Lake Nakuru Research Articles

Modeling Black Rhinoceros (Diceros bicornis) Population Performance in East Africa: The Case of Lake Nakuru National Park, Kenya

The black rhinoceros have declined across Africa both in numbers and range distribution, making long-term population persistence of this iconic species uncertain. We conducted simulation models to predict population performance of black rhinoceros in Lake Nakuru National Park under different scenarios of environmental variation and translocation regimes. A decade-long (1987-1997) demographic data were used to construct stochastic simulation models using VORTEX computer program. In addition, we assessed extinction risks and patterns of heterozygosity among the modelled populations (reported every five years) to characterize the dynamics of this population over a hundred years. The population of black rhinoceros showed varying patterns of fluctuations under different scenarios. The best-case scenario showed a considerable increase in the modelled population with the population attaining the highest growth (population growth (λ)=1.04) after 40 years. The mean final population size for the successful cases was 70.85 ± 2.0 animals, which was relatively close to the carrying capacity used in the simulation. The expected heterozygosity was 0.912 ± 0.02 suggesting that the remaining population may be genetically viable. Further, environmental variation of 1-2% magnitude across the various age categories, and without translocation, had no significant effect on the deterministic growth rate of the population. Maintaining the translocation of 2 males and 2 females on yearly basis would significantly boost and sustain the population of black rhinoceros in the study area.

Late-Holocene and recent hydroclimatic variability in the central Kenya Rift Valley: The sediment record of hypersaline lakes Bogoria, Nakuru and Elementeita

The sedimentology, salt mineralogy and stable oxygen- and carbon-isotope signatures of a mid-lake sediment sequence from hypersaline Lake Bogoria in Kenya reveal marked climate-driven changes in water-column mixing regime and salinity over the past 1700years. Combined with sedimentological data on short sediment sequences from nearby lakes Nakuru and Elementeita, this results in a preliminary reconstruction of hydroclimatic variability in the central Kenya Rift Valley since ca. 300 AD. Stratigraphic analyses of bulk sediment composition, texture and magnetic susceptibility of all three cores; and smear slide, XRD and stable-isotope analyses on carbonate minerals in the Bogoria sequence allowed to define a succession of sedimentary units, corresponding to distinct phases in lake history. In the lowermost unit, four characteristic trona layers (Na3(HCO3)(CO3)·2H2O) are attributed to predominantly dry conditions during the second half of the first millennium AD and the period equivalent to the Medieval Climate Anomaly, until the first half of the 12th century AD. Lake Bogoria was probably polymictic at that time, its surface level standing significantly lower than today. The second unit displays uniform deposition of nahcolite (NaHCO3), indicative of a strongly stratified lake where a layer of less saline surface water (near-)permanently covers a hypersaline water mass with high pCO2. We propose that this depositional phase reflects the rising lake level related to the transition from dry to more humid climate conditions at the onset of the Little Ice Age, as previously documented for other parts of equatorial East Africa. The third, uppermost Bogoria unit contains only sporadic depositions of magadiite (Na2Si14O29(OH)3·11H2O) and various sodium carbonate minerals. This, together with low magnetic susceptibility, is interpreted to indicate humid Little Ice Age conditions, with highest lake level and reduced salinity around the late-15th to early-16th century AD. From the late-18th to early-19th century and again in the 1870's, the region experienced two episodes of drought more severe than any recorded in historical time. Tentative evidence for these events in the Bogoria record is not well constrained in time, but dated desiccation surfaces in the Nakuru and Elementeita records confirm their widespread nature across eastern equatorial Africa.

Remotely sensing the spatial and temporal land cover changes in Eastern Mau forest reserve and Lake Nakuru drainage basin, Kenya

