The biology, ecology, distribution and conservation of surviving haplochromine cichlids in Lakes Victoria, Kyoga and Nabugabo

Haplochrmine cichlids were the most abundant taxa in Lakes Victoria, Kyoga and Nabugabo prior to introduction of the Nile perch. As stocks of the introduced predator increased, these taxa were depleted to such an extent that they are now virtually absent from the lake. The haplochromine cichlids played an important role in the ecology of Lakes Victoria, Kyoga and Nabugabo. They occupied virtually all trophic levels in the lake and facilitated an efficient flow of energy through the ecosystem. Their depletion seem to have left much organic matter whose decomposition has contributed to accumulation of dead organic matter which may be contributing to prolonged anoxia in Lake Victoria. The haplochromines formed an important small-scale fishery. Fishermen formerly subsisting on this fishery have been driven out of business because they cannot afford the expensive nets required for Nile perch fishery. In addition to providing a cheap source of fish protein to humans, the species were an important source of Scientific material for students of genetics antd adaptive radiation.

The impact of fishing gears and methods: with recommendations for management of the fisheries of Lakes Victoria, Kyoga and Nabugabo

Historical analysis has shown that use of destructive fishing gears and methods contributed much to the initial depletion of fish stocks from Lakes Victoria and Kyoga. From about 1930 to 1960, the fisheries of Lake Victoria were managed by controlling the mesh size of gill nets. Gill net s of less than 127 mm (5) stretched mesh had been prohibited on Lake Victoria because they cropped immature Oreochromis esculentus (Ngege) which were at that time the most important commercial species. When the mesh size restriction was repealed in the Ugandan, Tanzanian and Kenya, there was a shift to smaller meshes which cropped immature tilapia and other large species and led to a collapse in the fishery.

Economic impacts of globalisation at the district, landing site and sub-sector enterprise levels on Lakes Kyoga, Albert and Victoria

The Globalisation and fish utilisation and marketing study is a collaboration between the Fisheries Resources Research Institute (FIRRI) and the Mike Dillon Associates Limited , with funding from the Department for International Development (DFID) of the Government of the United Kingdom. The study is designed to examine the impact of the development of the export fishery on the fish producers, processors, traders and consumers in the artisanal fishery in Uganda. FIRRI 's role is to collect field data relating to the livelihoods of artisanal fish producers, processors, traders and consumers. in particular data relating to income and revenue flow. The initial focus is on the eccnomic structure of fish landing sites. The purpose of this paper is to review the progress in implementation of the project and present the interim findings for discussion. During the first quarter, namely April to June, 2002, work was carried out on Lakes Kyoga and Albert and a report produced. During the second quarter, July to September, 2002, Lake Victoria was covered. In both phases, the focus has been on the economic structure of fish landings.

The water hyacinth problem and the biological control option in the highland lake region of the upper Nile basin: Uganda's experience

The rapid proliferation and extensive spread of water hyacinth Eichhornia crassipes (Mart) Solms in the highland lakes of the Nile Basin within less than 15 years of introduction into the basin in the 1980s pauses potential environmental and social economic menace if the noxious weed is not controlled soon. The water weed has spread all round Lake Victoria and, in Uganda where infes tation is mos t severe, water hyacinth estimated at 1,330,000 ton smothers over 2,000 ha of the lakeshore (August,1994). Lake Kyoga which already constantly supplies River Nile with the weed is infested with over 570 ha, while over 80% of the river course in Uganda is fringed on either side with an average width of about 5m of water hyacinth. As the impact of infestation with water hyacinth on water quality and availability, transportation by water, fishing activities, fisheries ecology, hydro-power generation etc becomes clear in Uganda, serious discussion is under way on how to control and manage the noxious weed. This paper pauses some of the questions being asked regarding the possible application of mechanical and chemical means to control the water weed.Uganda has already initiated the use of biological control of water hyacinth on Lake Kyoga with a strategy to use two weevils namely Neochetinabruchi and Neochetina eichhorniae. The strategy to build capacity and infrastructure for mass multiplication and deployment of biological control of the weevils in the field developed in Uganda by the Fisheries Research Insti tu te (FIRI) and the Namulonge Agricultural and Animal production Research Insti tute (NAARI) is proposed in outline for evaluation. Plans to deploy this strategy on lake Kyoga are under way

