March Recordings Revisited: A Compilation of the Calls for Easier Listening, Interesting Knocks, and Some Additional Analysis

If you’re interested in possible double knocks, I’ve made what may be some important new finds, so be sure to read the whole post and listen to the clips at the end.

In the meantime, I think this post will be of interest to many readers – from the new ones who’ve found the blog either because of the recent sighting or after reading about Project Coyote on the LABird list (thanks to Jay Huner for the mention) to other ivorybill searchers and aficionados to those who have had trouble hearing the putative ivorybill calls on the March recordings or didn’t want to wade through all the audio.

In the easy listening department, Steve Pagans has made a compilation of the clearest calls on Matt Courtman’s first, 2 hour clip recorded on the morning of March 15 using NCH software.

I tweaked Steve’s version a bit, amplifying it and applying noise reduction using Audacity, an equivalent program. Sonograms were generated using Sonic Visualizer, to my knowledge the best free program of its kind.

Both Steve’s version and mine (immediately below Steve’s) should make it considerably easier to hear many of the calls recorded that morning. Steve’s is somewhat cleaner, and mine is somewhat louder.

Steve’s extracts from Matt’s first clip:

With additional amplification:

Steve has done similar, shorter condensations of the the other two recordings Matt made. (The extract from the second clip adds little, so I’ve opted not to post it.)

Steve’s extract from Matt’s third clip:

With additional amplification:

The calls have a very consistent sonogram pattern (the stacks of three or more parallel horizontal lines), with an emphasis on the second partial (third horizontal line from the bottom). There are apparent tree squeaks in both clips that have a similar quality; the dominant frequency is similar, but the tree squeaks show more energy at that frequency. The second screen cap is a detail of the first, showing both calls and tree squeaks. The latter show a brighter orange, indicating more energy at a similar frequency to the calls’ dominant partial. The sounds are definitely different, but they can be hard to distinguish at the margins.

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Steve’s effort, which took many hours, inspired me to revisit the recordings and specifically to reexamine possible responses to Matt’s anthropogenic double knocks and Phil’s playbacks over the course of the more than three hours when Matt’s recorder was running. I had concluded that the ADKs did not seem to have had an impact, but on careful re-listening, I’ve amended that view. Matt’s knocks do seem to have stirred up calls in reaction and to have generated several possible single or double knocks.

Listening through the recordings and especially to the ADKs and their immediate aftermath was a time-consuming and difficult process, especially because the knocks are very loud and tightly spaced. Matt used two wooden blocks (rather than dowels and a tree trunk or a knock box) and did not follow a specific protocol. Overall, his approach was more aggressive than Frank’s or mine, both in terms of volume and number of knocks, and a somewhat more restrained approach is probably advisable in the future. Nevertheless, if you assume (as I do) that ivorybills were present on this morning, these recordings may provide some insights into the efficacy (or lack thereof) of ADKs in generating responses.

This return visit to the recordings also supported my view that the putative ivorybill calls (recorded in the old search area) that Phil played back generated no reaction at all from the suspected ivorybills on the morning of the 15th.  Blue Jays, however, appeared to respond, and I now tend to think those calls (though not all of those recorded in the old area) were Blue Jay, based on the apparent Blue Jay responses and on the harmonics. In retrospect, it’s unfortunate (but totally understandable under the circumstances) that playback of the Singer Tract recordings and other possible attraction methods weren’t tried. Perhaps another opportunity will present itself, although the events of March 15 were singular . . . thus far.

In the first of these two clips, the playback seems to have provoked Blue Jays to call faintly. In the second, in which the Blue Jay calls are easier to hear, they had been calling before the playback began.

Phil’s Playbacks:

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Sonogram of played back calls showing fundamental frequency, strong second partial, and strong higher harmonic at approximately 5000 hz. Presumed Blue Jay call is the faint horizontal line at bottom center with a frequency of around 2000 hz.

By my count, Matt did 7 sets of ADKS and performed approximately 205 knocks in all. I noted six possible double or single knock responses (of varying quality) in four of the six series. These knocks occurred within seconds of ADKs. The temporal proximity between the ADKs and the possible DKs and SK in response make it less likely that Matt and Phil (to a lesser extent) would have noted them in the field.

I’m posting the relevant extracts below in unmodified form followed by clips with the interesting knocks amplified using Audacity. They should be audible through a desktop computer, but headphones will help. To repeat a strong caveat: Matt’s ADKs are very loud (which made this analysis especially difficult). I should also reiterate that I don’t consider myself particularly skilled at analyzing recorded knocks; I don’t have the greatest ear for intervals and have no direct field experience with Campephilus woodpeckers; my ability to interpret sonograms is also limited. Nevertheless, I’m sure these sounds are neither shots nor industrial noise (or duck wingbeats). With one exception (the fifth knock, which sounds like a single to me), I’m also confident that Matt was not the source of the sounds. Some of inadvertent bumping together of his blocks should be audible at various points, and it has a different quality.

