Ecology of the cladocerans of the plankton community in the Cochin backwater

Occurrence and seasonal changes in the distribution of two cladocerans in the eochin Backwater, Evadne tergestina Claus and Penilia avirostris Dana have been considered. Fluctuations in temperature of tbe estuary are of the order of SoC., while tbe cbanges in salinity are considerable. Seasonal variation in distribution of tbe two species bas been correlated with temperature and salin ity in T-S-P diagram for a period of fifteen months. Their numerical abundance month-wise bas also been investigated. A comparative study of the distribution of cJadocerans of the insbore waters of India wilh that of the Cochin Backwater has also been carried out