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Predation is an important selective force on prey species, but avoiding predators can be costly. Efficient decisions on who to avoid (predator recognition) and when (situations with different predation risk) will determine the chances of prey survival. In coevolved predator-prey systems, detection of predator odours generally induces a response in potential prey to reduce predation risk. However, prey may not necessarily respond to odours of predators with which they have no previous experience, as predicted by the prey naïveté hypothesis. In turn, perceived predation risk may also modulate predator recognition and the intensity of antipredator responses. In this study, we investigate the responses of an introduced prey species, the European rabbit ( Oryctolagus cuniculus), to odours from coevolved and non-coevolved, sympatric and allopatric predators in situations of high and low numbers of predators in Australia. We used pellet counts to quantify rabbits' use of space on experimental plots treated with predator odours. Rabbit avoidance of plots scented with coevolved predator odours was strongest, but they also responded to non-coevolved, marsupial predators. Predator abundance did not affect predator recognition in rabbits, although responses were more intense in situations where perceived predation risk was low and the intensity of responses decreased over time. Our results suggest that rabbits may have learned to recognize novel marsupial predators after 150 years of exposure in their introduced range. [ABSTRACT FROM AUTHOR]

Early detection of predators by their prey is an essential element of antipredator tactics, and for many mammalian predator prey interactions, detection comes mainly via a predators olfactory cues. The avoidance of predator odors can reduce the likelihood of encountering predators and increases the chances of prey survival. However, the role of coevolutionary history in the exploitation of odors in mammalian predator–prey interactions is not so well understood. The prey naiveté hypothesis predicts the lack of effective antipredator behaviors given the lack of a coevolution between predator and prey but has so far been only tested on native prey. In this study, we describe the short-time responsiveness of an introduced prey species, the European rabbit (Oryctolagus cuniculus), to scents from coevolved and novel predators in Australia. We quantified rabbit activity rates by means of pellet counting and activity indices based on footprints, in a series of experimental plots treated with predator odors, and both methods yielded consistent results. Rabbits responded to coevolved predators by reducing their activity rates to scented experimental plots, whereas no avoidance was found for novel allopatric predators. These results suggest a shared evolutionary history between the antipredatory responses of rabbits and their natural predators. [ABSTRACT FROM PUBLISHER]