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The original version of this article was revised to standardize units of measurement. The changes are underlined as follows: 9th sentence under AbstractCatch rates varied between River Nile (1.92 ± 0.59 Kg boat -1 day -1 ) and the rest of the systems, 6.20 ± 1.86 and 6.85 ± 1.49 Kg boat -1 day -1 in Lake Edward and Kazinga channel respectively. 11th sentence under AbstractDissolved oxygen was below the minimum of 5 mgl -1 required for the physiology of freshwater fish. 12th sentence under AbstractConductivity was highest in Lake Edward (312 μS cm -1 ), followed by Kazinga channel and least in River Nile. 5th sentence, paragraph 2 under IntroductionCatch rates in the Lakes Victoria and Edward basins reduced to the lowest levels of 0.5 to 0. 5. 1st sentence, paragraph 2 under Water quality data collection Dissolved oxygen (mgl -1 ), water temperature (°C), electrical conductivity (μS cm −1 ) and pH were determined using Yellow Spring Instrument (YSI, model 556) at

Phytoplankton, zooplankton and macrozoobenthic invertebrates are important elements in the structure and functioning of aquatic systems. There is, however, limited information to aid in understanding the interactions between these organisms and their environment. The three groups were examined along a horizontal water chemistry gradient in Lake Kwania. The lake was subdivided into three zones: west, central and east, similar to what was earlier described for Lake Kyoga. Conductivity, silica and Secchi depth showed significant horizontal differentiation between zones. Conductivity (126.3, 209.2 and 289.1 μS/cm) and silica concentration (1419.9, 3708.0, 9146.3 μg/L) increased from the west to the east zone. The composition, abundance and taxonomic diversity of phytoplankton, zooplankton and macrozoobenthic invertebrates did not show a significant pattern along this gradient. Cyanobacteria dominated by Planktolyngbya limnetica; Copepoda dominated by Tropocyclops tenellus; and Diptera dominated by Chaoborussp, were respectively the most abundant phytoplankton, zooplankton and macrozoobenthos across zones. These results suggest that other factors control these organisms in addition to the lake's water chemistry. It is critical to investigate these factors further to fill knowledge gaps that will aid in the future conservation and management of Lake Kwania, the Kyoga Lakes in general and other Great Lakes.