Monday, September 28, 2009

Dead of Winter, Ghosts Included

This was proving to be the first real winter that much of Tennessee had experienced in several years. A steady chain of storms kept me away from Moss Island for the rest of January and into early February. On January 28th an ice storm of legendary magnitude encrusted a swath from Arkansas into Kentucky with 1 to 3 inches of freezing rain. This caught the northwest corner of Tennessee, demolishing most of the power distribution grid in Dyer, Lake, and Obion counties. Moss Island received just a glancing blow; there were a lot of branches and a few trees down, but in comparison to what happened just a few miles farther north it looked untouched. As I would find later in the year, from Dyersburg north the tree damage was reminiscent of what we saw on the upper coast of South Carolina in the aftermath of Hurricane Hugo. The big difference was that the ice storm dropped everything straight down rather than pointing uniformly to the northwest. But the overall impact was similar, near total stripping of all small to medium sized branches on most trees, with many topped or felled completely. The Great Ice Storm of '09 will be talked of for generations to come in these areas, I am sure.

I finally got in a few field days in early February, continuing with my rotation through the WMA. The results were much the same as in January -- large numbers of woodpeckers in an absolute sense, but still relatively low activity compared to the early spring of '08. A bumper crop of winterberries (the fruit of Ilex decidua) and poison ivy berries had drawn in hoards of American Robins and Yellow-rumped Warblers, and the Pine Siskin invasion had even reached this extremely pine-less corner of the South. But, of course, nothing campephilish, no encounters with the MIMDKWFTII. So far our early start on the season didn't have much to show for it, but I stuck with the strategy, hitting all the regions and keeping eyes and ears open.

Mid-February was also the time for the Great Backyard Bird Count as well as the Rusty Blackbird Blitz. Moss Island is good Rusty habitat, so I headed there for a day trip on February 14th. Sunrise caught me driving through Frog Jump, where a Rough-legged Hawk hung in the air over the highway. By then I was getting more accustomed to the strange biogeographic juxtapositions of the upper Delta region, and was able to just enjoy the bird without pondering the irony. I decided to spend about an hour in each of my defined regions, then head back home. I only came up with 35 Rusties, lower than what I often find, but the data come out the way the data come out. My woodpecker counts were improving a bit, with 16 Pileateds on the morning. On my way out, I came across Judy and her oldest daughter Beulah in their yard. Beulah is 17 and a very eager young outdoorswoman. Scott had equipped her with notebook, field guide, and camera just in case she came across anything.

Turns out she had come across something.

The previous morning, February 13th, she had hiked the ATV trail to Forked Lake. As she began to head back to the trailhead, a big black and white thing tore past her at breakneck speed. The account I wrote up at the time, based on my conversation with her, reads as follows:
She was walking back north on the Forked Lake ATV trail at about 11:15 (maybe she said 11:30) a.m. in the area that it crosses through the canebrake. She saw the bird flying past towards the north end of Forked Lake, moving very fast. She tried to get her camera up, but it was on power save and would not wake up fast enough. What she described was a bird that was bigger than a crow, black, and as she described it like the rear part of the wings had been painted white. The sketch in her notebook shows almost the entire rear half of the wings white, which would represent all the secondaries and most of the inner primaries. It also shows rather long wings. She didn't have time to note any other features, like crest, bill, dorsal stripes, etc. It's a story that has become very familiar over the last few years! The nature of the sighting, her description and her sketch are all spookily similar to the Harrison-Gallagher sighting of 2/27/04. She was confident that it had white all the way to the rear of the wings. She also commented many times on how fast the bird was moving. I didn't have my camera in hand when she showed me her sketch; I should have snapped a photo of it.

One thing I should add to that is that the bird was gliding the whole time of the sighting, without wingbeats. From what I gathered, it had been one fast swoop at pretty close range, with the bird banking as it passed her showing her its dorsal side. And in a flash it was gone.

Do I even need to repeat the mantra? All together now: What do we make of this report? Beulah literally grew up in these woods, and she has long been interested in their fauna. But, she's generally taken more of an interest in the bugs than the birds, and she's had little formal tutoring in the standard techniques of observational field biology. And once again we come across differences in language between the codified terminology birders are accustomed to and the more idiosyncratic ways that normal people describe things. This came up in the case of this sighting when Beulah independently told her tale to Melinda. Then she referred to a "white line on the back." The sketch she showed me distinctly indicated white bands along the rear portion of the wings. "Band" versus "line," "back" versus "rear." And, of course, like any normal person who has not been indoctrinated in rare bird documentation protocols, she looked at her field guide before drawing her sketch. I did observe that her sketch did not include much spurious detail, just a black bird with long wings and a big white band along the trailing edge, viewed from above. It boils down to what has become the standard unsatisfying Ivorybill sighting: bird seen very fast, no time to note anything but white secondaries, gone before the camera is ready to shoot. How much the brain can really take in accurately under those circumstances is always uncertain. It is also worth remembering that Scott photographed a White-winged Scoter on Rhodes Lake the previous March.

Still and all, it was something at least. Maybe things would pick up as we got into the second half of February. Dave Pereksta was going to be sacrificing his annual vacation on the Ivorybill altar yet again, and was due to arrive for two weeks at Moss Island (at his own expense) on February 23rd. I sure hoped we had some weather other than cold, rain, snow, and wind, and some exciting piciformic action to make his trip worthwhile.

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Thursday, September 24, 2009

Hot or Not?

Where's your hot zone?

