Thailand is one of the world's largest prawn exporters. Welfare conditions in Thai whiteleg prawn production have implications for billions of individual crustaceans annually.
Thai prawn welfare in intensive production is compromised by extreme stocking densities that create chronic social stress and water quality deterioration. Disease events including EMS cause mass mortality events that represent welfare crises for affected ponds. Harvest practices involving pond drainage, crowding in diminishing water volumes and subsequent icing impose acute welfare costs at the end of production. The precautionary principle applied to crustacean sentience suggests that the scale of potential welfare harm in global prawn production - affecting hundreds of billions of individuals - justifies significant investment in welfare improvement even under scientific uncertainty.