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Not So ‘Virgin’ Forest: The Singer Tract Myth Debunked

Update: This post includes hard data about the extent of old growth in the Singer Tract (scroll down past all photographs) and in ivorybill home ranges. The general points made below remain valid, although some of the wording is perhaps too strong; Tanner overestimated the amount of old growth in the Tract ( at “over 80%” v. 72% in fact), and the Mack’s Bayou home range was predominantly second growth.

This post is a companion to the previous one and to others discussing habitat conditions in the Singer Tract. Those posts reference Richard Pough’s 1944 report to the Audubon Society. Pough, whose study was never published, noted that much of the Singer Tract had actually been under cultivation prior to the Civil War. But it’s worth taking a closer look at just how much.

Tanner characterized the Singer Tract as “the largest tract of virgin timber in the Mississippi Delta,” contending that it contained “120 square miles of virgin forest in 1934”. He also wrote that the largest plantation “had about 3000 acres under cultivation,” while suggesting that “some of the early settlers along the Tensas River cleared land along the river banks for cotton fields.” Thus, the myth of the Singer Tract as virgin forest was born.

It’s not clear where Tanner got his information, but some of his characterizations are not supported by the historical record; the language about “early settlers” almost seems disingenuous when one looks at the history of Madison Parish. (Rootsweb has many pages devoted to this subject, and I’ve drawn heavily on them for this analysis.) As should become evident, there was a great deal of human activity in and around the Singer Tract, especially prior to the Civil War. I will suggest that most, perhaps virtually all, of the arable land in the parish, had been cleared for agricultural purposes and that the Singer Tract was a mix of second growth and remnant old growth, most of which was in the lower-lying, wetter areas that Tanner deemed to be less suitable for ivorybills.

A 1937 Masters thesis in economics by Robert L. Moncrief, “The Economic Development of the Tallulah Territory”, provides a great deal of information about the parish and its history. In the post-Columbian era, the area was very sparsely settled until the 1830s. Madison Parish was established in 1839, and in 1840, steamboats began plying the Tensas River. A major population influx began in 1836, and the population kept growing until the Civil War, going from 5,142 in 1840 to 14,133 in 1860. The war led to a dramatic decline to a mere 8,600 in 1870. Over the next couple of decades, the numbers grew again to 14,135 in 1890. Changing economic conditions and the boll weevil outbreak caused another decline that was only reversed between 1920 and 1940, when the number of residents reached 14,826. By 2010, it had fallen to 12,093.

Cotton and the quality of the soil drove this influx. By 1850, there were 27 landowners in the parish who owned more than $20,000 (over $590,000 in 2015 dollars) worth of real estate. The largest holding was valued at $140,000 (well over $4,000,000 in today’s dollars).

According to Moncrief, “the newcomers cleared away the heavy forests and planted the new ground in the favored crop then, as now –– cotton. They cleared all the lands fronting water courses (which are the highest and most desirable lands for cultivation in this region) to form a continuous line of plantations along the streams.” Streams in this context refers not just to the Tensas but also to the smaller non-navigable bayous. Cotton raised along the smaller streams was brought down to the Tensas in flat-bottomed boats.

Moncrief’s thesis also includes figures for cotton and corn production in Madison Parish. Cotton production peaked at over 46,000 bales in 1858. (Pough was apparently incorrect in stating it was over 100,000 bales; he may have combined the total with that of an adjoining parish.) It had fallen to 1,830 by the end of the war. Production recovered between 1870 and 1875 and reached a postwar/pre-boll weevil peak of 25,981 bales in 1890, about the same level of production as in 1936. Corn production peaked at 618,620 bushels in 1859, falling dramatically after the war, peaking at 836,000 bushels in 1909, and then falling to 320,000 by 1936. My crude, back of the envelope estimate based on  yields of 5 bales per acre for cotton and 15 bushels per acre for corn, suggests that between a quarter and a third of the total acreage in the Parish was under commercial cultivation prior to the war.

While Moncrief’s paper evokes Tanner by describing the Singer Tract as 81,102 acres (126 square miles) of virgin timber, it also notes, “The tract includes several abandoned and grown up plantations, which after the Civil War, reverted to the state and were later sold to the present owners.” The ruins of one plantation house are still standing, deep within the Tensas National Wildlife Refuge.

While it was adjacent to and not strictly part of the Singer Tract, the story of the Frisby Plantation is illustrative. The plantation was established in the early 1850s with land acquisitions taking place over the next decade. Norman Frisby, the founder, was murdered by his nephew by marriage in an 1863 in a dispute over property. When Frisby’s widow was forced to sell the plantation in 1870, it totaled 19,479 acres, and its crops generated over $77,000 in revenue (the equivalent of $1.36 million in 2015). Tanner visited the site of the plantation and photographed one of its old fields. I haven’t been able to pinpoint the location of the old house; one 19th century survey survey seems to place it in Tensas Parish, near Fool’s River. Another account (from the history of the Sharkey Plantation discussed below) says it borders Disharoon (or Dishroom) Bend, much closer to the core of the Singer Tract. As shown on this overlay of 1875 land ownership on a modern map, the Frisby holdings included parcels adjacent to Mack’s Bayou and on Dishroom Bend.

The maps help flesh out the story. An earlier and incomplete parish-wide map of patentees shows that many parcels in the Singer Tract were purchased well before Frisby started acquiring land in the 1850s. Lands purchased in the 1840s include parcels along John’s and Mack’s Bayous, which makes sense since frontlands along streams were most desirable. This history of the Sharkey Plantation reveals that land sales began in the heart of Tanner’s search area during the 1840s. The author explains that the Sharkey plantation and others like it were more like communities, with a cluster of families (and presumably their slaves) living in close proximity, near a watercourse.  The 1875 map shows that much of the Singer Tract remained in private hands even after many parcels were abandoned during the Civil War.

