Scientists by chance: reliability of non-structured primary biodiversity data. Insights from Italian Forums of Natural Sciences

Abstract

Forums and social networks store a big deal of data on flora and fauna, collected especially by amateurs. To what extent are these data useful to contribute to biodiversity data systems? In this paper, we addressed the question about the "suitability for use" of primary biodiversity data by exploring two popular and valued Italian Forums of Natural Science (Forum Natura Mediterraneo and Forum Entomologi Italiani) and tried to assess their scientific potential. The aim of our work was to evaluate and discuss taxonomic reliability of the identification of butterfly species and the accuracy of their geographic locations. For each forum thread, we examined the posted images of butterflies, checked the diagnoses and georeferenced the observations from the textual descriptions provided by the users. Then, we compared each final identification by users with an independent identification by expert taxonomists. Looking at species level identifications, users identified 3764 out of 4029 specimens (93.4%) and experts agreed with them in 3649 cases: a high percentage agreement (p_o = 96.9%). As for the geographic data, we were able to georeferenced 97.9% of the observations (70% with an estimated extent less than 2500m). Results of this study, although limited to butterflies, suggest that the final identifications from forums show a surprisingly small bias and that the 'democratic' approach to taxonomy ultimately produces few uncertainties. The selected forums contain large amounts of primary biodiversity data in digital format, correctly identified and georeferenced with satisfactory accuracy and this capital is too valuable to remain unused. The formalization of collaborations with scientific projects and institutions would bring the forums in the area of “official” citizen science initiatives, giving the forums a role of citizens' scientific training. The recognition of a scientific role makes forum managers and users more deeply involved and data protection over time, currently entrusted to forum managers, would be greatly enhanced.