Monday, August 31, 2009


Copulation bustin' out all over...

April 22, 2008

Over the previous two weeks, Scott and Melinda had both spent additional time in the field, watching the sight lines gradually fill in with leaves and hearing the woodpeckers quiet down as the nesting season got underway. Neither had any encounters with the MIMDKWTFII, nor any sightings of strange woodpeckerish creatures. My time had been occupied with the rest of life, punctuated by e-mails containing copies of Reconyx images with blurry blobs in them. These were coming alternately from the now-infamous Illinois freelancers and from another locale that has not yet chosen to make any of their findings public. It's a bad sign when an attached image has to come with detailed instructions on even finding the object in question in the frame; I was growing to really dislike Reconyx images!

I had arrived at the turnoff from Great River Road about 11:30 this morning, finding Bob's truck parked just off the levee. The water had dropped considerably since the beginning of the month, so I gave it a "test wade" to check the depth. The lowest part of the road to the barn was right at the beginning; I knew if that was workable I'd be clear for another mile. I never got deeper than about 10-12" and the road surface felt stable and firm, so my truck and I went for it. No problem. I was obviously the first vehicle in since March -- as I continued on to the barn I had to stop every 100m or so to move logs out of the road. I got to the barn around 12:30, with big dark clouds approaching from the west. I stayed at the barn to set up camp while the downpours passed, wondering if Bob had managed to get out ahead of the rain.

About 2:00 p.m. the weather cleared, so I put my kayak in at the edge of the swamp and paddled to Rhodes Lake. I spent the rest of the afternoon around the south end of the lake and exploring a bit back into the woods. The swamps were extremely noisy. Between turtles, beaver tails, branches falling, etc., there were banging, cracking, splashing, and slapping sounds all over the place. This was a recuring theme through the week -- high background level of noise from which possible woodpecker sounds had to be sorted out. Plus, in mid-afternoon it was obvious that Highway 88 reopened as the bangs and bumps from traffic on it resumed. Nothing double-knockish jumped out from all this background noise. The most unexpected and false-alarm triggering sound was a new one on me: copulating Wood Ducks. When the drake mounts the hen he beats his wings hard, making a short rapid series of rather loud slapping sounds against the water. It seemed the south end of Rhodes Lake was the site of the local Wood Duck love-in, as these sex-slaps were ringing out with distracting frequency. They did not resound through the woods for hundreds of meters as the sounds from the MIMDKWTFII did, but they could turn your head if you were within 100m of them or less.

Now that they had leafed out, the trees were identifiable to species. I discovered why I had not been able to recognize the species I mentioned earlier that grows tall (but not straight) around Rhodes Lake with often a lot of dead wood near its summit. I had not recognized them because I had never seen such huge ones before -- they were black willows (Salix nigra). Most of the other trees in this area were red and silver maples (Acer rubrum and A. saccharinum), with southern hackberries a.k.a. sugarberries (Celtis laevigata) dominant on the higher ground. A maple/willow forest is indeed not even remotely what is thought of as ivorybill habitat; though as I said already these were the tallest and most impressive black willows I had ever seen. It certainly provided good woodpecker habitat in general, however; the willows and silver maples are short-lived pioneer trees and these individuals seemed to be approaching the end of their life cycles. I would later find that this "overmature" maple/willow association was widespread through the sloughs at Moss Island, growing where I would have expected a cypress/tupelo association. Cypress was restricted to isolated sprouts and a few big "cull" trees; tupelo was nonexistent as far as I could tell. The simplest explanation for this pattern is that the cypress sloughs were logged out completely in the early 20th Century and this pioneer bottomland hardwood association had grown in to replace it. The pioneers were now starting to die off, likely to be replaced by red maple, green ash (Fraxinus pennsylvanica) and hackberry. Cypress did not seem to be making a comeback.

I returned to the "put-in" (the point where Rhodes Lake Road emerged from the water as it left the forest) at dusk, beached my kayak, and walked back to the barn to retrieve my pickup. A small white pickup holding two men and one woman passed me headed in the opposite direction (towards my boat) as I walked out. Almost immediately after they got to the edge of the swamp, I heard the klunking sounds of my kayak being messed with. I hurried to the barn, knowing that if I had my truck I'd be able to block them from getting away on the single-track, mud-bordered road. As I neared the barn there is a spot where there is a clear line of sight back to the put-in. I could see that one of the guys was off playing with my kayak, meanwhile the other had the woman bent over the hood of his truck and was doin' th' nasty. I sped on to my truck and drove back there as fast as the muddy road allowed. By the time I caught up with them, everybody's pants were pulled back up, they had loaded my boat and paddle into the back of their truck, tied the kayak in, and the one who hadn't been preoccupied with the business over the hood was wearing my PFD. They were drunk as skunks. They babbled lamely about "well hell how was we 'spose to know whose stuff it was?" to which I gave the obvious answer of "You f'ing SAW me walking up the road a hundred yards from the f'ing boat, who the f' did yo think it belonged to and where the f' did you think I was going?" (I left out the natural conclusion to this statement, "you f'ing drunk-ass morons!"). The woman joined in with "I told you it was his stuff, I told you he was coming back for it, I told you to leave it alone!" which didn't do much to help their case. They unloaded my boat, cutting the bow line since they were too drunk to figure out how to untie the knot, then made to get back in the truck and drive off. I stopped the one who was still wearing my PFD and said "What about my life vest?" He acted surprised; he might have been drunk enough that the surprise was real, and said "Oh, is this yours too?" I answered "What the f' do you mean is it mine too? It was stuffed up inside my f'ing boat, who the f' do you think put it there?" He gave me the vest and they jumped in the truck for their getaway. Apparently my impression of a pissed-off Charles Manson successfully intimidates the local rednecks. To paraphrase a biker acquaintance, it's amazing how effective an angry look and a lot of facial hair can be. A healthy dose of profanity doesn't hurt, either. As they drove off I wrote down their tag (TN plate, 833KKT, Lauderdale County), then loaded up my gear and headed back to the barn.

On the way I stopped at the house to talk to the residents. They had returned just an hour earlier after having been flooded out of their house for a full month. The house itself does not flood, but all road access gets cut off. In their younger days they just waited the floods out, but the daddy of the family, Gordon, had developed chronic health problems so they were no longer comfortable with being stranded. Gordon and his wife Judy had some pretty interesting stories of strange woodpeckers they had seen and heard in the woods there over the years; Gordon in particular had some very intriguing descriptions of vocalizations he had heard coming from these strange woodpeckers. I knocked on their door to see how things were going and tell them about the would-be thieves in the neighborhood.

I was immediately greeted by cries of "We saw the bird!"

Other posts in this series:

Thursday, August 27, 2009

Conflict, Confusion, and RoboBirders

For the remainder of their time in Tennessee, the Cornell crew only made it out in the field for one more full day, April 5th. On the 6th they did put in a half day, but that was mostly dedicated to retrieving Reconyx cameras. My info about these days is second hand, passed to me via Scott, as I was 160 miles away at the time. Apparently on the 5th Leighton heard a double knock while he was in the woods east of Rhodes Lake, with the sound coming from the south. According to Scott, Leighton said that if he had been in the tropics he would have identified what he heard as a Pale-billed Woodpecker, a sound he is familiar with. In Tennessee, on the other hand, he didn't know what to make of it. Do any of us? All told for their week in Tennessee, the augmented Cornell crew had three full field days plus one short take-down day. The crew ranged from 4 to 7 people each day, in 4 to 6 boats. Two double knocks were reported, no sightings, no kentings. And so it goes, on and on and on... It seemed that nothing would ever change.

Then the ARU results came back, which changed things, but not necessarily for the better.

Earlier in March, Scott and Melinda had deployed two automatic sound recorders (ARUs), borrowed from Cornell, for about a week at several places within the "hot zone." The data had been sent to Ithaca for processing, which is time-consuming. The analyses were finally complete right as everyone was returning from the latest excursion to Moss Island. Evidently one of the units malfunctioned, so there was only one machine's worth of data. I was not actually privy to any of what transpired about this first hand, but I gather over the course of a couple of conference calls, some things were said, misstated, and/or misunderstood that lead to some heated discussions.

The starting point is this: the only ARU that recorded data yielded a large collection of mechanical banging sounds but nothing that passed the screens as a candidate double knock under the criteria developed by Cornell. None of the human double knock detections were in places or at times that put them near the operating ARU, so no cross checking was possible. This was disappointing, but given a single deployment by only one machine this isn't really surprising. But then it all got complicated. Somehow things were said or construed, and then related to me on down through the telephone game, that left me with the impression that the Cornellians had concluded that we couldn't tell a double knock from a hole in the ground, and all we'd been hearing was these random mechanical noises that we were imagining were double knocks. This was, to say the least, kind of insulting. When I asked about the double knock that had been heard by one of their own crew, the (again second or third hand) answer I got was that Leighton had said he didn't know what he had heard. Apparently it was never quite as bad as it sounded to me, and it was mostly straightened out in a few days, But it reminded me of something that my wife's boss at a Federal environmental research lab had told her about science in Academia and government. Fair warning: I am going to use a time-honored four-letter Anglo Saxon word, unaltered and undisguised. The story really doesn't work as well if you sanitize it.

