Last fall the National Audubon Society published an alarming report about the future of North American birds. Of the hundreds of species that they studied, more than half are threatened with extinction as a result of climate change. Accompanying the report was a series of animations, produced by the San Francisco firm Stamen Design, showing how each threatened bird's home range could shift over the next 65 years. Many of the maps showed suitable habitat drifting north in response to rising temperatures and in some cases disappearing. The breeding grounds of birds such as the eastern whip-poor-will and the Baird's sparrow, a tiny grassland bird native to the northern plains, may all but vanish.
Several news organizations, including National Geographic and the New York Times, published graphics of their own using the Audubon data, which came from a sophisticated analysis of global climate conditions. One of the less talked about aspects of the Audubon report was its baseline data—observations about habitat ranges that had come from amateur bird-watchers.
The Audubon report reflects the rise of crowdsourcing, in which masses of private citizens contribute to collective projects. Thanks to smartphones, the Web, and cloud computing platforms, individuals around the world can help identify wild animals in safari parks, categorize the emotions evoked by literary excerpts, classify galaxies, or just draw pictures of sheep. When crowdsourcing extends beyond typically low-level validation tasks to more profound analytical contributions, it enters the realm of citizen science.
What is citizen science? "Observations of nature made by people who were not trained as scientists," says Mary Ellen Hannibal, author of the forthcoming book Citizen Scientist. By that measure, she says, "Even Darwin was a citizen scientist, because he was not affiliated with any institution. He didn't have higher degree—he had a bachelor's."
Amid the fuss surrounding aerial drones, remote sensors, and the new satellite imagery that's coming online, it’s easy to forget the contributions that motivated and smartphone-equipped individuals can make to science, whether by hiding in bird blinds, splashing through tide pools, scaling mountain peaks, or sitting at a desk. "It's really incredible what satellites can do," says Hannibal, "but that information needs to be ground truthed." In bird-watching, she adds, "birds are hard to identify, and human eyeballs are still better at that."
The bird surveys that informed the Audubon report have a surprisingly long history.