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The objective of this scoping review is to understand the state of existing evidence exploring the relationship between climate change, associated changes in resource availability, transactional sex, and HIV incidence and prevalence, within fishing communities in the Lake Victoria basin.

Global fish oil production is between 1 to 1.25 million tones and primarily exploiting fatty fish such as menhaden, herring, pilchards, anchovy, and sardine among others. The main producing countries include Japan, USA, Chile and Peru. Yet, fish oil from developing countries end up as bio waste since only the flesh is utilized. This paper discusses a simple approach for utilizing the fish bio waste to produce oil andhow the oil quality and quantityis impacted by the extraction process. The visceral organs were collected from fish filleting factory and markets in Kisumu town and oil extracted by modified wet pressing method adopted from Blight and Dyer (1959). The effect of temperature and serial washing on the oil quality and quantity was assessed from extraction temperatures at800C, 900C, 950C and 970C, while employing three serial washing using distilled water and pineapple juice. The quality of the oil produced was then determined based on the proportion of omega -3, vitamin A and E, peroxide value, iodine value and free fatty acids. Statistical analysis was conducted using R-data analysis software at P

Lake Victoria just like many other lakes is affected by water hyacinth which resides in several bays for the better part of the year. This weed affects several economic activities of the locals and denies the government revenue every year from blue economic activities related to the lake. This paper explores the interaction of water hyacinth with biotic and abiotic factor and the efficiency of the introduced weevils in its control with an aim of advising on the best way to tackle the menace of the weed. Water quality samples were collected and compared from the time of water hyacinth arrival and sinking within Winam gulf. Water hyacinth was collected and damages resulting from the weevils as well as the number of weevils recorded. Fish samples were also collected using experimental gill nets. Water quality was analyzed for Ammonium, Soluble Reactive Phosphorus, Nitrates and Nitrates. Data was then analyzed using R- package. Results indicated that the weevils inhibits nutrient uptake by17% within the first four weeks, hyacinth increase the nutrient levels in the gulf almost three fold after decaying and sinking. Weevils also increased the sinking rate of water hyacinth through destruction of the petioles and leaves. There was a significantly higher fish numbers during the weed infestation than when the weed was absent. In conclusion water hyacinth impacts both biotic and abiotic factor and the weevils alone cannot be depended upon to eradicate the weed.

Lake Victoria is of immense ecological and socio-economic significance for the riparian communities. However, the lake is faced with human induced pressures such as overfishing, introduction of alien species, increased eutrophication and climate change impacts. Its large spatial extent and complex ecology have also limited the understanding of the system dynamics, major processes, drivers and responses. To address this challenge, Atlantis, the first end-to-end whole ecosystem model for the lake was developed. First, a Regional Oceanographic Model System (ROMS) for the lake was developed to provide hydrodynamic forcing data for the ecosystem model. The ROMS model was based on real bathymetry, river runoff and atmospheric forcing data. Results from this model revealed diverse spatial and temporal water circulation patterns and temperature trends in Lake Victoria. The ROMS output provided water currents and temperature forcing data for the Atlantis model. The Lake Victoria Atlantis model was spatially resolved into 12 unique dynamic areas based mainly on their biophysical attributes. A total of 38 functional groups constituted the biological model while fishing was implemented by four fleets with different targeting options. The model was validated by fitting simulated output to available observational data sets. Simulations showed elevated nutrients and primary production in inshore areas and gulfs that can be linked to point sources of pollution and limited flushing. The model also revealed complex inter-specific relationships among the biological groups. For example, the introduced Nile perch (\emph{Lates niloticus}) exhibited a strong negative correlation with haplochromine cichlids (their prey) as well as most of other fish groups. This brings to fore the significance of predator-prey relationships and the impact of introduced species; information that is critical for effective fisheries and ecosystem management. The model was then used to simulate the impact of different fishing scenarios on the ecosystem. Scenarios tested included varied fishing pressure for Nile perch (the main predator at the top of the food chain), key prey species (haplochromines) and other species. The effects of these scenarios were tested using six common ecosystem-level indicators. Predictions showed that no particular scenario excels in all the six indicators. However, halting harvesting of haplochromines results in the best overall ecosystem performance. This scenario is projected to result in the highest yield of commercially important species and possibly cause minimal disruption to fishing activities. Findings of this study reinforce the need for an ecosystem approach to fisheries management in Lake Victoria., Viktoríuvatn er mikilvægt strandbyggjum sínum, vistfræðilega, félagslega og efnahagslega. Talsvert álag er á vistkerfið sakir ofveiði, innleiðingar framandi tegunda, mengunar og loftlagsbreytinga. Breytingar af þeim sökum, auk flókinnar vistfræði, hafa takmarkað möguleika á skilning á kerfinu sjálfu, helstu ferlum, áhrifavöldum og viðbrögð kerfisins við breytingum. Til að mæta þessari áskorun hefur heildstætt vistkerfislíkan (Atlantis) verið þróað fyrir vatnið. Sérstakt straumalíkan var þróað fyrir vatnið til að setja upp straumkerfi gögn fyrir vistkerfislíkanið. Straumalíkanið var byggt á upplýsingum um dýpi, rennsli áa ásamt upplýsingum um loftþrýsting og úrkomu. Straumkerfislíkanið sýndi hringrás vatns og þróun hitastigs í vatninu. Atlantis líkanið fyrir Viktoríuvatn inniheldur 12 svæði, byggt á líf- og eðlisfræðilegum eiginleikum. Notast var við 38 hópa lífvera og fjóra veiðiflota með ólíkt valmynstur. Líkanið var mátað við ýmis fyrirliggjandi gögn. Útreikningar sýna aukið magn næringarefna og frumframleiðslu, bæði á grunnslóð og dýpi, sem tengist þekktum uppsprettum mengunar og takmörkuðu gegnumstreymi. Í líkaninu komu einnig fram flókin tiltekin tengsl milli líffræðilegra hópa. Þannig sýndi Nílarkarfi sterka neikvæða fylgni við bráð (haplochromines) og raunar flesta hópa fiska. Þetta sýnir vel mikilvægi samspils afræningja og bráða auk áhrifa innfluttra tegunda og nauðsyn þess að líta á allt vistkerfið þegar v stjórna skal veiðum. Líkanið var síðan notað til að prófa áhrif mismunandi veiðistjórnunar á lífríkið. Sviðsmyndir voru m.a. breytilegt veiðiálag á Nílarkarfa (ránfiskur og efstur í fæðukeðjunni), lykilbráð (haplochromines) og aðrar tegundir. Áhrif sviðsmyndanna voru metin með sex algengum mælikvörðum. Niðurstöðurnar bentu ekki til þess að nein stjórnunaraðferðanna bæri af í öllum sex mælikvörðunum. Prófanir sýna hins vegar að sú aðferð að stöðva veiðar á helstu bráð gefi bestan almennan árangur. Hér fæst mestur afli úr efnahagslega mikilvægum stofnum og lágmarks röskun á veiðum. Niðurstöður rannsóknarinnar sýna vel þörfina fyrir vistkerfisnálgun við stjórnun fiskveiða í Viktoríuvatni., United Nation University - Fisheries Training Programme