A few days of sorting through my field notes and the seasonal summary reports produced the data I wanted. The numbers came out as:








Region
Effort (hrs)
Detections
D/hr
1
50
1
0.02
2
41
0
0.00
3
236
7
0.03
4
182
4
0.02
5
44
0
0.00
Total
553
12
0.02

The overall detection rate was about once per 50 hours. So, on to the question: Is the "hot zone" hot or not? Well, the Rhodes Lake area (region 3) does have the highest detection rate, looking at the raw numbers. And 92% of detections came from regions 3 and 4 (Hushpuckett-Forked lakes). But, 76% of our effort was put in there. I could do a Chi-square on this, but that would be misleading as it would treat each hour of effort as an independent sample, which of course it is not. So I'll just stick to the "O-test." And the significance of the hot zone appears to fail the O-test. At 0.02 D/hr we would have expected 2.6 detections in regions 1, 2, and 5; we had 1. That's not likely be a statistically significant difference however you analyze it.

What about seasonality? Were February and March really more active than the rest of the year? Here are the data grouped by months:








Month
Hours
Detections
Detections/hr
Feb
28
3
0.11
Mar
237
6
0.03
Apr
238
3
0.01
May
42
0
0
Jun
8
0
0
ALL
553
12
0.02

Remember that the February data are all from the last 2 days of the month, representing the flurry of detections that got the whole snipe hunt underway. So that apparent huge spike in February is not necessarily as impressive as it might seem at first glance. The dropoff in detections after March does look real, however. Combining Feb-Mar gives one detection per 29 hours; Apr-Jun averages one detection per 96 hrs. Again rigorous statistics would be hard to calculate, but the "O-test" would suggest this difference is probably real.

What about the absence of detections after April? Is that real? Well, you can't really tell. It's only 50 hours of effort, during which time you might expect 0.5 detections if there was no real drop in detection rates. When you are dealing with count data, an observed value of zero is of course not significantly different from an expected value of 0.5 no matter how you slice it.

Combining the seasonal pattern with the spatial one pretty much erases the "hot zone." Most of the effort in region 1, and nearly all of the effort in regions 2 and 5. happened after the seasonal drop in detection rates. If you allow for this, you can't conclude that there is any real pattern of higher detections in the areas around Rhodes, Hushpuckett, and Forked Lakes than in the rest of the WMA. You can't conclude there isn't either, of course; there just wasn't enough effort put in elsewhere early enough in the season to be able to say either way.

This made the initial strategy for 2009 clear to me. Spread out the effort across the WMA, and see if anything happens. Don't focus exclusively on the "hot zone," because it might not be any hotter than anywhere else. Time would hopefully tell.

**************

My next visit to Moss Island was January 21-23. I developed a rotation of regions, spending the morning in one, the afternoon in another, revolving through all 5 of them. This visit found clear and cold weather, with very nippy nights in the tent. As I said to Scott when he expressed concern about camping in such cold weather, I was just fine at 15F /-10C inside two mummy bags with both tops cinched shut, wearing a stocking hat and two layers of sweats. No problem! The cold weather combined with fluctuating water levels created some intriguing and beautiful effects in the sloughs:



I never managed to catch it on video, but the Winter Wrens liked to forage inside the ice caves formed underneath these hanging ice sheets.

Woodpeckerwise, it still remained relatively quiet. Drumming and vocalizations remained at mid-winter levels, with single-digit counts of Pileateds most mornings and afternoons. As I had noted last year, the woodpeckeriest areas remained regions 2 and 5, among the higher hardwoods with oaks and pecans. The southwest woods were especially a hotbed for Red-headeds, with a tally of 23 in just 3 hours on my final morning at the site.

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Monday, September 21, 2009

2009 Tally Ho!

Big white birds!

January 12, 2009

I had just crossed the county line from Obion to Dyer on Highway 51 when I caught the two big glowing shapes in a large borrow pit off to my right. A couple of swans, it seemed. Something about the scene just said "Trumpeters" to me even on first glance. I think the sight of a pair of swans on a small lake in a westernish-looking landscape triggered flashbacks from my years in Yellowstone, where Trumpeter couples were a frequent and memorable sight. I pulled off on the shoulder, reminded myself I was in Tennessee not Montana, and trained the scope on the birds. I was greeted with a pair of big honkin' jet black bills on a couple of snow-white, straight-necked swans, the smaller of which sported a yellow collar around its (presumably her) neck. Damn, they really ARE Trumpeters! I vaguely knew there were just a small number of recent records for Tennessee, and sort of remembered that there was a reintroduction program to our north. Whatever, wild or not, they were a regal pair.

I had spent a long morning birding around Kentucky Lake with Mike Todd, whom I had left at the overlook at Britton Ford in the Big Sandy unit of Tennessee NWR looking at five species of geese practically in one field of view. I fished out his cell phone number and gave him a call to get out the alert about the swans. I had to move on from the birds after snapping some crappy images, as I was due to meet Melinda at Rhodes Lake for the first evening watch of the 2009 season at Moss Island. Fortunately Mike was able get to the birds before dark and get some excellent photos of them. In the end the collar traced back to the reintroduced populations in Wisconsin. As the reintroduced birds are generally now considered established, wild, and countable by the various records committees of the Great Lakes states, it remains only to be seen what the Tennessee committee will eventually decide. If accepts them, it turns out they will be the first "wild" Trumpeters tallied in Tennessee in over 100 years.

So, having restored one extirpated species to Tennessee's official list, it was time to go try to add another!

I arrived at Moss Island about 3:00 p.m., after an absence of 7 months. It was, of course, a very different place in January 2009 than it had been in June 2008. Most fascinating to me was that the water was far lower than I had seen it before. Large amounts of dry land had appeared in the sloughs. Upon reaching the end of Rhodes Lake Road, I actually saw the sill for the first time ever. Previously it had only been a line of trees emerging from the water, or at most a vague lightness barely visible through a couple of feet of turbid blackwater. Now it was high and dry, a single-track graveled ATV road. I also took note of what appeared to be many downed trees and large broken branches all through the woods. In the gray winter leaflessness the broken wood shined like beacons signaling "Future Woodpecker Smorgasbord!" It had been a stormy summer and autumn, most notably when the remnants of Hurricane Ike passed up the Mississippi Valley in September. Even in our neck of the woods that storm had downed some trees; Moss Island had been about 200 km closer to the track. Many of the trees seemed to be broken and felled to the northwest, an appropriate direction to be Ike effects.

