To expand on some of the data included toward the end of the March trip report (which is worth reading in in conjunction with this post), I thought it would be informative to provide a season by season and sector by sector breakdown of the scaling I and others involved with Project Coyote have found since the spring of 2012. To do so, I’ve gone through my notes and photographs and have done my best to reconstruct the data collected. While not complete (I’m quite sure a good deal more scaling was found in Sector 3 during 2013-2014, for example), I think this breakdown is a fairly accurate reflection of what we’ve found over the years.
As discussed in previous posts, I think extensive scaling on hickory boles is the most compelling for Ivory-billed Woodpecker. Bark on this species is thick, dense, and usually remains very tight for a long time. Extensive scaling on sweet gum boles and oaks (upper boles and large branches) is second among work that I’ve found. Work on small boles, and higher and smaller branches is somewhat less compelling and is more significant for its abundance. Some of the high branch scaling and work on smaller boled sweet gums may well have been done by Pileated Woodpeckers (and possibly by Hairy Woodpeckers), but the abundance, the presence of large bark chips in many cases, the way it appears in clusters, and the fact that Pileateds scale infrequently suggest a different source for much of it.
I have excluded all work where squirrels are suspected but have counted one tree, a hickory found this year, on which the work could well have been that of a Hairy Woodpecker. Hairies do forage for Cerambycid beetles just under the bark, but they’re only capable of removing tight bark in small pieces; their work on hickories is perhaps more accurately described as excavation through the bark.
The trail cam images toward the end of this post are the best we have (out of many thousands of hours of coverage) showing how these species forage on suspected ivorybill feeding trees.
All trees were live or recently dead (twigs and sometimes leaves attached). All scaling was on live or recently dead wood.
Sweet Gum (Liquidambar styracifula)
Sector 1: 46
Sector 2: 8
Sector 3: 51
~15% had scaling on boles (a few of these were large trees). The majority of work was on crowns, including larger branches. Fallen trees were included when woodpecker involvement was evident and bark was tight.
Bitternut Hickory (Carya cordiformis)
Sector 1: 3
Sector 2: 4
Sector 3: 7
All trees were standing; scaling was on boles and was very extensive (the tree shown on the homepage is one example) with one exception from this year . Insect tunnels were visible in all examples. An additional hickory with a modest amount of high branch scaling was found in Sector 1 this year but was not counted for this analysis.
Oak (Quercus) spp.
Sector 1: 1
Sector 2: 4
Sector 3: 0
All oaks had scaling on large branches; one also had some on the bole. All oaks in Sector 2 were found in a single cluster.
We have some information on forest composition in Sector 3, and it appears that sweet gums make up approximately 19%, oaks upwards of 35%, and hickories somewhere under 10%. Sectors 1 and 2 may differ and be more varied in overall composition.
The overwhelming preference for sweet gums relative to their abundance stands out. The scaled oaks are a mix of species, one Nuttall’s, one willow, the others unidentified.
In Sector 3, I am treating the compact stretch from the location of Frank Wiley’s sighting last spring/downed sweet gum top where we had the camera trap to just south of our current deployment as a cluster. The estimate of 23 trees being found in this area is conservative. I have only found one instance of recent scaling north of the location of the downed limb/Frank’s 2015 sighting. The main cluster has been in the same vicinity this year and last, with additional work scattered around farther south. Two of the hickories are within 30 yards of each other, approximately half a mile from the cluster, and one was on the edge of the concentration.
It also may be significant to note that we found a cluster of old but intriguing cavities in the same vicinity as the Sector 3 concentration in 2013-2014. Most of these seem to have fallen. The difficulty we’re having finding active, suggestive cavities is vexing, and may be the most compelling reason to be skeptical about the presence of ivorybills in the area. At the same time, finding Pileated cavities is difficult, even in defended home ranges.
I’m treating Sector 1 as a single concentration; the vast majority of the work is on a natural levee where sweet gums are abundant. The entire area is considerably larger than the other clusters, but given the abundance and ease with which we’ve found sign there over the last five seasons, I think it constitutes one area of concentration.
In Sector 2, there was a small cluster in the area where I recorded putative kent calls in 2013, with work found in 2012 (spring and fall) and 2013. Because the area is small with open sight lines, I can be confident there has been no recent work there since late in 2013 (I last passed through it with Tom Foti back in March of this year.)
The sweet gum work Tom and I found on that day was perhaps half a mile north of this cluster, within 100 yards of the hickory on the homepage. The other hickories found in the 2013 and 2014 seasons were not far away, no more than 500 yards apart as the crow flies.
There’s obviously some bias here, since there’s a relationship between finding feeding sign in a given area and spending time there. Nevertheless, I have little doubt that the putative ivorybill work tends to be clustered. I also have little doubt about the strong preference for sweet gums, since I’m not looking at tree species when I look for scaling. The degree to which sweet gums are favored has only become clear over the last year or so.
Frank pointed out this data does not reflect most of the scaling that likely exists in relatively close proximity to the Sector 3 cluster but cannot be quantified because it is in an area we have intermittently visited due to inaccessibility. Only two or three examples are from this area, which has been visited a handful of times.
As usual, much of this report will be focused on bark scaling. I found an unprecedented amount of fresh work this trip, a total of 29 trees, all sweet gums. I only counted live and freshly dead trees that appeared to have been scaled within the last year, and probably more recently than that, in most cases. As will be discussed, I was able to ascertain that 11 of these trees had been worked on no earlier than March 15th. I was selective about what I included in the count, relying on my years of experience looking at scaling and how its appearance changes over time and this passage from Tanner for the criteria:
Ivory bill sign shows as bare places on recently dead limbs and trees, where bark has been scaled off clean and to a considerable extent. Pileateds do some scaling too, but it is usually confined to smaller limbs and those longer dead. Freshness of the sign can be judged by any appearance of weathering, which will soon turn bare wood a grayish color. Extensive scaling of the bark from a tree which has died so recently that the bark is still tight, with a brownish or reddish color to the exposed wood showing that the work is fresh, is one good indication of the presence of ivorybills.
We had a number of visitors during my stay. Tom Foti joined me again on Tuesday and Wednesday, and Phil and Eric Vanbergen came along on Friday. I appreciate the Vanbergens’ help in collecting the data I’ll be discussing. It’s great to have such enthusiastic young people involved. Meanwhile, John Williams (Motiheal from ibwo.net) visited and spent four days in the field with Frank. Both John and Frank are planning to provide their own accounts, and those will be posted in the weeks ahead.
