieted down and everyone went back to cavity surveys. An hour or so later, Greg and Diane heard four double knocks southwest of the area birds had been detected, and they called Tyler. Tyler rendezvoused with Greg and Diane and headed off in the direction they heard the double knocks. While hiking along a narrow fast flowing channel he heard two kent calls. Tyler was hiking along the channel and it began to rain. Tyler tucked the SLR under his jacket and stealthily hiked in the direction of the kent calls. As he came around a bend in the channel, he saw an ivorybill on the trunk of a tupelo. It was only about 40 feet away. Tyler could clearly see the “ivory-white” bill on the bird—he said the pale bill “glowed” against the dark trunk of the tree. The crest of the bird was black. He’s sure. No red. The bird presented a profile so he saw one dorsal stripe running from the head to the back. The lower portion of the back of the perched bird was brilliant white. The bird paused on the tree for just a second and then fled. As it launched off the trunk and flew off Tyler could clearly see the broad white trailing edge covering the secondaries and innermost primaries of the dorsal wing surface. In flight, it had a long pointed tail and a long neck which he described as “like a pintail duck”.

Tyler’s encounter was a great photo opportunity, but the camera failed us. Tyler’s SLR was set to auto focus and it focused instead of taking photos during the couple of seconds the bird was in front of him. This is extremely frustrating for all of us, but we are getting very close to a photograph of these woodpeckers. We’ll have a photo or video soon. Having a larger search crew is making all the difference. We are able to locate and track these birds now.

Tyler’s sighting cannot be dismissed as a misidentification. The details reported by Tyler absolutely rule out any other species of bird.

Things are extremely busy for all of us but I’ll try to post an update each week during our search. Geoff Hill, 1/7/07

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