On the zooplankton of the inshore waters of Karwar during 1980-81

Abstract

Studies conducted during 1980-1981 have shown that there is a good standing stock of holoplankton in the inshore waters of Karwar, in addition to frequent swarms of meroplankton. The variations of both numerical abundance and total biomass are bimodal, one peak occurring during March-April and the other in September or October. Whereas the broad-based March-April peak is a conglomeration of varieties of holo- and meroplankters, the narrow and sharp September| October peak is in the main constituted by sudden and acute swarmings of one or the other of the two cladoceran species Evadne tergestina and Penilia avirostris. Owing to this constitutional difference, the distribution of biomass, though is concurrent with that of the numerical abundance, does not keep a magnitude similar to the latter; whereas the peaks of both numerical abundance and biomass go hand in hand in March-April, the peak of the latter is far less pronounced than that of the former in September|Octobcr.