Socio-economics of fishing communities on Uganda water bodies

Control and management of Uganda fishery resources has been hindered by among other factors the multispecies nature of the resource and the characteristic behaviour of the fishing communities. Fishermen have both genuine and uncompromising attitudes as to why they carry out certain fishing technologies.All fishing activities aim at maximizing the catches or profits while others may fish on a small scale for subsistence. Sensitizing the fisherfolk on the appropriate fishing technologies, importance of a well regulated fishery exploitation and their participation in control and management of the resource would enhance or lead to increased and sustainable fish production. Socio-economics of fishing technologies were therefore examined using prepared questionnaires and reasons why the fishing communities behave the way they do established

Invertebrate communities of Lake Nabisojjo

Invertebrates are organisms without a backbone on the basis of body size. Aquatic invertebrates can be divided into two broad categories: micro-and macro-invertebrates. The former commonly known as zooplankton, ranging in size from < 100um 10 ca.1500um and are mainly planktonic (i.e living suspended in the water column). The latter, also known as benthos, (bottom dwelling) are associated with bottom sediments(ie, living on sediment surface or burrowing in sediments), are much bigger organism greater than 1500um in body size.

Report on the frame survey of Lake Albert conducted in May 2012

Lake Albert and Albert Nile are a major source of fisheries resources sustaining the riparian communities in Uganda and the Democratic Republic of Congo (DRC). Like all shared bodies of Uganda Lake Albert and Albert Nile fisheries are faced with immense exploitation pressure one time described as the tragedy of the commons. In Uganda, the lake is shared by five riparian districts namely: Buliisa, bundibugyo, Hoima, Kibaale and Nebbi. The lake covers a total estimated surface area of 5,270 km2 with approximately 60% within Ugandan waters (Walker, 1972). It is located in the western part of the great rift-valley at an altitude of 618 m above Sea level. The central parts of the lake are characterized by steep escarpments whereas the northern and southern parts lie in a plain of the rift valley. The plains are gently sloping, resulting in shallow swampy inshore waters in many places. The major inflowing rivers are the Semliki and Kafu in the south, and the Victoria Nile at the northern tip. The lake has a diverse fish fauna with a gradient of multi-species fisheries in different parts of the lake.

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.

The role of satellite lakes in conservation of fish species diversity in the Lake Kyoga basin

Lakes Victoria and Kyoga had, a diverse fish fauna, which was important as food for local population and valuable in scientific studies. Over the past twenty years, the diversity of fish in these lakes had declined due to over-exploitation, introduction of new fish species including the piscivorous Nile perch and degradation of fish habitat. Studies of satellite lakes in the Victoria and Kyoga lake basins suggested that some of these lakes harboured species which had been lost from the main lakes. In order to better understand the extent, to which these satellite lakes may serve as refugia, a faunal survey was undertaken to determine the distribution and nature of the taxa found. Seven satellite lakes and the eastern end of the main Lake Kyoga adjacent to these minor lakes were surveyed over a two-year period for fish species diversity. A total of 68 fish species were recorded of which 41 were haplochromines. Almost all the native non cichlids which occurred in the main lakes (Victoria and Kyoga) before the Nile perch upsurge recorded. Lakes Nawampasa, Gigati, Kawi, Agu and Nyaguo had the highest fish species and trophic diversity. The trophic diversity of haplochromines (based on Shannon Weaver Index) was highest in Lake Nawampasa (1.28), followed by Gigati (1.25), Kawi (1.18), Agu (0.8), Lemwa (0.81), Nyaguo (0.35) and was lowest in the main Lake Kyoga. Potential threats to these lakes were from collectors of ornamental fish species, especially the haplochromines, the spread of the predatory Nile perch and the water hyacinth, which are already in Lake Kyoga, and the destruction of macrophytes through harvesting of papyrus and reclamation for agriculture. The human population around these lakes harvested the fishes for food but the levels of exploitation were still low because the lakes were adjacent to main Lake Kyoga, the major supply of fish. Ornamental fish dealers were encouraged to start captive breeding of the fish for export to reduce pressure on the lakes and demonstrations for breeding were set up at FIRI in Jinja. Meetings and seminars were held with some of the communities living around the lakes sampled and the importance of fish species found in these lakes and the dangers of destructive practices discussed. Representatives of all taxa of fish caught from the lakes were preserved, catalogued and stored in the FIRI Museum. Results from this survey support the motion that these satellite lakes are important refugia for endemic diversity. Based on survey, we recommend that SaIne of these lakes like Nawampasa, Gigati, Kawi, Agu and Nyaguo could be designated as conservation areas of species threatened in the main lakes. One of the factors that seem to have prevented the spread of Nile perch into Kyoga Minor lakes seems to have been the presence of extensive swamps around these lakes and the low oxygen levels that exist in these habitats. Clearing of swamps and vegetation that separate Kyoga minor lakes from the main lake should be avoided to prevent Nile perch from spreading into these lakes.

