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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)

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-- Hamlet

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

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Thursday, November 10, 2005

 

-- Symposium Abstracts' Thoughts --

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Just a few thoughts about the Symposium abstracts previously referenced:

The abstracts are interesting, but often only hint at the details that may have been covered in the full presentations. As could be expected many of the abstracts are more indicative of what we DON'T fully know or understand about Ivory-bills than what we do know.

Here is one quote from the abstracts I throw out only to indicate that among principals of the search, unlike the constant armchair debaters over the internet, there is LITTLE doubt what the Luneau video shows:
"Due to technical imperfections, the woodpecker in the Luneau video offers a challenging identification puzzle but comparisons with images of Pileated Woodpecker in flight and a reenactment with models of Ivory-billed Woodpecker and Pileated Woodpecker demonstrate the videoed bird is indeed an Ivory-billed
Woodpecker. "

I am still troubled somewhat by the acoustic data; so far as I can tell there is still no indication that the "kents" recorded in the Big Woods have been compared to the 'toots' of a Red-breasted Nuthatch, the bird Tanner (and I) believe most resembles the Ivory-bill sound (albeit not as loud); only comparisons to the White-breasted cousin are mentioned (this I think is a major lapse if it has not been done). As far as Blue Jay calls go, I see no great problem with the possibility of the taped kent calls emanating from them, since this simply begs the question of why are Blue Jays in the Big Woods apparently producing this call so much more often than they do throughout most of their range. Either this IS a case of mimicry or it is some sort of strange vocal co-evolution in which case one must explain why do Big Woods Blue Jays make the call much more frequently than say Blue Jays in Chicago, Illinois. (Indeed, how many calls do Blue Jays make that are neither part of their normal daily repertoire nor instances of mimicry??? -- does anyone have a clue...)

Finally, I will quote just one abstract below in its entirety, because it so strongly mirrors the conclusions I too have been approaching over the last few years:

"The role of human depredations in the decline of the Ivory-billed Woodpecker"
-- Noel F.R. Snyder
"In virtually all modern accounts, the endangerment of the Ivory-billed Woodpecker has been attributed mainly to (1) extreme foraging specialization, leading to a crucial dependency of individuals on vast areas of pristine woodlands to obtain sufficient food, and (2) the logging of nearly all virgin forests in the species' original range. However, rigorously persuasive evidence for the ivory-bill being an extreme foraging specialist appears to be lacking, and the numerous reports of early abundance of the species across its original range are difficult to reconcile with a dependency of individuals on vast areas of mature forests. Although the ivory-bill did exhibit sparse populations and a frequent close association with remnant virgin forests as it approached extinction, these characteristics may have been due mainly tofactors other than food stress. In particular, direct human depredations may have been more important than habitat modification and food scarcity in producing the species' decline. The loss of certain Florida populations to zealous specimen collecting has long been acknowledged. But in addition, there are other populations for which evidence plausibly suggests extirpation mainly due to subsistence, curiosity, and sport killings. The high vulnerability of the ivory-bill to human depredations was often noted in historical accounts, and no substantial regions are known that were free of such threats. In many regions major ivory-bill declines clearly took place before logging operations were initiated, suggesting that habitat destruction was at most a secondary stress, whatever the primary stress may have been. Logging must surely have greatly lowered the carrying capacity of most woodlands for the species, but not necessarily to the point where food supplies were inadequate to support any ivory-bills. Instead, logging's most significant detrimental role may have been the facilitation of human depredations on remnant populations, especially by providing much improved access to formerly remote regions, a role increasingly recognized as crucial in the current disappearance of vulnerable wildlife species from tropical forests around the world."

-- If 'human depredation' was in fact a MAJOR cause of the IBWO's decline than its end in the 30's would have given the species an extra 20 years to stabilize and hang on while waiting for 2nd growth forest to recover in the 50's; 20 years of crucial 'breathing' time.
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