Nature lovers have long tracked the timing of certain events — when plants bloom or when fish swim upstream to spawn — to answer practical questions: When are the best times to hunt and fish? When should crops be planted and harvested? These days, such homespun investigators have come to be known as citizen scientists.
Increasingly, researchers are tapping into the wealth of observations being made by citizen scientists nationwide, a data trove impossible for scientists to gather on their own (or even with a small army of graduate students). One of the largest repositories of such data is maintained by the USA National Phenology Network, founded in 2007.
Last month the organization reached a landmark of more than 1 million observations collected on hundreds of species ranging from alfalfa to Yoshino cherry, the tree whose blossoms beautify the Tidal Basin each spring in Washington, D.C. Shifts in the timing of such events are among the keenest and most