Counting Birds: Over a Century of Citizen Science

The coming months are loaded with tradition. For thousands of scientists, conservationists and bird enthusiasts, November means counting a lot of birds.

Of course, observing birds does continue throughout the rest of the year. In fact, one million bird observations are reported to the eBird database on average every month. The span of winter months is a particularly good time to observe birds because of their migratory patterns. With the benefits of this timing in mind, several annual projects compile the observations of both citizen scientists and professionals during designated periods between November and April.

When Did People Start Counting Birds?

The tradition of bird counting dates back more than a century, when ornithologist Frank M. Chapman proposed a more conservation-minded replacement for the traditional "Christmas Side Hunt" - a hunting contest in which participants competed to kill and bring back the most birds and small wildlife. In 1900, Chapman wrote in Bird-Lore magazine:

"Now Bird-Lore proposes a new kind of Christmas side hunt, in the form of a Christmas bird-census, and we hope that all our readers who have the opportunity will aid us in making it a success by spending a portion of Christmas Day with the birds and sending a report of their 'hunt' to Bird-Lore before they retire that night."

Thus the Christmas Bird Count was born, with 25 reports counting about 90 bird species in its first year. More than a century later, tens of thousands of people participate in the annual Christmas Bird Count by noting birds in their area from December 14 through January 5.

There's also Project FeederWatch , which starts in November every year and extends through early April. FeederWatch began in Ontario in the 1970s and expanded to the U.S. a decade later when Canada's Long Point Bird Observatory (now called Bird Studies Canada) partnered with Cornell Lab of Ornithology. Participants in Project FeederWatch survey birds that visit feeders in their communities, backyards, and elsewhere. During periods of two consecutive days with at least five days in between periods, counters record the maximum number of each species visible at any one time during their two-day count. They then report their counts on the project's website.

Cornell Lab launched the Great Backyard Bird Count in 1998 with National Audubon Society, creating the first online citizen-science project to collect and display real-time data about birds. During the four-day Great Backyard Bird Count, participants observe birds anywhere in the world for at least 15 minutes at a time. Each new day and/or new location gets a separate checklist in which counters estimate the number of individuals of each species seen during the designated period. They then submit their observations on eBird, which can also accept photos and sound clips.

Today, thousands of people participate in these two projects alone - more than 20,000 in Project FeederWatch and upwards of 160,000 people from over 130 countries in the Great Backyard Bird Count.

What Do the Observations Show?

The combined data from these citizen science projects help researchers understand factors that affect bird populations over a long period of time. Comparing bird counts, photographs and other data on an annual basis provides insight into species' health, how disease is spread, changing trends in migration and distribution, and much more.

Furthermore, the fluctuation of bird populations shows important implications for both small- and large-scale ecosystems. Bird count data has been particularly instrumental in climate change reports, for example. Data from the Christmas Bird Count revealed to the U.S. Environmental Protection Agency (EPA) that the average winter center of abundance - the midpoint of a species distribution on a map - among 305 North American bird species has moved northward by more than 40 miles since 1966. The northward trends are associated with increasing winter temperatures. This indicator is now among those reported in the EPA's Climate Change Indicators in the United States.

Getting Involved

Want to become a part of a citizen science effort that involves tens of thousands of people from all over the world? Participating is easy and costs little to nothing. The Christmas Bird Count is funded 100 percent on donations, making it free for participants. In addition to supporting counters on count day, the donations fund the management of the database and the technology that powers it. The Great Backyard Bird Count is also supported by donations, and counters can create a free account on eBird to start submitting observations. There's a $18 participation fee for Project FeederWatch ($15 for Cornell Lab members) that supports the project almost in its entirety. The fee covers materials for participants as well as staff support, data analysis, website maintenance, and the year-end report titled Winter Bird Highlights.

Consider adding a new tradition to the season. By joining one or several counting projects, you'll be adding your own data to an important citizen science effort that's more than a century old.