The ivory-billed woodpecker (Campephilus principalis)is one of the rarest birds in the world and is considered by most authorities to be extinct in the United States. The last confirmed sighting of ivory-bills was in Cuba in 1987 or 1988. Though never common, the ivory-billed woodpecker was rarely seen in the United States after the first years of the twentieth century. Some were seen in Louisiana in 1942, and since then, occasional sightings have been unverified. Interest in the bird rekindled in 1999, when a student at Louisiana State University claimed to have seen a pair of ivory-billed woodpeckers in a wilderness preserve. Teams of scientists searched the area for two years. No ivory-billed woodpecker was sighted, though some evidence made it plausible the bird was in the vicinity. By mid-2002, the ivory-billed woodpecker's return from the brink of extinction remained a tantalizing possibility, but not an established fact.

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