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The Two Faces of James T. Tanner – A Study in Selective Memory and Blindspots

In a 1936 letter to James Tanner before Tanner began his survey of possible ivorybill habitat in the southeast, Herbert Stoddard wrote, “The area where they (Ivory-billed Woodpeckers) may occur at present is simply tremendous, not restricted as many believe.” Stoddard continued, “. . . if I had the rest of my life for the purpose, I doubt I could cover adequately half the ground I now think worth investigating. When I say adequately I have in mind five days I spent looking especially for these birds with men such as Bob Allen and Alex Sprunt on an area of some ten thousand acres known to be frequented by several pairs of these birds without seeing one. Of course this was due to the element of luck, as others have gone in the same area for a few hours and seen one or two. But it indicates the time one would have to spend in these great river valleys to really be reasonably sure that the birds were absent or even extremely rare therein.” Tanner was one person, and he clearly didn’t have the time to devote to the thorough survey Stoddard suggested, but the later record suggests that he failed even more deeply to take Stoddard’s words to heart. Stoddard’s perspective leaves room for the possibility that Tanner grossly underestimated the ivorybill population in his monograph, something that might lead to very different projections about the likelihood of survival today. It also sheds additional light on the difficulties in searching for ivorybills and on what appear to be some significant blindspots in Tanner’s thinking about the species.

I recently wrote a Facebook post in which I stated Tanner had a “hard time” finding Ivory-billed Woodpeckers. A very prominent American birder and ivorybill skeptic promptly shot back asking for citations, which I provided; I wouldn’t play along with the snarky response, but the exchange gave me the impetus to write this post. To most birders, Tanner is a kind of heroic figure, a pioneer ornithologist, and the author of the only in-depth, definitive study of the Ivory-billed Woodpecker, a bird that, in Tanner’s telling (and even more so in the retelling), was a super specialist that depended on virgin forest for its survival. Tanner is also rightly seen as having played a central role in the development of modern environmentalism, fighting to save the Singer Tract itself and later helping to create Congaree National Park, one of the few remaining substantial old growth stands in the south.

Those who are more deeply steeped in ivorybill lore are likely to have a somewhat different perspective, even as they admire Tanner’s good qualities. In later years, Tanner became increasingly dogmatic about ivorybill habitat requirements and was usually harshly dismissive of  reports from others – including John Dennis in Texas and Agey and Heinzmann in Florida. (This dismissiveness began to take hold in the early 1950s.) By no later than 1985, and probably much earlier than that, Tanner had become convinced the ivorybill was extinct, a conviction that he usually leavened with the statement that he’d love to be proven wrong. Ivorybill aficionados may also raise questions about the 1930s surveys he conducted in the southeast, and the rapidity with which he dismissed almost every place he visited as being unsuitable, sometimes based on a visit lasting a day or two. Most of these visits were made outside of breeding season, at times when finding ivorybills was considerably more difficult.

Tanner may have been right to dismiss many of these areas, but the possibility that he might have missed several populations cannot be ruled out, especially in light of the letter from Stoddard, an established ornithologist with first-hand knowledge of the species. At minimum, Stoddard’s letter put Tanner on notice that ivorybills could be very difficult to find.

Were preconceived beliefs driving Tanner from 1937-1939; was he being cavalier in his dismissals; or was he simply doing his best to accomplish what Stoddard said would take a lifetime in a few weeks spread over three years? It was probably all of the above, but whatever the reason, his mindset became an even bigger problem as time went on, leading him to foment the false impression that ivorybills should be easy to find, a notion that informed the views of my interlocutor on Facebook and of many those who believe the species is extinct.

The fact is that when Tanner was in the Singer Tract, the only birds he could find on a regular basis were the “John’s Bayou Family”, the group first studied in 1935. Their nesting and roosting grounds were approximately 1 mile from Sharkey Road. From 1935-1939, the birds nested in the same general vicinity. Three of the four nests were in very close proximity to one another, and the greatest distance between any two nest sites was 3/4 of a mile. Despite this clustering, it took Tanner five days to find a nest in 1939, when he didn’t have J.J. Kuhn (who had been forced out of his job as Singer Tract Warden) to assist him. While Tanner paid respect to and credited Kuhn, the passage of time has made it increasingly clear that he downplayed the degree to which he depended on Kuhn to find ivorybills. Kuhn had been observing the birds for several years before the 1935 expedition (which also took several days to find ivorybills), and it’s reasonable to infer that the John’s Bayou family was already somewhat habituated to human presence by 1935. Certainly after ’35, they were accustomed to human activity in the immediate vicinity of their nest sites. The only other ivorybill Tanner saw was one he named Mack’s Bayou Pete, presumably a bird hatched in 1935 from a nest that Kuhn found. As with the John’s Bayou pair, this bird was found within a home range that had been roughly delineated in 1935; Tanner believed he could recognize Pete’s voice, but the bird was far more frequently heard than seen.

