Citizen or participatory science programs  on biodiversity involve volunteers, most often at the data collection level (Figure 1). Depending on the case, they are addressed to experienced naturalists or volunteers with no particular skills, who thus see the opportunity to acquire knowledge in the natural sciences. Researchers define precise, reproducible, simple protocols that must be used rigorously by participants. They analyze the data collected and provide feedback to observers to inform them of the use of their data.
In France, many programs exist. One of the most important is managed by the Centre for Ecology and Conservation Sciences (CESCO) at the National Museum of Natural History. These are Vigie-Nature , itself composed of many variants involving different taxonomic groups. Some are generalists and are interested in the French territory as a whole, including cities: Temporal Monitoring of Common Birds (STOC)  or Vigie-Flore  In particular. Other projects are clearly dedicated to the urban environment. First of all ” Sauvages de ma rue ”  which asks the general public to send inventory data on sidewalk flora, then the” Observatory of Garden Biodiversity” (OBJ)  which lists birds, butterflies, snails and garden bumblebees, and finally Lichen go  whose object is the lichen growing on urban tree trunks.
The programme Sauvages de ma rue has, for example, made it possible to know the evolution of flora since 1883 by comparing data collected by observers since 2011 and data collected by the botanist Joseph Vallot in Paris. The results show that the disappearance of horses in favour of cars, rising temperatures, soil pollution and the arrival of exotic species are the factors that have most influenced the observed changes (publication in progress).
Notes and references
Coverage image. [Source: © Nathalie Machon]