A general note about the week, leaf out progressed rapidly, and the change between Sunday the 20th and Saturday the 26th was dramatic. Nonetheless, I was able to find a good deal of feeding sign later in the week.
I arrived on the evening of Saturday, March 19th, and Frank and I spent the 20th in the northern sector. There had been severe flooding in the area earlier in the week; the waters had receded – we suspect by the 15th or 16th and certainly no earlier than the 15th. One of our trail cams, placed about 4’ above the ground, was completely overtopped, ruining the card and probably the camera as well. Such floods are exceedingly rare, perhaps a once in 500 year occurrence in the area. Fortunately, flooding tends to recede rapidly, but crossing both permanent and seasonal water bodies remained a much bigger challenge due to deep water and slick banks. The most stunning aspect of the flooding was the near total scouring of leaf litter in many parts of the search area, leaving bare soil and deposited silt visible. The landscape was transformed, and familiar spots looked radically different.
Frank often describes walking through the forest on dry leaf litter as “walking on cornflakes.” The absence of leaf litter limits the noise made by walking. This may be advantageous between now and late fall. Unfortunately, I anticipate being able to visit the area only once more before summer, probably in June.
The flooding had another benefit this trip. The absence of leaf litter makes it much easier to find fresh bark chips on the ground and to determine with some degree of certainty when scaling has taken place. The flood waters receded no earlier than March 15, so all fresh chips found below trees where the leaf litter had been scoured were no more than a week old.
When we reached the vicinity of the downed top, first discussed here, we heard a loud single knock. Frank’s initial reaction was that it might have been a gunshot, but we both agreed that the sound seemed to have come from a nearby source; we heard no other shots that day and saw only one vehicle, almost 2 miles away. Later in the morning we heard a couple of weak possible double knocks and later a very good sounding one.
We also found a little bit of scaling just north of the northern concentration discussed below. While some of it looked to be quite fresh, we did not find any bark chips.
The scaling in the first of the above photographs is somewhat marginal, as only a single smaller upper limb is involved. While I’m unsure, I don’t think I counted either of these trees, as I only started keeping track later in the week; both examples came from very close to the northern cluster discussed below.
I was on alone on the 20th, and I returned to the same area. I found a good deal more scaling.
In many cases, the scaling shows sign of progressing from treetops down, as Tanner described.
The detail of the small tree, scaled down to where small branches are still in leaf, is at the edge of a small pond around or in which I found five other trees with recent scaling on them, as well as two more with older work (not counted).
There was new work on one of the trees I found last month, the larger one in the background, below. I found several other scaled trees in the immediate vicinity, including the one in the foreground, on which we’ve now deployed a camera, and much of that work was fresh too. I chose a spot for a stakeout and spent about an hour watching the treetops in this area of concentrated work. This location is 140 yards south of the small pond described above and is at the southern boundary of the cluster. During the stakeout, I heard a loud single knock that seemed to have come from the vicinity of the small pond.
As I was leaving, I passed the pond again and found what appeared to be new scaling on one of the trees at its edge. There were fresh chips in floating in the water at the base.
Tom Foti arrived on the morning of the 22nd. We spent the day in the one of the southern areas where we’ve found concentrations of bark scaling in past years and where there have been both possible visual and auditory encounters. We found several scaled trees in this area but did not see or hear anything.
I met up with Tom on the morning of the 23rd; I had decided overnight to be more methodical in my approach to documenting scaling. I’ve been so focused on what might be diagnostic that I haven’t attempted to quantify what I’ve found thus far and haven’t kept detailed location information. Thus, it seems like a good idea to start keeping better track. This should prove useful if we can document that ivorybills are present and that they are responsible for the bark removal.
Tom and I heard 6-8 likely kents at ~9:00 am, this at the downed top where we had the camera, the same location where Frank had his sighting last spring. The calls came from three directions, south, east, and west.
We headed south and met up with Frank and John in the core of the northern concentration, south of the pond. We did an extended playback series; John will have more to say about the specifics in his post. We all heard a nearby double knock during the playback; Tom, John, and I were sitting close together near the speaker and thought it was a single, but Frank, who was positioned closer to the source of the natural sound, called it as a double.
We found some very fresh bark chips (moist with sap) at the base of a 12” DBH dying sweet gum that has areas of scaling high on the bole. The tree (which is shown above) is only a few meters from the one found last month. We’ve deployed a camera aimed at this bole. Given the quantity of activity in the area and the evidence of return visits to feeding trees, we hope to get some hits before long.
We removed a piece of bark from a looser spot on a nearby downed tree (which had been fed on by woodpeckers both before and after it fell). Beneath the bark were Cerambycid larvae, pupae that I also suspect are also Cerambycids, and what I think may be a very young Elaterid larva. We placed some of these larvae and pupae on the piece of bark to illustrate. We suspect that Allen did the same for what became Plate 10 in Tanner.
On the way out and not far from the cluster, I spotted what appears to be the start of a large, irregularly shaped cavity. We’ll monitor this and see whether there’s any further excavation.
It rained heavily on the morning of the 24th. I spent part of the afternoon trying to take measurements but didn’t have much success, since I was using an ordinary tape measure.
On the 25th, Phil and Eric Vanbergen joined me and we took measurements in the two areas where there are concentrations of scaling, finding several more trees in the process. When I got back to Frank’s, the forester’s DBH measuring tape I ordered had arrived, making it possible for me to take measurements on my own.
I spent the 26th measuring suspected feeding trees in the southern area and found several more with recent work on them.
Except for feeding sign, I did not see or hear anything suggestive of ivorybills during my last three days in the area.
Now I’ll turn to some of the data I collected this week.
I counted 29 suspected recent feeding trees in the two areas, 13 in the northern sector and 16 in the southern. I did not count work that appeared to be more than a year old or work that was limited to very small branches.
