Recordings of the ivory-billed woodpecker’s distinctive double-rap sounds have convinced doubting researchers that the large bird once thought extinct is still living in an east Arkansas swamp.

Last month, a group of ornithologists had questioned the announcement made in April of the rediscovery of the ivory-billed woodpecker, last sighted in 1944. They said blurry videotape of a bird in flight wasn’t enough evidence. So a Cornell University researcher who was part of the team that announced the bird’s rediscovery last spring says his group sent the doubters more evidence.

”We sent them some sounds this summer from the Arkansas woods,” said John W. Fitzpatrick, director of the Cornell ornithology lab. ”We appreciate their ability to say they are now believers.”

—Ivory Bill’s Doubters Convinced by Tapes

The Cornell researchers plan to release the audio publicly at the American Ornithologists’ Union in Santa Barbara, Calif., Aug. 23-27. Explore the Cornell Ornithology Lab. More images here.