The Great Backyard Bird Count takes place this Friday-Monday.

Anyone can participate — it’s as easy as stepping into your back yard and marking down what birds you see. The result is a real-time snapshot of what birds are doing around the country.

Last year’s bird count, for example, found that many species of birds were already migrating in February, earlier than in past decades. In total, participants last year sent in more than 80,000 checklists showing 11 million birds from 613 species.

Participating in the count takes just three steps:

1. Plan to count birds for at least 15 minutes between Friday and Monday. Keep a separate list of counts for each day or location you choose to count.

2. Count the greatest number of individuals of each species that you see together at any one time, and write it down.

3. Enter your results at the Great Backyard Bird Count.

This year, participants can also submit video of birds to YouTube, with the best video posted on the Great Backyard Bird Count’s Web site.