Monday, February 05, 2024

— Why Sound Evidence Is Not Sound! —

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Been a lot of time spent on auditory evidence lately which I almost never link to (my view of auditory evidence has been consistent over the last 18 years) -- it won't move the needle forward for skeptics, who view such evidence as “stringing” people along — and I try these days to focus on evidence that skeptics may find of interest (because in the end they must be persuaded). So a few things:


1)  First, if you haven’t already seen Chuck Hunter’s response to recent views of Mark Michaels see his postings here (which cover some of what I’ll be saying, but with more specifics):


https://www.facebook.com/groups/179784035376368/posts/7439564326064933/?comment_id=7440282235993142&mibextid=c7yyfP


https://www.facebook.com/groups/179784035376368/posts/7439564326064933/?comment_id=7440308122657220&mibextid=c7yyfP


2)  Kents and DK sounds are HIGHLY simple, generic sounds with many sound-alikes in nature from both animals and potential artificial sources. Kents/DKs are not more complex, unique birdsongs or calls as say from a White-eyed Vireo, a Barred Owl, a wren, a Chat, or 100s of other species, so while “earbirding” certainly makes sense in a great deal of birding, it is of uncertain, strained use in the IBWO debate.


3)  The true sample size of IBWO sounds is MINISCULE and recorded on antiquated equipment, possibly producing artifacts that I’m not confident we fully comprehend (though maybe experts do?). There are NO recordings of IBWO DKs at all to go by— zilch — I’ll grant that recordings of other Campephilus DKs (of which there are plenty) are probably adequate for drawing conclusions about IBWO DKs — except that again we have little idea of the range and variability specific to IBWO, which given the generic nature of DKs, makes them hard to generalize about.


4)  The only kent samples we have of IBWOs come from one small set of birds in one place at one time, 80+ years ago — again no good sense of the variability for this species (although there are historically verbal descriptions of different types of kent calls from IBWOs) — in this regard it is interesting how when a putative kent call spectrograpically matches the original Cornell Singer Tract recordings researchers are quick to point that out, but when the match is not as great they fall back on the excuse that the Singer birds were recorded when “agitated” and the call at rest is different — it’s a perfectly plausible explanation, but it also comes off as a case of pounding a square peg into a round hole (or selecting whatever explanation suits one's case in the moment). In short, we don’t have good recordings of enough certain IBWO calls to draw any firm conclusions — and NO, one CANNOT simply assume that calls recorded in the Big Woods, or Choctaw or Pearl or Big Thicket… or… or… emanated from Ivorybills when the presence of the species was never confirmed (lumping all these together may be lumping together apples and oranges until truly shown otherwise)… nor can one assume that ALL other possible sound candidates for such simple sounds have ever been considered or are even known. Sample size is important, and we truly DON'T have it here.


5)  Also, commonly dismissed is the notion of other IBWO searchers in the woodland generating kent or DK sounds that are then picked up by a different group of searchers — unlikely perhaps, but by no means dismissible! (and perhaps no more “unlikely” than hearing IBWOs is!). Anyone who thinks that the only people searching for IBWOs are the few folks reporting on the Web is living in their own self-contained bubble and doesn’t realize how many other individuals, using unknown techniques, are on occasion venturing into remote woodland to search for America’s most iconic species. (…and those are sincere people, let alone any pranksters who deliberately venture to woodland, to make noises solely to befuddle IBWO enthusiasts). Folks are too easily rushing to dismiss the unlikely... when in fact simply encountering the IBWO is itself highly unlikely!...


6)  Again, Ivorybill searchers continually preach to the choir within their own self-contained bubble with evidence often presented by just one person — someone who has already fully-committed to a stance of IBWO persistence and will be perceived, rightly or wrongly (by doubters), as biased or otherwise non-credible. Anyone who is already committed to IBWO persistence who analyzes say, the Luneau video or Mike Collins’ “underflight” video, will be seen as a ‘wishful’ thinker with self-fulfilling analysis and NOT be taken seriously. Instead, such analysis needs to include a co-author who is neutral or even skeptical yet agrees with the writer’s conclusions — and the problem there is that so many neutral/skeptical folks have left the arena wanting to avoid the IBWO debate (it literally could hurt their career!). Hearing the same people, or sort of people, tout the same evidence or sort of evidence over and over and over again has not moved us forward much.


In short, I find recordings of distant kents and DKs verrry problematic, with questionable assumptions made or left unstated. Those (few) that come in direct conjunction with good sightings (almost all of which are brief) are at least somewhat more interesting, but then again comes the endless question of why in 80+ years no active nesthole, roosthole, foraging site, or adequate photo/video has emerged following such evidence… and there too, multi careful-analyses, over decades, of cavities and foraging work, like multi-analyses of kents/DKs, have FAILED to lead us to a single live bird.

Despite the successful degree to which earbirding is utilized for bird counts, bird atlases, eBird, etc. (i.e., common birds), the gold standard by far in the controversial IBWO debate will remain visual evidence.


ADDED:  just to be clear, I’m not arguing that auditory evidence is of no value or should not be submitted and reviewed, but simply that it doesn’t carry the weight for me that others are wanting to give it. I recall certain of Cornell’s Big Woods’ recordings sounding dead-on to my ears as IBWO kents (and even some significant skeptics were impressed by those at the time!) — but those alone would not persuade me of Ivorybill presence there (other evidence did). 


