Some comments on Cornell’s aberrant Pileateds and webpage…
"The white woodpecker was first seen on February 7, 2006, by Keith Brady during a two-week volunteer assignment with the crew of Tom Snetsinger. Video documentation of the bird was obtained by Sonny Bass (also a volunteer) on February 8 and by Utami Setiorini on February 13, and stills were made by Martjan Lammertink on February 13. Upon close inspection, the woodpecker has a few small areas of darker feathers visible on the face, hind-neck, and wing coverts (see photos above and at right)."
Found, refound. Photographed, videoed, rephotographed and videoed. Many good looks, many people, definitive proof. This bird had an extremely small population (one) but there was infinitely more solid evidence produced of its existence than by all the IBWO searchers in the world in the last 6 decades. And for those who use the “huge home range” excuse, I would point out that if the IBWO has survived there must have been hundreds of individuals and hundreds of nests in the last 60 years. And nesting Ivory-Bills are loud, conspicuous, and anchored to one spot.
"Documentation of this nearly all-white Pileated Woodpecker, as well as a second Pileated Woodpecker with an unusually large amount of white on its primaries, shows that these striking birds could not have been mistaken for ivory-bills."
False. Normal Pileated woodpeckers are frequently mistaken for Ivory-Bills. Cornell briefly mistook a normal pileated for an Ivory-Bill because of reflection of sun off its secondaries. Brief sightings of Pileateds with extra white on the wings could easily be the source of the "Ivory-Bill" sightings, if the sightings were brief and incomplete, as they all were.
Also, they admit there were AT LEAST two more Pileateds with extra white on the wings. Isn’t it an amazing coincidence that this stunning "Ivory-Bill rediscovery" occurred in the area in which three or more aberrant Pileated woodpeckers have been sighted? Wouldn’t it be rational to insist on at least ONE clear photo, or the Sibley standard of "Redundancy. Repeated sightings by independent observers of birds really well seen." ? NOT ONE “Ivory-Bill” was seen well by anyone!
"The search crew easily identified the white woodpecker as a Pileated Woodpecker. It behaved and sounded like a typical Pileated Woodpecker and moved in a loose association with two normally plumaged Pileated Woodpeckers, a male and a female."
In most ways, Cornell's "Ivory-Bills" did not behave and sound like Ivory-Bills. They have not traveled in pairs, as Ivory-Bills normally do. There have been no reports of loud wing noise, which is characteristic of IBWOs. The birds were not observed while calling or drumming. Cornell's modern IBWOs are nearly impossible to observe.
"In our view, the presence of a mostly white Pileated Woodpecker in the Big Woods is immaterial to the evidence supporting the rediscovery of the ivory-bill."
Really? So why the spin page concurrent with the announcement?
And were the suppressed photos and accounts immaterial also? Despite the fact that this was a central point in the debate, Cornell didn't "come clean" until now. Have we seen all the evidence they have now, or not?
"In fact, despite persistent rumors to the contrary (Jackson 2006), we are still unaware of any photographs or specimens of a truly “piebald” Pileated Woodpecker that could potentially be confused with an ivory-bill. A possible exception is a bird observed and described by Noel Snyder in Florida."
A POSSIBLE exception??? "Had the bird flown on immediately after I detected it, I would have been forever sure that I had seen a living Ivory-bill." And how about the Fred Collins birds? “In the 70s there was a partially albino Pileated Woodpecker that was very much patterned like an Ivorybill. It required a visit. Already since the Arkansas sighting another bird like this has been reported in Baytown. Fortunately with the use of Internet birdcalls, this Baytown bird was identified as a Pileated without a trip to the home. These birds demonstrate that plumage alone will not assure you that you are tracking an Ivorybill. Calls are not a sure bet either.”
In their original paper Cornell said this: "We are unaware of any examples of extensively and symmetrically pibald pileated woodpeckers in museum collections or the literature." They didn't investigate alternate explanations very well, because apparently they didn't know about Noel Snyder's bird. And if Collins is correct, the Texas bird in the 70s and the one from 2005. And that's just the ones "in literature."
And if you need photographs or specimens to prove a bird exists, Cornell is in big trouble.
"Fitzpatrick et al. (2005) argued that if such an aberrant Pileated Woodpecker was present there, it should be seen and re-found without difficulty."
Real birds can be found and photographed, imaginary birds can't. So far they have photographed at least three aberrant Pileateds.
"any leucistic Pileated Woodpecker present in the vicinity of our ivory-bill sightings and video in spring 2004 would be regularly seen and heard in the same area, as this area has been intensively monitored almost continuously since March 2004. "
So where are the IBWOs?
