Biodiversity and Ecology of Bryozoans from the Bay of Bengal, East coast of India

Abstract

The ecological record of bryozoans from the continental shelfslope region of the southwestern Bay of Bengal is very sparse, prompting this investigation. Forty-five sea-floor sediment samples were collected along eight transects during the cruise on R/V Sagar Paschimi from the offshore region between Chennai and Cuddalore in the southwestern Bay of Bengal. The distribution of bryozoans was assessed based on the fragments of bryozoan colonies from these samples, which were collected at depths ranging from 6-308 m. The goal was to determine the relationship between environmental parameters measured from the study area and the abundances of various bryozoan species. Results revealed the presence of 29 species of recent bryozoans in 24 genera pertaining to eight morphotypes. It is evident from the present investigation that the major control on the spatial distribution of bryozoan colonies is the type of substrate available, as sample sites dominated by coarse sediments showed high species richness though other factors such as ocean dynamics and rate of sedimentation also seem to regulate their abundance.