Ivory-billed Woodpecker (formerly updates) (1 Viewer)

Ilya Maclean · May 24, 2007

dave_in_michigan said:
Excellent content, Ilya. Thanks. But on the basis...

Burden of proof lies with whatever is to be proved. If you want to prove existence, that's one thing. There are ways to prove (with some confidence level) that the bird is not present, and in fact this tends to be the better approach to finding whether they are there or not. That's my real point.

For example on the remote cameras; if you wanted to show with some conclusiveness that IBWO is not present, you might do some statistical analysis on what coverage would be necessary, over what time frame, etc, and come up with a plan to more thoroughly show they are not there with some rigorous statistical confidence. Then suggest the searches do this to really find the bird. If they fail, you've got a strong case the bird is really not there. What you might find, however, is that there is no way to get enough cameras in place to do this. And if that can be shown, then you are demonstrating that searchers should probably stop wasting their time with them.

Personally, I think audio has potential to bring this whole deal to conclusion, not video.

You have some good comments on the items, but they are not yet in the direction of proving them not possible.

At the risk of being psuedo-intellectual...

No, you cannot prove the probability of not an IBWO not being present using remote cameras. You can prove the probability of seeing one, and at face value the probability of not seeing one might appear to be one minus the probability of seeing one, but it isn’t and that is the fundamental reason why science proceeds by rejecting null hypothesis and not the other way round! The whole fallacy of proving a negative yet again!!

Typically when analysing sets of data to detect e.g. a difference, you use statistics to work out the probability of rejecting the null hypothesis - i.e. that the datasets are not significantly different from one another. This is not the same as the probability that they are the same. You could get a high probability value because they are similar, but you could equally get a high p-value because your dataset is too small. Thus, a probability value of 0.05 does indicate that you can be 95% sure they are different, but a p-value of 0.95, does not indicate that you can be 95% sure they are the same.

Edit: Having thought about this a bit longer, I realise what I said before is actually bollix. The probability of non-existance is actually the same as the probability of theoritical occurance, but then not seeing. What can't be proven is the probability of occurance, given non-sightings.

Doesn't negate the fundemental point though. While theoretically the burdon of brief lies where ever you want it to be, the accepted norm is that it lies with those making a claim, and for very good reasons.

emupilot · May 24, 2007

Jane Turner said:
Of course if they had shot their bird, the odds are it would have been an abnormal pileated, and this whole circus would have been strangled at birth.

Yes, of course... the mutant pileateds who say "kent" (in TRE's case) or the pair of mutant Pileateds, one of which had a black crest, as seen for 10 minutes from 30 feet away (in Kulivan's case) and say "kent" as well! Thanks for clearing that up, Jane...

Edward woodwood · May 24, 2007

2) There have been cameras in the best areas for a long time now and there are also game cameras apparently. These are areas where the birds ahem 'live' and still no photo?

Here's Cyberthrush's excuse (no giggling at the back):
birds may indeed be wary of odd metallic man-made objects that suddenly show up on trees (and possibly emit odd sounds on occasion as well??). Or, they may be wary of areas where humans have spent time noisily setting up such objects and returning repeatedly to to retrieve photo disks.

There you go Dave. How can we possibly argue with this level of genius?

Terry O'Nolley · May 25, 2007

Ilya Maclean said:
I think it’s highly implausible that they have learned to change their behaviour, as this would imply they have something on which to base their learning - i.e. a few near misses.

This isn't correct for two reasons.
1) Learned experience during life is not genetically transferable.
2)No bird possesses the language skills necessary to explain to a fledgling that you should hide from humans.

But, having said that, it is entirely possible that any (hypothetically) surviving IBWOs are exceptionally wary because there have always existed some IBWOs that were genetically wary and they were the only ones that survived. Think of it as analogy to antibiotic-resistant bacteria.

tizziec · May 25, 2007

Is there actually anything WRONG with wanting to believe the bird HAS been seen and hoping more are yet to be found? Even if money goes into a wild woodpecker chase, what is so wrong with that? It has helped stop developement, at least for a little while, and perhaps while in search of this ghost other endangered species will be found and areas will continue to be saved from bcoming a concrete hell. What is the big deal with people believing?

timeshadowed · May 25, 2007

tizziec said:
Is there actually anything WRONG with wanting to believe the bird HAS been seen and hoping more are yet to be found? Even if money goes into a wild woodpecker chase, what is so wrong with that? It has helped stop developement, at least for a little while, and perhaps while in search of this ghost other endangered species will be found and areas will continue to be saved from bcoming a concrete hell. What is the big deal with people believing?

