...Even a glance of a partially obscured sign or very distant sign can allow you to recognize familiar product logos. Your brain has a tremendous power to filter out distractions and fill in details of familiar patterns, and patterns in birds are no exception.In the case of "Ivory-bill" sightings, I think an observer might conceivably get a fleeting glimpse of a bird that apparently shows "too much white" on only one upperwing, and then "fill in the details" so that extra white on both upperwings might be later remembered. The partial cue of apparent extra white on the upperwing could also influence the observer to unconsciously fill in other "extra" details beyond what was actually seen--maybe impression of overall size, flight style, bill length, etc.
That said, there is a danger in filling in details in this way. You can jump to conclusions and convince yourself that certain desired details were actually seen...
I think this example provides one illustration of the power of the human mind to use partial cues:
Here, take heart. I love re-reading this as I too am a bad speller.
Believe it or not, you can read it.
I cdnuolt blveiee taht I cluod aulaclty uesdnatnrd waht I was rdgnieg.
The phaonmneal pweor of the hmuan mnid. Aoccdrnig to rscheearch, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoatnt tihng is taht the frist and lsat ltteer be in the rghit pclae. The rset can be a taotl mses and you can sitll raed it wouthit a porbelm.
Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.
Amzanig huh?
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16 comments:
Amazing indeed. A bit of a stretch to fill in a few white feathers with a broad white back. Unless our bird is like the pileated discovered in Florida with a lot more white; The Fla bird turned yellow perhaps by its association with pine sap around the nest hole.
Now on your issue of no photos.
Incredibly another species almost extinct by 1900 and generally considered extinct was sighted in 1962 and photographed before the days of photoshop! Despite its predeliction for prairies, sandflats on migration, etc, this bird existed but was never photographed for many many decades after its near extinction. And there was another sight-only record from the late '80s.
http://members.tripod.com/~tbrc/eskimo.html
So it isn't impossible for an extant bird to escape the photographer's lens for many decades, even if it still exists in small numbers.
You could argue that there have been no universities nor million dollars spent nor many books written for this beautiful bird, the Eskimo Curlew. And I have to say, right you are and they may still be extinct today (most think so).
But it does show that a very rare bird can escape decades of being photographed even though it could turn up in a flock of shorebirds and be more easily seen than an IBW. It looks like a Whimbrel. I guess we'd have to question this photograph too, but it's a generally accepted photo.
Of course the IBW may well be as gone as the Curlew seems to be today, despite this one perhaps very lucky photo. The Curlew was thought extinct by 1900 and these photos are only 1 of three sightings that were accepted in the 20th Century.
So we're talking mighty rare here!
More info on the Curlew can be found here:
http://texasbirding.net/birds/eskimo.htm
Sorry to hijack the forum for a different species. I still want a photo half that good for a bird that
has the whole birding community in
its virtual crosshairs!
Paul - New Paltz, NY
Remember, we're not talking about a single abnormal Pileated in the search area; Cornell has admitted seeing several individuals, presumably with different abnormalities.
More information is
here
I think this post makes an extremely important point.
People need to remember that these sightings included thousands and thousands of brief glimpses of Pileateds. Not possibly, for sure. And these brief glimpses included aberrant Pileateds with extra white on the wings. Not possibly, for sure. It's a recipe for excited minds to "fill in the blanks" and believe, truthfully, that they've seen an Ivory-bill when they haven't.
A quote from the archives (Remember, these are the words of Cornell): http://tomnelson.blogspot.com/2005_12_01_tomnelson_archive.html
LOOK –- LOOK! Flying across the levy right in front was a large woodpecker. The sun was at our back so this could be the right time and the right place –- a large flash of white moved the blood-pressure up a notch –- then the bird morphed into the very common pileated. The shiny black feathers had reflected in the sun, and just for moment, there appeared to be white on the trailing edge of the wings. A slight change in the viewing angle and it was clear the white was not what it had seemed.
They saw white on the trailing edges, even when it wasn't there AT ALL. How many times did that happen in the countless Pileated sightings?
Eventually people will realize that these types of mistakes explain why Cornell got several brief glimpses but could never get ANY good looks or photos or videos of their Ivory-bill(s.) With a good look the bird would always, every time, "morph into the very common pileated."
I agree it's troubling, especially the seeming tendency for black colored birds to exhibit some albinism (it's higher in crows, for example). And Pileated's can have a bad molt, I suppose ... witness the Turkey Vultures flying overhead on ragged wings w/missing feathers.