This study aimed at characterizing land cover dynamics for four decades in Eastern Mau forest and Lake Nakuru basin, Kenya. The specific objectives were to: (i) identify and map the major land cover types in 1973, 1985, 2000 and 2011; (ii) detect and determine the magnitude, rates and nature of the land cover changes that had occurred between these dates, and; (iii) establish the spatial and temporal distribution of these changes. Land cover types were discriminated through partitioning, hybrid classification and spatial reclassification of multi-temporal Landsat imagery. The land cover products were then validated and overlaid in post-classification comparison to detect the changes between 1973 and 2011. The accuracies of the land cover maps for 1973, 1985, 2000 and 2011 were 88%, 95%, 80% and 89% respectively. Six land cover classes, namely forests-shrublands, grasslands, croplands, built-up lands, bare lands and water bodies, were mapped. Forests-shrublands dominated in 1973, 1985 and 2000 covering about 1067 km2, 893 km2 and 797 km2 respectively, but were surpassed by croplands (953 km2) in 2011. Bare lands occupied the least area that varied between 2 km2 and 7 km2 during this period. Overall, forests-shrublands and grasslands decreased by 428 km2 and 258 km2 at the annual average rates of 1% each, whereas croplands and built-up lands expanded by 660 km2 and 24 km2 at the annual rates of 6% and 16% respectively. The key hotspots of these changes were distributed in all directions of the study area, but at different times. Therefore, policies that integrate restoration and conservation of natural ecosystems with enhancement of agricultural productivity are strongly recommended. This will ensure environmental sustainability and socio-economic well-being in the area. Future research needs to assess the impacts of the land cover changes on ecosystem services and to project the future patterns of land cover changes.

Using the Soil and Water Assessment Tool (SWAT) to assess land use impact on water resources in an East African watershed

Summary Land cover and land use changes in Kenya’s Rift Valley have altered the hydrologic response of the River Njoro watershed by changing the partitioning of excess rainfall into surface discharge and groundwater recharge. The watershed contributes a significant amount of water to Lake Nakuru National Park, an internationally recognized Ramsar site, as well as groundwater supplies for local communities and the city of Nakuru. Three land use maps representing a 17-year period when the region underwent significant transitions served as inputs for hydrologic modeling using the Automated Geospatial Watershed Assessment (AGWA) tool, a GIS-based hydrologic modeling system. AGWA was used to parameterize the Soil and Water Assessment Tool (SWAT), a hydrologic model suitable for assessing the relative impact of land cover change on hydrologic response. The SWAT model was calibrated using observation data taken during the 1990s with high annual concordance. Simulation results showed that land use changes have resulted in corresponding increases in surface runoff and decreases in groundwater recharge. Hydrologic changes were highly variable both spatially and temporally, and the uppermost reaches of the forested highlands were most significantly affected. These changes have negative implications for the ecological health of the river system as well as Lake Nakuru and local communities.

Nonlinear Correlation analysis between Surface Resistivity and Hydraulic Characteristics of the Kabatini Well Field, Upper Lake Nakuru Basin, Kenya Rift

The purpose of the study was to find and examine correlation relationships between field-scale hydraulic parameters and pore-scale geo-electrical parameter controlling groundwater occurrence in Kabatini aquifer of Upper Lake Nakuru Basin, Kenya. The study has taken under consideration priori published resistivity sounding and hydrological parameters and depth of water table from drill siteswhich is used to constrain ambiguity of interpretation. An attempt has been made to derive general functional relationships between hydraulic parameters and geo-electric property of the aquifer.The observed hydraulic data from pumping test is correlated non- linearly with aquifer electrical resistivity. The formation resistivity factor was found vary partially with pore volume and pore surface distribution. Porosity as a function of aquifer resistivity was best defined by a negative power law function, whereas transmissivity dependence on resistivity was found to bear a positive power law. The aquifer parameters information thus obtained from resistivitysounding and pumpingtest data can be used for optimal management and assessment of groundwater resources.

Amino acid neurotoxins in feathers of the Lesser Flamingo, Phoeniconaias minor

The Lesser Flamingo (Phoeniconaias minor) is known to use cyanobacteria (primarily Arthrospira) as a major food source in the East African Rift Valley lakes. Periodically, mass mortalities have occurred, associated with the cyanobacterial toxins (cyanotoxins), microcystins and anatoxin-a. Deposition of these cyanotoxins into P. minor feathers has been shown to occur, consistent with the presence of cyanotoxins in the livers, stomach and faecal contents after dietary intake. As cyanobacteria have been shown to also produce the neurotoxins β-N-methylamino-l-alanine (BMAA) and 2,4-diaminobutyric acid (DAB), stored wing feathers, previously recovered from flamingos which had been exposed to microcystins and anatoxin-a and had subsequently died, were analysed for these neurotoxic amino acids. Trace amounts of BMAA were detected in extracts from Lake Nakuru flamingo feathers, with DAB also present at concentrations between 3.5 and 8.5μgg−1 dry weight in feathers from both lakes. Toxin recovery by solid-phase extraction of feather digests was tested with spiked deuterated BMAA and showed good recovery when analysed by LC–MS/MS (80–94%). This is the first report of these neurotoxic amino acids in birds. We discuss the origin and significance of DAB, alongside other cyanotoxins of dietary origin, in the feathers of the Lesser Flamingo.