The first set of ADKs was the shortest, involving only six, and these were very closely spaced. The first ADK in the series produced a possible DK in response. Matt began the series 15 minutes and 52 seconds into the recording, and there had been a kent call at 14:59. Both a possible DK and a kent call can be heard between the first and second knocks. An additional kent can be heard after the third knock (omitted here).

Unmodified version:

Amplified knock:

I did not find any possible double knocks in the second and third series, and there were only a few kent calls – one during the second and three during the third. There was a possible double knock in the fourth series, at 1:48.22, two seconds after an ADK.

Unmodified:

Amplified:

During the 5th set, on the second clip, I found a possible single knock at 3:16. (Steve Pagans, who has an excellent ear, thinks it’s a closely spaced double.) I can’t rule Matt out completely as the source of this sound, but I think that’s a remote possibility.

Edited to Add: Playing the clip at a slower speed, reveals that there are two distinct knocks, the first louder, and leaves me convinced that Matt was not the source of this sound.

Unmodified:

Amplified:

Also on the second clip in the 6th set, there’s a possible double knock at 30:26, approximately 2 seconds after an ADK.

Unmodified:

Amplified:

On the final recording, during the 7th and final set, there’s possible DK after the 5th ADK in the series. It was preceded by a possible ambient DK about 50 seconds before Matt began the ADKs. The ambient knock is slightly buried behind some rustling, approximately three seconds into the recordings. To my ears, the DK in response sounds as though the first knock is softer than the second, something that’s uncommon but not unheard of for Campephilus woodpeckers. I’ve included both the entire relevant sequence and extracts in which I’ve amplified the knocks.

Unmodified clip with ambient DK and later DK in response to Matt’s 5th in a series of ADKs:

Ambient DK Amplified:

Amplified DK in response to ADK:

Finally, in listening to parts of Matt’s first clip again, I noted that there are a number of very distant kents. These are barely audible at normal volume and only faintly so on the amplified version. This suggests a highly mobile source (or sources) for the calls. It also suggests that there may be more calls on the recordings than the approximately 200 hundred I originally estimated. Steve noticed these calls too but elected not to include them in his compilation because the amount of amplification necessary degrades the sound quality. Thus, it may be difficult for some readers to hear these more distant calls.

The first few seconds of the extract below are unamplified to give a sense of the volume of other ambient sounds at the time. The kent calls come toward the end, and with one partial harmonic showing up faintly on the sonogram (the lighter colored dot near the left margin in the image below).

Amplified Distant Kents:

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Click the hotlinks for prior posts and pages related to the March recordings.

I owe readers the final installment of the “Bits and Pieces” series (hotlink is to the most recent installment). I anticipate that it will be my final post for this eventful year. Look for it just before Christmas.

 

 


More Recordings from March 15: Approximately Three Hours of Kent-like Calls and Analysis

On March 15, Phil Vanbergen and Matt Courtman recorded numerous kent-like calls at the same location where we heard several calls on March 11 and 12. Phil was able to record two of the March 11 calls. That capture is included in the post, along with Phil’s audio from the morning of the 15th. I heard two of the calls on the 11th; the second one in particular struck me as being consistent with the Singer Tract recordings; the first seemed a little low pitched to my ears, an observation that’s captured on the recording. Steve Pagans and I heard several calls on the 12th, but these were not recorded.

Matt obtained nearly three hours of audio, and to my ears the sounds are coming from 2-4 distinct sources; I had the same impression after listening to some of Phil’s clips. I have now listened all the way through Matt’s recordings several times and will share my analysis below. Matt and Phil are likely to weigh in later with their perspectives. I also have a couple of trip reports pending, so there should be a lot of activity on the blog in coming weeks.

To start with, I counted over 200 kent-like calls in all.

On the long clips posted here, I’ve edited out all of Matt’s ADK (anthropogenic double knock) series, which he did on the half hour. The knocks are very loud, as can be heard from the one trailing sound I’ve left in. I also snipped out several minutes of conversation between Phil and Matt. The ADKs seem to have led to more frequent calling and may have provoked some double knocks, something we may address in a future post.

Edited to add: On further review, there does not appear be a correlation between ADKs and more frequent calling. Clips like the one posted below can be deceptive. One kent-like call that overlaps with a knock has been deleted. There is also one possible knock in response. Caution, ADKs have not been completely spliced out, and they are loud. See bottom of page for brief clip and sonogram.*

Between 6:12 and 6:25 on the last long recording made that morning, there are five calls of differing durations and volumes, followed by what may be a double knock. Similarly, at the end of the full clip, starting at 14:14, 3 calls are bracketed by some potentially interesting knocks, 2 before and 1 or 2 after.

The first four clips below are shorter, amplified extracts on which the calls can be heard easily.

The first two of these are extracted from the final segment described above and include the interesting, tooting sounds and possible knocks.

The third clip includes multiple calls over 2 minutes and nine seconds, along with a wide variety of other sounds.

The fourth is four minutes long (pardon the airplane noise) and should provide additional context while also revealing some of the variations among the calls.

For those, like me, who don’t have professional sonogram software, I recommend using Sonic Visualizer – an easy to use, free program that enables you to watch the sonogram as you listen.