Perhaps even more telling is this hand drawn map of Madison and Carroll Parishes from 1862. It shows the locations of towns, roads, ferry crossings, and plantations in the Singer Tract area. While it is incomplete and John’s Bayou is not shown, Sharkey Road is there, cutting in a southwesterly direction from the Richmond-Carthage road, crossing Alligator Bayou, and the Swearingen parcel. Another road crosses the heart of the Mack’s Bayou home range and the Tensas itself. The map delineates abandoned plantations and appears to show that, except for those abandoned areas, some cotton was being grown in every division of the Singer Tract. However limited the agricultural activity may have been in these sectors, the area was hardly a primeval wilderness; habitat had been fragmented; and old growth conditions were likely restricted for the most part to areas unsuitable for farming.

This passage from an 1885 article from the New Orleans Times-Picayune sheds some additional light on conditions in the area both before and after the Civil War. “But little has been said about Tensas River and Joe’s Bayou as, but little interest is there as compared with former years. Before the war there was a continuous planting interest all along those two streams but overflows and the war left them to grow up into weeds and bushes. In 1870 Mason, and later Loyd bought cattle from other parts of the country and carried them to those bayou places for pasturage, wherein a few years they made large sums of money. This was in the neighborhood of Quebec, which before the war was a flourishing little city, shipping 7090 bales of cotton. It was at the junction of the Tensas River and the railroad. It is now a waste place and to pass there on the railroad you would never know that a town had been there.” (In The Race to Save the Lord God Bird, p.76 Hoose plays into the virgin forest myth by claiming that railroads “finally reached the Tensas River sometime around 1900.”) Quebec was just a few miles outside the tract, near Bayou Despair, where Tanner listed a pair from 1934-1936.

The Rootsweb pages provide a couple of additional and important pieces of information.

Theodore Roosevelt visited Madison Parish in 1907.  Roosevelt’s descriptions provide added detail about conditions in and around the Singer Tract several decades after the Civil War. According to Roosevelt:

“Beyond the end of cultivation towers the great forest. Wherever the water stands in pools, and by the edges of the lakes and bayous, the giant cypress loom aloft, rivalled in size by some of the red gums and white oaks. In stature, in towering majesty, they are unsurpassed by any trees of our eastern forests; lordlier kings of the green-leaved world are not to be found until we reach the sequoias and redwoods of the Sierras. Among them grow many other trees–hackberry, thorn, honeylocust, tupelo, pecan, and ash. In the cypress sloughs the singular knees of the trees stand two or three feet above the black ooze. Palmettos grow thickly in places. The canebrakes stretch along the slight rises of ground, often extending for miles, forming one of the most striking and interesting features of the country. They choke out other growths, the feathery, graceful canes standing in ranks, tall, slender, serried, each but a few inches from his brother, and springing to a height of fifteen or twenty feet. They look like bamboos; they are well-nigh impenetrable to a man on horseback; even on foot they make difficult walking unless free use is made of the heavy bush-knife. It is impossible to see through them for more than fifteen or twenty paces, and often for not half that distance. Bears make their lairs in them, and they are the refuge for hunted things. Outside of them, in the swamp, bushes of many kinds grow thick among the tall trees, and vines and creepers climb the trunks and hang in trailing festoons from the branches. Here, likewise, the bush-knife is in constant play, as the skilled horsemen thread their way, often at a gallop, in and out among the great tree trunks, and through the dense, tangled, thorny undergrowth.”

The most salient point here is that Roosevelt’s “great forest” applied to low-lying areas in which there was standing water (something that Hoose glosses over). Roosevelt also saw three Ivory-billed Woodpeckers:

“The most notable birds and those which most interested me were the great ivory-billed woodpeckers. Of these I saw three, all of them in groves of giant cypress; their brilliant white bills contrasted finely with the black of their general plumage. They were noisy but wary, and they seemed to me to set off the wildness of the swamp as much as any of the beasts of the chase.”

 

A photograph from the hunt is here. Tanner seems to have been unaware of the Roosevelt encounter. Roosevelt’s visit came just 17 years into cotton farming’s second decline and 52 years after the end of the Civil War. Habitat conditions are likely to have been poorer in general than when Tanner was there 3 decades later. The relative ease with which Roosevelt saw three ivorybills (despite their wariness) suggests they were not uncommon in 1907 and calls Tanner’s assumptions (pp. 48-50) about fire, tree death, and population influxes between 1911 and 1930 into question.

There’s another gem in the Rootsweb pages. It’s not directly on topic, but it relates to Tanner’s later dogmatism. In arguing for extinction and dismissing post-Singer Tract reports, many of which involved birds being flushed from tree stumps or other locations near the ground, Tanner characterized this behavior as being characteristic of pileateds not ivorybills.

Rootsweb has a newspaper account of  T. Gilbert Pearson‘s  visit to the Singer Tract in 1932. Pearson (who was President of the Audubon Society at the time) was the first ornithologist to confirm the presence of ivorybills in the Tract. He saw, “The birds . . . feeding on stumps of rotting trees, the tops of which had been broken off. A favorite place for feeding is also on dead limbs at or near the tops of the very tall sweet gum trees found abundantly in this region.”

The evidence that relates directly to Tanner’s study area and its immediate environs suggests that claims about “virgin forest” and IBWO dependency on old-growth are based on flawed premises. The Singer Tract was no doubt a remarkable place, a huge area of contiguous and relatively undisturbed forest, but it’s clear that much of it was not old growth or “virgin”.

It’s more useful to think about what the Singer Tract is likely to have offered Ivory-billed Woodpeckers – some measure of seclusion, enough big trees for roosting and nesting, and an abundance of standing and fallen deadwood. The myth that the Ivory-billed Woodpecker required vast tracts of “virgin” forest may be emotionally compelling, but it’s not based on evidence; it’s time to put it to rest.

I’m looking forward to spending a week in the field starting just after Christmas.

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Tanner and Population Density

I recently gave a talk to the Rockland County Audubon Society, and a member raised what I think is the strongest question about our evidence and about the persistence of the Ivory-billed Woodpecker in general. “How could the species have survived in such low numbers and at such low densities?”

