DISTRIBUTION AND ABUNDANCE OF SOME ZOOPLANKTON SPECIES IN NASARAWA STATE UNIVERSITY STREAMS, KEFFI, NIGERIA

The study on Zoological Garden and Cross-three streams in Nasarawa State University Keffi, Nigeria focused on the distribution and abundance of some zooplankton species. Zooplanktons were sampled with improvised fabricated 30cm diameter cylindrical scooper net with attached mesh size of 96pm from the surface of the stream due to the shallowness of the sampling sites and less water volume. There were three major phyla with 12 species of zooplankton found in the two university streams which include Arthropoda, Cilliophora and Rotifera. The phylum Arthropoda has the highest relative abundance with ten (10) species which include; Gammarus fasciatus, Gnathophausia zoea, Cala nus cyclops, Cyclops serrulatus, Harpacticella jejuensis, Corycaeus affinis, Eresia nauplis, Calais parreysii, the order Cladocera of phylum Arthropoda has two species Moinabra chiata and Daphnia pulex while the phylum Cilliophora and Rotifera have one (1) species Euchlanis contorta and Vorticella convallaria respectively. The Station variation of zooplankton distribution was observed to be higher in station I of Zoological Garden stream with 290 (36.9%) followed by station III of Cross-three stream with 289 (29.1%) while stations II and IV recorded 242 and 228 representing 18.5% and 15.5% respectively. The seasonal distribution was high in the raining season with total of 563 representing 52.7% while dry season distribution recorded 468 representing 47.3%. The distribution and abundance of zooplankton of the two university streams (Zoological Garden and Cross-three) shows some relationship between the zooplanktons and the seasons. Higher number recorded during the raining season may be attributed to the volume of the water in the two streams. The finding of this study is therefore helpful to the communities around the streams as the water is relatively safe for domestic use and aquatic life, environmental auditing which involves self-regulation should be encouraged as an overall environmental management policy.