The areas are 2.05 miles apart. The northern area was logged (probably partially) in 1905, although there may have been some later selective cutting. The southern area was logged in 1935. Forest composition is somewhat different between the two areas, with sweet gums seeming to be less predominant in the southern one. In the southern area, the scaled trees are in a narrow, almost linear strip with an area of .13 square miles/83.2 acres/33.67 hectares. The northern cluster is more compact and polygonal, with a total area of .03 square miles/19.2 acres/7.7 hectares. Within both areas, scaled trees were often found in groups of 2-6 – 11 out of 13 trees in the northern area and 11 out 16 in the southern. (This includes the cluster in and around the pond, which is perhaps 30 meters in diameter, but otherwise applies to trees that I estimated to be 20 meters apart or less.)
Scaled trees ranged from 6.5” dbh to over 5’ (estimated) for a gum with a split trunk, one stem live and the other dead. All but 3 inaccessible trees were measured.
76% of the trees were alive, sometimes just barely, with scaling on dead or nearly dead limbs or boles. There was scaling on live parts of one or possibly two of the trees.
Though we have found scaling on boles of larger trees in the past, all trees scaled on boles were 12” DBH or less. While these measurements may not be meaningful absent a random sampling of trees in each sector for comparison, I thought the numbers might be of some interest even now, especially in light of the recent discussion of Tanner:
This is obviously a very small sample, but I think it’s interesting nonetheless. The three smallest trees in the northern sector were all in or near a pond that appears to have had its outflow blocked in recent years. They probably died due to the change in hydrology. But for that difference, there seems to be an even greater favoring of 25-36” DBH trees than found by Tanner, and this is so even in the less mature southern sector (again without data on overall composition). This year, feeding sign has been found exclusively on sweet gums. We’ve found a few scaled oaks over the years and more bitternut hickories; I suspect the latter are being fed upon at a high rate relative to abundance. We’ve discussed doing some random sampling for tree size and species, but given our limited resources, this may not be worthwhile or feasible at present.
Of course, none of this proves that ivorybills are in our area, but I think it’s another indication that they are. The best-case scenario is that the dramatic increase in scaling this year and in this season is related to there being young in a nest or nests.
Part 1 is here.
Thursday the 26th was Thanksgiving, and Frank spent the morning cooking. I ventured out alone; I get less comfortable going solo every year. Because I’m not very good with a GPS, I tend to prefer visiting areas I know well or restricting myself to places where I can rely on my sense of direction, compass, and iPhone map to get out safely.
For these reasons, I returned to the area where we had concentrations of scaling in 2012 and 2013, and where I recorded calls and had a possible sighting in 2013. There has been a significant increase in human and porcine activity in this area; both people and hogs are having an impact on the hydrology, and places I know well have changed a lot in less than three years.
I did not see or hear anything of interest – no sign, no calls, no knocks, but this is where access to the bottom is easy. The damage is being done on the periphery, and the core is much harder to reach. (Much of the activity in 2012 and 2013 was remarkably close to the edge.) Most of our attention has been focused elsewhere since 2014, so there’s no telling what might be going on in less accessible parts of this sector.
November 27th was something of a banner day but also a very difficult one. Frank, Brian, and I got to an area that hadn’t been visited before, although we did cross a track that Frank and Bob Ford made back in October. Access to the bottom involves hiking approximately 2 miles, .5 of which is on an old logging road. The rest is cross country and is not easy going, since there are dense pine plantations to traverse. Beyond the pines, there are several sloughs to cross or circumvent, but once you get there, it’s an incredibly beautiful area.
As Mark says, the area is quite beautiful once one has made it into the core. The difficulty in reaching the “core” cannot be overstated. The portion of the hike on the old logging road (actually more of an overgrown trail) is not too difficult, but once committed to crossing terrain, it becomes an entirely different story. We have often remarked on this, but I believe a little more explanation of exactly why the going is so tough will help the reader to better grasp the challenges.
Once the trail is left behind, one has to decide whether to blaze a straight line, or allow the terrain to dictate the direction of travel and work in a general direction. We generally just plow through thicker, younger pines in a straight line. The buffer habitat, which runs to middle aged pine with some oak and hickory scattered about is not too bad for either choice – at first glance. Once into these areas, one finds a lot of blown down timber in various stages of decay, from very recent to several years old. Even on level ground, these blowdowns require going off course, or stepping over. Then there is the occasional blackberry or saw briar patch to contend with.
As one continues to approach the core, the sloughs that Mark mentioned in passing begin to impose obstacles. Many times, to maintain a straight course, we find ourselves crossing the same slough several times. The sloughs are of two types, each presenting a different set of challenges. The first are the tributary sloughs. These are often dry, but are incised into the surrounding terrain, requiring one to find a way into and out of the streambed. The depth of the incision varies from a couple of feet to as much as ten to twelve feet depending on the carrying capacity of the slough, and its proximity to the main stream channel. The second type are the larger cutoff, stillwater sloughs. Once the rains begin in October, these hold water all the time. While only incised a foot or two into the terrain, they can be a couple of feet deep, often just enough to overtop one’s boots. This requires leaving the course line and hunting a place that’s shallow enough to cross – or finding a log to cross on. Waders, except during the wettest, coldest times, are not really practical as they get very hot and uncomfortable on even slightly warm days. Another challenge is the uniformity of the various types of habitat. Without a compass or GPS (I use a very high end Lowrance unit and carry a high quality compass for backup) one can be seduced by the easier walking and just make big circles, not really covering much ground. I’ve lived near, and turkey and deer hunted in this area for much of my life, and a few lucky souls get to spend a night or two in the woods every year.
On this particular day, Friday the 27th, the understory in the portion of the core area we visited was quite thick, unusual in this bottom, where the core areas tend toward an open hardwood gallery forest. The area is just a bit higher in elevation than most of the rest of the core – perfect for native bamboo canebrake. The cane affords a bit of protection for the blackberry briars and other “catchy” vegetation, making traversing even the heart of the bottom in this particular area a difficult proposition. On our way out, we encountered one of the “stillwater” sloughs that I mentioned earlier. Brian and Mark got water in their boots crossing it. I found a downed loblolly that made a pretty good bridge, but the bark was long gone, and the log was unbelievably slippery. I “scooted” across rather than risk a dunking, and strained my wrist in the process. Maybe I should have opted for the wet feet…
At the farthest point from the road, we found a recently downed sweet gum top that had been fairly heavily scaled (more heavily than the similar tree we found on the 24th).
