Invertebrate communities in northern Lake Victoria, with reference to their potential for fishery production

The zooplankton and macrobenthic communities of Lake Victoria were sampled by lift net and Ponar grab, respectively. The zooplankton comprised copepods and cladocerans, rotifers and aquatic insect larvae. Most taxa exhibited wide distribution in the lake, with the exception of rotifers which were rare in deep offshore waters. The main components in the macro-benthos were chaoborid and chironomid larvae and molluscs. Caridina nilotica (Roux) and other groups were rare in the samples. Zooplankton density ranged from 100000 or more to 4 million ind. m2 and increased from the shallow inshore to deep offshore waters. Numerical dominance of cyclopoids and nauplius larvae was a common feature at all stations sampled. Most macrobenthic taxa were also widely distributed, although chaoborid and chironomid larvae were rare in the samples. Rastrineobola argentea (Pellegrin) and larval Lates niloticus (L.) ate mainly cyclopoid copepods, while cichlids showed a strong preference for adult insects. High ecological stability of the cyclopoids, and the zooplankton community in general, despite radical ecosystem changes in recent years, coupled with what appears to be high predation pressure, offers good prospects for the pelagic fishery in the lake.

The history of fish communities, biodiversity and environment of Lake Victoria and the lessons learnt

The first fishery survey of Lake Victoria was conducted between 1927 and 1928 (Graham 1929). Atthat time, the lake had a diverse fish fauna and the fishery was dominated by two endemic tilapiine cichlids; Oreochromis esculentus (Graham 1929) and O. variabilis (Boulenger 1906). There were a number of other species such as Protopterus aethiopicus Heckel 1851, Bagrus docmac (Forsk.) 1775, Clarias gariepinus (Burchell), Barbus species, mormyrids, Synodontis spp, Schilbe intermedius (Linn.) 1762 and Rastrineobola argentea Pellegrin, 1904 that were also abundant in the lake most of which made a significant contribution to the fishery (Graham 1929, Worthington 1929, 1932, Kudhongania & Cordone 1974). Haplochromine cichlids were represented by at least 300 species more than 99% of them endemic (Greenwood, 1974; Witte et al., 1992 a & b). The fishery of Lake Victoria was similar to that of lakes Kyoga and Nabugabo (Worthington 1929; Trewavas 1933; Greenwood 1965, 1966; Beadle 1962, 1981). There were also important fisheries on the inflowing rivers of Lake Victoria, the most important of which were Labeo victorianus and Barbus altianalis (Cadwallader 1965). The small sized species notably Rastrineobola argentea and haplochromines cichlids were not originally commercially exploited.

The nutritional status of fishing and non-fishing communities of Lake Victoria basin

We examined socio-economic variables that contribute to malnutrition in selected communities in the Lake Victoria basin during 2001. The study was carried out in nine districts and hinterland communities up to 25 km awayfrom the beach were used as the reference population. The main variables examined were: feeding habits, income and intra-household food distribution and living standards. Others included disease and health, sanitation and hygiene, childcare and mothers' age and workload, weaning practices, agricultural production and food availability, care during pregnancy and food taboos.

Epidemiology of bilharzia (Schistosomiasis) among fishing communities of Lake Victoria

The study was done in six districts of Mukono, Jinja, Iganga, Bugiri, Busia and Kalangala. At both mainland shoreline and islands, 271 adult respondents were randomly selected from 17 landing sites of Lake Victoria over a four months period between October 2000 and January 2001. A questionnaire was administered for symptoms of schistosomiasis and samples of stool, urine and blood were taken from respondents. Stool and urine were analysed for schistosome eggs and blood. Blood was analysed for increased eosinophils. Snail samples were collected from various depths along the shoreline of study sites identified and screened for schistosome cercariae.

Wetlands and riparian zones as buffers and critical habitats for biotic communities in Lake Victoria

Despite their ecological and socio-economic importance, Lake Victoria's adjoining "swamps" and lake interface are among the least investigated parts of the lake. The "swamps" a term commonly equated to "wastelands" and the difficult working environment they present in comparison to open water, are major factors for the low level of attention accorded to shoreline wetlands. Moreover, definitions of wetlands highlighted for example in the Ramsar Convention as "areas of marsh, fern, peatland or water, whether natural or artificial, permanent or temporary, with water that is static or flowing, fresh or brackish, or salt, including areas of marine water, the depth of which does not exceed six metres" (Ramsar, 1971) were designed to protect birds (water fowl) of international importance. The Ramsar definition, which also includes oceans, has till recently been of limited use for Lake Victoria, because itdoes not fully recognise wetlands in relation to other public concerns such as water quality, biodiversity and the tisheries that are of higher socioeconomic priority than waterfowl. Prior to 1992, fishery research on Lake Victoria included studies of inshore shallow habitats of the lake without specific reference to distance or the type of vegetation at the shore. Results of these studies also conveniently relied heavily on trawl and gill net data from the 5-10 m depth zones as the defining boundary of shallow inshore habitats. In Lake Victoria, such a depth range can be at least one kilometre from the lake interface and by the 10m depth contour, habitats are in the sub-littoral range. Findings from these studies could thus not be used to make direct inferences on the then assumed importance of Lake Victoria wetlands in general.