Those who are complaining about how much money is being "wasted" on IBWO search efforts suffer from:
Jealousy and Greed - wanting the money to go into their own 'pet' projects instead

djleahy · May 25, 2007

timeshadowed said:
Those who are complaining about how much money is being "wasted" on IBWO search efforts suffer from:
Jealousy and Greed - wanting the money to go into their own 'pet' projects instead

Well, I would disagree. My concern is that we could face a large backlash once the IBWO rediscovery is proven to be a fraud. This would be a big setback for conservation efforts across the board. It doesn't matter that it was an honest mistake, which I think it is; it still looks like a debacle for the outside observer. It doesn't help that this situation has drawn charlatans like **** draws flies.

dave_in_michigan · May 25, 2007

Tim Allwood said:
pseudo-intellectual debate...

Hey now, hold on a minute...

Yeah, ok. Fair cop.

Ilya Maclean said:
No, you cannot prove the probability of not an IBWO not being present using remote cameras. <snip> The whole fallacy of proving a negative yet again!!

And I'll cop to some mistakes here too, without getting myself too deep back into it, along with a little commentary. Certainly no one's ever going to prove extinction with 100% certainty. That's true. I was running (ahead of myself a bit I'm afraid) with the notion that the emerging constraints implied by failures to produce so far are indeed a progress of sorts. (Like Edison's "I haven't failed. I've just found 10,000 ways that won't work.") And also thinking that this narrowing process would be of interest to both searchers and skeptics, albeit for different reasons. New "excuses" might seem endless, but there are practical limitations.

One more attempt at the falsification angle for the skeptic side (and I do think I got this one right)...

The theory of IBWO extinction is strengthened not the slightest by nay-saying about search efforts, but rather by the hard work of searchers failing to find the bird. Skeptics can never prove extinction, but the more thorough and extensive the search without the bird being found, the more probable and strengthened the theory of extinction will be.

Skeptics might reserve a bit of respect to them for that at least.

djleahy · May 25, 2007

Hi Dave,

I think your post speaks to a bit of the disconnect here.

Skeptics do not rely on proof of the non-existence of the bird (as many posters have stated here). They simply note that there is an absence of hard evidence for the existence of the bird.

It's true that the lack of results of the intensive search for the IBWO undermines the case for the existence of the bird. Does this support the case for non-existence? To me, a silly question. Existence is the case to be proved.

Do you understand? A very unlikely hypothesis requires some sort of data to support it to be considered seriously. "I thought I saw something" doesn't qualify.

Bonsaibirder · May 25, 2007

dave_in_michigan said:
For example on the remote cameras; if you wanted to show with some conclusiveness that IBWO is not present, you might do some statistical analysis on what coverage would be necessary, over what time frame, etc, and come up with a plan to more thoroughly show they are not there with some rigorous statistical confidence. Then suggest the searches do this to really find the bird. If they fail, you've got a strong case the bird is really not there.

I have always assumed that remote cameras would be sited in front of the holes most likely to have been excavated or used by IBWOs recently - as judged by the experts on the ground. These are those described as "interesting" or a'holes.

So in my mind the fact that no photos have been produced of IBWOs from these cameras is very strong evidence that a'holes are NOT "interesting". That other species are found visiting a'holes but IBWOs are not, suggests that these other species are probably responsible for the signs that made them "interesting" in the first place. I don't think there are any statistics required here, unless someone wants to propose that IBWOs never return to previously used feeding sites.

Cheers,

Ilya Maclean · May 25, 2007

Terry O'Nolley said:
This isn't correct for two reasons.
1) Learned experience during life is not genetically transferable.
2)No bird possesses the language skills necessary to explain to a fledgling that you should hide from humans.

But, having said that, it is entirely possible that any (hypothetically) surviving IBWOs are exceptionally wary because there have always existed some IBWOs that were genetically wary and they were the only ones that survived. Think of it as analogy to antibiotic-resistant bacteria.