And for those who are unfamiliar with avian bioacoustics, this is a great place to start. I’m on a very steep learning curve myself and am prepared to stand corrected about any misstatements in this post.

Many of the sounds are audible on built-in computer speakers, but playback through headphones, earbuds, or external speakers is highly recommended.

 

I think these calls were likely made by Ivory-billed Woodpeckers. My perspective is based in part on the fact that I have spent all or part of nearly 40 days in close proximity to where the calls were recorded, starting in 2014. A considerable amount of this time was spent sitting quietly, and the total person hours spent in the area is well into the hundreds. We have had occasional kent-like calls, possible double knocks, and possible sightings over the years, but nothing approaching what transpired on the 15th.

Matt spent the morning of the 16th in the same location and did not hear any of the sounds, and Patricia and I spent 4 mornings and one afternoon there between the 23rd and 31st and heard no similar calls. I think this militates strongly against the idea that the source of the sounds is a common resident of the area.

Three alternative hypotheses have been suggested.

On the morning of the 15th, Phil proposed that the sounds might be tree squeaks. There appear to be multiple tree squeaks on the recording, some with similar pitches, but they bear little resemblance to the kent-like calls on the sonogram or to the ear. In addition, the calls sometimes come singly, sometimes in groups, and they vary in pitch, volume, and duration and seem to occur independent of wind velocity (on the 11th we noted that there was no wind.)

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Sonogram of first clip, showing apparent tree squeaks before and and immediately after two kent-like calls – the stacked horizontal lines right of center.

The first sound, at just after 4 seconds on the second clip, seems ambiguous. The sonogram is somewhat similar to the kent-like sounds, but the duration is very short, and it has a creaky quality. It’s also associated with the two creaky sounds that follow. These can be heard frequently over the course of the morning, and their appearance on the sonogram is nearly uniform.

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Sonogram of second clip showing tree squeaks.

One reviewer proposed Wild Turkey and Blue Jay as possible sources. I think turkey can be ruled out due to the absence of other turkey-like sounds associated with these very persistent calls.

Blue Jay strikes me as a more plausible alternative. Blue Jays can be heard at numerous times on Matt’s recordings. And Blue Jays are known to make kent-like calls, some of them very similar to known Ivory-billed Woodpecker sounds. This is likely not mimicry, since the most similar recorded calls I know of were obtained in upstate New York. The recordist noted the similarity. On the sonogram, the resemblance between these calls and either known Ivory-billed Woodpecker sounds or Matt’s recording is not as strong as it might seem to the ear. While they share a strong third partial, the Blue Jay fundamental is higher and some of the higher partials are considerably stronger.

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Kent-like, suspected Ivory-billed Woodpecker calls recorded by Matt Courtman on March 15, 2017. Note the relatively strong base frequency and 3rd partial, and weak 2nd, 4th, 5th, and 6ths.

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Kent-like Blue Jay calls. Note the relatively weak fundamental and strong second through fifth partials.

It’s also important to note that on the Cornell Blue Jay recording, the kent-like calls are intermixed with typical Blue Jay vocalizations. Over the three hours of Matt’s recording, kent-like calls occur during periods when Blue Jays are vocalizing and during periods when Blue Jays are silent.

Some of the kent-like calls have harmonics consistent with Cornell’s recorded playbacks of Singer Tract calls at 145 meters. Many are lower in pitch. Most have a considerably longer duration, although to my untrained eye/ear, some seem close to the 80-100 ms duration on the Cornell recording. More on duration below.

On March 28, I did some playback of Singer Tract calls using an iPhone and a bluetooth speaker. Patricia recorded them on a Roland Edirol R09HR digital recorder. I’m including the recording and the sonogram for comparison. Like Matt’s recordings, the second partial is strong throughout, and the 1st, 3rd, and 4th appear to be weaker than for the Blue Jay shown above.

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At various points, Phil also experimented with doing playback, using calls recorded in 2010 at the old Project Coyote site. (He also played back several other species – Red-bellied, Golden-fronted, and, possibly, Gila Woodpecker to gauge Red-bellied response, and Eastern Towhee out of personal interest.) Examples of putative ivorybill playbacks can be heard over the first 3 minutes of the fourth long clip posted above and also during the first part of the fifth. These sounds are longer but similar in tonal quality to the lower pitched calls. Their harmonic structure is different, however, with a fundamental at around 800 hz, a second partial at around 1600, and a fairly strong higher partial at approximately 5000 hz., and should be readily identifiable on the sonogram.

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Higher pitched playback calls, at middle left and far right.

Phil’s playbacks do not seem to have provoked any kent-like replies. Blue Jays can be heard during the same time frame, but it’s not immediately apparent whether the recorded Blue Jay calls are responses or merely contemporaneous vocalizations. This segment includes some Blue Jay vocalizations.

With regard to Blue Jays and the numerous kent like calls heard from March 11, 12, and 15: to reiterate, many hours have been spent in this vicinity, with close attention being paid to kent-like sounds. These are heard infrequently and never before in such quantity or over such an extended period. If Blue Jays in the area were making these sounds, we almost certainly would have heard and recorded many of them over the years. In addition, both Steve Pagans and Matt Courtman are experienced and skilled ear birders and neither thinks these are Blue Jay calls.

