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Ivory-billed Woodpecker evidence published (1 Viewer)

fishcrow

Well-known member
Video footage of several events involving flights, behaviors, field marks, and other characteristics that are consistent with the Ivory-billed Woodpecker but no other species has now been published in the following papers:

Paper #1 discusses audio recordings and some of the evidence (supplemental material).

Paper #2 discusses conservation issues and all of the evidence.

Paper #3, which came out today, discusses double knocks, wingbeats, and some of the evidence.

This work was recommended for publication by experts in ornithology, conservation, avian flight, and bioacoustics. Nobody has identified any flaws in the analysis or proposed a plausible alternative explanation for any of the events in the videos, which were obtained during encounters with birds that were identified in the field as Ivory-billed Woodpeckers at sites where these birds had been reported. Anyone who wishes to get at the truth would be wise to ignore unsupported opinions, study the evidence, and come to their own conclusions. Presentations of the evidence in lecture format may be accessed at my website. I am about to depart for a month at sea in the Arctic and won’t be available for questions, but the answers are contained in those papers.

Mike Collins
Alexandria, Virginia
http://fishcrow.com
 

Andy Adcock

Well-known member
England
Hmmm,
not sure this would pass scrutiny of the committee in the UK?

Get a net accross that river and catch one, that would end the argument once and for all.



A
 

Farnboro John

Well-known member
Fishcrow is just one of the usual suspects from the old mega-thread, isn't he?

Nothing new in the assembled documents.

John
 

Jack Dawe

Well-known member
Here we go again. |=)|

Getting a paper accepted for publication doesn't mean the author is right. I know of a case in a completely different discipline where an academic built a whole reputation around a pet theory. It was controversial, but he didn't consider any of the counter-arguments plausible - not until 40 years later when eventually someone comprehensively blew his theory out of the water and further evidence blasted it to smithereens while still in mid air. Had to feel sorry for the guy, but I guess that's what tends to happen when your theories are not grounded in any incontestable proof.
 

birdmeister

Well-known member
United States
The author presents some interesting evidence in the case, but I still think that there's nothing yet to actually prove the Ivory-billed Woodpecker's present existence.

Of course, I have not ruled anything out, but I almost certainly won't be convinced unless there are clear photos and/or video.
 

lewis20126

Well-known member
Double-knocks in the genus Campephilus

https://en.wikipedia.org/wiki/Campephilus

Abstract:

Most, if not all, of the extant members of the genus Campephilus communicate with loud double knocks and in the author's experience of the Neotropical species, where present, these species are easily detected by these knocks and their vocalisations. Whilst the species are often somewhat shy they are frequently very responsive to playback of these vocalizations and even manual efforts at imitating the double knocks.

On the basis of vocalization evidence alone, or the lack of it, the author finds it inconceivable that a large member of this genus could elude detection in the southern United States.


cheers, a
 

davercox

Dave Cox
Supporter
Thank you for the Wikipedia link, Alan. In there we find

"Louisiana 2006/2008
Dr. Michael Collins reported nine sightings of Ivory-billed Woodpeckers in the Pearl River in Louisiana in 2006 and 2008, including an encounter in which kent calls came from two directions at the same time, and an additional sighting (of two birds) in the Choctawhatchee River in 2007.[6] Three of these sightings are supported by video evidence. Additional analysis of these videos was published in an earlier paper, along with comments by independent experts.[44] Bret Tobalske, an ornithologist who specializes in the flight mechanics of woodpeckers, performed an analysis of wing motion and concluded that the bird in the 2008 video is a large woodpecker. Only two large woodpeckers occur north of Mexico, but the flap rate is about ten standard deviations greater than the mean flap rate of the pileated woodpecker. The flight speed, narrow wings, and prominent white patches on the dorsal surfaces of the wings are also consistent with ivory-billed but not pileated woodpecker. Avian artist Julie Zickefoose analyzed the 2006 video and commented on the "rared-back pose, long but fluffy and squared-off crest, and extremely long, erect head and neck" and an unusual short flight that does not seem to be consistent with a pileated woodpecker. A size comparison was carried out using part of the tree in which the bird in the 2006 video was perched.[6] Two forks made it possible to scale frames from the video relative to a photo of a pileated woodpecker specimen that was mounted on the tree. On the basis of the comparison, it is clear that the bird in the video is a large woodpecker, and the size appears to be consistent with an ivory-billed woodpecker. The 2007 video shows events involving a woodpecker delivering a blow that is accompanied by an audible double knock, unusual swooping flights that are consistent with historical accounts of the ivory-billed woodpecker, and a takeoff with deep and rapid flaps that are similar to the flaps of the closely related imperial woodpecker (Campephilus imperialis) taking off."

