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IVORY-BILLS  LiVE???!  ...

=> THE blog devoted to news and commentary on the most iconic bird in American ornithology, the Ivory-billed Woodpecker (IBWO)... and... sometimes other schtuff.

Web ivorybills.blogspot.com

"....The truth is out there."

-- Dr. Jerome Jackson, 2002 (... & Agent Fox Mulder)

“There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.”

-- Hamlet

"All truth passes through 3 stages: First it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident."

-- Arthur Schopenhauer

Wednesday, December 15, 2010


-- Project Coyote Update --


The latest update from Mark Michaels of the Project Coyote team in La. is now posted as a pdf, focusing largely on bark scaling/chips in their area, along with other analyses:

You see, they're everywhere.

Everywhere anyone looks they seem to find one.

It's amazing.

So, given the unsearched habitat and some basic math, there must be a population running into thousands.
If there were only a few dozen, they wouldn't be seen and heard as often as they are.
Well, process comments are generally seen as rude, but since these two went first here goes...

(And thanks for the link, Mark; I enjoy our e-mail discussions)

Anyway, our two wags above have demonstrated impeccable technique illustrating a tactic I've noted has become a genuine art form at an educational institution south of here (Brigham Young University, in case anyone is interested).

Find a set of of old clothes and make a trip to a local farmer for a bale of a by-product of the wheat-farming industry. Stuff the clothes full, using a pillocase or cloth sack for a head, paint a face on it, and hoist it on a pole...

One option is to douse liberally with an inflammable such as gasoline; either way, the next step is to apply a match, admire the flame created, and proclaim victory for the forces of enlightenment...

BTW, I saw a flicker in the old ash(?) tree in my backyard about a week ago. It did a hit-and-run for a few hours while a couple of scrub jays were hollering loudly at the intrusion...

I haven't seen it since. Woodpeckers are elusive and secretive critters...
thanks Mark for venturing into La. black bear habitat for your ibwo research. good luck!

valid title even today - "The ivory-bill flies still" by John Dennis
Close, but unfortunately the last Ivory-bill "lies still".

But have a nice holiday season as the world's economy, political systems and environment spiral downward. It is a good time to get out in the woods and get away from it all and if one can justify that with the hopes of seeing an Ivory-bill then more power to you.

how about addressing the fact that the people who go searching tend to find the IBWO (or at least get a glimpse or strongly suspect it to be present) and what this means for the apparent numbers that must be out there. These same people are quick to point out how the bird can perhaps persist in less than optimum habitat as well as pointing out the large swathes of unsurveyed prime habitat still remaining.

So, given the fact that people do find it on their searches (to their own satisfaction at least) in very small fragments of the species potential range, how many do we think are out there?

I have asked this here before of course, and have been ignored or insulted (well, it's kind of an awkward question I guess!)

"woodpeckers are elusive critters" just doesn't cut it. I've seen a good % of the world's woodpeckers on each continent they occur on, and have a good appreciation of what it takes to find them and see them (even if it appears that they 'aren't there').
How in hell is anyone supposed to know how many are out there?

For the record, I'll reiterate. You claim to be a world traveler. Come to Louisiana. You will find that I'm a gracious host and I guarantee that you'll have fun birding, as well as learning just how difficult "ivorybill country" is to explore and survey. Who knows? You might even get lucky and have to eat a little crow. ;-)
You can contact me thru the Project Coyote 2010 email.
By the way, I'm not avoiding the question, I just don't know and wouldn't EVEN hazard a guess at how many ivorybills are left... More than two is all I know for certain. PS... La. is internationally acclaimed for it's Cajun cuisine. There's a little place not too far from the hot zone that makes amazing garballs...
I won't guess either.

I included the possible sighting (and I never asserted I was certain or even that this one reached the level of "my own satisfaction") because full disclosure seemed like the right approach, the nearby habitat looked promising, and I found suggestive, but not fresh, feeding sign in close proximity. The location of the possible is part of a huge habitat patch that includes our search area, which is less than ten miles away. This is contiguous forest, although a river runs through it. There could be only one or two birds in the area, but there could be more. People almost never go into most of these woods, especially outside of hunting season. The mostly unsearched habitat in this part of the state runs into the hundreds of thousands of acres.

Over many field days in this part of Louisiana, I've had one sighting about which I'm personally certain, based on the sound of the wingbeats, not the visual. I'm far less confident about the one from last month. Mentioning it was perhaps a mistake because the rest of the report is of far more consequence.

Come on down.
It wouldn't be a guess. It would be a reasonable estimate based on sightings in areas searched extrapolated to give a ball park figure of birds in unsearched habitat. Nothing complicated. Use as a rough an estimate of potential habitat as you like.

