Ivory-billed Woodpecker (formerly updates) (25 Viewers)

[Snowy1]

You may have hit the nail on the head Naples, seeing as the Ivorybill is a bird of the treetops. I once watched a Nature segment on raptors and they had mounted a camera on the head of a Hawk. Anyhow, the idea is a little far-fetched I admit.
We're just going to have to get out and do some real heavy slogging. I know that it's not everybody's cup of tea but it really is the only way.

 

[cyberthrush]

You may have hit the nail on the head Naples, seeing as the Ivorybill is a bird of the treetops. I once watched a Nature segment on raptors and they had mounted a camera on the head of a Hawk. Anyhow, the idea is a little far-fetched I admit.

...not totally far-fetched; David Luneau has reported elsewhere that there has been talk of employing ultra-light flight craft over the Big Woods as part of the search strategies.

 

[jeeping31]

Well I new here it took awhile to read all 45 pages I hope to read more and I enjoy read the post and learn what you all know and think. See you all on the web Marcas

 

[fangsheath]

This USFWS pamphlet from 1979 has some interesting drawings of ivory-bills by George Sutton. One of the things he notes is how the longest toe is held "quite horizontal." It also has the amusing statement (not by Sutton) that ivory-bills were "very dependent" on not one but two foods - beetle grubs and magnolia fruits. This would be amazing indeed, considering magnolia was virtually non-existent, if present at all, in the Singer Tract. I do not see it on a list of 17 Singer Tract tree species from Tanner's 1986 paper. Such nonsense in an official publication provides another clear warning of the risks of appeals to authority.

http://training.fws.gov/history/Images/ivorybill.pamphlet1.jpg
http://training.fws.gov/history/Images/ivorybillpamphlet2.jpg

 

[Goatnose]

Noisy Flight

In reading Tanner, he described the Ivory Billed as having a noisy flight /quote " the loudest wing sound I have ever heard of any bird that size excepting the grouse"." I often nicknamed the birds wooden-wings/ end quote
again /quote" At times when the birds swoop past me, I heard a pronounced swishing whistle" . My question is has this subject been addressed? Did the April 2005 sighting public release mention wing sounds? In my own personnal "possible sighting" wherein I was but 30 yards away, the flight of the bird was silent. I do not wish to be skeptic here. But more I now have another diagnostic that I will incorporate in my searches other than trailing white wing tips. Got to get back out there and this time listen more ac
uetly.

 

[fangsheath]

I have seen no mention of wingbeat noises in any of the recent sightings. However, wingbeat noise is going to be highly dependent on local conditions. Cornell's own recording of wingbeat noise, which can be heard in John Fitzpatrick's plenary address, to my ear does not agree with the description "a pronounced swishing whistle." It is more like a wooden pulsing whisper, not at all loud. Yet this recording was made with a parabolic mike very close to the bird. If you are close enough hear distinctive wingbeat noise you are probably plenty close enough to pick up visual field marks.

 

[fangsheath]

Just in case you statistically-minded folks were wondering, the analysis of variance for the gouge data I posted above shows that the differences are highly significant (F = 95.7, p<0.0001). The upper limit of the 95% confidence interval for the largest pileated mean is 3.64 mm. The lower limit of the 95% confidence interval for the smallest ivory-bill mean is 4.06 mm. Of course statistical significance is not what we are really after - we are after a diagnostic tool. I believe we are getting there.

 

[Jesse Gilsdorf]

Just in case you statistically-minded folks were wondering, the analysis of variance for the gouge data I posted above shows that the differences are highly significant (F = 95.7, p<0.0001). The upper limit of the 95% confidence interval for the largest pileated mean is 3.64 mm. The lower limit of the 95% confidence interval for the smallest ivory-bill mean is 4.06 mm. Of course statistical significance is not what we are really after - we are after a diagnostic tool. I believe we are getting there.

If the tools used are not scientifically valid then they are not tools. In this instance, I assume you did the math correctly cause I know I can't, from what I remember of statistics a 95% confidence level was rather high. Given your numbers I wonder if a 98-99% confidence level would even overlap?