I think the 'jizz' people are neck and neck with the albinistic/leuco-winged groupthink-pandemonium theory in my primitive brain, at least.
Yet a few talk of the hugeness of the bird (I don't have links)...
I'd hate to think so many people could go hog-crazy (another Bigfoot, Hogzilla!) and be hornswaggled by
pattern fill but it could happen.
Now how about that Curlew photo, Tom? One good photo in 100 years.
Sorta shoots the "60 years, no real evidence, they gone!" theory in the foot.
It happened for the Curlew, it may have happened for a mammal in Vietnam.
Paul Sutera - New Paltz, NY.
Now how about that Curlew photo, Tom? One good photo in 100 years.
Sorta shoots the "60 years, no real evidence, they gone!" theory in the foot.
I'll take a shot at answering that point.
Firstly, no one is saying that the lack of a photo in 62 years is PROOF, in itself, that the Ivory-Bill is extinct. As a matter of fact, I don't know anyone who is saying that there is a totality of evidence that PROVES the bird is extinct.
I think what Tom and others are saying is that the lack of solid evidence of any kind over a 60+ year period raises the burden of proof to a very high level, a level that no one, including Cornell, has come close to yet.
I think potential US observers of the Eskimo Curlew were significantly hindered by the fact that the birds bred above the Arctic Circle and spent the northern winter as far south as Patagonia (quite possibly not setting foot in the US during fall migration).
In addition to the several good photos of two birds that you reference, a specimen was collected in 1963, and it looks like specimens were also collected earlier in the century.
No one knows for sure if the Eskimo Curlew is extinct, but an Audubon web page says the bird "has not been reliably sighted for 30-40 years."
Yes the burden of proof is higher with no photo. But I've read "and of course, no photo" many times
from many authors, including myself!
The tone implies "You'll never get it." or a haughy: "There you go again, wild-eyed loon-believers".
The Curlew nests in NW Canada in the Mackenzie area. And it lingers a long time on migration on the shores and prairies before laying eggs way up near the Arctic. Much like the Blackpoll warbler and with the same fall migration path usually minus the SE coast but including the New England coastline. If they didn't spend a lot of time in the temperate zone, how would they have gotten decimated by hunters? They spend significant time in this country waiting for the average temperature in their breeding area to go up. The fact that they migrate means they are MORE likely to be seen, NOT less likely. And certainly their
affinity for Wide-Open spaces helps too. Not to mention how many more birders are out in Spring migration
The 30-40 years refers to the Texas photos, but prior to that the specimens go way way back.
I can't find a 1920s-onward report of any EC specimen. 1965 had a specimen in the Bahamas.
Ok that's 2 birds. It does show
we need to stop indignantly stating:
"Of course, no photo", "Of course, only a blurry photo".
"Of course, no dead birds, no feathers, no nest holes".
"Of course only inconclusive bark peeling". But yeah I too get grumpy about how excited people get about hearing a Kent-like call or seeing bark-peeling. Then these hyper-believers feel skeptics are out to ruin their fun!
Paul Sutera, New Paltz, NY
And of course, no irrefutable proof of ANY kind. Regardless of odds or arguments, that's what's needed to prove the fact.
You don't need to be a whacko to believe in the Ivory-Bill, but you do need solid evidence to turn your belief into a fact.
"Reality is that which, when
you stop believing it, doesn’t go away."
I completely disagree that a tiny remnant population of Eskimo Curlews would be more likely to be photographed than a similar population of U.S. Ivory-bills. To me, it seems that the Ivory-bill would far be easier to photograph, living in the country year-round and being variously described as "sedentary", "very, very conspicuous", and "half-tame".
In the 1930s, we evidently did have small remnant populations of both species. Note that we have a lot of good Ivory-bill photos from the 1930s, but evidently no photos of Eskimo Curlews from that decade.
Hi Tom,
Well the counter-argument goes there were far more birders in the NE and on shores of Texas (Galveston Island) than there were birders in the difficult swamps of the south. How birders many on the Texas coastal areas doing spring fallout, for example? You probably haven't birded often in places where every bush has more birders than birds.
IBWs: Yes loud, yes conspicuous.
In your world, the southern swamps are too small and busy to hide a small remnant population of noisy birds during the nesting season.
One expert on southern swamps
says you underestimate the vastness of the south to make the "hard to miss it" point.
