Effect of monsoon on zooplankton variations and environmental characteristics in a tropical fish pond at Aligarh, India

The phsico-chemical parameters and zooplankton abundance were analyzed monthly in Lal Diggi pond at Aligarh, India during the period from October, 2010 to August, 2011. High variations of zooplankton and water quality were observed in the pond. Thirty nine species were identified belonging to Copepoda (3 species), Rotifera (27 species), Cladocera (6 species) and Protozoa (3 species). Copepoda formed the highest percentage of zooplankton (66.65 %), followed by Cladocera (14.93 %), Rotifera (9.61 %) and Ostracoda (8.61 %), while Nematoda and Protozoa formed the lowest dominant groups being 0.15 % and 0.05 % respectively. The principal component analysis was conducted to clear the correlation between zooplankton and the environmental factors. Due to the disturbance effect on the pond, the biotic indices recorded a relatively decrease during monsoon in June and July and start to increase during August. The authors suggested that, using the pond for fish culture, especially, after monsoon for six months (from October to March) because it has the best water quality and zooplankton productivity during this period.