Thursday, June 14, 2007

Bird Species Show Sharp Declines in U.S.

Article by Christina Crapanzano, USA TODAY
A new study by the National Audubon Society shows that 20 common American birds, such as whippoorwills and the Rufous hummingbird, have declined by more than half in the past 40 years. "The sound of the meadowlark singing was the sound of summer; now it's not," said author and naturalist Scott Weidensaul, who joined the Audubon Society in announcing the study Thursday. Some bird species experienced more drastic declines, such as the northern bobwhite, whose population declined by 82%, and the Eastern meadowlark, which had a 71% decline.

Greg Butcher
, Audubon's bird conservation director, said the analysis indicates the impact of human behavior on bird habitats that is causing the dwindling numbers. He said key contributors are loss of grasslands and wetlands, suburban sprawl and industrialized agriculture. The study said the problem is compounded by "the escalating effects of global warming." "For the first time, we see a decline in the birds that breed in the Arctic tundra," Butcher said. He warned that some damage done to bird habitats cannot be reversed, but his goal is to "lessen the pace." "We're really pushing the limits here," he said. Carol Browner, who chairs the Audubon Society and is a former head of the Environment Protection Agency, said the bird population decline is "a problem," but added, "it's not a crisis, yet."

The study compared 550 species going back to 1967 by examining the Audubon's Christmas bird count and the U.S. Geological Survey's breeding bird count done in June. The analysis showed at least a 54% decline among 20 common bird species. Although the study focused only on birds, Butcher said similar declines could happen in other species. "One of the reasons we study birds is it shows us what's happening in other creatures," he said. "I definitely think what's happening is happening in other species as well." Weidensaul also said some bird species are overpopulated—— such as Canada goose and wild turkey. "We see more species that are in trouble than the ones that are doing really, really well," he said.

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