Ivory-billed Woodpeckers, The Search Continues
by Ro Wauer
As the winter season approaches in the southern swamps, teams of birders are again preparing to head out to search for the elusive ivory-billed woodpecker. While some recent evidence from Arkansas suggests that this bird truly does still exist, some ornithologists remain skeptical. Recent evidence of its existence, that includes a few seconds of video tape and sound recordings, are not enough for some skeptics. The search for proof positive will continue.
It was February 2005 when birders, floating the Cache River in eastern Arkansas, saw what they reported as an ivory-billed woodpecker. They were so certain of what they had seen, in spite of the bird not being recorded in more than 60 years, that they convinced biologists from Cornell University and The Nature Conservancy to institute a widespread search. There followed a 13-month survey by approximately 50 people that centered on Arkansas' Mississippi Delta. That effort produced seven reported sightings, a snippet of blurred videotape, and reported hearings of the ivory-bill's nasal "kent-kent" calls and trademark double-rap drumming. But still no positive photographs.
Some skeptics suggest that all of the reports relate to smaller pileated woodpeckers rather than ivory-bills. Although these two large woodpeckers are very similar in appearance, besides the size difference that is difficult to determine at a distance, there are three principal plumage differences. First, pileated wings when perched are all black above while half the tip of ivory-bill wings are white; in flight, pileated wings are mostly all-black while those of the ivory-bill are half white. Also, pileated's facial pattern is white with a black band that runs through the eye, while the ivory-bill's facial pattern is black except for a white neck band, and bill colors are blackish-gray on pileated and ivory color on ivory-bill.
Ivory-bill’s range once extended throughout the southeastern portion of the United States, from the Texas Big Thicket area eastward to northern Florida and South Carolina. Also, there is/was a closely related ivory-bill in Cuba. Most of our knowledge of the North American bird comes from studies in the Singer Tract of northeastern Louisiana during the 1930s and 1940s. Since then, the numerous sightings have been undocumented. The exception is from the Texas Big Thicket area along Village Creek in Hardin County in 1968; tape recordings were reanalyzed following the Arkansas reports that now are considered valid. That one sure Texas record, along with a number of undocumented sightings, prompted John Arvin, ornithologist with the Gulf Coast Bird Observatory, to propose further Texas surveys of bottomland forests of the lower Trinity, Neches, and Sabine watersheds in southeastern Texas.
These and follow-up surveys in Arkansas and Mississippi over the next several months will include both aerial and ground/water searches. The 2007 season generally will extend from early January through most of April. Such a large, well-marked woodpecker can be identified from slow-flying aircraft. On the ground, teams will be combing the waterways along with viewers at lookout points that provide long stretches of streams or forest openings. Each search area contains a bewildering maze of waterways through swamp forests. Searchers must also put up with hoards of mosquitoes and an occasional cottonmouth.
The effects of Hurricane Rita for finding ivory-bills are mixed. The storm changed much of the stream flow and increased the number of logjams and tangles, making access more difficult. On the other hand, the tremendous amount of downed trees, ranging from 20% to as high as 75% in the hardest hit areas, have greatly increased the bird's food availability. Ivory-bill's principal food includes boring grubs of beetles that infest trees in their early stages of decay. And these woodpeckers create large noticeable cavities when digging for grubs.
Birders world-wide, including those who have long considered the ivory-bill extinct, are looking forward to the results of the 2007 surveys. It would be especially exciting for Texans to know that the fragments of wilderness remaining in East Texas contain some of the last strongholds of this amazing creature.