[7] In adults, the bill is ivory in color, hence the species' common name, and the plumage is deep black and white, with a red crest in males.

However, following public comment periods, the USFWS issued a news release stating it would continue to analyze and review information before making a final judgment.

Lovette, a member of the committee, said that more testing is needed to support that change, but concluded, "These results will likely initiate an interesting debate on how we should classify these birds.

When perched with the wings folded, birds of both sexes present a large patch of white on the lower back, roughly triangular in shape.

[34] Also, Hasbrouck's range estimate extended up the Ohio River Valley to Franklin County, Indiana, based on a record from E. T. Cox,[35] which Tanner likewise rejected as unproven or accidental.

[41] Based on reports that did not include specimens, Hasbrouck set the northern limit of the range along the Atlantic Coast to around Fort Macon, North Carolina.

[37] The ivory-billed woodpecker is not evenly distributed within its range but highly concentrated in local areas with suitable habitat and large quantities of appropriate food.

[30] Knowledge of the ecology and behavior of ivory-billed woodpeckers is mainly derived from James Tanner's study of several birds in a tract of forest along the Tensas River in the late 1930s.

[49] After the Civil War, the timber industry deforested millions of acres in the South, leaving only sparse, isolated tracts of appropriate habitat.

[51] The bird also eats significant vegetable matter, with recorded stomach contents including pecans,[52] acorns,[51] hickory nuts, poison ivy seeds, and the fruit of the southern magnolia tree.

[54] To hunt woodboring grubs, the bird uses its enormous bill to hammer, wedge, and peel the bark off dead trees to access their tunnels.

The ivory-billed woodpecker has no real competitors in hunting these grubs, as no other bird species present in its range can remove tightly bound bark in the same manner.

[55] It is also possible that nest predators of nestlings and eggs (squirrels, raccoons, and rat snakes) or fledged ivory-bills (owls and hawks) contributed to the species' decline.

[75] The National Audubon Society was among those asking the Service to reconsider, saying that while it takes no position on the validity of recent sightings, it believes a precautionary approach will help build public trust, allow time to further consider evidence, and not discourage continued surveys for the species.

[77] The Louisiana Department of Wildlife and Fisheries was among those supporting a declaration of extinction, citing a lack of conclusive evidence and a concern for the allocation of scarce resources.

[79] [80] The ivory-billed woodpecker population was devastated in the late 19th century due to heavy logging activity, compounded by bird collectors hunting them.

In 1907, one notable sighting occurred when President Theodore Roosevelt wrote of seeing three birds during a bear hunting trip in northeast Louisiana swampland.

Tanner spent 1937–1939 studying the ivory-billed woodpeckers on the Singer tract and travelling across the southern United States searching for other populations as part of his thesis work.

[87] Since 1944, regular reports have been made of ivory-billed woodpeckers being seen or heard across the southeastern United States, particularly in Louisiana, Florida, Texas, and South Carolina.

[37][88] In 1950, the Audubon Society established a wildlife sanctuary along the Chipola River after a group led by University of Florida graduate student Whitney Eastman reported a pair of ivory-billed woodpeckers with a roost hole.

[92] In 1967, ornithologist John Dennis, who had rediscovered the Cuban species in 1948,[15] reported sightings of ivory-billed woodpeckers along the Neches River in Texas during an exploration sponsored by the USFWS.

[37] At the 1971 annual meeting of the American Ornithologists' Union, Louisiana State University museum director George Lowery presented two photographs showing what appeared to be a male ivory-billed woodpecker.

[102] Although the photographs had the correct field markings for an ivory-billed woodpecker, their quality was not sufficient for other ornithologists to be confident that they did not depict a mounted specimen, and they were greeted with general skepticism.

[106] Reports of an ivory-billed woodpecker at the Cache River National Wildlife Refuge in Arkansas in 2004 resulted in a search by the Cornell Laboratory of Ornithology, led by John W. Fitzpatrick.

[117] [118] In response to the USFWS request for comments and evidence, long-time searcher Bobby Harrison submitted a 2020 video of a bird he identified in flight as an ivory-billed woodpecker.

[119] [120] In 2023 a team called Project Principalis, in partnership with the National Aviary, published trail camera photographs, sound recordings, and drone videos from a site in Louisiana, but did not claim that the evidence is definitive.

[124] For instance, bills marked with red pigment were found among grave goods in burials at Ton won Tonga, a village of the Omaha people.

For instance, Ton won Tonga was roughly 300 mi (480 km) from the farthest reported range of the ivory-billed woodpecker, yet bills were found in the graves of these people's wealthy adult men.

[10] European settlers in the United States also used ivory-billed woodpecker remains for decoration, often attaching dried heads to their shot pouches or using them as watch fobs.

[143] All vanished now from the earth—the piteous cry and all; unless where Rodney's swamps are wild enough still, perhaps it is true, the last of the ivory-billed woodpeckers still exist in the world, in this safe spot, inaccessible to man.