Zooplankton Composition and Abundance as Indicators of Eutrophication in Two Small Man-made Lakes

The distribution and abundance of zooplankton species of Harapan and Aman Lakes were investigated in relation to physical parameters and chlorophyll-a content. Both lakes were characterised by the occurrence of algal bloom problem. The composition of zooplankton was collected at monthly intervals from November 2013 to February 2014. The total number of taxa in Harapan and Aman Lakes were 23 and 27, respectively. Rotifera was the highest abundance group represent 64% of the total species recorded followed by Copepoda (29%) and Cladocera (7%). Three dominant zooplankton that been recorded in both the lakes are Brachionus forficula, Brachionus nilsoni, and Trichocerca sp. High abundance of these species indicates that the lakes are eutrophic water bodies. Overall, zooplankton species distribution and abundance in the study sites are influenced by various environmental factors such as water transparency and chlorophyll-a content.