Abundance and Diversity of Zooplankton in Semi-Intensive Shrimp (Penaeus monodon) Farm

摘要

The present study was carried out on the seasonal abundance and diversity of zooplankton in a semi- intensive shrimp farm of Bagerhat district from June to December, 2008. Plankton samples were collected by conical shaped monofilament nylon net (Plankton net) and Lugol’s solution was used for preservation. The zooplankton abundance was influenced by physico-chemical factors. In the present study 5 groups of zooplankton were observed namely rotifer, copepod, cladocera, ostracoda and crustacean larvae. Among the various groups of zooplankton, the percentages of copepod, rotifer, cladocera, ostracoda and crustacean larvae in the culture system were 52%, 39%, 7%, 1% and 1% respectively. The zooplankton was dominated by copepods (52%) which showed more or less two peaks in August (833 individuals/L) and in October (815 individuals/L). Rotifer and copepod were about r awhile one genus Cypris of ostracod was found only in August. Three genus of copepod namely Diaptomus, Cyclops and Mesocyclops were identified in the study area of which Diaptomus and Mesocyclops were more or less dominant while four genus of which Brachionus and Filinia under rotifer and Daphnia and Diaphanosoma under cladocera were also found during the study period. The findings of the present study will help to improve the management strategies of shrimp culture system.DOI: http://dx.doi.org/10.3126/ijls.v5i1.5286 International Journal of Life Sciences Vol.5(1) 2011 1-11