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1) The Ivory-bill Researchers Forum, where at least a few searchers, as well as other interested parties hang out, is funded for another year.
(p.s… if you had given up on it during the glitchy phase where it wasn’t loading properly for some of us, it seems to work fine now):
2) I didn’t watch the recent “Extinct or Alive” episode searching for the IBWO in Louisiana — will view it if/when it shows up on the Web/YouTube, but haven’t seen any particularly positive reviews of it from those who did view.
3) With leaves off the trees, we’re into some prime search months now, but haven’t heard anything new from “Project Principalis” in Louisiana of late:
4) If you can stomach Facebook and allowing (demonic???) Mark Zuckerberg to control your life, the long-running “Ivory-billed Woodpecker Re-discovered” group can be worth following:
Miscellaneous folks sometimes cite sightings/encounters with IBWOs, occasionally recent but more often in the distant past. Most of the claims aren’t terribly detailed or convincing or followed up on, but here’s an example of one (from E. Texas) with at least a bit more specifics from the ‘early 2000s’:
Lastly, because of some recent discussion over there I just want to stress again (talked about a lot previously) that some research argues that the Ivory-bill in early North America was likely a species of rich upland (largely pine) forests, NOT of bottomland or swamp areas. Early and rapid decimation of upland forests by white settlers may have pushed the bird into bottomland areas where it had to re-adapt while facing more competition with Pileateds, and also succumbing to hunters. In short, the long-held presumption that the species requires first-growth hardwood forest to survive may have no real basis; even possible the species was never well-adapted to bottomland swamps -- it may only require dead-and-dying trees (for food) and large living ones (for habitat)... and safety from humans.
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6 comments:
Given where the skins with good providence were obtained, and what contemporary authors (e.g., Audubon) were writing, the ivory-bill is definitely a bird of the bottomland hardwood forests. It probably also could be found in some upland pine areas, though how far is a bit unclear to me (the closest species, Cuban ivory-bills and Imperials were both more upland pines in their later years, but at least in the Cuban case, that's probably because the lowland forests were cleared first and hardest in Cuban, to grow sugar cane.)
That the Tanner map & Tanner's assessment of the habitat is used as the standard filter to decide whether a report is worth assessing is frustrating in figuring out where any significant population(s) might be found. But all the best evidence post '44 apart from sightings (which, especially by a single observer, are hard to asses) do seem to come from big river floodplains emptying into the Gulf of Mexico.
Yes, there's little doubt that by the time of Audubon and skin collectors the bird was a bottomland species, but the question is where did it reside (and indeed evolve and adapt to) for 100's if not 1000s of years prior to white settlers moving into the American South...
And as a potentially nomadic species (moving to where food, habitat, and safety were available) it's hard to know to know how meaningful the post '44 sightings are in terms of limiting where else to look and which oddball out-of-the-way sightings to take seriously (although with that said I hear from plenty of people with claims which, based on locale alone, I can't take seriously).
Where are there now extensive uneven-aged pine forests that are allowed to become overly mature? Such a place might be a good place to search, if it exists, but today’s pine plantations that are clear cut when the trees reach twenty years, are not likely to be attractive to the birds in terms of food supply.
I don't mean to dispute that it's possible ivory-bills were present, perhaps even common, in upland pine forests, but the evidence it was a species of bottomland swampy land is better. (The only source much older than Audubon I'm aware of is Catesby (1731), who doesn't specify, but does draw the bird with a willow oak branch, which is bottomlands tree - not sure if it's supposed to be indicative of anything). If one were searching, they'd be silly to exclude the latter, even if they'd perhaps be wise to give some consideration to the former.
Well, I don't think it's super-clear that the forests needed to be all that mature, either. Certainly there are records of ivory-bills feeding on fairly small trees. I would agree pine plantations are unlikely to be attractive; not necessarily because they're young, but because they're likely to have very little dead or dying timber. Going back to Snyder's argument - old growth forests may have just been tracing where there weren't a lot of European settlers, and thus the lowest hunting pressure, so the birds were doing better there. The need for old growth comes mostly from Tanner on the Singer Track, but maybe he overlooked what really made it attractive habitat - J.J. Kuhn telling hunters to get lost. If that's the case, then you'd have to start by asking where there's a lot of dying/recently dead timber - wildfires/floods/whatnot in the last couple years that've lead to beetle infestations.
The IBWO's anatomy is a clue to its niche and habitat, as are all animals and plants too. It has long, tapered wings, quite different than a PIWO's. Anatomy like this is for open-habitat flying, not woodlands, thus river corridors... and since riverine systems tend to broaden and flatten significantly in bottomlands, it shows the IBWO is adapted for bottomlands, using rivers to disperse. The ducklike aspect is for a reason, and physical adaptations take much longer to develop than the hundreds or thousands of years you are mentioning.
Most overlook that there is evidence that early Pre-Columbian Indians sought the IBWO for various reasons and probably for the entire 14,000 years man has believed to have inhabited the SE. It is entirely possible that they drove the bird mostly to the bottomlands, where it could find sanctuary, long before European settlement. It is also worthy of note that much of North Florida and South Ga. Plantations today have vast acreage of Mature Long-Leaf Pine, some may be second and third growth but large sections are virgin, and this is where Henry Stoddard had a few of his sightings near Thomasville Ga. I believe in the 50’s.
Regarding wing aspect being adapted for open-habitat flying, this also suggests the possibility that it could have easily evolved in upland area Long-Leaf pine-barrens as well, which most of the SE was Pre-Columbian. Many believe the Indians perpetuated this habitat but it could have, and probably did, occur naturally in the distant past on a large enough scale to allow evolution to do its’ thing. The IPWO has an almost identical wing aspect and there is no evidence that it ever habituated bottomlands. However, that's not to say the former wasn't true and indeed it could have been both.
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