Biology of marine fouling in Mangalore waters

Abstract

A comprehensive study of the fouling organisms encountered at the New Mangalore Port at Panambur and the Fish Landing Jetty on the Nethravati-Gurpur estuary near the old Mangalore Port, India, was made. Barnacles, oysters, bryozoans, polychaetes and hydroids are the dominant groups of foulers encountered in this region. Barnacles are by far the most important foulers. Distinct seasonal abundance in settlement was noticed in the different groups. The major peak settlement of barnacles occurs in November and December. Continuous settlement of this group in the harbour indicates the presence of larvae throughout the year in the marine locality. The absence of freshly settled spat in the estuarine locality shows that these larvae do not foul structures in the Fish Landing Jetty during the monsson period. The pattern of oyster settlement indicates that the spat of Crassostrea madrasensis and c. cucullata settle during January, March, May and October in this region. This group remains in the fouling community throughout the year. Only typical marine bryozoans are harboured in abundance in the fouling community. Polychaetes occur in great numbers during April and December.The differences in the quality and quantity of the fouling communities are controlled by their breeding periodicity,seasonal fluctuations in the hydrographical conditions, and the species composition of the sedentary community of this region.