Melinda arrived at about 4:00 p.m., and we sat together out in the middle of the sill watching and chatting quietly while being entertained by beavers on the lake. That's the big drawback of being in the field in pairs; the temptation to chit-chat is great. The overall mood of the crew going in to this year was upbeat; we were getting an early start on the season, and if the MIMDKWTFII was still in the area we felt like we might have a fair chance of spotting it, WTFII. Kind of like opening day of the baseball season -- everyone has hope. Over the coming months most will have it slowly stripped away from them.

It was a quiet evening out at the lake. There was only a smattering of woodpecker drumming and vocalizing, just three Pileateds, a handful of Redbellies, and one each of Downy and Hairy. The highlight was the occasional flocks of Snow Geese passing over, a phenomenon that would keep up for the next couple of months. At dusk I returned to the barn to set up camp. This year I was planning on being at Moss Isand a good bit more, at least twice a month, thanks to more travel and expense money from Scott, and a less-used more reliable pickup I had bought in December. I had decided to leave my tent set up at the barn full time, along with some basic field gear, to make my frequent comings and goings easier. I could hook up to electricity, which made the long winter evenings pass more easily.

**********

Over the next couple of days Melinda and I spread our effort around the WMA. The goals for 2009 were to first determine if there even was any suspicious activity at all this year, and second to see if there was any notable spatial or temporal pattern to any activity there might be. Well, of course, primary would be to see and photograph an Ivorybill, but that was miles beyond the objectives that structured our daily routine!

It turns out that Moss Island isn't all that bad of a place to go birding in mid-winter. The south fields had grown up into excellent grassy oldfield habitat. Though this was obviously not the place to look for Ivorybills, I gave it an hour or so at midday and some scoping at dusk, yielding a LeConte's Sparrow, American Tree Sparrow, and Short-eared Owl. The days in the woods were good for generating high counts. I think this must be the continental motherload for Winter Wrens at this season, as I tallied 23 over three days. The woodpecker tallies were 17 Redheadeds, 55 Redbellies, 6 sapsuckers, 20 Downies, 7 Hairies, 29 flickers, and 23 Pileateds, still relatively low numbers compared to the abundances I found in March last year.

Neither Melinda nor I came across anything suspicious on the Ivorybill front. In the long solo evenings in the cold tent I had plenty of time to think about last year's results and this year's strategies. A big question for me was (assuming the double knock phenomenon was real, whatever it might actually be) whether our "hot zone" was a real pattern of activity or just a reflection of our distribution of effort. I decided I'd try to address this quantitatively, at least at a rough level. As a first step towards this I came up with five subdivisions of the Moss Island forests for tallying up detections and effort. For my own record keeping purposes I also added two non-forested regions. The divisions I came up with are based as much on points of access as anything else, and are marked on the map I posted earlier. The list is:

1. Northwest woods. Moss Island Road west of the barn, north through Cocklebur Flats to Mitchell Lake.

2. North central woods. From the barn eastwards, north of Rhodes Lake Road and west of Rhodes Lake. Mostly accessed by hiking or paddling the "canoe trail" east from the Barn. Also includes the western half of Willow Flat.

3. Rhodes Lake area and south. Areas surrounding Rhodes Lake, as well as the southeastern half of Willow Flat and the shrub swamp and forest south of the sill.

4. Southeast woods. Forked Lake, Hushpuckett lake, forested areas and ATV trails south of Rhodes Lake Road and east of Goosepen Road.

5. Southwest woods. All forests south of Moss Island and Rhodes Lake roads and west of the end of Goosepen Road.

6. Central Fields. Open and mixed areas along Moss Island and Rhodes Lake roads.

7. South Fields. Open areas along the southern parts of the WMA.

In 2008 all our detections had been in regions 3 and 4, except for my dubious double knock from area 1. Most of our effort had been concentrated in those two regions as well. On my return home I would try to tally up how many person-hours of effort we had put in in each region and each month. I thought the comparison to detections might be revealing.

The intrepid swamper in the Okefenokee in 1987


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Thursday, September 17, 2009

Potato Planting Plans

Getting carts, horses, and woodpeckers correctly aligned.

So two farmers are talking out in front of the co-op. The one farmer says, "Well, I didn't make out too good on the potatoes last year." The other one replies, "Is that so?" "Yep," the first continues, "I planted 5000 pounds, and I only harvested 2000 pounds." The second farmer says "No, I guess that's not so good. What are ya gonna do this year?" The first farmer answers, "Guess I need to plant more potatoes."

As we prepared for the 2009 "search season," I was determined to not just keep planting more potatoes. A couple of e-mails summarize my lobbying efforts towards this end, as well as my feelings about what our 2008 findings meant:

Subject: Re: IBWO and the like
Date: September 11, 2008
To: Scott Somershoe
Cc: Melinda Welton, "Jacob"

Howdy all,

Just some of my thoughts; sorry for the late reply, I was visiting a friend in San Diego and finally ticking off California Gnatcatcher and Black-vented Shearwater. No luck with LeConte's Thrasher, though, and never made it to the Salton Sea for Yellow-legged Gull.

