The use of citizen science for marine biodiversity surveys : from species identification to ecologically relevant observations

International audienceThe current development of citizen science is an opportunity for marine biodiversity surveys to use recreational SCUBA diver data. In France, the DORIS project is extensively used for marine species identification, while many initiatives offer volunteer divers the means to record their observations. Thanks to the scientific synergy generated by the flagship project of the artificial reefs (ARs) of Prado Bay, located off the coast of Marseille (France), a multi-annual biodiversity survey was performed by a team of recreational divers certified by the French Federation for Submarine Sports and Education (FFESSM). The analysis of their observations with other citizen science data showed a good taxonomic coverage for fishes and mollusks. These observations also allowed (1) to follow AR colonization over the study period, with the increasing number of taxa and the growing occurrence of large fishes, and (2) to characterize taxa distribution between the different AR types, revealing the inefficiency of one type of AR which failed to provide the results expected from its design. This example demonstrates that the transition from species identification to ecologically relevant observation is perfectly feasible using volunteer naturalist SCUBA divers, on condition that both the protocols and the data are validated by professional scientists