Major and trace element geochemistry of Lake Bogoria and Lake Nakuru, Kenya, during extreme draught

The physico-chemical properties of water samples from the two athalassic endorheic lakes Bogoria and Nakuru in Kenya were analysed. Surface water samples were taken between July 2008 and October 2009 in weekly intervals from each lake. The following parameters were determined: pH, salinity, electric conductivity, dissolved organic carbon (DOC), the major cations (FAAS and ICP-OES) and the major anions (IC), as well as certain trace elements (ICP-OES). Samples of superficial sediments were taken in October 2009 and examined using Instrumental Neutron Activation Analysis (INAA) for their major and trace element content including rare earth elements (REE). Both lakes are highly alkaline with a dominance of Na>K>Si>Ca in cations and HCO3>CO3>Cl>F>SO4 in anions. Both lakes also exhibited high concentrations of Mo, As and fluoride. Due to an extreme draught from March to October 2009, the water level of Lake Nakuru dropped significantly. This created drastic evapoconcentration, with the total salinity rising from about 20‰ up to 63‰. Most parameters (DOC, Na, K, Ca, F, Mo and As) increased with falling water levels. A clear change in the quality of DOC was observed, followed by an almost complete depletion of dissolved Fe from the water phase. In Lake Bogoria the evapoconcentration effects were less pronounced (total salinity changed from about 40‰ to 48‰). The distributions of REE in the superficial sediments of Lake Nakuru and Lake Bogoria are presented here for the first time. The results show a high abundance of the REE and a very distinct Eu depletion of Eu/Eu*=0.33–0.45.

Hidden diversity of eukaryotic plankton in the soda lake Nakuru, Kenya, during a phase of low salinity revealed by a SSU rRNA gene clone library

A SSU rRNA gene clone library was constructed to establish the diversity of eukaryotic plankton in the African soda lake Nakuru during a phase of low salinity (9.7 ppt = hyposaline). Normally, the lake is mesosaline (up to 50 ppt) and its phytoplankton is dominated by few species of cyanobacteria, in particular Arthrospira fusiformis, which is the main food resource of Lesser Flamingos. Our study recovered a unique phytoplankton species composition characterized by a high diversity of monadoid and coccoid green algae. Out of 77 clones detected, 52 belonged to Chlorophyta. Many of the chlorophytes were transported from the catchment area into the lake through small seasonal rivers and an outflow of the Nakuru town sewage treatment plant. Other phylogenetic groups detected were Fungi, Cryptophyta, Jakobida, Alveolata, Stramenopiles, and Metazoa. Our findings reveal a hidden diversity, which would not have been detected by traditional observations.

A detailed time series assessment of the diet of Lesser Flamingos: further explanation for their itinerant behaviour

We hypothesised that changes in nutritional composition and quality of the pelagic phytoplankton community influence the occurrence of Lesser Flamingo populations in two Kenyan saline–alkaline lakes, Nakuru and Bogoria. This was achieved by carrying out a detailed time series assessment of the phytoplankton community composition and nutritional components (carbohydrates, crude protein and lipids) from July 2008 to October 2009 on a weekly basis for each lake. Lesser Flamingos were estimated visually from the lake shore of the sampling sites. In Lake Nakuru, Lesser Flamingos had a significant positive relationship with lipids and Arthrospira biomass but a negative relationship with small cyanoprokaryotes. For Lake Bogoria, no significant differences were observed as the Arthrospira was available throughout the sampling period though the flamingo numbers still fluctuated. We concluded that the nutritional composition and quality of the phytoplankton community influence the temporal and spatial abundance of Lesser Flamingos although other factors such as the prevailing environmental conditions may take precedence.

Haloleptolyngbya alcalis gen. et sp. nov., a new filamentous cyanobacterium from the soda lake Nakuru, Kenya

The food web of the saline-alkaline Lake Nakuru is dominated by the cyanobacterium Arthrospira fusiformis as the primary producer and a huge population of Lesser Flamingos as direct consumers. However, the dense blooms of Arthrospira are not stable, and collapse irregularly and unpredictably. During such periods they are replaced by other algae or cyanobacteria. The wide fluctuation in the cyanobacterial and algal populations of Lake Nakuru has a great influence on food availability for Lesser Flamingos, and is therefore of high ecological importance. To support the descriptive work on these phenomena, we describe here a new cyanobacterial taxon from this soda lake: Haloleptolyngbya alcalis Dadheech, Mahmoud, Kotut et Krienitz gen. et sp. nov. The study was based on multilocus molecular analyses of 16S rRNA gene, 16S-23S internal transcribed spacer, partial sequences of beta and alpha subunits including intergenic spacer (cpcBA-IGS) of phycocyanin operon, phenotypic features using light microscopy, scanning electron microscopy, transmission electron microscopy, and ecology. The new taxon established a separate lineage within the family of Peudanabaenaceae (Oscillatoriales).