"What I did state to several individuals is that I made three separate sightings on different days of a Pileated Woodpecker that had an abnormal amount of white on the dorsal part of the wing when folded in the Bayou de View study area. I do not know if this was one woodpecker that I just happened to observe three times or three different birds. Given the number of Pileated Woodpeckers (typically 10-20 per search day) I saw at Bayou de View last year, it seems unlikely it was the same bird."
So one person saw at least one, and probably two or three aberrant Pileateds.
Question, if he had so many of these sightings, how about all the other dozens of people on the Cornell team? They said Pileateds were so easy to see and document, right? So several other searchers saw Ivory-Bills but not these aberrant Pileateds? What’s the explanation? Could it be the other people did catch brief glimpses of these birds?
"In short, despite our concerted efforts to find any, we have no evidence of leucistic Pileated Woodpeckers in this region of the Big Woods."
Just the one white one and who knows how many other aberrant Pileateds.
"Reports of other odd-plumaged Pileated Woodpeckers with “extra white” in the Cache/White River study area have persisted since our announcement of the rediscovery in April 2005."
The reason that they persisted is because they were true. If the Cornell Lab of Ornithology wants to claim scientific objectivity, they should have laid all the relevant facts on the table from the beginning, and let other scientists decide for themselves what the facts show.
Friday, February 24, 2006
Comments on Cornell's abnormal Pileated page
An anonymous source emailed me the following:
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16 comments:
This person's comment is so biased it omits the key reasoning given to show why Noel Snyder's observation is not applicable in the Big Woods.
"...A possible exception is a bird observed and described by Noel Snyder in Florida that had cream-colored white triangles on its wings...However, Snyder notes that the bird lacked the large white bill characteristic of the ivory-bill (Snyder 2004)."
See! The bird lacked the large white bill. Uh oh! So have all descriptions of reported Ivory-bills in Arkansas in the past two years.
When you see a large woodpecker for 2-3 seconds with the sun hitting the secondaries it is clearly an IBWO. When you see that same bird for more than 3 seconds, it becomes a PIWO.
;-)
P.S. Check out Birdforum sometime. They are yin to your yang. I've never seen a group of people so quick to believe every crackpot sighting/call that comes along.
Just becaue the bird forum people don't say "yer a damn crackpot" doesn't mean we believe. Maybe we're just POLITE?
"When you see a large woodpecker for 2-3 seconds with the sun hitting the secondaries it is clearly an IBWO. When you see that same bird for more than 3 seconds, it becomes a PIWO."
When I see comments like this I sometimes wonder if these people have ever even been birding.
As far as needing hundreds of IBWOs and nests to have made it 62 years into the present. Not really proven.
Also the idea that inbreeding
would destroy the bird... also not
really proven, in fact it was breeding in the 30s in the Singer
Tract and holding its numbers until 1941. New offspring were
being born, about 1/2 had nesting failures but Tanner concluded that
the nesting success rate until the tract started to be cleared, was
about as good as a Song Sparrow.
But of course, IBWO's laid 2-4 eggs and a Pileated 3-5, and a song sparrow 4-6.
And presumably the bird was already
pretty darned inbred. What may have been happening is that nesting attempts drop off as the bird got pressured from all sides.
But oddly enough, even in the 30s,
a pair managed to raise 4 young to young adulthood successfully twice (can't tell if it was the same pair from the book).
Now getting back to Elvis.
Cornell will try to say "Elvis has left the room now". The skeptics will say... that's just a guy in an Elvis suit who can't even sing!
Cornell counters... "that's not an Elvis suit, we also saw a guy with a long white coat." The skeptics fire back: "You never saw Elvis' face!" It's a bit hard to judge all this. And in this case, the
bird never died, it merely vanished.
Paul Sutera - New Paltz, NY
Most experts think that the smallest viable population would be 20-30 birds. If that's the smallest estimate, a minimum average of 10 breeding pairs a year seems reasonable, so that would mean about 600+ nests since Tanner's day.
To me, the "long shot" is not finding a nest, but that someone never stumbled across a nest and realized its significance. It doesn't take an organized search to find Ivory-Bills, as was once often proven.
"When I see comments like this I sometimes wonder if these people have ever even been birding. "
sarcasm....ever hear of it?
Been birding for 21 years. Proud to be a lister, proud to have seen over 650 species. Proud to do yearly Christmas bird counts, proud to build nest boxes for species that need them, proud of my 15 year career in conservation related activities.
Now, my point was...the only observations Cornell has documented were of the < 10 second duration, and most were < 5 seconds. People are making quick calls about white secondaries with only a fleeting glimpse. There have been 100s of Pileated sightings in AR, these are more than fleeting glimpses. Get my point?