If you are a scientist at any sort of institution, you have three crocks of shit in front of you. One of them is your own shit, one is your friends' shit, and one is everyone else's shit. No matter what kind of scientist you are, your official position has to be that your own shit is gold, your friends' shit is silver, and everyone else's shit is shit. But if you are in Academia, you have to do more than just say this. You have to actually *believe* it.

Before anyone thinks I am accusing Cornell of being unusually and inordinately difficult, proprietary, or dismissive, think about your own dealings with groups, teams, and institutions under situations of pressure and frustration. These sorts of conflicts are extremely common, downright normal. It's just the way people are. The Man Behind the Curtain at the FWS (yes, there is one; let's call him "Jacob") and I talked over this situation a fair bit. He reminded me that there was a lot of frustration all across the region, with every crew feeling stuck in the rut of finding "something but not enough." Still, even though there were disagreements, on the whole the projects were doing a pretty good job of cooperating and sharing information internally, even if this was still being kept mostly out of the public eye. He also reassured me that as far as he could tell, Scott and Bob had successfully clarified the situation and the Tennessee position. To this day, though, there have been no further field collaborations between the Arkansas and Tennessee projects since all this came down.

Putting all the institutional drama aside, let's look at some of our own shit from Moss Island. I've heard 12 of the ARU samples. Most of them are clearly what I now call the "river noises," the off-site banging sounds that seem to mostly be associated with barge traffic on the Mississippi. Some of this is also from truck traffic on Highway 88 and Great River Road. A typical example is this (click the sonogram for a larger image, click the link below it to hear the audio):

Listen to the audio clip

Three things to note here:

1. The bangs themselves: They are generally long-echoing. They are very loud for the most part, and several kilometers away, so there's a lot of reverberation going on en route to your ears or your microphone. On the sonogram this shows as a long rightward smear of the signature. Also note how they are fairly "tall," covering a broad range of frequencies.

2. The pattern of the bangs: They tend not to occur in isolation. One loud BANGang is going to be preceded and followed by a bunch of other bangs in other patterns.

3. The other sounds: Associated with the bangs are various whining and churning sounds, which show in the sonogram as horizontal lines that fade in and out. These are motors and such.

This specific example is some of the "river noises," but similar things apply to human-made noises in general, be they gunshots, construction sounds, vehicles, etc. They tend to be associated with other human noises and recur in patterns that make their origins clear. These sounds are very familiar to us; they are not what we have been calling double knocks. Of the 12 clips I was provided, 9 represent these "river noises." All were recorded between 9:09 and 9:26 a.m. on March 6, 2008; in other words they all represent one single 17-minute long event. I've heard many of these events. They all come from the same direction (west), are nearly always accompanied by audible engine sounds, and are very easy to identify and eliminate as being of no interest at all.

This next clip is a "bridge whump," the sound made by a heavy vehicle passing over the expansion joints on one of the many highway bridges within a couple of miles of Moss Island. It was recorded on March 8, 2008 at 6:41 a.m.:

Listen to the audio clip

As the sonogram shows, this is actually a fairly mushy sound. It isn't crisp and sharp like the "real thing" would be. This mushiness is noticeable to the ear as well -- they sound distant and sort of muffled. You can also hear, and faintly see, the long trailing echo again, typical of loud, distant human-caused mechanical sounds and gunshots.

One more clip illustrates some other interesting features. This was recorded on March 11, 2008 at 3:35 p.m., the afternoon of the day on which I heard my first double knocks. Scott, Melinda and I were all sitting quietly at Hushpuckett Lake at this time, hearing nothing of interest:

Listen to the audio clip

This is the only one of the 12 clips I was provided with that even required a second listen. Sometimes, depending on your headphones and software, you will hear something that sounds rather like a woodpeckery double knock in the middle. Two things to note about this clip:

1. The spectrum of the knocks or bangs is different than the mechanical bangs shown before. It is focused in a narrower range of frequencies, centered in this case around 400 Hz. It also lacks the long, smeary trailing echo. This low, narrow frequency range is what gives real double knocks their resonant, sonorous, woody quality. Just to make matters confusing, a similar effect can also be produced by whacking on the hull of a boat, or banging your boat in to a tree. It's a predominance of lower frequencies with a fairly distinct peak at a specific tone, as compared to the mechanical bangs (and gunshots) that include much more high-frequency sound and not such a strong dominant pitch. The two loudest knocks in the middle of the sonogram are actually not that bad of a match for a "real" double knock, in terms of quality and timing, though the second knock is a bit high in pitch compared to the first one.

2. There are multiple other knocks in this clip, all within a little more than a half second. The pair that can sound like a double knock are the second and third notes. About 0.5s before them (just to the right of the vertical bar marking 6.0s in the sonogram) there is a fainter but distinctly audible knock; right after the pair are two other faint knocks that to the ear get swallowed by the middle louder sounds: "knock......KNOCKNOCKockknock." It is impossible to tell if these sounds are all from the same source, since the ARU gives you no information at all about direction and no real clues as to distance. If you isolate just this one second of the clip and play it in a continuous loop with the volume turned up, you can hear all five of these knocks and the superficial similarity to a double knock fades quickly. To a live observer hearing the sound in person, I suspect all that extra banging would have been more evident and it would not have come across as a double knock at all. My guess as to the source of these sounds is either one or two loudly foraging Pileateds, or a distant boat banging through the woods.

I have never been a big fan of Robobirders, like ARUs and automatic cameras. To me the absence of all the extra contextual data you get from a real, live person is a near-fatal flaw. The advantage of continuous surveillance and an "objective" record to me is largely outweighed by the time- and resource-consuming nature of the data processing and the ambiguous nature of all these "objective" results, mandating a massive amount of "subjective" (and controversial) interpretation. A large investment in time and resources has gone into robobirding for Ivorybills in recent years, resulting in only a modest amount of data the significance of which no one can agree on. For the most part it has yielded exactly what the human beings have produced: mysterious sounds of indefinite origin, and visuals that might suggest but come nowhere near proving. I realize they have their use as a compliment to the in-the-flesh field observations; but when the robots begin to take precedence over the humans that just isn't right.

Some might argue that this very ability to look at the sonograms and analyze their detailed characteristics is exactly why they are more valuable that reports from observers. But in fact, the Cornell analysts were not able to identify the sounds in those first two clips as anything but "mechanical sounds" of undetermined origin. I can identify them as "river sounds" and "bridge whumps" because of my actual "subjective" human experience at the site. And I would argue strongly that all these distinctions that can be picked out from the spectrogram are even more obvious to the ear of an experienced, skilled, discriminating observer (the only kind of people we should be fielding on these expeditions). All of these sounds are vastly bigger, richer, and more complex than what gets picked up by the RoboBirders and visualized on the sonogram. The live observer perceives, processes, and incorporates all this additional information. Ideally s/he also manages to capture a recording of what s/he observed; but lacking this does not mean that his/her observation is meaningless, or even less valuable than an ARU clip or crappy blurry video. I could just as well argue that the ARU data are meaningless because they are not corroborated by the experience and judgement of a skilled live observer.

Though I will get in to this more towards the end of my saga, we did eventually manage to get a recording of an example of the sounds that we live observers had been calling "Campephilus-like double knocks." Though disagreement continues about the origin of those sounds, I would like the record to reflect that all who have heard the recording have agreed that they are indeed dead ringers for the "real thing" as best as can be determined, both to the ear and on the sonogram. So it seems that even we Tennesseans with our fallible human ears actually can tell the difference between potential double knocks and the plethora of other possible confusion sounds.

Other posts in this series:

Monday, August 24, 2009

High Water

April 2, 2008


There they went again. Every time the Cornellians let loose with the double knock simulator, the first one always made me jump in the instant before I reminded myself what it really was. At the beginning of the day I found them quite exciting, but by midday I had begun to find them a bit disturbing. They went off every hour on the hour, 7 simulations 10 seconds apart,. After a few cycles of that I started to worry about any real bird that might be in the area -- what would it make of this sudden invasion of double knockers?

The first set I had heard were late, coming at 9:15 instead of the scheduled time. Hence it took until the second or third whack before my pulse slowed back down. The resemblance between the simulated double knocks and what I had actually heard on March 11 was close enough to give me even more reason to get all goose-pimply about that first incident. The simulations were not dead ringers; the "real" sounds I had heard had been notably louder and more resonant -- more boom and less whack, as it were. But it was a pretty good approximation. Assuming that the simulator had been designed by experts to give a reasonable imitation of the real Campephilus double knock, that made the MIMDKWTFII all the more engrossing. Over the course of the day as I heard the simulations at the top of each hour, I also noticed that they were less consistent than the "real" series I had heard on the 11th. The spacing between the knocks was not so precise, and there were some distinct "double klunkers" in the mix where something obviously went wrong with the swing of the striker and the sound that came out was a serious dud.