It’s also worth pointing out that another potential confusion call can be heard on the recordings – White-breasted Nuthatch. The sound is similar but much weaker, as should be clear from the amplified March 15 excerpt. On the sonogram, just below the amplified recording, the calls show up very faintly, with dominant frequencies of around 2200-2400 hz and a relatively strong partial at 1700-1800.

 

 

I encourage people to listen through and draw their own conclusions. Input from those with expertise is welcome.

While I can’t say if any of these calls are a perfect match for the Allen and Kellogg recordings (some may be), many of them are close on the sonogram and similar to the ear. It’s important to bear in mind that the Singer Tract birds were likely agitated when those recordings were made, even though Tanner described some them as being good examples of kents. It’s also important to read Tanner’s descriptions carefully, though as is so often the case, his writing can be opaque. Perhaps his most important observation was that “all of the notes have the same nasal, trumpet-like quality.”

According to Tanner, “The notes of the nuthatches are the only bird calls I know that sound like the voice of an ivorybill; the Ivory-bill’s calls are much longer and pitched higher than the calls of a White-breasted Nuthatch, are more in the range of a Red-breasted Nuthatch.” (Emphasis added.) By contrast, Hasbrouck, writing in the 1890’s, described it as being “exactly like the note of the White-breasted Nuthatch” only much louder and stronger.

Tanner’s reference to Red-breasted Nuthatches has always confused me. I’m very much in Hasbrouck’s camp; I think the Singer Tract kents sound far more akin to White-breasted than Red-breasted Nuthatch. Either way, most of the Allen and Kellogg kents are lower pitched than typical White-breasted Nuthatch calls, as are the ones on Matt’s recording. In addition, the Allen and Kellogg kents seem to be of similar in duration to typical nuthatch calls, rather than longer or “much longer”. This too suggests that they are not typical but are more rapid and perhaps higher pitched due to agitation. Tanner wrote further, “[t]he kent note, given in monotone or infrequently, is the ordinary call note. When the bird is disturbed, the pitch of the kent rises, and it is repeated more rapidly, frequently doubled, kent-kent, with the second note lower. The prolonged and slurring, kient-kient-kient call I always heard when two or more birds were together.” This call was never recorded.

According to Allen and Kellogg, “kenting varied a great deal” and a male bird called “loudly and deliberately”, again suggesting that many calls were of longer duration than those on the recording. Tanner’s notes also point to this variability. At one point, he wrote of “1 and 2 syllable yaps”; he has the Mack’s Bayou bird (whose voice he claimed he could recognize) making a “kient-kient” and also transliterated calls with “keent keent” and “yeenh yeenh” (Bales). These renderings all suggest a more drawn out call than those on the Allen and Kellogg recordings. George Miksch Sutton described the Singer Tract birds’ calls as, “strange, bleat like, not quite sharp enough for a woodpecker’s cry. It was slightly nasal in quality and it sounded to me like ‘Gip!’, with a hard g“. Sutton’s description also suggests that many kents had a fairly long duration.

Edited to add: similarly, several observers (Audubon, Beyer, Hoyt)  described ivorybill calls as “plaintive”; this too seems to imply calls of longer duration than what’s heard on the Singer Tract recordings.

Given the resemblance to the Singer Tract recordings and the lack of plausible alternatives, I posit that these calls are at worst highly suggestive of Ivory-billed Woodpecker.

*Possible knock and kent-like calls temporally associated with ADK series. Caution remnant ADKs are loud.

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Trip Report Feb. 20-24, 2015: Still More Smoke

Note: this is a very image-heavy post, and most of them appear ‘below the fold’.

Although we faced significant challenges during this trip, it was nonetheless a very productive one. I was joined by John Henry, the photographer who was with me when I recorded kent-like calls in March 2013. Work obligations kept Frank Wiley out of the field, except on February 24th. A flight delay and 1:20 am arrival at my hotel in New Orleans on the morning of the 20th limited my field time to a couple of hours on that day. I had planned to get in a final half day on the 25th, but wintry precipitation prevented it. Weather conditions were a challenge throughout – skies were consistently cloudy and dark; there was occasional rain; and temperatures fluctuated from the 70s on Friday and Saturday to near or below freezing on Monday and Tuesday.

On the afternoon of the 20th, John Henry and I went to the eastern sector, the most easily accessible part of our search area. This is the vicinity where a visiting biologist, Frank, and I heard double knocks during my last visit, and where we have found a significant amount of feeding sign since 2012. I found some fairly impressive, extensive, and recent bark scaling high on the trunk of a fairly distant tree. I was unable to examine it up close, but from a distance it appeared to be consistent with what I think is likely, if not diagnostic, ivorybill work.

Scaling2:20

On a non-ivorybill related note, the feral hog population seems to be increasing in our area, and they do enormous damage to the habitat, probably not in way that impacts the ivorybills we believe to be present, but their impact on forest ecology is likely severe. While they are hunted by some in the area, and don’t seem to be nearly as abundant as they are in Congaree National Park, for example, they are still a severe problem.

