Audubon Christmas Bird Count
Count Birds. Change the World.
For more than a century, the Audubon Christmas Bird Count has brought together thousands of volunteers across the Americas to count birds for conservation. What began in 1900 has become the world's longest-running bird count.
Get InvolvedOver a Century of Discovery, Powered by You
More Than a Century of History: No other dataset can answer questions about what bird communities were like in 1920, 1950, or 1980 with such geographic scope—providing the historical baseline essential for understanding what we're losing, what we're saving, and which conservation actions to prioritize.
A Method That Endures: Volunteers return to the exact same counting circles year after year, counting birds during the same window of time using a standardized protocol. This consistency—same places, same methods—allows scientists to distinguish real population changes from random variation.
Real Conservation Impact: CBC data has revealed dramatic declines in grassland birds, documented species range shifts due to a warming change, and contributed to over 300 peer-reviewed scientific publications that guide protection strategies.
Community at Its Core: The true heart of the Christmas Bird Count is its people—families, students, bird clubs, and first-timers building lasting bonds with the natural world and each other.
Our Story
Since 1900, the Christmas Bird Count has transformed the simple joy of birdwatching into one of the world's most important records of environmental change. Each year, thousands of people across the Americas and Pacific come together to count birds within designated local areas called counting circles. What begins as a single observation becomes part of something far greater: scientific data that reveal population trends, community connections that span generations, and conservation action that protects the birds and places we all depend on.
The Christmas Bird Count welcomes everyone, from experienced birders to those just beginning to notice the natural world around them. No expertise is required—just curiosity and a love of birds. Whether you join a field group, monitor your backyard feeder, or help compile data, participation is coordinated through local circle leaders who guide volunteers through this meaningful tradition. First-timers are often paired with experienced counters. You don't need to know every species; you just need to show up ready to notice.
Join your count to help us change the world for birds and people.
Anytime between December 14 and January 5 every year. The leader of each count circle (called a Compiler) picks one day within that window, ideally using the same time each year for consistency.
Anyone! The Christmas Bird Count is open to all ages and experience levels. Participation must be coordinated in advance with a local count leader. Most counts allow sign-up through the online Circle Finder.
The Christmas Bird Count is a collection of thousands of local counts held within designated circles that are 15 miles/24 kilometers wide throughout the Americas and the Pacific. To find a count circle in a specific location or on a specific date, use the Circle Finder.
By concentrating thousands of volunteers into a single-day effort within each circle, the Christmas Bird Count creates a comprehensive "snapshot" of bird communities once a year. This captures rare species and provides robust abundance estimates that casual observation would miss.
There are several types of roles, but they fall under the categories of volunteers and leaders. In general, volunteers count the birds and leaders coordinate volunteers and organize the local count. You can find a detailed explanation of the roles here.
Four types of data are collected during every count: dates and times, observer effort, weather, and bird observations. See the CBC guide for more details.
A Christmas Bird Count guide that provides an overview of the count, its history, basic protocol information, and engagement tips is available in four languages.
We highly encourage all leaders to review modernization updates and join or watch related training sessions. Check out the CBC leader modernization resources webpage where you can participate in or review training webinars and access project updates. You can find more detailed instructions about the new Christmas Bird Count data platform in the Christmas Bird Count Data Entry Platform How-To section of the Resource Hub.
The Christmas Bird Count is made possible by many partners across the hemisphere. Visit our partnerships page to learn more.
Christmas Bird Count 101 Webinar
Curious about the Christmas Bird Count (CBC) but not sure where to start? Join us for an introductory webinar designed for anyone interested in participating in this longstanding community science tradition.
Register Here