Not sure what you're driving at with this. I never said learning behaviour was genetically transferable, indeed my post implied that it's not (although actually it could be inheritable through imitation). Was simply making the point that if IBWOs have learned to be wary they must have had some experience on which to base that learning - i.e. they must have been shot at, but survived to learn from the experience. In the second part of your post, you more or less say what I said in the post you replied to, but your analogy to anti-biotic resistant bacteria isn't all that relevant because bacteria reproduce at a much more rapid rate than IBWOs and have a much much larger population size and hence gene pool from which to draw.

Ilya Maclean · May 25, 2007

timeshadowed said:
Those who are complaining about how much money is being "wasted" on IBWO search efforts suffer from:
Jealousy and Greed - wanting the money to go into their own 'pet' projects instead

This really isn't the reason. Amongst other things (like undemining the credibility of science, ornithology and conservation) it's about what you can achieve for your money. Although not directly comparible as the pots aren't mutually exclusive, $10.2 million (which is only part of the money spent on IBWO conservation) could buy you an awful lot of rainforest in South America. Back in 2002 (the last date I have figures for), the price of a hectare of virgin rainforest was about $25, so that money could have bought you almost half a million hectares of rainforest. I think very few people would seriously suggest that the benefits of just finding one of species, which is probably extinct and probably can't be conserved even if it's not, outweigh the benefits of conserving such a large area of the most diverse habitat on the planet. Unless of course, the IBWO search effort happens to be a 'pet' project of yours...

dave_in_michigan · May 25, 2007

overstating what is known

djleahy said:
Hi Dave,

I think your post speaks to a bit of the disconnect here.

Skeptics do not rely on proof of the non-existence of the bird (as many posters have stated here). They simply note that there is an absence of hard evidence for the existence of the bird.

It's true that the lack of results of the intensive search for the IBWO undermines the case for the existence of the bird. Does this support the case for non-existence? To me, a silly question. Existence is the case to be proved.

Do you understand? A very unlikely hypothesis requires some sort of data to support it to be considered seriously. "I thought I saw something" doesn't qualify.

Good point, and well stated.

But there is a difference between a skeptic saying they aren't convinced by the information presented and saying (quite vehemently at times) that there is no reasonable way the bird can still persist, or other variations on that claim.

Skeptics here quite clearly make plenty of claims beyond just stating they don't believe the IBWO reports, and anybody making claims ought to be able to back them up. Likelyhood doesn't preclude one from overstating what is known, and overstatements ought to be called out. Skeptics certainly can understand the importance of that principle, right?

Ilya Maclean · May 25, 2007

Docmartin said:
I don't know if anyone still cares... but I had a compelling audio contact with IBWO in Newtonhill, NE Scotland this morning. 2 'kent' calls in quick succession, on putfile here. Am applying for a $$$ grant from USFWS to preserve the area (a bottomland bracken valley bordered by housing). A sonagram is presented on my blog (see sig) compared with Florida 'kents' and those pesky baby deers.

White-tailed Deer matches very well - perhaps a case of convergent evolution? Not sure about the NE Scotland kent though as the frequencies seem a little wrong in places. Could be a different sub-species though. Given the rapid evolution of wariness, I think it's quite reasonable to assume that IBWOs would evolve a slightly different call in NE Scotland, given geographical and concomitant genetic isolation and likely differences in their environment.

With promising audio evidence from Scotland and compelling sightings in Norfolk, is there not a strong argument for relocating the search effort to the UK?

Farnboro John · May 25, 2007

Ilya Maclean said:
White-tailed Deer matches very well - perhaps a case of convergent evolution? Not sure about the NE Scotland kent though as the frequencies seem a little wrong in places. Could be a different sub-species though. Given the rapid evolution of wariness, I think it's quite reasonable to assume that IBWOs would evolve a slightly different call in NE Scotland, given geographical and concomitant genetic isolation and likely differences in their environment.

With promising audio evidence from Scotland and compelling sightings in Norfolk, is there not a strong argument for relocating the search effort to the UK?

Unfortunately I think it entirely likely that this will turn out to be a PSC split and the EIBWO (overweight, oversexed and over here) discovery will have no bearing on the search for the extinct IBWO and CIBWO.

John

Terry O'Nolley · May 25, 2007

Ilya Maclean said:
Not sure what you're driving at with this. I never said learning behaviour was genetically transferable, indeed my post implied that it's not

I apologize, I actually misread your post and thought you were saying that the behavior was plausible.

