Remembering Frank Wiley on the Anniversary of His Passing

Last year, a reader requested that I post some personal reminiscences about Frank. I didn’t get around to doing it then but thought I’d offer something on this sad anniversary.

Frank and I met through the Ivorybill Researchers’ Forum (www.ibwo.net) in the fall of 2008. I made my first trip to search with him in Louisiana shortly thereafter. Our collaboration gelled in the summer of 2009 when he began to visit our old search area. I visited him again in November 2009. In January 2010, I came up with the name Project Coyote as a play on his name and to reflect his central role in the effort.

On the surface, Frank and I were probably as different as the worlds in which we grew up. Frank was one of the smartest, most paradoxical people I’ve ever known. He was a very well-read autodidact whose writing style was deceptively at odds with the way he presented himself – as a stone cold, 2nd amendment loving, libertarian redneck, albeit a nerdy math, physics, sci-fi, and Star Trek loving one. I’m a very liberal New Yorker of Jewish ancestry with degrees in law and American Studies.

Despite our differences, we found more common ground politically than I could have anticipated, and he’d sometimes say, “Don’t tell anyone I said this, but . . .” We shared a distaste for spectator sports and also found common ground musically. Though he loved Pink Floyd first and foremost, and I grew up in the ’70s Punk scene, we both enjoyed rootsier genres, and some of our most enjoyable, non-field times involved tequila and singing together. Frank was a good singer and gifted all-around musician; I managed to harmonize decently on background vocals. The Stones’ “Dead Flowers” was a favorite.

But what really united us was the ivorybill, and more specifically, a shared sense that figuring out what J.J. Kuhn knew was the key to documenting the bird.

While there are echoes of the Tanner-Kuhn dynamic in our story – at least to the extent that, like Tanner, I’m from New York, with a graduate degree from an Ivy League school, and Frank, like Kuhn, was from Louisiana with no formal academic training – we were doing something different. We were equal partners, trying to solve a mystery together, bringing different, complementary skills to the effort.

Still, when we were approached about the possibility of doing a reality show (I’m thankful every day that didn’t happen), I described us as “the odd couple of the ivorybill world”.  In retrospect, the oddness was more superficial than substantial; we may not have been the only such pair; and odd may be commonplace when it comes to the ivorybill. In any case, I miss my friend, our shared dedication to the search, the music, and our many running jokes – especially the ones about stump holes and the ubiquitous Plate 11.

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What’s in the Cavity? A Possible Second Bird in a Couple of Old Trail Cam Photos

Regular readers are no doubt familiar with some of the images shown below. The “neck bird”, which was photographed in our old search area in August 2009, has been discussed in a number of posts. I think it likely shows a female Ivory-billed Woodpecker, something that became clearer once I satisfied myself that what appeared to be red in the crest (in the wrong place for either Pileated or ivorybill) was likely an artifact and that the crest appears to be all black, as shown in the enhanced image below. The original captures (the first taken a minute before the neck bird appears and the second showing the neck bird) are immediately below that for those who haven’t seen them.

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Processed Detail of Image 1096, August 11, 2009

Years after the capture and probably after the first post about this image in 2014, I noticed that an object suggestive of a light colored bill was visible in both frames, apparently protruding from the lower cavity in the snag to the right of center. While I have shared this information privately with a number of people and did a vague Facebook post about it a couple of years ago, I’ve hesitated to blog about it or discuss it in detail. That changed after I showed it to Jay and Erik before we parted company on my last trip to Louisiana. When Erik suggested that the object might be a vine or some other intervening vegetation, I decided to go back through my files. I discovered that Frank had sent me several additional captures from the same deployment. I examined these frames and found that the apparent bill was absent from all of them.

 

Below are details from frames 1095 and 1096 showing the apparent bill, which changes position slightly from one frame to the next. The time lapse interval between images was 1 minute. Again, the cavity in question is the lower one (below the fork) in the snag to the right of and behind the one on which the neckbird is seen in 1096. These snags are black willows (Salix nigra), and the neck bird snag (with the large cavity apparently being used by a squirrel) fell between November 2009 and January 2010. I’m also posting the close-ups in tiled mosaic format so they can be viewed side-by-side.

For this round of image processing, I used Let’s Enhance, which enabled me to retain a large format for cropped and zoomed versions.

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Detail from 1095 – Note apparent light colored object (possibly a bill) apparently protruding from an bisecting the lower cavity

 

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Detail from 1096, captured one minute later. Note slight change in position of the possible bill.

Next are two details from images captured a few days later. The possible bill is nowhere to be seen. The same is true for the other captures from this deployment. Thus intervening vegetation and artifact can be ruled out.

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Detail from image 2135, captured August 14, 2009. Note the absence of the apparent bill that appeared in images 1095 and 1096 captured three days earlier.

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Detail from Image 2507, captured on August 16, 2009. Again, note the absence of any object in the lower cavity.

To summarize, the following two photos show what appears to be a bill in the cavity:

2009-08-11 7:48 am  (image 1095.jpg)

2009-08-11 7:49 am  (image 1096.jpg – the neck bird photo)

The following photos show a cavity with no apparent bill:

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2009-08-14 6:20 am

2009-08-14 6:21 am

2009-08-14 4:06 pm

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2009-08-15 6:20 am

If this is a bill, it appears to be large and light colored, consistent with Ivory-billed Woodpecker. Both Erik and I noticed that, in frame 1095, a topmost part of the white dorsal stripe also may be visible. When Jay first saw the photos, he was reminded of the Neal Wright photos from Texas. Some images from the Singer Tract also come to mind.

 

Thus, this apparent bill resembles those of known ivorybills in cavities – in size, shape, orientation, and contrast. It is present only in frames 1095 and 1096 (the latter of which shows another possible ivorybill); it changes position over the course of a minute, from one frame to the next. There is no way to be sure images 1095 and 1096 show an Ivory-billed Woodpecker in a roost hole, but these facts, especially taken together, suggest that they may.

When I look back at what transpired in the old search area between August 2009 and November 2010, when the adjoining parcel was logged, it’s extraordinary. I may revisit those events in a future post or two.

For now, I’ll close by tying this into the Bits and Pieces series. The old search area is not one that would be deemed suitable under most habitat models. The images above were captured in a stand of black willows at the edge of a bean field. The other trail cam capture, where I had a sighting, was also within perhaps 30 yards of that field. When I look back at my assessment of the habitat from the time, I think I somewhat naively overstated its quality; however, there was a good deal of dead and dying timber, and it was in close proximity to several much larger habitat patches. If we did indeed capture ivorybills with our trail cams, their presence in this area may point to how the species has been able to adapt to more fragmented habitats.

Thanks to Erik Hendrickson for his input on this post and his help in making it clearer.


Bits and Pieces Part 6: Rethinking Range and Habitat – Implications

If you’ve been following this series (Part 1, Part 2, Part 3, Part 4, Part 5) you know it has focused primarily on preconceptions about ivorybill range and habitat types and how the actual record paints a very different picture from what many of us think we know about the Ivory-billed Woodpecker. As I noted in the most recent installment, if our knowledge of the Ivory-billed Woodpecker were based on the archaeological record alone, we’d think of it as an upland species. Further, we might very well assume that it ranged from the hills of Georgia, to the Alleghenies in Virginia, to central Ohio and west-central Illinois.*

While it may border on heretical to say so, I think there’s a plausible argument that the ivorybill’s range prior to around 1800 extended as far north as the mid-Atlantic states (New Jersey and Pennsylvania on the Eastern Seaboard) and as far north as central Ohio west of the Appalachians. I’m inclined to think this is likely based on a number of accounts including: Peter Kalm (a student of Linnaeus who reported the species was present in New Jersey and Pennsylvania in the 18th-century), Jefferson (1780s) and Nuttall (1840s) who included Virginia in the range, and Gerard Hopkins a Quaker from Maryland traveling to Indiana to meet with the Miami and Potowatami Nations. Hopkins described a female ivorybill at Piqua, Ohio (north of Dayton, elevation 873′) in 1804 (Leese, 2010.)

In addition, there’s the specimen that Wilson reportedly collected near Winchester, Virginia ca. 1810 (Jackson) and the central Kentucky specimen reportedly collected in the 1780s (Jackson, accepted by Tanner in 1989).

November 2021: Edited to add the Wilson record for Winchester, Virginia is apparently erroneous.

As I see it, the tendency to treat these records as suspect is based, at least in part, on post-Civil War or post-Audubon “knowledge” about the ivorybill and its habitat, rather than anything intrinsically implausible about the claims themselves.

At minimum, one of the Ohio archaeological finds dates to the 15th or 16th century, so there’s strong reason to think that the ivorybill’s range extended that far north at the time of contact. North American Native populations began to decline after Columbus’s arrival, and De Soto’s expedition, 1539-1542,  led to the collapse of the Mississippian culture. (De Soto also introduced the hogs that plague the southern forests to this day.) As a consequence, countless acres of formerly agricultural lands throughout the eastern United States were reforested and remained so into the 18th and 19th centuries. There’s little reason to think that the ivorybill’s range would have contracted at a time when the total acreage of potential habitat was increasing.

I’m reminded that tree girdling may have been an important factor. The only counterargument to the foregoing suggestion about the increase in total acreage after De Soto is that Native American agricultural activity declined drastically during that period, so that while habitat acreage increased, habitat quality may not have. Tree girdling and intentional burning likely played an important role in creating good conditions for ivorybills and could conceivably have led to range expansion during the Mississippian period and again temporarily during the first couple of hundred years of European settlement.

Ivory-billed Woodpecker use of girdled trees was noted by several early observers – notably Audubon, Gosse, and Scott (in Florida, later). While researching this aspect, I came across an interesting account from 1840s Central Louisiana, apparently just south of Alexandria (the citizens of that city are described as “chiefly gamblers or cunning speculators, a nest of incarnate devils, who live by cheating the latest comers, and, whenever possible, each other.”) I’m not aware of this account having found its way into ivorybill literature:

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From Echoes from the Backwoods; or, Scenes of Transatlantic LifeCaptain R.G.A. Levinge (1849).

With this as background, I’d like to propose an alternative explanation (or more accurately an alternative group of explanations) for the ivorybil’s decline. If you think, as I do, that the ivorybill has persisted, this may help explain how the species survived and may even provide some hope for its future, even in this era of mass, anthropogenic extinction.

