Fig 1.
a) A map showing the properties constituting the Nakuru Wildlife Conservancy and the neighbouring non-conservancy properties in the Naivasha-Nakuru region of Kenya (Left panel). b) A map showing the areas covered by the total counts in the Nakuru Wildlife Conservancy and the neighbouring non-conservancy properties in the Naivasha-Nakuru region of Kenya (right panel). Areas covered by the total counts are labeled with alphabetical letters.
Fig 2.
a) The distribution of the total monthly rainfall across months in Nakuru Wildlife conservancy averaged over 1967 and 2011 and the standardized deviates for the b) annual, c) wet season and d) dry season rainfall components.
The vertical needles in panels b-d are the observed standardized deviates, the thick solid lines are the 4-year moving averages for the annual and wet season rainfall components and the 3-year moving average for the dry season rainfall component. The dashed horizontal lines are the percentiles of the standardized deviates for each rainfall component. The two dashed curves in the panel for the wet season rainfall are the secondary cycles with 3.5 and 2.2-year periods.
Table 1.
The estimated variances of the disturbance terms, the variances of the irregular component, damping factor and period of the cycles in annual, wet and dry season rainfall components.
Table 2.
Significance analysis of components (based on the final state).
Fig 3.
Trends in the density (Number /km2) of steinbuck, bushbuck, hartebeest, Greater kudu, klipspringer, mongoose, oribi, porcupine, cheetah, leopard, ostrich and Sykes monkey for the entire Nakuru Wildlife Conservancy during 1996–2015.
Fig 4.
Trends in the density (Number /km2) of dik dik, eland, African hare, jackal, duiker, hippopotamus, Thomson’s gazelle, aardvark, serval cat, colobus monkey, bat-eared fox and reedbuck for the entire Nakuru Wildlife Conservancy during 1996–2015.
Fig 5.
Trends in the density (Number /km2) of hyena, baboon, Grant’s gazelle, Grevy’s zebra, lion, spring hare, Burchell’s zebra, bushpig, white rhino, rock hyrax, topi and oryx for the entire Nakuru Wildlife Conservancy during 1996–2015.
Fig 6.
Trends in the density (Number /km2) of vervet monkey, guinea fowl, giraffe, wildebeest, impala, buffalo, warthog and waterbuck for the entire Nakuru Wildlife Conservancy during 1996–2015.
Fig 7.
Temporal trends in the aggregate biomass of the 32 herbivore species, 4 primate species and 8 carnivore species counted in the Nakuru Wildlife Conservancy from 1996 to 2015.
The species and their unit weights [39] are listed in S2 Table in the supplementary materials. The vertical needles are the biomass estimates, the thick solid line is the trend line and the band around the line is the 95% confidence band fitted by penalized cubic basis spline regression.
Fig 8.
The relationship between the a) aggregate herbivore biomass versus 8-year moving average of the early wet season (March-May) rainfall, r = 0.89593, 95% CI: 0.705286–0.961465, P = 1.6734 × 10−7, n = 16 years) and b) aggregate herbivore biomass versus 8-year moving average of the wet season (March-August) rainfall, r = 0.79912, 95% CI: 0.482269–0.923621, P = 7.7404 × 10−5, n = 16 years).
The 32 herbivore species and the unit weights (in kg) used to calculate aggregate biomass are listed under herbivores in S2 Table in the supplementary materials.