In other posts, we’ve pointed to evidence that Tanner missed a population in Mississippi and was somewhat cavalier in his approach to evaluating potential habitat, disregarding advice Herbert Stoddard gave him in 1936, “The area where they (Ivory-billed Woodpeckers) may occur at present is simply tremendous, not restricted as many believe.”

A recent study on Magellanic Woodpeckers points to another factor that raises even more doubt about Tanner’s estimated population of 22 in 1939.  The study was conducted in an old growth Lenga forest in Patagonia. According to this study: “Our results show that Magellanic Woodpecker family groups require a minimum of 100 ha in old-growth forest habitat; thus, forest patches in less favourable forest conditions (e.g., younger, managed, fragmented, mixed forests) should probably be much larger to support a resident pair or family.”

The specific criteria that Tanner used for estimating the 1939 population at approximately 22 are unclear, but he assumed a maximum carrying capacity of six square miles per pair. The Wikipedia entry on the IBWO is even worse and is generally rife with bad information; the editors there expand Tanner’s six square miles to “9.7“.  Elsewhere, Tanner suggested a minimum home range of two and a half to three square miles. These numbers are somewhere between six and 16 times the minimum for a large southern congener that, like the ivorybill, lives in more temperate habitat than others in the genus.

Thus, there is a strong possibility that Tanner severely underestimated ivorybill populations in Florida. If he was so badly wrong about home range, he’s more likely to have missed populations in areas that he rejected for being suboptimal and not expansive enough.

Double the minimum acreage required by the magellanic in optimal habitat and apply that number to the ivorybill, and Sherburne, a large Louisiana WMA, could theoretically be home to just under 90 family groups. (We don’t think this is the case.) Even at 450 hectares per family group, the carrying capacity in Sherburne would be nearly 40. Such numbers are improbable in the extreme, but 9 or 10 family groups in an area that size would be very hard to detect.

With significantly smaller home range requirements, a substantially larger population in 1939, and a recognition that Singer Tract-like conditions are not a requirement (as Tanner himself made clear), various survival scenarios become considerably more plausible, assumptions about low densities become more questionable, and the quantity of potential habitat is far greater than anyone has imagined.

Edited to add: Although the study referenced above is more recent, Noel Snyder made the same basic argument about magellanics and other congeners in The Travails of Two Woodpeckers (2009). Snyder posits that hunting pressure, not habitat loss, was the primary cause of the ivorybill’s decline.

Snyder (who to the best of my knowledge has little hope for the ivorybill) does not fully address how Tanner’s assumptions might have affected his population estimates and habitat evaluations. He also doesn’t consider how taking Tanner at face value has influenced both search protocols and the “credibility” of post-Singer Tract reports. Nevertheless, he does hint at what I suspect is the key to the species’ survival: “With food supplies degraded, not eliminated, a reasonable possibility appears to exist that many ivory-bill populations in logged regions might still have found enough food to persist and might have endured at modest densities, had they been free of shooting pressure. The long persistence of the ivory-bill in one quite thoroughly logged region in Cuba supports this possibility . . .”

In my view, Snyder goes a little too far in downplaying specialization as a factor, even if Tanner overplayed it. It’s pretty clear – from range, habitat, and morphology – that ivorybills are more specialized than pileateds. But if the IBWO did persist after World War II and Snyder is right that hunting was a major factor in the species’  decline (even in the Singer Tract), there may be even more room for optimism, since hunting practices changed considerably in the post-war era.

 

 


Trip Report November 23-28, 2015, Part One

This post will be something of a departure from previous ones in that we’re writing it jointly.

Though we met in 2008 and started calling our effort “Project Coyote” in early 2010, in many ways this week marks the 6th anniversary of our collaboration. It was the first time we visited the old search area together and everything grew from there. We’re an odd couple, with very different cultural backgrounds, personalities, and worldviews. There have been many strange ups and downs over the years but remarkably few major disagreements. One thing we’ve shared from the start is a similar approach to putting the pieces of this puzzle together – trying to glean what knowledge we can from those who were able to find ivorybills in the past, especially J.J. Kuhn. We think we’re on the cusp of obtaining something definitive for reasons that should become clearer in the post, if they aren’t already.

It’s remarkable that we’ve come this far. The obstacles involved in documenting the ivorybill are enormous. We’re just two individuals with limited time and resources searching in a fairly large, remote, and challenging patch. We have a small circle of supporters and trusted people who visit our area when time allows.

There are huge swathes of potential habitat in the southeast that get little human traffic, especially outside of hunting season, and many of these have not even been considered, let alone visited. It’s not uncommon for foreign (and some domestic) ornithologists to assume that conclusive imagery should have been obtained by now, just because it’s the US and birding is popular here and that extinction is likely because several organized searches have failed to come up with something definitive. Many American birders with little knowledge of or experience in the rural South jump to similar conclusions.

The mere fact that there have been formal, funded searches matters very little. The difficulties in obtaining documentation of an extremely rare, wary bird species that requires a large home range in secluded, difficult habitat are monumental. We think that camera traps are the most promising avenue for obtaining something conclusive (as is frequently the case with cryptic animals). The problem has been to place the cameras in a location that birds are likely to visit. This has been our approach from the start, but it’s only now that we think we’ve solved the problem. While we will continue to use other methods and to host visiting biologists and trusted supporters, camera traps will be our primary focus in the coming months.

On November 23, we were joined by Travis Lux, a freelance radio reporter who contacted us a few months ago and who has promised to keep our location confidential. We visited the downed sweet gum top discussed in several previous posts, most recently this one, and were elated to find that there was some new scaling at the top of the snag and decided that we’d return to Frank’s house to review the footage.

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Fresh Scaling on Downed Sweet Gum Top

As soon as we looked at the data stored on the card, our elation turned to alarm and then almost to despair. Travis had been recording the whole day, and we’re sure this will make for some dramatic radio. Frank will pick up the narrative to explain.

