The excretory behaviour of outdoor lactating sows has important implications for sow and piglet health, especially in organic systems, where use of anthelmintics and other medication is restricted. It is also important in determining the environmental impact of the system. If foraging and excretion are spatially separated this limits risk of parasite infection, but may lead to nutrient “hotspot” formation with potential for leaching and poor nutrient cycling to subsequent crops. Where nose-ringing of organic sows is not permitted by the certification scheme, pasture will be destroyed by foraging activity, further promoting nutrient losses. This study aimed to investigate the spatial distribution of excretory behaviour and patterns of pasture loss during the period from farrowing to weaning.