The Effect of Simulated African Wild Dog Presence on Anti-predator Behaviour of Kudu and Impala
Résumé
In this study, we examined the behavioural, temporal and spatial effects of simulated African wild dog (Lycaon pictus) presence on its two main prey species: kudu (Tragelaphus strepsiceros) and impala (Aepyceros melampus). We spread African wild dog faeces around waterholes and played African wild dog sounds at different intervals to mimic immediate and non-immediate predation pressure. We looked at anti-predator behaviour at both a herd and individual level and distinguished between high-quality (detracts from all other activities), high-cost vigilance and low-quality (used to monitor the surrounding in spare time), low-cost vigilance to determine costs involved. We found that simulated African wild dog presence had little effect on anti-predator behaviour of their free-ranging prey. Only when immediate predation risk was mimicked did kudu invest in (additional) high-quality vigilance, whereas impala showed no response. Regardless of direct cues of African wild dog presence, behavioural adjustments to reduce predation risk were primarily based on environmental factors such as time of the day and broad-scale habitat structure. Predators have been shown to utilize waterholes to hunt, and prey species are therefore likely to maximize anti-predator behaviour in this high-risk environment based on environmental variables affecting predation risk, the main predator within the system, and water requirements, leaving little flexibility to respond to (simulated) African wild dog presence.