The utility of Global Positioning System collars in inventorying the diet of lions and its shifts following an anthrax outbreak

Lions (Panthera leo) are a keystone species of many wildlife areas and, as such, understanding their dietary ecology is important for holistic wildlife management. Knowledge of lion feeding ecology enables researchers and wildlife managers to better understand predator–prey dynamics and ecological limits governing their local contexts. Where kill sites can be physically located in the field, they can provide important baseline information on lion diet. In this study, Global Positioning System (GPS) collar data were used together with field observations to investigate the dietary breadth of lions at Malilangwe Wildlife Reserve, Zimbabwe. Results showed that lions in our study had a moderately specialised diet with zebra (Equus quagga) constituting the largest proportion of prey species consumed. A massive anthrax outbreak occurred during the study, drastically reducing numbers of several prey species, and this provided an opportunity to test possible shifts in lion diet in response to changes in prey abundance. Prey species selection before the anthrax outbreak was significantly different to the period after the outbreak, indicating a shift in diet post-outbreak. Notable increases were observed in kill rates of species that were not severely affected by anthrax, namely warthog (Phacochoerus africanus), zebra, wildebeest (Connochaetes taurinus) and eland (Taurotragus oryx). Quantifying lion dietary requirements is important for assessing the ecological and economic impacts they have on prey populations. In addition to space-use ecology, this study shows that GPS collar data can facilitate diet investigation in large carnivores thereby providing useful information for ecological management.