Hogs

 

Edited to add: This poor photograph of large, relatively slow moving terrestrial mammals, the best of several taken at less than 100 yards, illustrates just how difficult it is to obtain good pictures in this environment.

On the 21st, John Henry and I went into the habitat on through the northwest corner. This is an area of fairly recent blowdown, several deep, meandering sloughs, and dense blackberry thickets, making it incredibly difficult to explore. On more than one occasion, we had to retrace our steps and find a different route. I estimate that we were able to cover a quarter mile per hour. Traversing this area is hard on body, boots, and clothing, and it’s very difficult to pay attention to anything except the next step. We finally reached the site of the target tree featured in Frank’s Pros and Cons of Trail Cams and where I recorded a possible DK in response or reaction to an ADK. We decided to do a double knock series. Following Frank’s lead, I did a little pounding on the log before doing any DKs. Then I did a DK (I wasn’t recording, as I was using an external microphone mounted on my camera and figured I’d turn it on when I finished the series). Within approximately 10 seconds, there were 3 extremely loud single knocks that came from east-southeast of us. I’d estimate they were spaced about a half second apart and were no more than a couple of hundred yards away. Nothing else happened in response to the series. Although they didn’t have the resonance of typical woodpecker drumming, they didn’t sound like branches breaking, gunshots, or industrial sounds. There were no hunters in the immediate vicinity, no vehicles parked along the access road on our way in and out of the area, and we heard nothing remotely similar during the rest of the day.

On the 22nd, Frank and I made a pilgrimage to meet J.J. Kuhn’s daughter (known to us as Mrs. Edith) who had honored us with an invitation. We spent a delightful afternoon with her and her daughter, son, and son-in-law. They regaled us with many stories about Kuhn’s life, before, during, and after his time with Tanner. As readers know, we see Kuhn as the true master at finding ivorybills. Mrs. Edith is writing a biography of her father, so we’ll leave it to her to tell the story. During our absence, John Henry visited the northern sector and reported hearing a double knock late in the afternoon. He also spoke to two local hunters who claimed to have seen ivorybills. The elder of the two men said he hadn’t seen any recently but had seen a pair 15 years ago in the area that’s discussed in the first and last paragraphs of my previous trip report. This is the third local person to have claimed a sighting in that general vicinity.

The other person’s claim was of a sighting at the south end of what I refer to as the northern sector, so John and I decided to explore that area (which had not been visited) on the 23rd. As is so often the case, travel was complicated by deep, meandering sloughs, although it was nowhere near as difficult as what we encountered on the 21st. We did not have any possible auditory or visual encounters, but I did find one very impressive looking cavity (although not a fresh one) and a downed sweet gum with very extensive and fairly recent bark scaling.

cavity2:23:13

 

Anotherlimb2:21

HangingBark2:21

John next to the main trunk to provide a sense of scale.

John next to the main trunk to provide a sense of scale.

FullViewMainTrunk

This type of work is similar to work found last year. and while it doesn’t exactly meet the criteria I’ve laid out previously for what’s diagnostic, I strongly suspect that it is Ivory-billed Woodpecker work, beyond the physical capacity of a PIWO. The bark was tight and difficult to impossible to remove without an implement.

Frank joined us on the 24th, and we entered the eastern sector farther north. The hike in at this location is long and difficult, but our efforts were rewarded, and we gained quite a few new insights. Once we were well into the bottomland area, we experimented with doing some playbacks. Frank played some Pileated Woodpecker calls and drums, which stirred up a good deal of activity. One Pileated flew in silently, and several others called with the rapid, “cackle” call and drummed in the distance. He then switched over to playing the Singer Tract recordings, and two more Pileateds flew in to the trees just overhead. They drummed and did the “wok” call, apparently in direct response to the recording. It is at least intriguing that playback of ivorybill calls would produce such a response from Pileateds.

We packed up and headed deeper into the habitat and found a sweet gum with three large, oval shaped cavities.

The lower cavity is the most obvious; the other two are near the top, partially obscured by branches.

The lower cavity is the most obvious; the other two are near the top, partially obscured by branches.

About a hundred yards away, I came across another downed sweet gum with extensive and suggestive scaling and large bark chips underneath; one of the chips, shown below, appears to have strike marks that are suggestive of IBWO, similar to the ones discussed in this post. I failed to get clear photographs showing the extent of the work on this downed tree, partly due to angle and lighting and partly due to the events discussed below.

2:24:barkchip

Large bark chip with apparent bill strike.

Large bark chip with apparent bill strikes.

Detail of downed scaled sweet gum.

Detail of downed scaled sweet gum.

This limb, which was somewhat punky, had been fully stripped of bark, apparently after it fell. Also note the scaling in the background.

This limb, which was somewhat punky, had been fully stripped of bark, apparently after it fell. Also note the scaling in the background.

There was a nearby hickory snag that had been heavily scaled in the manner that I think is diagnostic, although not recently.

