This study investigated the suitability of small water bodies (SWBs) in the Lake Victoria basin, between November 2010 and October 2011 for increased food production through aquaculture. Sampling sites were stratified in terms of water availability and altitude. Low-altitude sites were represented by Yenga and Mauna dams in Siaya County, while high-altitude sites were represented by Kesses and Kerita dams in Uasin Gishu County. Variations in selected water quality parameters, nutrients, primary productivity (PP) and macroinvertebrate biomass of SWBs were investigated. The measured biological and water quality parameters measured in this study included PP of phytoplankton, macroinvertebrate biomass of the most abundant taxon, temperature, dissolved oxygen concentration, biochemical oxygen demand, pH, total nitrogen concentration and total phosphorus concentration. Descriptive statistics of mean and standard error of the mean were conducted for water quality parameters and nutrient levels. The general linear model was used to test for significant difference in nutrients and physicochemical parameters, both within and between the SWBs. ANOVA was used to test for any significant differences in both PP and biomass within and between the dams. PP and macroinvertebrate biomass were sufficiently high to support fish production, while all water quality parameters and nutrients were within acceptable ranges to support the life of the mostly cultured species. Based on the results of this study, the stocking of phytophagous and benthophagous fish is recommended as a means of exploiting the food resources and increasing fish production in these areas. 7.5 AE 0.23 23 AE 0.33 7.0 AE 0.50 3.4 AE 0.15 1.3 AE 0.06 0.20 AE 0.012 7.3 AE 0.09 22 AE 0.18 7.0 AE 0.45 3.0 AE 0.12 1.8 AE 0.05 0.12 AE 0.015 March 2011 7.6 AE 0.12 23 AE 0.42 7.4 AE 0.46 3.8 AE 0.25 1.4 AE 0.12 0.18 AE 0.009 7.5 AE 0.18 23 AE 0.80 7.2 AE 0.80 2.8 AE 0.20 1.6 AE 0.09 0.11 AE 0.001 April 2011 7.7 AE 0.40 21 AE 0.36 6.5 AE 0.42 3.9 AE 0.18 1.5 AE 0.05 0.15 AE 0.007 7.5 AE 0.15 21 AE 0.90 6.8 AE 0.25 3.0 AE 0.14 1.5 AE 0.10 0.09 AE 0.012 May 2011 7.4 AE 0.15 22 AE 0.45 7.5 AE 0.41 4.5 AE 0.12 1.6 AE 0.15 0.14 AE 0.006 7.4 AE 0.11 24 AE 0.85 6.7 7.4 AE 0.15 22 AE 0.33 7.8 AE 0.48 3.5 AE 0.10 1.6 AE 0.08 0.15 AE 0.015 7.4 AE 0.14 23 AE 0.45 7.0 AE 0.45 2.8 AE 0.20 1.7 AE 0.04 0.12 AE 0.003 August 2011 7.5 AE 0.30 23 AE 0.46 7.5 AE 0.49 4.1 AE 0.18 1.5 AE 0.12 0.16 AE 0.005 7.5 AE 0.08 25 AE 0.75 6.9 AE 0.75 3.1 AE 0.15 1.5 AE 0.01 0.06 AE 0.006 September 2011 7.6 AE 0.24 21 AE 0.50 7.4 AE 0.42 3.9 AE 0.22 1.6 AE 0.10 0.14 AE 0.008 7.7 AE 0.15 24 AE 0.50 6.5 AE 0.60 3.3 AE 0.12 1.8 AE 0.01 0.07 AE 0.015 October 2011 7.7 AE 0.25 22 AE 0.48 6.7 AE 0.42 3.8 AE 0.20 1.4 AE 0.05 0.14 AE 0.006 7.5 AE 0.12 22 AE 0.85 6.7 AE 0.20 3.2 AE 0.15 1.4 AE 0.02 0.08 AE 0.002 Yenga dam Mauna dam November 2010 7.4 AE 0.15 25 AE 0.55 7.0 AE 0.20 3.5 AE 0.20 0.9 AE 0.01 0.10 AE 0.001 7.6 AE 0.30 24 AE 0.55 5.6 AE 0.45 2.7 AE 0.20 1.1 AE 0.05 0.15 AE 0.004 December 2010 7.3 AE 0.20 26...

In an attempt to describe the benthic macroinvertebrate assemblage of Lake Kenyatta and recommend possible interventions for sustainable management, sampling was done at different stations using an Eckman grab and a scoop net. At each station, six samples were taken (three grabs and three scoops). The samples were washed using a 300µm sieve, sorted live and identified to genus level and where possible to species level using appropriate keys. The specimens were further categorized into functional feeding guilds. The data were then analysed for diversity, evenness, abundance and dominance. Forty two species in 25 families and 13 orders were recorded. The organisms were further grouped into 4 functional feeding groups. The order Pulmonata dominated the macroinvertebrates sampled with 34.3% relative abundance while the lowest were Rhynchobdellida and Lepidoptera with 0.3% each. The high abundance of mollusks in the lake is probably an indication of absence of a predator. It is thus recommended that a fish species be introduced to convert these mollusks into fish biomass. This will enhance the economic gains and reduce the risk of bilhazia infestation since the host snail exists within the lake.

This study is set to investigate the macroinvertebrate community structure within water hyacinth in the Kenyan waters of Lake Victoria. This is helpful in determining the relationship between water hyacinth and macroinvertebrates. A total of four replicates were taken from 18 sampling stations within the lake using a Ponar grab and a 500 µm scoop net. The samples were washed through a 300 µm sieve and sorted alive in the field. The organisms were then identified to genus level and further categorized into functional feeding guilds using available keys and literature. The vertical position of the organisms at a water hyacinth mat was also examined. The data was then analyzed for diversity and abundance. One way ANOVA was further done to test any significant variation in community attributes between stations within the lake. All the physic-chemical parameters measured varied significantly though pairwise comparison revealed that most stations were in same sub set. A total of 14 orders and 34 genera were identified during the study. Out of which, 13 genera which include Chironomus,

The study investigates the effects of Eichhornia crassipes (water hyacinth) infestation based on coliform loads which are pollution indicator organisms. These dams have fish and the waters are commonly used for domestic purposes without any treatment hence it is necessary to check their status. Sampling was done on 25 small water bodies and from which water samples were taken for microbial determination. Membrane filtration method was used to enumerate fecal coliforms by use lauryl sulphate broth and incubated at 44 ± 0.5°C for 18 to 24 h. The results show that water bodies infested by water hyacinth harbored higher levels of fecal coliforms compared to those devoid of the weed. The high fecal coliform levels have negative impacts on the lives of communities using these water bodies. In addition, it reduces native species and disrupts food chains and nutrient cycle. The small water bodies within the Lake Victoria basin need frequent monitoring in order to give the relevant authorities concrete information for proper sensitization to the communities. Water hyacinth should also be properly managed so that it does not chock dams that are used for domestic and fishing activities.