David Ouma, a Graduate Fellow at National Museums of Kenya (NMK) holds an undergraduate degree in Wildlife Ecology and Management (Chuka University) and a Master of Science in Biology of Conservation (University of Nairobi). David’s experience spans 5 years particularly in the areas of wetlands and fisheries research, biodiversity mapping, ecological monitoring, and community-based conservation. His research work has contributed immensely to NMK research collection, he was able to scientifically collect and document over 3000 specimens of 15 fish species in the floodplain wetlands of lower River Tana. These are now available as reference collections at the Ichthyology laboratory. Ouma also worked with The Nature Conservancy (TNC) as a fisheries specialist intern for six months. Notably, he provided technical support during baselines surveys on Lamu octopus fisheries. He helped plan and facilitate field activities including community meetings, training, and reporting. This work is helping inform the establishment of new temporary octopus closures and the improvement of women's participation and benefit from fishing. Ouma is an alumnus of the Tropical Biology Association field course 2018 held at the Mpala Research Centre. He is also trained in GIS and Remote Sensing and undertaken Kenya Fish Taxonomy and FishBase course. Ouma has attended thematic workshops on mangroves and hydrology in Madagascar and Mozambique respectively. He is currently seeking Ph.D. opportunities.
Project Summary
Floodplain fisheries resources are under frequent disturbances due to seasonal variation in flood peaks and intensity. This study investigated the influence of flooding on fish diversity and fisheries patterns in the floodplain lakes of lower Tana river, Kenya. Fish diversity and abundance in the floodplain lakes were assessed in relation to changes in space and flooding period. The impacts of seasonal flooding on annual fishing pattern and governance in the Tana River delta lakes was also investigated. Fish was sampled by using monofilament gillnets, and six water quality parameters (pH, temperature, dissolved oxygen, electrical conductivity, salinity and water clarity (turbidity)) recorded using multi-metre probe (YSI Model 85/50) and turbidity tube at three sampling points in each lake in pre-flood, during flood and post-flood period. A total of 2982 fish comprising 15 species in 9 families, were captured. The predominant species in the floodplain lakes were Zanzibar barb (Enteromiuszanzibaricus, 41%), Gregori’slabeo (Labeogregorii, 11%), Red-fin robber (Brycinusaffinis, 8%) and Sabaki tilapia (Oreochromis spirulus, 7%). Non-metric multidimensional scaling (nMDS) plots showed a high similarity of fish assemblages during floods in the floodplain lakes. Pearson’s correlation matrix showed fish abundance was positively correlated with increasing dissolved oxygen (p<0.01), and water depth (p<0.05). Hydrological connectivity influenced fish species composition and abundance. This study therefore recommends preservation of river-floodplain connectivity to conserve fish biodiversity in the floodplain lakes.