I had arrived the previous afternoon, laden with gear for three or four nights in the field. The water was much higher than on my last visit, and it took me several hours to shuttle my heap-o-crap from the Great River Road to the barn. The road into the WMA was about 50% flooded, so I alternately pulled my kayak behind me as a barge, then carried all my stuff across the dry stretches, portaged the boat, and repeated the cycle. It took a whole lot of iterations of this before I had tent, sleeping gear, food, water, and boat all transfered the mile from my truck to the camp. A small tent city was already set up in the lawn around the Barn, as the Cornell Crew had arrived the day before (there's a happy group photo at the bottom of the linked page; about half of that crew made the trip to Moss Island). Scott had assured me that on teardown day there would be a john boat and an outboard to shuttle all the gear back out to the levee, so I wouldn't have to repeat the slog. The one remaining glitch was getting my truck to safe parking. By all accounts any vehicle left parked along the levee road overnight would be broken in to and stripped by morning, if it was still even there. So the plan was that at the end of the first day Scott and I would caravan to the motel in Dyersburg where he had home base set up, I'd leave my truck there, and he would give me a ride back to Moss Island the next morning.

After getting camp set up I then headed off in the kayak towards Rhodes Lake. On the way I encountered Allan Mueller who was waiting for Scott, and Scott who was happily floating on the edges of Rhodes Lake. As it got to near 5:00 p.m. Scott and I headed back out the flooded road. I kept finding myself busting my ass to try to keep up with Scott, until I realized he was half my age and a jock and there was no point in even trying! There was only one road anyway, we'd all wind up in the same spot. So it was just hike, wade, hike, wade, repeat, back to the vehicles and onward to the Comfort Inn for an overpriced bed.

This morning, Scott and I had arrived at the Barn around 7:30, and found Tonya waiting for us with marching orders. Unfortunately we were short one radio, so I headed into the swamp incommunicado. I spent the day floating and paddling quietly around Forked and Hushpucket Lakes, racking up huge woodpecker tallies -- 35 Redbellies, 24 Downies, 16 Red-headeds, 7 Hairies, 9 Sapsuckers, 23 Flickers, and an incredible 28 Pileateds. Just one species lacking, sigh. That Pileated total would have to represent damn near theoretical maximum possible density for the species! Whether or not this would be marginal habitat for an Ivorybill, it was clearly core habitat for every other species of woodpecker of the eastern deciduous forest biome. I also tallied "blond bearded guy in canoe" passing within 50 m of me as I sat on stealthy watch twice during the day; this turned out to be Abe.

The areas I was paddling through represented the terrain from which three of our detections of the MIMDKWTFII had emanated. I had not actually entered these woods before. One of my primary objectives for the day (aside from gettin' th' frikkin' bird) was to see these forests up close. The trees were not impressively large, but there was indeed a lot of dead wood. In particular there seemed to be one species that grew tall but not especially straight, with distinctive bark, that tended to have a lot of dead wood near the top. Good spots for making double knocks from, perhaps? I didn't recognize what species of tree this was, however, in its leafless state.

At 5:00, after I had been floating in Forked Lake for several hours, I noticed that there were no 5 p.m. double knock simulations. I took this as a sign that it was time to head in for the day. I paddled along the road to the edge of the swamp, beached my kayak, and hiked back to the barn. I rounded the bend and came in sight of the house and the barn and got very confused.

The Cornell tent city was gone. Approaching moderate freak-out, I continued on down the road. I was relieved to find Tonya, Abe, and Leighton sitting on the back porch of the evacuated house. They explained that Scott had cancelled the next day's field work because of forecasts of severe weather, and the crew was bugging out for Dyersburg for at least the next 36 hours. And, of course, as I had been radio-less they had not been able to tell me this and had to just wait for me to come out of the woods on my own. I just kind of stood there dumbfounded and snarling trying to figure out what the hell I was supposed to do now. Staying there alone for two days with no communication, no vehicle, behind a mile of floodwaters, and no other people within 8 miles of me did not seem tenable. I was also a bit miffed that the plan had been scrubbed because of a FORECAST for possible severe weather. One thing I had learned as a trucker, you don't make plans around weather forecasts more than a few hours in advance. Trying to outsmart the storm was just as likely to land you smack in the middle of it when, as was inevitable, 6 or 12 hours later the forecast shifted. What you did was you made your plan, and you prepared for and responded to the adverse weather when, where, and if it happened. After all it was Tennessee in early April, of COURSE there would be some big thunderstorms around! One might also ponder which was actually safer in a tornado: a tent in an open lawn or a motel in a state without building codes? It was too late then to do anything but gripe about decisions already made (which I did, loudly, to the point that I think the Cornellians might have been getting afraid of me...).

The only course of action was to hurriedly pack up my heap-o-crap and 4 days worth of supplies, slog it all back out to the road, and ride back to Dyersburg with the gang. Fortunately the Cornell crew was well-hardened after a long season in the Big Woods, so they made a very capable tear down crew and team of pack mules to help get all my junk out to the levee in one trip. Only my boat was left behind. I could not see spending the next day and a half in the Comfort Inn, particularly since I was not yet entirely confident that money for reimbursement would really be forthcoming; I'd wound up eating my expenses for the little bit of work I had done on 2007. I decided I'd just head out the next morning, retrieve my boat, and drive home. At least I had one good (if Campephilusless) day in the field to show for my effort, and renewed confidence that we really might not be entirely wasting our time on this quest.

Once in the motel I just wanted to get clean, dry, and calmed down. I headed straight for the shower; on emerging I heard a knock at the door. Pulling on my jeans, I found that Leighton apparently had been picked or volunteered for "go asked the scary pissed-off local guy if he wants to go get dinner" duty. Maybe they figured I'd be less likely to attack a fellow longbeard (cue the music: "There is a brotherhood of beards! A benevolent brotherhood of beards!"). Finding a shirt that did not smell like a wet horse, I decided to join the crew.

Earlier, Tonya and the guys had mentioned to me back at the barn that Scott had a possible encounter he wanted to talk to me about; I hadn't been able to give it much attention in the scramble over what to do with my heap-o-crap. Now, gathered around the table at one of Dyersburg's collection of standard-issue freeway exit chain "family restaurants," one of the first things Scott asked me was "Where were you at 9:18 this morning?" I pointed at Abe and said "On Forked Lake listening to his double knock simulations." Scott and the rest of the crew looked puzzled, because the sims were supposed to have been at 9:00. Abe explained that he had been late because it had taken him a while to find a suitable tree and get set up. Now Scott looked concerned. He had heard a distant but clear double knock at 9:18 by his watch. He had been stationed about 1km west of me, which would have been about 1200m west of Abe, and to him the sound seemed to originate from his south, about 400m away by his estimate.

Now we had a conundrum. Simulations at 9:15 (finishing at 9:16) by my GPS time, versus DK heard at 9:18 by Scott's watch. Both timepieces were in general accurate to within a few seconds of each other, as Scott regularly synchs his watch with his GPS. Sound coming from due east versus from due south. Strange things do happen with perceptions of the directions of sounds. I know in my case, since my right ear still has the hearing it had when I was 18 but my left ear has the hearing of the middle-aged man I actually am, faint sounds can be frustratingly difficult for me to localize unless I get to hear them repeatedly. Scott is still a spring chicken, however, and all my time with him indicated he didn't have any of these hearing problems. Plus, 400m is not all that distant for a sound this loud. Scott was completely confident both in his time stamp and the direction; Abe and I agreed on the start time for his simulations and that it had been the standard series finishing after one minute.

Yet again, what do we make of this? Did Scott hear a response to the simulations? Or did he hear an echo or misjudge the direction by 90 degrees, combined with inaccurate timekeeping on somebody's part? Or was it some other coincidental sound that happened to do a good imitation of a double-knocking woodpecker and happened to come 2-3 minutes after the simulations? If Scott did hear an independent sound, then he did not hear the simulations at all. Would a woodpecker respond to a simulation that is too faint for a human to notice? This is part of the problem with the simulations. Whether or not they have ever triggered a response from an Ivorybill is unknown. But they do complicate the interpretation of sounds that are heard around times when they are being conducted. In theory this can be dealt with by having all field parties in real-time radio contact; in reality finding easily portable field-worthy radios that work reliably through over 1 km of forest without a repeater has proven difficult (perhaps impossible). This is not the last time this issue would come up.

After that discussion I had settled down enough to be sociable. One of the other bits of the conversation from the evening was related by me last year (in somewhat obfuscated terms) in this post. By now it should be clear what birding milestone I would consider having permanently inked into my body. For the record, by the way, I remain ink-free (dammit). The gang hatched a plan for how they were going to spend the forecast rainout; I won't spill the beans on them for fear of damaging their reputations irreparably but it sure as hell was not the sort of thing I was keen on doing. It sounded like they were not planning to get out in the swamp for another day or even two, which confirmed my decision to just go retrieve my boat in the morning, call it a wash, and head home. Which I did.

