Could birdwatching or monitoring tree blossoms in your community make a difference in global environmental research? A new study says yes: citizen scientists have a vital role to play.Citizen scientists are already providing large amounts of data for monitoring biodiversity, but they could do much more, according to a new study published in the journal Biological Conservation, which suggests that citizen science has the potential to contribute much more to regional and global assessments of biodiversity. Citizen scientists are regular people who provide data or input to science, for example by monitoring species in their community or examining satellite imagery for evidence of deforestation or land use change. “Citizen scientists are already contributing enormously to environmental science,” says IIASA researcher Linda See. “For example, a huge amount of species occurrence data is provided by members of the interested public. The question we addressed was, where are citizens contributing and where are they not, and how can we draw on this phenomenon to help fill the gaps in science?”