Trying to understand what “goes wrong” with the various types of game cameras is a guessing game. Of the three cameras that we had deployed, two of them – upon reaching the 32 gb storage limit on the cards – began to overwrite the files rather than shut off automatically (as the instructions imply but do not directly state they should). The instruction manual was also misleading about the duration of a deployment based on the delay time set by the user. The instructions implied that a 32 gig card would not be completely full at the end of a 60 day deployment.

In reality, the card filled up after fifteen days. The camera continued to operate, but it overwrote the earliest files with the newest files, rendering the earlier files unrecoverable. With this hard learned bit of knowledge, I increased the time lapse to ten seconds, from five, and cut out about 45 minutes of “on” time at each end of the day.

According to the data gathered thus far and calculating data storage capacity vs. time deployed and time lapse setting, this SHOULD give us about 45 days with 50% battery and a fresh 32 gig card. The reprogrammed camera that we pulled the card on Mark’s last day in the field appeared to bear this finding out.

With very few exceptions, these cameras are manufactured and assembled in The People’s Republic of China. The instructions (and this has been true of several different brands we’ve tried) are generally translated from Cantonese or Mandarin…Poorly. Fractured syntax, and confusing usage of common words often leaves the guy programming the camera guessing what the instructions REALLY mean.

One of the cameras shut itself down for unknown reasons after taking just a few images. When checked, the batteries were still above 90%. I put a new card in it and conducted a 30 minute field test; it seemed to be functioning properly. Of the four cameras and three locations where we now have cams deployed, this one is in what we feel is the least likely to be visited by woodpeckers in the near future. Hopefully, the glitch will not reappear.

To add to Frank’s comments, unless one has well over $1000 to spend per unit, there are major tradeoffs involved in selecting trail cams. The brand we’ve selected stores individual frames as the equivalent of deinterlaced video stills. This allows for greater storage capacity and longer battery life but lower image quality, especially at a distance. Fortunately, all of our current deployments are at close enough range to produce a definitive image or series of images, and we now know that the cameras themselves do not scare off whatever is doing the scaling, something we thought possible in the past.

To return to the main topic, after the initial shock and disappointment wore off, we realized that there had in fact been relatively little scaling, except at the very top of the downed crown. The main trunk is almost untouched, and return visits remain a strong possibility. We have redeployed the camera and will leave it in place indefinitely.

Tuesday the 24th was a more encouraging day. We were joined by Tom Foti, formerly of the Arkansas Natural Heritage Committee and a member of the Ivory-billed Woodpecker Recovery Team’s Steering Committee. Tom is perhaps the foremost expert on bottomland hardwood ecology. He was very impressed with the habitat. He jokingly commented that if he were still with the Arkansas Natural Heritage Committee, he’d try encourage his state to annex the area.

While we were unable to show Tom any feeding sign, we did hear a couple of possible double knocks. In addition, we found a recently dead small sweet gum that had apparently been killed by ambrosia beetles, similar to others we’ve found, but as yet untouched.

While there’s no suggestive feeding sign in the immediate vicinity, the location is approximately a mile from the camera deployment discussed above and a few hundred yards from where we recorded an apparent double knock and obtained several intriguing game cam images. Given the absence of recent scaling in the immediate vicinity, we think this is the least promising of the three current locations.

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We called it a day early because Tom had to return to Arkansas. What he saw and heard left him enthusiastic and eager to return. It’s a privilege to be around someone who’s so knowledgeable, and we look forward future visits and to learning from him.

If the 24th was a good day, the 25th was even better, though considerably more challenging. Brian, Frank’s son, came along and helped carry some of Frank’s gear. We went into an area that we’ve only visited once before. The area is approximately 1.5 miles from the nearest road, and as it turned out, we did that three mile round trip twice.

The habitat in this part of our patch is magnificent. There’s a good deal of old scaling high on live sweet gums. While this isn’t the type of work that we consider highly suggestive, it is consistent with what Tanner described and photographed (more on Tanner in Part 2).

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Old High Branch Scaling at Lower Left and Center

We found a huge and recently downed (leaves attached) sweet gum, part of which fell between two recently dead saplings that both showed signs of ambrosia beetle infestation. Some  of the scaling on the huge downed gum seems consistent with Pileated work (having a layered appearance), and some of it comes close to what we think is diagnostic for ivorybill. This is the first freshly dead tree we’ve found that has feeding sign suggestive of both species.

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This Huge Sweet Gum Blowdown Shows Sign Suggestive of Both Ivory-billed and Pileated Feeding.

After finding the sign, we decided the location merited our deploying two cameras. (It would take four or five to cover the whole blowdown.) Brian and I hiked out to retrieve the two that Frank and Bob Ford deployed in October, while Frank went back to his house to get additional cards. We hiked back in and reached the location at around 3 pm.

Over the next hour, we heard several double and single knocks that seemed to be coming from no more than three hundred yards away. A couple of the double knocks were what we consider the best (most Campephilus-like) we’ve ever heard.

It was getting late, so we hiked out as quickly as we could, stopping to rest a little before sunset. As the sun was going down, there was a small burst of shooting from the direction of the road. A PIWO started scolding in apparent response, and Brian and I heard a sharp single knock from the direction of the bottom (away from the shooting) and more distant than the squalling pileated. (As an aside, Frank is a very experienced hunter and can easily distinguish between shots and knocks. It’s not difficult for me either, except when the sounds are obscured by crunching leaves, etc.)

We now have all four cameras deployed on recently dead trees or parts thereof that have a good chance of attracting woodpeckers in the near future. This along an approximately three mile line, with about a mile between each camera.

To be continued . . .

 


Part Two – Frank’s Report from the Field: October 9-11, 2015

Day 2 – October 10, 2015

We have only visited the southeastern quadrant of our “northern sector” four times. This is mainly due to the amount of time it takes to cross about a mile and-a-half of the uplands surrounding the bottom. Bob and I decided we would try a longer, but possibly quicker and easier, approach by following a fire lane that is maintained a couple of times a year. It was a pleasant, if boring, hike of about a mile and three quarters, a little further, but much easier going to get to the edge of the bottom.