As y'all have all heard me say before, I'm personally not all that thrilled with some of the search techniques that have been widely used in past years. Reconyx and ARU seem to me to be a waste of money and time; lots of effort with almost nothing to show for it. Not a single Reconyx shot of an Ivorybill anywhere ever in millions and millions of images. Likewise, critics have made it clear that devoid of context (like distance, direction, conditions, etc.) ARU is not capable of providing conclusive evidence of anything. I also think large-scale cavity surveys are a waste of time, tying up field crew person hours again without yet in all these years leading to any Ivorybill evidence at all. TARGETED cavity searches in a smaller area where roosting is suspected would be another matter. Mega searches with large volunteer crews have also not ever yielded anything, not even high-quality visual encounters.

I think (just my opinion) that job #1 is determining the overall pattern of activity, if any, this year. To my mind the best returns on detections per person-hour have been double knocks heard by observers either sitting or moving slowly, not engaged in any other activity (like cavity transects, servicing ARUs, collecting occupancy model data, etc.). Double knocks have a great detection distance (>>200m) and are detectable within a 360 degree range through forest cover. Initially, I think deploying potentially mobile observers both in areas of 2008 activity and other areas of interest on a regular basis would be the best starting point. These observers should be able to move immediately towards any even remotely possible DK they think they might have heard, and of course be equipped to document an encounter. If we can cover the area well earlier in the season, then we might just see a pattern of activity that would then narrow down the cavity search range dramatically and greatly increase the odds of a visual encounter.

Seasonality... overall, woodpecker activity in the upper Mississippi Alluvial Valley peaks January-March, then falls off dramatically; this pattern holds across species based on e-bird data and my own personal observations. There is a secondary peak happening right now, September-October. November-December is a lull. April-August is flat dead. I'd say this is our best guideline, and the DK pattern in 2008 was consistent with it. I'd think right after the winter holidays would be the time to gear up for the full 2009 effort.

As for anything short of The Photo being useless... not really. For one thing, if we can't see the bird we can't photograph it. A good sighting by a good observer would be extremely valuable. It would add a definitiveness to our goal; in-house it would allow us to recruit a lot more person-power, and let us know at least one spot where the bird definitely was (again, in an in-house context) rather than a spot where it just might possibly have been. So let's not fetishize The Photo to the exclusion of all other things. Seriously, tell me, if Scott got an unquestionable look at a perched bird, no doubt about it, but for some reason didn't manage to photograph it, wouldn't that still energize and motivate the troops nationwide? And get more resources redeployed to the area?

Just my thoughts,

Bill

*************************

Subject: Carts, horses, woodpeckers...
Date: September 23, 2008
To: "Jacob", Scott Somershoe, Bob Ford, Melinda Welton

Howdy all,

Some more continuing thoughts about priorities for the coming season at Moss Island...

When it comes down to the nitty gritty, what we have for sure there are double knocks. There are reports from the locals, glimpses from Scott and the other TWRA folks, but the only thing we have repeatedly, definitely, from experienced bird people, is double knocks. We've all been going on the working assumption that these DKs are from a big woodpecker, hence the efforts in cavity searches, cams on foraging sign, etc. BUT, and I believe this is a big but... I think we have jumped too far ahead. Since the only thing we have for sure is the DKs, it seems to me our primo number one job is actually seeing WHATEVER IT IS that is making these noises, rather than assuming we know what is making them and proceeding on that assumption. Because... what if we're wrong? What if it's not an IBWO making them? In that case, we could spend the rest of our lives enumerating cavities, putting cams on foraging sign, etc. and never find anything. So I think that before we invest a whole lot more resources in anything else, we HAVE to get a visual on the source of the DKs. Anything else is putting the cart before the horse.

And what if we find out that it's not an IBWO? Well, we'll be extremely disappointed. But we'll also have made a hugely important discovery.

I should add, it doesn't have to be *we* who get the visual on the double knocker. If anyone anywhere gets a visual that confirms or refutes that these sounds are coming from IBWOs then the effect is the same. But UNTIL that happens at Moss Island, the Congaree, or out back behind Joe Bob's fish camp in East Jesus Mississippi, then I think that should remain our top priority. Which again means people sitting quietly or moving slowly, equipped to pursue and hopefully document, not distracted by other duties, and no noisy survey crews stomping transects. In spite of our personal beliefs, the strong similarities to tropical Campephilus DKs, the spatial and temporal patterns that indicate a mobile, biological source, etc... We don't really KNOW to a scientific certainty that what we have been hearing is even from a bird, much less a large woodpecker.

Bill

To my surprise, the overall gist of these suggestions was accepted readily with little resistance for the 2009 Tennessee work (what happened elsewhere I really don't know). I can flatter myself by imagining that this was because of the amazingly persuasive power of my arguments; but more likely it was because the severe limits on available personnel and time didn't permit anything more ambitious that this.

And now it was just a matter of waiting for the season to begin.

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Monday, September 14, 2009

Why the Rush?

For some reason, a large number of people seem to be in quite a hurry to declare the Ivory-billed Woodpecker extinct. This is not a new phenomenon; it has been going on for nearly 100 years. Nor is it unique to the Ivorybill; there always are voices declaring the extinction of organisms that have not gone missing for nearly enough time to justify such a judgement. In the case of North America's three avian phantoms (Ivorybill, Bachman's Warbler, and Eskimo Curlew), it is worth keeping in mind that neither the AOU nor the US FWS has formally declared any of them to be extinct. The death proclamations are instead generally sounded by prominent individuals in the Academic and birding communities rather than the major institutions.

This leads me to wonder why. What advantages are there to decreeing a species to be extinct? I can think of several arguments that would likely be advanced if I actually posed this question face-to-face to some of the people involved. Many of these points could be grouped under "common sense." These are variations on the theme of "with it having been so long since an indisputable piece of evidence, it is just common sense that the bird is not still out there." In this view, accepting extinction is an overcoming of denial and irrational hope. However as with so many applications of "common sense" to questions that involve very large or very small numbers, statistical analyses don't support this "common sense" view, even if you reject all of the sightings, photographs, and videos since the Singer Tract birds.

