America's birds more at risk than ever.

• Position: Global Warming

Global warming threatens nearly half the bird species in the continental U.S. and Canada, insists a study by the National Audubon Society, New York, which identifies 126 species that will lose more than 50% of their current ranges--in some cases up to 100%--by 2050, with no possibility of moving elsewhere if global warming continues on its current trajectory. A further 188 species face more than 50% range loss by 2080, but may be able to make up some of this loss if they are able to colonize new areas. These 314 species include many not previously considered at risk. The report indicates that numerous extinctions are likely if global temperature increases are not stopped.

"It's a punch in the gut. The greatest threat our birds face today is global warming. That's our unequivocal conclusion after seven years of painstakingly careful and thorough research," says Gary Langham, Audubon's chief scientist. "Global warming threatens the basic fabric of life on which birds--and the rest of us--depend, and we have to act quickly and decisively if we are going to avoid catastrophe for them and for us."

Birds that could lose all of their current range by 2080 include the American avocet, brown rosy-finch, brown-headed nuthatch, chestnut-collared longspur, eared grebe, northern gannet, northern saw-whet owl, trumpeter swan, white-headed woodpecker, and yellow rail.

"The prospect of such staggering loss is horrific, but we can build a bridge to the future for America's birds," notes David Yarnold, Audubon president and CEO. 'This report is a road map, and it's telling us two big things: we have to preserve and protect the places birds live, and we have to work together to reduce the severity of global warming."

Langham and other Audubon ornithologists analyzed 30 years of North American climate data and tens of thousands of historical bird observations from the Audubon Christmas Bird Count and U.S...