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Old Saturday 30th June 2007, 21:48   #11506
Docmartin
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Join Date: Aug 2003
Location: Aberdeen
Posts: 956
Quote:
Originally Posted by emupilot View Post
As for the wingbeat, your data contradicted your hypothesis! You claim that a bird maintaining 8.6 beats per second could be a Pileated, but in none of your test cases does this actually occur. I suspect you are not aware of any case where a Pileated has actually been recorded maintaining the Luneau flap rate, otherwise it would have been in your paper. You can not claim the Luneau bird to be "pretty damn close" to a Pileated wingbeat without a statistical analysis, which I doubt would be friendly to your hypothesis.
I'm glad now that everyone seems to agree that nothing can be conclusively drawn from the Luneau video, because that was really the point of the paper. the Luneau video had been published as conclusive proof of IBWO. It was important to get something published in such a way that even those who believed the sightings could agree that the Luneau bird was not 100% proof. To play the numbers game, which seems to have become popular here, whether you believe the Luneau bird is 90% likely to be an IBWO, or 50%, or 10% or 0% really isn't the issue, as long as it has become evident that 100% is not a tenable option. What has happened since the Sibley papers and to some extent since mine is that the goalposts moved. From 100% IBWO in 2005 we are at the stage where pro-IBWO people say that if there is a 1% chance that IBWOs persist, we have to assume they do and act accordingly. I wouldn't disagree with that, but the point is that 99% of the argument has been won by the sceptics.

For wingbeat analysis... wingbeats 4-11 only became an issue in 2007. In 2005 we were at a stage where the Science paper was stating that PIWOs had never been recorded flapping faster than 7.5 per second, so the Luneau bird could not be a PIWO. It wasn't as if I trawled the web for months to try and find PIWOs that could flap at 8.5 per second. In fact David Nolin's videos were the first and only ones I ever analysed, and they showed very quickly that one central pillar of the pro-IBWO evidence was false. PIWOs could flap that fast when they are taking off in a panic. That was job done as far as my paper was concerned. It went to show just how ropey and uncontrolled the Science paper was, and suggested that the folks at Cornell hadn't tried very hard to analyse any PIWO videos. Then the goalposts moved again, because suddenly it became important to show that PIWOs could maintain that flap rate for at least the 8-9 clear wingbeats of the Luneau video. OK, so someone can go back and someone can try and find a PIWO flapping at 8.5 per second for 8 -9 wingbeats, but notice that we are now arguing over the last 20% of the evidence, the big 80% (showing that PIWOs can and do flap that fast) is over. I wasn't aware of any such videos when my paper was published. I'm feeling pretty confident now that these and other issues relating to the only objective evidence of IBWOs (audio and video) have been resolved and there is no reason to suspect that any of the evidence relates to living IBWOs. It will all come out in the end. SO it comes down to whether or not one believes the sightings. This is always a matter of opinion, but as far as I can see the top birders, and those involved in rarities and record assessment, are tending to smell a big fat rat on those.

btw see this post from the Secret Freezer. That IBWO at 8.6 per second from the archives is not performing an escape flight similar to the Luneau bird. I actually think it very likely it is stood still and fluttering its wings. How shaky is that to base a belief in wingflaps on?
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Last edited by Docmartin : Saturday 30th June 2007 at 21:52. Reason: there's more
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