Are you participating in this year’s Christmas Bird Count sponsored by the Audubon Society? Have you in the past? If so, please tell us about your experience. (The text I’m sharing here today comes from Wikipedia and from the CBC website.)
The Christmas Bird Count (CBC) is a census of birds in the Western Hemisphere, performed annually in the early Northern-hemisphere winter by volunteer birdwatchers and administered by the National Audubon Society. The purpose is to provide population data for use in science, especially conservation biology, though many people participate for recreation. The CBC is the longest-running citizen science survey in the world.
Up through the 19th century, many North Americans participated in the tradition of Christmas "side hunts", in which they competed at how many birds they could kill,[2] regardless of whether they had any use for the carcasses and of whether the birds were beneficial, beautiful, or rare. In December 1900, the U.S. ornithologist Frank Chapman, founder of Bird-Lore (which became Audubon magazine), proposed counting birds on Christmas instead of killing them.
On Christmas Day of that year, 27 observers took part in the first count in 25 places in the United States and Canada, the count totaling 18,500 individual birds belonging to 90 species.[2] Since then the counts have been held every winter, usually with increasing numbers of observers. For instance, the 101st count, in the winter of 2000–2001, involved 52,471 people in 1,823 places in 17 countries (but mostly in the U.S. and Canada). During the 113th count (winter 2012–2013), 71,531 people participated in 2,369 locations.
CBC in the Modern Era
Each November, birders interesting in participating in the CBC can sign up and join in through the Audubon website. From December 14 through January 5 each year tens of thousands of volunteers throughout the Americas brave snow, wind, or rain, and take part in the effort. Audubon and other organizations use data collected in this long-running wildlife census to assess the health of bird populations, and to help guide conservation action.
Each individual count is performed in a "count circle" with a diameter of 15 miles. At least ten volunteers, including a compiler to manage things, count in each circle. They break up into small parties and follow assigned routes, which change little from year to year, counting every bird they see. In most count circles, some people also watch feeders instead of following routes.
The results are by no means as accurate as a human census. The experience of the observing birders influences both species identification and quality of locations examined.[1] Not all the area in the count circles is covered, and not every bird along the routes is seen or identified. Big flocks can't be counted precisely. Also, telling whether a bird has been counted twice can be difficult. The rules address this problem by prohibiting counting birds when retracing one's route, except for species that the party hasn't seen before. Also, when a large roost of some species occurs in a count circle, an expert estimates the number for that species during the morning or evening and usually no individuals are counted at other times.
The data collected by observers over the past century allow Audubon researchers, conservation biologists, wildlife agencies and other interested individuals to study the long-term health and status of bird populations across North America. When combined with other surveys such as the Breeding Bird Survey, it provides a picture of how the continent's bird populations have changed in time and space over the past hundred years.
The long term perspective is vital for conservationists. It informs strategies to protect birds and their habitat, and helps identify environmental issues with implications for people as well.
What conservationists have learned through Christmas Bird Count data
- Audubon’s 2014 Climate Change Report is a comprehensive, first-of-its kind study that predicts how climate change could affect the ranges of 588 North American birds. Of the 588 North American bird species Audubon studied, more than half are likely to be in trouble. Our models indicate that 314 species will lose more than 50 percent of their current climatic range by 2080.
- The Environmental Protection Agency (EPA) has included Audubon's climate change work from CBC data as one of 26 indicators of climate change in their 2012 report.
- In 2009 CBC data were instrumental in the collaborative report by the North American Bird Conservation Initiative, U.S. Fish & Wildlife Service - State of the Birds 2009.
- In 2007, CBC data were instrumental in the development of Audubon’s Common Birds in Decline Report, which revealed that some of America's most beloved and familiar birds have taken a nosedive over the past forty years.
The Christmas Bird Count is a pretty remarkable example of the importance of what is known as “citizen science.” All you have to do is look at the staggering number of participants and data records reported to know that scientists would be hard-pressed to get this sort of data by any other method. Yay, citizens!
If you’ve participated yourself, I hope you’ll tell us about the experience. I’ve not been able to participate myself due to health reasons and that’s not going to change anytime soon. But if you haven’t done a CBC survey before, I hope you’ll be able to this year or next.
The floor is now open. What’s going on in your birdy world?