Great Backyard Bird Count

The Great Backyard Bird Count (GBBC) is a community science project in ornithology. It is conducted annually in mid-February. The event is supported by the Cornell Lab of Ornithology and the National Audubon Society. During this four-day event, birdwatchers around the world are invited to count and report details of birds in the area in which they live. Data collected is submitted in eBird an online web interface, and compiled for use in scientific research. The GBBC was the first community science project to collect bird sightings online and display results in near real-time.

Text from Wikipedia, CC BY-SA 4.0