The forest on this side of the stream is of a somewhat different composition than that on the other side. As well as the sweetgums, loblolly pine, and various Quercus sp. an appreciable percentage of the trees are mature 3′ DBH or more beeches.

A Beech with a not-particularly-interesting large (6

We made our way to the main channel with relative ease – this quadrant of the forest seems not to have as many deeply incised sloughs and secondary channels, so the temptation to just keep moving slowly is irresistible. After reaching the main stream, we began to do half-circle transects, looking for anything interesting. We finally took a break about mid-morning, and I performed an ADK series and shortly thereafter a series of playbacks. We then sat quietly for about thirty minutes.

We were separated by about 15 yards, and Bob was sitting at the bottom of a large tree facing away from me. Before we continued on our way, we compared notes, and we had both heard two double knocks, and possibly one kent call. Kent calls, what are and what aren’t, have been debated ad nauseum for years. Suffice it to say that this one, though further away and not as loud, stood out from the Jays that were making a ruckus all around us. All we could say for sure is this one was “different” in a way that’s hard to describe.

We continued on, finding our way back to the bank of the main channel every so often. The stream is dryer than I’ve ever seen it.

At one point, I came upon a series of curves, which being a bit deeper, allowed the water to pond. It was not running and none too fresh, but it was water. I noticed these two turtles on a log, probably a slider of some kind and a cooter. They seemed to be annoyed at one another.

Turtle Fight

We continued easing through the forest, moving slowly and stopping to listen and look occasionally. I photographed Bob standing next to a large swamp chestnut oak.

bob tree

We found a bit of intriguing scaling here and there, but no large concentrations. This dying sweetgum snag is a good example. (Note the large insect at the upper right. We have not been able to identify it.)

new scaling

At about one o’clock, we’d just kept walking through “lunch hour”, we decided to take a break. While we were snacking and rehydrating, I performed another series of ADKs followed by playbacks. After about an hour, Bob and I once again compared notes, and once again we had heard a pair of kents, and a single DK. I have to note that nothing we heard appeared to be a direct response to the recorded kents of the anthropogenic double knocks. While I was sitting there, I made this picture of a Red-headed Woodpecker.

red head

We finally came to a corner with an adjoining piece of private property. As the property line was on a direct bearing for the truck, and was “only” a mile through unexplored terrain, we decided to take a chance even though terrain sometimes imposes obstacles. Fortunately for us (we had covered about six total miles previously) the terrain wasn’t bad at all, and other than a couple of hills to climb, the walk was pretty easy. On the way home, we stopped and picked up dinner at a local BBQ joint that has become something of a Project Coyote tradition.

Day 3 – October 11, 2014

On the way to the search area this morning, Bob and I, feeling a bit peckish, decided to stop at one of the convenience stores on the way. We were a bit mystified to find this sign in the window:

Fried Chick

Being a proud son of Louisiana, I’m well aware of our love of foods that are considered a bit, ummm unconventional, but even I was a bit taken aback at the prospect of frying chicks…

We arrived at our entry point about ten minutes after first light and headed into the forest. This particular area Mark has discussed a number of times – a couple of hundred yards from the parking area one encounters a tornado blow-down track that is approximately 400 yards wide. This area is unbelievably difficult to traverse – large boled trees scattered like a giant’s game of pick up sticks, thick, almost impenetrable thickets of new growth, blackberry vines and saw briars, as well as the usual random sloughs, and cutoff stream channels.

It took us nearly an hour to make the half-mile to the location of the snag where photos, discussed in previous posts by Mark, were taken. My express purpose was to place one of our new Plotwatcher Pro cameras in this location. New growth of limbs and underbrush made this deployment a bit more complex than the last time. Bob trimmed intervening vegetation while I programmed, set up and started the camera.

After all this work, I used the camera’s Aimcheck function to make sure that the cam was placed optimally. We then proceeded to follow the bank of the main channel downstream. It should be noted that the stream is not running. In all my years of coming to this area, as a hunter, and searching for ivorybills, I have never seen it this dry.

We came to a familiar ponded slough where Mark and I have often stopped and rested for a few minutes. One of the larger trees, a 3.5 ft. DBH water oak had blown down since the last time Mark and I had visited the area in April. The tree still had leaves on it, though they were dry and brown, and the bole and upper branches had no sign of woodpecker workings. I believe that this tree was blown down on or around July 4th as that was the last time severe weather passed through the area. As they are very light and easy to carry, I had an extra Plotwatcher Pro cam with me. Taking advantage of this opportunity, I deployed the camera with a good view of the bole and top – hopefully this tree will attract insects, and soon thereafter woodpeckers feeding on them.

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Frank Wiley examining a cavity through binoculars next to downed water oak at new camera deployment location.

Bob Ford standing next to ~20' root disc of downed water oak

Bob Ford standing next to ~20′ root disc of downed water oak

Bob and I continued upstream for another half mile, located a nice spot with a good view, and I performed an ADK series, followed about ten minutes later by a series of electronic playbacks of Singer Tract ivorybill calls. Shortly thereafter, Bob heard a double rap drum, that was captured on my digital recorder. I personally don’t believe that the drum was a direct response to my ADKs as there was at least a fifteen minute interval after the last of the ADK/playback series.

The double rap is not “perfect” in that the “intra-knock interval” is about .05 seconds longer than the “ideal” – based on averages of the intervals of other Campephilus drums – but it sounds very good.

bobs dk

As we were leaving, I determined to blaze a better trail through the blowdown area. Following a straight bearing on my GPS, I used a hatchet and snips to carve a path through the heavier ground cover. Perhaps crossing will be a bit easier next time.

On the way out of the forest Bob and I were treated to one last encounter. We came across this Buttermilk Racer sunning itself on the road. While not endangered, this snake is uncommon and seldom seen. After taking a few photos of him, I tapped his tail with my foot, encouraging him to seek a safer place out of the roadway.

Racer2

Racer1

Buttermilk Racer

I really enjoyed Bob Ford’s visit – he is a skilled woodsman and birder, and his insights as a professional wildlife scientist are greatly appreciated. I am looking forward to Mark’s next trip – hopefully over the Thanksgiving holiday.

