Ivory-billed woodpecker raps on
Sound tapes convince critics of the bird's survival.
Evidence has come to light that the ivory-billed woodpecker (Campephilus principalis), once thought extinct, is alive and well in Arkansas.
A sound recording of the woodpecker's distinctive call and tree rapping has convinced even some of the harshest sceptics that at least two of the birds are indeed still around.
The turn of events caps off a long-running saga. A team from Cornell University in Ithaca, New York, reported in April that they had caught an ivory-bill on video, and said that the blurred image proved the bird was not extinct1. But not everyone was convinced, and a team of three scientists had plans to publish a critical article refuting the claims, saying that the bird was instead the much more common pileated woodpecker.
But the sound tapes, which match old records from the bird's last US sightings in the 1940s and 1930s, have changed the critics' minds.
Richard Prum, a Yale University ornithologist and lead author of the planned critical article, said yesterday that the team has withdrawn their manuscript from PLoS Biology.
"The new sound recordings provide clear and convincing evidence that the ivory-billed woodpecker is not extinct," says Prum. The Cornell team handed over the tapes on 31 July, as supporting evidence to PLoS in rebuttal to the Prum team article.
Cornell officials are saying little about the tapes as they plan to report them in a scientific forum in the near future. They were not available for comment to email@example.com. But woodpeckers of the ivory-billed's genus (Campephilus) have a particular double-rapping method, which is evident on the new tape, says Prum.
Ivory-billed woodpeckers disappeared some 60 years ago as the forests of the southeast United States were cut down. The statuesque bird with its huge bill and red crest made it an international symbol of lost wildlife.
Over the ensuing decades, birders would periodically report hearing the ivory-billed's call or rap, or say they saw one. But the reports were never confirmed to the satisfaction of leading ornithologists.
After one of these reports about two years ago, the Cornell team launched an intensive search in the Big Woods region of eastern Arkansas, where wildlife refuges along the Cache and White rivers might have harboured a few ivory-billed woodpeckers.
When the Cornell team reported in Science online they had videotapes of the bird and visual sightings in the Cache River area, there was instant scepticism from some ornithologists, including Prum.
Prum and Jerome Jackson, an authority on ivory-billed woodpeckers at Florida Gulf Coast University in Fort Myers, questioned the video. Along with co-author Mark Robbins, an ornithologist at the University of Kansas at Lawrence, they said that the bird in the video was a pileated woodpecker (Dryocopus pileatus), which looks similar and often is mistaken for an ivory-billed woodpecker.
Prum says he still thinks that the video is of a pileated woodpecker. But the new tapes indicates to him that there also is a pair of ivory-billed woodpeckers somewhere in the woods.
- Fitzpatrick J., et al. Science, 308. 1460 - 1462 (2005).