Rhodes Lake Road

Other posts in this series:

Thursday, August 20, 2009

Irrational Exuberance

The Mass Invasion had only fanned the flames of the frenzy we had already been in. As seems to be the norm, it yielded neither The Prize nor nothing. Scott in particular was trying to make plans like a mad man while also getting more field time in himself. As he put it, it was hard to leave that swamp unattended.

Once again, the Big Question loomed: What the hell is really going on here? We remained at a loss for a simple, ordinary explanation for the double knocks and their pattern of occurrence. And now we had our very own "brief glimpse" sighting to add to the "intriguing audio encounters." Our story was so much like all the others -- Arkansas, Florida, South Carolina, you name it. Our hot zone seemed as hot as any of the others, especially considering our limited person-power and that this had not even been going on for four weeks. In terms of spatial extent, our "detections" (of whatever it was) were even more tightly clustered than was typical, so far spanning only about 1 km from southernmost to northernmost. This raised thoughts that we hesitated to speak out loud.

The wildest possibility, of course, was that we might have stumbled into a nesting territory (of a bird we had not yet even definitely seen...). At the very least it suggested there might be a bird regularly roosting within a quite small area; the one DK heard by Scott and Melinda 20 minutes before sunset sure did suggest this possibility. Leafout was fast approaching; spring migrants were already trickling in and buds were cracking. Scott figured we had two weeks left to get the bird before the canopy closed and the mosquitoes came out. Everyone was pretty hyped up.

Underneath all this exuberance was the constant, droning self-reminder that we did not actually know what we were hearing, we had no definitive evidence of anything, all we had were strange sounds in the woods. I began referring to the object of the quest as the "Moss Island Mystery Double Knocker (Whatever It Is)" which I will abbreviate as MIMDKWTFII from here on. But, given the magnitude of what it would mean if it turned out that our wild hopes were actually true and the MIMDKWTFII really was an Ivorybill, or even a pair of Ivorybills, we felt compelled to act as though this hope were fact. This meant get the bird. Nail that sucker down. Don't let it get away. Never mind that larger crews with far more time to work with had failed repeatedly in the exact same quest in other places. You have to act as though you will be the lucky ones otherwise failure is guaranteed.

Meanwhile, the water continued to rise slowly. It had entered firmly into the zone of maximum inconvenience: too high to drive or hike, but not high enough to avoid cumbersome portages. Scott discovered the full reality of this when it took him two hours each way to get from his truck to Rhodes Lake, paddling, dragging, and portaging. On the plus side, Highway 88 was flooded and closed, meaning no traffic and no truck noises. Plus the turkey hunters were pretty much flooded out of the woods as well, so no gunshots either.

Scott worked out a plan with the Arkansas project for some of their full-time staff to come spend 4 or 5 days at Moss Island, doing things their way. I raised an eyebrow or two at the impression that they were helicoptering in for the glory at the end of the battle, but of course it had much more to do with the fact that we had something (whatever it was) going on while they had pretty much nothing going on in Arkansas. Also, their high water was much harder to work with than ours. Initially Scott and Allan Mueller of the Arkansas Nature Conservancy were going to be the only non-Cornell people on the crew, then it was going to be Allan for half the week and me for the other half of the week, then it wound up being both Allan and me for the whole time, then I'm not sure what the final plan was. I was set to arrive back on site on the afternoon of April Fool's Day.

Other posts in this series:

Monday, August 17, 2009

"Did you hear that?"

Incident at Rhodes Lake

March 21, 2008

For the final big sit this morning, I requested to be somewhere on Rhodes Lake. Though I had been hearing about it for three weeks, I had not yet actually seen this lake. Scott assigned a total of six people in five boats to the Rhodes Lake area -- himself, me, Melinda, and Marty Piorkowski each in individual kayaks, and Dave Pereksta and another Cornell volunteer, Rich, together in a canoe. It was a long paddle out to the lake along the road, with several portages, so we didn't all get on station until around 7:30 a.m. We spaced ourselves out around the lake, with a concentration at the south end near the sill and ATV trail. I was positioned at the east end of the sill; Dave and Rich were at the west end of the sill, and Scott was a short ways northwest of them on a high spot on the road that allowed him to get out of his boat and have more stability for shooting photos. Marty was on the northeastern shore a good ways north of us, and Melinda was roving in the woods between Rhodes Lake and Willow Flat. Each boat around the lake had a radio, but communication didn't always reach between everyone. Meanwhile, a half dozen or more other people who had remained for the second day were scattered elsewhere around the WMA.

As soon as I had reached the lake I realized why it had quickly become a favorite stakeout spot. It provides nice open vistas and good travel lines for sound from forests in every direction; it looked like the perfect place to spot *something* flying over the lake. The weather was fair, but the wind had picked up from the day before. It was blowing almost directly out of the south at about 5 to 10 m.p.h. This isn't terribly strong, but it is enough to begin to have an impact on ear birding. Marty was the most exposed, being in the open on the leeward shore of the lake with a several hundred meter fetch of open water to windward. I was moderately sheltered, tied off to a buttonbush and listening for anything suspicious. Upwind from me was about 300 m of open flooded shrub swamp, a narrowly tapering triangle of widely-spaced buttonbush and swamp privet with much open water extending southeastwards below the sill, bordered by forest on both sides.

As the morning progressed, a notable racket of aggitated Pileated Woodpeckers began from the forest down near the far end of the narrow shrub swamp. From my lookout spot at the west end of the sill, this was almost due south and directly upwind. There was extensive rapping and vocalizing along with some drumming. I could see the occasional bit of movement in the area, all of which proved to be Pileateds. After just over an hour and a half on station, the still-controversial incident happened. My notes read:

"9:05 a.m. Very loud double, [compass] bearing 179, first [rap] clearly much louder. Loudest rap, bang, boom of the morning by far. Not echoing like gunshot."

I immediately called on the radio "Did you hear THAT?" Melinda responded with an emphatic "yes!" as did Scott. Marty sounded dejected and answered that he could not heard anything over the wind. Dave gave a rather non-commital, uncertain response that they had heard something. The sound had come from the same direction as the Pileated ruckus. The quality and timing of the knock was very similar to what I had heard on March 11. My impression initially was that it was not quite so loud, but thinking more about it later, the relative loudness between the double rap and the similarly distant Pileated drumming was comparable in both incidents. The biggest difference was that the second knock this time was much less loud than the first; on the earlier series in each case that I heard them clearly the difference in power between the two knocks was not so great.

I remained on station listening closely, hoping that this would prove to be the beginning of another series. At 9:12 a.m. there was a single rap from the west (not south) that was notable but not nearly as loud as the earlier one. Scott called this single out on the radio; he was probably closer to it than I was. To my ears it was not at all as remarkable as the first one; Scott agreed. A half hour after the double knock, it was clear that whatever I had heard had been a one-time phenomenon, not the start of something grander. I began paddling slowly in the direction from which the knock had come, hearing and seeing nothing noteworthy. Even the Pileated activity had ceased. At about 9:52 I heard some gunshot-like noises from the southeast, and at 9:54 and 9:55 two separate double whomps that sounded like a truck on a bridge, also to the southeast. These bridge whomps were very different in quality than the double rap, sounding more distant and muffled, with both whomps equally loud. The traffic on Highway 88 was audible continuously from that same general direction from south end of the shrub swamp.

As the morning wound down, we reconvened to compare notes yet again. It turned out that only I had heard a double rap; the others had heard only a very loud single rap. Scott and I triangulated the bearings from which the sound had come from our two locations, and mapped the source as having been exactly where it appeared to have been to me: 300m due south of me, at the southeast corner of the shrubby opening. That location by itself would appear to rule out gunshots and mechanical sounds; it would have been hard for a person at that location to not be noticeable, and it was not a distant off-site sound. Looking at our positions revealed an interesting pattern. I had been closest, and directly downwind. I was the only one who heard two raps. Rich, Dave, and Scott had been only slightly farther away, but significantly farther askew from downwind; they heard a loud single rap. Melinda had been about 600-800m away from the source and in the forest, but like me directly downwind; she heard a very distant but very distinct loud single rap. Marty was closer than Melinda (about 500m) but also off the wind direction and fully exposed on the lee shore of the lake; he heard nothing.

Scott and Melinda both felt the quality of the knock was consistent with the double knocks they had heard in February, but without the second rap. The Cornell canoe had different opinions. Dave remained very non-commital and hesitant; when I had the chance to ask him about it privately much later he said that he had not felt that he was really keyed in to the sound and was uncomfortable saying much other than that he had only picked up one bam, not two. Rich was much more adamant. He was insistent that the sound could not have been a double knock and could not have been a bird. He thought it was some loud mechanical sound from a mile off site; when we pointed out the triangulation indicating that it had in fact been just a few hundred meters from him and indubitably on-site in the flooded forest he suggested that it must have been some human noise like someone ramming a boat into a tree. I pointed out that I we knew where all of our crew were, no one had been near that location, and there had been no sign of any other boaters near there or anywhere else in the WMA that morning. Still, he was having none of it and was as certain that there could not possibly have been a second rap as I was certain that I had definitely and distinctly heard a second rap. The contrast between his certainty and Dave's hesitance was interesting.

