The Audubon Christmas Bird Count (CBC) is the longest-running standardized bird census in North America. It was begun on Christmas Day, 1900, by Frank Chapman, curator of the American Museum of Natural History in New York City and an early officer in the fledgling Audubon Society. He conceived the idea to count birds on Christmas Day as an alternative to the tradition of a one-day “side-hunt” where gunners competed to see who could shoot the most birds. Remarkably, even in that first year counts were conducted from California to Toronto and New York.
From that humble beginning (25 counts with a total of 90 species recorded), the 117th count (2015-2016) included 2,536 counts from Canada, the U.S., Latin America, the Caribbean and Pacific Islands. And the impressive scope of last year’s counts goes beyond the just the geography covered; nearly 75,000 observers participated, tallying nearly 60 million individuals of more than 2,600 bird species!
For many, the CBC is more than a bird survey. It represents a holiday season tradition, a chance to spend time outdoors with friends and family, away from the crowds and commercialism. Spanning the advent of the new year, for many it offers a chance to “top off” their year list, or to kick off a new one. Many observers cover the same areas year after year, and come to have a deeper understanding of early winter bird populations in their area.
Of course, collecting data in a standardized way over multiple decades also allows us to see changes in bird communities and distribution across many scales. CBC data reveal irregular “irruptions” of northern species such as Snowy Owls, Pine Grosbeaks, redpolls, crossbills and Bohemian Waxwings. They also reveal the steady movement of many southern species northward over time, including Northern Mockingbird, Carolina Wren, and Mourning Doves; the rapid spread of Eurasian Collared-Doves across the continent from east to west; and the long-term decline of Evening Grosbeak populations.
For more on the history of the CBC, see: https://www.audubon.org/history-christmas-bird-count
For detailed results of the 117th CBC, see: