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IVORY-BILLS  LiVE???!  ...

=> THE blog devoted to news and commentary on the most iconic bird in American ornithology, the Ivory-billed Woodpecker (IBWO)... and... sometimes other schtuff.
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Web ivorybills.blogspot.com

"....The truth is out there."

-- Dr. Jerome Jackson, 2002 (... & Agent Fox Mulder)

“There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.”

-- Hamlet

"All truth passes through 3 stages: First it is ridiculed. Second, it is violently opposed. Third, it is accepted as self-evident."

-- Arthur Schopenhauer






Thursday, September 29, 2005

 

-- Ivory-bills by the Numbers --

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Okay all you math geeks (and anyone else) follow me on this:

1. Let's start with a population of 16 Ivory-bills.

2. Let's say 25% of all IBWOs were killed by hunters/collectors before they could breed -- MUCH higher % than most would propose -- but this gets our starting population down to 12 immediately.

3. Let's say the average lifespan of an Ivory-bill is 10 yrs. -- at the LOW end of most estimates.

4. Let's further presume they can't breed for their first 2 years or their last 2 years -- leaving them 6 breeding years. And let's further say, for the heck of it and for reasons unknown, they routinely fail one of those years, leaving us with just 5 breeding yrs. in a lifetime for the average pair (probably way short of the truth, but whatever).

5. IBWOs were known to generally lay 3-5 eggs per nest, though often for reasons not fully understood, they only averaged raising 2 chicks.

6. So with 5 breeding years a typical pair might produce as few as 10 offspring in their entire lives. Let's say (being further conservative) that HALF of these, for whatever reasons, don't make it to adulthood. Now a pair of IBWO produces just 5 offspring in their lives.

7. We started with 16 IBWOs, reduced to 12 birds or 6 pair (for the sake of argument). These 6 pair, selecting very conservative values, could've easily produced 30 offspring in their lives (if they lived longer, bred more years, raised a higher percentage of their eggs, or got shot less, the number only goes UP!). Yet another HALF of those offspring would somehow have to fail to live/breed before you would be below replacement value for the original 16 birds. And for the species to go extinct of course you MUST repeatedly get below replacement value. I think this is difficult (not impossible) to do using reasonable guesstimates. The key of course is the IBWO's longevity and the fact that it was not often predated by anything other than Man (small songbirds that only live 3-5 years, and are easily predated or nest parasitized, can suffer extinction much more easily). Others will argue that habitat destruction caused near complete termination of IBWO breeding (in fact it's virtually the ONLY argument they can make), for if each pair merely produced 3 young in their lives they had more than (by 50%) replaced themselves. It's difficult to imagine them NOT reaching this figure in 10 years, let alone the 15-20 yrs. that most folks estimate for their longevity.
In short, given the end of hunting pressure on this bird, the increase in habitat ever since the 50s or late 40s, and every creature's normal 'will to live and breed', I think it is EASY to account for any population remaining in Tanner's time still being with us today (there is NOTHING EXTRAORDINARY about that AT ALL!). Yes, it is possible that if Tanner's low-ball estimate of 24 birds remaining in the 40's was precise the species just may have run into a "genetic bottleneck" (as some argue) that could have doomed them, but this is not inevitable, and if there were actually 50 to 200 birds left as many believe, I think the above math makes it unlikely the species could have disappeared in a mere 60 years. But hey, you do your own math...
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Wednesday, September 28, 2005

 

-- Up and Coming --

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For the last several weeks various members of the Cornell team have fanned across the country giving presentations at different groups/meetings, to mostly enthusiastic, standing-room-only crowds. An upcoming stop for some of them will be the Midwest Birding Symposium in Davenport, Iowa, Oct. 13 - 16.
This precedes the "Ecology of Large Woodpeckers" symposium to be held later in month in Brinkley, AR. (Oct. 31 - Nov. 3) just before the winter search begins in earnest.
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Sunday, September 25, 2005

 

Elvis's Mom & Dad Perhaps?...

