Braithwaite, Carrascosa, and McEvoy conducted controlled field experiments at salmon farm sites in the Scottish Highlands to determine whether the mesh aperture size of cage nets influences biofouling accumulation. Test panels with mesh sizes ranging from standard smolt nets (15 mm half-mesh) to grower nets (25 mm half-mesh) were deployed simultaneously and sampled at regular intervals over a full fouling season from May through October.
The results demonstrated that smaller mesh sizes accumulated fouling biomass significantly faster than larger meshes, primarily because tighter apertures reduce water velocity through the net, creating low-flow microhabitats that favour larval settlement of hydroids, mussels, and barnacles. The study also documented a shift in fouling community composition with mesh size: fine-mesh panels were dominated by hydroids and filamentous algae, while coarser meshes supported proportionally more mussels and barnacles. These findings have practical implications for net selection and cleaning schedule planning.
Salmon farmers managing smolt-stage nets should expect accelerated fouling relative to grower nets and plan cleaning intervals accordingly — the fouling season calendar provides regional timing guidance. For a broader assessment of net management options, consult the anti-fouling solutions comparison.