Ilya Maclean said:
your analogy to anti-biotic resistant bacteria isn't all that relevant because bacteria reproduce at a much more rapid rate than IBWOs and have a much much larger population size and hence gene pool from which to draw.

In a literal sense you are correct. But that is beauty of analogy. If it were literal, there would be no need for analogy.

All I was suggesting was that if most IBWOs were docile/un-wary/etc and some small number of genetic lines were extremely wary, then if there are any IBWOs left they would probably be extremely wary and thus difficult to photograph. I offered that as a rebuttal to mistaken impression that you believed behaviour changes could be imparted via genetics or advanced language skills.

dave_in_michigan · May 25, 2007

Bonsaibirder said:
I have always assumed that remote cameras would be sited in front of the holes most likely to have been excavated or used by IBWOs recently - as judged by the experts on the ground. These are those described as "interesting" or a'holes.

So in my mind the fact that no photos have been produced of IBWOs from these cameras is very strong evidence that a'holes are NOT "interesting". That other species are found visiting a'holes but IBWOs are not, suggests that these other species are probably responsible for the signs that made them "interesting" in the first place. I don't think there are any statistics required here, unless someone wants to propose that IBWOs never return to previously used feeding sites.

Cheers,

Well if they're running say 10 cameras and there are a thousand holes that might qualify as "interesting", then some statistics may yet help to strengthen your position. I have no idea what the actual numbers are. Plenty of pileateds around, so I'm sure there are a very large number of holes to consider, and I'm not convinced that an IBWO roost would be obviously or easily distinguishable from PIWO roost.

emupilot · May 25, 2007

Ilya Maclean said:
This really isn't the reason. Amongst other things (like undemining the credibility of science, ornithology and conservation) it's about what you can achieve for your money. Although not directly comparible as the pots aren't mutually exclusive, $10.2 million (which is only part of the money spent on IBWO conservation) could buy you an awful lot of rainforest in South America. Back in 2002 (the last date I have figures for), the price of a hectare of virgin rainforest was about $25, so that money could have bought you almost half a million hectares of rainforest. I think very few people would seriously suggest that the benefits of just finding one of species, which is probably extinct and probably can't be conserved even if it's not, outweigh the benefits of conserving such a large area of the most diverse habitat on the planet. Unless of course, the IBWO search effort happens to be a 'pet' project of yours...

Your unsupported assertion of extinction aside, your economic argument would require abandoning the Whooping Crane, California Condor, Kirtland's Warbler, and every other endangered species in the developed world in favor of preserving rainforest. The Ivory-bill is incidental in that argument.

dave_in_michigan · May 25, 2007

Ilya Maclean said:
A) Historically at least some of the birds were tame. I think it’s highly implausible that they have learned to change their behaviour, as this would imply they have something on which to base their learning - i.e. a few near misses. It is difficult to disprove an argument that they varied in their tameness historically, but the tame ones have been shot out, but this doesn’t really follow a pattern we see other interbreeding populations of birds.

"Tame" is a bit of colorful exaggeration, right? My understanding is that Tanner reported nesting birds acclimating to their presence. Does the record go further than that? I know about those whacky photos of "Sonny", but I'd discount those as any natural behavior since the bird was a fledgling captured for banding.

Regarding behavior, aren't many of them taught? (I thought that's why reintroduction of lab-bred species can be so difficult). This would certainly reduce the burden that every living IBWO must have learned wary behavior from personally being shot at.

EDIT: sorry, you earlier also gave me this link regarding "tameness".
For that one: those are Cuban IBWO, possible last couple surviving. worth considering, but tough to say these are representative...

emupilot · May 25, 2007

dave_in_michigan said:
Regarding behavior, aren't many of them taught? (I thought that's why reintroduction of lab-bred species can be so difficult). This would certainly reduce the burden that every living IBWO must have learned wary behavior from personally being shot at.

Absolutely. Reintroduced Whooping Cranes and California Condors have to be taught through various mechanisms that people are scary. This is done to replicate the lessons parent birds naturally teach their chicks, although surrogate human parents generally are not as successful at doing that as natural parents are. Reintroduced Condors and Whoopers are far less wary of humans than their natural cohorts.

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