Tassonomia integrativa e coinvolgimento degli allevatori per tracciare i vermi parassiti non-nativi Polydora nell'ostricoltura dell'Adriatico

Molluscs’ farming is one of the main vectors for the introduction of non-native species (NNS) in the Mediterranean. We herein present the results of extensive transdisciplinary research on non-native species and polydorin polychaete pests in mollusks farms in the Adriatic Sea. Oysters were samples from farms along Italian, Slovenian and Croatian coasts, while mussels were sampled from few Italian Nord Adriatic farms. Moreover, survey was done with Italian mussels and oysters’ farmers to get insights in their Local Ecological Knowledge (LEK) regarding non-native and pest species in aquaculture and mollusks’ translocation activities that might contribute to their expansion. By combining morphological and molecular analyses, we revealed for the first time new non-native Polydora pests in the Mediterranean, Polydora websteri and P. caeca, boring in mussels and oysters’ shells. Composition of polydorins was different between Italian, Slovenian and Croatian coasts, which may be caused by different farming techniques, translocation practices or farmed species along the three coasts. Most of the molluscs’ farmers knew what non-native species are but only few of them were able to precisely indicate a limited number of species. Moreover, they observed increasing abundance of Polydora in their farms. Farmers reported translocations of juvenile and adult mussels and oysters between Italy, Greece, France and Spain, both within and outside the Mediterranean basin. Our results confirm that integration of morphological and molecular taxonomy and involvement of mussels and oysters’ farmers are crucial to detect new non-native species, reveal their distribution in the basin and draw hypothesis on their introduction and spreading pathways. Training programs should be implemented to improve farmers' ability to recognize non-native species and contribute to their early detection. Furthermore, cross-border collaboration between scientists, policymakers, and farmers is crucial to reveal non-native and pest species and limit their spread through aquaculture in the Mediterranean. Our ongoing and future research activities are going in this direction.