The hanging, shredded bits of cambium on some of the scaled areas appear to be what Edith Kuhn Whitehead said her father considered diagnostic ivorybill sign. This led me to revisit Tanner and look at Plate 8; the images of feeding sign in Tanner are very poorly reproduced, and the originals are not much better. There is a higher quality scan of Plate 8 on the US Fish and Wildlife Service’s website, and after another look, we’re struck by the similarities between that image and a couple of the above details. While Tanner is often opaque about his reasons for selecting images of feeding sign, we suspect Plate 8 was included to illustrate what Mrs. Whitehead described.
We spent over an hour in this location and heard multiple possible kent calls and double knocks. We captured one of the double knocks on Frank’s recorder, but it’s too faint to be analyzable. One of the calls that I heard (but Frank did not) was perhaps the most Singer Tract-like ever to my ears, so much so that I had to ask Frank whether he had done a playback.
On the way out, I spotted some more extensive high branch scaling, apparently on a sweet gum within 25 yards of the downed tree.
Unfortunately, while the location is fairly close to the concentration described on the blog, it’s only reachable as the bird flies. We’d love to put a camera on it, but that’s not possible at this time. And all four cams are deployed in promising locations. We don’t have the time or personnel to handle more than we’ve got.
On Saturday the 28th, we retrieved the card from the camera that’s trained on the downed sweet gum top. It functioned perfectly but produced no hits. We did get some apparent double knocks after a series of ADKs; one was captured on the recorder but again was too faint to be analyzable.
We’d like to address a Facebook comment from a British ornithologist and extinction believer who characterized our inability to obtain something conclusive thus far as “negative evidence”. The fact of the matter is that the negative evidence we’ve obtained relates to Pileated Woodpeckers, not ivorybills.
Pileateds are abundant throughout the area, in the uplands as well as the bottoms. I constantly scan the woods for suggestive scaling. To repeat something I’ve said in a couple of earlier posts, we have seen an abundance the type of work we think is characteristic of ivorybills in our two Louisiana search areas. I have looked at Pileated sign throughout much of that species’ range and have examined countless images of Pileated Woodpecker scaling online. I have not found any examples that match what we take to be ivorybill work. Nor have I ever found any in our search area’s mixed pine-hardwood uplands. In the bottomlands, we’ve found this work scattered throughout the mature forest. We’ve also found clusters of it in several locations. In a couple of places, like the area I visited on Thursday, there have been concentrations of scaling in one or two years and not in others.
This week we got a series of images of a PIWO on both forks of the downed sweet gum top (not retained), where it spent several minutes. It did no scaling. Over the years, we have obtained a few sequences showing the same behavior, including this one. In a single instance, we captured a Pileated scaling a quarter-sized piece of bark, with some difficulty, from our target tree, a freshly dead oak. It did nothing more, and approximately six months elapsed between incidents of major scaling. (The second round happened after we’d removed the trail cam.)
There’s no way to prove a negative, but the evidence we’ve obtained points to something other than Pileated Woodpeckers as the source for the following reasons:
- The scaling is unlike work done by Pileateds elsewhere.
- We have documented Pileateds on heavily scaled trees but have not documented them removing anything but a single small piece of bark.
- The distribution of the scaling in our search area points to something other than Pileated Woodpeckers as the source, since Pileateds are abundant throughout, and the scaling is found only in mature bottomland hardwood areas, not in mixed and hardwood dominant uplands.
- The fact that we’ve found concentrations of scaling in certain areas in one year and not in others suggests that whatever is doing the bulk of it has a home range that’s considerably larger than that of the Pileated Woodpecker.
- Anatomically, bark scaling is an inefficient foraging strategy for Pileated Woodpeckers. It seems unlikely that Pileated Woodpeckers would do so much foraging in such an inefficient manner when other food sources, including insects in rotten wood and (at this time of year) mast, are abundant.
We hope the current camera deployments will solve this mystery of what’s doing this type of work . . . within the next few weeks.
I’ll be posting Frank Wiley’s report on his recent visit to the Project Coyote Search Area in two parts. Below is his account of his first day in the field.
I was contacted last month by Bob Ford, a biologist with the USFWS in Tennessee, about a possible visit to the Project Coyote study area sometime in early October. After some back and forth, we agreed that the weekend of the 9th would be best for both of us. Bob has visited the area in an unofficial capacity on a couple of previous occasions; he is a skilled birder, with a Master’s Degree in Wildlife Science. His focus has always been on birds and bird-habitat relations, especially in bottomland hardwood environments. All that aside, Bob is a great guy to spend time with, and an all-around skilled woodsman. He arrived on the evening of the 8th, having spent the earlier part of the week fishing in South Louisiana with some of his colleagues with the USFWS.
October 9, 2015:
We arrived at the study area at dawn, shouldered our packs and entered the forest. This particular spot is in the northern sector, and provides the easiest access to the area that we informally call Jurassic Park from a road that passes through the surrounding uplands – thus cutting out over a mile of fairly difficult foot travel at the beginning and end of the day. We were barely out of sight of the truck when I heard a rapid ticking sound in the leaf litter near my feet. I thumped the ground with my walking stick and was rewarded when a Copperhead about 18” long moved due to the vibration. Only a moment before, it had been completely invisible, camouflaged by the surrounding leaf litter. We stopped for a few moments, took a few photos and left the little guy to go about his business.
We hiked a fairly difficult three quarters of a mile through the bottom, crossing several deeply incised sloughs and secondary creek channels. The area was extremely dry; there’s not been a significant rain event since early July, when a series of severe thunderstorms passed through. Stealth was impossible, the dry leaf litter making it sound like we were walking on Corn Flakes. We made it to the main channel, and walked beside it until I found the top of a sweet gum tree that had blown down during Mark Michaels’ last visit. (It had green leaves and no sign of insect infestation when it fell in April.) We had speculated that there was at least a decent chance that ambrosia beetles would infest the two main forks of this top over the summer, and hopefully attract large woodpeckers. The smaller of the two forks did not disappoint. Not only had it been infested with beetles and larvae, the bark had been stripped from 60% or more of the branch. The scaling, in all respects fit the very narrow set of parameters that Mark and I have come to believe can be considered diagnostic as the work of an Ivory-billed Woodpecker – that is, extensive scaling on a freshly dead/dying tree with very tight bark, large (silver dollar or larger sized) bark chips that have clearly been removed with one or more powerful strikes, and little or no damage to the underlying sapwood.