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A bit surprised this hasn't popped up somewhere else by now: I was just re-reading parts of Jerry Jackson's book when I noticed he mentions (pg. 157) receiving a letter in 1987 from a Douglas James referencing "a report of ivory-bills in Jackson County [AR.] in 1986" that was never verified (no other details given). And looking on a state map, well lo and behold, Jackson County is home to part of the Cache River Wildlife Refuge! Gollllllleeeeee!! Do we have Elvis's parents being reported almost 20 years ago?
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Friday, September 23, 2005

 

The Iconic Ivory-bill

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In a recent letter to Science Magazine (Sept. 16, 2005, Vol. 309) anthropologist Alex Barker notes the widespread use of the Ivory-bill Woodpecker as an iconic and ceremonial item for various Native American tribes early on (including tribes outside the known range of the species). He points out one Indian pipe artifact that "used seven male ivory-bill heads as decoration," and also mentions that the bird was often rendered in prehistoric artistic depictions. Barker's point seems to be that the species may have had a far greater familiarity or commonness for early Americans than is often implied in the literature; however, I think the more important implication is just how sought-after this species was even in early America (even before the impact of loggers and habitat destruction set in). And as the bird became rarer and rarer, ironically, it was even more victimized by hunters/collectors desiring a specimen for themselves or their clients before it was gone. All of this simply reiterates my earlier notion that the impact of hunting (for food, commercial, and decorative/ceremonial purposes) on the species could be far greater than the literature acknowledges, such that law changes by the 1930s outlawing taking of the bird may have given it just the needed breathing room to stage a comeback and be with us today.
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Thursday, September 22, 2005

 

-- Gallagher Talk --

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Tim Gallagher (of the Cornell team) recently gave a talk at Cornell more-or-less summarizing his IBWO experience and book, as reported on here:

http://www.cornellsun.com/vnews/display.v/ART/2005/09/21/4330ff275ff70

(if you've read his book already, nothing really new here, but nice
summary)
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Tuesday, September 20, 2005

 

-- Weidensaul Article --

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Just discovered that this IBWO article by author-birder, rarity-chaser Scott Weidensaul from the August Smithsonian Magazine is available online at:

http://www.smithsonianmag.si.edu/smithsonian/issues05/aug05/presence.html
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Monday, September 19, 2005

 

Ivory-bills Rock!

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I just typed in "Ivory-billed Woodpecker" into a Google search engine and got 288,000 hits... hey, Ivory-bills ROCK!! (okay, so "Britney Spears" gets you 15,100,000 hits, but still...)
Anyway, yesterday, while birding along a local greenway, I chanced upon a Pileated Woodpecker foraging off the path; always a nice sight, and in this case a potent reminder to me of just how distinctive-looking this species is for any long-time birder, or for anyone accustomed to seeing them. The literature's frequent references to great similarity between Pileateds and Ivory-bills is hugely overblown and I think applies primarily to inexperienced viewers. Take a gander at any field guide showing both birds side-by-side and focus on the heads, and then on the bodies -- you will see utterly different markings (same colors, but
strikingly different patterns/appearances). It goes back to my earlier notion that the 'jizz' of these two birds differ so widely as to be wholly unlikely for one to be mistaken for the other multiple times in a row by seasoned birders... or so it seems to me.
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Saturday, September 17, 2005

 