Old2:24:15

John had moved some distance away while Frank and I examined the tree, and I started taking pictures. As we were doing so, we heard two distinct double knocks in close succession, roughly from the south. This was at approximately 11:15 AM. We remained in place for 30-45 minutes at which time we played back the Singer Tract recordings. John had moved closer to us. Within 30 seconds to a minute of the playback, Frank and I heard a kent-like call. We disagreed about the direction. Frank had it from the Northwest, and I thought it was from the West. Between 30 seconds and one minute later, a large black bird flew in from the west at about 85 yards. My view was fully obstructed, but Frank saw it for several seconds before it took off, at which point John saw it but could not distinguish any field marks.

We proceeded through some very impressive habitat and found some additional scaling in the vicinity, some on a hanging limb and some more on a downed sweet gum. I have now found five downed sweet gums with this type of extensive work in the past year and nothing similar on other species (I did find similar but much less extensive scaling on a downed persimmon, an uncommon species in our area.) This may be significant

Suspendedscaling

2:24:15scalingnorth

The quantity of suggestive and recent bark scaling I found on this trip relative to time spent was remarkably high, as was the possible encounter rate.

I hope to return the search area in about a month and may do one or two posts on other subjects before then. Stay tuned.


Trip Report – December 26, 2014-January 3, 2015

Weather conditions were poor for a good part of this trip, but we did the best we could under the circumstances.

I flew from New York to Louisiana on Christmas Day. During a layover in Dallas, I was uninterested in the food offerings in the terminal from which my puddle-jumper flight was slated to depart. I hopped on the tram to the international terminal and found a place to have lunch. There was a young guy sitting at the table next to mine, and we started talking while waiting for our checks. It turns out he grew up within 15 miles of our search area and thinks he saw an IBWO while hunting near his childhood home about ten years ago. I did not press him for details, but it was clear from the conversation that he knows Pileated Woodpeckers; I was also confident that he was sincere. Leaving the coincidence aside, it’s astonishing how many people in this part of Louisiana claim to have seen IBWOs in hardwood bottoms.

During this trip, we also encountered a couple of duck hunters who were already aware of our search. One of them said, “If I saw one, I wouldn’t tell anybody,” which is considerably less worrisome than what I’ve heard people say in other places. The big concern for most is that finding IBWOs means the end of hunting in the area. We assured him that would not be the case. The thing for searchers to stress in this context is that success will mean that more forest is protected.

On Friday, December 26th, Frank Wiley and I went to the northernmost sector, traversed a swath of tornado blowdown, and went to the site of our game cam. There is nothing of great significance to report from that day, except finding the somewhat unusual excavation discussed in this post.  There is a good deal of old suggestive feeding sign in this area, but we found nothing fresh.

We returned to the same location on Saturday and aimed two Reconyx cameras at the target tree that will be shown and discussed in an upcoming post that Frank is writing and will complete when he recovers from the flu. We hope that having two cameras in one location, with different orientations and shooting cycles, will yield better results than deploying just one.

At a little after noon, Frank heard a single knock coming from the blowdown. It was followed by calling from a Barred Owl, a Pileated Woodpecker, and a Red-shouldered Hawk. On the full recording of the ensuing events, I can be heard saying “I thought I heard a knock out that way.” I had forgotten about this until I listened to the recording. Weak possibles are so frequent in our search area that I tend to dismiss them. The knock I heard must have come from the blowdown as well, since I pointed my camera in that direction. Frank did a double knock, and I recorded the “response” discussed in my December 27th post.

We left the swamp ahead of the rain on the 27th, and it rained heavily through the 28th. On the 29th, we were joined by several biologists and divided into two groups. I tried to take my group to the area where I recorded possible ivorybill calls in March 2012, but water levels were too high to do much, so we went to explore some new territory to the northeast. A map of the logging history suggested that some of these woods would be very impressive, but in comparison to some of the other patches, we did not find this to be the case. There is a large area of blowdown that merits further attention, and we know the habitat south of the blowdown to be outstanding; there was a good concentration of old feeding sign near the edges of the blowdown. There are several other bottomland areas in the northern and northeastern sectors that we haven’t visited yet and that appear not to have been logged since the early 20th century (1905, 1910, and 1916).

Frank took the other group into an area that has been surveyed a little more. One member of his team heard a weak possible double knock.

On the 30th, the weather was cloudy, windy, and cold. We took our three remaining guests to the site of the game cams to give them a sense of the scale and the context for some of the images to be discussed in Frank’s post. The general view was that the blowdown might be an important area. We hiked out at a little after 1 pm, and two of our guests departed. We took our remaining guest to the easternmost sector, a narrow corridor of mature bottomland hardwoods around a smaller stream. This area has had concentrations of fresh scaling in past years. At around 3:30 pm, after doing an ADK series, Frank heard two double knocks a couple of minutes apart. Neither our guest nor I heard them, but approximately two minutes later, we both heard a distinct DK that Frank missed. We disagreed about direction but both thought it was more consistent with typical Campephilus double knocks than the one I recorded on the 27th, with a shorter intra-knock interval and a softer second knock. We had no doubt that it was a double knock on a woody substrate.