When Mark first spotted this top on April 21, we both felt it was important to get a camera to this location to watch for woodpeckers. With this in mind, I had brought one of our new “Plotwatcher Pro” HD time lapse video cameras with me. I found a nearby tree that gives the camera a nearly perfect angle for recording any succeeding visits to this downed top by a woodpecker – both the stripped part, and the part that is almost untouched. We have high hopes for this camera in this location. It will take a photo every 5 seconds from 6 AM to 7 PM every day for three months or more according to the manufacturer.
While we were stopped, we took the opportunity to perform an ADK series and run a couple of playback sequences. During the quiet period, we neither heard nor saw anything suggestive of IBWO, even though there was a lot of activity from other woodpecker species.
As the main stream through the bottom is at a lower level than I have ever seen it, we took full advantage of the opportunity, and crossed at a location where the banks were eroded in such a way as to allow us to get in and out. Remember that the stream bed is incised approximately 15′ into the surrounding ground, so one has to be careful in choosing a crossing point, even with the stream completely dry in places. We did an “M” shaped transect that involved about 3 miles of difficult to negotiate terrain. The dry sloughs and incised cutoff channels are much more common in this area, making traversing the terrain much more difficult. We stopped at lunchtime and at two o’clock performed ADK series and playbacks but heard nothing suggestive of ivorybill activity.
At one point, I was walking near a large tree, paying more attention to the canopy than where I was putting my feet, when I happened to glance down. I quickly hopped to the side, because my left foot was about 3″ from the head of an enormous Canebrake Rattlesnake (Crotalus horridus atricaudatus). Bob backpedaled about 5 quick steps and asked, “Where’s it at?” Like me, he was very impressed with the size and apparent health of this beautiful and potentially deadly predator. Bob later said that he reacted the way he did because, “If it was big enough to startle you, I didn’t want to get too close…” We took a number of photos while the big guy (we estimated his length at nearly 5′) lay placidly with his head on a root buttress, clearly waiting on a convenient squirrel to pass within striking distance. He seemed totally unconcerned with our presence as we circled him (I got quite close several times) making photos. Finally, I just couldn’t resist and asked Bob if he wanted to hear him buzz. I gently poked him with my walking stick a few times. After the third poke, he rattled a bit, and coiled into the “OK, I’m pissed, now leave me alone” position. For those who’ve been dying to know, the answer is, “Five, and a button…”
We exchanged a happy high–five at having encountered this big guy and continued going about our business, leaving him to go about his. Truly an awesome and exciting encounter.
As the day wound down, we worked our way back to the stream, having explored about two and a half to three miles of ground that no one associated with Project Coyote had explored previously. The forest is of outstanding quality with many superdominant trees, mostly sweet gum and Nuttall’s Oak indicating a mature, healthy, and beautiful swamp forest. We crossed, and made our way back to the truck, feeling good about a productive and enjoyable day in the field.
As I mentioned earlier, Bob had spent the first part of the week with some of his USFWS colleagues fishing in south Louisiana. They were successful in bringing home some Redfish and Speckled Trout, both game fish that are exceptionally tasty. When we got in, we cleaned up, and I fried up a good mess of both kinds, along with steak fries and hush puppies. Bob liked my fry mix so much that he brought two ziploc baggies of it home with him for future use. I can make more. Got to teach them folks from up north how to cook!
Mark here pointing out that Bob’s from Tennessee, hardly up north from where I sit. Stay tuned for Part 2.
Jamie Hill, who has worked with the Cornell and Auburn teams, recently posted a Facebook link to a very interesting article from the September 2014 issue of Smithsonian. Ivory-billed Woodpecker aside, the piece is well worth reading, but for the purposes of this blog, the article got me thinking about reasons for the ivorybill’s decline and the possible role of the longleaf pine. These ideas are not entirely new or original with me; Lester Short went even further, suggesting that pine might have been the ivorybill’s primary habitat; Jerome Jackson devoted several pages of In Search of the Ivory-billed Woodpecker to pines, and Fangsheath of the ivorybill researchers forum has hinted at this too.
I was struck by just how congruent the historic range of the ivorybill is with the range of the longleaf pine (Pinus pilastrus). The overlap is not exact, and the pre-Columbian range of the ivorybill extended as far north as Ohio. Nonetheless, conditions in the Singer Tract were objectively quite different from what they were in many other parts of the historic range.
A recent blog post on the Tallahassee Democrat site reiterates the conventional wisdom about the species and the reasons for its decline. Author Budd Titlow writes: “Before the Civil War, when much of the southeastern U.S. was covered with vast tracts of primeval hardwood swampland, ivory-billed woodpeckers ranged from North Carolina south to Florida, west to Arkansas and Texas, and north into Oklahoma and Missouri. Then, after the Civil War, extensive logging of these old-growth swamps wiped out most of the ivory-billed’s habitat in one fell swoop.”
While there’s some truth to this history, it’s also a stereotype that’s based in large part on an imperfect reading of Tanner’s monograph and even more on Tanner’s dedication to protecting the Tract as the last remaining extensive old-growth stand in the southeast (although the Tract contained considerably less old growth than Tanner believed). Tanner’s efforts were admirable; the loss of countless acres of magnificent old-growth swamp forest was devastating environmentally and is unquestionably something to be mourned, but it seems unlikely that the destruction of these forests was the primary cause for the ivorybill’s decline.
The species was known to be disappearing by 1890 or even earlier, and Chester Reed’s 1906 Bird Guide to Land Birds East of the Rockies stated that the birds were restricted to isolated parts of Florida and possibly to “Indian Country” (Oklahoma). In The Travails of Two Woodpeckers, Noel Snyder, who attributes the decline primarily to hunting, points out that intensive logging of bottomland hardwoods began between 1890 and 1900. Logging of pine forests began considerably earlier, and these forests were severely fragmented, even before the Civil War. Snyder reads the early record (I think selectively) as indicating that ivorybills strongly preferred bottomland hardwoods and seldom used pines, in contrast to the Cuban ivorybill and the Imperial.
Jackson takes a different view, citing multiple references to the use of pines for feeding and nesting. Where Snyder reads Alexander Wilson’s early account as reflecting a preference for “swamps and bottomlands”, Jackson reads him as describing the preferred Carolina habitat as “a mosaic of baldcypress swamp and pine uplands, similar to the habitat in Florida”. Jackson goes on to suggest that, “It appears . . . that ivory-billed woodpeckers will inhabit both hardwood forests of river bottoms and pine forests of higher elevations, particularly old growth forests supporting healthy populations of beetles. They seemed to do best at the interface of these forest types, taking advantage of the resources of each.” (Emphasis added).