- Being Skeptical of Those Skeptical Skeptics -

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Not much in-the-field news lately, so (tiresome as it is!) I'll again look at some of the skepticism out there.
Lately, various "professional" ornithologists' names who haven't endorsed the AR. sightings have been tossed out as further evidence for disbelieving. However, it is misleading to imply that each of these people believe there are NO Ivory-bills in AR. Some have simply taken a nuanced 'agnostic' stance that there may or may not be IBWO in the Big Woods, and the Cornell evidence doesn't reach a level of adequate proof. In fact, my guess is that if you surveyed the 1000s of ornithologists in this country dozens would say they doubt there are any IBWOs in AR., dozens would say they believe there are most likely IBWOs in AR., and the vast majority would adopt the professionally-expedient, non-committal, fence-post-straddling, uhh-well-geee-stutter-stutter-stutter view of not-quite-sure-let's-wait-and-see! Of course none of these folks saw whatever the Cornell sighters witnessed so one can question precisely how much value such a survey would even have.
Prum and Robbins are a particularly odd case: without ever seeing all of Cornell's evidence they pieced together an opposing paper (somewhat unconventionally for internet publication, but that's ok) which was significantly hyped across the web for weeks, only to then be retracted at the last minute when they heard snippets of acoustic evidence (which many of us find weak), causing them to do a 180 and suddenly deduce there were likely multiple IBWOs in AR. (a claim not even Cornell was making)! Now, supposedly, they think they may have retracted too hastily. What seems to have retracted too hastily in my opinion is their credibility!!
Most birders have never been in habitat that might be home to an Ivory-bill in their entire lives. Even so there have been dozens if not 100s of reports of the birds in the last 60 years, and no doubt many other sightings never officially turned in. (By the way, how many brief/"low quality" "sightings" of "Pileateds" over the years were actually IBWOs!!?? -- big, black-and-white woodpecker sightings are almost always routinely written off as "Pileated" despite completely inadequate looks!!) The likelihood of having a camera or video ready at the moment of a brief IBWO encounter is low, even for a dedicated IBWO searcher, let alone for the more casual observers who have made most of the sightings over the years. Indeed the vast majority of photos ever snapped of birds, especially by amateurs, are probably too poor and fuzzy for definite ID purposes (the 1000s of wonderful bird photos you see everywhere represent a tiny, tiny, tiny, tiny fraction of all photos snapped of birds). In short, there is NOTHING WHATSOEVER UNUSUAL about a rare flying creature residing in remote, poorly-accessible habitat going 60 years without a confirmed sighting/video -- why is this so difficult to comprehend!???
Regarding the Cornell evidence: 7-15+ individuals must be totally wrong in their judgments of what they saw; and while anything is possible, again how likely really that the same mistake occurred repeatedly on different days/places by different individuals with different views? Against this you have skeptics who weren't actually there (nor have seen all of Cornell's evidence/analysis) offering all manner of alternative speculative notions of what might've/could've happened. Speculative alternative explanations for occurrences are easy to come by or invent, and require evidence or proof just as much as the claims they are attempting to replace. Maybe things will eventually swing their way, but for my satisfaction the long-term reputation/credibility of the Cornell Lab/Nature Conservancy group who were on the scene trumps that of all their critics combined.
In my view David Luneau's film clearly shows a bird with too much white for a Pileated -- possibly the single best shot being the initial one of the bird edging around the side of the tree trunk prior to flight (we can go 'round and 'round on this forever). For now, I'll stick with my own notion that if that bird isn't an Ivory-bill (I think it is), then it's a mutated ibis or other heron-like species, NOT a Pileated. The acoustic evidence is, I think, weak but tantalizing. Then there are the previous claims of Mary Scott and Bob Russell. There is previous bark-scraping evidence David Luneau had seen in the White River area of AR., near the Cache River findings. Some have argued that a lot of instances of weak evidence cannot add up to strong evidence. Technically, in a strict logical sense, I agree with that, but as a matter of day-to-day practical application, I opt for "where there's smoke, there's fire." And there have been enough puffs of smoke across decades regarding the IBWO. The bottom line is that "extinction" is a HUGELY serious step -- it is imperative that we proceed with a view of the Ivory-bill as existing until proven otherwise beyond a reasonable doubt, NOT the other way around (for the last 60 years there has simply been NO EVIDENCE rising to the level of proof for Ivory-bill extinction, and yet, whether they admit it or not, this is the underlying unproven and dangerous assumption skeptics operate from.) --------------------------------------------------------------------------------------------------

