Patudo,
Much has happened in the last few and 8 decades.
Best to get away from the old acre to modern acre comparison as far as total acres involved. Todays forests have greatly changed for the worse in many ways; I will not cover much here. Ecological changes and fire regimes need to be paramount in understanding IBs. Also alarming is metapopulation gene flow is now minimal but can be improved. The IB is very vagile.
First up, thanks to the moderator for deleting your speculation that I'm either 'mentally ill' or an 'a-hole' and for deleting the personal attacks on others. They don't help your cause.
Second, can you stop bandying around scientific terminology in vain. There is no evidence for 'metapopulation structure' in large primary forest-dependent birds, nor is their evidence that such species are vagile, nor is there any evidence that there is any population genetic structure - i.e. 'clades' in continental Ivory-billed Woodpecker (IBWO) populations. Your use of these terms might impress some folks but you just come across as a chancer to anyone who understands the terminology.
In an attempt to deconstruct the whole story, the best available evidence for the persistence of IBWO in continental North America is:
"a de-interlaced, zoomedin, and cropped portion of a poor-quality four-second video captured fortuitously on 25 April 2004 by David Luneau, an engineering professor from Arkansas, of a bird as it flew from behind a tree and away from the camera into the woods along Bayou de View on Cache River NWR, Monroe County"
There is no other objective evidence that hasn't been widely dismissed.
So the
null hypothesis (H0) is that the Lunnea video is a normal Pileated Woodpecker (PIWO), a hypothesis favoured by many people.
The
competing hypothesis (H1) is that the Lunnea video is the sole verifiable piece of image documentation of a hitherto-thought extinct species.
For
H0 to be true we need to make no assumptions, the confusion species is common at the locality and one would expect that if you take enough bad videos then eventually one might look like an extinct species.
For H1 to be true we need a lot of assumptions:
Assumption 1. IBWO has persisted in Arkansas undocumented for around 100 years.
Assumption 2. IBWO has adapted to using a habitat type - logged and degraded forests and not the old growth forests which it was assumed to be dependent on.
Assumption 3. IBWO has changed its behaviour and ecology to become impossibly difficult to detect even with 22,000 hours searching for the bird between February 2004 and the announcement in April 2005.
On Assumption 1 and 2, this is ably deconstructed in
Jackson 2006:
There are many reasons why eastern Arkansas seems an unlikely place for Ivory-billed Woodpeckers to have survived undetected for nearly 100 years. (1) Except for small stands and individual trees, the virgin forests of eastern Arkansas were cut by the early 20th century. (2) Small stands of remaining virgin forest and second-growth forest along the lower White River were protected as White River Waterfowl Refuge in 1935, and wildlife biologists and foresters have worked in the field there ever since without any reports of Ivory-billed Woodpeckers. (3) James Tanner spent eight days on the White River Waterfowl Refuge (now NWR) in 1938 and found “no indications of the birds still being there.” He noted that “there are a few virgin tracts of sweet gum and oak timber but too small and scattered to make really good Ivory-bill territory” (Tanner 1942:25). (4) Ornithologist Brooke Meanley (1972) lived near and worked on the refuge for five years (1950-1955) and returned to the area frequently until 1970. He also visited the bottomland forests along the Cache River, noting the size of the baldcypresses (Taxodium distichum). Meanley was specifically aware of the possibility of Ivory-billed Woodpeckers in the region and was “always on the lookout” for them (Meanly 1972:52), yet he found no evidence of the birds. (5) For many decades, White River NWR has been used as a study area by researchers from several universities, resulting in numerous graduate theses and dissertations. (6) White River NWR is heavily used for hunting and fishing by the public each year. (7) By the early 1950s, birding had become popular in the mid-South, and White River NWR is frequently visited by birders and birding groups. Since 1939, there have been 48 Christmas Bird Counts centered at White River NWR. In 1994, the Arkansas Audubon Society initiated a breeding bird atlas project for the state (Arkansas Breeding Bird Survey; see Acknowledgments) that would include some of the forest habitat (K. G. Smith pers. comm.). (8) Although the forests near the mouth of the Arkansas and White rivers were prominently mentioned for their Ivory-billed Woodpeckers by John James Audubon (Audubon and Chevalier 1840-1844), the heart of Ivory-billed Woodpecker range and density seems to have been farther to the south, perhaps because of better food availability and more rapidly growing trees.
On 3, the Snyder monograph -
reviewed here might be true, maybe hunting was more important as a decline driver but it doesn't mean that the species has entirely changed its ecology - there was no evidence of this with the last few individuals in the early 20th century which were still readily located:
Are we really dealing with a species that has become reclusive and silent within the past century, as some have suggested? I do not think so. While game animals often become wary as a result of hunting pressure, I know of no evidence that suggests anything more than individual wariness as a result of negative interaction with humans. I believe that the integrity of the social system of the Ivory-billed Woodpecker, as evidenced by numerous historical reports of movement in pairs and family groups, vocal chatter, and exchange of double raps, would remain if the species has survived.
Moreover if as you state IBWO is thinly distributed across the southern USA and especially if the species were 'vagile' then we would expect to encounter dispersing juveniles away from optimal habitat, one would eventually show-up and be 'twitchable' somewhere accessible.
If you add up all the assumptions then H1 is very tenuous and hinging on a 4-second blurry video which many have dismissed out of hand as a PIWO. H0 is attractive as it requires no assumptions.