EBird

eBird is an online database of bird observations providing scientists, researchers and amateur naturalists with real-time data about bird distribution and abundance. Originally restricted to sightings from the Western Hemisphere, the project expanded to include New Zealand in 2008, and to cover the whole world in June 2010. eBird has been described as an ambitious example of enlisting amateurs to gather data on biodiversity for use in science. eBird is an example of crowdsourcing, and has been hailed as an example of democratizing science, treating citizens as scientists, allowing the public to access and use their own data and the collective data generated by others.

Text from Wikipedia, CC BY-SA 4.0