After analyzing more than 18,000 hours of recordings from the swampy forests of eastern Arkansas, researchers at the Cornell Laboratory of Ornithology at Cornell University have released recordings offering further evidence --

including the legendary bird's distinctive double knock -- for the existence of the ivory-billed woodpecker, once thought extinct. These sounds were recorded in the same area of Arkansas where the species was rediscovered in 2004.

The Cornell researchers announced the results at the annual meeting of the American Ornithologists' Union in Santa Barbara, Calif., Aug. 24, and they have invited the public to listen to the calls and knocks on the Web at www.birds.cornell.edu.