Tuesday, September 13, 2005

 

- hmmm... Where To Look For Ivory-bills -

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Sometimes I tell folks, only half-tongue-in-cheek, that the best place to look for Ivory-billed Woodpeckers is not deep in bottomland forest, where the bird has ALL the advantages, and humans are stumblebums, but from a car parked on the side of the road or highway outside such woods. In 1986 John Terres, the very credible writer/birder and past Pres. of Audubon, reported having seen two Ivory-bills fly in front of his windshield while driving on a Florida highway back in 1955. He knew no good that could result from reporting it, and waited 31 years to give his account. Over the years others too have reported spotting Ivory-bills from roadways or other open-area locales, where the view was unimpeded.
If Ivory-bills are still around today, it is because juveniles and others have dispersed out of certain areas (not large enough to hold more than a few IBWOs),
with some regularity, and successfully found new suitable habitat. Dispersion offers one of the best opportunities for a good look at an IBWO, if one could only be in the right place at the right moment.
The simple point I wish to make is that sightings of Ivory-bills from highways or otherwise open areas ought to be taken and studied very seriously, and not summarily dismissed, while the frequent failure of seekers to sight Ivory-bills during forays into the swamp is to be fully expected, given a forest denizen who has likely learned that survivorship is a function of human-avoidance.
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-- Festival Upcoming --

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Looking for a weekend trip?: The "Lick Skillet Festival" in Brinkley, AR. (where last I heard, Ivory-bill haircuts and Ivory-bill burgers were available, along with the usual paraphernalia, mugs, T-shirts, etc.) will take place Sat. Sept. 24, including talks by IBWO searchers and a field trip into the Cache River area. Details below:

22nd Annual Lick Skillet Festival / Brinkley

Event Date Sat 9/24/05
Start Time 9 a.m. until
Location Brinkley Convention Center & grounds
Cost 1.00 admission
Contact 870-734-2262

Contact: sandra kemmer
E-Mail: email
Telephone: 870-734-2262

Family oriented festival. Car show, music tent with Bug Tussle Boys, Jackson & Co., arts & crafts, CASI chili cook off, Lots of children's rides, games,climbing wall, mini nascar track. The Nature Conservancy, Cornell University, Ark. Game & Fish, U.S. Fish & Wildlife, Ark. Natural Heritage, Audubon Arkansas will all have exhibits, Especially about the Ivory Billed Woodpecker and the Big Woods. At 1:30 Gene, Sparling, David Luneau and others will tell their story of the rediscovery. Dr. Dan Scheiman, Director of Bird Conservation for Audubon will lead a birding field trip at Dagmar Wildlife Management Area. There will be a bus leaving the festival grounds at 8:00 a.m. and returning at 10:00 a.m. This is free, but you must make a reservation. Call the Brinkley Chamber of Commerce to make reservations 870-734-2262. Beauty contest at 5:00 P.M. Fish Dinner at 7:00. Tickets are $10.00, aa and under $7.00 which includes play $ to spend at auction held during th eevening.

Be comfortable. If you are coming for the birding field trip, wear long pants and confortable shoes, bring insect spray and a hat, and binoculars. You can bring shorts or other clothes and change when you return from the field.



















