Global Marine biodiversity data from Seawatchers Marine Citizen Science Platform 1980-2020

Observadores del Mar is a marine citizen science platform launched in 2012 devoted to enhancing the understanding of the conservation status of marine ecosystems. The platform hosts 13 projects covering 8 main taxa: corals, jellyfishes, decapod crustaceans, fishes, seaweeds, seagrasses, seabirds and molluscs, in addition to two projects focused on marine litter and reporting information on two main topics: i) biodiversity data focusing mainly on species distribution and abundance, and ii) the impacts of anthropogenic activities (e.g. jellyfish blooms) and associated mid- to long-term changes (e.g. colonization of invasive species). Almost 5500 observations validated by scientists have been already collected resulting in more than 20 scientific papers and communications. The major findings have been new records of introduced and invasive species, tracking the spread of novel pen shell mortality outbreak in the Mediterranean Sea and monitoring microplastic concentration on beaches.