Migratory herds of wildebeests and zebras indirectly affect calf survival of giraffes
In long-distance migratory systems, local fluctuations in the predator–prey ratio can exhibit extreme variability within a single year depending upon the seasonal location of migratory species. Such systems offer an opportunity to empirically investigate cyclic population density effects on short-term food web interactions by taking advantage of the large seasonal shifts in migratory prey biomass. […]
Does the risk of encountering lions influence African herbivore behaviour at waterholes?
A central question in the study of predator–prey relationships is to what extent prey behaviour is determined by avoidance of predators. Here, we test whether the long-term risk of encountering lions and the presence of lions in the vicinity influence the behaviour of large African herbivores at waterholes through avoidance of high-risk areas, increases in […]
Large predators and their prey in a southern African savanna: a predator’s size determines its prey size range
A long‐term (13‐year) data set, based on > 4000 kills, was used to test whether a sympatric group of large predators adheres to the theoretical predictions that (1) mean prey body size and (2) prey diversity increase as functions of predator body size. All kills observed by safari guides are documented routinely in Mala Mala Private Game […]
Oscillations in large mammal populations: are they related to predation or rainfall?
Cyclic population dynamics is relatively common among populations of small mammals in high latitudes but is not yet established among African savanna ungulates. However, oscillations may be expected in large mammal populations subject to quasi-periodic oscillations in regional rainfall. We evaluated evidence for environmentally entrained oscillations in a large-mammal predator–prey system in Kruger National Park […]