The bioturbation by sea turtles in Italian mussel farms: first national data collection

Sea turtles play a role as sources of disturbance in mussel farms. The increase in the number and distribution of mussel farms has resulted in ever-increasing bioturbation by sea turtles. Although it is now well known among aquaculture operators that the bioturbation of mussel farms by sea turtles causes several damages and a significant economic loss that is not estimated yet, currently there are no data available on this matter to support this evidence. This represents a knowledge gap not only from an ecological and biological point of view but also for the management of mussel farms that bring a considerable economic income for several regions in Italy (estimated around 74 972 t) . In the present study, the frequency of Mytilus galloprovincialis ingestion was inspected from the digestive tract content of Caretta caretta, and an assessment questionnaire was designed and submitted to 32 aquaculture operators involved in mussel farming in Italy. The data collected were processed to investigate the incidence of the phenomenon, including possible common factors among the farming plants. The results clearly show that mussel is a frequent food preyed on by C. caretta and that the bioturbation of this species is increasingly causing remarkable damage to Italian mussel farmers. As mussel farms plays an important ecological role drawing a mixed trophic activity, it’s crucial to gather data on the species interacting with farming plants to preserve the ecological balance along with the economic activity.