Trip Report December 16-21, 2016, Part 2Posted: December 25, 2016
Part 1 of this report is here.
Patricia opted to take the day off on the 19th, so I went out on my own and covered a lot of territory. I had been thinking hard about the hickories and the fact that, in virtually all cases, we’ve seen indications that bark is removed from these trees and stubs within a very brief period or perhaps in a single visit and that other woodpeckers don’t seem to begin working heavily on these trees for extended periods, sometimes for years. Except for changes in color due to exposure to the elements, some of the scaled surfaces we associate with Ivory-billed Woodpeckers can retain their distinctive appearance for at least three years and more likely five or more.
Steve Pagans later explained that this is due in large part to hardening by compression; hickory wood is hard and dense to begin with, and when a tree or stub is leaning, the wood that’s absorbing more weight becomes even denser, harder, and more impervious to rot. Thus, on many of these trees, Pileated Woodpeckers will have worked on the rotting side, sometimes extensively, while the compressed side remains very hard and virtually untouched by woodpeckers.
I examined and marked as many of these trees as I could over the remainder of the trip. Unfortunately, we did not find any of this scaling in the 2015-2016 season. Trying to find more of it this year and trying to find a way to identify potential target trees before they’re scaled will be priorities for me.
I plan to write about this work on hickories and what I think it suggests in an upcoming post. For now, suffice it to say that these particular snags and stubs are a kind of twofer having the decayed substrate that’s preferred by Pileateds and and the hard wood that, following Tanner, is preferred or used exclusively by ivorybills. As noted elsewhere, some bark on these snags and stubs can remain tight for years, and on one of the trees I examined, it was still difficult to remove, even when it had reached a point at which some of it would crumble to powder when it was being pulled off. More importantly, the harder surfaces show modest expansion of exit tunnels and targeted digging work that appear to be associated with the initial scaling (as in the hickory on the homepage and the one in Steve’s photo at the end of this post, both of which were very freshly scaled and alive when found) and little or no other work for a period of years, even when there are signs of infestation by multiple insect species (based on the presence of exit tunnels that vary greatly in size and shape). I’ve included multiple examples, long shots and details, to illustrate.
On the 20th, Patricia, Steve, Phil, and I went to Sector 2 together. We went through the area where I recorded calls in 2013 and where we found concentrations of scaling in spring 2012 and during the 2012-13 season. There has been none since in this little patch. We found no recent looking bark scaling in the morning (as it turned out, we missed a group of three sweet gums with high branch work perhaps a quarter mile to the northeast of this area, see below.) One odd highlight was coming across a patch of forest floor with many of these beautiful ice formations that had formed around the stems of a couple of species of plant.
At a little before noon, Steve opted to turn back; we had already covered 2.3 miles. Before we went our separate ways, we all speculated on and were baffled as to what might have damaged this sweet gum. The wounds seem to have been caused by a scrape, but there were no downed trees or tops anywhere in the immediate vicinity.
Phil, Patricia, and I proceeded another half mile farther north, reaching a hickory stub that I found in the spring of 2013, shown below. The stub was still standing, and the areas with putative ivorybill work had lost more bark but showed no signs of further woodpecker activity. The presence of a click beetle in this 2013 photo suggests that parts of the tree were already starting to rot even then.
We found two sweet gums with extensive scaling on large branches within 30 yards of this snag. Some of the work was recent. This is something that we’re finding repeatedly; even within clusters, the interesting feeding sign often seems to appear in tighter groupings involving two or more trees. I’ll provide a possible explanation in my next post.
We found a particularly unusual bark chip at the base of the tree on the left. While it comes from a relatively small branch, the way it was removed may be significant. Over 1/3 of the chip is cylindrical encompassing almost the entire circumference of the limb; it was not pecked off piece by piece; instead, it appears to have been loosened by several blows and then pried free. The bark is hard, suggesting it was tightly attached; it was moist and contained a good deal of frass when found. The piece is very large, approximately 13″ long and nearly 7″ in circumference.
On the return trip, we found a small group of three sweet gum snags, somewhat on the longer dead side. All three had recent to fresh scaling, and there were very large bark slabs at the bases of two of them. These slabs of bark were dense and hard, suggesting that they were tightly adhering when stripped.
We came across a massive relict cypress on the way back. It’s not the first time I’ve seen this tree, but it never fails to take my breath away.
On the morning of December 21st, Phil and I went to Sector 1, and Patricia and Steve went to Sector 3. We decided not to deploy a camera on the downed top we had found on the 16th. We have two functioning cameras at the moment, and it seemed more prudent to deploy them on untouched substrates. We didn’t find any new scaling or a substitute target, so we decided to head for Sector 3 where I had a couple of targets in mind.
