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Cathy Wurzer

St. Paul, Minn.

September 21, 2007 6:40 AM

Global warming may affect bird migration

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A Swainson's thrush, common in northern Minnesota. These birds migrate to southern Mexico and as far south as Argentina in the fall.
Photo copyright Roland Jordahl

Fall is migration season for thousands of of bird species. Some bird experts say that global warming is changing the migration patterns of those birds.

MPR's Cathy Wurzer talks with migratory bird expert Scott Weidensaul, author of "Of a Feather: A brief History of American Birding," about this phenomenon.

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