PENSACOLA, Fla. – After spending months in remote northwest Florida swamps searching for the ivory-billed woodpecker, researchers say they have seen and heard the rare bird once believed to be extinct.
But Auburn University ornithologists, who published their findings in Canada's Avian Conservation and Ecology journal online Tuesday, failed to capture a picture of the large woodpecker, which makes a distinct double rapping sound.
That lack of evidence means doubt about the bird's return remains.
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The bird was thought to be extinct until 2004 when Cornell University researchers released recordings and an inconclusive grainy video after searching for it in the swamps of eastern Arkansas. The last confirmed ivory-billed sighting was in 1944.
Auburn ornithologist Geoffrey Hill headed the four-month Florida search that ended in April.
He said his team would return to the Choctawhatchee River basin sometime around November with better equipment to try to get photographs.
"On 41 occasions different team members have seen the bird. We heard that double knock, it's a sound the ivory-billed makes that no other bird makes, but we didn't get a clear video of the bird," Hill said.
"I think people should be skeptical. I think they should demand clear photographic evidence. I might start to get skeptical myself thinking, 'I've seen this bird,' but how could I have seen a bird that it is impossible to photograph," he said.
The Florida Fish and Wildlife Conservation Commission is working with the federal government and some private agencies to provide additional funding for Hill's team, agency spokesman Willie Puz said.
Puz said funding is in the early stages and he didn't know how much the researchers would receive.
Hill's five-member team from Auburn, Ala., conducted its search on a $10,000 budget. Hill said the extra funding should help them deliver the conclusive evidence the world is demanding.
"The ultimate prize is finding pairs visiting roost holes and making babies, that would be the holy grail," said John Fitzpatrick, director of the Cornell lab, which consulted with the Auburn team. "Absent that, the intervening step is to get a photograph that allows everyone else to see the evidence and get on board."
Florida officials praised the early evidence.
"This will be fantastic if we can confirm the woodpeckers are there," conservation commission Chairman Rodney Barreto said in a statement. "Florida is the only state besides Arkansas to come close to confirmation in roughly 40 years."