The annual Christmas Bird Count kicked off on Dec 14. As a citizen science movement, the CBC has a long legacy of more than 100 years.

The bird count undertaken by the National Audubon Society attracts thousands of volunteers across the United States, Canada, and other countries in the West.

The early-winter bird census excites volunteers as they go out over a 24-hour period on a particular day to count birds.

The bird census starts in each November, when potential birders for CBC sign up through the Audubon website. Between the scheduled dates of Dec. 14 and Jan. 5 every year thousands of volunteers hit the bird trail and brave snow, rain and wind to exert themselves for the census.

CBC Plan For 2016

The 117th edition of the Christmas Bird Count of Audubon started on Wednesday, Dec. 14 and will run through Thursday, Jan. 5, 2017. The activity relies on the dedication and commitment of volunteers, who are free to participate in as many counts as possible.

This year a map view of the circles has been included to help birders find a count near their location. There is no online registration for the 117th CBC and interested volunteers would need to coordinate with circle compilers directly by email using the information from the map.

The count usually takes place in a 15-mile-wide diameter circle organized by a count compiler. The volunteers have to count every bird seen and heard all day. Since the CBC is not a species tally, it requires counting birds throughout the day to indicate the total number of birds in a circle.

According to Audubon, being a real census within a particular diameter circle, the CBC requires covering a lot of areas. Therefore, single-observer counts will not be allowed.

Bird Hunt Turns Into Bird Count

What is interesting is that prior to the Christmas Bird Count, there used to be Christmas "side hunts." The original tradition had gun-wielding hunters racing to kill birds during Christmas season to win the best hunter's prize.

However, mounting concern from observers and scientists over the falling numbers of the bird population made the ritual turn into a different exercise geared toward conservation.

Frank M. Chapman, an ornithologist and officer of the newly formed Audubon Society was the man behind the new tradition. He proposed counting birds beginning on Christmas Day in 1900, and the Christmas Bird Count was established.

The first census had Chapman and 27 dedicated birders counting birds in Toronto in Ontario, Pacific Grove in California, and the population centers of northeastern North America. The original Bird Counters compiled data on 90 species.

Valuable Bird Data

Data from this census is used by Audubon and others to decide on conservation action. The century-long data has been a good tool for Audubon researchers and wildlife agencies to study bird populations across North America.

When combined with surveys like the Breeding Bird Survey, the CBC provides a window to the continent's changing trends in bird populations over the past hundred years.

The Environmental Protection Agency even included CBC data as one of the 26 indicators of climate change in its 2012 report.