This meshes well with what Allen and Kellogg observed in Florida in 1924; the birds nested and roosted in cypress and were observed and photographed foraging in open pine forest. The Lambs’ limited observations in Cuba suggest something similar, a preference for roosting in pines but an equal division between pines and hardwoods for foraging.
Thus, it seems possible that the Singer Tract was actually suboptimal habitat for the ivorybill, since it contained no pine and little cypress. I’m also led to suspect that habitat fragmentation, rather than habitat loss may have been central to the decline of the ivorybill, with hunting as one of several other contributing factors. This fragmentation actually began well before the Civil War, but it accelerated with the post-war destruction of the longleaf pine forests, followed by the logging of the bottomlands. I’m personally convinced that the species beat the odds and survived, using one or both of the strategies discussed in this post. I wonder whether some of the modern search efforts have focused excessively on the bottomland hardwood model and not enough on areas where there’s an interface between forest types.
On a different note, I had planned to make my final trip to our search area for the season during this week and next. Water levels are very high right now, so I’ve decided to postpone until late July. Better to endure the heat and humidity than to be unable to move around in the woods.
As always, my time in our search area was very productive – inspiring new insights and ideas and producing suggestive but inconclusive evidence that Ivory-billed Woodpeckers are present in this location and have been for years. The weather was considerably more cooperative this trip than on the two or three preceding ones, although temperatures edged toward the uncomfortable – mid 80s and humid from Tuesday-Friday – and rain limited field time on Saturday and Sunday. I was alone from Tuesday-Thursday, and Frank Wiley joined me from Friday-Sunday. Later this week, I’ll post a day-to-day log that includes more about possible encounters and some additional images,
For reasons that should become clear, we are starting to think there may be a home range in an area of over four square miles (and possibly considerably more than that), much of which we have not yet explored, and some of which is very difficult to reach – a two mile walk from the nearest road and bisected by deep sloughs and streams. We have some reason to suspect that this range has been used for a number of years. This is in very mature bottomland forest, logged between 1905 and 1915, and it includes the stand of sweet gums where we found a cavity cluster last year.
Also on this trip, we did more experimenting with playbacks; I actually began the experiment shortly before I left for Louisiana, with a Pileated Woodpecker in my yard outside New York City. She responded with considerable agitation to my playback of Pileated calls and drums – calling and flying over at very close range while looking directly at me. She did not react at all to playback of ivorybill calls and pounding from the Singer Tract (the iBird Pro selections). Several species in our search area seem to react to ivorybill playbacks. Pileated, Red-bellied, and Red-headed Woodpeckers frequently react with drumming and scolding. In one instance, a calling Pileated Woodpecker went silent and flew away immediately after a playback. Barred Owls will often call immediately after, as will American Crows. In one case, a pair of crows came in to within 80 feet, apparently to investigate; in another, a Red-shouldered Hawk did the same.
There were three instances of possible ivorybill interaction with or response to playback. Two of them were very weak possibles, meriting only this passing mention. The third was a little more interesting and will be discussed in the day-by-day account. We will continue the experiment, both in Louisiana and New York (to see if and how various species react). We’ve recently been informed, by “Motiheal” from ibwo.net, that a Red-headed Woodpecker in Virginia approached in response to the playback of five kents.
One of the reasons we’re optimistic about having pinpointed a home range is the abundance of feeding sign in the area. In addition to the work sign from this area discussed in previous posts, there’s an abundance of older work, like this scaling on a hickory snag.
According to Tanner (p. 47), “Trees and limbs almost two years dead have lost almost all twigs, some small branches, and bark is loosened on some small branches.” Of course, the decay process is not as linear as Tanner’s description implies, and scaling of bark itself hastens the loosening of whatever remains. Thus, on scaled branches and boles, bark is likely to have loosened considerably unless the work is very fresh. Still, the presence of leaves and/or twigs is a strong indicator of recent death, perhaps even more so on blowdown, for which the decay process is likely hastened by proximity to the ground. In terms of more recent work, I found two sweet gums with sign on large high limbs, perhaps the most dramatic scaling that closely matches Tanner’s description we’ve found to date. Not only is it very extensive; the scaled limbs are quite recently dead. While it’s not possible to test the tightness of the bark, the presence of leaves in the case of the more recent scaling and twigs with buds in the case of the somewhat older work suggest that the limbs died within a six months to, at most, two years. It has been suggested that ivorybills are largely birds of the canopy that seldom if ever feed near the ground and that this behavior might account for the difficulty in obtaining clear photographs. Despite the fact that Allen and Kellogg observed a female bird feeding on the ground like a Flicker, and Tanner himself reported observations of foraging close to the ground, the idea that the species is limited to the canopy has become a kind of conventional wisdom. As I’ve discussed in previous posts, I don’t accept this notion and much of the feeding sign we’ve found has been low on standing trees and snags and on blowdown or slash. In the last trip report, I discussed feeding sign found on recently downed sweet gums (just outside of what we believe to be the hot zone, although possibly within it if it is larger than we currently suspect). On this trip, I found over two dozen examples of extensive bark scaling on downed sweet gum tops and limbs. This work was so commonplace that photographing additional examples seemed redundant. In all cases, the blowdowns were recent and involved very freshly dead wood. At least some leaves were still attached, making it likely that these limbs and tops had fallen in the last six months to one year. In the hot zone, I found only two sweet gum tops or large limbs that had not been scaled. Most of the scaling was recent to very fresh, probably one or two days old in one instance (unfortunately, it had rained the night before, so any scat had been washed away.) I do not believe that all of this is the work of ivorybills. Nonetheless, I suspect that much of it is, due to its abundance and extensiveness and in light of Tanner’s study and the preference he found in the Singer Tract ivorybills for recently dead and dying sweet gums (this even though I believe Tanner overstated this preference and did not sufficiently account for specific conditions in the Singer Tract).
I did not find this type of work in brief visits to areas outside the hot zone, where it was ubiquitous; nor have I seen anything quite like it elsewhere. I did not see anything like it on other species of downed trees; the only partial exception was some scaling on longer dead parts of a live downed hickory. As an aside, it’s worth mentioning that the species of hickory in our area were not present in the Singer Tract, although their congeners, pecans and water hickory were. Unlike Tanner, we’re finding scaling on hickories that likely exceeds their relative abundance. We’re also finding considerably less scaling on various oak species.
