A case of mistaken identity for the Ivory-billed Woodpecker?

March 15, 2007

An artist´s image of what an ivory-billed woodpecker looks like. Credit: George M. Sutton/Cornell Lab of Ornithology

Video evidence that an extinct woodpecker is alive and well in Arkansas, USA may prove to be a case of mistaken identity. Research published today in the open access journal BMC Biology shows how fleeting images thought to be the Ivory-billed Woodpecker Campephilus principalis could be another native woodpecker species.

J. Martin Collinson compared David Luneau's Arkansas video footage from April 2004 of the supposed Ivory-billed Woodpecker with fresh footage of the Pileated Woodpecker Dryocopus pileatus, a superficially similar black and white species. The Pileated Woodpecker's wings were thought to beat more slowly that the 8.6 beats per second captured on Luneau's video, and its wings have black trailing edges. The trailing edges of the Ivory-billed Woodpecker's wings are white.

Aberdeen-based Collinson concludes that Luneau's video shows a bird that is not fully identified, and probably a Pileated Woodpecker. His analysis of the fresh Pileated Woodpecker video footage showed that its wings did reach 8.6 beats per second during an escape flight.

He also found that as Pileated Woodpeckers fly away from the camera, their plumage is hard to distinguish from the Ivory-billed Woodpecker's. He suggests that the Pileated Woodpecker's distinctive black trailing wing edges can be spotted in the Luneau video as the wings stroke downwards. Previous analysis suggested these were the black wingtips of the Ivory-billed Woodpecker.

Collinson argues that the Ivory-billed Woodpecker's rediscovery remains unproven: "With no verified reports in the USA for over 50 years, it seemed impossible that a crow-sized black, white and red bird should have eluded the nation's ornithologists, hunters and conservationists in heavily populated South-eastern USA for so long."

However, the original video published in Science catalysed conservation efforts in SE USA's bottomland swamp forests, which face continuing development. Furthermore, it spurred renewed efforts, in Florida and elsewhere, to find the Ivory-billed Woodpecker and determine its status in the USA.

Source: BioMed Central