Disagreements would just have to remain unresolved, as it was time for everyone to pack up and head home. The Mass Invasion had only added to the mystery and confusion about what, if anything, was going on in that swamp.

Looking south from my station across the inundated shrub swamp below Rhodes Lake

Other posts in this series:

Friday, August 14, 2009

Ghostly White

Mass Invasion, day 1

March 20, 2008

Another beautiful morning in the swamp. The water levels were up several more feet from my first visit, but this time I had my kayak. I hadn't been able to find the right paddles, however, so I was making do with an improvised contraption (that could be straight from the Red Green Show) involving two ordinary paddles, a piece of PVC, and some duct tape. I was working my way along a grand irregular loop through the northwest corner of the forested part of Moss Island. Paddling through flooded forest has its challenges, the first of which is that the forest floor floats. So, you may be hovering a meter or two above the ground, but so are all the logs. It makes for a lot of zig-zagging and strategizing.

The birds were out in force on this crisp, sunny, calm morning. Woodpeckers of seven species were drumming, vocalizing, and putting in appearances everywhere. The Wood Ducks were in full hormonal rush as well; several times I saw a peculiar flapping in the canopy, finding that it was a Wood Duck straddling the entrance to a cavity, bracing with its tail woodpecker-style, and flailing its wings slowly in the air as if for balance. The forest floor birds were out also. They were foraging around in the floating mats of logs, twigs, and dead leaves, gleaning for food exactly as they would have been doing had this debris still been resting on dry ground.

There were something on the order of 20 other observers spread out through the woods along with me, some on foot, some in boats. Four Cornell volunteers and their crew boss, Marty Piorkowski, were camped out on site around The Barn, as was I. Scott was joined on the forces in uniform by about a half dozen other folks from TWRA and FWS. All these official sorts were complemented by a gang of assorted experienced birders from middle and west Tennessee that Scott had invited along. This crew included quite a few very well respected birders; I thought it spoke well of the regard they must have for Scott hat they would take time off from work and make the long drive to Dyer County to help him on this insane mission!

Scott had parceled out his crew in an effort to spread people over the whole WMA, with a somewhat heavier concentration in the putative "hot zone" around Rhodes, Hushpucket, and Forked Lakes. As many people as possible were camera equiped, just in case. It was a bit daunting to realize that even with a crew this big, and in an area this small, we were still nowhere near saturation coverage. Large areas of forest remained many hundreds of meters away from any observer. Still, the weather was ideal, and our detection rate over the last few weeks seemed to give us good odds that somebody would find something. The plan was for us all to reconvene at lunchtime, compare notes, and redeploy for the afternoon.

The corner of the WMA that I was covering, what I would come to call the "northwest woods," was almost terra incognita to us of the "official search." The far northwest corner of the WMA is situated on yet another oxbow lake, Mitchell Lake. The USGS topo indicated that it was the only open water in this vicinity. I quickly discovered that things were more complicated than this. It turns out that since the topo was last updated, two more lakes have opened in the same neighborhood. One of these I figured out was the feature I had heard called "Cocklebur Flat," and had evidently been the scene of one of the strange woodpecker flyovers reported by the TWRA staff sometime in the previous year or so. The second is a large, handsome lake surrounded by good hardwood forest that seems to have no name at all. I eventually began calling it "Flycatcher Lake" for my own purposes, after the day in May when I was alternately serenaded by Olive-sided and Willow Flycatchers as I floated there. So much territory, so many lakes, so many trees, so many places to hide, even in just this one small forest fragment.

My long paddle around all these mystery lakes yielded a heap of woodpeckers, but nothing beyond the expected seven species. My morning's tallies were 8 Hairies, 22 Downies, 37 Redbellies, 13 Pileateds, 8 Sapsuckers, 12 Flickers, and one sole Red-headed. I returned for the lunchtime rendezvous, hoping for big news from someone. But, one by one each crew returned with nothing to report. Not nothing, really; lots of birds had been seen. Dave Pereksta, one of the Cornell volunteers and a FWS biologist in southern California, had found an extremely early Kentucky Warbler; his photo of this bird wound up gracing the regional report in North American Birds. But no double knocks, no sightings, no kents, no sign of the target bird. After lunch, during which we admired a squadron of White Pelicans overhead, our assignments were all reshuffled and we headed back out. I returned to the scene of my first crime again, a long sit near Hushpucket Lake. In contrast to the morning, the afternoon was very quiet. Woodpecker activity was a small fraction of what it had been earlier in the day. After the long slow sit, we reconvened again to trade stories.

Dave Pereksta had that look. He had seen a ghost. Not much, just a glimpse, a tale that had become far too familiar in recent years. While traversing the flooded ATV trail from Rhodes Lake towards Willow Flat, a big woodpecker flushed and flew rapidly across the trail ahead of him, disappearing into the forest not to be seen again. He hadn't seen much, couldn't give a whole lot of details, but he seemed pretty certain that he had seen the bird flash too much white, and in the wrong places. He did not seem to be disseminating this tale too widely, so this might be news to some who read this who were actually there on that day. Scott asked me quietly what I thought of Dave's sighting, and I couldn't do much more than shrug. Dave is a well known and respected SoCal birder, as well as a veteran of multiple tours of duty with Cornell in Arkansas. He had some audio encounters in Arkansas the first search year that had been taken seriously by the Cornell crew. But, a brief glimpse without definitive field marks remains just that no matter who it is from; another piece of intriguing information that stimulates interest and enthusiasm but establishes nothing definite. Other than Dave's sighting, there was nothing else reported for the day.

Some folks headed to Dyersburg for hotel rooms, some headed home, and Scott, the Cornell crew, and I returned to our camp at the barn. Tomorrow morning we'd do one more deployment with those who remained.

Scott in his kayak, the Tropical Fish. He painted it forest green shortly after this photo.

Other posts in this series:

Thursday, August 13, 2009

Moss Island Geography

At this point I should give a better overview of the geography of the places I'll be talking about in the coming weeks. This is an "extra" post; I plan on the posting the next regular installment tomorrow. I've put together a labeled aerial photo of the site, showing the roads, trails, and place names (click for 1.0MB larger version):

Place names in quotes are just casual names that we use amongst ourselves; they'd not likely be recognized by the longer-term managers, visitors, and residents. I've also made a cropped version of the scanned USGS topo map of the site (click for 956KB larger version):

Some of the more important features:

"The Barn." This is really more of a shed, though it is always called the barn. It sits atop a suspicious mound of dirt that to my untrained eyes kind of resembles a Native American trash heap. Whatever its origin, this hill keeps the barn above floodwaters. It is a frequent rendezvous and camping spot, plus a place to store boats and other gear. For the 2009 season I just set up my tent in the barn permanently.

The lakes. There are quite a few of these, apparently an increasing number over the decades. The USGS map only shows the four named ones (Mitchell, Rhodes, Forked, and Hushpucket) as open water. The aerial photo reveals something more like the present-day situation, with large lakes having apparently recently opened along Willow Flat, Cocklebur Flat, and between Mitchell Lake and Cocklebur Flat. This last lake is now comparable in size to Rhodes Lake, formerly the largest lake on site; the lake now occupying Willow Flat in terms of surface area exceeds both of them. I have never been able to find anyone who knows a generally accepted name for the large lake southeast of Mitchell Lake; I have started calling it "Flycatcher Lake" after the May day when I was floating there on watch and was serenaded by Olive-sided and Willow Flycatchers. It may not have a name, but duck hunters still know about it and regularly access it from the Obion. As to why these lakes have opened up, the only theory I have heard advanced is that increased beaver activity has raised their summertime water levels and killed off the trees. Willow Flat Lake in particular appears to still be growing; there are many recent snags in it, and its northwestern end is a boneyard of dead and dying trees.

The trails. I have mapped the ATV trails as though they are well-defined. In many cases this is not true. A majority of the complex of trails shown in the area just west of Rhodes Lake are more like traces of former trails. Of the well-defined ones, three are the most important:

1. The trail from the end of Rhodes Lake Road across the east end of Rhodes Lake to Willow Flat. This runs along the structure built at the downstream end of Rhodes Lake to stabilize its water level. This structure has been often called the "levee," but technically I think it is more properly called a "sill." It provides a good vantage point for listening and watching; several of the early double knock incidents happened at or near this spot. It also provides access for fishermen and hunters to haul boats to the put-in on Willow Flat at its eastern terminus.