When it comes to the decline and possible extinction, there has been a tendency to look for one or two causes. The IUCN Species Account gives the following reasons:

Logging and clearance for agriculture are responsible for the dramatic decline in numbers and range. These factors are likely to threaten any remaining population. Hunting has also been implicated in the rapid population decline, and it has been proposed that this was the primary cause of its decline, with habitat destruction playing a secondary role, but this theory is contentious (Snyder 2007, Hill 2008, M. Lammertink in litt. 2012).

Tanner emphasized the importance of logging during the post-Civil War era, although several of his data points seem to suggest that ivorybills were disappearing prior to the most active logging dates. He also stated that the ivorybill’s disappearance “coincided at least roughly with a time of active or rapidly increasing logging.” Elsewhere in the monograph, he focused on food supply, and I suspect that this, rather than logging per se was a more important factor in the ivorybill’s decline.

That’s not to say logging was unimportant; it clearly played a major role. To expand briefly on the point Bill Pulliam raised: by the late 19th century, the more adaptable Pileated Woodpecker, had been extirpated in many parts of its range, and many expected it to ‘go the way of the ivorybill’. That didn’t happen, and PIWOs returned to or became more common in many areas (my own included) as farming gave way to suburban development and forested acreage increased as a result. I’d suggest that for the ivorybill, habitat degradation, rather than habitat loss, was what initiated the decline, with extensive logging and then hunting accelerating an already existing trend.

That is to say, a number of additional anthropogenic factors likely played a role in the ivorybill’s decline and dwindling range, especially outside of Florida, where hunting and collecting likely had much greater impacts than elsewhere. Hasbrouck, writing in the 1890s, contrasted the lack of collecting in Louisiana, Arkansas, Missouri, and Tennessee with what was transpiring in Florida at the time. And it’s important to remember that Florida, which retained ‘frontier’ characteristics far longer than other parts of the eastern United States, was ground zero for the killing and collecting of birds – for commercial and ostensibly ornithological purposes. Ivorybills appear to have been more common in Florida than elsewhere by the second half of the 19th century, but it also seems probable that they were far more heavily persecuted there than anywhere else.

I’m hypothesizing that the shrinking distribution was correlated with settlement patterns in the northeastern part of that range and that by the middle of the 19th-century, east of the Mississippi, it had dwindled to the now familiar outlines, such as those shown on the IUCN range map. Screen Shot 2017-12-22 at 3.42.31 PM

The situation west of the Mississippi is somewhat more ambiguous. A specimen was collected at Forest Park, Missouri (near Saint Louis) in 1886, and there are records from west of the map in Texas dating to the early 20th century. Nevertheless, the general trend toward a shrinking range, which was frequently described in the 19th century literature, is clear.

European settlement brought about numerous changes in the land even before wholesale clearing of forests began.

As mentioned briefly in the discussion of tree girdling, Native Americans used fire for agricultural and wildlife management purposes, something that was likely beneficial for ivorybills. As Native Americans were exterminated, pushed out of their original homelands, or confined to small reservations, and as European settlers tried to control or eliminate fires, a significant factor contributing to tree mortality was likely reduced, dramatically.

Fulton’s invention of a commercially viable steamboat in 1807 revolutionized commerce, drastically accelerating the clearing of log jams from many watersheds in eastern North America. It’s fair to say that “widespread removal of instream wood for steamboat routes, timber rafts, and flood control was equally significant in decreasing floodplain sedimentation and river complexity, and in causing a fundamental, extensive, and intensive change in forested river corridors throughout the United States.” (Wohl, 2014.) As with changes in fire regimes, this clearing of log jams likely led to a decline in the number of stressed and dying trees along the riparian corridors that seem to have been so important for the ivorybill.

Perhaps equally if not more important in my view is the extirpation of the beaver. It is almost impossible to overstate the role of the beaver in shaping ecosystems throughout North America, a subject that’s addressed in engaging detail in Frances Backhouse’s Once They Were Hats. Beavers help create conditions that are good for woodpeckers by stressing and killing trees, through foraging and by changing hydrology. I’ve never tried to quantify it, but many, perhaps most, medium to large sized sweet gums in our search area show signs of beaver damage, and many others have been killed or severely weakened by beaver-caused flooding.

While beavers are not native to peninsular Florida, the ivorybill’s dwindling range elsewhere roughly tracks their decline; with extirpation starting in the northeast, moving West, and then South. (Southern beaver pelts were less valuable.) By 1900, beavers had disappeared from most of the southeastern US, and in Tanner’s day, a very small population persisted in the Florida Parishes of eastern Louisiana. Reintroductions began in the 1950s, and beavers are now considered a pest animal in Louisiana. It’s worth pointing out that the introduced beaver population in Tierra del Fuego appears to be benefitting the native Magellanic Woodpecker (Soto et al. 2012).

The resurgence of the beaver throughout the southeastern US is almost certainly producing substantially improved habitat conditions in many places. While the old growth forests may be virtually gone, it’s not inconceivable that ivorybill food sources are considerably more abundant now than they were in Tanner’s day, and if the species survived, conditions may actually be more favorable than they were in the 1930s and ’40s. It’s also worth pointing out that the southeastern United States is one of the few places in the world where forest cover has increased substantially in the 21st century.

It should be clear to readers of this series that the Ivory-billed Woodpecker inhabited a larger range and was able to exist in more varied habitats than most publications on the species suggest. This has implications for searchers and for what is deemed to be suitable habitat. For example, the trail cam images from the old Project Coyote search area were obtained near the edge of a bean field, and the putative ivorybill roost holes were in willows (more on that in my next post). Since ivorybills in the western part of their range seem to have lived in willow and cottonwood dominated riparian corridors, fast growing, short-lived willows might have played an important role in the species’ survival in other areas too, although willow-dominated habitat would be dismissed as unsuitable under conventional standards of habitat appropriateness.

It seems to me that even a slightly higher degree of adaptability would increase both the chances of survival and the likelihood that surviving populations might be overlooked due to preconceptions about habitat “suitability” ; this was doubtless one of the factors that led officials to dismiss the landowner in our old search area. Now that beavers are again abundant in the southeast, habitat that might otherwise have been deemed “unsuitable” may now be able to support ivorybills, even if the forest itself is not very old. While I don’t envision a recovery along the lines of what’s happened to the Pileated since my youth (when seeing my first one was a thrill as much for its scarcity as its beauty), I think it’s possible that ivorybill numbers have been increasing gradually and modestly over the past few decades. There was, of course, fairly intensive searching from around 2000-2010 (though it’s mostly over now), but it may be that the more numerous sightings from this period and afterwards are due to more than just the increased effort.

*The remains found in Native American middens were unlikely to have been trade goods; ivorybill parts seem to have been a valuable commodity for ceremonial use west of the Mississippi but not east of it, and in several cases, the remains found were tarsometatarsi, which would be consistent with use as food:

There is strong physical evidence of  ritual value for woodpecker scalps and bills from the upper Midwest and Plains . . .  Remains of the Ivory-billed Woodpecker can be found in sacred bundles, on pipe stems, on amulets, and with burials among the Native Americans of the region. The evidence comes from the western Great Lakes and the Plains; no
evidence of a particular use of Ivory-billed Woodpeckers has yet been un-
covered from the eastern area of the Great Lakes (Ohio, Indiana, and Michigan).

(Leese, 2006.) Leese also points out (in several of his publications) that there’s no evidence that ivorybill parts other than scalps and bills had any trade value.

A number of these midden records were accepted by Tanner in his unpublished 1989 update.


Bits and Pieces Part 5: More on Range and Habitat Variety

I intended this long-delayed installment in the “Bits and Pieces” series to be the year’s final post. I also intended it to the be final installment in the series. While this may end up as the last post for 2017, I’ve decided to cut this short and save some discussion for what I anticipate will REALLY be the final installment.

Follow the links for Parts 1, 2, 3, and 4.

I’ll begin by reiterating that my focus here is not just on records from outside what’s commonly believed to be the historic range but also on records from habitats that depart from the stereotype that has emerged since the 1940s. Those who have studied the ivorybill’s natural history in depth understand that the species was not limited to Singer Tract-like habitats, and Tanner himself made this clear. Nevertheless, there’s a widespread tendency to think about habitat quality with a somewhat romanticized image of the Singer Tract – a vast contiguous area of old growth or virgin forest with huge trees and a high canopy – as the touchstone.

Ivorybill anatomy is specialized and particularly well-adapted to scaling bark, but the specialization pertains to securing food sources not easily retrieved by other woodpeckers (including Pileated) during the breeding season; it is not a specialization tied to particular tree species or habitat types.

Before moving on to a discussion of other records that don’t fit the Singer Tract model, I wanted to address something Cyberthrush said in an October post linking to this series. He wrote:

One of my hopes for the widespread USFWS/Cornell search was that it would at least narrow any possible IBWO persistence down to a very few (perhaps 2-3) localized areas; instead the failed endeavor left open the possibility of 2 dozen or more (sometimes little-birded) areas that scarce IBWOs might conceivably utilize. The lack of a single Ivory-billed Woodpecker appearing on remote, automatic cameras by now at more traditional and well-searched areas remains a pretty devastating obstacle to hope for the species… unless indeed it has found a home in the canopies of less-obvious, lightly human-trafficked woodlands.

I don’t want to hold out too much false(?) hope for this species, but on the other hand I believe most southeast woodland habitat is rarely birded in any regular or significant fashion and the vast majority of individual woodland birds are never systematically recorded — moreover, the ornithological literature is rife with weak, unscientific conclusions/generalizations/assumptions about bird behavior, and perhaps even bird biology. There’s just a lot we don’t know, while pretending we do.

While I don’t share Cyberthrush’s perspective on the lack of remote camera photos (or canopies), he makes very good points about the overall paucity of birding activity in many southeastern forests (I have never encountered other birders in the field) and about the limits of our knowledge.

With regard to his disappointment in the organized search effort, I suspect his hopes were founded in part on similar internalized beliefs; these beliefs were reflected to some extent in the excellent lists of potential habitat compiled by Bob Russell and Bill Pulliam that were so widely referenced a decade or so ago. That’s not to say the listed locations were unworthy of attention (and some of them have yet to receive much); however, there are many other areas that were not included.

In discussing his search efforts in one of these areas, Bill summed it up very well:

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

When found they are usually in regions of original forest growth, rarely being seen where the woods have been once cut over. […] As this Woodpecker seems not to possess the faculty of adapting itself to the new conditions created by civilization, it is quite possible that it will not long survive the passing of our primeval forests. T. Gilbert Pearson, Birds of America, 1936.

