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The proliferation of cages in the Great Lakes of Africa is accompanied by the potential socio-economic outcomes which underscores a significant trend in the aquaculture industry that is supplementing the traditional fisheries production. In light of these considerations, the study herein was undertaken to comprehensively evaluate the potential impacts of high intensity of cages at a site in Lake Victoria, Kenya with the leading numerical focus. Anyanga Beach has consistently registered the highest number of cages, making it a focal point for assessing the broader implications of cage aquaculture in the region. The survey exclusively targeted cage aquaculture farmers with the use of structured three-part questionnaires involving the particulars of cages, socio-demographic features and farm operations and investments. Majority of the cages surveyed were found to be locally fabricated, accounting for 93.3% (n = 28), with the main materials used for constructing cage frames being metallic. The use of locally sourced and fabricated materials may indicate a practical approach motivated by considerations such as ease of accessibility, cost-effectiveness and locally-sourced knowledge. Most of the cage aquaculture farmers reported managing between 1 to 6 cages (n = 20; 66.7%), with the most common dimensions being small-sized measuring 2.5 m × 2.5 m × 2 m, suggesting the need to create cohorts of firms that could lead to the development of cooperatives and ease the implementation of regulatory frameworks. Fish escapees from the cages were also reported, with approximately 60% of respondents indicating that they had experienced such incidents. Such occurrences pose a significant risk, which may result in genetic disruption and adversely impacting the overall fisheries. The study recommends for the need to enhance awareness and engagement with key institutions to foster a more informed and compliant approach, while ensuring that practice of cage culture intensification is alig

The extent of flooding in vulnerable inland and lacustrine systems can demonstrate the coverage and the magnitude of such phenomenon for policy enhancement. This study examined the extent of flooding due to rising water levels in selected Afrotropical lakes to guide interventions that would sustain the livelihoods of communities affected. The years that were most prone to flooding (2010 and 2020) were used as a baseline in the extraction of changes in spatial extent and area of lacustrine shoreline, and rainfall and satellite altimetry data, using geospatial and remote sensing technologies. The extent of flooding was strongly but insignificantly related (R2 = 0.63; p = 0.07) to the sizes of the studied lakes and the amount of rainfall. Lakes with the smallest surface areas such as Baringo and Naivasha showed the greatest increase in flooding of 52.63% and 42.62%, respectively. Larger lakes such as Lakes Victoria (1.05%), Turkana (3.77%), and Tanganyika (0.07%) had the lowest increases in areal extent. Furthermore, the topography of the lakes studied further determined the residence time and the extent of flooding, such that lakes such as Edward (−0.09%) and Rukwa (−3.25%) receded during the period when other lakes were flooding. The information and data presented here provides the most up-to-date quantification of flooding to support adaptation strategies for inland lake systems and guide policy implementation.

Understanding the potential of small water bodies (SWBs) will open greater opportunities in investment towards increased food and energy production. This study established the carrying capacity for fisheries development in SWBs in eight counties in Central and seven counties in Western Kenya. The carrying capacity of SWBs was calculated using socio-economic index (SI), trophic status index (TSI), and summaries of socio-economic and limnological data from 74 SWBs. The central region had a potential of 72,447 t in 37 sampled SWBs, whereas that of the western region had only 447 t in a similar number of sampled sites that forms part of the total national aquaculture potential. The higher potential in the central region is attributed to the relatively larger hydroelectric dams located in the area. To boost production in SWBs with low carrying capacities, restocking with native endemic fish species, which require limited or no supplementary feeding, is recommended. However, in SWBs, where depths reach 3.0 m or more, which optimises on intensive feeding and good water circulation, cage culture reared fish coupled with a strong local community association would be recommended. The indexing holistic approach herein forms an integrative management tool for fisheries production.

We present a GIS-based approach to the delineation of areas that have different levels of suitability for use as tilapia cage culture sites the Kenyan part of Lake Victoria, Africa. The study area was 4,100 km2. The method uses high-resolution bathymetric data, newly collected water quality data from all major fishing grounds and cage culture sites, and existing spatial information from previous studies. The parameters considered are water depth, water temperature, levels of dissolved oxygen, chlorophyll-a concentrations, distances to the lake shoreline and proximity to other constraints on cage culture development. The results indicated that the area most suitable for fish cages comprised about 362 km2, or approximately 9% of the total area; the remaining 91% (i.e., 3,737 km2) was found to be unsuitable for tilapia cage culture. We conclude that the successful implementation of this approach would need stakeholder involvement in the validation and approval of potential sites, and in the incorporation of lake zoning into spatial planning policy and the regulations that support sustainable use while minimising resource use conflicts. The results of this study have broader applicability to the whole of Lake Victoria, other African Great Lakes, and any lakes in the world where tilapia cage culture already occurs or may occur in the future.

Fisheries resources in vital freshwater ecosystems have been reported to be under immense threat, resulting in conflicts between conservation, management and exploitation. This study established requirements for identifying and mapping fish breeding and nursery grounds in such ecosystems in the Kenyan part of Lake Victoria. The criteria were characterised by the use of indigenous knowledge, field data, literature on breeding sites, macroinvertebrates distribution, larval and relative fish abundances, digitisation, participatory mapping, and periodic sampling. Data were collected from trawl and seine net surveys. Digitisation and mapping of the proposed conservation sites were carried out using Quantum GIS software. Participatory physical demarcation of sites was done using buoys and markers. Larval and juvenile fishes were diverse and abundant in all seven river mouths and six bays surveyed with little variance; an important aspect of breeding areas. Additionally, a preponderance of macroinvertebrates and high fish diversity compared with offshore sites in the lake strengthened the hypothesis that these are critical habitats for spawning and preferred habitats for nurseries for fish. The approach can be adopted globally to guarantee the long‐term integrity of critical fish habitats for sustainable fisheries management and blue growth.