I've done my own various back-of-the-envelope estimations that suggest that statistically speaking the upper limit for the global population estimate for Ivorybills remains well above zero. Actual rigorous and peer-reviewed studies have found the same thing, and have also found that it is in fact not at all impossible for a very small breeding population to persist for many decades. In a semi-humorous exercise, if I just take my own personal lifetime experience which includes zero firm Ivorybill detections, estimate the amount of time I have spent in coastal plain bottomland forests, take a reasonable value for detectability of the bird, and get an estimate of the total amount of this forest in North America, then do all the multiplication, I come up with an upper limit for the global population of something like 1000 birds. This brings up the next question: Are there 999 other people like me? This is what it would take to bring that upper bound down to 1 bird. Sure, there are 1000 other birders who might report an Ivorybill if they saw one (and many more who would not), and 1000 other people who have spent as much time in bottomland hardwoods as I have. But how many other people are there who fit both criteria? Not 1000. Birders mostly shun the swamps. Forget "common sense." The survival of the species can't be ruled out from a statistical, scientific, data-based point of view, not just at the theoretical absolutist level of the impossibility of proving the negative. It is those who declare that the species is clearly extinct who are speaking from a position of personal belief, nonrational impulse, and (dare I say) faith, not justifiable by science, data, or statistics. Most birders, even experts who should know better, vastly overestimate the efficiency of the transcontinental birding community as a bird-finding machine. The vast majority of individual North American birds live out their entire lives without ever being seen, identified, twitched, or reported by any birder. For dozens of individuals of a woodland species to go undetected decade after decade even in the eastern U.S. is in fact exceedingly easy, not virtually impossible.

Given this, why do intelligent, reasonable people still want to rush ahead and erase the Ivorybill from the roster of the world's birds? Many doubtless want to end the embarrassment of having people looking for extinct birds, fearing it makes us look like bigfoot hunters. I think this is probably what underlies the fiercely negative emotional reaction many people have to suggestions that there might still be an Ivorybill flying somewhere. But, this is based on the flawed "common sense" pro-extinction conclusion. The same applies to people who do not want public resources wasted on looking for an extinct bird. There are legitimate issues in how much, where, and how, but once again it is incorrect to base your arguments on an assumption of extinction. The whole crusade against "wasting money on an extinct bird when we have real species that need saving" is founded upon the fundamentally incorrect presumption that the Ivorybll can be reasonably known to be extinct, ergo all spending on it is wasted. Once again, even if you reject all post-Tanner evidence you still cannot safely conclude the species is gone.

With the "extinction question" being very much an open one statistically speaking, what do you gain by ditching the Ivorybill and those other phantoms? Well, you can leave three species out of your field guide, a rather miniscule savings. You don't have to spend federal money on them; although most of the time in recent decades there has not been any federal money being spent on them and it only started up recently (for a few years for one species) because of some triggering incidents. You get to leave them out of the EIS process, a "plus" of dubious value. Or perhaps you just get to feel smug and superior to all those nitwits who still cling to fairy tales (even if it is in fact your position that is scientifically unjustifiable, not theirs).

So what would have been gained if the near-universal consensus had stayed at "very rare, possibly extinct" without the loud sub-chorus of "It's extinct, stupid; any fool can see that?" Well, for one thing, birders and ornithologists would not be embarrassed about putting effort into trying to find relict populations or individuals, and would feel less need to keep their activities secret for fear of ridicule and professional retribution. These birds might have stayed on the birding radar enough that we might actually be in a better position to know now if there are indeed any left, and where. Ridicule is never a helpful activity in science; amazingly it has become almost the norm in some circles of late, usually espoused by people who believe they are defending science when they are actually hurling their jabs and taunts from a scientifically unsupportable peanut gallery.

We on the Tennessee search crew do not claim to have heard or seen an Ivory-billed Woodpecker, ever, anywhere. At Moss Island we do claim to have heard sounds that are exceedingly close to what an Ivorybill double knock might be expected to sound like, repeatedly, under circumstances that do not promote simple, ordinary explanations. Given the statistical reality that this species is quite possibly not globally extinct, and the location of the site within the generally accepted likely historical range of the species, it would be irresponsible not to follow up on this. For a wildlife biologist in the public trust with jurisdiction over non-game birds, failure to do so might even amount to professional negligence.

What can possibly be wrong in continuing to hold to a scientifically and statistically justified rational hope? And what can possibly be good about ditching this hope based on emotional, poorly thought out, unscientific "common sense?"

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Thursday, September 10, 2009

Into Summer

Things that bite, things that sting

I made two more trips to Moss Island in 2008, one in late May and one in early June. I had intended to keep coming every month or so for the rest of the year but for various reasons that just never happened. The rest of the crew was occupied with other nesting season projects, so I was it for the time being. As I had planned, I put some focused effort into covering the southwestern portions of the WMA where the higher ground supports a more diverse bottomland hardwood forest. I also was now video camera equipped, so you'll start to see video clips popping up in these blog entries. On my arrival back on site on May 28th, I undertook a rather grueling slog around the perimeter of this southwest woods area to scope out access and viewing spots. It had not looked so bad on paper, but by the time I was done with it I had covered about 10 km, significant portions of this through boot-sucking mud. Turns out that it really isn't such a treat to beat your feet on the Mississippi mud (culturally challenged may click here , here, and here to see what the hell I am referring to; be warned that the last link is an annoying music classic from the Muppets).

There are four points of relatively easy access to this large blob of mixed hardwood forest. You can hike due south from the barn, make a short field crossing, and enter it at its widest spot. You can park at the end of Goosepen Road and enter it at the narrow isthmus where it connects to the more eastern forests. You can approach it from the south and hike along the southern fringe, Or, you can park on the shoulder of Great River Road overlooking the forest's western edge and listen. I did all of these at various times. Not wanting to entirely forsake the earlier "hot zone" I also spent some time around Rhodes and Hushpuckett Lakes.

