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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

Tuesday, November 10, 2009


-- Pulliam Wrap-up (on Tenn.) --


Bill Pulliam has put up his final post on the Tennessee goings-on, essentially asking for suggestions and giving his own thoughts on how best to proceed in the next season (what works and what not so much). He plans to concentrate his limited time at Moss Island in February-March:


(Nothing in this post, btw, about the Pearl videos, but no doubt Bill will have more to say on that in the future.)
I'm sure we wish Bill (and any other Tennessee searchers) good luck ahead. IF Ivory-bills exist in Arkansas I believe the chances of them being in west Tennessee are quite real (indeed more real than in the Pearl); but if there are no IBWOs in Arkansas (and I'm still debating that in my own mind at this point), than I'd find the Tenn. chances very slim.

If any Ivory-billed Woodpeckers yet exist, they are likely 'functionally' extinct. If we find them, recovery efforts will be made (because that's what we humans do... after we devastate a species), and they will likely be futile. If we are unwilling to set aside huge tracts of land from human encroachment for these and other creatures (and we are unwilling to do that, opting instead for 'management') than any future for them seems bleak. My best hope is that we find them, so that we can, in a sense, say our final farewells, and just maybe learn something in the process that will assist us in dealing with the 1000's more species now headed their way.
And lastly, my hats off to all those who work so assiduously and selflessly, in any capacity, in conservation. Even with the occasional successes, rewards, the good people, the constant hope, any progress is very slow and almost miniscule compared to the burden-at-hand; the depressing moments and days must be abundant. Thanks for all you do....
I don't view myself as cynical which is how Cyberthrush's comments on the subject of extinctions appear to me. The issue of whether the Ivorybill is "functionally extinct" is a valid and troubling one, of course, which is doubtless one of the questions that drives people like Mike Collins on his incessant search. In reviewing the commentary so far on several sites, everyone has been universal in their praise of his perseverance, which I see as a welcome trend.

To swing the extinction discussion in a more upbeat direction, I note that the wild population of whooping cranes numbered 21 in 1941 and 340 now.

Not the elixer for wild optimism, but the right direction nevertheless...

Anyway, here are a couple of video links to what many regard as another troubled species (okay, I'm a sucker for predators in case anyone hasn't figured that one out). I've got a twofold reason for including these; over on the IBWO forum, opreys were listed as a possible--and plausible, IMHO--candidate for the bird in Mike's Nov. 5 video. Someone dismissed this with the comment, "Raptors don't fly that way," but ospreys are on my very short list of rare birds I've seen in the wild. Twenty years ago I was flyfishing in the Lake Almanor region of Northern California, and I was treated to a display by Nature's original fly fisherman complete with its own effective use of hooks and feathers...

So there's that aspect, plus this is some pretty incredible footage regardless (apologies if you've seen them before).



Anyway, the tale shape of the bird in the Nov. 5 video is what really troubles me. By contrast, I'm smitten right now by the Nov. 3 "flying towards the camera" vid, and for those who suggest RHWO as a possibility, I note that near the end there appears to be another much smaller bird that flashes in briefly on the right, and that one does appear to be a RHWO. This is consistent with Mike's account of numbers of RHWO's being present in his search area.

If that proves to be the case, and I think size comparisons and measurements will determine that one, then we may have to conclude that's an awfully big bird we're seeing with a lot of white in the right places.
CT, its common place, almost expected of bloggers, to use various methods inclusive of hyperbole, exaggeration, rationalization, etc, to provoke chatter. Good job.

Your beliefs are based on limited information and field knowledge or experience of what exactly the raw data is to estimate the IBWO meta-population sizes and where they are.

Various field efforts have different methods and different ultimate goals than pursuit of pictures and media consequently “blog ready sound bites” are limited from some quarters.

Some of the areas you mention above as being barren almost surely have Ivory-bills according to data several have gathered in various states if indeed you value good reports by competent birders as you profusely pronounce to do. Some areas you write off are curiously the same areas that you ask information on, inferring your knowledge of these areas is limited …..yet you assert strong conclusions.

Are numbers in even a few superior, large patches at anything like one pair per 15 square miles?…..possibly, or one pair per 50 sq miles in catastrophically impacted habitats in the gulf coast plain, or in long, narrow linear habitats with too much margin and GHOWs?….no. However there is a mosaic of habitat that can and has supported IBWOs, the relative quality closely associated with specific characteristics in today’s admittedly resource depaupered forests…….dbh, seclusion, anastomozing bottoms, standing dead wood, incidental take rate, nest tree availability, predator community, coleopteran community, Elapidae density, browse rate, feral animals, disturbance thresholds, etc. all determine an areas carrying capacity. The main point is....…there is carrying capacity and there are some birds.

Are there 100 birds or even more as some overzealous searcher claimed years ago…….sadly he was a blind optimist. The number is evidently less, perhaps as low as 30. Indeed numbers in 1938, at least 40, counting the 12 birds missed by Tanner in MS, could have subsequently dwindled to a dozen birds until some, small, mild recovery began post ‘70s. Ambient discoveries of IB by Kulivan, those in AR, and another locality weakly infer some recent, slight increase in population.

Considerations that can keep any estimate erroneously depressed is the extremely low detection rate of birds for the inexperienced and those without advanced field methods.

Efforts that employ stealthy field methods have acceptable results yet sometimes the perception of these results is exasperating. Participants sometimes seem disappointed that a survey event produced only 1 or 2 good audible contacts from 1 or perhaps 2 birds. In a week if 3-5 researchers achieve an acoustical footprint of 10 square miles they have hustled. One contact in that week approaches the maximum expected response as far as pair numbers that have perceived the applied attraction methods. It also indicates a tolerbale population density.

No the jury is not in on extinction or functional extinction. If experienced individuals are seeing or hearing pairs at a rate ~ constant with the number of sightings of single birds that doesn’t show the population demographics of a functionally extinct species.

Artists that are newbies at forensic video artifact analysis or bloggers with no direct field experience with recent DKs, kents and sightings are not listed under Wikpedia as either God, able to predict homozygosity, or as being on the Black Robin restoration team.


F. Virrazzi
Here are two key questions:

Have competent observers who have reported definitively seeing Ivory-billed Woodpeckers actually seen the bird?

Are double-knocks made by Ivory-bills and can observers competently report what is and is not a Campephilus double-knock?

I really don't think that birds disappearing from where they were detected has any bearing on the answers to the above questions. If we were to assume that birds not found have died, we might as well assume it went extinct when the Singer Tract was logged. Is there really something special about this decade that they would dwindle now after 60 years of improving conditions? Or does the persistence of the Ivory-bill still rely on the original thesis that the bird is mobile and very rare?
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