Citizen science can broadly be defined as the involvement of volunteers in science. Over the past decade there has
been a rapid increase in the number of citizen science initiatives. The breadth of environmental-based citizen
science is immense. Citizen scientists have surveyed for and monitored a broad range of taxa, and also contributed
data on weather and habitats reflecting an increase in engagement with a diverse range of observational science.
Citizen science has taken many varied approaches from citizen-led (co-created) projects with local community
groups to, more commonly, scientist-led mass participation initiatives that are open to all sectors of society. Citizen
science provides an indispensable means of combining environmental research with environmental education and
wildlife recording.
Here we provide a synthesis of extant citizen science projects using a novel cross-cutting approach to objectively
assess understanding of citizen science and environmental monitoring including: 1. Brief overview of knowledge on the motivations of volunteers.
2. Semi-systematic review of environmental citizen science projects in order to understand the variety of
extant citizen science projects.
3. Collation of detailed case studies on a selection of projects to complement the semi-systematic review.
4. Structured interviews with users of citizen science and environmental monitoring data focussing on policy, in
order to more fully understand how citizen science can fit into policy needs.
5. Review of technology in citizen science and an exploration of future opportunities