The habitat in the southwestern woods is a better approximation to the standard model of "core" Ivorybill habitat than is the rest of the WMA. There are a fair number of reasonably good sized hardwoods, and they are of the sorts of species that one reads about in the old accounts: oaks (mostly water and nuttall/shumard), sweetgums, hackberries, elms, pecans. The understory is fairly dense, however, which interferes with sight lines and sound propagation at this time of year. There are also frequent thick carpets of knee- to waist-high poison ivy and (much worse) stinging nettles. There are no trails in these woods; it's all bushwhacking. The mosquitoes range from passable to almost intolerable. Over the decades I've become exceedingly familiar with this sort of habitat and its summertime arthropod populations; it's just something you take measures to deal with:



Pants inside shoes inside boots to keep ticks and chiggers on the outside of the clothes, all clothes and no skin sprayed with DEET (including hat, important for protecting face), fanny pack with attached seat cushion (also sprayed with DEET) to reduce chiggers picked up while sitting on logs, buckskin vest gives extra mosquito protection to back and shoulders, hair and beard protect most of face and neck. Though not the most comfortable of work environments, it is certainly doable with the right preparations. Developing a lifelong tolerance for mosquitoes and chiggers is helpful, too; I tend to find that people who have not been exposed to these creatures very much before seem to react physiologically (and of course psychologically, too) more strongly than do we who have had dozens of chigger bites and thousands of mosquito bites on every square centimeter of our bodies accumulated over the years.

The woodpecker abundances in these areas were quite high in a relative sense, but all across the WMA the woodpeckers continued to be much quieter and less conspicuous than they had been earlier in the year. As for anything even vaguely campephilish, not the faintest hint, either in these new areas or back in the February-April "hot zone." It also seemed like no one at all uses this WMA. When I hiked a path in June, the only bootprints I'd see in the mud on it were the ones I myself had left in May. It did get to be a bit of a downer, spending the days sweating, smelling bug spray, being stung by nettles and bitten by skeeters, finding nothing, and nothing, and still nothing.

Of course there was actually tons of stuff being found, just not the mythical phantom target of the quest. This is a problem birders often have, even when chasing real birds (oops, did I say that out loud? You know what I mean...). You have a quite fine day in the field, full of fascinating sights and sounds, but since you didn't find the one thing you were specifically after it winds up feeling like a failure. This was the reason I largely abandoned stakeout chasing in the 1980s. But the present quest wasn't a run-of-the-mill stakeout, this was the great schismatic ornithological conundrum of my generation.

I'll finish off the 2008 field season with a short compilation of snippets of some of the many other things my video camera and I encountered on these final couple of visits. I originally edited it more for the interests of non-birding friends, but it will give some visuals to complement all this text. Plus, for those of you who have only seen this habitat in the winter, it'll give you a sense of the other half of the year. It is roughly in three sections -- first scenery, then critters, then our intrepid swomp stomper slogging, sitting, and generally searching (must always remember, the filmmaker is the true star of a nature film, right?). There's more video to come from the 2009 season.



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Monday, September 07, 2009

Firebirds

I remained at Moss Island for two more days, with no more hints of the MIMDKWTFII. Bob Ford and one of the TWRA field techs were in the area as well, with similar (non) results. I did make my first explorations into the trail-less wildlands I have dubbed the "southwest woods." Here I found out where all the oaks were hiding, along with sweetgums, pecans, and other diverse bottomland hardwoods. Given this, and whatever had happened along the main road on the 22nd and 23rd, I felt like I should start spreading my effort around more widely across the WMA, rather than focusing so heavily just around Rhodes Lake. It's always hard to know in the case of any bird (assuming the MIMDKWTFII is some sort of bird) that is found repeatedly but not continuously one defined area whether that is because the bird prefers that spot or because the observers are just focusing on that spot and ignoring other areas (Patagonia rest stop effect again).

I made another trip to the site in early May. My results and thinking at this time are summed up in this e-mail I sent to the rest of the crew:
Subject: Moss Island this week
Date: May 9, 2008
To: Scott Somershoe, Melinda Welton, Bob Ford
Cc: "Jacob"

Just returned, saw just about everything but the object of the search. Major movement of migrants. The most impressive event was Wednesday afternoon when I took a long walk through the woods from the barn northeastwards, then around to the far side of Rhodes Lake. The Obion was rising again, and spreading into the forest in that area. All along the edge of the advancing water the warblers, thrushes, and other passerines were actively feeding on the critters fleeing the rising water, concentrating them in the lower 20' or so of the forest and in areas of very open understory. It was the most impressive display of EASILY SEEN migrants I think I have ever encountered away from coastal fallout zones! I had 20 species of warblers on that walk, which didn't even begin until noon, and the majority of the individuals were seen, not heard (singing was pretty quiet). I also had more Gray-cheeked Thrushes in one day than I can every recall having seen south of their boreal nesting grounds, along with plenty of Swainson's and Veeries.

Water levels peaked yesterday evening and were dropping slowly again today. The road was open all the way to the Rhodes Lake turnaround (one small shallow ford just before the lake, with pickerels literally laying in the road on their bellies, dorsal fins sticking up above the water shark-like, grabbing smaller fish that were swept into the road by the current!), but the sill was still underwater and I had to wade in waist deep water on the ATV road to get from the Obion side back to the road side after my warbler-filled hike on Wednesday. Lacking waders, I just held my gear overhead and got wet (it was a warm day). The ATV trail south from the mid-road turnaround on Rhodes Lake road is completely open; the one northeast from the barn is still flooded just a few 100m into the woods.