In addition to the work on freshly downed sweet gums, I found two standing, recently dead young sweet gums that had been worked on in unusual ways. Both showed signs of infestation by insects that bored into the heartwood. Both had been very heavily scaled, one with minimal excavation only around the insect tunnels. The other had been hacked up in a way that, in the words of several people, looked as if someone had taken a hatchet to it; the wood was hard and not at all punky. Whatever did this work chopped through a small branch to the point where it broke off and almost severed the top of the tree as well.
In his report on Cuban ivorybills, George Lamb described something similar:
Soon after we observed a female ivory-bill . . . feeding on the dead branch of a Hilacho tree (Torrubia obtusata) in a small stand of hardwoods. Suddenly the branch broke off while she was still perched on it . . . The Hilacho limb previously mentioned as breaking while being fed on, represents a type of feeding which was neither scaling nor digging. The limb was vertical and had probably originally been about three inches in diameter. Possibly it had once been scaled, but when recovered showed evidence of feeding to the extent that hardly anything was left. The wood was very punky and hand been chipped away from the perimeter to of the limb all along it’s 2 1/2 foot length. The chips, some of which we gathered, were long and splintery appearing, and were riddled with beetle larvae “tunnels”.
Our broken branch is approximately 2″ in diameter, while the top appears to be more than 3″. Unlike the Hilacho tree, the wood on this sweet gum was hard, not punky.
While I suspect that some of the work on these trees, the very targeted work on the limbs (small rectangular scaling/digging), may have been done by Hairy Woodpeckers, the bulk of it is extremely unusual, inconsistent with any Pileated Woodpecker work I’ve ever seen and with Tanner’s description of that species’ foraging preference for longer dead wood; the type of prey is consistent with what would be expected for ivorybills. While the work on ‘hatcheted’ sapling doesn’t meet the diagnostic criteria we’ve developed over the years, we think it highly likely that this is Ivory-billed Woodpecker work. The scaling on the other small sapling is generally consistent with our criteria, although it has some very limited excavation, clearly aimed at expanding existing tunnels, rather than digging into the wood in the manner typical of Pileated Woodpeckers. Again, from the Lamb report: At one point she was only about 25 feet away while she was feeding around the base of a small pine. She began working “barking” this tree around 30 inches from the ground and slowly worked her way up to the top.
Stay tuned for the second installment, which will also include details of a sighting Frank Wiley had on Friday, April 3.
Frank wrote this up and asked me to post it.
Recently, we’ve received several messages, and another blogger has mentioned the use of game cameras – also referred to as trail cams, or camera traps – as aids in searching for Ivory-billed Woodpeckers. We’ve been deploying trail cams since early 2009, and have had some intriguing “hits”. They have been useful in many ways, and we have learned a lot about the feeding habits of other woodpeckers – specifically, Pileated, Hairy, and Red-bellied – that were useful in giving Mark insights into the type of feeding sign that we have come to believe is most likely diagnostic for ivorybills. In dozens of deployments, and hundreds of hours of searching with boots on the ground, and sometimes in the water, we have NEVER observed a woodpecker performing the type of scaling that we have come to suspect is diagnostic.
While trail cams are a valuable tool in our arsenal, they are, by no means infallible. There are many pitfalls involved in their use. Firstly, they are not designed to capture birds – in fact many common species of birds are almost unidentifiable in the images. Birds do not set off the motion triggers that these cameras use, and why should they? The cameras are designed for use along trails and adjacent to food plots used by larger mammals – usually whitetail deer. I have tested the Reconyx “Hyperfire” cameras that we use, and even a large Wild Turkey at fairly close range will not trigger one, even at its most sensitive setting, while a relatively small (terrier size) dog will trigger one from a distance of twenty-five or more yards. The manufacturer has indicated to me that there is “something about the way birds reflect light in the visible and infrared spectrum” that makes the cameras’ triggering units unable to “see” them.
As a result, ivorybill hunters must find a camera that will operate in time lapse mode. For all their disadvantages (3.1 megapixels, low resolution among them) the Reconyx cameras offer the best time lapse mode available at an affordable price. This, in and of itself, though, becomes a handicap, as the card for each camera must be programmed, using a proprietary program provided by Reconyx, on a PC. One programs the card, inserts it into the camera, and hopes for the best – there is no way to check and see if the card/camera combination is functioning properly. This has led to many wasted deployments. Additionally, there is the problem of how often should the camera take a photo vs. storage capacity of the card. The cams are designed for 8 gig cards, sometimes they will function with a 16 gig card, but will universally malfunction with a 32 gig card. 8 gigs is usually enough for a ten-day deployment with the camera time constrained to take a photo every twenty seconds for ten hours a day – you do get to select the hours of operation though. While every twenty seconds would seem to be quite often (and a full 8 gig card will store upwards of thirty thousand images), perform a little test for yourself. Go out to your favorite birdwatching location and see how long a bird – any arboreal non-raptor species – stays in one location for twenty or more seconds. Captures of birds on game cams are a relatively rare event – I have looked at nearly a million Reconyx photographs and have picked up birds of any kind in perhaps a thousand images – identifiable birds in maybe two hundred.
The very first thing that has to be done when using game cams is to select a location where you suspect an ivorybill is likely to show up. This could be a tree with scaled bark and other indications that an ivorybill has visited it, or a cavity with features that seem to match photographs of known ivorybill cavities. Both of these are, at best, iffy propositions. One has to find the tree, geotag it (you do have a good GPS unit, right?) then return to the location – often several miles of hiking through some pretty rough and secluded forest, carrying the camera and its mounting system – which weighs around ten pounds. Then the camera and mount have to be positioned to get the target near the center of the frame, which gets easier with practice, and the camera and mount hidden and intervening vegetation trimmed so as not to interfere with the line-of-sight. Once all this has been done the camera can be turned on, armed, and left to do its thing.
Assuming that everything up to this point has been done perfectly, in ten days or so, it’s time to change cards, or retrieve the cam. Now one is faced with the daunting prospect of going through some thirty-thousand photos looking for anything “interesting”. Often, several days of images will pass without a single “hit” of any kind. It’s often a relief to spot even a small woodpecker or squirrel, to remind one that the target is part of a living ecosystem.