Edited to Add: I’ve been reminded that the 1935 Mack’s Bayou Nest failed, and that Pete more likely fledged in 1937. The fate of the adult Mack’s Bayou pair is unknown.

Tanner continued to correspond with informants in the Singer Tract until 1948 or ’49 and was advised that one or two birds remained until that time. As Tanner’s temporal distance from his experiences in the Singer Tract grew, so did the distortions in his memory. These distortions are perhaps most dramatically illustrated in an article he wrote entitled “A Forest Alive”, which was published posthumously in Birdwatch (2001), a British magazine. Prominent ivorybill skeptic Martin Collinson mentioned the article and quoted it at some length in a 2007 blog post:

http://proregulus.blogspot.com/2007/12/i-almost-certainly-ignored-this-article.html

Collinson concluded his post with this observation: “As others have pointed out… you can only rationalise the failure of the current searches if you don’t include the words ‘active and noisy’, ‘called frequently’ and ‘easier to see and follow’, in your dataset.”

Of course, Tanner’s observations applied only to the John’s Bayou birds studied in close proximity to a nest. More importantly, Tanner’s recollection was incomplete and inaccurate, and he corrected it in another, humbler, posthumous piece that appeared in Birdwatcher’s Digest (2000) under the title “A Postscript on Ivorybills”. Tanner began by observing that, “Like everyone else’s memory, mine forgets the annoying and unpleasant things and remembers the pleasing; the mosquitoes go but the birdsong remains. Mine is also likely to forget the important and regular events and retain the trivial and unusual.” The article makes it clear that finding even the John’s Bayou birds (which had a known territory and roosting ground) could be difficult and was even harder outside of nesting season. Tanner concluded with this reminiscence: “Hunting in other areas of the Singer Tract for ivorybills was even more difficult and discouraging. My journal is full of such comments as ‘saw old sign, lots of impenetrable vines, and no ivorybills.’ The only other ivorybill we ever found outside of the one nesting pair and their offspring was a single male that we dubbed Mack’s Bayou Pete because of the area he usually inhabited. He was hard to find and once found was soon lost . . . ”  And to reiterate, Mack’s Bayou Pete’s home range was at least something of a known quantity.

By 1985, Tanner was advising the US Fish and Wildlife Service to classify the ivorybill as extinct. He gave the following reasons, to paraphrase:

1) The reports have been unconfirmed and they often describe behavior that is characteristic of Pileateds (flushing from stumps and logs).

Tanner described this as being rare in ivorybills, which may or may not be true, but it’s certainly not unheard of. Allen and Kellogg observed a female feeding on the ground. Moreover, not all reports involved this behavior.

2) There’s so much recreational use of areas where ivorybills used to be present that people should be hearing and seeing them, and there are no extensive areas of former IBWO habitat that are remote and unvisited.

What’s omitted from this analysis is the fact that the beginning of nesting season and the end of deer season are roughly congruent, at least in Louisiana. This means that there’s actually very little human traffic in many prime nesting areas during the times when birds are most active and vocal. And of course, the John’s Bayou area was not particularly remote, although other parts of the Singer Tract were considerably more difficult to reach.

3) Ivorybills are fairly conspicuous birds that, “if present . . . are not hard to find. Furthermore, the feeding sign they made (scaling bark from extensive areas of not long dead limbs and trees) could be easily recognized as a clue to their presence.”

With regard to the feeding sign, I have to wonder what Tanner would say about the sign we’ve found that appears to match this description perfectly. With regard to being easy to find, Tanner’s field notes and his reminiscence in “A Postscript . . .” make it clear that ivorybills were extremely difficult to find, except in extraordinary circumstances – in close proximity to a nest and perhaps with a good deal of habituation to human presence.

Tanner’s story is amazing. His monograph is seminal though not gospel. The in-depth examination of his work in Stephen Lyn Bales’s Ghost Birds is essential reading. Many of his later pronouncements, however, have done a disservice and continue to sow confusion more than two decades after his death.

I’m indebted to Chuck Hunter for alerting me to the Birdwatchers Digest article some years ago, to Fredrik Bryntesson for sharing Herbert Stoddard’s 1936 letter and reminding me of Tanner’s missive to USFWS. This piece is informed by years of discussion with Frank Wiley. He also made a number of constructive suggestions about the specific content. Direct descendants excepted, Frank is undoubtedly J.J. Kuhn’s biggest admirer.