I covered the areas north of the road from west to east, and the areas south of the road from east of Goosepen road to west of Hushpucket and Forked lakes. East of the lakes, the sloughs were still too deep for hiking. Nothing IBWO-ish to report. Leafout is near 100%, except for the pecans which are less than 50%. Pileated activity is increasing some, but you'd still be hard-pressed to turn up a Hairy for money. Good sunset chorus of drumming (mostly Pileateds) at Rhodes lake, and the sunset sit is much easier now with the road passable. Mississippi Kites and nighthawks now provide aerial entertainment while you sit.

One or two Swainson's Warblers in the turnaround-ATV trail area. Not heard a single Cerulean yet.

I took a few more looks at that large area of hardwoods in the southwest part of the WMA, from Goosepen Road to Great River Road. It is the largest chunk of real mixed hardwood forest on the site, with most of the oaks. It has also been covered the least, probably. Scott had made comments that the habitat there was not very good, but none of the habitat at Moss Island is very good by Congaree/Big Woods standards. To me it looked as good as anywhere else, and actually has quite a number of large (by local standards) oaks, elms, sugarberries, and pecans. I will probably focus there on my next visit, since it has gotten relatively little coverage, and we're not finding much anywhere else.

More thoughts about habitat quality... the areas around Rhodes Lake that were our "hot zone" February-March are mostly Black Willow, Silver Maple, and Cottonwood. I doubt you'll find any reference suggesting that as even close to "good Ivorybill habitat." So if we've got a bird there, we can already throw the habitat books out the window. One thing I have been pondering is this:

Those willows are huge and ancient, for a generally small, short-lived tree. The cottonwoods are also huge and showing their age. I am thinking maybe there is a senescence pulse going on with an age class of willows and cottonwoods, and that has been providing foraging habitat. One thing I have noticed in the last couple of visits: there is no Cypress/Tupelo phase at Moss Island. There are a very few scattered cypress trees, and I have not yet seen a single tupelo. All the trees I thought were tupelos in the winter, like those ones in the sloughs with their nice prominent buttswells and tupelo-like bark, have proven to be green ash now that they are leafed out. My guess is that the cypress/tupelo was completely logged out early in the 20th century, and that scraggly willow-cottonwood-silver maple community grew in to replace it. Now those old, almost even-aged stands of fast-growing pioneer trees are getting to their expiration dates, and becoming a woodpecker smorgasbord. But I doubt they would provide suitable Ivorybill nest sites, even if they provide winter foraging grounds. Hence my continuing interest in the mixed hardwood forests farther west, in spite of the relative lack of detections there.

Just some ramblings

Bill

In the middle of May came our annual opportunity to hear S. J. Tucker a.k.a. Skinny White Chick perform. She's a Memphis based singer/songwriter, a tiny woman with an enormous voice. She opened with a set of entirely new music from her latest CD. When she picked up her djembe and started into Firebird's Child, I was mesmerized:
<a href="http://music.skinnywhitechick.com/track/firebirds-child">Firebird's Child by SJ Tucker</a>
Of course the song has nothing to do with woodpeckers, it's about having the courage to live in your passions. But does make me wonder if perhaps we should use a big-ass djembe as a double knock simulator!

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Friday, September 04, 2009

Zebras Playing Clarinets

"We were just coming in the road where you come in to the woods, and it flew right in front of us!"

Gordon and Judy were telling the tale in tandem as I stood in their dining room. They had been the second post-flood vehicle to make it in the road, arriving about 6:00 p.m., which was just about an hour ago as we stood there. They were anxious to get home before anyone else did, fearing thieves and vandals taking advantage of the vacated house and premises. And rightly so, based on my own experience that same evening just a short ways down the road.

"It stopped on that twisted round tree about 60 feet in from the road." He stopped the car and told the rest of the family to get out and keep an eye on the tree where it had landed and immediately shuffled around to the back side of the trunk. The camera was still packed in the back of the car; Judy tried to find it but wasn't able to get to it fast enough. They all saw it fly off a couple of minutes later. Both Bob Ford and I heard the same story about this part -- "When it flew it banked and you could see all that white, all the way down the back, and a red head." He and Judy both stressed how big it was, "bigger than a woodpecker." They don't consider this bird to be a woodpecker, leaving that category for things of Pileated size and smaller. The bird flew out of sight, according to Gordon and Judy at breakneck speed. Gordon said it "didn't fly like a woodpecker, it just goes hard and straight without that up and down." Judy was amazed at how it just went right off through the woods at top speed, steering around every twig and branch without skipping a beat, contrasting it again with "woodpecker" flight. She laughed that she knew why it was going extinct, that flying like that they must kill themselves ramming into trees at full throttle all the time.

Just after it got out of sight, Gordon said they heard "that sound it makes." He's described this call before, coupled with a sighting at Rhodes Lake about a year or two earlier. He said the call was one note, on a level pitch, not "broken up like a woodpecker," and "kinda eerie." He and Judy said they had read it was supposed to sound like a tin horn, but that wasn't right. They agreed it was lower than that. I asked Gordon if he could name a musical instrument that might be a better match. He thought about it a good bit, then answered:

"I'd say maybe a clarinet would be the closest."

Through all this informal debriefing I'd been careful not to give them leading information, as had Bob also been when he talked to them separately the next morning. But after Gordon told me this I asked him if he had ever read the old tales that said you could imitate an Ivorybill's call with a clarinet mouthpiece. He and Judy both looked surprised and said they'd never heard that before.

After telling their tale, I told them mine of the drunken would-be boat thieves. Gordon is a former deputy sheriff who had worked undercover vice and still sports a chest-grazing goatee; he was not at all surprised. We figured they were probably checking to see if the house was still vacant, and finding that it wasn't they headed on down the road to see if there were any other easy pickings. He called in to the county sheriff and the refuge manager, giving them the plate and description. Word came back to me the next day that the manager, Carl Wirwa, was furious and wanted to know right away if they ever showed up on the site again so he could bust their sorry behinds.