A study of Rastrineobola argentea in the Ugandan lakes

Increased stocks of mukene Rastrineobola argentea and the subsequent interest in its fishery on Lake Victoria has been attributed to the poor performance of the endemic fishery as a result of introductions into this lake of foreign fish species Lates niloticus and Oreochromis niloticus. R. argentea now remains the only endemic fish species of economic importance ranking second to the Nile perch in this lake. Despite this importance, biological information on the species and knowledge of its fishery is scanty. Preliminary observations on the species in the Ugandan waters indicate that R. argentea feeds mainly on zooplankton (copepods) during daylight hours. Small quantities of aquatic insect larvae/pupae (chironomids and chaoborids) are also eaten mainly at night. These fishes breed just after the rainy seasons and the young eventually mature at between 43-44 mm standard length. Growth and population parameters show a rate of growth (K) of 0.92 with L of 64.5 mm S.L. Natural mortality (M) is given at 2.371 and total mortality (2) of 3.594. Two mesh size nets 10 and 5 mm are in use in the lake. The smaller mesh size which is more preferred by the artisanal fishermen however tends to capture many immature fishes. There is therefore need for a unified lakewide data collection on the species and its fishery in order to obtain more reliable biological information necessary proper management of this fast developing fishery.

A study of Rastrineobola argentea (Pellegrin), (Pisces : Cyprinidae) and its importance in the fisheries of Lake Kyoga and the northern waters of Lake Victoria

Rastrineobola argentea is the only native fish species which is still abundant in Lakes Victoria and Kyoga, the others being two introduced species; Lates niloticus and Oreochromis niloticus. It forms an important commercial fishery in Lake Victoria and is very important as food of Lates niloticus in both lakes. The depletion of the originally abundant insectivorous and zooplanktivorous hap lochromines due to predation by Lates niloticus appears to have favoured it by reducing potential competitors for food. It now consumes a wide range of invertebrate organisms that originally used to be eaten by different specialised species of haplochromines which include: larvae and pupae of chironomids and chaoborids, copepods and ostracods. Its size in Lake Kyoga (where the Nile perch was introduced earlier) has, however, decreased and is smaller than that in Lake Victoria probably due to high predation pressure. The twin effect of predation and fishing are likely to exert heavy pressure on the species. Research is therefore required to provide information for its management.

Trolling for Nile perch (Lates niloticus) in Lake Kyoga

Nile perch were introduced into Lake Kyoga in the mid·1950s from Lake Albert. Murchison Falls on the River Nile, between the two lakes, prevented Nile Perch and other elements of the typical nilotic fish population from naturally reaching Lake Kyoga. The introduction has been successful and considerable stocks of Nile Perch now exist in Lake Kyoga. In 1967, 13,000 tons of Nile Perch were estimated to have been landed by the commercial fishermen, fish of 200 lb. being now caught and specimens of 100 lb. being fairly common. Large Nile perch are caught commercially on long lines baited with live Protopterus' spp. or Clarias spp. Large mesh gillnets uccasionally take Nile Perch of up to 30 lb., but the high cost of the nets does not, at the moment, appear to justify this method of fishing; a 10 in. net, stretched 100 yards long (unmounted). 15 meshes deep and 60-ply nylon. costs approximately U. Shs. 300. The long·lines used are extremely simple and cheap to make, but considerable labour is needed to catch bait. Small Protopterus are normally caught by turning over floating rafts of grasses and papyrus, and extracting the fish from the root mass; this is hard and dirty work. Other small fish, more readily available, do not, according to fishermen, work as well, possibly because they are not as durable as the Protopterus or Clarias. Dead bait is never used.

