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Because avoiding predation is crucial for fitness, foraging animals must trade acquisition of high-quality resources against risk avoidance when the best resources occur in locations with high predation risk. Although optimality models predict the distance at which an animal should initiate vigilance and flight, many studies have shown that animals generally flee soon after detecting an approaching threat, supporting the ‘flush early and avoid the risk’ (FEAR) hypothesis. Despite this, flight behaviour varies markedly depending on context, suggesting some behavioural plasticity in the response of prey to a given threat. We evaluated the degree of plasticity in the flight responses of roe deer, Capreolus capreolus , a highly flexible species which thrives in human-dominated landscapes. Based on individually identifiable animals and a standardized flight initiation protocol, we measured the distance at which a deer detected an approaching threat, and the distance at which it subsequently initiated flight. Our results provide strong support for the FEAR hypothesis, suggesting that alert and flight responses are strongly coupled in roe deer. However, the perceived level of both risk (in terms of landscape openness and proximity to human infrastructure) and reward (in terms of habitat quality) influenced the time it took for a deer to detect an approaching threat, and the subsequent time for which the threat was tolerated prior to flight. Overall, our findings indicate that although roe deer minimize monitoring costs when assessing risk by fleeing early, they also adjust their monitoring and flight responses to the local risk–resource trade-off. [ABSTRACT FROM AUTHOR]

Non-consumptive effects of predators result from the cost of responses to perceived risk. Prey modulate risk exposure through flexible habitat selection at multiple scales which, in interaction with landscape constraints, determines their use of risky habitats. Identifying the relative contributions of landscape constraints and habitat selection to risk exposure is a critical first step towards a mechanistic understanding of non-consumptive effects. Here, we provide an integrative multi-scale study of roe deer spatial responses to variable hunting pressure along a landscape gradient of open habitats and dispersed refuges. Between low-risk and high-risk periods, we investigated shifts in 1) home-range location, 2) probability of using risky habitats (between-habitat scale) and 3) distance to the nearest refuge (within-habitat scale). For 2) and 3), we disentangled the contributions of landscape constraints and habitat selection to risky habitat use. We found that when risk was high, roe deer did not shift their home-range, but generally decreased their use of risky habitats, and sometimes reduced their distance to cover (particularly older animals). There was a functional response in between-habitat selection, with animals living in more open landscapes responding more than those living in landscapes with more refuges. However, individuals living in more open landscapes avoided open risky habitat less. Finally, we found that among-individual variation in risk exposure was generally, but not always, minimized by habitat selection across gradients of landscape constraints. To our knowledge, this is the first study simultaneously documenting prey responses to risk at the within-habitat, between-habitat and home-range scales. Our results support the view that between-habitat selection acts at a higher hierarchical level than within-habitat selection, and provide a framework for disentangling the contributions of habitat selection and landscape constraints to risk exposure. Selection cannot always compensate for landscape constraints, indicating a need for further investigation of the processes underlying habitat selection. [ABSTRACT FROM AUTHOR]

The way an individual reacts to the risk of predation or disturbance may have important consequences for its immediate and future survival. Risk is likely perceived differently by individuals in relation to among-individual differences in correlated behavioral traits, that is, syndromes or personalities. Given that animals can avoid the risk of predation/disturbance through modification of their habitat use, we might expect individuals of differing behavioral types to adopt contrasting tactics of habitat use when faced with risky or stressful situations. We studied the relationship between habitat use and among-individual variation in behavioral profile in a population of roe deer. We hypothesized that an individual's habitat use tactics should be related to their capacity to cope with risky situations. In particular, we predicted that more reactive (risk-averse) roe deer, with relatively high behavioral response and high body temperature at capture, long flight distances and which were more vigilant during feeding, should use riskier open habitat less, particularly when risk is high. We found that although the use of open habitat during the day was negatively correlated with the indices of reactivity at capture, it was also positively correlated with indices of reactivity while foraging in open habitat. Furthermore, most of the behavioral parameters we measured were intercorrelated and moderately repeatable, potentially indexing personality traits. We conclude that there is substantial interindividual variability in how individuals manage risky situations which imposes constraints on how they are able to exploit high-risk habitats, suggesting the existence of a risk management syndrome in this large herbivore. [ABSTRACT FROM AUTHOR]