And now time for the eternally recurring question: What to make of their sighting?

I keep in mind that we birder sorts have learned a very particular way of seeing birds, along with our own language for describing them, and that normal people don't share these. We have probably all had the experience of someone giving us a description that might sound like a dead ringer for (as an example) a redpoll, only to have it turn out to be a chipping sparrow when we finally see the bird. Plus there's the phenomenon of having one promising sighting, and then following that up with a bunch of overeager mis-IDs. And there is especially the parallel phenomenon of rarity bias: When you present someone with the choice of two possible explanations, most people are emotionally drawn to the more exotic, exciting, special, rare, and unlikely option. Many people, including all competent birders, learn to resist this and, as they teach in medical school, think "horses" when they hear hoofbeats, not "zebras." But in the minds of the general public, zebras tend to greatly outnumber horses. Just about every old-time hunter, fisherman, or swamper in the south seems to have tales of Ivorybill encounters to tell when you get to know him or her well enough. Hence I fully understood that the vocalization they heard might have been a coincidental wood duck or something else, not the the bird they saw at all, and the flight they describe might just be normal Pileated flight seen through the eyes of someone who hasn't actually looked that closely at Pileateds before. Hell, the bird they saw might not have been any kind of woodpecker at all. But those two things -- the flight and the call -- did get my attention. Though I was definitely skeptical, I was certainly intrigued enough to change my plans for the next morning. After all, once in a blue moon it really does turn out to be a zebra; otherwise we birders would not spend so much of our lives sorting through thousands of peeps, gulls, and sparrows.

April 23, 2008

I wasn't going to retool my whole approach based on a non-birder sighting, no matter how excited they may have been. But it was easy enough to take an early morning walk west from the barn on the main road towards the levee and Great River Road. I set out at 6:00, right about sunrise, creeping along and listening closely. It was both a noisy morning and a quiet morning. Noisy in that this stretch of road proved to be an excellent migrant trap and the still-flooded woods were full of all the same sorts of sounds I had experienced yesterday evening around Rhodes Lake; quiet because there were still none of the anthropogenic background bangs, clunks, and such from off-site. It was another of those clear, calm mornings.

At 7:01 what sounded to me like a good, solid double knock of the MIMDKWTFII type rang out from due west of me. I guessed the distance at about 300m; this put it in the flooded woods, maybe 100m north of the road, and quite close to the spot of yesterday evening's report. My skepticism was significantly dented by this. I picked up my pace, trying to strike the balance between speed and the ability to hear. I also continued to survey the background sounds -- no "river noises," no highway traffic, and there's no highway bridge in that direction. And no more double-knocky sounds either. I sent a text message to Scott (enough cell coverage for SMS, not enough for voice) while I continued to hear nothing. His response was a surprisingly curt "did you record it?" I texted back that I had no sound recording equipment, to which he responded "we need something documented." Still stinging from the Cornell-ARU incident, it seemed. Of course even if I had been in possession of a sound recorder, it likely would not have picked the sound up. I was walking slowly, not sitting still, so even if the device had been running it probably would have mostly recorded the sounds of gravel crunching and clothes scraping. We weren't going to get a sound recording unless we had another series of double knocks, not just isolated individual DKs. This would allow time to get the device operating, stationary, and pointed in the right direction. So far there had only been one series heard (by me on 3/11/2008); who knew how long it would be until the next time?

As the minutes wore on with still no more suspicious sounds, the creeping uncertainties grew. Unlike the 3/21/08 incident at Rhodes Lake, all I really had was a compass direction. There was no second bearing from an observer at a different location to triangulate distance. I guessed 300m, but that was of course based on an assumption that the sound was inherently similar in volume to my previous encounters -- "I prove A by assuming A." Could it have been much louder and off-site? Unlike the 3/11/08 series, I had not had the opportunity to hear and closely study the sound multiple times, listening for all the audio clues as to its true distance and nature. All I could say was that it didn't "sound" that far away, but I could not give more specific reasons. I was now learning first-hand about the difficulties of knowing what to make of single-observer, one-time, apparent "double knocks." Still, though my perceptions were all I had, I could report and record them just the same. What weight if any to give to this on down the road could and would be decided later.

My doubts were ramped up about a half hour later when the county road grader came rumbling down the road from the direction of Great River Road. Could that have been the source of the sound I heard, perhaps while it was in transit down the highway from another spot, or being offloaded from a trailer up on the levee? I suppose; just the same as any other off-site mechanical noise, that is not what it had "sounded like" to my ears. More than that I really could not say. As the grader continued past me, out of sight, then returned shortly headed back out to the west and off the WMA, I followed it with my ears. No double-knocky sounds. About 8:00 a series of "river noises" began. At least I could eliminate them; they were as usual loud and distinctive, and clearly had not been in progress at 7:01.

I finished my hike to the levee and back to the barn at 8:30 a.m. I loaded up in my kayak and headed northwest into that same patch of woods between the road and the lakes, this time afloat. There are many areas with fairly large trees in here, which proved to mostly be sugarberries and cottonwoods with only a few oaks or other hardwoods. There were also large areas of willow and scrawny silver maple around the lakes and sloughs. The most impressive stands of trees were actually the ones fairly close to the road, as well as along the western fringes west of Cocklebur Slough and south of Mitchell Lake. I heard no more double knocks and saw nothing out of the ordinary, as has become par for the course. Same-day follow up on suspicious activity yields... nothing. As I had noted the other time I visited this area on March 20th, there is a high level of woodpecker activity, as high as anywhere else I had seen at Moss Island. With the flickers and sapsuckers having vacated for the season we were now down to five species, however. There were also plenty of passerine transients around; for the day I found 20 species of warblers.

Still no zebra.

A club I should join?

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