Its presence in a region is more often revealed by the large cavities it excavates in dead stumps and trunks than by actual observation of the bird itself. […] This species is common only in the wilder parts of its range. Frank M. Chapman, Handbook of Birds of Eastern North America, 1939.

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

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

We now know that even within the Singer Tract, ivorybills nested successfully at Mack’s Bayou, an area that was predominantly second growth, and I’d suggest that ivorybills showed more than “a bit more flexibility”, when one looks at the historical record.

As Fangsheath at ibwo.net has pointed out both on the forum and in an email, most of the ivorybill localities referenced by Tanner are from within 20 miles of the coast, and “[t]hese coastal forests are quite different from the Singer Tract.” In many of these coastal areas, tree size would have been smaller, the understory would have been thicker, and the canopy would have been lower due to hurricanes and other factors. In addition, the coastal records may have implications for survival in fragmented habitat types.

There are a number of records from Florida and South Carolina involving offshore islands. While most if not all of these offshore islands would have been covered in old growth forest at the time of collection, reaching them would have required crossing expanses of open water or marsh.

In South Carolina, there were multiple reports from barrier islands into the 1880s. A specimen collected in 1879 or 1880 is now lost. Hoxie, writing in 1918, reported that ivorybills were generally “unpersecuated or harmed by man” and that they had opportunistically fed on the barrier islands, following hurricanes, but disappeared when the food supply was exhausted.

My knowledge about Florida and conditions there is limited, but it seems clear that ivorybills lived and bred in a variety of habitats. Florida is also the largest single source of specimens and probably had the largest ivorybill population in the country. What may also be relevant is their apparent use of of mangrove forests, including potentially some 1-2 miles away from the mainland, especially in the Everglades region. As with barrier islands, use of this habitat may have involved crossing some open water between mainland forests (e.g., Big Cypress, associated forested sloughs, and open pine woods, leading to the Gulf of Mexico) and mangrove forests, both along the coastline and in the area referred to as the Ten Thousand Islands, extending south to where Tanner relayed reports during the 1930s from Shark and Lostman’s Rivers within what is now Everglades National Park.

To end this tour of ‘unexpected’ habitats and ‘extralimital’ records, let’s jump north and west by a thousand miles or so and consider records from Arkansas/Missouri and Virginia.

The Arkansas/Missouri records are from George Featherstonhaugh who explored the area in the 1830s and published his account in 1844 as Excursion Through the Slave States from Washington on the Potomac to the Frontier of Mexico; with Sketches of Popular Manners and Geological Notices. Featherstonhaugh reported seeing ivorybills in two different locations – one from a bottomland area above the confluence of the Ouachita and Caddo Rivers, in the vicinity of present day Arkadelphia, AR. This passage is from Volume 2.

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The second location appears in Volume 1 and is more interesting for the purposes of this discussion, since it involves fire damaged upland forest, likely oak-dominated, with hickory and perhaps some shortleaf pine. It’s not clear whether the site is in present day Arkansas or present day Missouri. Either way, it appears to be on the edge of the Ozark Plateau where it meets the Mississippi Alluvial Plain. As an aside, Featherstonhaugh seems to have had an eye for detail and a dry sense of humor:

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Whether the birds were resident in this area or were merely feeding opportunistically in the fire damaged table-land, the habitat involved bears no resemblance to the Spanish Moss festooned, swamp forest stereotype.

Thomas Jefferson included the ivorybill on his list of Virginia birds found in Notes on the State of Virginia (1785). While some authors have suggested that Jefferson was merely following Catesby, it has also been argued that Jefferson’s list was “a product of his personal observations”. If this is true, Jefferson’s observation would not have been from the Great Dismal Swamp (where Pearson thought ivorybills might be present in the early 20th-century), since Jefferson never went south of Norfolk.

Thomas Nuttall, writing in the 1830s, described the ivorybill as being “seldom seen to the north of Virginia and rarely in that state.” In The History of Ornithology in Virginia (2003), Johnston dismisses Nuttall’s assertion but also points to a much earlier and unambiguous record from an upland site, one that seems to have been otherwise overlooked.

The record is from a Native American midden dating to the early Woodland period, ca. 300 CE (AD). The site, Daugherty’s Cave, was used for millennia. It’s in the western part of the state, far from the coastal plain, at an elevation of approximately 2000′. The context suggests that the remains were not trade goods, and Johnston deems it to be “the only known record of this bird from Virginia”.

I’m struck by the fact that if the ivorybill had gone extinct before 1700, and we only had the scant archaeological record to go on, we’d imagine it to be a bird associated with upland forests. On a more serious note and perhaps one more relevant to the discussion that will follow in the next post, I wonder whether the appearance of ivorybill remains in Appalachian middens around 1800 years ago is related to the spread of maize agriculture and tree kills associated with this new farming technology.

So what inferences can be drawn from all this information and what are the implications? I have some thoughts, not all of them had occurred to me before I began  this exploration, and I hope they’ll inspire readers to reflect and come up with their own new insights.

The first and perhaps most mundane observation is that the range maps with which we’re all so familiar, like the one below from the IUCN, reflect the ivorybill’s status after what was likely a long period of decline, especially east of the Mississippi. Unfortunately, these maps reinforce ideas about habitat requirements and tree species associations that are, at best, oversimplifications.

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For contrast, I’ve updated the map I created showing most of the records discussed in this series.

This is not to suggest that reports from outside this “historic” range should be taken seriously today. The map is a fairly accurate reflection of the reality post-Civil War. The more important questions are why the range started to shrink, probably during the 18th-century, and what this more complex analysis of potential habitat types might imply for the species’ survival. That will be the subject of the next and final installment.


Bits ‘n’ Pieces Part 1 – Louisiana Conservationist

I’ve been reviewing copies of Louisiana Conservationist (formerly Louisiana Conservation Review), the official publication of the Louisiana Department of Wildlife and Fisheries (formerly the Department of Conservation). Copies of the magazine, which is in the public domain, can be found in the Louisiana Digital Library. In the course of my research, I found one real gem and a couple of interesting pieces of less significance.

The gem is the initial report on the 1932 Singer Tract rediscovery and T. Gilbert Pearson’s visit to the area. Pearson was the first professional ornithologist to observe the Singer Tract birds. I’ve written previously about Pearson’s visit and have referenced newspaper accounts of his observations. At the time, I was focused on feeding sign and the statement about feeding on rotting stumps. As a result, I overlooked the important fact that Pearson had been searching for ivorybills to no avail since 1891; this highlights the difficulty in finding ivorybills, even during the era of relentless collecting.

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The Ivory-Billed Woodpecker: Rare Bird Considered Extinct – Found in Louisiana, Margaret A. Coogan, July 1932, Louisiana Conservation Review

The newspaper articles were somewhat less detailed than Coogan’s account, which includes some interesting tidbits. It seems likely that Pearson himself provided the information to Coogan, either directly or via Armand Daspit. There’s an inaccuracy; the mention of carpenter ants as prey is not supported by the literature.* The only record of nesting in pines is in Thompson (1885), a record that Tanner deemed “questionable”.

Edited to add: Hasbrouck (1891) included a second-hand claim of a nest in pine from northwest Alabama. Tanner accepted the report but possibly not the claim of a nest, as the latter is not mentioned in the monograph.

Somewhat more interesting is the observation, “Occasionally it feeds on the ground like a Flicker”.  In 1937, Allen and Kellogg would publish a paper describing their 1924 observation of a female ivorybill foraging on the ground and “hopping like a Flicker”. It’s possible that Pearson was aware of this observation, and the reference to scaling the bark of dead pines suggests this is so. (There were no pines in the Singer Tract.) At the same time it’s also possible that Pearson observed the Singer Tract birds foraging on the ground or described foraging behavior based on general knowledge of how ivorybills in Florida, where he grew up, typically fed.

The other interesting tidbits from Louisiana Conservationist pertain to possible ivorybill sightings in the 1950s. Both items (letters from readers and responses from state officials) are certainly questionable, but they also point to the way Pileated Woodpecker became the default, even when the description was inconsistent with PIWO.

The first is interesting for its location. Urania, Louisiana is southwest of the Singer Tract and is relatively close to the Project Coyote search areas. It was founded by Harry Hardtner in the 1890s and is considered the birthplace of conservation and reforestation in Louisiana. The image that prompted the letter is included for reference.

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The second letter is peculiar, but the description is considerably more suggestive of ivorybill than Pileated – like a Red-headed Woodpecker but the size of a chicken.

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There’s one additional tidbit that doesn’t pertain to Louisiana. In the past, I’ve wondered about record committee submissions and how many there may have been over the years. A divided Arkansas committee accepted the Big Woods report (a fact that’s often glossed over in the literature), while the Florida committee rejected the Auburn reports. Other than these submissions, I was aware of one from Texas, from out of range and in unlikely habitat. I recently ran across another, from Florida, also rejected but interesting nonetheless. Here it is, for what it’s worth:

Ivory-billed woodpecker, Campephilus principalis.
FOSRC 2011-852. This bird was described from an observation in suburban St. Augustine, St. Johns Co., on 13 April 2011. Although the observation included key characters of the Ivory-billed Woodpecker, such as a white bill and white pattern on the back while perched, the observation was at a distance of 30 m and made without binoculars. It is the Committee’s opinion that the only acceptable submissions of this species would be those with verifiable evidence (e.g, identifiable photographs or video). The recent controversy over video recordings, audio recordings, and sightings in Arkansas (Sibley et al. 2006) and Florida (FOSRC #06-610, Kratter 2008) calls into question whether the species may have persisted into the twenty-first century.

More soon.

*Ants are described as a prey species in Bendire (1895), but this is based on a misreading of Thompson (1885). Allen and Kellogg (1937) mention an observation involving suspected feeding on ants but found no ants or termites when they examined the substrate. The closest thing to evidence for ants as prey involves a Cuban Ivory-billed Woodpecker with a hugely overgrown bill that was observed feeding on arboreal termites – a species not native to the continental United States. It was observed and collected by Gundlach in 1843 and was also being fed grubs by its companions. Jackson speculates that this might have been a young adult bird, but given the extent of the hypertrophy, this strikes me as being somewhat unlikely. I’ll opt for the altruistic possibility that Jackson also posits. (Jackson 2004).


Go Read Bill Pulliam’s Blog While You Can

I had been planning to do a post with various ivorybill related tidbits in anticipation of the search season, which begins next month. That will be coming in a week or so, but I want to say a little more about Bill Pulliam first (beyond his Luneau video analyses, which I think should be dispositive). This decision was inspired in part by one of our advisors who pointed similarities between what Bill observed in Tennessee and what we’re seeing in Louisiana. While the physical characteristics of our old search area seem to have more in common with Moss Island, Tennessee than where we’re currently focused, Bill’s perspectives are relevant to both.

