Information about early cultivation of bivalves in the Valle di Muggia is lost in the mists of time. The fishermen, descendants of the “salineri”, or workers in the old salt flats, would thrust branches and poles of oak into the seabed far from the beach, and these would attract the young oysters on the lower part and mussels on the upper part; the young oysters and mussels would then be placed for three years in suitable protected areas, such as the Valle di Zaule. Every ‘tree’ could provide up to approximately 100 kg of bivalves, which would be cleaned aboard the boats and then taken to the “ostrigadori” (‘oystermen’) waiting on the shore. The system of oyster beds on poles (in the French manner with supporting partitions for the collectors and nets for seeding) was implemented by the Società austriaca di Pesca e Piscicoltura marina (‘Austrian fish and fish farming company’) in the bay of Muggia, and by the end of the nineteenth century, this provided a living for 32 families, which annually would look after about 20,000 poles and offer an annual harvest that was never less than 100,000 oysters. Various attempts were made to improve production, developing cultivation also in the lagoon of Grado, but the First World War and the pollution that appeared in the bay of Muggia resulted in oyster farming being abandoned. It reappeared in the 1970s in the lagoon of Grado with the Compagnia di Ostricoltori Triestini, with the gathering of natural beds in the Gulf, but this was little by little replaced with the farming of mussels.