What I did that day might seem insignificant in the grand scheme of protecting our global environment. In fact, I believe it represents the one thing that will save our planet—individual action. The Christmas Bird Count is the longest continual wildlife-monitoring program in the world. I did my part that day, just like thousands of other volunteers had done every year for a century. My small contribution became important to science and conservation because of the collective power of individual action sustained year after year. —National Audubon Society President John Flicker recalling his first Christmas Bird Count
The National Audubon Society’s Christmas Bird Count (CBC) is the oldest and largest citizen science event in the world. This winter bird survey has been held every year since 1900—110 years. The first Christmas Bird Count was held on Christmas Day 1900 as an alternative to the holiday side hunt tradition, in which teams went out to shoot as many birds as they could. The team with the biggest haul “won.” Famed ornithologist Frank Chapman realized that wild bird populations could not long withstand such events and proposed counting birds on Christmas Day instead of shooting them. Chapman organized two trial counts in 1899, one in Princeton, N.J., and one in New York City’s Central Park. In 1900, the Christmas Bird Count tradition officially began when 27 people participated in 25 Christmas Bird Counts across the United States.
During this event, volunteers from across the western hemisphere spend a day identifying and counting birds. All Christmas Bird Counts are held during the same three-week period every year, Dec. 14 to Jan. 5; birds can be counted from midnight to midnight on the count day. Christmas Bird counters cover the area in a defined 15-mile (24-kilometer) diameter circle, identifying and counting every bird they see or hear. This provides an estimate of the total number of birds and the species of birds found in that area on that day. Field counters are assigned to cover specific areas of the circle in an attempt to cover as much of the circle as possible. Feeder watchers count the birds at their backyard feeders or in their neighborhood.
The information provided by present-day Christmas Bird counts is important for conservation. These bird population data are the most comprehensive available for mid-December to early January for the western hemisphere. When they are combined with other studies, such as the North American Summer Breeding Bird Survey, we get a picture of how bird populations have changed over time. These programs allow all of us to participate in the development of strategies to protect our birds and their habitat.
Last year, there were 2,124 counts held, ranging from Prudhoe Bay, Alaska, to Cape Crozier, Antarctica. A total of nearly 66 million (65,596,663 to be exact) birds were counted by 59,813 observers. There were 361 counts in Canada, 1,673 in the United States and 90 in Latin America, the Caribbean, the Pacific Islands and beyond. The 2,126 species identified represent a bit more than one-fifth of the world’s estimated total of 10,000 species of birds. Last year, 10 Christmas Counts took place in Nebraska. Lincoln counters saw 63 different species, Omaha counters reported 60 species and Lake McConaughy counters saw the most with the state high of 97 species.
Recently, ornithologists Paul Johnsgard and Tom Shane analyzed 40 years of Christmas Bird Count data. They summarized their findings in the monograph “Four Decades of Christmas Bird Counts in the Great Plains: Ornithological Evidence of a Changing Climate.” The monograph is available online through the University of Nebraska’s Digital Commons. Their analyses, and those of many others, indicate a general northern shift in the winter ranges of many bird species, which is attributable to global warming. If winters continue to warm and this northern range shift continues, overwintering habitat and food supplies may not be able to maintain our bird populations.
Curious about how the Lincoln, Neb., Christmas Bird counts have changed over the years, we went to the National Audubon Society Christmas Bird Count public access database. Using this resource, we summarized the history of the Lincoln count from 1998 to 2008. We compared these records of Lincoln’s winter bird populations with historical data found in Johnsgard’s 1988 article in the “Nebraska Bird Review” (vol. 66, no. 3, September 1998). In that article, Johnsgard examined 53 years of Lincoln CBC data, 1909 to 1997. In Table 1 we present the differences in the average number of individuals per year of the most commonly seen species in the two time periods.
The first column lists the most abundant species from 1906 to 1997 and the second column lists the numbers of those same species from 1998 to 2008. Lapland longspurs and horned larks showed the largest drop in numbers. Other data and analyses indicate that these two species are wintering farther north because of global warming. The increases in mallard and Canada geese numbers probably reflect both an increase in the number of man-made lakes in the Lincoln area over the last 60 years and global warming helping to keep those lakes open in the winter. Dark-eyed junco and American goldfinch populations are certainly benefiting from winter backyard bird feeding. The decline in the number of house sparrows reflects part of a national trend.
Participating in Christmas Bird Counts is a great way to celebrate the Yuletide season. To learn more about the Christmas Bird Count tradition, or to find a count in your area, please visit http://cbc.audubon.org. Table 2 lists the counts planned for our area this season. If you are interested in participating in a count, contact the compilers for more information.