Dynamics of ungulates in relation to climatic and land use changes in an insularized African savanna ecosystem

Land use change and human population growth are accelerating the fragmentation and insularization of wildlife habitats worldwide. The conservation and management of wildlife in the resultant ‘island’ ecosystems in the context of global warming is challenging due to the isolation and reduced size of the ecosystems and hence the scale over which ecosystem processes can operate. We analyzed trends in numbers of nine large herbivores in Kenya’s Lake Nakuru National Park to understand how rainfall and temperature variability, surrounding land use changes, and boundary fencing affected wildlife population dynamics inside the park during 1970–2011. Buffalo, zebra and Thomson’s gazelle numbers increased persistently. Grant’s gazelle and impala increased initially then gradually declined. Waterbuck and warthog numbers progressively declined to levels that potentially threatened their local population persistence. The total biomass of ungulates tripled from 1970 to 2011, with buffalo replacing waterbuck as the predominant species in biomass. Increased competition from buffalo and zebra, heightened predation and illicit human harvests probably all contributed to the declines by waterbuck and warthog. Density-dependent limitation of population growth within the park confines was evident for buffalo, impala, eland, giraffe, Grant’s and Thomson’s gazelles. Fluctuations in the lake level related to varying rainfall affected changes in animal abundance through expansion of the lake area and flooding of grasslands bordering the lake. Unusually, the most stressful conditions were associated with high water levels following high rainfall. There was also evidence of carry-over effects from prior habitat conditions affecting all species. The relatively stable populations of all species except warthog and waterbuck demonstrate the remarkable capacity of this small, insularized park to retain viable populations of most of the large herbivores, without much management intervention.

Picocystis salinarum (Chlorophyta) in saline lakes and hot springs of East Africa

Krienitz L., Bock C., Kotut K. And Luo W. 2012. Picocystis salinarum (Chlorophyta) in saline lakes and hot springs of East Africa. Phycologia 51: 22–32. DOI: 10.2216/11-28.1The occurrence of Picocystis salinarum in saline inland waters of East Africa was investigated using a polyphasic approach of small-subunit (SSU) rDNA phylogeny and light microscope observations. Recent studies have found that Picocystis occasionally replaces the dominant cyanobacterium (Arthrospira fusiformis), which is the main food resource of Lesser Flamingos, in soda lakes of Bogoria and Nakuru. This article discusses the consequences of a high abundance (maximum cell numbers of > 3 billion cells l−1) of Picocystis on food chains of African saline waters. During the study, we found a new morphotype of Picocystis characterized by larger cell sizes and absence of lobes in hot springs near Lake Magadi. SSU rRNA genes of Picocystis strains and uncultured field clones collected from Lake Nakuru were subjected to phylogenetic analyses together with other picoplankton from field and culture samples from saline, marine or freshwater. Picocystis salinarum from saline inland waters represents a link between marine and freshwater habitats from both an ecological and a phylogenetic point of view and is therefore of great interest.

Zooplankton partitioning in a tropical alkaline–saline endorheic Lake Nakuru, Kenya: Spatial and temporal trends in relation to the environment

Spatial and temporal zooplankton variations were studied for 1 year in tropical alkaline–saline Lake Nakuru to determine how they partition in the habitat, relative to environmental variables. Monthly samples were collected at 10 sampling sites, with subsurface tows, using 33.5-μm mesh plankton nets. Physicochemical parameters displayed clear seasonal variations associated with precipitation patterns. Nine species, belonging to two main zooplankton taxonomic groups (ciliates; rotifers), were identified in the samples. Brachionus dimidiatus dominated the samples, accounting for 80% of the total zooplankton abundance. Kruskall–Wallis tests indicated significant (P < 0.05) temporal and spatial variations among all taxonomic groups. Different zooplankton species displayed a clear succession throughout the year. The total abundance of the rotifers and ciliates peaked at sampling sites near inlets during the long rainy seasons, while those in the inshore sites displayed variable succession patterns. Spatiotemporal structure of the zooplankton assemblages, and its correlation with environmental variables, indicated each species displayed distinct niche-based partitioning. The ciliates niche was associated with increasing soluble reactive phosphorus, total phosphorus and nitrite–nitrogen (NO2–N) concentrations. Niche partitioning in rotifers was associated with nitrate–nitrogen (NO3–N), conductivity and pH. These results indicate physical niche separation, even in a small, relatively homogenous lake among species of rotifers and ciliates, providing information from which future changes in their abundance and spatial distributions can be predicted, given continuous water quality changes.