Knowledge, perceptions, impacts and roles of lakeside communities and institutions in the sustainable control of water hyacinth

The massive water hyacinth mats that covered water bodies in the 1990s had serious social and economic impacts. They affected fishing, transportation, water quality and health of fishing communities as well as production of goods and services of lake-based institutions (commercial establishments). At peak infestations, the communities and institutions were aware of and participated readily in control effort. However, after the major collapse of hyacinth in 1998, some of them relaxed in their control efforts. The status of knowledge, perception, impacts, preparedness and role of the lakeside communities and institutions to control the weed has, therefore, been monitored since the major resurgence of the weed to find out if the lakeside communities and institutions still perceive water hyacinth as a problem and the extent to which they are prepared to sustain control.

Diverse 3D microarchitectures made by capillary forming of carbon nanotubes.

A new technology called capillary forming enables transformation of vertically aligned nanoscale filaments into complex three-dimensional microarchitectures. We demonstrate capillary forming of carbon nanotubes into diverse forms having intricate bends, twists, and multidirectional textures. In addition to their novel geometries, these structures have mechanical stiffness exceeding that of microfabrication polymers, and can be used as masters for replica molding

PCR-DGGE Fingerprinting Analysis of Plankton Communities and Its Relationship to Lake Trophic Status

Plankton communities in eight lakes of different trophic status near Yangtze, China were characterized by using denatured gradient gel electrophoresis (DGGE). Various water quality parameters were also measured at each collection site. Following extraction of DNA from plankton communities, 16S rRNA and 18S rRNA genes were amplified with specific primers for prokaryotes and eukaryotes, respectively; DNA profiles were developed by DGGE. The plankton community of each lake had its own distinct DNA profile. The total number of bands identified at 34 sampling stations ranged from 37 to 111. Both prokaryotes and eukaryotes displayed complex fingerprints composed of a large number of bands: 16 to 59 bands were obtained with the prokaryotic primer set; 21 to 52 bands for the eukaryotic primer set. The DGGE-patterns were analyzed in relation to water quality parameters by canonical correspondence analysis (CCA). Temperature, pH, alkalinity, and the concentration of COD, TP and TN were strongly correlated with the DGGE patterns. The parameters that demonstrated a strong correlation to the DGGE fingerprints of the plankton community differed among lakes, suggesting that differences in the DGGE fingerprints were due mainly to lake trophic status. Results of the present study suggest that PCR-DGGE fingerprinting is an effective and precise method of identifying changes to plankton community composition, and therefore could be a useful ecological tool for monitoring the response of aquatic ecosystems to environmental perturbations.

Characteristics of the microbial communities in the integrated vertical-flow constructed wetlands

Microorganisms play an important role in removing pollutants from constructed wetlands. We investigated the microbial characteristics in a novel integrated vertical-flow constructed wetland (IVCW), which has been in operation in Wuhan, China since 1998. We used phospholipid fatty acid (PLFA) and amoA gene to analyze the structure and diversity of the microbial community within the IVCW. PLFA results suggested that the amount of bacterial PLFA was significantly higher than that of fungal PLFA, but the total microbial biomass represented by PLFA index was low in the system. Microbial spatial distribution showed significantly higher bacterial (both G(+) and G(-)) and fungal biomass in the surface than in the subsurface layers. The ratios of monounsaturated to branched PLFA demonstrated that an anaerobic layer sandwiched by two aerobic layers existed in the IVCW, consistent with the redox potential results. Analysis of the amoA revealed the presence of Nitrosomonas-like sequences in the surface substrate of the downflow chamber and apparent diversities of ammonia-oxidizing bacteria in the system. These results suggest that microorganisms, despite their relatively low biomass, have inhabited the IVCW, and the results will offer some valuable information on microbe to system designers and managers.

Speciation and Phylogeography of Opsariichthys bidens (Pisces: Cypriniformes: Cyprinidae) in China: Analysis of the Cytochrome b Gene of mtDNA from Diverse Populations

Gao-Yan Li, Xu-Zhen Wang, Ya-Hui Zhao, Jie Zhang, Chun-Guang Zhang, and Shun-Ping He (2009) Speciation and phylogeography of Opsariichthys bidens (Pisces: Cypriniformes: Cyprinidae) in China: analysis of the cytochrome b gene of mtDNA from diverse populations. Zoological Studies 48(4): 569-583. The cyprinid fish Opsariichthys bidens Gunther is distributed in all major river systems of continental East Asia, and represents an attractive model for phylogeographic studies among cyprinid species or within a given species. In this study, we investigated the phylogeographic and demographic history of this species, using partial sequences of the cytochrome (cyt) b gene in mitochondrial (mt)DNA. Fish samples were collected from almost all major river systems where O. bidens is distributed in China. Sequence analysis showed remarkably high polymorphism, with 125 haplotypes in the 234 specimens examined, and with 89.8% of haplotypes occurring in only 1 specimen. A neutrality test indicated that some groups were not at mutation-drift equilibrium, suggesting a past population expansion. These results were supported by a mismatch distribution analysis. Based on our analysis, O. bidens consists of 4 groups belonging to 2 clades. The divergence time of the 2 clades was estimated to be 11.06-8.04 my. This value corresponds to the time of the 2nd uplift of the Qinghai-Tibet Plateau, the emergence of the East Asian monsoon, and the Epoch-6 Event. A two species scheme is proposed. http://zoolstud.sinica.edu.tw/Journals/48.4/569.pdf