Today"s the first day of the 121st annual Christmas Bird Count, said to be the largest and longest-running citizen science project in the world. For the next 23 days, through January 5, thousands of volunteers around the US, Canada, Latin America, the Caribbean, and the Pacific Islands will join members of the National Audubon Society for this important endeavor in the study and protection of birds. Together, they"ll scour the woods, fields, and lakes of their respective regions (or just watch their bird feeders), to take a census of the individual birds and species they find.