The Christmas Bird Count: How to Join Birding's Oldest Tradition

The Christmas Bird Count (CBC) is the longest-running community science project in the world, and one of the most welcoming ways to get involved in birding. Every winter, tens of thousands of volunteers fan out to count birds — and you can join.

What the CBC is

Organized by the National Audubon Society since 1900, the CBC replaced an old tradition of holiday bird hunts with a bird count. Each count takes place on one day within a set period (mid-December to early January) inside a fixed 15-mile-diameter 'count circle,' with volunteers tallying every bird they can find.

Why it matters

More than a century of consistent data makes the CBC a goldmine for understanding long-term trends in early-winter bird populations and ranges. It has documented range shifts, declines, and the effects of climate — a true scientific legacy built by everyday birders.

How to join

1. Find a count circle near you through the Audubon CBC website.
2. Contact the circle's compiler to sign up — beginners are welcome and usually paired with experienced birders.
3. Get assigned an area or join a team for count day.
4. Count every bird you see and hear, then report your tallies to the compiler.

What to expect on count day

Expect a long, cold, rewarding day in the field — dawn to dusk for the dedicated, or a few hours if that's what you can give. Feeder-watchers within a circle can even contribute from home. There's often a tally dinner afterward to share the day's totals.

Make your count easier

Use Birder AI to confirm tricky winter birds and sound-ID the ones you can't see, and keep an accurate running list. Your careful counts become part of a dataset that has shaped bird conservation for over a hundred years.