Sunday, January 18, 2009

-- Catching Up --


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The latest open-access internet paper related to the Ivory-bill search making the rounds comes from the University of Georgia and concludes that as few as 5 pairs of Ivory-bills from the early 1900's are all that would be needed for the species to subsist until today. The paper attempts to evaluate the longevity of small bird populations, specifically for "rare large-bodied woodpeckers," given various demographic assumptions. They analyzed various scenarios (in the worse case, extinction resulted within 7 years) to demonstrate the higher-than-acknowledged possibility of the Ivory-bill persisting to today (of course for some of us, the possibility of IBWO persistence is obvious from common sense and the examples of other creatures, without all the statistics and empirical analysis applied ;-)).
The research was funded by the US Fish and Wildlife Service, some of whom are directly associated with the IBWO Recovery Team, so I'm sure the paper's conclusions won't be taken seriously by many who have largely made up their minds on the subject... to whom the authors may one day say, 'we told ya so.' Summary of paper here, if you don't want to read the full academic version.

Speaking of online papers, my current understanding is that Mike Collins' IBWO flight dynamics paper may yet appear over at PLoS at some point (working through some administrative matters) though I don't know a timetable (if Mike or anyone else knows otherwise or has more details feel free to send along a comment/clÄrification).
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15 comments:

Anonymous said...

How about this: you give me $100 now. If the Ivory-bill is ever documented by several different people with good quality photos and video I will donate $1,000 to the conservation organization of your choice. If that sounds good we can work out the details.

Anonymous said...

I know at least several dozen others, besides myself, who would like to take you up on this. Your a brazen soul. Tell us who you are so we can ante up.

Bill Pulliam said...

Gawds, these stupid freekin' betting games again. What possible relevance does any individual's willingness to make those sorts of dumb bets have to do with anything? This is (or at least ought to be) a plain scientific discussion, heated though it might get. So we now have two peer-reviewed papers on the "impossibility" matter, one concluding that even after the extensive and intensive recent search efforts, the statistical upper bound for the global population is still well above zero; another concludes that the possibilities for survival of a very small population over many decades are in fact pretty good. Wonder if those who have previously proclaimed this bird's survival to be essentially impossible based on these factors (i.e. a population small enough to escape detection for this long could never have persisted for this long) will show any shift in their positions now that the premises of their argument have been directly challenged? Unlikely; I've not seen much shifting of positions on this matter by anyone since about 2006 no matter what new information has come along. Meanwhile, the consensus of the broader ornithological community (beyond us noisy online voices) about the evidence gathered so far is that it is ambiguous; neither conclusively proof nor conclusively erroneous. This isn't a matter of "hope" and "faith," it's a matter of judgement based on the total picture. And so we remain amazingly close to where we started... and we keep looking until the last lead goes cold; what else is there to do?

Anonymous said...

and still no bird.

despite the "statistical upper bound for the global population being well above zero."

ho ho ho

although all leads HAVE gone cold, there will never,of course, be a "last" lead.

no wonder this thing has ruined so many reputations

cyberthrush said...

several leads still being checked... ALL leads have NOT gone cold.
And if the species IS extinct there will of course almost certainly be a LAST lead at some point, as with any other extinct bird.

Bill Pulliam said...

Anonymous up there kinda missed the point. The conclusions of that other paper were that IN SPITE of the continuation of "still no bird," there is nowhere near enough data or effort to conclude (statistically) that there really are no birds out there; not even that there are no Ivorybills at all in the Big Woods of Arkansas, by far the most heavily searched area. That's the latest tidbit of science on the matter, like it or not. Of course if your faith leads you to believe otherwise...

Anonymous said...

Aw c'mon; only you "believers" can rely on faith; us "skeptics" use only hard science. That's the way it's always been, and the way it will always be.

Anonymous said...

OK skeptic,

How does the scientist in you explain that the kent recordings made by Cornell in the big woods separate from all known calls when analyzed (scientifically) with acoustic analysis?