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Sunday, September 11, 2005

 

-- Science and Sample Size --

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One of the fundamental tenets of science methodology concerns having adequate sample sizes from which to draw conclusions/generalizations. In the years since James Tanner's dissertation on the Ivory-bill (based on but a handful of birds), notions that Tanner himself often recognized as tentative became hardened into unchallenged dictums without a good basis for doing so. There is in fact little that can be stated with certainty about the Ivory-bill's diet, behavior, habits, or requirements for survival, even though such statements are rife in the literature. (If one were to intensely study a dozen people and then write a report generalizing to the entire human species the weakness would be readily apparent.) This is all especially true given that any Ivory-bills still around today may in fact have survived specifically BECAUSE they came from individuals with significantly DIFFERENT characteristics/behavioral traits from their brethren, which increased survivability for themselves and their offspring. At least Tanner got it right at the end of his original introduction:
"The chief difficulty of the study has been that of drawing conclusions from relatively few observations... My own observations of the birds have been entirely confined to a few individuals in one part of Louisiana... the conclusions drawn from them will not necessarily apply to the species as it once was nor to individuals living in other areas. The difficulty of finding the birds, even when their whereabouts was known, also limited the number of observations. Especially was this true in the non-breeding season. With these considerations in mind, one must draw conclusions carefully and with reservations." (italics added)

The problem with our knowledge of Ivory-bills is not simply how little we know, but rather how much we think we know that might just be utterly wrong for any birds remaining today...
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Saturday, September 10, 2005

 

-- Elitism... --

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John Dennis's largely excellent birding career was forever marred by his never-verified claims of Ivory-bills in Texas' Big Thicket, and premier Louisiana birder George Lowery was similarly scoffed at for his belief in La. Ivory-bills in the '70s. And through the years far lesser birding names have been derided for their Ivory-bill faith. Dennis came to believe there was a kind of elitism or "PhD-ism" involved in his treatment -- the Tanners, Allens, and others with PhDs looking down at him with his lowly Master's Degree, and not taking him seriously. Others have speculated, that at some psychological level those who witnessed the Singer Tract Ivory-bills WANTED to go to their graves with the distinction of having seen the LAST Ivory-bills on Earth, and this accounts for their sometimes knee-jerk dismissal of others' later reports.
I don't mean to debate past history here, but simply use it as a springboard to the present. If the seven names involved in Cornell's published AR. sightings had included, let's say, "David Sibley," "Kenn Kaufman," "Pete Dunne," "Paul Ehrlich," and "Clay Sutton," does anyone seriously believe the current controversy would even exist?! -- despite the brevity/quality of the sightings they would be readily accepted. But to many in the general birding community, the folks involved in the sightings are (in all due respect) relative "no-names" despite credentials. The bottom line is trust. The judgments of the aforementioned names will tend to be automatically trusted because of their "headline" status (which may or MAY NOT relate back to superior birding/observational skills), moreso than the claims of the Cornell sighters -- how many such sightings would convince skeptics -- 25, 50, 100?... or, maybe just one -- from David Sibley. This involves not so much "science" as a kind of unacknowledged "prejudice."

If the Ivory-bill's presence is verified this winter, I suspect skeptics will simply move on to the next level of argument running something like this: "well, yeah, ok... but it's just one bird out there; we ought not be spending all this time, energy, money on 1 or 2 birds, when the species can't possibly be saved." Never mind that there's close to another million-or-so acres throughout the South in need of searching. Why should cynicism cease just because a couple of birds get in the way...
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Thursday, September 08, 2005

 

-- NATURE Article --

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The latest issue of Nature magazine (Sept. 8, 2005) has a somewhat even-handed account of the controversy in AR.:

http://www.nature.com/nature/journal/v437/n7056/full/437188a.html

Apologies: sorry, this link NO LONGER seems to work except for paying customers; I used it successfully twice yesterday (for free), but either that was a fluke or heavy demand has caused the site-masters to limit access .
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Wednesday, September 07, 2005

 

