Distribution of the zooplankton

This study was carried out at Ondiri swamp, Kiambu County, Kenya. It aimed at assessing the zooplankton distribution and its relationship to the physico-chemical water parameters. Eight sampling points were selected randomly among which, four were from the littoral zones of the swamp while the other four were at the pelagic zones. The sampling points were named Site 1, Site 2, Site 3, Site 4, Site 5, Site 6, Site 7 and Site 8. Four physico-chemical parameters were assessed, namely water pH, temperature, turbidity and dissolved oxygen (DO). Zooplankton was collected by drawing water using a 20-litre pail and then sieving the water through a 0.2 mm mesh size zooplankton filter. In addition, some were collected through horizontal towing using a 15 cm diameter x 60 cm long size zooplankton net. A total of six orders of zooplankton were identified namely: Order amphipoda, Hemiptera, Odonata anisoptera, ephemeroptera, plecoptera and coleoptera. Plecoptera had the highest number of species while the fish larva had the least. Site 1 had the highest relative abundance of 25% owing to its closeness to the farms.