The ivory-billed woodpecker recently went from near total obscurity to superstardom when birders reported a sighting of the believed-to-be-extinct species.

The world's third largest woodpecker was condemned to oblivion some 50 years ago, but in April 2005, a stunning video emerged from a vast Arkansas swamp forest. The tape appeared to show a live ivory-billed woodpecker—and captured the attention of the world. It was hailed as the birding equivalent of finding Elvis alive.

In the wake of the discovery, some experts supported the evidence while others suggested that the tape showed a similar, smaller woodpecker—the pileated—which remains common in much of North America.

Ivory-billed woodpeckers make a unique double-knock noise when pecking at trees, and this sound may be a crucial aid