I think fishcrow's new post relates to these sightings, so in itself nothing new here. Possibly Dr Collins wanted to bring them to a wider audience.
 

lewis20126

Well-known member
Thank you for the Wikipedia link, Alan. In there we find

"Louisiana 2006/2008
Dr. Michael Collins reported nine sightings of Ivory-billed Woodpeckers in the Pearl River in Louisiana in 2006 and 2008, including an encounter in which kent calls came from two directions at the same time, and an additional sighting (of two birds) in the Choctawhatchee River in 2007.[6] Three of these sightings are supported by video evidence. Additional analysis of these videos was published in an earlier paper, along with comments by independent experts.[44] Bret Tobalske, an ornithologist who specializes in the flight mechanics of woodpeckers, performed an analysis of wing motion and concluded that the bird in the 2008 video is a large woodpecker. Only two large woodpeckers occur north of Mexico, but the flap rate is about ten standard deviations greater than the mean flap rate of the pileated woodpecker. The flight speed, narrow wings, and prominent white patches on the dorsal surfaces of the wings are also consistent with ivory-billed but not pileated woodpecker. Avian artist Julie Zickefoose analyzed the 2006 video and commented on the "rared-back pose, long but fluffy and squared-off crest, and extremely long, erect head and neck" and an unusual short flight that does not seem to be consistent with a pileated woodpecker. A size comparison was carried out using part of the tree in which the bird in the 2006 video was perched.[6] Two forks made it possible to scale frames from the video relative to a photo of a pileated woodpecker specimen that was mounted on the tree. On the basis of the comparison, it is clear that the bird in the video is a large woodpecker, and the size appears to be consistent with an ivory-billed woodpecker. The 2007 video shows events involving a woodpecker delivering a blow that is accompanied by an audible double knock, unusual swooping flights that are consistent with historical accounts of the ivory-billed woodpecker, and a takeoff with deep and rapid flaps that are similar to the flaps of the closely related imperial woodpecker (Campephilus imperialis) taking off."

I think fishcrow's new post relates to these sightings, so in itself nothing new here. Possibly Dr Collins wanted to bring them to a wider audience.

Dave , thanks. Wikipedia IBWO has been repeatedly targeted ('edited') by IBWO believers and I'm not sure anyone can be bothered to re-edit, caveat or other these days.

cheers, alan
 

Andy Adcock

Well-known member
England
For anyone interested, here's a link to the Cornell site where the various 'search' findings are summarised

http://www.birds.cornell.edu/ivory/folder.2010-04-20.2993097079/

Regarding the so called 'Kent' call, a paragraph at the same site writes

White-breasted Nuthatches have a call that is similar, but less powerful. Blue Jays also sometimes make sounds that resemble the calls of Ivory-billed Woodpeckers. Researchers use computer programs to analyze the acoustic properties of the sounds and classify them as most similar to the calls of Blue Jays, White-breasted Nuthatches, or Ivory-billed Woodpeckers.



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Well, Klaas van Dijk I think the reasonable explanation of why there is much difficulty in seeing this bird, let alone photograph it. Is due to the fact that it's habitat in which it is found nowadays in is very difficult to navigate through on either boat or foot. Another thing is, after James Tanner's research, he estimated a pair of Ivory-bills could have a territory of up to 6 sq mi, about 9.66 sq kilometers. Also another thing is , it is believed that this bird is very skittish and gets on alert at a much farther distance that when a Pileated Woodpecker does. With, as you said, over a thousand people are cramming into these small expanses of Tupelo/Cypress swamps, the birds will become increasingly stressed and then they will leave most likely to find a more suitable place to live. I hope this answers your question.
 

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