On the 31st, Frank and I explored a mostly unvisited area, to the south of what Frank calls “Jurassic Park”. This is one of the widest swathes of bottomland hardwoods in the area, and it is very impressive; there are many patches of open canopy forest, with massive superdominant oaks and sweet gums like this one, which has a DBH of 4’2”.

Frank Wiley with massive sweet gum

Frank Wiley with massive sweet gum

We’ve only scratched the surface in this very large sector (which includes Jurassic Park) that our history suggests was last logged in 1908.

There was abundant scaling scattered throughout, mostly old, with one sweet gum (?) showing a large area of fresh work fairly high up.

Old scaling with large exit tunnels

Old scaling with large exit tunnels

Recent scaling that is intriguing but does not quite meet our diagnostic criteria because it shows some signs of layering and has a couple of small foraging pits

Recent scaling that is intriguing but does not quite meet our diagnostic criteria because it shows some signs of layering and has a couple of small foraging pits

While this fresh scaling does not quite match the criteria for what we think is diagnostic, since it shows some signs of layered working and has a couple of small foraging pits, it is still quite extensive, and at least from a distance, the limb appeared to be live or very recently dead. Some large exit tunnels are visible on close examination.

Also, while in this sector, we did an extended playback of the Singer Tract recordings. The playbacks did not generate any suggestive sounds, but several American Crows and two Red-Shouldered Hawks came in to investigate. The crows called, but the hawks did not vocalize. We don’t know whether the response of other birds to ivorybill sounds or imitations thereof is an indication of presence, but we are intrigued by it. It happens frequently in our area. Red-shouldered Hawks, in particular, react strongly to double knocks.

Weather was a severe problem on this trip, preventing us from going into the field on December 27th, January 1st, 2nd, and 3rd. On the 2nd I made a brief visit to the area described by the man I met in the Dallas airport. I was reluctant to go off the main gravel roads in my small, 2-wheel drive rental, and there was no obvious public access to the narrow stream bottom. I drove through a recent clearcut of about 40 acres. This looked to have been a stand of mature hardwoods. There is some measure of connectivity with our search area, and there are numerous smaller riparian corridors in the region. If birds are breeding in this part of Louisiana, there are ample possibilities for movement and dispersal through habitat that is not quite as impressive.


Recordings from January 2010

When I began blogging on WordPress, I mentioned that I’d be posting sound clips from our old search area that were available on the old Project Coyote site, but I’ve been somewhat undecided about it and wasn’t sure I could track down all the material, a problem I’ve now solved. The most interesting audio was obtained between January 24-26, 2010. Archived selections from those recordings and accompanying sonograms are available through the Wayback Machine, and you can click on the links to hear the clips. Some of these were recorded in the field on handheld devices, while others came from remote units provided by Mark Gahler.

In addition, to these selections, I thought I’d take the opportunity to post Frank Wiley’s entire recording of the extended auditory encounter that took place just after noon on January 25th so that readers can hear the full recording as well as the extracts. Six people were present when this incident occurred, and it’s unusual in recent IBWO history, not only for the number of people present but also because putative double knocks and kent calls were heard during a single event that appeared to involve at least two birds. See below for a little more about the old search area, how we got there, and what transpired between Summer 2009 and January 2010. This is the same area where we obtained the suggestive camera trap photos. The adjoining parcel was logged between November 2010 and January 2011, and there has been little indication that IBWOs may be present since that time, although we suspect they may still be using one or more of the nearby Wildlife Management Areas. Frank’s complete 58 minute field recording should be of interest to the dedicated among you. If you’re wearing headphones, note that there are some clarinet toots at the beginning; a possible kent call follows soon thereafter:

001_FOLDER01_010_Frank 2_10012501_2010_01_25 Audio 6 Witnesses

The search effort was inspired by what seemed to be a credible report from a resident of rural East-Central Louisiana. This individual, who passed away shortly after Frank Wiley arrived on the scene, had attempted to report sightings of ivorybills for a number of years but had been dismissed. When Frank interviewed him, he was not only insistent that birds were present in the area, he corrected the drawings that are included in the Louisiana Game Guide.

 

Screen Shot 2014-10-17 at 1.35.47 PM

The red shapes at the upper right are his rendition of the difference in shape between and ivorybill and pileated wings. He showed the crest as somewhat more erect in flight and perched. Perhaps most significant, he accurately depicted the female crest as considerably more erect than the game guide’s version (the red pen was used to highlight the differences not to show color.) I did not have the privilege of speaking to him, but Frank Wiley has told me he was very emphatic about these corrections.

During almost weekly visits to the property and surrounding locations between August and November 2009, Frank had several possible sightings, one of which involved three birds. In two instances, he obtained photographs, but these are of birds in flight at some distance and do not show definitive field marks. In addition, he heard suggestive knocks and kent calls on numerous occasions and recorded a number of the knocks.

I made my first visit to the location in November, 2009 On November 24th, 2010, during a stakeout of the location where the first of these photographs was obtained, we heard but did not record an extended series of calls, lasting approximately ten seconds, and coming from the general vicinity of the sighting described below. These calls were unlike others that have been recorded by contemporary searchers and resembled those documented by Tanner and Allen at 03:14 on the Singer Tract recordings.

