.comment-link {margin-left:.6em;}

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

Sunday, July 24, 2005


1. In its heyday the Ivory-billed Woodpecker resided in upland pine forests in Cuba, cypress swamps in Florida, and bottomland mixed hardwoods in Louisiana and elsewhere -- three somewhat different habitats. This was almost certainly a more adaptable species than often portrayed. For food and nesting purposes, yes, it did need relatively large, mature tracts of forest, but setting and tree-type may not have been strict limiting factors even if the bird had preferences.

2. Similarly, the few studies of Ivory-bill stomach contents available indicated that the species’ diet was about 60% vegetable matter and 40% or less animal matter and only a small percentage of the animal portion consisted of the wood-boring beetle larvae which Tanner pointed to as yet a further ‘specialization’ of this bird. In short, while Ivory-bills clearly enjoyed certain components of their diet when available, it is again less clear how necessary those components were for survival, the bird likely being more of a feeding ‘generalist’ than implied in much of the literature (indeed, no other woodpecker or bird species sharing the same habitat of the Ivory-bill appeared to have any such ‘specialized’ dietary needs, and one is left to wonder why the Ivory-bill would be different).

In short, unlike the tentative conclusions that Tanner reached which later hardened into repeated standard presumptions, the Ivory-bill may have been an adaptable species if only given enough time and solitude to do so.

3. Ivory-bills were widely hunted for food, ornamental purposes, and for both private and public collections/dis-plays (and their eggs collected as well). It is impossible to know just how many individual birds fell victim to this fate. Tanner believed hunting was second only to habitat loss in its effect on the species’ population. I believe, even at that, the overall impact of hunting may be vastly underestimated, given that Ivory-bills were never abundant to begin with, and given what relatively easy and tempting targets they would have made, always returning to the same roost or nest trees. As relatively long-lived birds (estimated 10 to 20+ year lifespan), laying 3-5 eggs per nest, Ivory-bills had ample opportunity to more than ‘replace’ themselves in their lifetimes (only two offspring reaching maturity required to replace a living pair), except when hunting cut their lives short.

4. The discovery of the species in the state of Arkansas is especially noteworthy as Arkansas was rarely high on lists of promising search locales. Florida, Mississippi, and Louisiana, were better prospects in most searchers’ minds. South Carolina and Texas were likely better as well. Georgia and Alabama remain yet other potential states for hidden Ivory-bills. But significantly, finding the Ivory-bill in Arkansas, at the northern end of its one-time range, opens the door wide to yet other little-looked-at possibilities, including southern Missouri, southern Illinois, Tennessee, and Kentucky. In short, besides Arkansas there are probably 10 or more states bearing some potential of harboring Ivory-bills. This is a bird that has had 60+ years to wander in search of food and habitat, and there is little basis for assuming it must be restrained to its former 200 year-ago range boundaries.

There is no large ‘corridor’ of dense forest left in the south for the Ivory-bill to move along as existed in the nation’s early days. Yet for Ivory-bills to still be found at all today implies that far greater numbers persisted in various locales in the 1930’s than Tanner estimated. There likely existed (both then and now) forest ‘patches’ in multiple states that were adequate to sustain one or two pair of the species, such that offspring could mature before dispersing out to seek new such patches for themselves. (Indeed one of the most intriguing facts to this writer has long been the number of scoffed-at ‘sightings’ in previous decades occurring near or over major roadways/highways, NOT in deep woods -- individual birds dispersing to new areas, perhaps???). In this way, small numbers of Ivory-bills would be ‘hop-scotching’ around the south for the last century, not just gradually inching toward some final strong-hold. With hunting and collecting pressure finally off the birds, the existence of such patches might well be sufficient to permit a population to stabilize and commence a comeback (Ivory-bills having few predators in the past other than Man). And, as Jerome Jackson has oft-noted, thanks to conservation efforts and revised forestry practices, there is literally MORE suitable (2nd and 3rd-growth) habitat available for the Ivory-bill today in the U.S. than existed decades ago at the height of forest destruction.

The ‘will to live’ and to reproduce is a persistent, potent force among living things. While the shooting of Ivory-bills essentially took individuals out of the population immediately, habitat loss, per se, had NO SUCH immediate effect for a creature that needed only to flap its wings to seek out new territory and then make new adaptations issuing from that ‘will to live.’ The genes and behaviors of any birds thusly adapting might then be passed on to a new generation, however few in number. We have, in essence, a 70-year unaccounted-for gap in our knowledge since the last known population of Ivory-bills at the Singer Tract was studied. A gap of hugely unacknowledged uncertainties.

In short, the likelihood that several dozen Ivory-bills persist in southern wilds seems to this writer FAR GREATER than the probability that humans, in our clumsiness, have stumbled upon the last 1 or 2 in existence. Based on previous distribution pattern, report history, remaining habitat, and time elapsed I would be surprised if at least half of the following states don’t harbor pockets of Ivory-bills: Florida, Georgia, Alabama, Louisiana, Missississipi, Arkansas, Texas, South Carolina, North Carolina, Tennessee, Kentucky, Missouri, Illinois, and Virginia. Actually finding the shy, elusive birds anytime soon however, is another matter entirely, for which I hold less optimism, although re-kindled interest in the species will help. ...One must even wonder if the birds may be better off UN-found. Or can we humans at long last do right by this iconic creature of the American South; this majestic and aloof phantom of the forest depths? ...Lord God, one hopes so!

(the above is adapted from material previously published in The Chapel Hill Bird Club Bulletin.)


Thanks for this site. I shall tune in regularly.

Something tells me Ivorybills are better off unfound, but if all the recent pub results in increased funding for habitat creation and protection, that will work. As noted, the forests are coming back, and the bird may well be more of a generalist than originally thought.

I feel quite sure Louisiana and probably Mississippi have some Ivorybills.

The idea of a reclusive phantom that puts in the occasional appearance appeals to me.

Long live the Lord God Bird!
I'm glad someone has mentioned what I've been saying all along. The stomach contents exams of these birds showed that they simply were not exclusively beetle larva feeders and as such, wouldn't drop out of the sky when that food source became scarce.

Also of note is that the Cuban subspecies, if it is a subspecies, lived in the hilly upland regions. Perhaps that Ivorybill I saw where there shouldn't have been one wasn't a pileated after all...
Post a Comment

Links to this post:

Create a Link

<< Home

This page is powered by Blogger. Isn't yours?

Older Posts ...Home