Effects of cage fish culture on water quality and selected biological communities in northern Lake Victoria, Uganda

Growing of fish in cages is currently practiced in Uganda and was first introduced in northern Lake Victoria in 2010. An environment monitoring study was undertaken at Source of the Nile, a private cage fish farm, in Napoleon gulf, northern Lake Victoria. In-situ measurements of key environmental (temperature, dissolved oxygen, pH and conductivity) and biological (algae, zooplankton, macro-benthos) variables were made at three transects: Transect 1- the site with fish cages (WC); transect 2- upstream of the fish cages (USC-control) and Transect 3- downstream of the cages (DSC). Upstream and Downstream sites were located approximately 1.0 km from the fish cages. Environment parameters varied spatially and temporally but were generally within safe ranges for freshwater habitats. Higher concentrations of SRP (0.015-0.112 Mg/L) occurred at USC during February, September and at DSC in November; NO2-N (0.217- 0.042 mg/L) at USC and DSC in February and November; NH4-N (0.0054- 0.065 Mg/L) at WC and DSC in February, May and November. Algal bio-volumes were significantly higher at WC (F (2,780)=4.619; P=0.010). Zooplankton species numbers were consistently lower at WC with a significant difference compared to the control site (P=0.032). Macro-benthos abundance was consistently higher at the site with cages where mollusks and low-oxygen and pollution-tolerant chironomids were the dominant group. Higher algal biomass, concentration of low-oxygen/pollution-tolerant macro-benthos and depressed zooplankton diversity at WC suggested impacts from the fish cages on aquatic biota.

Socio-economic baseline survey of the fishing communities of Lake Victoria, Uganda

The purpose of the Socio-economic Baseline Survey of the Fishing Communities was to provide information on the fish landing beaches, people involved in fisheries, their livelihood activities and facilities available to them.

The socio-economic aspects of the fishing communities of Lake Victoria, Uganda

A baseline survey of the fishing communities was conducted in 2005/06 as one of the main studies under the Socio-economic Research and Monitoring Working Group on Lake Victoria. The overall objective of the survey was to provide a deeper understanding of the broad socio-economic characteristics and well being of the different stakeholder groups immediately dependent on the Lake Victoria fisheries. An understanding of socioeconomic status of the fishery primary stakeholders, who include fishers, artisanal processors and traders, is essential for any subsequent periodic evaluation of development. During the survey, a total of 1,235 respondents were interviewed, at 34 landing sites in all the Ugandan districts on Lake Victoria. The purpose of this fact sheet is to provide information on the fish landing beaches, people involved in fisheries, their livelihood activities and facilities available to them.

Fisheries management in the social domain: perspectives from Tanzania's Lake Victoria fishery

For a long time, the Tanzanian Fisheries Department has managed Tanzanian fisheries without incorporating other stakeholders within its management framework. On lake Victoria, the persistent use of illegal fishing gear and declining catches have led the government to realize that this system of fisheries management may no longer be viable, and have sought to incorporate fishing communities into the management structure. Through the creation of beach management units (BMUs), the Fisheries Departments have sought to persuade fishing communities to implement and enforce Tanzania's fishing regulations and to monitor the fishery. In this paper we explore a recently gathered data set that yields information on, amongst others, how Tanzanian fishing communities perceive the state of their resource base, how they view their relationship with the Fisheries Department, the efficacy of fishing regulations and other variables. We draw on a series of criteria developed by Ostron (1990) for institutional 'robustness' to explore various areas of institutional development on Lake Victoria, and to try and anticipate how the BMUs will fare. We argue there are many socio-political and economic factors that will determine how communities will receive and perceive their responsibilities towards government-imposed administrative structures at the local level, these will become 'socialized' such that they will vary from place to place. While this may bode well for problems of heterogeneity, it does not necessarily mean that fisheries management objective on Lake Victoria will be met

An assessment of co-management potentials in the Lake Victoria fisheries of Kenya