2. The "Canoe Trail" that runs from the Barn almost due eastward to the northern parts of Willow Flat. It is really an ATV trail, but early in our adventures it was usually flooded so Scott dubbed it the canoe trail and the name stuck. It traverses some of the better hardwood forest habitat at Moss Island, and generally yields large numbers and diversity of woodpeckers and other forest birds.

3. The trail that runs south from Rhodes Lake Road just west of the turnaround. Another area of nice hardwood habitat and high woodpecker abundances. This is the trail I intercepted about 9 a.m. on 3/11/08, and from which I heard the first double knock of the series on that morning. It kind of fades out nowhere in particular near but not quite at the southern edge of the forest.

The fields. The central fields seem fairly stable over the long-term; most are cultivated. The south fields are shown as forest in the USGS map before they were acquired by the state and added to the WMA. They are now being reforested, having been planted with native hardwoods beginning in 2007. One of the technicians planting these trees was the source of one of the early TWRA encounters, a strange woodpecker seen and heard along the south edge of the forest here. The fields themselves are of course not woodpecker habitat, but they provide a vantage point and travel corridor along the edge of these road- and trail-less woods. They also can provide excellent birding for oldfield passerines and wetland birds.

Other posts in this series:

Tuesday, August 11, 2009


This is your brain on Ivorybills

On my return home on March 12, the first order of business was to flesh out my "official" account of the Bambam Incident before I read or listened to anything else. I had scribbled some quickies in the field at the time, and written up the incident in my field notebook at greater length later that same day, so it was mostly a matter of adding grammar, punctuation, context, locations, etc. I won't reproduce the writeup verbatim here, as it has been pretty thoroughly paraphrased and quoted in my previous post.

With that out of the way, I felt free to start listening to recordings and reading historical accounts. In terms of quality, rhythm, etc., recorded double knocks of Pale-billed Woodpeckers were awfully freekin' close to what I heard, if one were to put them through a massive mega amplifier. Contemporary descriptions by early 20th Century observers of Ivorybill double knocks were also sometimes uncannily accurate descriptions of the sounds from my 21st Century encounter. Loud, very loud, unexpectedly loud, everyone stressed this. I had a spine-chilling, we're-not-in-Kansas-anymore moment when I read this quote from Don Eckleberry, describing an encounter with a female Ivorybill in Louisiana:

With a few disordered feathers properly and vigorously rearranged, she gave her distinctive double rap, the second blow following so closely on the first that it was almost like an echo--an astonishingly loud, hollow, drumlike Bam-am!

In my own writeup I had describe the loudness of what I heard as "astounding" rather than "astonishing," and I had used a "b" where he used a hyphen in the onomatopoetic spelling of the sound. Other than that...

But what to make of this? Obviously some banging sounds in the woods do not an Ivory-billed Woodpecker make. We were not in any position to make any firm declaration about what the source of these noises was. But we could ponder, speculate, and infer. One thing seemed clear: the source of the noises was biological. They were heard in calm and near-calm winds, repeatedly within the same general area but not at the exact same spot, and they seemed to all be nearly identical. What else is going to do this but a mobile biological source? But.. WHAT biological source? The one critter that has been documented making a very similar sound is (at best) one of the rarest organisms on the continent, and this scraggly forest is hardly the right habitat for it.

Hold on, let's revisit that last statement. Do we really know what habitats a relict surviving Ivorybill would be using now in this century? This has of course been the subject of much debate. We have a modest amount of information about 19th and early 20th Century habitat usage; and that actually points to a moderate amount of plasticity: bottomlands, pines, virgin growth, cutover stands. But even if the species was restricted to old-growth bottomland hardwoods 70 years ago, are there strong reasons to conclude that any possible surviving birds would still be restricted to this habitat or its close approximations? Well, actually, no.

Many forest birds have modified their habitat usage in recent decades and centuries. Chimney Swifts are an obvious example; also quite telling is the Vaux's Swift which has only begun moving out of old growth and into chimneys in the last few decades. But of more direct relevance, consider the following quotes:

When found they are usually in regions of original forest growth, rarely being seen where the woods have been once cut over. [...] As this Woodpecker seems not to possess the faculty of adapting itself to the new conditions created by civilization, it is quite possible that it will not long survive the passing of our primeval forests. T. Gilbert Pearson, Birds of America, 1936.
Its presence in a region is more often revealed by the large cavities it excavates in dead stumps and trunks than by actual observation of the bird itself. [...] This species is common only in the wilder parts of its range. Frank M. Chapman, Handbook of Birds of Eastern North America, 1939.

Both of these early 20th Century characterizations are of the habitat requirements of the Pileated Woodpecker. In fact, as we all know, over the intervening decades Pileateds managed to adapt to forest fragmentation and second growth quite well, thank you, and are now widespread in habitats well beyond the range of what was described in the 1930s.

There's also another fundamental, perhaps somewhat tautological factor at work. If in fact Ivorybills were an obligate old-growth bird, then yes, they are now extinct. If they were never able to utilize second growth and fragmented forest, then there is absolutely no reason to be looking for them now anywhere. But even given the historical accounts of their habits they demonstrated a bit more flexibility than this; and given the actual history of Pileateds and various other forest birds since the industrial revolution, it seems brash and unjustified to presume that the habitat utilization of a 21st Century Ivorybill would be the same as that of one in the 19th Century.

All these intellectual ponderings are fascinating and intriguing, but more urgently we were in something of a campephilitic frenzy. On March 13th Bob heard another double knock near Forked Lake, another oxbow lake situated midway between Hushpucket and Rhodes Lakes. As an interesting linguistic side note, "Forked" in place names in this area is pronounced with two syllables, King James style. We all felt we had to strike while the zone was hot and before the leaves closed the canopy in and cut off sight lines. Rapid response took priority over full analysis of what we had; there'd be much more time for debate and discussion later. Scott was making arrangements for a mass invasion, an effort to get as many people as practical out in the WMA at the same time for a couple of days. Cornell was offering the loan of their Arkansas volunteer crew for a few days. TWRA, the Feds, and selected invited guests were set to rendezvous at Moss Island on March 20-21.

Other posts in this series:

Friday, August 07, 2009

Posting schedule

For the two or three of you out there who might be following my Moss Island tale (and why is the Department of Justice checking out my blog??? Scary things you discover when you look too closely at your stats from Sitemeter), I am going to try to stick to a Tuesday and Friday posting schedule. The next post might be a little late, however, as we have company coming for a few days. Once a week would take a very long time to finish the story, but daily would be faster than I could write, so twice a week seems to be the compromise.

Down the Rabbit Hole

But I don't want to go among mad people...

March 11, 2008

The problem with staying in Dyersburg, other than the hotel cost, is the nearly one hour drive to get to Moss Island. By the time we were in the field and ready to deploy, it was well after 7 a.m. Scott and Melinda headed off in the canoe as previously planned. I set out overland on foot along the ridge trending south from the point where the road met the water, the place which became known as "the turnaround." For a while I could hear the other two chatting and working their way off through the sloughs; gradually we fell out of easy hearing range of each other. It was a picture postcard late winter morning, with clear skies, cool but above freezing, and a near calm wind, drifting almost imperceptibly from the south and east. As I worked my way generally towards the south I stopped and sat several times along the shore of a very pretty flooded slough that lay just east of the ridge I was traversing. The ridge itself was more of a broad flat plateau. In some places the understory was very open, in others there were thick canebrakes.

At around 9 a.m I intersected an ATV trail adjacent to a shallow, minor slough. The scribbled comment in my notebook gives the Lat-Long and reads "Slough - nice, much woodpecker activity." There had been a good deal of drumming and vocalizing from the woodpeckers all morning; at this point in the journey it picked up even more. On my one visit to the Big Woods in Arkansas a couple of years before, the thing that had struck me most (after the size of the trees) was the incredibly high abundance of all species of woodpeckers. Ever since then, I have always taken particular and hopeful note of times and places where I encounter similar woodpecker hotbeds. The ATV trail was going more or less my way, as I had no particular destination or route in mind, and I began following it.

The trail meandered south-southeasterly, pulled away from the slough, and rose slightly into an open canebrake. At this point I barely registered a loud banging sound in the distance to the southeast. At first I did not really key in to it, as there had been frequent noise from distant gunshots, bridge whumps, barge sounds, and the like off to the west. It did not at first jump above the background of bangs. A few minutes later it repeated, and that time it pulled me up to a stop and caught my attention as a loud double "bam" sound. It gave the impression of being very loud, and very distant. I thought it a bit curious, not much more than that. However, I considered that I was supposed to be out here listening for double knocks, and that had been some kind of double banging sound, so I gave my attention to it. It seemed much louder than I would have expected any possible woodpecker noise to be, but I still decided I should hear it better. I left the ATV trail and headed southeasterly overland in the general direction of the sound. In a few minutes I heard it again, clearly and with my full attention this time.

