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new paper on the Ivory-billed Woodpecker (3 Viewers)

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fishcrow

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Over the years, there have been many posts here about the Ivory-billed Woodpecker. Discussions of this topic have unfortunately been marred by individuals who have nothing more than misguided opinions to offer. If anyone is interested in reading about direct observations and evidence for the persistence of this magnificent bird, a paper that was recently published may be accessed near the top of the page at my website fishcrow.com.

It is no secret that this issue is controversial, and there is no way that the quantitative arguments in the paper would have been published in a statistics journal if they were anything less than rock solid. The public policy aspect of the journal opened up the possibility of including the material on the folly and politics that have undermined the conservation of the Ivory-billed Woodpecker for decades.

My website also has links to reports of observations of birds during trips to the Arctic and other locations.

Mike Collins
Alexandria, Virginia
 
Cheers:t:

Maybe i won’t have to Cuba for their subspecies after all but i still need the cigars;)

I haven’t ‘refreshed’ my IBW mental page for a while so this is timely and there are some additional trip reports from places i will never be able to visit so i might as well bird vicariously:t:

Laurie -
 
It is no secret that this issue is controversial, and there is no way that the quantitative arguments in the paper would have been published in a statistics journal if they were anything less than rock solid.
Mike Collins
Alexandria, Virginia

Actually, as long as the statistics appear solid, it is very unlikely a statistician would be able to spot the fundamental flaw in the premise of the paper, but BF has a huge amount of experience with this tired argument:

https://www.birdforum.net/showthread.php?t=33968&highlight=ivory+billed+woodpecker

Nothing has changed. Nothing to see here, move along.

John
 
"Discussions of this topic have unfortunately been marred by individuals who have nothing more than misguided opinions to offer."


Those who are capable of thinking for themselves can review the information that is laid out in the paper and make their own decisions.

See top....

John
 
Lies, damn lies and statistics—
Garbage in, garbage out (which, I think, might be the case here)—
Etc, etc—

Definitely count me a skeptic, but wouldn’t it be glorious if the author’s right and a viable population of Ivory-bills still survives somewhere in the remnants of its old habitat?
 
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Lies, damn lies and statistics—
Garbage in, garbage out (which, I think, might be the case here)—
Etc, etc—

Definitely count me a skeptic, but wouldn’t it be glorious if the author’s right and a viable population of Ivory-bills still survives somewhere in the remnants of its old habitat?

For some applications of statistics, there is some truth in the quote, but it's a clear cut case in the analysis of the flyunder video. The bird in that video is a large woodpecker according to an expert on woodpecker flight mechanics, but the input of an expert isn't really needed -- anyone can study the video and confirm that it has the distinctive wing motion of a large woodpecker. The flap rate is ten standard deviations greater than the mean flap rate of the Pileated Woodpecker. That leaves only one possibility.

One of the videos is analyzed using a simple but powerful concept in probability. As mentioned in an example from poker in the paper, it isn't all that rare to be dealt a full house, but the probability of being dealt a full house several times in a row quickly becomes astronomically small as the number of hands increases. Similar reasoning is used by criminologists to quantify DNA evidence. One of the videos shows a series of events involving highly unusual flights, a double knock and other behaviors, field marks, and body proportions that cannot be attributed to any other species of the region.

I am right, and the truth always eventually prevails. In this case, however, there is a chance that the truth won't prevail in time to save the Ivory-billed Woodpecker from extinction.
 
For some applications of statistics, there is some truth in the quote, but it's a clear cut case in the analysis of the flyunder video. The bird in that video is a large woodpecker according to an expert on woodpecker flight mechanics, but the input of an expert isn't really needed -- anyone can study the video and confirm that it has the distinctive wing motion of a large woodpecker. The flap rate is ten standard deviations greater than the mean flap rate of the Pileated Woodpecker. That leaves only one possibility.

One of the videos is analyzed using a simple but powerful concept in probability. As mentioned in an example from poker in the paper, it isn't all that rare to be dealt a full house, but the probability of being dealt a full house several times in a row quickly becomes astronomically small as the number of hands increases. Similar reasoning is used by criminologists to quantify DNA evidence. One of the videos shows a series of events involving highly unusual flights, a double knock and other behaviors, field marks, and body proportions that cannot be attributed to any other species of the region.

Yes, yes, I read the article too. . .. You aren’t its author by any chance?

I am right, and the truth always eventually prevails. In this case, however, there

Wow, nothing “probabilistic” about that statement! Do you know the “truth” about everything or just Ivory-billed Woodpeckers?
 
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The bird in that video is a large woodpecker according to an expert on woodpecker flight mechanics, but the input of an expert isn't really needed -- anyone can study the video and confirm that it has the distinctive wing motion of a large woodpecker. The flap rate is ten standard deviations greater than the mean flap rate of the Pileated Woodpecker.

The only important question is whether that puts it outside - statistically - any of the possible alternatives, not in terms of means, standard deviations or any other statistical matter, but actual measured variation. If not, game over: proves nothing. If so, back to measuring the accuracy of the measurements and their repeatability.

Oh yes: and whether anything else suggestive of the species claimed is visible on the videos. IIRC that was never the case.

Does it?

John
 
...not in terms of means, standard deviations or any other statistical matter, but actual measured variation.

