Common Birds in Decline: How Citizen Science Revealed the Problem

Citizen Science view2

Citizen Scientists participating in the Christmas Bird Count.

For the first time ever, this analysis combined data from the world's longest-running uninterrupted bird census -- Audubon's Christmas Bird Count (CBC) -- with information from the Breeding Bird Survey (BBS) to study how populations of all common North American species routinely encountered in these surveys have fared during the past 40 years. The CBC data are the product of swarms of volunteers --citizen scientists-- who counted birds every winter over this period and submitted their reports to Audubon. The BBS is a standardized morning count of birds along roadsides organized by the U.S. Geological Survey and conducted by volunteers from May into July.