Distribution, density and impact of invasive plants in Lake Nakuru National Park, Kenya

AbstractInvasive plants have invaded swathes of grasslands in Lake Nakuru National Park thus necessitating the Park management to institute measures to control them. Despite this, information on the status and impact of invasive plants in these grasslands is lacking. Six grassland types were identified and assigned random numbers. Five study sites were then randomly selected from each grassland type. The Point‐Centre Quarter method was used to determine the distribution and density of seven major invasive plants, whilst their impact was assessed by comparing biomass and crude protein content of important forage grasses in invaded and noninvaded grasslands. Results show that the distribution of invasive plants did not differ among the grasslands (F5, 30 = 1.47, P = 0.229) but their densities differed among the plants (F6, 30 = 20.99, P &lt; 0.001). The mean biomass in invaded and noninvaded grasslands (22 g m−2 versus 37.2 g m−2) was significantly different (t‐test, P &lt; 0.05), while crude protein content of grasses in invaded (7.73, % DM) and noninvaded (9.3, % DM) patches was not significantly different (t‐test; P &gt; 0.05). Our results suggest that invasive plants lower grass production and hence might reduce food availability to grazers.

Distribution of Cd and Zn Levels in Soils and Acacia xanthophloea Benth. from Lake Nakuru National Park Kenya

Cadmium and zinc from anthropogenic sources in Lake Nakuru were investigated. High metal levels (mg/kg) in soils (Cd < or = 16.3 and Zn < or = 280) and Acacia xanthophloea (Cd < or = 32 and Zn < or = 310) were observed at polluted sites. Significant variations in metal values were evaluated using ANOVA (F test) and student's t test at p < 0.05 and metal correlations studied. High levels of metals in soils and unhealthy/dying Acacia were obtained at polluted sites. Significant positive correlation was obtained between Cd and Zn in soils and plants. Acacia sp are effective biomonitor of environmental quality in areas subjected to pollution.

Implications of closed ecosystem conservation management: the decline of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) in Lake Nakuru National Park, Kenya

AbstractGiraffe were historically free‐ranging across most of sub‐Saharan Africa but are now most often confined to national parks, conservation areas, or private ranches. Five viable populations of Rothschild’s giraffe (Giraffa camelopardalis rothschildi) remain in protected areas in Kenya and Uganda. The viable population in Uganda is Murchison Falls National Park and the four populations in Kenya are Lake Nakuru National Park (LNNP), Ruma National Park, Giraffe Manor, and Mwea Natural Reserve. The Kenya Wildlife Service queried a rapid decline in LNNP giraffe numbers falling from 153 individuals (1995) to 62 individuals (2002) and the failure of that population to recruit young in those years. Significantly reduced browse options, inbreeding depression and preferential lion predation were considered as potential reasons for this trend. Population genetic parameter estimates derived from multilocus genotype analyses suggest that the LNNP population was in good genetic health with respect to the likelihood of inbreeding depression. The population decline coincided with the drought attributed to the 1994 El Niño. Possible dietary complications from highly concentrated tannin levels because of forced over consumption of the park’s declining acacia trees may have compromised young giraffe, making them easy and opportunistic prey for the park’s lion population.

