ORIGINAL PAPER Behavioural responses to indirect and direct predator cues by a mammalian herbivore, the common brushtail possum Carolyn L. Nersesian & Peter B. Banks & Clare McArthur Received: 7 May 2011 /Revised: 18 August 2011 /Accepted: 19 August 2011 /Published online: 7 September 2011 # Springer-Verlag 2011 Abstract Cues for detecting and responding to perceived predation risk may be indirect, i.e., correlated with the probability of encountering a predator, or direct, i.e., produced by or related to the actual presence of a predator. Research shows, independently, both types of cues can influence anti-predator and foraging behaviours in prey species. However, since animals naturally encounter indirect and direct cues simultaneously, we were interested in quantifying their cumulative effect. Our aim was to evaluate food intake and behaviours (patch use, feeding (rate and time), vigilance) of a nocturnal mammalian herbivore to indirect (open vs. covered microhabitats; illumination) and direct (fox/ owl odours) predator cues. We ran a preference trial with four paired treatments using a covered Safe food patch and an open Risk food patch, with one of four combinations of indirect and direct predator cues. Predation risk had a significant effect on both intake and behaviour (including feeding time, rate, and vigilance), but these effects differed depending on cues. No two combinations of cues produced exactly the same effects, illustrating the complexity of interactions that occur between cues. Covered patches were always perceived as less risky than open patches, but unexpectedly, open patches were perceived as riskier when dark rather than light. The strongest suite of (negative) responses to risk was associated with combined indirect and direct cues. These results highlight the importance of considering jointly, intake from a patch, intake rate, and behaviours, such as the proportion of time spent vigilant, when quantifying predation risk, rather than intake alone. Keywords Foraging . Herbivore . Interactions . Patch use . Predation risk . Predator cues Introduction Searching for food exposes a forager to increased risk of predation. Therefore, decisions regarding when and where an individual should forage often involve balancing food and safety, and the tactics prey use in response to these conflicting demands can be costly (Brown et al. 1999; Brown and Kotler 2004). For example, individuals may sacrifice foraging efficiency, for safety, by allocating time among safe and risky habitats, and/or by using vigilance while at a patch, ultimately resulting in reduced energy gain (Sih 1980; Brown 1999). Even so, behavioural responses, such as choosing where and how long to spend at a food patch, or employing a particular level of vigilance, can significantly reduce actual mortality (Lima and Dill 1990; Brown 1999; Preisser et al. 2005). Managing the trade-off Communicated by P. Bednekoff Electronic supplementary material The online version of this article (doi:10.1007/s00265-011-1250-y) contains supplementary material, which is available to authorized users. C. L. Nersesian : P. B. Banks : C. McArthur School of Biological Sciences, University of Sydney, New South Wales 2006, Australia P. B. Banks e-mail: p.banks@sydney.edu.au C. McArthur e-mail: clare.mcarthur@sydney.edu.au C. L. Nersesian (*) Départment de biologie, Pavillon Alexandre-Vachon, 1045, av. de la Médecine, Québec, QC G1V 0A6, Canada e-mail: carolyn.nersesian@bio.ulaval.ca C. L. Nersesian e-mail: carolyn.nersesian@sydney.edu.au Behav Ecol Sociobiol (2012) 66:47–55 DOI 10.1007/s00265-011-1250-y