Observations made on recruitment of fouling organisms on treated panels exposed at an Indian harbour, Krishnapatnam on the east coast (Lat: 13028’ to 13059’ N; Long: 80010’ to 80016’ E) during November, 1997 to October, 1999 are reported and compared with fouling communities on control panels. Wooden panels of Erythrina variegata, Paraserianthus falcataria, Tetrameles nudiflora and Trema orientalis treated with 2 chemical preservatives i.e. CCA (Copper-Chrome-Arsenic) and CCB (Copper-Chrome-Borate) at four retention levels for each preservative (8, 16,24 and 32 Kg/m3) and one water repellant i.e. Chromic acid (8 % solution) was used in this studies. It was observed that the preservative (CCA,CCB) treated panels had greater initial settlement of barnacles, oysters, bryozoans and algae compared to untreated control panels. Serpulid settlement was heavier on untreated panels. Barnacles exhibited greater affinity for settling on CCA treated panels compared with CCB and Chromic acid. However, their settlement was lesser on panels with higher loadings (32 Kg/m3) in all treatments. Fouling communities settling on CCA treated panels showed retarded growth compared to CCB treatment but higher than controls. Oyster settlement was found to be more on CCB treated panels. The biomass and growth rates were high on CCB treated panels compared to CCA treated panels. On chromic acid treated panels, bryozoans and algal settlement was heavy but barnacles and oysters settlement was negligible. The biomass recorded also was lower than those of CCA, CCB and control panels. Fouling organisms also had lesser growth rates. Copper , chromium and arsenic levels were estimated in soft tissues of Balanus amphitrite and Crassostrea madrasensis that settled on treated panels. The values indicated that copper accumulated more in tissues followed by arsenic and chromium. Metal levels were found to be higher in C. madrasensis than B. amphitrite.

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