The establishment of kelp grids for seaweed cultivation in the 18th Century marks the first aquaculture activity in Strangford Lough. Seaweed cultivation and harvesting for soda production probably continued for over 100 years until its demise in the 1830s when it became uneconomic (McErlean 2002). This period probably represents the greatest impact on the intertidal areas of the Lough in recorded history. Experimental studies into the growth of the oysters Crassostrea gigas and Ostrea edulis by Parsons (1974) and Briggs (1978) demonstrated the suitability of Strangford Lough for oyster culture and stimulated its development in the Lough. Consequently, aquaculture in the Lough, which started in the 1970s with a few producers, focused initially on oysters (Figure 1). For example, Cuan Oysters, which was established in 1974, played an important role in the development of aquaculture in the UK by pioneering culture methods for very small hatchery-reared oyster seed. Cuan Oysters is currently the major producer of oysters in Strangford Lough, and one of the main producers in the UK, handling over 400 tonnes of oysters per annum ( Aquaculture in Strangford Lough continues to focus entirely on bivalves but now includes mussels and scallops as well as Pacific and native oysters. This section reviews the development of aquaculture since the 1970s in the context of recent ecological changes and the Shellfish Aquaculture