Little to fear: largest lizard predator induces weak defense responses in ungulate prey

Non-consumptive effects can strongly influence apex predator ecological function. These effects arise because prey produce often induce costly phenotypic responses to mitigate predation risk. Yet because predator-prey interactions are complex, prey defences may vary considerably. We investigated if the Komodo dragon (Varanus komodoensis), an reptile apex predator, induced multi-scale anti-predator responses in key prey, the Rusa deer (Cervus timorensis) and the wild pig (Sus scrofa). To this end, we examined the temporal and spatial partitioning of habitats by predator and prey, determined the size of ungulate groups as a function of risk, and assessed changes in individual behavior of prey individuals exposed to predator kairomones at feeding stations. Komodo dragon, deer and pig populations exhibited significant, but subtle differences in three habitat preferences, that otherwise indicated high niche overlap. Komodo dragon predation risk, alongside other commonly considered predictor ...