Edited to add: Moss Island is a small wildlife management area encompassing 3400 acres. I’m not sure what percentage is mature bottomland hardwood forest, but there are a variety of other habitat types. Compared to our search areas it is relatively isolated and distant from other large tracts of forest.

As an aside, Cyberthrush also has a post honoring Bill with a link to an eBird tribute.

With comments included, Bill’s series of posts on Moss Island runs to nearly 54,000 words. There’s no telling how long this series will remain readily accessible online, and indeed some of the images and sound files are no longer available. The entire series is worth reading and saving if you’re seriously interested in the ivorybill. It starts here.

On re-reading the posts for the first time in eight years, I’m struck by how much Bill influenced me without my recognizing it and/or how much the evolution of my understanding between  2009 and today is congruent with the ideas he expressed just as I was getting more deeply involved in searching.

Like Bill, I suspect that the near extirpation and revival of the beaver may be central to the ivorybill’s decline and survival (more about this in my next post). Like Bill, I think that Tanner’s model failed to account for environmental changes that had taken place in the preceding centuries. Like Bill, I think that if the ivorybill survived, it had to have adapted in ways that are inconsistent with Tanner’s a priori assumption that the species is old-growth dependent.

Bill was tough-minded and opinionated. There were times when I thought he considered me a somewhat annoying amateur. While we hadn’t communicated about it in recent years, he took a dim view of my efforts to make sense of feeding sign in the early days. Most of our correspondence took place in the 2000s, while he was still actively blogging about the ivorybill. After that, I sought his input sparingly.

My last exchange of emails with him pertained to the March recordings. Without quoting him directly, I think it’s fair to say he thought the calls were likely or more than likely Ivory-billed Woodpecker. He also thought it unlikely that birds were resident in our search area, based on the pattern of potential encounters, the paucity of strong sightings, and lack of conclusive evidence. I’m not sure I agree; I wish there had been a chance to explore this topic in more depth and that he’d been able to see our search area for himself. Nonetheless, his perspective has led me to consider that other nearby forested areas deserve more attention than we’ve given them to date.

I’ll conclude with three paragraphs from his final post in the Moss Island series. It’s as true today as it was in November 2009 (though I suspect nesting may take place in fragmented second growth, as in our old search area). I hope it inspires you to read the rest. More from me soon.

How does this relate to Moss Island? By Cornell standards, our habitat is unsuitable. Hence, our encounters are largely dismissed out of hand. By doing so, the Cornell approach has painted themselves into a rather nasty corner. The logic is simple. To all appearances, we have Campephilus-like double knocks that are at least as good as what has been heard in the “core habitat” such as Big Woods and Congaree. If one claims that in “core habitat” these represent evidence for the possible presence of Ivorybills, but in “marginal” or “unsuitable” habitat they provide no evidence for the possible presence of Ivorybills, one has committed a logical no-no of the first magnitude. If the same sounds come from places where you have concluded that Ivorybills are not going to be, then you should conclude that these sounds have no relevance to Ivorybills anywhere. Conversely, if you feel these sounds are evidence of the possible presence of Ivorybills in South Carolina or Arkansas, then you must also accept that they would be evidence of the same in Tennessee, Illinois, Mississippi, Florida, Louisiana, and Texas. You can’t have it both ways.

Anyone who seriously considers that Ivorybills might still persist, and that double knocks and other soft evidence have a relevance to indicating their possible presence, should accept that the evidence in total suggests their habitat requirements might be broader than has been assumed by Cornell et al. I’m not suggesting they will nest in fragmented second growth, or even use it as a full-time habitat; but there are ample indications that if these sort of encounters mean anything anywhere then the birds indeed are using fragmented “marginal” habitats for at least parts of their life history. These habitats are hugely more extensive than the “core” habitats, hence this possibility raises all sorts of further hypothetical possibilities for the natural history, survival, and conservation of the species, all of them positive. In the alternative philosophy to Cornell’s, you search where you have learned of rumors, whispers, or credible declarations that something of interest might have been seen or heard there. This of course requires a lot of judgement, and eventually everyone will draw the line somewhere; I’d not put much stock in reports from western Kansas, for example — although good double knocks in Nebraska or Vermont would settle a lot about what they might mean in Arkansas! But until and unless we actually find some reproducible birds and determine what their 21st Century habitat use patterns really are, minds should be kept open.

You will not get anyone involved in the Tennessee project to state that we have established the presence of an Ivory-billed Woodpecker anywhere in Tennessee as a statistical or scientific certainty. None of us has put an Ivorybill on his or her life list. However, if you asked us off the record for our own personal unscientific feelings, I think you would hear several confessions that indeed, some of us do strongly suspect that there has been at least one of these critters tormenting and taunting us in the delta woods for the last several years. Which means we also think that all that follows from this about habitat, behavior, distribution, etc. should be given serious consideration. Interconnected mosaics of fragmented second growth bottomland forest should be included within the spectrum of possible habitats for the species. You will not get anyone involved in the Tennessee project to state that we have established the presence of an Ivory-billed Woodpecker anywhere in Tennessee as a statistical or scientific certainty. None of us has put an Ivorybill on his or her life list. However, if you asked us off the record for our own personal unscientific feelings, I think you would hear several confessions that indeed, some of us do strongly suspect that there has been at least one of these critters tormenting and taunting us in the delta woods for the last several years. Which means we also think that all that follows from this about habitat, behavior, distribution, etc. should be given serious consideration. Interconnected mosaics of fragmented second growth bottomland forest should be included within the spectrum of possible habitats for the species. 

 

 

 


Repost with Addendum: Ivory-billed Woodpecker Sightings and Evidence 1944-2003: The Partially Hidden History

I’m reposting an entry from February 2015 with some new commentary as prologue.

I recently received a Google alert about a new paper on statistical approaches to extinction relying on sight records. According to the paper, which has not yet been peer reviewed:

We have shown that the rate of sightings is the strongest indicator to infer extinction, and too much information about the quality of the sighting can actually be detrimental. Ideally a sighting record would be a list of certain and uncertain sightings only.

I’m curious as to how this model might treat the ivorybill, using the sighting data compiled and analyzed by William C. Hunter in the U.S. Fish and Wildlife Service’s Recovery Plan, a document with which many extinction modelers seem to be unfamiliar.

I’m not trained in statistics, and the literature on this subject is often over my head, but I’m familiar with the concept: “garbage in, garbage out”. Unfortunately, when it comes to the ivorybill, information that is repeated in the statistical papers is often inaccurate:

“For example in 2005, based on a brief sighting and a pixelated image, the ivory-billed woodpecker was declared to have been rediscovered (Fitzpatrick et al., 2005), resulting in the mobilisation of resources for management strategies and recovery plans (Gotelli et al., 2012). However, based on the evidence its rediscovery was brought into question (Sibley et al., 2006), and subsequent extensive searches have failed to result in further sightings (Gotelli et al., 2012).” Roberts DL, Jarić I. (2016) Inferring extinction in North American and Hawaiian birds in the presence of sighting uncertainty. PeerJ 4:e2426c 

An example of a species with a high false detectability is the ivory-billed woodpecker. After 2006, when the US Fish and Wildlife Service offered $10,000 for information leading to an ivory-billed woodpecker’s nest, it was ‘observed’ 14 times and audio recorded 300 times. Nonetheless, the reward remained uncollected (Newton 2009). Lee, T. E. (2014), A simple numerical tool to infer whether a species is extinct. Methods Ecol Evol, 5: 791–796.

Neither of these papers applied the models described to the ivorybill, and I’m not commenting on the validity of the models themselves. I’m pointing to how peer-reviewed literature can sometimes function as an echo chamber in which inaccurate information gets repeated as fact.

While it’s true that extensive searches have failed to obtain indisputable proof, the Luneau video, however controversial, cannot be characterized as a “pixelated image”. There were many more sightings in Arkansas and elsewhere, and in Arkansas, numerous kent-like calls and double knocks were heard and recorded over several seasons.

The book by Newton cited in Lee is Hidden Animals: A Field Guide to Batsquatch, Chupacabra, and Other Elusive Creatures, clearly not a serious scientific treatment of the ivorybill and apparently not a very well-researched one. There were in fact 15 Arkansas sightings between 2004 and 2005 and 14 in 2005-2006. The reward, which was for $50,000, applied to Arkansas only and was offered by the Nature Conservancy, not the USFWS, in June 2006. The source of the claim that audio was “recorded 300 times” is not clear, nor is the meaning. Inaccuracies aside, it’s an enormous logical leap to base an assertion about high false detectability on the inability of an unknown number of bounty hunters to locate a nest in ~500,000 acres of forest.

It may well be true that the ivorybill is more prone to false detectability than some other species; its iconic status makes this seem likely. It’s also true that there have been a number of organized searches for the ivorybill and that the number of sightings has increased as a result of publicity and search activity, at least during the first decade of this century. Nevertheless, many of the records between 1944 and 2003 listed in the USFWS Recovery Plan were unrelated to publicity or organized searches and were incidental to other activities, including bird surveys. In addition, the Recovery Plan tally included some qualitative analysis of the sightings, and an unspecified number of reports were excluded as probable false detections.

I find it odd that Appendix E of the Ivory-billed Woodpecker Recovery Plan is seldom if ever referenced in the recent literature, including Birdlife International’s species account (which I’m honored to say does reference the post below). It’s an official government report and is the most extensively researched document of its kind. I suspect that many readers will be unfamiliar with it and think it merits quoting at length; I’ve bolded some important passages.  I encourage people to click on the link above and read the rest.

Here, a potential encounter is defined as a report not easily explained as something other than an Ivory-billed Woodpecker on the basis of description of the bird, the type of habitat in which it was encountered, and distribution. After the Arkansas announcement was made, post-1944 reports were compiled prior to the 2005 announcement of an Ivory-billed Woodpecker being sighted in Arkansas. A map was produced of these potential encounters in Service brochures. These potential encounters were based on those discussed by Jackson (2004) or otherwise in Service files as “probably reliable,” defined here as not obviously another species. A review of other published literature and files maintained by some State working groups included other potential encounters that are cited and used in this treatment (both before and after 1950). Excluded from further consideration were reports that likely described other species (especially Pileated, but also Red-headed and sometimes other woodpecker species), as well as those reports outside the historical range of the species (as depicted in Tanner 1942) and in unlikely habitats such as golf courses and backyards. The reports between 1945 and 2005 considered further vary in detail, with some accepted based solely on the credibility and reputation of the observer. Reports since April 2005 (i.e., the Arkansas announcement) are similarly treated, but at least one diagnostic field mark had to be observed (most often the white trailing edges on a flying or perched large woodpecker).

