Benthic macroinvertebrates of Dandaru Reservoir were sampled at five stations monthly from April 2015 to March 2016 using van Veen grab (for open water biotope) and modified kick sampling method(for bankroot biotope). A total of 20 macroinvertebrates taxa comprising of 7,945 individuals were recorded in the reservoir during the period of study. Gastropods (76.4%) were the most abundant followed by insects (15.7%) and arachnids (0.89%) being the least. Melanoides tuberculata, Bellamya unicolor and Bulinus differed significantly (p< 0.05) between the sampling stations. More macroinvertebrates were encountered in the rainy season (51.6%). The Margalef’s Index, Shannon diversity, Evenness index and Simpson dominance index were higher at station 1. The domination of the macroinvertebrate community structure of Dandaru Lake by pollution tolerant taxa and the low diversity index indicates the lake is under pollution stress.
Key Words: Macrozoobenthos, Bankroot biotope, Diversity indices, Spatial variation