 

[fangsheath]

The upper limit of the 99% confidence interval for largest pileated is 3.72 mm. The lower limit of the 99% confidence interval for smallest ivory-bill is 4.00 mm. So no, there is no overlap.

 

[fangsheath]

Although it is very short on results of the Big Woods search (not surprisingly), Sam Crowe has posted fairly detailed descriptions of the search processes underway. No doubt some of the acronyms and jargon phrases will soon become standards:

COI - cavity of interest
magic hour - hour following about 3:30 P.M., when the birds are expected to head to roosts
scrape - scaled tree area suspected to be ivory-bill work

Some searchers simply take up pre-determined positions or move quietly up and down water bodies, others are conducting very systematic searches for COI's or scrapes. A VERY intensive inventory is obviously being conducted of cavities and potential feeding trees. Camera traps are clearly being heavily deployed; this should give us a much clearer idea of the kinds of scaling and excavation pileateds do in this area.

http://www.birds.cornell.edu/ivory/field/from_field_html/sc1
http://www.birds.cornell.edu/ivory/field/from_field_html/report2
http://www.birds.cornell.edu/ivory/field/from_field_html/search_tech

 

[cyberthrush]

woodpecker gouging redux

The below quote comes toward the end of another newswire article:

http://www.newswise.com/articles/view/517011/

"While the pileated woodpecker sits with its feet straight on the tree and hits the tree straight with its beak to create rows of baseball-sized holes, the Campephilus woodpecker's feet grab the tree with a wider, sideways stance, almost hugging the trunk. The woodpecker can then use its powerful bill to take lateral blows that peel away a bark layer that is fairly tight on a tree." (bold & italics added)

I can't recall if I've read of this distinction before, but if it's true that IBWOs are far more likely than PIWOs to make lateral gouges, then seems like this would be an yet another clue to look for while examining measurements of the gouges themselves.

 

[fangsheath]

I saw that article, like so many press reports it makes unattributed statements that are shaky at best. It may well be true that ivory-bills tend to have a different stance than pileateds, but I see no indication that their foraging strikes tend to be more lateral than those of pileateds, either in the literature or in field data I have seen. I suspect that the "lateral" talk is simply a reference to ivory-bills doing more bark scaling than pileateds, which do more deep excavation toward the heartwood. But I want to emphasize again that both species do both. Tanner found that ivory-bills make deep excavations about a quarter of the time, pileateds scale bark about a quarter of the time. In fact deep excavation in a certain context may be one of the our most valuable tools in finding ivory-bills. More on that later. I will say, though, that on the walls of pileated trenches I have examined, there is a tendency for gouges to curve downward as they approach the center of the tree. This may be significant - it may not.

 

[fangsheath]

Hope y'all don't think this is too hokey, just a little expression of good will to all campephiles....

The season's greetings to all from Elvis.

http://home.att.net/~fangsheath/elvismerrychristmas.jpg

 

[jeeping31]

Cool thank you about those links fangsheath I will be in and out looking at your input...and to you all have a merry christmas.

 

[fangsheath]

Okay, here's a little Christmas quiz for you. There is another large wood borer, not a beetle, that may be important in ivory-bill biology. Can anyone guess what it might be?

And I'll need that in the form of a question. (Just kidding.)

 

[MMinNY]

What is?

Okay, here's a little Christmas quiz for you. There is another large wood borer, not a beetle, that may be important in ivory-bill biology. Can anyone guess what it might be?

And I'll need that in the form of a question. (Just kidding.)

The termite? Just a guess.

 

[fangsheath]

No, although it's very possible ivory-bills do feed on termites. Allen and Kellogg found termites (and beetle larvae) in a tree that they had seen ivory-bills foraging on. Something bigger....

 

[bluedubius]

Okay, here's a little Christmas quiz for you. There is another large wood borer, not a beetle, that may be important in ivory-bill biology. Can anyone guess what it might be?

And I'll need that in the form of a question. (Just kidding.)

What is the Southern Flying Squirrel....plays hell with Red-cockaded Woodpeckers?

 

[fangsheath]

Neat choice, I love those little guys. And who knows? It may well turn out to be significant! But no, smaller....

 

[naples]

What is an ant?