Effects of cage encrustation by the bryozoan Plumatella casmiana on production of channel catfish

Fouling by the bryozoan Plumatella casmiana was observed on cages in which channel catfish (Ictalurus punctatus) were being reared for a strain evaluation study at the Fish Farming Experimental Station, Stuttgart, Arkansas. Channel catfish growth was inversely correlated with encrustation. The extent of the encrustation was inversely related to pond water depth and to the distance of the cage from the pond water supply inlet. Fish growth was reduced in the cages most heavily fouled, which were in the shallowest water and nearest the water inflow.