- Kenn Duke & Other Thoughts -

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If you're unfamiliar with it, Kenn Duke's memory of Ivory-bills in the Pearl River region of Louisiana when he was growing up (~1970-'90), as told to Mary Scott, is just one of the many intriguing anecdotal reports around:

http://www.birdingamerica.com/Ivorybill/kennduke.htm

During a brief visit to the region in 2001 with one of Mary's groups, the Pearl River Refuge struck me as good but not great IBWO habitat (due to noise levels and general human traffic/activity), but the Bogue Chitto area just north of P.R. struck me as highly promising (Van Remsen's 2002 search team came up empty-handed at both spots). And a few hours farther north, the Three Rivers Refuge area seemed like even better IBWO habitat, though to my knowledge no thorough search has ever been attempted there. Farther west, still in La., lies the huge Atchafalaya Basin region, considered some of the very best habitat anywhere. There is no shortage of places for the serious-minded to be looking -- the haystacks are aplenty; it's the number of needles to be found that is yet to be determined.
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Tuesday, September 06, 2005

 

- Plans For IBWO Recovery -

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Read about the general plans Cornell has for 'Ivory-billed Woodpecker recovery' this coming winter here:

http://www.birds.cornell.edu/ivory/conservation/recovery

(...hey, I know what I'm hoping for for Christmas!)
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Monday, September 05, 2005

 

-- Skeptics' World --

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(...sorry, for the length)

Tom Nelson, probably the most vocal, persistent cyber-skeptic of the AR. IBWO claims has kindly cited my blog on his website, so I'll return the favor by mentioning his webpage for anyone not already familiar with it (...just puhhh-leeeze, don't embrace any of it ; - )

http://tomnelson.blogspot.com

The skeptics and I begin from fundamentally different assumptions and therefore will never agree (until of course, the definitive photo/video arises and they commence pouring heaps of salsa on their crow to make it go down better : - ))) -- Skeptics believe the IBWO is most likely extinct and has been for decades; I believe IBWOs exist in multiple locations/states and have been credibly seen (just never confirmed) many times over the years. ...From there, it just gets worse!
There isn't enough time/space to respond to every individual point cynics raise (in fact I happen to believe most skeptics are throwing up a flurry of doubts/stumbling blocks just because it is easy to do so -- one can do this on any biological subject; the number of questions raised in my view far exceeds the quality or value of those questions, but that's just my feeling). Instead, I'll just summarize a few of the broad disagreements involved:

Skeptics think all 7-15+ sightings of the AR. bird(s) were cases of mistaken identity; that the views were too fleeting to be accurate, and a kind of excited mindset may have resulted in multiple mistakes after the initial 1-2 reports.
I believe the multiple sightings from experienced and credible witnesses at different times, angles, places, of a bird of striking size and features represent excellent evidence, and the likelihood of so many mis-IDs is miniscule. (In the past, multiple-credible observers were a gold standard for a rare sighting; but suddenly in today's video-infatuated world film/photography is the new 'standard.')
Skeptics think the Luneau film is too poor and grainy to draw firm conclusions from. I believe the video is weak, and does not strongly support any one conclusion, but DOES MORE STRONGLY back the IBWO judgment than any other option (and especially so, IF one accepts the calculated measurements Cornell has made based on the video).
Skeptics think the acoustic evidence is inconclusive. I do as well, although at least some of the "kent' calls are highly intriguing.
Skeptics want a good clear photo/video of the bird; I believe that will always be difficult to attain from a possibly wary, skittish bird living deep within dense, difficult-to-access habitat
(...do the skeptics fully appreciate the size/vastness of the territory involved!?) -- getting a non-blurry photo of a bird in your own backyard on the spur of the moment can be a difficult enough task.
I believe the totality of the evidence from AR. (especially when combined with past indications for the bird's survival) strongly bolsters the existence of the IBWO in the Big Woods (...and can Florida, Louisiana, and Mississippi be far behind?)
If the believers are wrong, the worst that will happen is that money, time, resources, energy, will have been directed toward preserving a certain wild area of the Southeast on a false premise -- and, uhhh, geee... that's a bad thing??? But if the skeptics are wrong, time will have been squandered (and possibly money, energy, resources, held back) in squabbles that can't help preserve this species. For 50+ years skeptics have had their way, often scoffing at, intimidating, and denigrating those who would try to save this species, and intentionally or not, potentially nailing the coffin shut on the Ivory-bill. For once, how about we give the believers their due, give Cornell the BENEFIT-of-the-doubt (not the sting-of-the-doubt!), and for a change, give this beloved bird a wing-and-a-prayer... instead of the mere back-of-our-hand....
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Saturday, September 03, 2005