It is important to understand the type and level of documentation accepted for this species’ persistence at the time when most collecting of specimens began to trail off (i.e., after 1900) compared with those reports which were accepted without question previously. While most previous treatments break down reports by State, here it is believed that important insights can be made by comparing reports, type and level of documentation, by decade starting with the 1800 and ending with the present. References for those reports besides those of Tanner himself prior to 1940 are provided in Tanner (1942, with cross-reference to location on his maps, his figures 3-10) and are so noted here.

Results and Discussion

The number of locations with Ivory-billed Woodpecker reports peaked between 1880 and 1910, the same period when most specimens were collected (Figures 1, 2). The number of locations with potential reports after 1940 generally dropped below the number of locations with all reports between 1900 and 1940. However, when including only potential encounters between 1900 and 1939, the range in number of locations among decades was roughly similar to the number of locations with potential encounters in the decades between 1940 and 2009, only dropping below 10 locations during the 1990s. The number of locations within each decade with multiple reports among years never exceeded 10 per decade prior to the extensive efforts underway after 2005 to search for this species.

Prior to 1940, only a small percentage of locations from decade to decade provided the source of reports from multiple years within any one decade, ranging from 12 to 28 percent of all locations with birds reported within each decade (Figures 3, 4). After 1940, there was a slight increase in the percentage of locations with multi-year reports in the later decades, ranging from 9 to 51 percent of all locations with birds reported within each decade. Despite this increase in locations with reports from multiple years there was no definitive documentation of persistence at any of these locations. Similarly, a very low percentage of locations with reports spanning more than one decade is documented in the historical record, but again with a slight increase during the latter decades (Figures 5, 6). Reports continue to come from most of Tanner’s regions into the present day with an obvious shift from those regions that included Florida to regions elsewhere (Figure 7).

In summary, there is no evidence that the Ivory-billed Woodpecker was ever widely or consistently relocated in the same areas from year to year or from decade to decade prior to 1940, despite the impression one may have about birds at the Singer Tract during the 1930s. Actually, during Tanner’s study the chore in locating birds often took days or weeks even where pairs or family groups were known to occur from previous years (and actually only one nesting pair at John’s Bayou was consistently relocated during his entire study). Whether the birds were truly more nomadic than previously thought, or whether the low percentage of repeated locations historically has been due to the search patterns of ornithologists and collectors is unclear. What is clear is that the present pattern of reports that do not effectively document occurrence of the species has been repeated from decade to decade for more than a century and that the number of locations with potential encounters within the same decade has varied little since the 1870s.

Whether or not many or all post-1944 reports pertain to actual Ivory-billed Woodpeckers will continue to be debated in some circles, and it also is possible that some of the reports dismissed for purposes of this treatment perhaps should not have been discounted so lightly. However, the pattern of credible-sounding reports accepted for this treatment from locations without firm documentation was from decade to decade slightly lower between 1940 and 2009 than the pattern recorded between 1890 and 1939. Most interestingly, the exceptional increase in locations with potential encounters during the present decade is on the surface similar to what was recorded during the 1930s, given both of these decades experienced a notable increase in amount of effort to firmly document the persistence of this species (with similar results despite substantially fewer observers involved in the 1930s than in the present decade).

RecoveryPlanE1&2RecoveryPlan3-4RecoveryE5-6RecovE7

One caveat about this material: the specific information in Appendix E is potentially subject to change in the future, but the overall patterns are likely to stay similar or the same.

Here’s the February 2015 entry.

This post is inspired in large part by an exchange of emails with Chris Sharpe, an ornithologist who is working on an IBWO literature review. Our correspondence revolved around the IUCN’s species account, which describes the ivorybill as “possibly extinct” and cites recent statistical analyses that suggest extinction is likely, as well as one that indicates survival is possible and another that concludes “very large search efforts are needed to detect small populations.”

Chris pointed out that there are many other species on the Red List that fall into a similar category with many unverified reports but in more remote habitats and nowhere near the search effort that has been expended on the ivorybill. While there’s some validity to this assertion, I think the reality is considerably more complex and that the ivorybill is in fact sui generis.

Many of the specifics of ivorybill history are little-known, and the statistical studies seem badly flawed. One focuses on collection rates but may not adequately address changing attitudes toward conservation in the early 20th century among other factors. Another is perhaps even more problematic for a number of reasons – most importantly its focus on “verified sightings”, which is a particularly complicated issue when it comes to the ivorybill. It omits numerous controversial sightings and does not include post-Singer Tract instances in which physical evidence was obtained, although the authenticity of that evidence has been contested. “Sidewinder” posted the abstract and a good summary of the findings on ibwo.net a few years ago:

Roberts, D. L., C. S. Elphick, and J. M. Reed. 2010. Identifying anomalous reports of putatively extinct species and why it matters. Conservation Biology 24:189–196.

As species become very rare and approach extinction, purported sightings can stir controversy, especially when scarce management resources are at stake. We used quantitative methods to identify reports that do not fit prior sighting patterns. We also examined the effects of including records that meet different evidentiary standards on quantitative extinction assessments for four charismatic bird species that might be extinct: Eskimo Curlew (Numenius borealis), Ivory-billed Woodpecker (Campephilus principalis), Nukupu`u (Hemignathus lucidus), and O`ahu `Alauahio (Paroreomyza maculata). For all four species the probability of there being a valid sighting today, given the past pattern of verified sightings, was estimated to be very low. The estimates of extinction dates and the chance of new sightings, however, differed considerably depending on the criteria used for data inclusion. When a historical sighting record lacked long periods without sightings, the likelihood of new sightings declined quickly with time since the last confirmed sighting. For species with this type of historical record, therefore, new reports should meet an especially high burden of proof to be acceptable. Such quantitative models could be incorporated into the International Union for Conservation of Nature’s Red List criteria to set evidentiary standards required for unconfirmed sightings of “possibly extinct” species and to standardize extinction assessments across species.

Here are the Ivory-billed Woodpecker sighting data they used:

Physical evidence: 1897, 1898, 1899, 1900, 1901, 1902, 1904, 1905, 1906, 1907, 1908, 1909, 1910, 1913, 1914, 1917, 1924, 1925, 1932, 1935, 1938, 1939

Independent expert opinion added: 1911, 1916, 1920, 1921, 1923, 1926, 1929, 1930, 1931, 1933, 1934, 1936, 1937, 1941, 1942, 1943, 1944

Controversial sightings: 1946, 1948, 1949, 1950, 1951, 1952, 1955, 1958, 1959, 1962, 1966, 1967, 1968, 1969, 1971, 1972, 1973, 1974, 1976, 1981, 1982, 1985, 1986, 1987, 1988, 1999, 2004, 2005, 2006

Data were from Tanner (1942), Hahn (1963), Jackson (2002, 2004), Fitzpatrick et al. (2005), Hill (2006), and Floyd (2007).

Some conclusions: For the Ivory-billed Woodpecker, the prior sighting record suggests that even by the time of the first controversial sighting, the species was relatively unlikely to remain extant (ca. 21% chance), regardless of the level of evidence (physical or independent expert opinion) used…the effect on the predicted extinction date will depend on the details of the sighting record. Including controversial sightings will, by definition, move expected extinction dates forward in time. An ever-increasing burden of proof should be required with increasing time since the last verified sighting. The burden of proof also should be greater when there is a pattern of frequent sightings prior to the last accepted record and lower when long periods between sightings are common in the historical record.

A second paper published in 2012 reached the same conclusion using 39 sightings “classified as certain and 29 classified as uncertain”.

The insistence on verification is problematic because it’s founded on an appeal to authority, and for much of the time frame in question, the primary if not sole authority was James T. Tanner. Tanner had a strong predisposition to dismiss every post-Singer tract report he received and was somewhat cavalier about reports he investigated in the late ’30s as well. (In fairness, Tanner did accept a number of post-Singer Tract sightings in an unpublished, late 1980s update to the records section of monograph.)

Tanner likely underestimated the population IBWO population in the late 1930s. At minimum, he missed six pairs in Mississippi, according to Jackson ( In Search of the Ivory-billed Woodpecker, pp. 60-62.  These details reinforce the point made by “Fangsheath” of ibwo.net that, for the ivorybill at least, demanding verification leads to “a rather vicious circularity”. In a recent email, Fangsheath also pointed out that “the Roberts et al. scheme fits tidily into the narrative created by Tanner, that the Singer Tract was the last hope of the ivory-bill, and that when that: wilderness was lost the bird essentially became extinct . . . Tanner searched across several states for the bird and found none elsewhere, yet he himself believed that the bird survived in a number of areas. And so we have a curious contradiction – on the one hand an appeal to authority is being used to exclude many sightings, and on the other hand that same authority is saying the bird exists in areas where sightings are excluded. The mythos that the bird had very specific habitat requirements clouded every search effort and every sighting evaluation, before and after 1944.”

Fangsheath’s observation about the impact of Tanner’s narrative on future search efforts is profoundly important. Tanner’s ideas about habitat, which were in large part a product of his cultural background and the “myth of the frontier”, hardened over time. In later years, he ignored some of the caveats he set forth in his own monograph. But even his approach to reports from the 1930s reflected a set of beliefs about habitat requirements that had no scientific basis. Many people, myself included, are prone to reflexively accepting these assumptions about “habitat quality” because the conventional wisdom is so deeply engrained.

Fangsheath also reminded me that in the years before Tanner, the species was being written off and had been for decades. Florida was believed to be the last stronghold; the Singer Tract and Atchafalaya basin were not considered, nor were the large tracts of overcup oak/water hickory forest (where Beyer found ivorybills in 1898), many of which were untouched until the 1940s. Unlike the Singer Tract, these areas were often roadless and very difficult to penetrate; the Tract was bisected by a road, had few deep bayous, and was largely free of undergrowth, making it much easier to search. I’ve already discussed Tanner’s difficulty in finding ivorybills anywhere besides John’s Bayou. In this context, it’s worth noting that Bick’s 1941 sighting (from his car on Sharkey Road) involved two birds feeding in a lower lying “ash flat” in which overcup oak predominated.

