Mesh Size Regulation

Mesh-size regulation sets the minimum net-mesh opening in a fishery so juvenile fish escape before they are landed, the core technical measure for managing gear selectivity. Larger mesh lets undersized fish pass through while retaining mature targets, raising the size at first capture and protecting recruitment. The EU Common Fisheries Policy fixes minimum mesh sizes by fishery and area, for example 80 mm and 120 mm cod-end ranges in different North Sea trawl fisheries. Square-mesh panels improve escape over diamond mesh, and mesh rules pair with minimum landing sizes to control growth overfishing.