Natural history forums as source of valuable biodiversity data

One of the most interesting developments in the impact of Internet on the environmental sciences is the increasing involvement of non-scientists in scientific projects. Among the scientific activities so far less investigated there are the natural history forums, where users exchange knowledge and opinions by sending photos and messages. Forums dedicated to discussions on the natural sciences usually do not represent and do not carry out any project, including those of Citizen Science but, over the years, have accumulated large amounts of data on flora and fauna that could be important and constantly updated sources of primary biodiversity data. To test the suitability of these data we analyzed the threads about butterflies from two of the most preeminent Italian natural history forums: Natura Mediterraneo (FNM) and Forum Entomologi Italiani (FEI). For more than 4,000 observations we assessed the matching level between the identifications in the forums and ours own and the degree of accuracy of spatial description was evaluated too.According to the results, the observations from the examined forums can be considered useful sources of biodiversity data both from the reliability of identifications and from spatial precision. Further tests are under way on different taxonomic groups that may present different problems both for identifications from images and for the accuracy of geographical references. We suggest that massive data recovery from forums through the automatic interpretation of forum threads should be carefully evaluated.