Tectonic and climatic control on evolution of rift lakes in the Central Kenya Rift, East Africa

The long-term histories of the neighboring Nakuru–Elmenteita and Naivasha lake basins in the Central Kenya Rift illustrate the relative importance of tectonic versus climatic effects on rift-lake evolution and the formation of disparate sedimentary environments. Although modern climate conditions in the Central Kenya Rift are very similar for these basins, hydrology and hydrochemistry of present-day lakes Nakuru, Elmenteita and Naivasha contrast dramatically due to tectonically controlled differences in basin geometries, catchment size, and fluvial processes. In this study, we use eighteen 14C and 40Ar/ 39Ar dated fluvio-lacustrine sedimentary sections to unravel the spatiotemporal evolution of the lake basins in response to tectonic and climatic influences. We reconstruct paleoclimatic and ecological trends recorded in these basins based on fossil diatom assemblages and geologic field mapping. Our study shows a tendency towards increasing alkalinity and shrinkage of water bodies in both lake basins during the last million years. Ongoing volcano-tectonic segmentation of the lake basins, as well as reorganization of upstream drainage networks have led to contrasting hydrologic regimes with adjacent alkaline and freshwater conditions. During extreme wet periods in the past, such as during the early Holocene climate optimum, lake levels were high and all basins evolved toward freshwater systems. During drier periods some of these lakes revert back to alkaline conditions, while others maintain freshwater characteristics. Our results have important implications for the use and interpretation of lake sediment as climate archives in tectonically active regions and emphasize the need to deconvolve lacustrine records with respect to tectonics versus climatic forcing mechanisms.

Browsing impact of large herbivores on Acacia xanthophloea Benth in Lake Nakuru National Park, Kenya

AbstractSignificant differences (P&lt;0.05) were found in growth of plant height, canopy cover and stem diameter of Acacia xanthophloea trees in fenced plot as compared with unfenced plot both in the wet and in the dry seasons. Finding of this study showed that although heavy browsing reduced the height and canopy of trees, it did not kill any trees and seedling regeneration took place simultaneously. Despite the presence of large herbivores that impact some considerable browsing pressure results indicate that the A. xanthophloea habitat type would continue to remain in balance in the presence of recruitment of seedlings and saplings. The conditions at the time of study indicate that the browsing on A. xanthophloea was not significant and was not serious enough to warrant management intervention at present.

Spatial and seasonal variations in phytoplankton community structure in alkaline–saline Lake Nakuru, Kenya

AbstractSpatial and seasonal variations of phytoplankton, expressed in terms of species composition, cell density, biovolumes and biomass, collected at 10 sampling sites in alkaline–saline Lake Nakuru, Kenya, were investigated monthly from March 2004 to February 2005, in relation to selected physical and chemical water quality parameters. A total of eight species, belonging to five genera and three classes, were recorded. The Cyanophyceae comprised the bulk of the phytoplankton, followed by Euglenophyceae, while Bacillariophyceae were the least abundant. Arthrospira fusiformis was the most dominant species, in terms of density, among the Cyanophyceae, while Euglena spp. and Navicula elkabs dominated the Euglenophyceae and Bacillariophyceae density, respectively. Seasonal variations in phytoplankton species composition, density and biomass were significant (P &lt; 0.05) with minimum cell density and biomass occurring during the dry season, and being maximum following the end of the two rainy seasons from May to November 2004, suggesting the possible influence of various environmental factors on the lake. Sampling sites located close to the inlets of inflowing rivers exhibited significantly (P &lt; 0.05) higher phytoplankton cell density and biomass than those by the inshore sites. Soluble reactive phosphorus, ammonia‐nitrogen, conductivity and total alkalinity accounted for most of the variations in the cell densities of phytoplankton species.

Impact of land use changes on water resources and biodiversity of Lake Nakuru catchment basin, Kenya

AbstractLake Nakuru, Kenya, is one of a series of saline–alkaline closed basin lakes in the eastern arm of the Rift Valley. The lake has been variously described as ‘the lake of a million flamingos’ and ‘the Worlds greatest ornithological spectacle’ and is bedrock to the areas’ tourism. The lake was designated a bird sanctuary in 1960, a National Park in 1968, first rhino sanctuary in 1987, first Kenyan Ramsar site in 1990, an Important Bird Area in 1999 and a world‐class national park in 2005. Over the last 40 years, its basin has been heavily settled, extensively cultivated, urbanized and industrialized. Environmental problems include poor agricultural practices, human encroachment, pollution, wildlife mortality/morbidity, human/wildlife conflicts, poverty, ethnic tensions and land clashes and lack of adequate legal and policy framework. Approaches to conservation have been initiated against identified existing problems and constraints. These approaches are (i) organizational and institutional development; (ii) hot spots and pollution loads management and (iii) catchment and park management. Constraints have been identified as unclear demarcation of responsibilities, lack of budget, skilled staff and know‐how and lack of environmental standards and regulations. The impacts of ecosystem changes on people’s lives and livelihoods are discussed.