In addition to these conceptual flaws, the papers grossly underestimate the number of post-Singer Tract encounters within the historic range. While it is impossible to quantify the controversial reports, it’s clear that the 26 or 29 referenced in the studies are the tip of the iceberg. There are well over four times that many on record for the 1944-2003 time period. And no doubt, numerous encounters never made it into the literature.

I initially posted a brief comment about this on Facebook and ibwo.net, with a link to Jerome Jackson’s 2002 Birdwatching Daily article listing 20 pre-Arkansas and post-Singer Tract encounters (some just auditory and one from Cuba) and a reference to Michael Steinberg’s Stalking the Ghost Bird catalogue of 85 sightings during the same time frame. A commenter wrote, “Yes but no confirming photos”. That also led me to think it would be worthwhile to explore this subject in a somewhat more depth, since there is physical evidence, albeit contested, related to several post-Singer Tract and pre-Arkansas reports.

Before turning to the physical evidence, it’s worth reiterating that the 1944 date for the last “verified sighting” is fundamentally flawed and arbitrary. The 1944 date is for the “Say Goodnight” encounter that involved artist Don Eckelberry and two local boys, Billy and Bobby Fought, and the purported last lone female IBWO in the Singer Tract. This poignant story was retold in The Race to Save the Lord God Bird, and it has become central to the popular lore about the species. There’s no doubt that the encounter took place, and Eckelberry no doubt believed that the bird was the last of her kind. Roger Tory Peterson apparently received and accepted a report that a single bird, presumably the same one, was still present in 1946. Tanner was likely aware of this and had an additional reason to think that birds persisted in the Tract well after 1944. His papers include a letter stating that Singer Tract game warden Gus Willett saw a pair in November 1948 at North Lake #1 (I have been unable to identify this lake). According to the letter, the “[b]irds are moving over a much larger area than formerly.” The letter mentions that there had been several other sightings during this time period. There’s no reply from Tanner in the archives and no further correspondence about the Singer  Tract birds. It appears that this is the letter from Tanner’s former student, Arthur MacMurray, that is referenced in Jackson, but Jackson’s account does not mention Willett, who would have been familiar with ivorybills. The strong possibility that a pair of birds remained in the Tract for more than four years after it was cut should itself raise questions about Tanner’s narrative.

Jackson’s list of 19 US reports between 1944 and 2003 was undoubtedly not intended to be comprehensive (and his book includes many others). Instead, it focuses on sightings by professional ornithologists and/or people who were familiar with the species. These include: Allan Cruickshank, John Terres, Herbert Stoddard, John Dennis, Davis Crompton (Dennis and Crompton studied ivorybills in Cuba), Whitney Eastman, and William Rhein. Jackson doesn’t mention it, and was perhaps unaware when he wrote the article, but Rhein had filmed the Imperial Woodpecker in Mexico several years prior to his 1959 Florida ivorybill sighting. It strains credulity to think that every one of these experienced observers, most or all of whom were familiar with the species and all of whom knew pileateds well, would be mistaken. Jackson points out that Terres kept his sighting to himself for more than 30 years out of “fear of being scorned.” Such was the climate surrounding ivorybill claims, even in 1955.

Steinberg lists 85 sightings between 1944 and 2003. His list includes most, if not all, of Jackson’s reports, breaking them down into individual incidents. Jackson treated repeat encounters in the aggregate. Nonetheless, most of Steinberg’s reports do not appear on Jackson’s list. Many of them are from less illustrious sources and quite a few are anonymous, but some of them are from game wardens, field biologists, and graduate students in ornithology.

The Ivory-billed Woodpecker Recovery Plan, prepared by the U.S. Fish and Wildlife Service and completed in 2010, includes an even more detailed compilation of records, some of which are of course also included in Jackson and Steinberg. It lists approximately 100 reports of varying quality between 1944 and 2003. Some of these are aggregates, involving multiple observations. The number of observations is sometimes enumerated and sometimes characterized as “numerous”, “multiple”, or “several”, so it’s impossible to arrive at an accurate tally, but the total almost certainly exceeds 150.

Although the Steinberg and the Recovery Plan compilations are more extensive, they are undoubtedly far from comprehensive. For starters, the climate of intimidation around reporting ivorybills was strong enough to deter John Terres in 1955, and that climate of intimidation only grew more toxic over time, as the Big Thicket and Fielding Lewis incidents, not to mention the battle over the Arkansas reports, make clear. In addition, there’s good reason to believe that countless reports from local people, hunters, and amateur birders have been discounted, dismissed, or ignored by authorities, at least prior to the “rediscovery”. Steinberg writes of his first visit to the Louisiana Department of Wildlife and Fisheries Baton Rouge office in 2003,“ . . . few people took the book, or more important the larger issue very seriously. The typical response from many in the office, other than Nancy Higginbotham, seemed to be, ‘Don’t you have anything better to do?’” (Higginbotham claimed two sightings, one of male in 1986 and one of a female in 1987, both in the Pearl River area.) We’re personally familiar with several instances in which reports were dismissed or ignored. One involved the landowner in our old search area, who came forward after the Kulivan sighting and was deeply offended by the way he was treated. As far as I’m aware, no one has done a comprehensive review of records committee submittals within the historic range of the ivorybill; I know of one such submittal from Texas in 2002 that came from unsuitable habitat, outside the historic range, but there may well be others that are more robust.

I’d like to turn to three examples of physical evidence obtained in the post-1944 era. Some of this is fairly well known – the Agey and Heinzmann feather and the Fielding Lewis photographs. The other is somewhat more obscure, but no less interesting for being so.

The Agey and Heinzmann observations took place between 1967 and 1969, in Polk County Florida. They obtained two recordings that Tanner dismissed. There was evidently some very poor communication about it that was compounded by an obvious error on Agey and Heinzmann’s part. They mistakenly thought that calls on their first clip were consistent with some ivorybill sounds from the Singer Tract; they clearly are not. The second clip, which is dominated by a Red-shouldered Hawk, recorded March 3 1968, does have some faint kent-like sounds, but the quality is extremely poor. They are most easily heard on the amplified version that begins at 3:14. The RSHA calls were not what interested Agey and Heinzmann, but they failed to make this sufficiently clear.

I believe Tanner wrote the notes that accompany the recording:

“Well, I’m not sure what to say here. As far as I can determine, there are only four original sound clips here. The recordings at 0:04-0:32 and 0:49-0:57 are certainly flicker-like, especially the continuous series at 0:04-0:21 and 0:26-0:32, but I am less certain about the latter part of the first series (0:21-0:23), which appears to have been recopied twice at 0:41-0:48. A similar vocalization is included at 0:49-0:57 (recopied at 0:59-1:06). Given the very different quality of these sounds relative to those in LNS #6784, combined with the close similarity of the calls to those of Colatpes auratus, leads me to doubt that any of these sounds were given by C. principalis. The recordings from 3 March 1968 (2:45-3:07) represent the calls of Buteo lineatus. Quality unchanged (2;3 – the signal is not bad for the first part, but terrible for the rest, most of which seems to represent copies of various recordings)”

Agey and Heinzmann found several feathers near a cavity, and one was identified as the innermost secondary of an Ivory-billed Woodpecker. Oddly, Jackson wrote that “ . . . some shadow of doubt is cast over these records because Agey and Heinzmann also tape-recorded what they said were Ivory-billed Woodpeckers, and personnel at the Cornell Laboratory of Ornithology identified the birds on those tapes as pileated woodpeckers.” Given that one of the recordings does include kent-like calls, this criticism is not entirely warranted, and the misidentification seems irrelevant in light of the physical evidence (and ironically Tanner seems to have failed to correctly identify the calls on the first clip). Jackson also alludes indirectly to rumors that the feathers were taken from a specimen. These have circulated for years but are unsubstantiated. Agey and Heinzmann published their findings:

Agey, H. N., and G. M. Heinzmann. 1971a. The Ivory-billed Woodpecker found in central Florida. Fla. Nat. 44 (3):46–47, 64.

Agey, H. N., and G. M. Heinzmann. 1971b. Ivory-billed Woodpeckers in Florida. Birding 3:43.

To the best of my knowledge neither publication is available online at this time.

The next event, chronologically, started with a series of encounters in east Texas in the late 1960s. John Dennis obtained a recording that Tanner initially dismissed, in part for the patently absurd reason that a Pine Warbler is also heard on the clip, but later described as “a real mystery” when confronted with the sonograms and analysis that were suggestive of ivorybill. That recording is now catalogued as IBWO.

Additional slides, taken in 1970 in east Texas by a man named Neal Wright, were turned over to the Museum of Natural History in Philadelphia which also houses the Fielding Lewis photographs. These were made public after the rediscovery, and since writing this in 2015, I obtained permission to post them on the blog. They show what appears to be a female Ivory-billed Woodpecker in a nest cavity. When I first viewed the Wright photographs, I was quite skeptical, but later, I was struck by the resemblance to this image from the Singer Tract.

Wright was apparently quite a local character, and I remain somewhat suspicious, as he may have had ulterior motives; however, the similarity to one of the unpublished images from the Singer Tract is strong, and in the pre-internet era, it seems unlikely that a Texas woodsman would be familiar with any of the ivorybill images that did not appear in Tanner’s monograph.

The Fielding Lewis photographs, taken in South Louisiana in 1971, are far better known, although Lewis wished to remain anonymous. His identity was not revealed until more than three decades later, and he was identified at the time only as “the Chief” (Jackson was unaware of his identity in 2004, though it was made public soon thereafter.) George Lowery presented these images at the American Ornithologists’ Union annual meeting and was attacked by many of his colleagues who deemed them to be a hoax. It’s worth pointing out that there have been hoaxes in recent years (these were swiftly and easily debunked), so there’s legitimate reason for skepticism about any claim. In the case of the ivorybill, however, skepticism has frequently been replaced by a virtually irrebuttable presumption of fraud (or error).

In a letter to Tanner, Lowery (who, unlike most of his detractors, had actual field knowledge of ivorybills) wrote: “I know the man in question very well and I am sure he would not pull something like that. In the first place, where would he have gotten the mounted specimen? Why would he have two photographs of the birds way up on two separate trees? Both of considerable diameter and not subject to being shinnied. Also, assuming he might have had a mounted bird to photograph, why didn’t he get a better picture while he was at it?”

