Distribution of zooplankton in selected centres of Cochin backwaters, Kerala

Abstract

Seventeen groups of zooplankton were recorded from nine stations located in the Cochin backwaters during the period from August 2000 to July 2002. Quantitative and qualitative distributions of these groups in the nine stations are presented. Out of the 17 zooplankton groups, 16 groups were recorded from station I (Vypeen) as well as from station VI (Cochin Fisheries Harbour) and the number of groups were minimum (9) at station V (Eloor). The density of zooplankton was maximum at station II (Puthuvypu) followed by station III (Narakkal) with 42% and 39% respectively and the zooplankton density was minimum at station V (Eloor), with 0.66% of the total. Among the different groups of zooplankton available in this area, a maximum of 52% composed of rotifers, followed by copepods which formed 40%. Stationwise studies indicated the dominance of rotifers at stations II, III and VIII while copepods contributed to the maximum in all the other six stations. The results of ANOVA indicated that the variations in zooplankton between stations were highly significant.