I almost certainly ignored this article when it came out.

Have spent the afternoon doing a bit of tidying up, which includes recycling my enormous collection of fire hazards in the loft, including lots of old Birdwatch magazines. The May 2001 issue (here)


carried an essay by James Tanner called ' A Forest Alive', which I have never seen in full before. Here's some quotes, again which I've never seen in full

Winter is the best time to hunt for Ivory-bills. The birds were quite active and called frequently; their calls carried far through the leafless forest, and the same bareness made it easier to see and follow them. Every day of this season was used in hunting, trying to follow and count the birds before spring made it harder and also necessary to concentrate on nesting studies. Steady pursuit of the woodpeckers did not mean that eyes and ears were closed·to other birds and animals; instead, we were often led right among them. One December morning I started out well before daylight and walked through the dark woods to the roost tree of an Ivory-bill. Barred Owls were hooting ~ from here and there, and three of them flew from the tree-tops, hooting as they went, near the Ivory-bill's roost. By then, 6.30, there was a dim grey light in the woods. I knew there was plenty of time, so settled myself comfortably on a dry hummock. Brown Thrashers were just beginning to call. Soon White­-throated Sparrows and a Winter Wren sang, a squir­rel 'mewed' and a Carolina Wren called. At 6.45 the thrashers were very noisy, calling a hoarse, vigorous charr that welled up from the undergrowth. The sky in the east glowed rosy-pink, when suddenly and mysteriously the thrashers quietened. Three Wood Ducks flew over and then slanted down, twisting their way through the branches to land nearby in the water. Several loud plunks puzzled me, until I found that they were caused by large acorns falling into the still water. Two squirrels, one black and one grey, were creeping out along the twigs of a tall oak after the acorns, knocking many loose. When a squirrel suc­ceeded in securing an acorn, it crawled back with its gain to some comfortable limb to eat. The next bird to call was a White-breasted Nuthatch. At seven o'clock came the whining cry of a Yellow-bellied Sapsucker, the early riser among the winter woodpeckers, but not really early as by then the woods were quite light. Soon after that, a Red-bellied Woodpecker called and others answered immediately. One Red-belly flew to the top of the dead stub in which the Ivory-billed Woodpecker roosted, and drummed on the top. Almost at once a female Ivory-bill slipped quietly from her roost hole and jerked her way to the top of the stub, where she rapped and called a few times. Then she flew to another tree and settled to preen herself, interrupting her toilet occasionally with a call or a sharp pound on the limb. Another Ivory-bill answered from a short distance north and then flew to join the first; it was another female, but judging from its appearance a bird of the year. The two sleek black and white birds called and pounded a few times and then flew off together to begin feeding. I followed them on this day for three quarters of an hour as they moved from one tree to another until they finally took a long flight beyond my sight and I was not able to find them again.

also

Spring was the busy season for hunting and following the Ivory-billed Woodpeckers. They are like most birds in being active and noisy in the early morning: consequently we did most of our searching then. The usual routine was to be up an hour before daylight, cook and wolf a quick breakfast, and be on the trail as soon as it was light enough to see the way.

As other have pointed out... you can only rationalise the failure of the current searches if you don't include the words 'active and noisy', 'called frequently' and 'easier to see and follow', in your dataset.