Your certainty of a 'sighting' from wingbeats doesn't induce confidence.
here goes Spat: my wild guess is maybe 6 ibwos in fla, maybe 6 in La and Miss combined and hopefully at least 3 in Ark. thus, my unsubstantiated estimate is less than 20 in Southeastern U. S.
The sound of the wingbeats is referenced in the literature and was recorded in the Singer Tract. It's quite different from the much softer, slower sound a PIWO's wings make when flushed.

Funny: a while back another skeptic who posts here asked why none of the modern reports mentioned the sound of the wingbeats.

Whatever. My personal conviction about the sighting and your lack of confidence are beside the point. The report's primary focus is on feeding sign and scaling. I think I'm onto something; others may disagree. That's fine; if I'm right it will be useful for finding ivorybills, and if I'm wrong, we'll learn more about Pileated foraging, something that's been little studied.

Project Coyote has contended all along that the data we've gathered make a strong circumstantial case for the persistence of the IBWO in this part of Louisiana. We have never asserted we have proof that this is so. Our efforts to obtain that proof will continue. Without proof (and much further study) any "estimate" of numbers is sheer guesswork.
It's not quite guesswork Mark. It would be a reasonable prediction using an estimate of the entire amount of potential habitat left and the number of birds encountered when searching small areas of potential habitat. Just scale it up.

Seeing as the potential habitat is many times larger than that searched, simple mathematics informs us that the population must be fairly substantial - if the reported sightings are genuine, of course.

Additionally, it would only be an overestimate if the bird favours those areas where there have been sightings rather than the unsearched much larger areas. Given the claimed elusive nature of the bird, this seems counter-intuitive and presumably there are more birds per unit area in the much less disturbed unsearched areas, making our rough and ready number an underestimate.

Thanks for the estimate of 20 Bayou. I'm not clear how you've calculated it though? Are you accounting for the large amount of unsearched habitat?

my estimates cover all Southeastern ibwo habitats. not based on any scientific extrapolations, but just a guess based on my ibwo search time, and the realization of the massive public and private areas the birds utilize, and with consideration of the ibwo encounters of other searchers in the S. E. area.
I suspect the lack of engagement is due to the fact that even a very low estimate of the area of potential habitat left points to an astonishingly large number of birds - if the encounter rates and sightings of recent years are genuine of course.
No, I haven't engaged because the questions are not being posed in good faith. You've been harping on this for a long time, and Bill Pulliam quite rightly wouldn't play the game either.

As I said earlier there could be one or two birds in the area, and there could be more. We simply don't know enough about behavior, habitat and home range requirements, or conditions in areas that haven't been searched to make any kind of informed estimate.
Present Ivory-bill distribution and population dynamics were not shaped in a vacuum and are not necessarily correlated closely with just increasing forest biomass, standing tonnage of trees or areals.

There are derivative characteristics of these basic data sets, such as age, standing dead wood biomass, complexity of the forest, and mega-coleopteran community diversity and population that are important.

IBWO numbers were greatly reduced by 1940 and the fledgling rate must have been horrendous due to less than optimal conditions which for many forest characteristics, remains today. Many forest habitats, with relatively simple requirements of sun, CO2 and the lack of saws have recovered in a slightly increasing plot line.

To assume that a rare animal species recovers in a linear relationship to forest area or biomass is exceedingly and erroneously simplistic for many larger species including IBWOs.

This species has more complex requirements than a tree species has and must survive its own wariness (which can disrupt movements) and the synchronous or even excessive increase of predators and roost competitors in the recovering forests.

The uninformed belief that most of us have randomly selected search areas which form the basis for this proposed simple extrapolation is also in error. We often receive some gen on a specific patch or general area and have to search one to several areas totaling ten to twenty square miles or more before we intersect a bird or two on one day of 10 to 50 field days.

The assumption that one can just take the available habitat via models, mappings and aerials and then roughly estimate total numbers is itself not a flawed concept. However one must realize that when some of us report a sighting or possible sighting we may have searched weeks ourselves while standing on the shoulders of others gracious enough to steer us in the right direction after they searched a summated 10 to 50 square miles over a year.

For example we had spoken to people that hunted/visited the Green Swamp environs of FL over decades for ~ 1,200 field days. They separately claimed ~ 4 sightings all in the same two areas. We visited the areas for a week and in a way roughly confirmed there assessment of the areas IBWO usage as very, very low to non-existent. There could be no resident birds in that large area.

We also visited other areas on that survey and covered over 100 square miles with various methods. There may be very few if any IBWOs in this important area of central FL. Then I can chronicle a very few areas that no matter what 10 square mile or 20 square mile area we carefully and meticulously survey we record good to excellent presence data.

We do have maps with pair numbers spatially plotted for certain states but some areas have a number range for pairs or question marks pending data.

The IBWO is not homogenously distributed in open spaces but we do see patterns from positive area to positive area and subsequently, surveying new, large areas is sometimes done more efficiently because of knowledge gained from a prior encounters microhabitat and characteristics.

Merry Christmas all

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