Increase in fish production achieved by stocking exotic species (Lake Kyoga, Uganda)

The Lake Kyoga complex lies towards the north of Uganda, at 311 altitude of 3,400 feet, between 10 and 2° north of the Equator. The lake is extremely elongate and digitate, shallow (1 metre-7 metres), and almost all the coast-line is swampy, with many papyrus beds. Floating islands of sud are a feature. At its eastern extremity, it breaks up into many swampy, isolated lakes. The Nile from its source at Jinja enters Lake Kyoga on its southern side, and leaves the lake at its western extremity, and winds on through to Lake Albert and the Sudan. The Kyoga/Salisbury /Kwania complex covers 2,354 sq. km. of water. Geologically, the lake is a series of flooded river valleys, probably resulting from the uplifting of the western edge of the basin in the Pliocene and the Pleistocene ages aud the endemic fish fauna is very similar to that of Lake Victoria, although Kyoga has not developed the species flocks of haplochromis which characterise the larger lake. The Victoria fauna extends down-stream of Lake Kyoga to the Murchison Falls on the Nile, which forms an almost complete barrier between Kyoga and the typical nilotic fauna of the Nile below Murchison and Lake Albert.

The Nile perch in Lakes Victoria and Kyoga: an asset or liability?

Combined effects of lack of firm and effective management measures for years, over exploitation with destructive fishing gears and interspecific competition, particularly among tilapiines and profound effects on the fish stocks of Lake Victoria and Kyoga. It has been proposed that these have been more important in the decline of the indigenous fisheries than predation or competition by Nile perch.

Report on Lake Wamala fisheries catch assessment survey 2012

Lake Wamala is one of the small lakes in Uganda, and lies between latitudes 0o 15; and 0o 25' N 31o 45' to longitude 32o 00' E, longitude and at an altitude of 1000m above sea level. Following ths 1961 heavy rains the lake expanded from about 100 to 118 sq. km and the swamps covered almost 60 sq km (Okaranon 1993). This lake was first stocked with Oreohromis niloticus eduardianus populary known as Oreohromis niloticus then Oreochromis leucostictus and then Tilapia zillii then after that it was officially opened for commercial fishing in 1960. Despite of the commercial fishery there used to be subsistance fishing that was mainly by the use of wires and hooks and targeted the Clarias and Protopterus species. The lake fishery used to be highly profitable after the opening in 1960; though in 1970s the fishers started complaining of the declining state of the fishery. At that time the O. niloticus had gone down to less than 1 kg per net per night by 1975 (Okaranon 1993). Due to it led to scientists undertake fisheries surveys in 1975/78 and later 1988/92 then later on there subsquent survey in 2003. Since that time there has been no work done until March 2012 that both catch assessment and frame surveys undertaken to ensure that management issues are addressed concerning this riparian water body. The main objectives of the survey were:- To assess fish production levels in the commercial fisheries of Lake Wamala (Catch Assessment). To assess the fishing effort and facilities available at the fish landings that supports the fisher folks.

Report of Lake Wamala fisheries frame survey 2012

Lake Wamala, a small lake (180 km2) located in Central Uganda and believed to have been part of the main Lake Victoria and only got separated about 4000 years ago, has already undergone different levels of fisheries evolution that warrant using it as a case study to inform changes in other systems. Using resources provided by the Lake Victoria Environmental Management Project (LVEMP) II, under the Applied Research Facility, we evaluated the fishing inputs, socio-economic infrastructure and analyzed trends in fishery benefits to guide evolution of management advice. A frame survey was conducted on the entire lake (13th - 23rd March 2012) enumerating all fishing factors and enlisting available and accessible socio-economic infrastructure along the shores of the lake. The lake traverses districts (Gomba, Mityana, and Mubende) with its largest portion lying in Mityana. There are 26 established fish landing sites and about 600 fishers with a similar number of boats on the lake. The total number of boats on the lake is almost equal to the number of fishers; illustrating the common type (paracute) and size (Small, about 4 m) of boats and hence a fishing crew structure of one fisher per boat. Main fishing gears are Gillnets targeting the tilapia (Ngege) and long line hooks (Protperus, Mamba, and Clarias, Male). Almost equal number of boats used the two main gears on the lake (about 300 each). 97% of the gill nets on the lake are small (3.5” (8.9 cm – 4.5” – 11.4 cm) stretched mesh size while 98% of the hoots are large (< size 10). The implication is gill net fishers target small tilapia while long line fishers aim at the large mamba and male. Generally the lake has poor socio-economic infrastructure compared to other lakes of Uganda probably due to its geo-morphological setting. The lakes fishing factors have continued to expand with the ever increasing population. There may be need to check the continued entry into the fisheries especially if the increasing effort does not translate into increase in fishery yield.