The series shown here is exceptional in terms of quantity of images, quality, and our ability to place the camera. (It may be significant for what it doesn’t show, a Pileated doing the type of scaling we think is diagnostic.) Even so, it was not possible to cover the entire target tree.
As I stated earlier, these cameras, within their limitations, are useful tools, but for my money, nothing really beats the good old MK I MOD I human eyeball. But at this point, that’s just not enough …
In addition to the suggestive photos we’ve already posted, we recently obtained some pictures at the site where last week’s double knock was recorded. Because we find some of these pictures intriguing but inconclusive, we have deployed two cameras in hopes that the double placement will yield an identifiable photograph. The first picture, taken under good lighting conditions, clearly shows a Red-headed Woodpecker (there is a roost at the very top of the snag); the others are ambiguous. We are posting them unedited and leave it to you to speculate about what they may be. We recognize that none of these are of anywhere near good enough quality to be identifiable as ivorybills, but we are doing some further analysis to get a clearer sense of scale. The camera placement is 85’ from the tree; the branches behind the tree are an additional 15” away. My preliminary estimate of the diameter of the tree just above the jug handle on the right is approximately 18”.
I have taken careful measurements using a camera with known lens settings and a rangefinder – when the weather is more congenial, I will make comparison shots at the exact measured ranges. This should give a margin of error of ~1″ or less.
Frank Wiley and I have spent the past four days in our search area, beginning on Thanksgiving morning. Before getting into the details, it merits noting that this weekend is the probably the peak of deer season in Louisiana. On Thanksgiving, there were perhaps fifteen or twenty people hunting on the edges of the habitat corridor. We encountered a single person in a tree stand that day, at the edge of the potential habitat. The number of hunters dwindled over the weekend, and on Sunday morning, we heard only one or two distant gunshots and saw a lone pickup truck parked along the parish road, nowhere near the bottomlands where we’re focused. On Thursday, we visited the southern sector, where we’ve spent the most time and have had the most encounters, calling it a day in late morning for Thanksgiving. At dinner, a long-time acquaintance of Frank’s described seeing IBWOs at a location about 10 miles from our search area from which we’ve had another credible-seeming report. We spent Friday through Sunday in the northern sector, which contains some extraordinary habitat, much of it old growth or nearly so. In this sector, sweet gums and oaks of 3-4’ diameter at breast height are not uncommon, and larger trees, like the one pictured, can be found from time to time.
Travel in the northern sector is extremely challenging due to blowdowns and deeply incised sloughs. On Saturday, it took almost the entire day to cover a total of three miles. One impressive feature of the area is the presence of large patches of cane that reaches as much as 15’ in some places. In some parts of the forest, cane is the main component of the understory.
It appears that some places within the northern sector have not been visited by people for several decades. In one apparent old growth area, the only litter we found was a Schlitz beer can and a 16 ounce glass soda bottle, both of which date to the 1980s. There were no shotgun shells or other signs of human presence to be found. Approximately 1/4 mile south we did find a hunter’s flagging that was several years old. This is difficult and seldom visited territory.
At 8:40 on Thursday morning, we heard some distant, intriguing kent-like calls. There were, however, several Blue Jays calling much closer to our location. We then visited the tree shown on the Project Coyote homepage that we found in May 2013. The decay is progressing, and there are many new insect exit tunnels through the remaining bark. It seems significant and mysterious to us that there is no sign of further woodpecker foraging of any kind on the tree. This tree is in within a known Pileated Woodpecker home range, and we believe that if the work were that of a Pileated there would have been multiple return visits by now.
Old feeding sign that has the appearance of the work we believe to be diagnostic is abundant in the northern sector, but we did not find anything that appeared to be fresh. We suspect this may be at least in part a seasonal factor and that scaling of bark is a more central feeding strategy during mating season and until young have fledged. Nonetheless, we were impressed by the abundance of feeding sign. These are several examples. We found the excavation in the last image to be somewhat different from typical Pileated Woodpecker work and therefore somewhat intriguing, although we suspect it was done after the bark had been removed. The wood showed no signs of rot.
We did not hear anything intriguing on Friday, but at 1 pm on Saturday, deep into the remote, untraveled area, we heard two ambient double knocks. The first of these was perhaps the closest to recorded Campephilus DKs I’ve ever heard in the field. Frank heard an additional DK or two that I missed. We then got two or three single knocks in response to a series of ADKs (anthropogenic double knocks). These knocks appeared to come from two sources, moving from slightly northwest of our location toward the south. On our way out of the area, we found an old snag with an intriguing cavity, as well as one being used by a sub-adult Red-headed Woodpecker. We returned on Sunday morning to place a game camera on the tree. At approximately 8:15 am, prior to setting up the camera, we did an ADK series (this within 200-300 yards of where we heard the DKs the afternoon before). We had several knocks, both single and double, in apparent response.
As peak search season approaches, we’re encouraged to have three distinct but connected areas where we’ve found suggestive feeding sign and have had putative encounters. While there have been no sightings in the northern sector, the contact rate is extraordinary, as is the abundance of feeding sign. To be continued . . .
Late last June, I collected several beetles and larvae from a suspected feeding tree in our search area. An entomologist has identified one of the adult specimens as Hesperandra (or Parandra) polita. All the adults were the same species, and we presume that the larvae were as well, although we were not able to preserve them for identification. Parandra polita is one of the few species specifically identified from the stomach contents of Ivory-billed Woodpecker specimens.
According to the Birds of North America species account:
“Most of the animal material (45% of the total sample, USFWS files fide Tanner 1942a) was composed of cerambycid beetles. Two species of cerambycids were identified as Parandra polita and Stenodontus dasystomus . P. polita is a long-horned beetle that has been described as “rather rare” in the s. U.S., but common in Mexico and Central America (Doane et al. 1936), thus potentially providing a specific dietary link between Ivory-billed and Imperial woodpeckers. These beetles feed on the heartwood of old and weakened hardwoods.”
It’s intriguing to have found a known Ivory-billed prey species on a suspected feeding tree.
Edited to add: We may in fact have found two prey species on suspected feeding trees; the other was an adult eyed click beetle (Alaus oculatus); Tanner found a click beetle larva fragment in a Singer Tract nest.
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.