Frequently Asked Questions - CBC

The Christmas Bird Count (CBC) is a long-standing program of the National Audubon Society, with over 100 years of citizen science involvement. It is an early-winter bird census, where thousands of volunteers across the US, Canada and many countries in the Western Hemisphere, go out over a 24 hour period to count birds.

The first CBC was done on Christmas Day of 1900 as an alternative activity to an event called the "side hunt" where people chose sides, then went out and shot as many birds as they could. The group that came in with the largest number of dead birds won the event. Frank Chapman, a famed ornithologist at the American Museum of Natural History and the editor of Bird-Lore (which became the publication of the National Association of Audubon Societies when that organization formed in 1905) recognized that declining bird populations could not withstand wanton over-hunting, and proposed to count birds on Christmas Day rather than shoot them.

Count volunteers follow specified routes through a designated 15-mile (24-km) diameter circle, counting every bird they see or hear all day. It's not just a species tally--all birds are counted all day, giving an indication of the total number of birds in the circle that day. If observers live within a CBC circle, they may arrange in advance to count the birds at their feeders and submit those data to their compiler. All individual CBC's are conducted in the period from December 14 to January 5 (inclusive dates) each season, and each count is conducted in one calendar day.

All individual CBC's are conducted in the period from December 14 to January 5 (inclusive dates) each season, and each count is conducted in one calendar day.

Beginning in late fall of each year, you can visit the Christmas Bird Count Get Involved web page to search for a circle near you. Circles will be listed with upcoming count dates as compilers enter them. Please check back if you do not see a count date listed for your circle of interest.

No, as of the 113th CBC, from December 14, 2012 to January 5, 2013 there is no required fee to participate. We welcome donations to support the CBC program. Please consider donating by clicking on the "Donate to the CBC!" menu item on the right-hand side of the page.

Absolutely. The data collected by observers over the past century allow researchers, conservation biologists, and interested individuals to study the long-term health and status of bird populations across North America. In the 1980's CBC data were used to document the decline of wintering populations of the American Black Duck, after which conservation measures were put into effect to reduce hunting pressure on this species. See more about how the CBC data have been used recently in Audubon's Birds & Climate Change and Common Birds in Decline reports.

As long as you live within a designated CBC circle, you are welcome to count the birds at your feeder. All you'll need to do is contact your local Compiler in advance of the count day to arrange to participate. Then you may report your results on the Count Day. Please contac the Compiler before the CBC period, which is 14 December through 5 January every season, by selecting "Get Involved" from the CBC home page.

CBC participants are organized into groups--or field parties--by the organizer or Compiler of each Count. Each field party covers a specific area of the 15-mile diameter circle on a specific route. And anyone is welcome to participate, since Compilers arrange field parties so that inexperienced observers are always out with seasoned CBC veterans.

No. Since each CBC is a real census, and since the 15-mile diameter circle contains a lot of area to be covered, single-observer counts (except in unusual circumstances) cannot be allowed. To participate on the CBC you will need to join an existing CBC circle. To do so please contact the compiler in advance of the count day by visiting our CBC Get Involved web page.

As an alternative, you may be interested in getting involved in the Great Backyard Bird Count (GBBC) organized by Audubon with the Cornell Lab of Ornithology. It takes place President's Day weekend each February and you can count the birds each day in your backyard/community and then enter the results online. For more information on the GBBC, visit: http://audubon.org/programs/great-backyard-bird-count

No. Since each CBC is a real census, and since the 15-mile diameter circle contains a lot of area to be covered, single-observer counts (except in unusual circumstances) cannot be allowed. To join a CBC circle please contact the compiler in advance of the count day by visiting our CBC Get Involved web page.

To sign up to participate in a CBC circle, first check the list of circles and upcoming dates available on the Get Involved page. This list will become available in late fall of each year. Instructions on how to sign up will be available when the circle search tool goes live.

Accepting online registrations of participants is the individual decision of each circle Compiler and is based on a number of factors including the number of participants already committed to the count, the amount of area already covered and the compiler's available time.

We have created a 24 minute video presentation that covers the history of the Christmas Bird Count and explains how the CBC data is used.  You can view the video presentation here: http://birds.audubon.org/videos/audubons-christmas-bird-count-tallying-birds-americas-over-century

The Christmas Bird Count pressroom can be found here: http://www.audubon.org/newsroom/press-rooms/christmas-bird-count-press-room