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安魂曲
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作者：安魂曲 在 罕见奇谈 发贴, 来自 http://www.hjclub.org
Ivory-billed woodpecker not extinct
Scientists report sightings of bird in Arkansas, release video
Thursday, April 28, 2005 Posted: 10:55 PM EDT (0255 GMT)
This illustration shows the endangered woodpecker. Its wingspan is about 3 feet wide.
WASHINGTON (CNN) -- An ivory-billed woodpecker -- widely believed to be extinct and whose last confirmed sighting was 60 years ago -- is alive in Arkansas, according to a research paper released Thursday.
And there are plans to use federal money to preserve the bird's habitat.
Evidence the woodpecker still exists includes eight independent sightings between 2004 and 2005 and a videotape.
"The bird captured on video is clearly an ivory-billed woodpecker. Amazingly, America may have another chance to protect the future of this spectacular bird and the awesome forests in which it lives," said a statement from John Fitzpatrick, director of the Cornell Laboratory of Ornithology, The Associated Press reported.
Fitzpatrick co-wrote a paper about the discovery that was released Thursday in the online version of Science magazine.
Interior Secretary Gale Norton called the find an "exciting opportunity," the AP reported.
"Second chances to save wildlife once thought to be extinct are rare .. we will take advantage of this opportunity," she said at a news conference.
The AP reported that Norton and Agriculture Secretary Mikle Johanns promised federal assistance to protect the ivory-bill.
The paper's authors said that observers heard drumming sounds that are consistent with those made by the bird.
Searchers have been unable to spot the bird outside a three-kilometer area of the Big Woods region of Arkansas, but the paper's authors note the area is prime to support a few breeding pairs.
As a result of the sightings, the Cornell Lab of Ornithology, the Nature Conservancy and other groups have joined to form the Big Woods Conservation Partnership to conserve 200,000 acres of forest habitat and rivers in the area during the next 10 years.
The last confirmed U.S. sighting of the the bird was in a Louisiana hardwood forest in the 1940s. The bird is second in size to the endangered imperial woodpecker of Mexico, once the largest woodpecker on Earth.
Ivory-billed woodpeckers have a nearly 3-foot wingspan and are almost 20 inches long -- about the size of an American black crow.
They once spread across bottomland hardwoods and mountain pine forests of the southeastern United States and Cuba.
The birds, which require a large area for feeding, maintained a small, healthy community until the late 1800s.
Logging and hunting caused the birds' severe decline to near-extinction, according to the Cornell Lab of Ornithology.
The birds lived primarily in mature deciduous forest swamps in the southeastern United States, Cornell Lab's Web site states. It takes about three square miles of mature forest to sustain a breeding pair of ivory-bills.
By 1938, about 22 birds remained.
But reported sightings -- in Florida, Texas, Mississippi and Louisiana -- spawned searches. Many of those sightings turned out to be of the more common, slightly smaller and more widespread pileated woodpecker.
The ivory-bill differs from the pileated in size, bill color, the female's all-black crest and large patches of white on the lower back of the perched bird. When perched, the pileated appears solid black on the back.
In 1999, a Louisiana State University student David Kullivan said he saw a pair of ivory-billed woodpeckers in a remote bayou.
"That morning, I was sitting at the base of a tree," Kullivan told Audubon magazine. "Suddenly, these two birds were in the trees. I watched them for 15 minutes.
"The male -- the bird with a red crest -- seemed to be doing all the calling. I was awfully excited when they flew away. I tried to follow them, but they were gone."
Cornell and Zeiss Optics sponsored a search of the area beginning in 2002, but they did not find any clear evidence of the bird.
Mary Scott, avid birder and operator of the Web site BirdingAmerica.com, says she saw the ivory-bill in Arkansas in 2003, but did not announce it until April 27, 2005. Scott said she saw the bird while taking a break and without her camera.
Gene Sparling reported seeing the bird while he was kayaking in early 2004 in the Cache River National Wildlife Refuge in Monroe County, Arkansas.
Bobby Harrison of Oakwood College in Huntsville, Alabama, and Tim Gallagher of Cornell, who was writing a book about the bird, asked Sparling to lead them to the site where he saw it.
Two weeks after Sparling's sighting, Gallagher and Harrison saw the bird, too.
Five more sightings -- all by experienced observers -- came between April 5, 2004, and February 15, 2005.
But the key evidence is an April 25, 2004, video that David Luneau shot. It shows a large woodpecker perched on a tree and flying away as his canoe approaches.
"Its images are blurred and pixilated owing to rapid motion, slow shutter speed, video interlacing artifacts, and the bird's distance beyond the video camera's focal plane," the paper says of the video.
"Despite these imperfections, crucial fieldmarks are evident both on the original and on deinterlaced and magnified video fields."
作者：安魂曲 在 罕见奇谈 发贴, 来自 http://www.hjclub.org |
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