When birding I look at EVERY Pileated I see and I manage to see the head
> 80% of the time. While is this so hard to do for IBWO sightings?
"When birding I look at EVERY Pileated I see and I manage to see the head
> 80% of the time. While is this so hard to do for IBWO sightings?"
Recent scientific studies suggest that Pileateds and Ivorybills are in fact two different species, and may exhibit different behavior.
A couple of points:
1) Why do Cornell say this "however, Snyder notes that the bird lacked the large white bill characteristic of the ivory-bill", because on no occasion has the Cornell team seen the bill well enough to note this feature.
2) Sorry Paul, but I would disagree with your discussion on inbreeding. I don't think it would be possible to say conclusively that inbreeding was a factor behind the decline, but the reasons Paul gives for inbreeding not having had an effect are incorrect. Inbreeding can produce small effects, that may take several years, decades even, to be significant.
3)On Luneau's site he says "in 20,000 or so person-hours of searching, there have been around 15 sightings that lasted an average of maybe 3 seconds each".
Does anyone know of any other bird species on earth, that is only viewable for an average of 3 seconds, and also apparently only in flight?
If the answer in no, than all these sightings are surely Pileated, whether aberrant of not.
Large numbers of seabirds
Wood ducks in forested swamps are usually seen flying. Sure, where they are abundant, you will see them perched and swimming. But this is not the norm, less than 1 in 15 birds in forested areas.
Accipiters in closed forest are usually seen as a "flash" for an instant, only occasionally found perched (less than one in 15 times)
Cuckoos are the very devil to spot in the woods, they are usually seen on the wing, and briefly.
Most of the band-tailed pigeons I see are on the wing, in the woods, moving fast. Not all, but over 90% I'd wager.
Woodcock are seldom seen except flying over or away rapidly, other than during their courtship flights.
Do I need to continue?
Yes, please continue, because most of what you wrote is just plain wrong.
Just for the heck of it, I'll address your first point about seabirds: It would have to be a pretty fast seabird to disappear from sight in three seconds on the open water.
The ABA typically will not add a new species (or a "rediscovered" species") of seabird for the ABA area without a clear photograph showing all of the identifiable field marks. That standard has been met for many pelagic species over the years, but has yet to be met by any person claiming to have recently seen an IBWO.
And for what its worth, another recently "rediscovered" species of seabird, the NZ storm-petrel, has somehow managed to be regularly refound and photographed (and even examined in-hand) a number of times since that species was "rediscovered. Where is that sort of proof for the IBWO?
Would you like me to continue?
P.S. Recent studies have also shown that although Ivory-billed and Pileated Woodpeckers have different behaviors, they both have HEADS.
Yes please do continue, I'd like to hear about the wood ducks and sharpies that sit still for good looks in the woods every time you spot one.
Oh, and, I wasn't addressing whether 15 brief looks constitute acceptable evidence for reinstating a species on the ABA list, though that is what you responded to. I was addressing whether it is reasonable that 15 looks at a rapidly-flying forest bird could likely all be brief and on the wing. Nor did I address the relative ease/difficulty of photographing a bird flying by in the woods versus over open water.
So, sharp-shins in deep woods are NOT normally seen briefly and on the wing?
Why don't you respond on the seabird point first? Of course you can't, because what you said just isn't true.
Please identify for me the large number of seabirds that are only seen for three seconds and are only seen in flight.
I guess I'll answer two of your other questions: Yes, I do often get good looks at Wood Ducks and Sharpies. You know, some birders *are* capable of seeing birds before they flush them. You ought to try it some time.
A point I missed out on inbreeding, is that it can have effects on survival, and thus could lead to a population decline without a change, say, in clutch size.
There is no seabird or any of the other examples given that are ONLY seen for 3 seconds, otherwise there wouldn't be photos of them.
Has anyone else seen whats going on on birdforum?
They have managed to convince themselves that a woodpecker which doesn't have a white trailing edge or show the right amount of white in the wing, when perched, is an Ivory-bill. Amazing.
Upon reading Cornell's article about these "Newly" discovered abnormal Pileated's is puts the evidence being presented in favor of the Ivorybill to be less conclusive. The white on the wings seems not to be a totally tell tail marker only to Ivorybill's as first presented. We now have proof positive this is also found in other birds in the area in question. Now, it totally rest on size, wing beat & wing shape.
The article states there was video, along with stills, made of these birds talked about & shown on the page. One now has to wonder what this video shows. Does these birds show a completely differant flight pattern than the video used to validate the Ivorybill? How would this video stand up if it was to be presented using the same standard used to validate the discovery?
That is something yet to be determined. But, it would be something I think needs to be done.
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