Also, Mark and I would like to thank The Rapides Wildlife Association, and another donor “MC”, for their much appreciated and unsolicited assistance in purchasing our new trail cams, memory cards, and batteries.

A note from Mark: Frank captured some of the possible kent calls on his recorder. They are faint, and it may not be possible to tease any detail out of them. He may do a follow-up post if anything of interest can be gleaned.


Feeding Sign, Foraging Preferences, and Prey Species: Some Observations and Speculation

Frank and a visiting ornithologist spent this past weekend in our search area. I’m eager to read and will be posting Frank’s report before long. For now, suffice it to say they set up three trail cams, one on the snag where we captured the image discussed here and here and one on this downed sweet gum top found in April:Big Limb

It most likely fell on April 19th. When I found it a couple of days later, it had fresh green leaves attached and no sign of insect infestation. Since then it has been partially scaled. This is an important data point, as we know the scaling took place within five and a half months of death, and Tanner documented the IBWO’s preference for freshly dead wood. We hope there will be a return visit soon.

They also placed a camera on an even more recently fallen water oak, something that started me thinking about possible patterns in the feeding sign we’re finding.

I’ve counted the examples of feeding sign from our current search area I’ve posted on the blog (which is by no means all the suggestive work we’ve found but is generally the most impressive), and the results for sweet gums are interesting, especially in light of Tanner’s observations suggesting an IBWO preference for sweet gums. Our results also suggest a preference for hickory. (Hickories were scarce in the Singer Tract, and apparently the species present in our area were not present there.) In both cases, the frequency with which we’re finding scaling seems to exceed the relative abundance of either type of tree, although we have not made formal counts. This sign was found between the spring of 2012 and the Spring of 2015, except for the downed top pictured above, which was scaled a little later.

The tally includes a couple of examples of work that falls short of what we consider to be diagnostic for IBWO. It also includes the small sweet gum snag that looks like it was attacked with a hatchet.

HackedGum2

While there seemed to be a preference for sweet gums prior to the 2014-2015 season, the preference was considerably more pronounced this year when the abundance of fresh scaling on sweet gums in a relatively small area was astonishing. Here’s the multi-year breakdown:

Sweet gum:                       25

Hickory:                             10

Presumed sweet gum:        6 (One example possibly PIWO)

Oak species:                       3

Willow oak:                          2

Unknown:                            1

Maple:                                  1 (Possibly PIWO)

Ivorybills fed on sweet gums in 42.6% of Tanner’s observations, scaling in 40 instances and digging in 3. Sweet gums made up 20.8% of the forest composition in Tanner’s study area. Next on Tanner’s list of preferred foraging trees were Nuttall’s oaks. By contrast, Pileateds “appeared to have no preference for any species of tree.” Tanner observed PIWOs feeding on sweet gums on fourteen occasions; nine involved digging and five involved scaling. He further noted, “What scaling Pileateds were observed to do was mostly on loose bark and was never as extensive or cleanly done as the work of the Ivory-bills.”

On a more speculative note, I think I’ve been able to identify one species of beetle that’s infesting the sweet gums, including the small one shown above. They’re an invasive, the granulate (formerly Asian) ambrosia beetle Xylosandrus crassiuculus (or another closely related invasive). Ambrosia beetles are tiny, but they are gregarious, with adult females creating chambers and tending broods of larvae in the sapwood. They can kill small trees but also infest larger ones. They have a relatively short life-cycle, and one source suggests they can produce 3 or 4 broods a season in the deep south. It’s worth repeating that I’ve seen signs of ambrosia beetle infestation elsewhere in Louisiana (near our old search area and in upland hardwood forest adjacent to our current one) but did not find work suggestive of ivorybills in either place.

We’ve found known IBWO prey species in our search area, on trees that we suspect were fed on by ivorybills. We also suspect that, contrary to Tanner, they may feed on darkling beetles. Could they also be feeding on an invasive species? We can see no reason to suspect otherwise and will continue our investigations with this in mind. I plan to return to Louisiana Thanksgiving week.


George and Nancy Lamb’s 1957 Cuban Ivorybill Study

I have been re-reading George Lamb’s 1957 report on the Cuban Ivory-billed Woodpecker. A number of items struck me as potentially significant for North American searchers, some for how they diverge from Tanner and others for their level of detail. Since this report is likely unfamiliar to many, I thought I’d do a quick post listing some of the more interesting observations

Lamb references a number of local sightings of “groups” of ivorybills, with one report to John Dennis that involved six birds. Notwithstanding, Lamb estimated the population density in Cuba to be much thinner than in the Singer Tract, at one pair per 12-25 square miles. He also pointed out that “ . . . the Cuban Ivory-bills are living for the most part in a cut-over pine forest where only small and deformed trees remain.”

The Cuban ivorybills fed on pines and hardwoods more or less equally, although most of the feeding sign was found on pines, due to the difficulty of searching for sign in the denser hardwood habitat. Roosts and nests were found exclusively in pines (one unused cavity was found in a hardwood), which is interesting in light of the fact that hardwoods were also available. Cavities were found at heights ranging from under 20 feet to nearly 60 feet. Cavities were higher in mature forest; Lamb suggested but did not conclude that the preference was for higher cavities and that the lower ones reflected an adaptation to cut-over conditions.

Lamb describes a female scaling bark: “At this point she was only about 25 feet away while she was feeding around the base of a small pine. She began ‘barking’ this tree about 30 inches from the ground and slowly worked up to the top.” Dennis too had observed birds scaling small pines. They found more scaling than excavation.

This apparent preference for pines, including small ones, may be significant, particularly since the hardwood areas were “relatively untouched”.

An estimated 17 birds were killed by humans over a ten year period, a huge number for such a small population. And it seems an open question whether the thinner population density noted by the Lambs was due to habitat quality, hunting pressure, or a combination of the two.