If you say the there must be some un-recognized non-ivory-billed call responsible, then does that make you a "believer"?

C Watkins

Anonymous said...

"How does the scientist in you explain that the kent recordings made by Cornell in the big woods separate from all known calls when analyzed (scientifically) with acoustic analysis?"

I don't have to explain it. An unidentified "kent" is not an Ivory-billed sound any more than an unidentified light in the sky is an extraterrestrial spaceship.

"If you say the there must be some un-recognized non-ivory-billed call responsible, then does that make you a "believer"?"

A believer in what? It has already been shown that there are many more "kent" sound sources than has been previously recognized.

What needs to happen here is not for the skeptics to prove the bird is extinct, or for Believers to produce a paper saying there is hope, but for someone somewhere sometime to produce some solid evidence. Lots of rumors. No verifiable evidence. Maybe in another sixty years. Or not.

Anonymous said...

"What needs to happen here is not for the skeptics to prove the bird is extinct, or for Believers to produce a paper saying there is hope, but for someone somewhere sometime to produce some solid evidence."

Of course, this is why the majority of us, in contrast to the perceived great divide between "believers" and "skeptics," are truly "agnostics," sitting on the fence, waiting until more compelling evidence arrives. Thus, we're talking a unimodal rather than bimodal distribution of opinions. Some people just don't get this.

Anonymous said...

unimodal
bimodal

no, some people don't get it. They aren't as clever as you, obviously. They're strictly bimodal, waiting sceptically for something half-decent that warrants taking IBWO survival seriously. Not the pathetic drivel served up as evidence by half-baked scientists (now very quiet and wishing it all away) and dodgy birders (who will be making erroneous identifications as long as they live). None of the evidence so far has amounted to a row of beans.

We don't need 'more compelling evidence', we just need a bird. Anyone of the dozens surviving will do.

until then, it remains entirely reasonable to be ahem, bimodal, rather than delusional.

Anonymous said...

Gee, you've made this so clear, number 6. What we need is a bird, huh? Not compelling evidence. Okay...I'm convinced. Trade in the binoculars and video cameras for a shotgun. We've been delusional indeed.

Anonymous said...

"Gee, you've made this so clear, number 6. What we need is a bird, huh? Not compelling evidence. Okay...I'm convinced. Trade in the binoculars and video cameras for a shotgun. We've been delusional indeed."

How about just reframing what he said to make him evil? Suggest that he wants any living birds killed.

What he meant, naturally, is don't give us a bunch of useless blurry video that is so poor that certain people can see what they want to see. Don't show us bark scaling made by Pileateds, don't produce recorded "kent" calls made by deer, frogs, other bird species or other searchers, don't report unverifiable thrilling rumors. Don't tell us about your claimed double knocks. They are useful only in entertaining believers.

With real birds you don't need "compelling evidence." What we want is high quality video and photos. We want birds that others can see clearly. We want all the field marks and extended views and we want neutral parties to see them. We want the types of evidence routinely gathered with other rare and elusive birds.

It is painfully clear to many of us why views are almost always brief and by True Believers, why conclusive evidence cannot be produced by anyone anywhere anytime by any method regardless of expense. The Ivory-bill is, beyond a reasonable doubt, extinct. As in other fields it is easy to string along believers, the gullible and the uninformed, but birders are moving on to other things. Check out the Birdforum Ivory-bill thread. Nothing to report, people have moved on and the story is fading with a whimper.

Anonymous said...

"Check out the Birdforum Ivory-bill thread."

Yeah...the final authority for many here...and why are YOU even here?

Anonymous said...

"Check out the Birdforum Ivory-bill thread."

Yeah...the final authority for many here...and why are YOU even here?


Nobody said Birdforum was the final authority. It certainly was not when it was loaded with believers and it's not now.

I am here because the topic interests me.