The 116th Christmas Bird Count starts December 14, 2015 and runs through January 5, 2016. This longest running Citizen Science survey in the world provides critical data on population trends. It is organized into circles, and each circle counts as many birds as possible on one day, either on a predetermined route, or at their backyard bird feeder. Data is compiled, and used to learn about long-term bird trends.
If you would like to participate, check out the searchable map to find a counting "circle" near you.