What I heard was two very loud, closely-spaced "bam" sounds, the first "bam" loudest, the second following quite closely after the first. My curiosity was definitely tweeked, as this is of course the classic Campephilus pattern. Still, though, it was so very loud, unreasonably loud to be from a bird. I continued towards the sound trying to be as quiet as possible, hearing it maybe two or three more times as I travelled. I was not yet taking it seriously enough to be noting exact times and locations of each recurrence; I expected it would probably turn out to be some off-site mechanical sound, perhaps construction or farm noise. In one instance I heard only one single "bam," but all the other occasions seemed identical in cadence: two bams, consistent close spacing in time, first notably louder than the second. Each pair was separated from the others by several minutes.

My efforts at stealth were spoiled by a flock of 50 or more turkeys in my path, who began running and flushing and calling loudly ahead of me. Shortly past the turkeys, I came upon the head of a lake and realized the "bam" sounds were coming from the far side. There appeared to be no way across or around the lake, so I just sat on the west shore right at the northern end of the lake, watching and listening. Within a few minutes the "BAMbam" sounded again, across the lake, to my southeast. I had apparently covered a good deal of the distance between myself and the source as it now sounded much louder and much nearer than it had at first, but it remained beyond the far shore, perhaps 200 meters or more from me. At this point strange things began happening in my head. There was a Pileated drumming a bit farther south along the far lakeshore. The quality of the Pileated raps, and the way it echoed, were very similar to the individual bams in the BAMbam. But the BAMbam was much, much louder. My scribbled note made while I sat there reads "Phenomenally loud." Two woodpecker-like raps, very closely spaced, first rap loudest, preternaturally loud... um... uh... knot begins to form in stomach. Jeeezus frikkin' Kryst is THAT the double knock everyone has been going on and on about for all these years?

On schedule, a few minutes later, it rang out again. I took in all the sounds that were coming from across the lake. There were the usual bird sounds, two Pileateds drumming back and forth at each other, the murmurings of the turkeys. I strained to hear if there were any clearly man-made sounds, anything suggestive of a boat, a construction site, voices, motors, doors, squeaks, anything. There was nothing. It sounded like a flooded, unpeopled wilderness over there. And again, one more time, came the BAMbam, ringing like an axe striking a tree, or like a 2x4 tossed from a truck onto a sheet of plywood, the loudest sound in the woods, consistent to the point of being nearly identical each time. It wasn't a bridge whump. It wasn't a gunshot. It wasn't a boat ramming a tree, unless it managed to do it exactly the same way every time, in the exact same place, without making any other noises in the interludes. From how far I had travelled since the first hearing (maybe 500m) and how much closer it seemed now, there didn't appear to be any way for it to be a distant off-site noise. Here from the lakeshore the sound was clear, crisp, clean, not muffled or muddied by traveling and reverberating through a kilometer or more of forest.

Somewhere between the second and third BAMbams I heard from the lakeshore, the freakout happened. I allowed the thought that I might conceivably, possibly, at that very moment, in the 21st Century, be sitting only a few hundred meters away from a real, live, flesh and blood Ivory-billed Woodpecker. Staring across the water into that patch of forest, contemplating that this legendary beast might actually be perched just out of view, just there, just across that lake, was a sensation that is difficult to describe. It was otherworldly, exhilarating, and disorienting; it was also tinged with a strong dose of fear and the sensation of "Oh sh*t, I am in trouble now." There was rather a significant voice in the back of my head saying "Maybe we shouldn't even tell anyone about this; do we really want to deal with the repercussions of that?" Of course, I had been called in to the project in the hope that I might have just such an experience, and report back on it in full, so tempting though it may have been, this last option should not really be on the table.

After the third set of BAMbams heard from the lake, I worked my way south along the shore, hoping to get closer to the source and possibly get a second bearing to triangulate the location. However, I did not hear any more. Whatever the source was, it had stopped entirely. There was not even a hint of anything more from that direction; nor was there any hint of any human-caused sounds either. I remained along the lakeshore for about another hour, by which time it was nearing 11 a.m. We had a scheduled lunch rendezvous back at the turnaround, so I began the hike out. On the way I had plenty of time to review, relive, reconsider, and reevaluate what I had heard.

To my surprise, a big part of me rather strongly hoped to find an easy alternative explanation. What kept running through my head was that if I couldn't explain this away, I was about to become One Of Them -- the people who have had an encounter with something they think may have potentially been an Ivorybill, but are utterly incapable of proving it. The thought of how much easier it would be to just forget all about it and come out of the woods saying "nope, nothing to report" also continued trying to resurface. Those that read this who believe that anyone who could think that this bird could possibly still exist is just a ridiculous, unscientific fool might find this next thought oddly contradictory; but in the end I let the empirical scientist win out, accepted I had heard something that I had no ready explanation for, and I would report exactly what I had heard as best as I was able to document something for which no corroborating evidence existed.

On my hike back, two particular things concerned me the most. The loudness of the bams remained disconcerting to me. It was hard to believe that a bird was making such a huge sound. As I said to Scott and Melinda later, birds are made of fluff and air, how could one possibly make such an enormous noise? I also remained worried that I might have simply heard some mechanical noise from beyond the site, in spite of all the evidence to the contrary. I only had my recollections of the map; I had not packed the map with me. I reached the road and the turnaround, and waited for Scott and Melinda to return from their mission. They arrived a little after noon; I of course immediately asked them if they had heard anything; they answered that they had not. I replied, "We need to have a long talk, because I did."

I described what I had heard, and they reconstructed that during the period I was hearing the "bams" (which lasted for about a half hour) they had been at Rhodes Lake, listening carefully much of the time. We checked the maps, and determined that my listening post had been at the north end of Hushpucket Lake, a wonderfully lyrical name. From there the closest spot from which the sounds could have come if they were from machinery or construction was just across the Obion on a small dead-end road. This was over a kilometer from my location on the lakeshore. If the sound had originated there, Scott and Melinda would have been about the same distance from it as I was. If this had been the case, it was hard to imagine that they could have failed to hear it at all considering that it was very loud and very obvious from my location. I also found it hard to believe that what I had heard had been that far away, considering how crisp it was. The echo from the mystery BAMbams was short, as I mentioned earlier quite similar to the echo from Pileated drumming that was coming from just across the lake in a similar direction. It was not a long, trailing echo such as from a gunshot a mile or two away. This still left the concern over whether a bird could realistically make a sound that loud. Scott and Melinda reminded me that Tanner had reported that Ivorybill double knocks could be heard for over 1/2 mile (800m) under ideal circumstances, and circumstances that morning had been very close to ideal. Scott told me that the double knocks he had heard in the site in the previous weeks had seemed much louder than Pileated drumming to him; he described the one he heard at close range as about the loudest thing he had ever heard in the woods. Looking at the maps we also noted that one double knock that Scott and Melinda had heard together from Rhodes Lake was coming from the same part of the forest as the sounds I had just heard.

After that discussion, I decided I should probably not consult any other descriptions, recordings, or references until after I wrote a full report. It did seem clear, though, that what I had heard was very similar in quality and magnitude to the sounds that had been heard three times previously within the same small area during the previous two weeks by Scott, Melinda, and Bob.

We all three returned to the Scene of the Crime on Hushpucket Lake that afternoon, and again the following morning. We sat, we listened, we watched, we waited. But what I would eventually come to call the Moss Island Mystery Double Knocker failed to put in another performance. On the afternoon of March 12th, I headed home while we all continued to ponder what it all meant and what to do next.

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Tuesday, August 04, 2009

Down to the Delta

Go west, young man, and seek your woodpecker!

March 10, 2008

Green Frog, Maury City, Bells, Halls, Frog Jump ... this was not a part of Tennessee I was at all familiar with. Other than the freeways, my only prior experience in northwest Tennessee consisted of my Breeding Bird Survey route up near Reelfoot Lake. That had been enough, though, to let me know this was a very different world than the Hill-'n'-Holler country where we live. My home county is dissected plateaus, forests, ravines, steep slopes, streams with sparkling clear water over rock and cobble beds. This was flat, vast open fields broken by wooded riparian corridors and windbreaks, and in summer hot, steamy, and buggy. I had learned that biogeographically it is also a strange place. Warbling Vireos, Tree Swallows, and Baltimore Orioles nesting among baldcypress was not a combination that made sense to me. On my current journey it was winter, and the gently rolling fields had a decidedly midwestern feel to them. I could easily imagine I was back in eastern Colorado if I didn't look too closely, especially if I didn't focus on the western horizon where the absence of the Rocky Mountains was rather a giveaway.

Beyond Frog Jump was Porter Gap, which indeed was a gap in the traditional Appalachian sense, but on a smaller scale. Cresting the rise at the west edge of the Chickasaw Bluffs, I looked out over the Mississippi Alluvial Valley, colloquially called "the Delta" even this far north, stretched out about 100 feet below me and seemingly flat as the surface of the sea. It was almost as wet as the surface of the sea as well. The Mississippi had been rising steadily, backing up the tributaries and turning the fallow fields into sprawling shallow lakes. After descending the bluff, the state highway effectively became a causeway, with the wind-tossled floodwaters lapping right at the shoulder of the road on both sides in some spots, only a few feet below the pavement. Where the flood had not yet claimed the entire area of some fields, huge flocks of blackbirds swarmed along the diminishing shoreline, presumably feeding on all manner of critters that had been pushed out by the rising water. If I had bothered to stop and make estimates I likely would have set new personal high counts for some species.

