The Oosterschelde is a breeding ground for different species of fish and shellfish and the domain of the mussel famers and fishermen. The mussels are sold in Yerseke, which is also the centre of the oyster farming and also contains a number of lobster farms. Mussels go through a strict inspection and are then cleaned of all sand and possible imperfections are removed before they are sold. The Netherlands is one of the largest mussel exporters, but the consumption in the Netherlands is  also increasing because of the better distribution system. For the first time in a while a mussel day has been held in Yerseke for the promotion of the mussel, on which everyone could try them for free and make a boat trip in a cutter on the Oosterschelde. With the construction of a multiple buttress dam in the Oosterschelde, which will be finished in 1985, the tidal movement in this arm of the sea will be kept and with this also the mussel farming. SHOTS: aerial shot of the Oosterschelde and the building excavation for the multiple buttress dam under construction; drawing of the multiple buttress dam; cutters on the Oosterschelde; underwater fauna of the Oosterschelde, with different fish, a crab and a lobster; several close ups of mussels at the bodem of the sea; mussels are caught and thrown into the hold; aerial shot of Yerseke; bin in Yerske where oysters are stored; lobsters in lobster farms are caught and are packed in crates while still alive; close up lobsters; inspection of mussels for size and amount of meat; selling of mussels at the auction; mussels are packaged in large plastic bags; visitors at the mussel day in Yerseke; decorated cutters with visitors leaving the harbour and on the Oosterschelde.