Means and standard deviations actually do come from measurements. In this case, those statistical quantities are used to rule out the Pileated Woodpecker.

I'm going to revert back to my initial intention, which was to post an announcement of the paper and then be done with it. If anyone is interested in the conservation of the Ivory-billed Woodpecker, it would be best to review the information that is laid out in the paper.
 
Means and standard deviations actually do come from measurements. In this case, those statistical quantities are used to rule out the Pileated Woodpecker.

I'm going to revert back to my initial intention, which was to post an announcement of the paper and then be done with it. If anyone is interested in the conservation of the Ivory-billed Woodpecker, it would be best to review the information that is laid out in the paper.

This is the best technique to help the IBWO:

https://en.wikipedia.org/wiki/De-extinction

cheers, a
 
I followed the ivory bill thing with excitement some years ago, but after everything from human to mechanical audio monitors to cyber video cameras were planted for even more years without producing a single positive ID, you have to accept that the species is gone. As far as Cuba goes, I don't know if a sizable edible bird like that could have still persisted after Castro. Well OK, it is possible because the Cuban timber industry would have been destroyed along with all the others.
 
Birds fly funny sometimes. Any birder will tell you that. It catches us out every now and again. You need more than "it flew funny so it must have been the extinct one" to get the people who know how to find and identify birds (birders) looking for Ivory-billed Woodpeckers again I'm afraid.
 
I followed the ivory bill thing with excitement some years ago, but after everything from human to mechanical audio monitors to cyber video cameras were planted for even more years without producing a single positive ID, you have to accept that the species is gone. As far as Cuba goes, I don't know if a sizable edible bird like that could have still persisted after Castro. Well OK, it is possible because the Cuban timber industry would have been destroyed along with all the others.

Upon assuming power in 1959, Fidel Castro’s government began to implement an aggressive national reforestation program. In large measure this program responded to a grave national concern given the country’s deforestation trend.

From the time of discovery to 1959, the total amount of land area forested in Cuba had declined from 72 percent to 14 percent. As a result of the reforestation program initiated in 1959, by 1992, according to official estimates, the amount of land area forested had increased to 18.2 percent of the national territory. This 30 percent increase was achieved partly through better management of timber harvesting rates but principally through reforestation. Of the total area forested in 1992, natural forests accounted for 84 percent, or two million hectares. Two-thirds (67.6 percent) of national forests were set aside as protected areas, while one-third (32.4 percent) was used for timber production. Between 1959 and 1992, the net annual addition in forested land area approached 14,000 hectares.

By 2016 the forest cover had reached 30.6%

Happy to help with regard to your lazy assumption regarding Cuba.
 
Birds fly funny sometimes. Any birder will tell you that. It catches us out every now and again. You need more than "it flew funny so it must have been the extinct one" to get the people who know how to find and identify birds (birders) looking for Ivory-billed Woodpeckers again I'm afraid.

Its not even a matter of flying funny: its a question of the maximum and minimum flap rates (which are naturally related to activity, either climbing from a standing start or maximum/minimum flight speeds). Unless there is no overlap - which is unlikely for similar sized congeners - all the statistical analysis in the world will not prove anything other than there is overlap.

John
 
I have posted a lecture that expands on the material in Sec. 6 of the paper that recently came out in Statistics and Public Policy. The public policy aspect of that journal made it a good fit for material on the folly and politics that have impacted this conservation issue. For example, the editors of some of the leading science journals failed to provide diligent oversight on this issue.

The analysis of the 2008 video is based on an assessment by the leading expert on woodpecker flight mechanics and the statistics of avian flap rate. The expert concluded that the bird in the video is a large woodpecker (any bird watcher can come to the same conclusion by studying the distinctive wing motion). Only two large woodpeckers occur north of the Rio Grande, but the flap rate and flight speed are both well outside the range of the Pileated Woodpecker. A reviewer of a submission to PNAS tried to explain away this inconvenient fact by suggesting that the speed of the video had been altered in order to increase the apparent flap rate and flight speed.

By making that baseless accusation, the reviewer essentially conceded that the bird in the video cannot be a Pileated Woodpecker. The flyunder event is embedded in nearly an hour of digital video. It would have been easy for PNAS to have confirmed that the video is legitimate, but the editor simply took the word of the reviewer.

Mike Collins
Alexandria, Virginia
 
It is important for non Yank birders to realise what a big ‘Country’ (my favourite Western btw) the USA is compared to the tiny overcrowded bit of rock we perch on. I like to remain positive but the one thing that is undeniable is that it is quite a large bird to overlook for so long - i take my hat off to those who venture into Deliverance County to search for them:eek!:

As for Cuba - i had better get over their before fine Havanas become endangered;)

Laurie -
 
Its not even a matter of flying funny: its a question of the maximum and minimum flap rates (which are naturally related to activity, either climbing from a standing start or maximum/minimum flight speeds). Unless there is no overlap - which is unlikely for similar sized congeners - all the statistical analysis in the world will not prove anything other than there is overlap.

John

Largely agree, but Ivory-billed and Pileated are not congeners.

Andy
 
Largely agree, but Ivory-billed and Pileated are not congeners.

Andy

Fair point, but actually they are even closer in size than I thought, with Pileated butting up to minimum IBWO and overlap in wingspan. Simple physics (always a better guide to aerodynamics than statistics) tells you the performance is going to be as similar. :t:

John
 
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