Distribution of Feeding SignPosted: November 24, 2013
There may be some value in considering the distribution of the particular type of suspected Ivory-billed Woodpecker foraging sign that I’ve discussed in my recent posts. For the purposes of this analysis, I will limit myself to one very narrow category of bark scaling: extensive work done on the boles of live or recently dead trees (species undetermined in some instances; at least one identified as hickory.) Bark has been tight when examination is possible, and large exit tunnels are abundant. The appearance of the work is consistent – no underlying excavation, no sign of scaling in layers, clean edges.
Two of the trees are in the southwestern section of our search area. This is the general area where I’ve had most of my auditory encounters, although it’s also the area where I’ve spent the most time.
Three of the trees are to the northeast of this pair; two of these were in an inaccessible location and were photographed at a distance of about 40 yards. While they could not be examined for bark tightness, the appearance of the work was consistent with the other examples included in this summary.
Two of the trees are to the east of a parish road (this includes the one discussed in my November update.)
One tree is in the northernmost area we’ve visited and where we’ve spent the least time. Auditory contacts in this area have only involved one source.
The as-the-crow-flies distances involved strike me as being potentially significant. The shortest distance between any two trees is about a quarter mile. The two southwestern area clusters are about half a mile apart at the closest point. From the easternmost tree in these two clusters to the examples east of the parish road, the distance is ~1.35 miles and hence about 2 miles from the westernmost trees. The area to the north is about 2 miles northwest of the easternmost scaling and about 2.8 miles north of the southwesternmost tree.
In 2012, there was a cluster of scaling between approximately .5 miles farther south. The two series of kent-like calls involving two sources heard and recorded in March 2013 came from even farther south.
The distances are much greater than would be expected if a lone pair of Pileateds were engaging in anomalous feeding behavior (there would probably have to be at least three pairs of PIWOs involved.) They’re roughly consistent with the home range Tanner gave for the Singer Tract pairs.