From the site:”The 10th-annual Great Backyard Bird count begins Friday. Amateur ornithologists are asked to count the number and species of birds they see during a three-day period and send their findings to a Web site run by the National Audubon Society and Cornell University’s Lab of Ornithology. Miyoko Chu, a science editor from the lab, tells Liane Hansen about the count.”

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TPE Link - Fundamentals of Biogeography and Ecosystems

Image: Northern Cardinal. Courtesy FWS (Source)