On November 25, 2009, Frank and I were staking out a feeding tree when a large woodpecker flew into the top of nearby pecan. The bird was obscured by foliage but was moving around in the canopy as I tried to observe it. Frank moved and flushed the bird, and I got a brief glimpse as it fled, but only enough to notice white on the wings that appeared to be too extensive for a pileated. What was perhaps more significant about this sighting is that we both heard loud, rapid, Wood Duck-like wing beats, at a distance of approximately seventy-five feet. Later that day, I  flushed a pileated at much closer range and the wingbeats were considerably softer and muffled sounding. We placed a camera trap in this location and the second image on this page was obtained there a week later.

Between January 24-26, 2010, Bill Benish, Ross Everett, and Frank Wiley had possible sightings. Everett, McCaslin, and I heard possible kents on the morning of January 25, and shortly after noon on that day, all six participants had an extended auditory encounter that was recorded in part by Wiley, Benish, and me on separate recording devices; a couple of minutes had elapsed before team members were able to activate their recorders. All team members heard multiple kents and double knocks during this incident. We believe that two birds responded to the banging of a tin roof on a deer stand in the vicinity. Just before sunset on January 26, Benish heard and recorded a double knock. In addition, Mark Gahler’s remote recording devices captured possible kent calls on January 25th and 26th.


Kent-like Calls Recorded March 2, 2013

Since summer is here, and things are slow, I’ve reconsidered my decision not to post audio obtained in the course of our searches (although I’m not sure I’ll repost old audio from the original search area.) We did not record anything of note during 2013-2014, although we did have a number of auditory encounters. It’s not feasible to keep a recorder running at all times, so when interesting ambient sounds occur, it’s only possible to capture them when they go on for an extended period. In these situations, it’s a judgment call as to whether to approach the source of the sounds, try to record them, or a mix of the two.

These recordings were made on March 2, 2013, and I have included my notes to provide details and context (location redacted.) On the morning clip, the calls can be heard at approximately 0:03, 0:17, 2:04, 3:36, and 3:47 (two calls in very close succession with the interval almost indiscernible to the ear but evident in the sonogram). On the afternoon clip, the only call captured is at approximately 0:52. On the morning clip, there are toots on a clarinet mouthpiece at approximately 0:25 and 1:30, so beware if you’re listening on headphones. The first clip can be played directly from this page. Click on the link to play the second in its own window. I can only hear the call on the second clip with headphones.

Although the duration of the calls appears to be consistent with the Singer Tract recordings, the base frequency is considerably higher, approximately 920 hz.

John Henry and I were ***** on Saturday March 2, 2013. Conditions were mostly cloudy and cold.* Winds were strong (gusts probably around 20 MPH and not many birds were calling). The morning had been active, but as winds picked up, birds went quiet. At approximately 10:15 am, several crows were calling loudly, but I heard 2 intriguing calls behind the crows. I asked John to stop and be quiet. The calls continued, sporadically, for the next 30-45 minutes. I was able to record some of them. We both estimate the distance at around 200 yards and agree that two birds were involved. We both agreed that the calls were mobile and over the course of the sequence, they came from at least three directions. We tried to follow the calls but did not see anything.

Most calls were singles, but in a couple of instances, a first call was followed by a second one within a couple of seconds. The pitch of the second call seemed lower. The duration of the calls seemed to be short. They lacked the intensity of the Singer Tract recordings, but were clearly not Blue Jays, nuthatches, or tree squeaks.

I blew on a clarinet mouthpiece. The calls continued, but neither of us had the impression that there was a response.

At the end of the sequence, John heard two additional calls that I missed, and we found large bark chips at the base of a tree that was in the vicinity from which he had heard the calls. We had walked through this exact location before the calls began and had not noticed the chips (which I normally would have done.)

Between us, we heard a minimum of 18 Ivory-billed Woodpecker-like calls in the morning.

We left the area and returned late in the afternoon. At approximately 5 pm, we were at the spot where we found the bark chips. At this time we heard approximately a dozen more of the same calls and were able to record a couple. The first call I heard seemed a little off, as the note seemed to be doubled, one in immediate succession after the other.** This only happened with the first one. The others were virtually identical to those heard earlier in the day. A white-breasted nuthatch called during this sequence, and there was no possibility of confusion.

*The two nearest weather stations reported lows of 27 and 30 and highs of 47 and 49 respectively. Temperatures in the search area were likely slightly lower. When the morning calls were recorded, temperatures were in the mid-30s.

**This was what I wrote at the end of the day, without consulting any literature. Of course doubled calls are described by Tanner and occur on the Singer Tract recordings.

We are not claiming these as Ivory-billed Woodpecker calls, but several ornithologists have been unable to identify them. The sound and base frequencies are consistent with calls recorded in the old Project Coyote search area.

R09_0012

Edited to add: Here’s a sonogram showing the two calls that came in very close succession at 3:47 on the morning recording. I was unable to tease out anything but the base frequency. Sonogram-1 copy