Perhaps you will at some point workout an acres/transects/sounds
grid... based on the 8 percent number. Then do the matrix algebra to figure out how much area currently still lacks "ear" coverage. Based on the 1/2 mile that an IBW's voice travels.
For now, I'll go with the southern swamp expert over somewhat ad-hoc estimations of "vast-or-not?"
I believe strongly too these suckers are pretty raucous. Good job debunking that theory!
Paul Sutera, New Paltz, NY
Please note that Laura Erickson (not exactly a raging skeptic), is currently in Arkansas and seems to be having difficulty finding vast, untrammeled swamps.
Laura wrote:
"...wilderness this is not, by any stretch of the imagination. I can hear cars and airplanes from our campsite, to say nothing of gunfire, and there is a disturbing amount of trash--from beer and pop cans to toilet paper--in the woods. If the Ivory-billed Woodpecker depended on genuinely untrammeled wild habitat, we didn't leave it much at all."
Please note that Laura Erickson (not exactly a raging skeptic), is currently in Arkansas and seems to be having difficulty finding vast, untrammeled swamps.
Laura wrote:
"...wilderness this is not, by any stretch of the imagination. I can hear cars and airplanes from our campsite, to say nothing of gunfire, and there is a disturbing amount of trash--from beer and pop cans to toilet paper--in the woods. If the Ivory-billed Woodpecker depended on genuinely untrammeled wild habitat, we didn't leave it much at all."
Untrammeled? I guess not, but that does not mean it's not vast.
Ummmmmm...my "world" IS the South, and my "underestimation of the vastness of the South" is awfully big talk for someone hailing from...New York. I live, drive & walk all over it, especially Georgia, Tennessee, Alabama & Florida. Much of my driving has been in coastal plains area in s. Ga. and Ala. I've paddled through the Okefenokee several times as well as the blackwater rivers in n. Fla. I've also visited several times in the delta areas of Mississippi. While I"m not a credentialed "expert on southern swamps", I'd say that I've got a "better than the average bear" idea of how big is the South.
Here's the thing: I'm not sure that I have to defend the assertion that IBWOs couldn't have "hidden in plain view" in a pocket SOMEWHERE in the south. You'll never logically prove a negative assertion. Maybe there is a relict population in some little bayou. I wish they were. But - if I follow your reasoning - what the Cornell "amen pew" has to substantiate is, based upon evidence in hand, how IBWOs supposedly hid in plain sight in ONE very small pocket that was heavily frequented by observers. I think the "transect" discussion is irrelevant. That NWR ain't that big in the first place. IBWOs were supposed to be big, noisy and move around. Are we now arguing that IBWOs managed to maintain a viable population not only limited to a tiny little NWR, but hemmed in even more tightly to just the area out of earshot of the human travel routes in the NWR? These birds would have NEVER passed by an observer?
These birds would have NEVER passed by an observer?
They could have passed by many observers, but it wouldn't matter much if that observer didn't have a video camera pointed at it. Otherwise, I'm sure everyone would think that observer only saw a Pileated, albeit poorly.
Well it's depressing to hear these IBWs are living in little bogs next to mini-malls, miniature golf courses and interstate onramps. I've heard knowledgeable people tell me both things. That the swamps are vast, or that they are hemmed in on all sides. And that the South has nothing like what NY State has.
Now the Adirondacks are pretty darn vast. Even in the Catskills I drove a country road for 30 minutes and saw one other car. On Slide Mtn, the singing of Bicknell's Thrush, though loud, quickly gets lost of the underbrush. I doubt many would be up to the 3 hour steep hike, just to hear this bird. No-one else in my bird club ever made it up to the
4150 feet elevation.
That's why I'm also dubious of people's ability to go 3 miles into a difficult swamp. I can't apply my Northern woods experiences to the southern swamps. But the physical limitations of most flabby Americans allows me to be skeptical of the image of birders traipsing all across the easy footing of these swamps.
Though I'm open to what people are saying about the Southern swamp forest.
Paul Sutera, New Paltz, NY
Having spent a lot of time in wilderness areas, including southern swamps, I can tell you that there's virtually no place you can get away from people for very long. Sure, there are places where access is much more difficult. But hunters, especially, seek these hard-to-reach areas. Many hunters are birders and many birders hunters.
Also, judging by what I'm seeing online, enthusiastic birders are heading into good ivory-bill habitat all across the south.
If Ivory-bills exist, proof should have been found by now. If they exist proof WILL be found.
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