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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.
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"....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






Thursday, November 12, 2009

 

-- Just a Ramblin' Kinda Guy --

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Steve Martin used to stand on stage with an arrow through his head and a banjo in his hand, and explain that he was just a ' 'ramblin' sorta guy.' ...That's kinda how I'm feelin' these days (...without the banjo) --- so I may post a few days of ramblin' entries, 'bout things just rattlin' 'round my brain (there are many) at this point:


We'll start with Ivory-bill sounds... Lots and lots of claims by now for possible kents and double-knocks heard in search areas (indeed many recorded); even a few cases of kents and double-knocks heard in conjunction, or better yet sightings and sounds in conjunction. But still, over the entire last 4 years most sounds seem to be heard largely in isolation (with the occasional short series), and upon daily followup often not heard at all.
I'd be curious to find out what we know about the repetitiveness or rate of calling or double-knocking for Ivory-bills historically, or other Campephilus species (if there is too little data for IBWO). I would've expected more sounds by now; much more.
During the breeding and pre-breeding months (Jan. - April) I think one can go onto Pileated-established territory and through the day hear repeated calls from these birds. The sparse and isolated sounds of supposed Ivory-bills from many of the search areas doesn't seem normal, and is as troubling as the sparseness of the sightings. It argues for the likelihood that the sounds are not coming from live birds but from other more random sources. Or do Ivory-bills fail to 'communicate' much or regularly because they lack counterparts to communicate with? (One can always come up with explanations.)


The photo problem is similar; should there or shouldn't there be a better photo by the end of 4+ years? These large birds no doubt engage in extensive and significant foraging activity. Methodical categorizing of promising foraging sites as well as cavities in several of the search areas has been done (granted the land tracts involved are huge and many such sites may be easily missed), followed up with either remote camera or live human monitoring of the sites... and not a single adequate picture. Yes, the chances may be small of photo capture, but we only need ONE picture; not 10 or 5 or even 2, just ONE decent picture in 4 years of watching methodically, carefully-chosen sites; it is not encouraging.
As I try to wrap my brain around how the last 4 years of data sync with the previous 60 years, various issues and disconnects come to mind. If other news doesn't intervene I may ramble through some of 'em in ensuing days. People sometimes get bogged down in minutia, and possibly miss the bigger picture which is more telling....
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Comments:
Having heard Campephilus double-knocks myself, I give alot of credence to reports of double-knocks from people who are familiar with them. They are really that distinctive. We know that their occurrence is concentrated at the beginning and end of the day and they only occur in Southern bottomlands.

Bill Pulliam did a thorough analysis to look for another source for his double-knocks, but concluded they were of biological origin. Is there any other credible hypothesis other than an Ivory-billed Woodpecker? That doesn't mean it is one just because we don't know what else could have done it, but I think it's hard to discount when the alternative is... nothing. A control test ought to be done with ARU's to see if credible double-knocks can be recorded outside of Ivory-bill range - if that comes up with something positive then we would have evidence for an alternate hypothesis.

As for the Big Picture, the appearance and disappearance of putative Ivory-bills is not a good sign. Rather than an established permanent population like at the Singer Tract, the observations are consistent with wandering individuals or pairs which apparently can't be sustained indefinitely by one patch of habitat.
 
I thought doing an ARU test somewhere far from IBWO habitat was a good idea at one time, but I have doubts on what sort of reception the test results would receive compared to the effort and expense of doing the test. The results would probably only elicit yawns because they would certainly be negative, and probably wouldn’t convince anyone of anything. It’s easy to think of a hundred "stump the chump" questions to ask the presenter of those results, like, "How do you know that maritime traffic on the Mississippi Delta makes the same sounds as maritime traffic on the Puget Sound?"

The results would certainly be negative because if there was a double-knocker in the woods of New England or the Pacific Northwest, we'd know about it already. Strange, loud, repetitive sounds get investigated by loggers and hunters and other people that live there. If there was an effort made to find another source of the mystery double-knocks, it should be more along the lines of talking to the people that live and work in Southern forests. If there’s something else that makes that sound, loud and repetitively, someone there would know what it is.
 
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