The most common reasons given for believing that Lewis hoaxed the photos are that the bird is similarly positioned in both images (similarly but not identically, a neat trick with a specimen) and that the bill and feet are not visible. Bear in mind that these pictures were taken with a Brownie or Instamatic camera, and the quality is very poor. Nonetheless, I believe a foot is very faintly visible in both photos, positioned in a manner that would be expected of a live Campephilus woodpecker. I worked from scans of the originals and made some modest enhancements in Photoshop. Note also that in the first picture, both a cavity and bark scaling can be seen on the tree.

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Regardless of whether my analysis is correct, the foundation for claiming that these photographs were faked is shaky indeed – not only for the reasons Lowery gave but also because of Lewis’s reticence about revealing his identity, insistence on keeping the location secret, and lack of any discernible motive.

The recovery plan mentions two other pieces of physical evidence. One is a feather that was purportedly found in a nest or roost cavity in 1985, and the other is a photograph supposedly taken in Georgia in 1975 (correction, 1965).

It’s not my intention to fault the IUCN or to quarrel with the “possibly extinct” designation, although I think Bill Pulliam’s analysis of the Luneau video in light of Rhein’s Imperial Woodpecker film should be dispositive. My main purpose is to call attention to the fact that there’s considerably more evidence for survival than is popularly recognized or than appears in the scientific literature. There are multiple instances of people, often outstanding birders, hesitating to come forward with reports and hard evidence – for decades. Terres waited 30 years; in the cases involving physical evidence, only Agey and Heinzmann went fully public and identified themselves in making their claims; in Stalking the Ghost Bird, Steinberg includes detailed 2005 field notes written by a Louisiana “birder for more than forty years” who “has also worked as a contract ornithologist conducting bird surveys on rice and crawfish farms for more than ten years.” This individual too requested anonymity. To a significant extent, the shortcomings in the literature are directly related to the controversy that has surrounded this species for nearly a century (remember Mason Spencer who went so far as to obtain a permit and kill an ivorybill to prove the species persisted) and the accompanying climate of unhealthy skepticism that has, if anything, grown even more unhealthy since the rediscovery. This sets the ivorybill apart from other possibly extinct species.

I’ll be heading for Louisiana at the end of the week and will post a trip report when I return.


Insights, Ants, and Old Growth: a Nuanced View of the Ivorybill’s Decline and Possible Survival

I’ve just finished reading Tanner’s dissertation and have gained some new insights into topics that have been discussed in a number of earlier posts.

Conventional wisdom, following Tanner, holds that the Ivory-billed Woodpecker’s decline and possible extinction were caused by habitat loss, specifically the logging of old growth forests during the 19th and early 20th centuries. Birdlife International’s fact sheet on the species suggests “that large contiguous tracts of mature woodland would be required to support a viable population”, referencing Jackson 2002. Snyder et al. have proposed an alternative hypothesis that “human depredation was the primary factor.”  (p.9).

Tanner’s model depends on the idea that food supply was the limiting factor on ivorybill populations, because the species is highly specialized, and that old growth conditions were optimal or essential. While Tanner was aware that ivorybills bred successfully in an area that was predominantly second growth, at Mack’s Bayou, he glossed over this fact in the monograph, and became more dogmatic about old growth as a requirement in later years.

Snyder and some others have contended that the ivorybill is a generalist. According to Snyder, “the data available on diet and foraging methods simply do not provide compelling evidence for strong feeding specialization.” Snyder goes on to suggest that “[i]ts apparent skill in exploiting recently dead timber, coupled with its ability to feed in a variety of other ways, may even have given it some significant foraging advantages over the pileated woodpecker, a species apparently much less capable of bark stripping. Indeed, the pileated woodpecker, like other Dryocopus woodpeckers, may well be more of a food specialist than any of the Campephilus woodpeckers.” (p. 37).

As I see it, there are elements of truth in both models, but neither is complete. In addition, I think that each model relies on at least one flawed premise.

The old growth/virgin forest component of Tanner’s model fails to account for the facts that the Singer Tract population was dwindling even before logging began in earnest and that birds appear to have remained in the Tract until well after it had been extensively logged. Tanner suggested another possibility, “perhaps the greatest factor reducing the rate of ivorybill reproduction is the failure of some birds to nest. One reason for their not breeding is immaturity, for it is probable that ivorybills do not nest until they are two years old. Another possibility is that the quantity of food available to the woodpeckers may determine whether they will nest or not.” (p. 83).

Tanner struggled to account for the fact that the ivorybill population at Singer was dwindling by the mid-1930s, even though overall habitat quality had, if anything, improved relative to what it had been a few decades earlier. He attributed the higher relative abundance in previous years to tree mortality due to fires that took place in 1917 and 1924. Tanner also recognized the probable importance of fire in the pre-contact era, although he seems to have been unaware of the ways pre-contact Native Americans used fire, both for agriculture and habitat management. (The impacts of Native American fire use were almost surely different from what occurred in the 20th century Singer Tract).

Neither Tanner (whose study predates the emergence of the discipline) nor Snyder, take environmental history sufficiently into account. There had been major ‘changes in the land’ long before large scale logging began in the southeast and before the reports of local abundance on which Snyder relies. These changes include: the post-contact collapse of Native American civilizations, the introduction of European plant and animal species, the clearing of log jams on major and secondary North American rivers, habitat fragmentation due to the plantation economy, and the near extirpation of the beaver.

All of these elements likely contributed to a major decline in ivorybill populations. Ivory-billed woodpeckers likely concentrated locally in response to major disturbances, regardless of whether forests were old-growth or advanced second-growth, and this type of specialization caused birds to congregate, making it easier for collectors to kill them in large numbers in short periods of time. Snyder likely misinterpreted this collection of large numbers of Ivory-bills in short periods of time as reflecting a greater regional abundance. In contrast, and more consistent with Tanner, this ecological response to disturbed areas led, in some places, to the collectors extirpating regional populations.

In the latter part of the 19th century, hunting probably sped the collapse of the remaining population, but Snyder’s claim that available data on diet and foraging methods do not provide compelling evidence of specialization fails to account for the anatomical and other evidence that suggests otherwise. It also fails to account for the Pileated Woodpecker’s far more extensive range and ability to thrive in a wider variety of habitats, including badly fragmented and degraded ones. I made some of the case for specialization in a series of recent posts, but there’s more to add, especially with regard to ants.

In one of those posts, I hypothesized that the inability to exploit ants as a food resource was a key component, perhaps the primary component, in explaining the decline of the ivorybill. A commenter asked whether there’s evidence to support the idea that ivorybills and other Campephilus woodpeckers don’t feed on ants and also whether there’s evidence to support the idea that Campephilus woodpeckers don’t regurgitate.

Adult Campephilus woodpeckers rarely feed on ants but do not feed them to their young. They make frequent trips to the nest with food items stored in the bill or at the back of the bill. (M. Lammertink, pers. comm.) Dryocopus woodpeckers and those in closely related genera (the “tribe” Malarpicini) feed their young by regurgitating, while other woodpeckers do not. (Manegold and Topfer, 2012). I think the capacity of Pileated Woodpeckers to consume ants in large quantities and to feed them to their young is a significant distinguishing factor and that Tanner was correct in suggesting that food supply was a major limiting factor on Ivory-billed Woodpecker populations.

Ants comprise up to 33% of the world’s terrestrial animal biomass. In Finland, they comprise as much as 10%. In tropical forests, the percentage is much higher, exceeding vertebrate biomass by 400%. Tanner’s comparative analysis of available ivorybill and pileated food did not include ants, so Tanner’s comparative estimate of available insect prey – suggesting that pileateds in the Singer Tract had access to approximately four times what ivorybills did – was in fact extremely low.

Tanner’s dissertation concludes with a discussion of Audubon’s ivorybill dissection, something that was omitted from the monograph. While I had a passing familiarity with the Audubon material, I had not looked at it carefully. Nor had I compared his ivorybill and pileated dissections.

Tanner wrote: “The proventriculus is both muscular and glandular. Audubon’s drawings and text indicate that the proventriculus of a Pileated is much larger in proportion to the stomach than is the case in the Ivory-bill.” Audubon described the ivorybill proventriculus as being only minimally wider than the esophagus. By contrast, the pileated proventriculus as “an immense sac, resembling a crop, 2 1/4 inches in length and 1 and 5 twelfths in width,” or nearly three times as wide as the esophagus.

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Audubon’s drawing of Ivory-billed Woodpecker digestive tract showing slightly widened proventriculus.

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Audubon’s drawing of Pileated Woodpecker digestive tract showing large, sac-like proventriculus.

The proventriculus and stomach of one of Audubon’s specimens contained “a vast mass of ants and other insects”. According to Bent, Beal found one pileated stomach that contained 2,600 ants. (Others contained fewer, 153 and 469, according to Sutton.) Thus, it’s clear that even if ivorybills sometimes ate ants, they lacked the capacity to consume them in large quantities, let alone feed them to their young.

This supports Tanner’s view that specialization was a limiting factor on ivorybill populations. I’ve previously suggested that this might apply only to breeding season, but it seems reasonable to infer that it’s a factor year-round, based on the differences in proventricular structure.

All of that said, I’d argue that this specialization should not necessarily be read to include dependence on large tracts of mature, contiguous forest. The data from the Singer Tract suggest that even under these ‘optimal’ conditions, breeding was limited. And the fact that the Mack’s Bayou birds bred successfully in an area of second growth suggests that birds could thrive under ‘suboptimal’ conditions. The extent to which survival might be possible in fragmented habitat is less clear, but Snyder (citing Jackson) refers to the Mississippi population of six pairs in a 19.2 square mile forest that Tanner missed; the tract is less than 1/6 the area of the Singer Tract and is smaller than many contemporary wildlife management areas.

The tract, known as Allen Gray Estate, was west of Skene, Mississippi in Bolivar County; some or all of it is now part of Dahomey National Wildlife Refuge; the US Fish and Wildlife Service Habitat Management Plan for the refuge (2013) states that the forested portion of the refuge comprises 8100 acres and provides this historical information, “Dahomey NWR is located on the grounds of the old Dahomey Plantation founded in 1833 by F.G. Ellis and named after the homeland of his slaves. Much of the land west of the refuge was probably cleared for cultivation around this time. The land went through several owners and was purchased by Allen Gray in 1936. The portion that became the refuge was known as the “Allen Gray Woods”. This was the only significant portion of the plantation still forested.”  This 8100 acre figure is 25% lower than the figure reported by Jackson and Snyder.