 

- Volunteer Searchers Sought -

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In case you're not already aware of it, Cornell is actively seeking volunteers with strong birding and bottomland backwoods skills (and a minimum of two available free weeks), to aid them during their winter search (Dec. - Apr.) of the AR. Big Woods area. If interested check out the details and an application at:

http://www.birds.cornell.edu/ivory/how_to_help/volunteer
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Friday, September 02, 2005

 

- A "two-fer;" interesting thought... -

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Thought this post from Dean Edwards on the Tennessee bird listserv today more than a little intriguing. (A confirmed Bachman's hasn't been seen since around 1960, but in it's heyday, the species shared the same habitat and range as the Ivory-bill):

"....you know all those autonomous recording units (ARUs) that they [Cornell] put out in the swamp to attempt to record IBWO calls and drumming. I know they're checking them for IBWO, but I wonder if anyone is checking them for Bachman's Warbler songs while they're at it? Wouldn't a "two-fer" return from the brink be nice?"


...nice inde-e-e-ed!!
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Thursday, September 01, 2005

 

-- The 'Jizz' of a Bird --

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As most readers likely know there is in birding a notion of the "jizz" of a bird -- an overall impression (gut reaction, or 'gestalt' as some would say) one gets in even a brief view of a bird -- based on fleeting features of perceived color, shape, size, and movement, in some combination. It may result in a specific ID, or simply ruling out various IDs.
Unlike many optimists, I don't find Cornell's acoustic evidence for Ivory-bills in the Big Woods compelling. And the Luneau film clip remains rightly very controversial. Upon first viewing it, the "jizz" of that bird said to me "melanistic white ibis!" -- I STILL haven't ruled that out!!! (Cornell claims the bird must be a woodpecker, because it is perched on the side of a tree at beginning of clip, BUT it is on the OPPOSITE side of the tree and thus not entirely clear whether it is grasping the tree's trunk OR perched atop a possible branch nub, though I tend to accept the Lab's analysis). Even without knowing of Cornell's calculated measurements for the bird, it appears, to my eyes, (pretty clearly) TOO large for a Pileated, but this admittedly, is subjective. Moreover, on BOTH the up and down wing strokes the bird seems to reveal far TOO MUCH white for a Pileated -- indeed, I'm amazed at those who now argue the bird could actually be a NORMAL Pileated, and need not even be leucistic!!?? In the end, one can only play probabilities, and given a hesitant acceptance of Cornell's measurement techniques/results and this bird's 'jizz,' I feel the probability is WELL over 50% for Luneau's speciman being an Ivory-bill.
BUT... the video isn't even important to me. The MOST compelling evidence, for me, remains the 7-15 sightings by experienced birders who were immediately struck by the NON-Pileated "jizz" of the bird-in-question. It's size/bulk, amount and pattern of white, and in some instances flight style, all shouted out 'something different!' -- 'like a Pileated, but NOT a Pileated!' This consensus is weighty, especially when combined with all the other evidence over decades for the bird's survival.
When David Kulivan reported 2 Ivory-bills at Pearl River in 1999, doubters clamored for multiple, or more credible, witnesses. Now, in AR. they have THAT, but once more the bar has been raised. I fear, some skeptics won't be convinced unless, as in 1932, another Mason Spencer-like figure comes forth to plop a dead, warm Ivory-bill carcass on the desk at the AR. Game and Fish Commission and declare, "hey fellas, here's that dang bird ya' all been lookin' fer." Deja vu, anyone?!
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