Distribution of Feeding Sign

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.


Trip Report – November 14-16, 2013

I made a brief visit to our search area from November 14-16. Because I was alone, I mostly avoided the more difficult and remote locations and focused on more accessible areas where possible encounters have taken place. This includes our current camera traps. The weather was a problem – steady moderate rain from 7:00-10:30 am on the 15th and early morning drizzle, moderate winds, and cloudy skies on the 16th, which was also the opening day of duck season. On that day, I ventured farther into the swamp and encountered one duck hunter in an area that appears to get very little human traffic. There was frequent gunfire throughout the morning and into the afternoon; however, even on this day when people were hunting for deer and ducks, I saw only four trucks parked along the parish roads, met two people on the road (one of them having just rescued two hunters who had gotten lost.) This was roughly the same level of traffic as we encountered on the opening day of squirrel season in October. Compared to other places I’ve visited in Louisiana, this is a fairly low level of human pressure, although between the gunfire and the weather, avian activity was suppressed on the 16th. Even the crows were less vocal than usual.

On the morning of the 14th, temperatures were in the mid-20s at sunrise. I visited the camera traps and found what may have been fairly fresh bark chips at the base of one; however, I couldn’t identify any areas of fresh scaling on the tree. Frank Wiley will be servicing the cameras and changing the cards in the near future. Time will tell whether anything was captured this time around. At 9:15, near one of the camera traps, I heard three kent-like calls from the ENE. They sounded very clarinet-like in tone, more so than some of the other calls we’ve recorded. The calls were very close together temporally, and I wrote that the cadence was “not quite what I’d expect.” At 12:55, I was in a different location and heard two more intriguing calls from the SSW (also SSW of where I was at 9:15). A Blue Jay was calling roughly simultaneously from a different direction. I consider both of these incidents ‘weak possibles’ because I was alone and because the calls were so few in number.

On the 15th, I spent most of the morning in the field despite the rain, giving up at 9:30 am. The skies cleared at around 11, and I spent part of the afternoon exploring some habitat to the east of our hot zone. One of our group members has made several visits to this section, but I had only spent one morning there. Because it was unfamiliar territory, I chose to walk the bank of the bayou that bisects it. The understory along the bayou is dense and predominantly comprised of holly, which made for tough walking (and also made it difficult to look for and photograph feeding sign.) I was only able to go about ¼ mile in an hour at which point I turned back. Although I covered very little ground I did find an abundance of feeding sign, including a recently dead snag that had been scaled in the manner that I think is diagnostic, and multiple examples of the scaling on higher branches that is consistent with what Tanner described. The high branch scaling appears to be older, but the work on the snag seemed recent, with fresh bark chips on the ground, so it may be an active feeding site. I’ve included some images to illustrate.

Snag11:15 Snagdetail11:15
bigchip High11:15 Tanneresque11:15

Due in part to weather conditions (which made looking for feeding sign a challenge) and gunfire I did not see or hear anything significant on the 16th, although I went deeper into the swamp following a familiar route. About 2.5 miles in, I came very close to stepping on a large cottonmouth as I stepped over a downed tree. Its mouth was wide open, and it was ready to strike when I spotted it. Just a reminder of how dangerous it can be to wander around alone in the swamp.

Moccassin