Report of frame survey of the Kyoga basin lakes 2008

A comprehensive Frame survey was carried out on lakes Kwania, Bisina, Nakuwa, Kyoga and other minor lakes in the Lake Kyoga Basin in June 2008 (Figure 1). The Frame survey was coordinated by the Department of Fisheries Resources (DFR) in collaboration with the National Fisheries Resources Research Institute (NaFIRRI) in terms of technical support. The riparian districts through the sub-county fisheries offices and the BMUs provided the enumerators and supervisors. The frame survey captured all the important characteristics of the fisheries and facilities supporting the fisheries and thus provides a strong baseline for future reference of management interventions in the basin.

Issues of HIV/AIDS/ health among the fisher communities of Lake Albert and Kyoga

The fisheries resources of Lakes Albert and Kyoga present a high potential for economic growth, food, employment and foreign earnings. However, livelihoods appear to be compromised with the emergence and rapid spread of HIV/AIDS in the fisher communities of L. Albert and Kyoga. HIV/AIDS is considered a silent epidemic that is unique, posing a great challenge to the fisheries managers, health service providers, development planners and the resource users themselves. Fishers have high HIV prevalence, as well as AIDS-related illnesses and mortality rates. The high HIV prevalence rates among the fishing communities in Uganda is between 10-40% compared to the national rates which lie between 6% and 7%. This indicates that the national programmes have not adequately addressed the plight of the fishing communities of Lakes Albert, and Kyoga and the consequences have been devastating. Men and women living in fishing villages across the world have been found to be between five and ten times more vulnerable to the disease than other communities (Tarzan et al 2005, FAO, 2007). The present prevalence rates among the fishing communities stands at 10 to 40 % (LVFO, 2008). Meanwhile the same fishing communities are the essential labour for the Lakes’ fishery industry which is thriving nationally and internationally. That resource potentially can alleviate poverty and the HIV/AIDS threat. Fishing communities are the hidden victims of the disease, mixing patterns with the general population could act as a reservoir of infection that could spill over into the general population to drive the epidemic. On L. Albert, a quarter of the fisher folk were HIV-positive by 1992 compared to 4% in a nearby Agricultural village. Since then, there have been no targeted studies to address or monitor the prevalence rates eight years later, yet the multiplicity factor is high. HIV/AIDS can be linked to unsustainable fisheries, as the labour force available would not go to deep waters to fish, instead would fish in the shallow waters as a coping mechanism. A further effect is the loss to National and local economies and reduced nutritional security for the wider population. HIV/AIDS remains a significant challenge that has created a mosaic of complexity in the fishery sector. This needs to be addressed. It is, therefore, paramount that a comprehensive study was under taken to address this pandemic and the phenomenon of HIV/AIDS based on the study objectives. 1. To determine the trend in HIV/AIDS infection among fishing communities and the factors affecting it 2. To assess the impacts of HIV/AIDS on fish production and the implications for fisheries management.

An instance of cyclonic upwelling in the southern offshore waters of Lake Victoria

Evidence is presented that cyclonic upwelling took place in the southern offshore waters of Lake Victoria on the 22nd to the 23rd March, 1969. Before this, the main upper thermocline was tilted downwards in the leeward northern half of the lake in response to the accumulation of epilimnetic water. Cyclonic upwelling might be quite common because of the frequent occurrence of storms on Lake Victoria, and probably on other tropical African lakes. However, to my knowledge, it has never been reported from any lake.

The ADP/FS frame survey of Lake Kyoga and Lake Kwania

The report provides a summary of the frame survey results carried out in lakes Kyoga and Kwania in 1990. The ADP Fisheries Survey of Lake Kyoga is charged with a stock-assessment programme. The term stock-assessment is generally used to express the need of fisheries managers for knowledge on fish stocks which are allegedly over-exploited already. Stock-assessment can be very comprehensive, costly and time-consuming. Essentially however, investigations into exploited stocks and the fishery should provide viable answers to the questions of management at the shortest possible notice. Surveys should in any case provide indications concerning the rate of exploitation. That requires the execution of a catch assessment survey (CAS).