Lion (Panthera leo) diet and cattle depredation on the Kuku group ranch pastoralist area in Southern Maasailand, Kenya

Abstract

African lion (Panthera leo) populations are declining throughout Africa, but the problem is particularly acute in southern Kenya, where human–lion conflict is common. Aims. Using the Kuku Group Ranch (KGR) in southern Kenya as a case study, we investigated lion diet and the potential drivers of temporal variation in cattle depredation. Methods. Using GPS clusters, we investigated the main prey species consumed by lions to determine lion diet. Prey preference of lions in relation to prey availability was then assessed using a Jacobs index to determine whether cattle or wild prey were preferred. We used reported depredation events recorded by verification officers over 36 months (2016–2018) to investigate whether temporal variation in cattle depredation by lions was linked to variation in lag rainfall, normalised difference vegetation index (NDVI) or availability of the most important large non-domestic prey items. Key results. Six prey species (cattle, Bos taurus; Burchell’s zebra, Equus quagga; Coke’s hartebeest, Alcelaphus cokeii; Maasai giraffe, Giraffa tippelskirchi; blue wildebeest, Connochaetes taurinus; and eland, Tragelaphus oryx) made up 92% of the biomass consumed by lions on KGR. Cattle are the most consumed prey item and contribute the second most to consumed biomass after giraffe. However, once prey availability is considered, lions preferred wild prey. Verification officers identified 330 cattle depredation events over 3 years, and we show that the most important predictor of monthly cattle depredation by lions was cumulative rainfall in the preceding 3 months. Conclusions. Our results on cattle depredation by lions showed that rainfall and its influence on the environment are important drivers of cattle depredation. Understanding the mechanistic link between lion depredation and rainfall enables us to predict when depredation events may increase and allows hypotheses on the reason why this spike in depredation takes place to be explored. Implications. Given that climate-change models indicate that East Africa will experience prolonged and increased seasonal rainfall, we predict that periods when cattle are vulnerable to lion depredation may increase. Therefore, it is imperative to ensure that cattle husbandry is improved during these wetter periods to minimise the risk of conflict and retaliatory killing of lions.