As we were walking to the car, I got a text from Patricia saying that she and Steve had just had a possible auditory encounter. Steve is a dedicated birder with very good hearing and excellent ear-birding skills. Patricia has limited experience, but she is a retired opera singer with a good general ear. Here are their descriptions of the morning’s events.
Steve: At about 9:10 am, Patricia and I were in the bottomland hardwood area in Sector 3. The weather was overcast and cold without any wind – very good conditions to hear bird calls. We had walked southward for about a quarter of a mile in the bottomland area when we had decided to do some DKs. Actually it was Patricia’s idea to do some DKs, and we proceeded to find a small American Holly that was the right size to cut two sticks for knocking.
Patricia: I thought it would be a good location, as I remembered Frank, Steve, Mark and I had done them at the same location a few years back. I remember the fallen tree we all sat on for lunch. Steve had sardines! And where Frank sat down at the base of a tree and started to snore. When I mentioned to Mark that Frank was sleeping, Frank retorted “I’m not asleep”
Steve: The location is one where we could see for a distance fairly well. When we started the DKs, we did not keep up with how many were done or how long we did them, but I think it was for about 10 minutes. We made an effort to keep watch for an incoming IBWO that would be responding to the DKs, but we were probably not as diligent as we could have been. At a point we had engaged in some conversation. I was sitting on a sweetgum log and Patricia standing about six feet away. My right side was facing south. Patricia was talking when all of a sudden I heard what sounded like at least two distinct calls from my right. The calls sounded like textbook calls of the IBWO – a bit like a toy horn was being blown. I know White-breasted and Red-breasted Nuthatch calls very well and what I heard did not sound like either of those birds. I immediately put up my left hand to stop Patricia from talking and pointed with my right hand toward the south. I told her what I had heard while we both strained to hear any more calls. There were no more calls. Also, we did not see the bird. It is highly likely that we did not spend enough time watching and listening for the bird after I had heard it call. It is hard to say how close the bird might have been to our location because I don’t know how far their call can be heard.
Patricia: I think I did about 10 DKs, perhaps 15-30 seconds apart. When I didn’t hear anything interesting,I joined Steve, who was about 20 yards away. We started talking, and I was responding to something he said when his hands went up and his eyes widened. He whispered, “Did you hear that? Kent calls?” I shook my head no. We listened for a while, but probably no longer than 5 minutes.
Steve suggested we do another round of DKs to see if we could call in whatever made the sound again. I asked him to do the next round, as I my hands were stinging and sore; plus I wanted to hear them from someone with more experience. I think that, should someone have an auditory encounter, another person should take their place during a second round of DKs.
I stayed where I was standing when Steve heard the kents but was facing directly south. After 3 or 4 DKs, I heard something similar in cadence, but it had a sharper, crisper quality to it (similar to recorded Campephilus double knocks). It came roughly from the southwest. By the time Steve joined me later, I had convinced myself that it was caused by the logging that we heard going on in the distance, also to the southwest. If I mentioned hearing the DK to Steve, I probably downplayed it, blaming the logging or a falling limb; the winds were very calm at the time, and I didn’t hear any similar sounds from the logging that morning.
I have not spent much time in the field and am reluctant to place too much weight on my observations. I’d much prefer the IBWO (should it be out there) land on my shoulder “Sonny Boy” style and leave behind a fine DNA sample, after I manage to take a series of selfies!
Don’t we all . . . or at least that we could call them in like Barred Owls.
We met up with Patricia and Steve, and Phil set up the cams; one is currently aimed at a sweet gum stub we targeted last year before losing a camera to flooding. There is some fresh woodpecker work, I suspect Hairy, on the stub, so this may be a good time to target it. The other cam is trained on both a downed sweet gum top and a longer dead snag. Both are within the area where we’ve had multiple possible encounters recently, not far from the heavy concentration of sign found last spring.
Toward the end of the day, Phil went to do an evening stakeout in sector 1; Patricia went with him, while I took Steve a little farther north to show him a couple of the hickory stubs. In this location as well, there were a couple of recently scaled sweet gums in within 20-30 yards of the older hickories, which were similarly about 20-30 yards apart. We also examined one of the hickories Steve photographed in 2013; it was alive at the time. This one had decayed somewhat more rapidly than many of the others I’ve found, but it’s at a lower elevation relative to the nearest water body.
Steve remarked that he’s never seen feeding sign like this anywhere else, and he has spent countless professional hours in bottomland hardwood forests.
Frank, Phil, and John Williams will be in the search area over the next few days, so there may be another report coming soon, in addition to the post I’m planning on hickories and foraging behavior.