Biomass and composition of zooplankton in the nearshore waters of Thal, Maharashtra

Abstract

Biomass and composition of zooplankton in the nearshore waters of Thal, Maharashtra, India were studied at 9 stations during Feb. 1980 to Jan. 1981. The recorded variation in zooplankton biomass was 4.8-80.6 ml.(100 m³)^-1 [av. 22.9 ml. ml.(100 m³)^-1]. High biomass observed along the nearshore water during the premonsoon period shifted towards the offshore area with the advent of the monsoon. Zooplankton production was maximum in the postmonsoon season. Mean rate of secondary production for the survey area was 39.12 mgC.m^-2.d^-1. The fishery potential of the area of investigation was estimated to be 1554 t.y^-1. There was gradual increase in zooplankton towards the offshore area with concomitant increase in diversity. Larval forms of echinoderms, cephalopods and brachiopods were confined to the offshore stations. Pycnogonids were recorded for the first time from the West Coast of India.