Regarding flight style: “. . .the flight of the Cuban Ivory-billed Woodpecker was always level and purposeful. They are strong fliers, capable of covering considerable distance in little time, as indeed they must to live successfully in cut-over woodlands. Although the Ivory-bill did not seem to undulate in its flight, the wing beats were not steady, having an almost imperceptible 2-3-2-3 rhythm.”

There’s no mention of double knocks, but calls are discussed. Lamb describes the sound as like the “note of a penny tin trumpet . . . short and usually repeated in a series of single-double-single beats, or it may begin with a double call: that is a high nasal “pent, pent-pent, pent”, or just “pent-pent”. On several occasions the female Ivory-bill most frequently observed made a few long and very loud calls, soon after leaving here roost tree in the early morning. The notes were of greater duration than normal and were repeated in a series of sixteen to twenty-two kients.”

Food for thought . . .


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

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

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

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

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

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

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

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

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

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

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

Frank Wiley with massive sweet gum

Frank Wiley with massive sweet gum

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

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

Old scaling with large exit tunnels

Old scaling with large exit tunnels

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

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

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

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

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


Trip Report – November 27-30, 2014

Frank Wiley and I have spent the past four days in our search area, beginning on Thanksgiving morning. Before getting into the details, it merits noting that this weekend is the probably the peak of deer season in Louisiana. On Thanksgiving, there were perhaps fifteen or twenty people hunting on the edges of the habitat corridor. We encountered a single person in a tree stand that day, at the edge of the potential habitat. The number of hunters dwindled over the weekend, and on Sunday morning, we heard only one or two distant gunshots and saw a lone pickup truck parked along the parish road, nowhere near the bottomlands where we’re focused. On Thursday, we visited the southern sector, where we’ve spent the most time and have had the most encounters, calling it a day in late morning for Thanksgiving. At dinner, a long-time acquaintance of Frank’s described seeing IBWOs at a location about 10 miles from our search area from which we’ve had another credible-seeming report. We spent Friday through Sunday in the northern sector, which contains some extraordinary habitat, much of it old growth or nearly so. In this sector, sweet gums and oaks of 3-4’ diameter at breast height are not uncommon, and larger trees, like the one pictured, can be found from time to time.

Frank w:Chestnut Oak

Frank Wiley with Chestnut Oak. His arm is 32″ from armpit to fingertip. We estimate the DBH to be 5′.

Travel in the northern sector is extremely challenging due to blowdowns and deeply incised sloughs. On Saturday, it took almost the entire day to cover a total of three miles. One impressive feature of the area is the presence of large patches of cane that reaches as much as 15’ in some places. In some parts of the forest, cane is the main component of the understory.

Frank Wiley in Cane Brake

Frank Wiley in Canebrake

Cane understory in second growth pine flat

Cane understory in second growth pine flat

It appears that some places within the northern sector have not been visited by people for several decades. In one apparent old growth area, the only litter we found was a Schlitz beer can and a 16 ounce glass soda bottle, both of which date to the 1980s. There were no shotgun shells or other signs of human presence to be found. Approximately 1/4 mile south we did find a hunter’s flagging that was several years old. This is difficult and seldom visited territory.

At 8:40 on Thursday morning, we heard some distant, intriguing kent-like calls. There were, however, several Blue Jays calling much closer to our location. We then visited the tree shown on the Project Coyote homepage that we found in May 2013. The decay is progressing, and there are many new insect exit tunnels through the remaining bark. It seems significant and mysterious to us that there is no sign of further woodpecker foraging of any kind on the tree. This tree is in within a known Pileated Woodpecker home range, and we believe that if the work were that of a Pileated there would have been multiple return visits by now.

Old feeding sign that has the appearance of the work we believe to be diagnostic is abundant in the northern sector, but we did not find anything that appeared to be fresh. We suspect this may be at least in part a seasonal factor and that scaling of bark is a more central feeding strategy during mating season and until young have fledged. Nonetheless, we were impressed by the abundance of feeding sign. These are several examples. We found the excavation in the last image to be somewhat different from typical Pileated Woodpecker work and therefore somewhat intriguing, although we suspect it was done after the bark had been removed. The wood showed no signs of rot. Oldscaling Old Scaling HiRes Oldscaling2HiRes

Two examples of old scaling found in the northern sector

Examples of old scaling found in the northern sector.

Unusual excavation in a scaled snag

Unusual excavation in a scaled snag

We did not hear anything intriguing on Friday, but at 1 pm on Saturday, deep into the remote, untraveled area, we heard two ambient double knocks. The first of these was perhaps the closest to recorded Campephilus DKs I’ve ever heard in the field. Frank heard an additional DK or two that I missed. We then got two or three single knocks in response to a series of ADKs (anthropogenic double knocks). These knocks appeared to come from two sources, moving from slightly northwest of our location toward the south. On our way out of the area, we found an old snag with an intriguing cavity, as well as one being used by a sub-adult Red-headed Woodpecker. We returned on Sunday morning to place a game camera on the tree. At approximately 8:15 am, prior to setting up the camera, we did an ADK series (this within 200-300 yards of where we heard the DKs the afternoon before). We had several knocks, both single and double, in apparent response.

Red-headed Woodpecker peering out of cavity

Red-headed Woodpecker peering out of cavity at top of target snag

Cavity11:29:14

Cavity in the northern sector found November 29, 2014. Camera trap placed November 30.

As peak search season approaches, we’re encouraged to have three distinct but connected areas where we’ve found suggestive feeding sign and have had putative encounters. While there have been no sightings in the northern sector, the contact rate is extraordinary, as is the abundance of feeding sign. To be continued . . .


Habitat Conditions in the Singer Tract

Late last year, I wrote a post entitled “More Minutiae – Habitat Quality and Population Density in the Singer Tract”. I had to follow up with a couple of corrections and elaborations based on insights others shared with me. In the interest of providing more clarity and coherence, I thought I’d do a new piece combining the three posts and expanding on them a bit. I won’t delete the originals, but this one reflects what I think is a more accurate understanding of the material involved.