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Sweet Gums to Sweet Gums and More

In this post, I compared scaling on sweet gums in our search area with images of scaling on sweet gums taken by Martjan Lammertink in Congaree National Park; he has graciously granted me permission to post those images and some others here.

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Pileated Woodpecker Scaling on Pine – Photo by N. Banfield/Cornell Lab of Ornithology

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High Branch Scaling on Sweet Gum, Steinhagen, Texas – Photo by M. Lammertink/Cornell Lab of Ornithology

PIWOscaling_M_Lammertink

Pileated Woodpecker Scaling on Sweet Gum, Congaree National Park, Photo by M. Lammertink/Cornell Lab of Ornithology

The focus of the original post was on the direct comparison between known Pileated Woodpecker scaling on sweet gums and the work we are finding in our search area. The differences are quite dramatic. In this post, I will simply include a number of examples of suspected ivorybill work from both our old and new search areas without too much discussion. The differences should be self-evident, even without reference to bark chips. I have come to believe that much if not all of the high branch scaling that Tanner presented as being typical and (by implication at least) diagnostic is not necessarily inconsistent with PIWO work. Thus, in the absence of other indicators, the Steinhagen photos are potentially interesting but not highly suggestive. Note that in all three images of PIWO work on boles, there is clear evidence that the bark has been removed in layers. This is true even on the pine, where signs of this layered work are visible on the left, just above the bird. I now suspect the absence or near absence of layering on extensively scaled, tight barked hardwoods may be the single most important component in the gestalt and may even be diagnostic in itself.

Even when the scaling is quite extensive, the signs of layering are likely to be a giveaway, as in this example from public land near our old search area. The bark chips around the base of this tree were all small and gave further indication that the work had been done in layers.

Presumed Pileated Woodpecker Scaling on Snag, East-Central Louisiana, 2011

Heavily Scaled Snag, East Central Louisiana 2011, Presumed Pileated Work

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Detail Showing Superficiality of Bark Removal – East-Central Louisiana, 2011

Pileated Scaling on Snag - East Central Louisiana 2011

Detail Showing Bark Removal in Layers – East-Central Louisiana 2011

Most of the images below have been discussed in other posts. The scaling is on oaks, hickories, and sweet gums and the differences in appearance should be self-evident.

Hickory4

Scaling on a Hickory Snag, Louisiana, October 2013

 

Hickory3Top

Hickory3

Scaling on a Hickory – Top to Bottom – Louisiana, June 2014

MMHIckory2

Scaling on a Dying Hickory, Louisiana, May 2013

 

Oak1

Oak Scaling, Louisiana, October 2013

 

 

SP5140 scaled hickory (2)

SP5143 scaled hickory (2)

Spscaled hickory (2)

Hickory Scaling, Louisiana 2013 – Photos by Steve Pagans

HairyWPwork

FWHickory1

Hickory Scaling with eyed click beetle and Hairy Woodpecker work. We suspect that there may be a correlation between IBWO and HAWO foraging strategies.


Photo by Steve Pagans

Sweet Gum Scaling, Louisiana, January 2014, photo by Steve Pagans

ScalingNewArea

Hickory Scaling, Louisiana, June 2013

Heavily scaled young oak with suspected IBWO work extending from the base to well up on the trunk. Large bark chips are visible around the base of the tree

Heavily scaled young oak or sweet gum with suspected IBWO work extending from the base to well up on the trunk. Large bark chips are visible around the base of the tree

Extensive Scaling High on a Living Oak, Louisiana, March 2012

Extensive Scaling High on a Living Oak, Louisiana 2012

Detail of extensive scaling on oak

Detail of Extensive Scaling on Oak

Extensive Scaling on Live Willow Oak, March 2012

Extensive Scaling on Live Willow Oak, Louisiana 2012

Scaling on freshly dead oak, East-Central Louisiana, January 2010

Scaling on freshly dead oak, East-Central Louisiana, January 2010. Tree was extensively scaled including lower on the bole. Some bark chips were the size of my forearm

Sweet Gum Scaling, East-Central Louisiana, 2009

Sweet Gum Scaling, East-Central Louisiana, 2009


Recordings from January 2010

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

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

001_FOLDER01_010_Frank 2_10012501_2010_01_25 Audio 6 Witnesses

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

 

Screen Shot 2014-10-17 at 1.35.47 PM

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

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

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

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

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