I've been doing some detailed research on Ivory-billed Woodpecker (IBWO) habitat requirements. In my opinion, it seems that the current habitat in southeast Arkansas is sub-optimal for the IBWO, and it may take ~90 years for more ideal habitat to develop. Please read through the material below and see if you agree...
1. Here's what the late Jim Tanner wrote in "The Ivory-billed Woodpecker", pages 87 and 88:
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...Ivory-bills feed mainly upon the kinds of borers (larvae of Buprestid and Cerambycid beetles) that bore or mine between the bark and sapwood of dead limbs and trees. These larvae are present for only a comparatively short time. They are the first to appear in a tree or limb that has died, usually about a year after death; they are commonest under the bark of wood that has been dead about two years, and then they quickly disappear. Because of its short existence in one place, the food of Ivory-bills is relatively scarce and very irregularly distributed in the forest. An Ivory-bill can find food only in some dead trees or parts of trees, and once these have passed a certain stage of decay, the Ivory-bill can no longer secure food there.
Other kinds of woodpeckers eat borers that mine deep in the decaying sapwood and heartwood of dead trees for from two to ten years after the death of the wood, a much longer period. Therefore, their food is much more common and widespread, and they can live in many kinds of forests. On the other hand, Ivory-bills must live where numbers of trees are constantly dying, so that they can find enough trees or limbs with borers beneath the bark.
Logging the virgin forests removes most of the large, old trees which, indirectly, supply food to woodpeckers. Young trees spring up to take the empty places; but young trees grow rapidly, are healthy, and usually contain little dead wood. For woodpeckers they are not much good. Second-growth forests support far fewer woodpeckers than do primeval forests; for example, in the virgin timber of the Singer Tract, Louisiana, the population of Pileated Woodpeckers was from three to six pairs per square mile, but in the neighboring second growth there was less than one pair per square mile. Even in the warm swamps a tree will grow for about 150 years before it is 'old', so it would take many years of uninterrupted growth for a forest once logged to become again ideal habitat for woodpeckers. In the meantime, these birds would greatly decrease or disappear.
Because of their food habits, Ivory-billed Woodpeckers are more endangered by the cutting of old trees than are other species of woodpeckers. Other kinds can find food in trees in all stages of decay, so their food is much more widespread, and they are able to live in many places where Ivory-bills cannot. Ivory-bills, on the other hand, can find enough food only in places where dead and dying trees are common, which is usually only in old, virgin forests.
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2. Cornell's paper says this about the potential IBWO habitat in Arkansas:
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The present Big Woods landscape consists of patches of mature forest amidst a matrix of regenerating trees of various ages; its resource base for ivory-billed woodpeckers is much reduced compared to that of the Singer Tract...
The Big Woods (fig. S6)—at 220,000 ha, the second-largest contiguous area of bottomland forest in the Mississippi River basin—includes 20 distinct types of swamp and bottomland hardwood forests (16). About 40% of the forest is currently approaching maturity (oldest trees >60 years). The remainder, while younger (20 to 60 years), is growing rapidly. An additional 40,000 ha of adjacent or nearby land has been reforested in the last decade and is in early successional stages. If a few breeding pairs do exist, most of the conditions believed to be required for successful breeding and population growth (5) are becoming more available to them. Strategic additions to the public refuge system and successful restoration efforts by both public and private landowners are reestablishing mature hardwood forest, the crucial foraging habitat for ivory-billed woodpeckers (5). Increasing the extent and diversity of genuinely mature bottomland forest with large, very old trees and substantial standing dead and dying timber may allow future generations to see the awe-inspiring woodpecker again gracing old-growth treetops.
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I would agree that conditions are getting better, but it is a very slow process. The fact that the young trees are growing rapidly is not very helpful--those healthy trees would not be a good food source for Ivory-bills. It looks like many decades need to pass before the current crop of trees will get old enough and decrepit enough to provide good IBWO habitat.
3. Jerome Jackson seemed unimpressed by the potential Ivory-bill habitat in Arkansas. He wrote this about southeast Arkansas on page 158 of "In Search of the Ivory-billed Woodpecker":
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Superficial examination of habitats revealed few areas of extensive, mature bottomland hardwoods, and I discontinued my efforts in the state.
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4. This article by John Fitzpatrick was published in 2002:
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...Whether or not the bird still exists (odds are strongly against it), the ivory-billed story demands our full attention as a vivid symbol of the most comprehensive conservation failure of 20th-century America. By 1900, millions of acres of virgin pine and hardwood still existed in the southeastern United States. Who could have predicted that in our individual, corporate, and public lusts for materials and revenue, we would lack the foresight or collective will to save even a single tract of this primary forest? Quite simply, we cut it all.
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5. Now we have this scene.
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Mike Melnechuk with The Nature Conservancy, uses a lance-like tool to inject a chemical into a tupelo tree, causing it to die, in hopes of creating a more hospitable habitat for the rare ivory-billed woodpecker, Thursday, Aug. 4, 2005, in Benson Creek, near Brinkley, Ark. Scientists are betting that the soon-to-be rotting ash, locust, red maple and tupelo trees will attract the longhorn beetle, the larvae of which are the woodpecker's most favored food.
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Personally, I don't think it's prudent to go off and start killing healthy trees for the IBWO at this point. For one thing, I think it would be a good idea to hold off at least until we have some good photos proving that any IBWOs still survive. After all, if we believe they are alive today, we must also believe they survived and successfully nested for the last 61 years without anyone killing trees on their behalf. Also, of course, any 60-year-old trees we chemically kill today are not going to be part of a potential 'old' forest 90 years from now.
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And of course, an underlying question is: If the Ivory-bill does exist today, what the heck is it doing in Arkansas, rather than Florida, Louisiana, Mississippi, South Carolina, Georgia, or Texas? On page 246 of his book, Jerome Jackson ranks all those latter states as more likely places than Arkansas for Ivory-bills.
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