Aspects of the ecology of intertidal barnacles on the shores of Peninsular Malaysia and Singapore

Abstract

Spatial and temporal variations of recruitment and population dynamics of intertidal barnacles Balanus spp. and Chthamalus malayensis were examined on the shores of Singapore and Southern Peninsular Malaysia from August 2003 to April 2005. This study addresses the lack of comparable knowledge for tropical shores. Variability of C. malayensis adult density, recruitment and mortality were examined over three spatial scales (tens of metres - 100s of kilometres) in Malaysia and Singapore over one year, and temporal patterns were investigated by charting monthly recruitment, three-monthly changes of densities and mortality rates. Vertical and temporal variation of Balanus spp. recruitment and juvenile mortality was examined on Singaporean shores using settlement plates. All analyses revealed significant interaction between the smallest scale examined (10s m) and time, indicating the local processes are more important than regional mechanisms. Vertical pattern of recruits also showed the vertical distribution of Balanus spp. is not determined by recruitment.