Abstract

The present study is an attempt to know the status of the macrobenthos at the shelf region off Dhamara Estuary. A total of 1870 individulas per square meter of macrobenthic organisms were encountered during the study period. Population density and species diversity was found to be higher as depth increased. Polychaeta emerged as dominate macrobenthic group. Among dominant benthic macroinvertebrates Nereis, Nepthys,Capitella, Owennia, Prionospio, Gammarus, Ampelisca, Tellina, Donax, Dentallium,Echinus etc were predominant in the study region. Environmental parameters like salinity, pH and dissolved oxygen exhibited strong correlation with population density of macrobenthic organisms. Factors 1 and 2 pooled from principal component analysis represented 64.09% of the total variability. The noteworthy aspect of the present study is higher value of population density marked at deeper regions with heterogeneous sediment than shallow depth.

Key words: Shelf region macrobenthos, correlation coefficient, PCA.