Mack's Bayou Ivorybill nest tree. Courtesy of the Division of Rare and Manuscript Collections, Cornell University Library

Mack’s Bayou nest tree. Courtesy of the Division of Rare and Manuscript Collections, Cornell University Library

The initial post was inspired by the image above and the caption describing it as the “Third ivorybills’ nest”, one I had looked at but not closely until last year. When I did examine it carefully, I was struck by how open the surrounding area seemed to be. Then I started going through archival photographs and scrutinizing them a little more closely.

In browsing through the Louisiana Digital Library’s collection of Singer Tract photographs, I came across an image that I had missed, one of the bridge over John’s Bayou taken in 1940. Tanner (p.32) includes an ivorybill sighting from this immediate vicinity, just northwest of the bridge. What I find interesting about the photograph is that the forest along the road appears to be fairly even-aged and does not have the characteristics typically associated with old growth. It is similar to what can be found in many parts of Louisiana today. An image from along Sharkey Road taken in 1937 shows similar characteristics, although another shot from 1939 (probably taken east of the bridge) shows more impressive looking habitat.

Richard Pough wrote a follow-up report to the Audubon Society on the Singer Tract in 1944. It’s a very interesting document that raises some questions about Tanner’s work. Pough explicitly accepted “Tanner’s premises as to the feeding habits and habitat preferences of the ivory-bill”, but he also noted “[n]othing in Mr. Tanner’s study indicates that Ivory-billed Woodpeckers show any preference or marked dependence on trees of great size such as one would find only in a virgin forest. He found them doing 14% of their feeding on trees 3”-12” in diameter and 64% on trees under 24” in diameter.”

Pough pointed out that “Maps of the area as of 1846 showed much of the Tensas River in plantations and many cleared fields back from the river on some of the interior ridges. This development continued for another 20 years until the Civil War, by which time Madison Parish was producing 110,000 bales of cotton a year. As the Parish has never produced over 30,000 bales since the Civil War, one gets some idea of how much land is now occupied by second growth forest of approximately 80 years age.”

Pough found only one ivorybill, a female. He assumed, relying on Tanner, that this was the only one left in the Tract. He may well have been mistaken, since Gus Willett, game warden in the Tract, wrote Tanner about seeing a pair in November 1948 (although the exact location is unclear). Correction, Willett did not write the letter, although the report reached Tanner, as discussed here.

The lone bird Pough saw was either the John’s Bayou female or one of its offspring. According to Pough, this bird was probably not feeding in virgin forest, and his report specifically suggests that Tanner might have been mistaken about the maturity of some of the habitat in the John’s Bayou area. In 1941, Tanner had written that the remaining John’s Bayou birds were roosting and feeding in “virgin” timber. Pough’s description of this area (and it seems to be the same patch) suggests it was likely cultivated pre-Civil War. It was devoid of big sweet gums, which Pough deemed to be the best indicator of old growth conditions, but had many dying Nuttall oaks 12-20 inches in diameter. Nonetheless, Pough relied on  Tanner’s premises to conclude that “only a relatively small portion of the total area of the Singer Tract supported a forest suitable as habitat for these birds.”

To return to the material in the earlier blog posts, much of the discussion focused on home ranges and the distribution of nest sites.

This map, drawn by Tanner after the 1935 expedition, lists three nests – designated as nests II, III, and IV –within a mile or two of each other and in the vicinity of John’s Bayou. Nest II is the famous “Elm Rock” nest. The map also shows a tree which is designated “Nest (?) III Squirrel” (also mentioned in Bales, “two miles to the south of the first nest” and fifty feet up p. 45). This was outside the area Tanner designated as prime in 1941 (p. 91); it is approximately a half-mile from the John’s Bayou bridge.

I’ve discussed this issue in depth with someone who’s very familiar with Tanner’s notes. I’m now persuaded Tanner concluded that nests III and IV from 1935 were not nests after all and that he assigned the birds involved to Titepaper (Nest III) and Bayou Despair (Nest IV). Nest IV is apparently one that Kuhn found but was unable to re-locate. Why Tanner changed his mind about it remains a mystery.

It’s very difficult to piece together this fragmentary information, and the monograph muddies the waters a bit by presenting the home ranges of the birds as being quite discreet, perhaps a good deal more than they were in fact. I suspect that Tanner decided the cavities were actually roosts, (although neither one is mentioned in the monograph). If so, they would have been well outside the home ranges Tanner identified and closer to the core of the John’s Bayou range than to the core of Titepaper or Bayou Despair.

Nests I and V were located near Mack’s Bayou. Nest I is dated May 14, ’34 on the map, and Nest V is dated May 10, ’35. The ’35 nest failed. It is the one referenced above. Allen and Kellogg described it as being 45’ feet up, in a pin oak snag, in a natural clearing, although it has been suggested that the snag may have been a remnant large tree in area that had been cleared prior to the Civil War. The nest designated Nest I and dated May 14, 1934 appears to be the one Tanner described on p. 81 of the monograph, “located within 100 yards of the second nest found in 1935”; however, in the monograph, he gave the date as May 13, 1933.

It’s worth pointing out that the Mack’s Bayou nests were in an area that Tanner designated as “best” for ivory bills (even if it’s not clear whether it was truly old growth). Nonetheless, nests failed in 1933 and 1935, and the adult birds had disappeared by 1938, apparently after producing one fledgling in 1936 or 1937. This was before the logging began.

My intention in writing those initial posts was to get a clearer handle on population densities and habitat requirements in the Singer Tract. In retrospect, I’m not sure that’s possible, since Tanner’s observations were almost entirely limited to one family of birds in a population that was dwindling for unknown reasons. At the very least, Tanner’s statement that 7 pairs of birds required 120 square miles of virgin forest in 1934 is based on an inflated estimate of the amount of old growth in the Tract and his minimum estimate of 6.25 square miles per pair also rests on that flawed premise.

Pough observed, “ . . . the ivorybill problem puzzles me exceedingly, and I do not feel that Tanner’s report begins to explain the reasons for the drastic decline in this species.” As the 2014-2015 search season approaches, I can only hope that the question of how the species persisted will puzzle people exceedingly in future years.