I didn't stop, however. The whole scene had put me in a very strange frame of mind. The reason I was making this trip was peculiar enough -- looking for Ivory-billed Woodpeckers? In Tennessee? Get serious, bro! The unfamiliar and somewhat disorienting countryside, combined with a foreboding flat gray sky, added to the rather unreal sense of it all. But the strongest trigger had been the water. If you're an old-time swamper, like me, then rising water just gets your blood pumping and your mind racing. It becomes instinctive, a conditioned reflex. Anything can happen when the water starts climbing. It's both exciting and intimidating. And... I didn't have my boat. Scott had suggested that there was not likely to be a real need for it, so it was still back at home ditched in the weeds on the shore of the pond. Not only was I traveling into unknown country on a ridiculous quest in the face of rising floodwaters, I was also not properly equipped. Nothing to do about that now.

Back to my driving directions. From here it was north on Great River Road, and about three miles to the entrance to the site. Crossing over the Obion River and then landing on the Mississippi River Levee, I pondered then as I still ponder now: What is the point of a huge levee fortification along the Mississippi that just ends like this at the mouth of the Obion? Wouldn't seem to provide much impediment to the movement of floodwaters in either direction. As directed, I turned east off the levee down the fairly good-condition gravel road, continued a bit to the edge of the woods, and found the sign: Moss Island Wildlife Management Area. Judging from the old, faded, and beaten condition of the sign, this was not one of the flagship units of the Tennessee Wildlife Resource Agency's network of WMAs. The fact that the sign was not visible until after you had already turned off Great River Road and travelled several hundred yards into the backwoods also suggested this was not a place that was a great draw for visitors from beyond the immediate area.

How we wound up here was the usual long story, involving the traditional mix of strange and inconclusive tales from locals and TWRA staff. As I haven't cleared the names and details with all involved I won't go in to them here. What really set off the search was that two day period in late February when Scott finally had an opportunity to check out the place, starting a flurry of "detections" in a short time and a small area. On the face of it, this spot does not seem a likely candidate. In my own surveys of aerial photos across the southeast, I had passed off all of the delta region of Tennessee as too fragmented to warrant much attention. Moss Island was just another one of these fragments, and not even especially impressive or large within that context. As I drove down the main road what I saw seemed to confirm my remotely-sensed impression On my left was pretty but unremarkable bottomland forest (flooded, I noted with a twinge of anxiety... why hadn't I brought the boat?), on the right were fields that still remained high and dry. Well at least Moss Island was indeed a bit of an island; you learn quickly in the swamp world, though, that "island" means "doesn't flood quite as often." It does not mean "dry land."

Scott's directions were to head to the end of the road at the turnaround at Rhodes Lake, and wait. In the initial work done so far, that was the "hot zone." It was now early afternoon; he and Melinda would be meeting me at around 5:00 p.m. I continued in, past the the house where the island's entire permanent resident population (one family, four people, variable numbers of dogs, cats, and chickens) resides, and through more fields, now on both sides of the road. A buteo flying low over the fields to my right caught my eye -- long-wings, languid flight, check that one out. It perched atop an old pecan tree in the fields, I got my optics on it -- yes, Rough-legged Hawk! A first for my sadly neglected Tennessee list, and a bird that has always thrilled me, even in our Colorado days when they were a common winter sight. As pleased as I was to see this handsome creature, it also added to the "where am I and what am I doing here?" sense of the expedition. Seriously, when you are looking for Ivorybill habitat, a Roughleg does not seem like a promising sign. Talk about species with antipodal habitat requirements!

But then, another few hundred yards down the road, that biogeographic hash that is west Tennessee worked its tricks. I dropped down a small slope, entered the forest, and suddenly I was in the swamps of the Deep South. The road was lined with canebreaks, the leafless oaks, sweetgums, maples, and other hardwoods were not huge but they were not shabby, and my swamper soul was right at home. Later I would learn that right near where I had spotted the Roughleg, a few days before Bob Ford had spotted a Common Ground-Dove. I was beginning to figure out that when you are here on the western fringe of the state, you should pretty much be prepared for anything.

Now that I was back in my old familiar world, in a swamp with the river rising, I was not at all surprised when the road disappeared under the water before I reached the designated rendezvous spot. There was a white pickup with Federal plates parked in a pullout just before the water, which I guessed was probably Bob's. Well I had at least brought chest waders, if I didn't have a boat. I suited up and started slogging onward into the swamp. By this time the sky had mostly cleared, the wind had subsided, and the bird activity was picking up. One of the things about these swamps is that, especially in winter, they really don't have a particularly birder-tempting avifauna The most common species are things like Tufted Titmouse, Northern Cardinal, Carolina Wren, and Red-bellied Woodpecker -- species you can find easily in the average suburban backyard. It's not a place for a twitcher. As a consequence, of course, birders spend disproportionately little time in these habitats. Swamping is really more a total environmental experience than a birding trip.

My slog was cut short fairly quickly. Even with chesters, I was dangerously close to topping my waders just a little ways farther down the road, long before reaching Rhodes Lake. It seemed my afternoon of sitting and watching would happen back at the edge of the water near my truck. So back I went, encountering Bob on my way. He had a boat, clever fellow, and was wrapping up his day. He filled me in on the latest news, headed out, and I had the WMA to myself. This left me a couple of hours to sit, listen, and ponder what on earth I was doing here.

Double knocks. That was the main thing that had been found here, and in many other places. I had never quite gotten this "double knock" thing. I had heard the recordings, and read the discussions, but it seemed like such a non-specific sort of sound. I hadn't had the opportunity to hear other Campephilus species' double knocks in person, so I didn't really know first hand; but it just seemed, like cavities and foraging sign, to be a tenuous and vague thing. Listening to the woods around me, I heard all sorts of knocks, bangs, and bumps. Some were animals, some were plants, some were trucks going over the bridges on the adjacent highways making rhythmic "whump-whumps" on the expansion joints, some were the loud bangs and clanks and whams from the barge loading and unloading facilities a few miles farther west along the Mississippi, some were the inevitable and ubiquitous gunshots that never seemed to stop in the rural South no matter what was going on with hunting seasons. How the hell would you single out a "double knock" from this racket?

As dusk was nearing, Scott arrived and we finally met face-to-face for the first time. I think he must have been warned that I was not a typical looking birder, as he seemed unphased by my two feet each of hair and beard. Well, actually, his first words were "Holy crap!" but that was directed at the water level rather than at my hirsuteness. Melinda arrived shortly afterwards, and was equally shocked by the lake where the road had once been. These were my first clues that my co-searchers were not old-time swampers (not yet, at least; they'd earn their credential pretty fast in the coming weeks). I looked at the conspicuous line on the trees marking the typical annual high water mark, and it was still above my head. I looked at the water several meters below this line, and wondered what the fuss was about. We had a long way to go before this would rate as a significant flood. It turns out that though Scott and Melinda had been working in the bottomlands along the Mississippi for two seasons, and Melinda had done a stint in Arkansas with the Cornell project, they had been doing so during a severe drought. They had no image in their heads of how a more typical hydrograph translated into what the real world would look like, and were a tad dumbfounded when confronted with it. Lacking this experience or these instincts, they had installed reconyx cameras and autonomous sound recording units on trees way below that high-water line of demarcation on the trunks. An urgent rescue mission was planned for the next morning.

Scott supplied me with maps, and went over them with me summarizing the area and the activity. Moss Island is situated in a large rightward bend of the Obion River, just above its confluence with the Mississippi. The WMA is roughly circular, containing a large reversed "C" of forest abutting the Obion, with a finger of open fields intruding in the central area and large open parcels on the south. The entire area is only a few kilometers across; all told there might be 5 or 10 km2 of forest. The areas closer to the Obion consist of ridge and swale topography in long sweeping arcs paralleling the river with quite a number of oxbow lakes. Farther west is higher terrace physiography; that is "Moss Island" proper. Our current parking spot was, of course, where the terrace drops off into the swales; hence the deep water just to our east. There was only this one passable road through the forest, jaggedly bisecting the backwards "C" from west to east and terminating at Rhodes Lake. Other than that it was ATV trails -- unmaintained, unmapped, and often indistinct -- and trackless wilderness. We went over where the observers had been standing during each incident, and the estimated distances and directions of what had been heard. It sure did look like whatever it was, it was clustered pretty tightly in the Rhodes Lake area.

After we watched and listened to the swamp growing dark, Scott led the way to the Comfort Inn in Dyersburg, which had become headquarters for the nascent expedition. Tomorrow Scott and Melinda were planning to head out via canoe to rescue the equipment; I would figure out somewhere that I could explore on foot, given that the previous "hot zone" was inundated.

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