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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.

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

Wednesday, September 10, 2014


-- I Get Emails (...plus IBWO Speculation) --


(1935 Arthur A. Allen, Singer Tract)

Several seabirds spend almost their entire lives far out at sea. Chimney Swifts spend a remarkable percentage of their lives in the air, coasting on the wing. Even warbler species have fairly specific physical niches they inhabit and don't depart from much… some rarely encountered more than 20 feet off the ground, others rarely found lower than 40 feet high. All bird species adapt to fit niches, sometimes narrow ones...

A couple of weeks ago someone sent me a picture of bark scaling, they thought interesting, at the base of a large tree trunk. I don't think there's any chance it's Ivory-bill work, but I'll get back to that in a moment.
Over the course of this blog people have occasionally sent me pics and audiofiles they find interesting of things encountered in their outings.
Unfortunately, in 9 years, hardly a single photo, kent sound, or double-knock sent my way has looked/sounded very promising to me. Double-knocks are hard to judge (and highly ambiguous), especially on often scratchy or muffled recordings so I can't rule out IBWOs on many of them… but I also can't rule out a multitude of other sound-alike alternatives. "Kent" sounds that people have sent along rarely sound like IBWO to me (sometimes I can't even tell why the sender finds it interesting); I can only remember one, or perhaps two, such recordings sent in that really made my ears prick up quite a bit (I've forgotten now if that was from Arkansas or Florida); and, in any event, again there are a LOT of ambiguous, kent-like sounds possible in the woods. Nor has any photo of a bird sent my way been cause for excitement. Lastly, folks send photos of cavities and foraging sign -- again, none very compelling (though some more interesting than others).  I don't want to discourage people from sending such things along (...I'd rather view 100 worthless pics, than risk missing out on the one photo that actually 'rings my chimes'), but I do want folks to realize that the chance of getting a positive response from me is incredibly slim, especially if you yourself can't determine what you have -- but if you do send something, please include as much additional information/details as you can that might add any significant context to the attachment that I'm viewing/hearing.

Anyway, back to the more recent (bark-scaling) photo… basically I don't believe that any current-day IBWO would forage low on a tree trunk for any significant amount of time -- depending on the nature of such scaling, there are numerous other possible critters from deer, bear, beaver, squirrels, wild boar, humans, that might cause such damage.
I'm in the camp that believes any remaining IBWOs have evolved heightened wariness and caution, and as such DO NOT spend ANY extensive time at ground level, where they would be far more vulnerable. In fact, I believe they are now almost exclusively residents of the upper canopies, other than when flying from point A to point B and requiring a clear pathway. While they might land momentarily lower on a tree, they probably spend most of their daily lives minimally 35+ ft. high up (maybe 50+ ft.) on tree trunks/branches and inside cavities, well above levels frequented by Pileateds and other woodpecker cousins (and generally out of easy sight-line for searchers). It's not clear to me how many of the remote automatic camera traps were ever set that high (though it's clear several were not). Like Swifts in the air and Albatrosses at sea, I think Ivory-bills may spend most of their lives solely in the canopies… if you send me a photo of foraging sign or a cavity or a fuzzy bird lower than ~35 ft. high, I probably won't take it too seriously (even though there are historical records of such cases), unless there are overriding additional details to catch my attention. If Ivory-bills currently lived and foraged below 35 ft. to any significant extent I believe we'd have the definitive evidence we need by now (well before now!); only perhaps as a denizen of the upper reaches might they be able to carry on successfully, while also evading encounters and detection to the degree they have.

I recall a veteran birder once imploring other birders (who missed interesting birds flying overhead), "always look up (...unless you're driving down the road!)" ...perhaps, just perhaps, in the case of the Ivory-bill no truer words apply.

Your exclusion of any work below 35' is arbitrary and wrongheaded, IMO. Forget Allen and Kellogg, Tanner even observed that they're "not averse" to coming near the ground. Do you really think such a significant behavioral change evolved post-Tanner? An animal seeking food is going to go where the food is, and as it happens, the largest quantity of food is often to be found in the boles. I agree that cavities will be high up and also that work that's exclusively near the base of the tree is suspect, but when the work goes higher than about 10 feet you can pretty well rule out a mammalian source (unless giraffes are around or there's some heretofore undiscovered porcupine species in the swamps of Louisiana and Florida). When it's very extensive, you can be pretty confident that it's either PIWO or IBWO, and as I've argued at length on the Project Coyote blog, I think there is a limited range of work that is identifiable as IBWO.
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