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11 comments:

john said...
This comment has been removed by the author.
john said...

Sound can be used as proof. Cyberthrush is unaware of some advances made in this field as linked below. Worse, for a site that uses the hyperbole "THE SITE", he seems to ignore my research efforts after my work with a volatile individual from South Carolina (the IBWO does not choose who sees it based on their personality, but the evidence was excellent and will stand the test of time). The reader here should understand that there is a lot more going on lately for this species than is discussed at Ivorybills Live!, and I would refer them to the Facebook page Mission Ivorybill which is one of the most professional at the moment.

https://docs.google.com/presentation/d/19RkgzdT4yMPu7cepPEaGqyxf_VrhZNdX4MRFGrpOafQ/edit?usp=sharing

Anonymous said...

The evidence from South Carolina was not excellent and it makes you look unserious when you say that is was.

MikeD said...

The Joshua Nicholson/Saluda evidence was not good.

john said...

Referring to my original comment, and furthermore, there is this paper, withdrawn by the volatile data-owner but still readable on BioRxiv. Cyberthrush was made aware of the paper but did not post or comment about it. Again, it presents excellent evidence and presents it in a manner that is quantitative for the reader-- far better than any casual critique which says it's "not good" but offers no reason why. There are real advances being made in understanding the vocal evidence for the IBWO-- (see version 4)-- https://www.biorxiv.org/content/10.1101/2023.04.06.535925v4.full

cyberthrush said...



John, I don’t link to that work, in part, because the unwillingness of the actual field observer(s) to come forth and be accessible for (frankly intense) grilling on various anecdotal aspects of the claims simply compromises those claims, and you then become the single conduit for the work with no further details and no other (neutral) individual confirming the results/conclusions reached.
Moreover, I believe the original submission to eBird was one of the most embarrassing, least-credible eBird reports I have ever seen! I’ll be happy to cover Saluda claims when/if I ever see significant/substantive/credible/logical (preferably, independently-reviewed!) evidence to support them. (For now, for reasons not worth discussing, I believe the IBWO is extirpated from SC.).
On a more minor note, I do NOT call my blog “THE site...” but only “THE blog…” because it was the 1st (and only) blog to focus entirely on the IBWO and 18+ years later remains the only blog focusing exclusively on the topic… but, no, I don’t link to every IBWO bit or piece that appears on the Web, in fact probably to less than 5% of them, but am always on lookout for new, significant, credible, replicable, scientifically-valid and consistent evidence.
p.s.... these days it literally takes 5 mins. to set up a personal blog or Facebook group where you can put out your own material for consideration as much as you wish...

john said...

Like I said, and it is obvious-- the IBWO does not choose the personality it shows itself to. The papers were valid and the data was excellent.

Anonymous said...

That person is not the reason we think the evidence is extremely poor.

john said...

I find myself writing not so much as rebuttal after rebuttal, but to clarify for a third-party reader of any level. For the interested professional reading this thread, I would refer you to the first comment and these links--
https://docs.google.com/presentation/d/19RkgzdT4yMPu7cepPEaGqyxf_VrhZNdX4MRFGrpOafQ/edit?usp=sharing

https://www.biorxiv.org/content/10.1101/2023.04.06.535925v4.full

One can see the scope and the quantitative level of the work.

Cyberthrush's blog post is incorrect in its basic statement. Sounds of the IBWO are unique, as would be expected from its morphology that is different from nuthatches and the Blue Jay. This difference shows on spectrograms. Just in the past year, here is what has happened with IBWO sounds. The inherent presumptions are logical--
1. that the sounds are different than any other species but are similar to other Campephilus.
2. The sounds accompanied visual sightings by professional expeditions and experienced ornithologists. The IBWO, when sighted, can be an easy ID.
3. In one case, the sound matched the Allen-Kellogg recording of "wokawokas
" (not exactly kents but with some similarities). However, the new sounds did not have the background drone of the large equipment used in 1935.
4. The sounds have a structure of octave harmonics with the fundamental lower than 700 Hz in many cases (n>150).
5. The sounds group around 587 Hz and for Arkansas, 660 Hz. Importantly, these are from multiple professional efforts.
6. Rachel Webster found that sounds she recorded (which have some commonality with suspected recordings from IBWO researcher Michael Collins)
have a "flag" on top of their spectrograms consistent with alarm calls from all other menbers of the genus Campephilus as found on Xeno-canto.
7. Mark Michaels has found that the third fundamental is prominent on suspected IBWO kent calls.

A reader may see vague critiques but nothing of substance (as noted here by "anonymous" and "Mike D"). Why? Because the sound analysis is valid. Read the papers; they will be a bottom line. Sound analysis can be used for ID. The IBWO will have a unique call, once the exact nature is figured out. This is happening now. I do not feel I need to comment further here.

MikeD said...

FYI, since these last comments, Mr. Williams has quietly withdrawn his paper from Biorx.

cyberthrush said...

Hi Mike, and yes I'm aware of that, but just to be clear I believe John withdrew that at the wish of the individual who actually provided/owned the data (it was not John's desire, I don't think, to withdraw it; indeed I think he still stands by it) -- a somewhat confused, odd situation!