Co-management is a system or a process in which responsibility and authority for the management of common resources is shared between the state, local users of the resources as well as other stakeholders, and where they have the legal authority to administer the resource jointly. Co-management has received increasing attention in recent years as a potential strategy for managing fisheries. This paper presents and discusses results of a survey undertaken in the Kenyan part of Lake Victoria to assess the conditions - behaviour, attitude and characteristics of resource users, as well as community institutions - that can support co-management. It analyses the results of this survey with respect to a series of parameters, identified by Pinkerton (1989), as necessary preconditions for the successful inclusion of communities involvement in resource management. The survey was implemented through a two-stage stratified random sampling technique based on district and beach size strata. A total of 405 fishers, drawn from 25 fish landing beaches, were interviewed using a structured questionnaire. The paper concludes that while Kenya's lake Victoria fishery would appear to qualify for a number of these preconditions, it would appear that it fails to qualify in others. Preconditions in this latter category include the definition of boundaries in fishing grounds, community members' rights to the resource, delegation and legislation of local responsibility and authority. Additional work is required to further elaborate and understand these shortcomings

Lake Victoria Fisheries Management Plan

The purpose of this Fisheries Management Plan (FMP) within the Lake Victoria Fisheries Research Project was to sustain the livelihoods of the communities who depend on the fishery resources of the lake and to reduce poverty, food insecurity and unemployment. To achieve this goals, a better management of the resources, which would mobilize and include stakeholders at local, regional, national and international level was believed to be the right strategy for success. (PDF contains 79 pages)

Socio-economic implications of the fish export trade on the fishers and fisheries of Lake Victoria in Uganda

The purpose of this study was to investigate the implications of the fish export trade on the fishers and the fisheries resources of Lake Victoria, Uganda with respect to sustainability. Eight fish processing factories and ninety fishers were qualitatively investigated. Socio-economic characteristics of fishers and the economic characteristics of fish factories formed a basis for the analysis. Results of the research indicate that there is a relationship between the growth in fish export trade, particularly the growth in industrial fish processing (for export) and declining fisheries resources of the lake. However, whether or not that impact is positive or negative, and to what extent there is an impact, is highly dependent upon the underlying socio-economic considerations of the fishers to the process. The fish-ban imposed by the European Union countries was particularly decried by fishers and factory owners as the main cause for the present poverty among the fishers. Fundamentally, several conflicting issues: ecological, physical and economic activities are a threat to the sustainability of the Lake Victoria fisheries, and for all that depend on and interact with the lake. There is urgent need to address the immediate issue of the growing riparian population and the global fish trade, to educate and train all the relevant actors in appropriate fisheries management techniques. Attitudes of fishers towards the fish factory developments are positive and this is a way forward for co-management for the sustainability of the fisheries resource.

Deleterious effects of non-native species introduced into Lake Victoria, East Africa

Lake Victoria, in East Africa, has suffered from introductions and invasions of non-native species such as Lates niloticus, various tilapiine species, and Eichornia crassipes since the 1950s. These have had a devastating effect on the natural biological communities. This paper reviews the effects of the introductions on ecology, environment, fisheries and the local human population.

Socio-cultural influences on sanitation, fish handling and artisanal fish processing within the fishing communities

The fishery sector in Uganda has seen important changes in the last two decades. Among the changes registered, is the expansion of fish markets locally, regionally and internationally. Upon which, remarkable benefits have been realized at local and national levels, for instance, it is estimated that an average of 40m$ is being earned annually as foreign exchange. Besides, presently fish accounts for over 50% of total animal protein in take. However, it is argued that sustaining these gains has become an up hill task due to failure to maintain fish quality as a result of the rudimentary and inappropriate sanitary, fish handling and artisanal fish processing practices that both directly and indirectly affect the quality of fish and fish products. Therefore, against this background, a study of 507 respondents was undertaken among the Lake Victoria Communities specifically in Wakiso, Mayuge and Mukono districts. The study examined the perceptions of fishers on the social cultural practices of sanitation, fish handling and artisanal fish processing and consequently identified factors that influenced these practices.

Environment monitoring technical report for the SON cage fish culture site at Bugungu, Napoleon Gulf, northern Lake Victoria, June 2013

Source of the Nile Fish farm (SON) is located at Bugungu area in Napoleon Gulf, northern Lake Victoria. The proprietors of the farm requested NaFIRRI to provide technical assistance to undertake regular environment monitoring of the cage site as a mandatory requirement under the NEMA conditions. NAFIRRI agreed to undertake regular environment surveys in the cage area covering selected physical‐chemical factors (water column depth, water transparency, water column temperature, dissolved oxygen, pH, conductivity, nutrient status), algal aquatic invertebrates (micro‐invertebrates/zooplankton and macro‐benthos) and fish communities. During the year 2013, it was agreed with management to undertake quarterly environment monitoring surveys. However, the first quarter (January‐March 2013) survey was missed out due to late decision. The present report therefore covers the survey taken during the second quarter (April‐June 2013). Results/observations made are presented in this technical report along with a scientific interpretation and discussion of the results with reference to possible impacts of the cage facilities to the water environment and aquatic biota.