While I have been unable to find a detailed logging history of Bolivar County, it is in the heart of the Mississippi Delta, which was known for its plantations. Between 1900 and 1940, Bolivar County was more densely populated than Madison Parish: 39.1 people per square mile as opposed to 18.9 in Madison Parish in 1900, 78.92 as opposed to 22.78 in 1930, and 74.57 as opposed to 28.33 in 1940. Based on population density and the number of towns, it seems self-evident that the habitat in Bolivar County was considerably more fragmented than was the Singer Tract.

Thus, there is good reason to question Tanner’s old growth model as well as the idea that large contiguous tracts of mature forest are required. Similarly, there’s good reason to question Snyder’s argument that hunting rather than specialization was the primary cause of the ivorybill’s collapse.

Efforts to reintroduce the beaver in the southeast began in the 1930s, and the population has been growing ever since. Beavers injure trees by partially or fully girdling them and by altering hydrology, which weakens or kills trees at the edges of the ponds they create. Beaver damage renders trees more vulnerable to infestation by ivorybill prey species, something we’ve observed repeatedly in our search area. In Tanner’s day and in the late 19th century, the beaver was barely a part of the southeastern ecosystem, but by the 1950s, beavers again were playing a role in altering southern forests, whether mature or successional.

If the ivorybill was able to survive the logging of the last large tracts of old growth forest, as I think it was, the reintroduction of the beaver may have been central to its persistence. If this hypothesis is valid, there is considerably more potential habitat today than there was in Tanner’s era; much of this potential habitat has been overlooked or dismissed in organized search efforts; and the dismissals of post-Tanner reports based on his habitat model rely, at least in part, on a false premise.

 

 

 


Old Singer Tract Images Compared with Two More Recent Ones (from Elsewhere)

1967 slides taken by Neal Wright of a putative Ivory-billed Woodpecker in Texas are viewable on Vireo (search Ivory-billed Woodpecker), but high resolution scans have not been widely circulated as far as I know. These images were not made public until after the the Arkansas “rediscovery”, more than three decades after they were obtained. Wright’s story is mentioned in Jackson (2004) “Reynard saw the photo and said that it was fuzzy but definitely of a Campephilus woodpecker.” It’s clear from the context that Jackson had not seen the images at the time of writing.

When I first encountered the Wright slides, I was skeptical, but after seeing some lesser-known Singer Tract photographs as well as other images of Campephilus woodpeckers in cavities, my opinion started to shift. After finding additional ivorybill photographs in the Cornell archives and in Tanner’s dissertation, I thought it would be worth posting some of those images along with one of Wright’s slides for the sake of comparison.

Of course, it’s up to readers to draw their own conclusions, but I think a few things are worthy of note. First, the Wright slides were taken long before the internet, at a time when the only readily available image of an ivorybill in a nest cavity was Tanner’s Plate 1, which is quite similar to Fig. 43b (below). The posture of Wright’s bird is much closer to the ones shown in the then virtually unknown and/or unpublished images, especially those from the 1938 nest. The placement of the cavity is also strikingly similar, just below a major fork. It seems highly unlikely that Wright would have been aware of obscure Singer Tract photographs.

While the image quality is too poor to be certain, there appears to be excavation similar to work found on some Singer Tract nest and roost trees to the right of the nest cavity in Wright’s slide. Again, this is a fine detail that would likely have been unknown to Wright and that would have been difficult to fabricate.

These are very poor quality images; the malar stripe seems a little too extensive, although this could easily be a function of angle and lighting. As with the Fielding Lewis photographs, which were taken several years later, I have to wonder why anyone intent on committing a hoax wouldn’t do a better job. And in the case of the Wright pictures, it would make more sense if the template for such a hoax would have been Plate 1 in Tanner, rather than photos that were unknown to all but a handful of people, most of them at a northeastern university.

Finally, I think the fact that the images were turned over to an ornithologist (George Reynard, scroll down for his obituary) but were kept confidential for so long also tends to support the idea that they’re authentic. Neal Wright may have had an agenda – a desire to protect the area where he took the picture – but the images were not used to serve that purpose.

Edited to add: This fascinating article on a recent, non-ivorybill related hoax suggests that it’s not uncommon for hoaxes to be paradoxically uneven in quality, and that hoaxers’ motives can be murky and bizarre. Nonetheless, I think that other factors point to authenticity for both the Wright and Lewis photos.

Ivory-billed Woodpecker w16-1-001 copy

© N. Wright/VIREO USA – Nest with adult protruding, slide mount dated 5/70 (apparently the duplication date). Poorly defined bird is apparently peering out of a cavity in the upper left of the trunk, below the fork.

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Ivorybills at Nest, John’s Bayou 1938, female’s head protruding from cavity

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Ivorybills at Nest, John’s Bayou, 1935, male’s head protruding from cavity

 

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Images from the Singer Tract and James T. Tanner’s Dissertation Courtesy of Courtesy of the Division of Rare and Manuscript Collections, Cornell University Library

 

Another item I found in Tanner’s dissertation merits comparison with one of Project Coyote’s camera trap photos, since the tree species involved are the same. Plate 7 in Tanner shows ivorybill feeding sign on honey locusts, but the reproduction in the monograph is very dark. The figure from the dissertation is much brighter, making it clearer what Tanner was attempting to show. I think the similarity to the work on our target tree, where I had a sighting a week prior to the capture, is striking.

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Courtesy of the Rare and Manuscript Division, Cornell University Libraries

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Trail cam photo with scaled tree in the foreground and suspected female Ivory-billed Woodpecker in red box, Nov. 2009

To enlarge the trail cam photo, click here.


Scaling Data 2012-2016

To expand on some of the data included toward the end of the March trip report (which is worth reading in in conjunction with this post), I thought it would be informative to provide a season by season and sector by sector breakdown of the scaling I and others involved with Project Coyote have found since the spring of 2012. To do so, I’ve gone through my notes and photographs and have done my best to reconstruct the data collected. While not complete (I’m quite sure a good deal more scaling was found in Sector 3 during 2013-2014, for example), I think this breakdown is a fairly accurate reflection of what we’ve found over the years.

As discussed in previous posts, I think extensive scaling on hickory boles is the most compelling for Ivory-billed Woodpecker. Bark on this species is thick, dense, and usually remains very tight for a long time. Extensive scaling on sweet gum boles and oaks (upper boles and large branches) is second among work that I’ve found. Work on small boles, and higher and smaller branches is somewhat less compelling and is more significant for its abundance. Some of the high branch scaling and work on smaller boled sweet gums may well have been done by Pileated Woodpeckers (and possibly by Hairy Woodpeckers), but the abundance, the presence of large bark chips in many cases, the way it appears in clusters, and the fact that Pileateds scale infrequently suggest a different source for much of it.

I have excluded all work where squirrels are suspected but have counted one tree, a hickory found this year, on which the work could well have been that of a Hairy Woodpecker. Hairies do forage for Cerambycid beetles just under the bark, but they’re only capable of removing tight bark in small pieces; their work on hickories is perhaps more accurately described as excavation through the bark.

The trail cam images toward the end of this post are the best we have (out of many thousands of hours of coverage) showing how these species forage on suspected ivorybill feeding trees.

All trees were live or recently dead (twigs and sometimes leaves attached). All scaling was on live or recently dead wood.
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Totals

Sweet Gum (Liquidambar styracifula)

Sector 1:         46

Sector 2:         8

Sector 3:         51

                        105         (84.68%)        

~15% had scaling on boles (a few of these were large trees). The majority of work was on crowns, including larger branches. Fallen trees were included when woodpecker involvement was evident and bark was tight.

Bitternut Hickory (Carya cordiformis)

Sector 1:            3

Sector 2:            4

Sector 3:            7

                           14         (11.29%)

All trees were standing; scaling was on boles and was very extensive (the tree shown on the homepage is one example) with one exception from this year . Insect tunnels were visible in all examples. An additional hickory with a modest amount of high branch scaling was found in Sector 1 this year but was not counted for this analysis.

Oak (Quercus) spp.

Sector 1:         1

Sector 2:         4

Sector 3:         0

                         5         (4.03%)

All oaks had scaling on large branches; one also had some on the bole. All oaks in Sector 2 were found in a single cluster.

We have some information on forest composition in Sector 3, and it appears that sweet gums make up approximately 19%, oaks upwards of 35%, and hickories somewhere under 10%. Sectors 1 and 2 may differ and be more varied in overall composition.

The overwhelming preference for sweet gums relative to their abundance stands out. The scaled oaks are a mix of species, one Nuttall’s, one willow, the others unidentified.

In Sector 3, I am treating the compact stretch from the location of Frank Wiley’s sighting last spring/downed sweet gum top where we had the camera trap to just south of our current deployment as a cluster. The estimate of 23 trees being found in this area is conservative. I have only found one instance of recent scaling north of the location of the downed limb/Frank’s 2015 sighting. The main cluster has been in the same vicinity this year and last, with additional work scattered around farther south. Two of the hickories are within 30 yards of each other, approximately half a mile from the cluster, and one was on the edge of the concentration.

It also may be significant to note that we found a cluster of old but intriguing cavities in the same vicinity as the Sector 3 concentration in 2013-2014. Most of these seem to have fallen. The difficulty we’re having finding active, suggestive cavities is vexing, and may be the most compelling reason to be skeptical about the presence of ivorybills in the area. At the same time, finding Pileated cavities is difficult, even in defended home ranges.

I’m treating Sector 1 as a single concentration; the vast majority of the work is on a natural levee where sweet gums are abundant. The entire area is considerably larger than the other clusters, but given the abundance and ease with which we’ve found sign there over the last five seasons, I think it constitutes one area of concentration.

In Sector 2, there was a small cluster in the area where I recorded putative kent calls in 2013, with work found in 2012 (spring and fall) and 2013. Because the area is small with open sight lines, I can be confident there has been no recent work there since late in 2013 (I last passed through it with Tom Foti back in March of this year.)

The sweet gum work Tom and I found on that day was perhaps half a mile north of this cluster, within 100 yards of the hickory on the homepage. The other hickories found in the 2013 and 2014 seasons were not far away, no more than 500 yards apart as the crow flies.

There’s obviously some bias here, since there’s a relationship between finding feeding sign in a given area and spending time there. Nevertheless, I have little doubt that the putative ivorybill work tends to be clustered. I also have little doubt about the strong preference for sweet gums, since I’m not looking at tree species when I look for scaling. The degree to which sweet gums are favored has only become clear over the last year or so.

Frank pointed out this data does not reflect most of the scaling that likely exists in relatively close proximity to the Sector 3 cluster but cannot be quantified because it is in an area we have intermittently visited due to  inaccessibility. Only two or three examples are from this area, which has been visited a handful of times.