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Predators can indirectly affect prey survival and reproduction by evoking costly antipredator responses. Such nonconsumptive effects may be as strong or stronger than consumptive predator effects. However, evidence for this in large terrestrial vertebrate systems is equivocal and few studies quantify the actual fitness costs of nonconsumptive effects. Here, we investigated whether nonconsumptive effects elicited by Eurasian lynx (Lynx lynx), a large terrestrial predator, reduced survival in an ungulate prey, the European roe deer (Capreolus capreolus). To reveal the behavioral processes underlying nonconsumptive effects, we distinguished between proactive risk avoidance of areas with high lynx encounter probability, and reactive risk avoidance in response to actual lynx encounters and analyzed these responses using step selection functions. We also quantified the consequences of these behaviors for deer survival. Deer reacted differently at day and at night, but avoided high-risk areas proactively during the day and at night in the summer. During a predator encounter, deer increased avoidance of high-risk areas at night but not during the day. Thus, roe deer exhibited a behavioral response race that involved temporally and spatially varying tradeoffs with environmental constraints. We found evidence that nonconsumptive effects of lynx predation risk reduced deer survival and that survival was more sensitive to variation in nonconsumptive effects of lynx than to variation in human proximity. Our findings highlight that nonconsumptive effects may depend on the spatiotemporal distribution of risks and the environmental context, and we discuss how human factors contribute to predator'prey dynamics in human dominated landscapes. [ABSTRACT FROM AUTHOR]

Many animals can accurately judge fluctuations in predation risk and make behavioral adjustments to reduce their vulnerability to predators. We use alarm-call responses by the arboreal monkey Cebus capucinus to characterize perceived predation risk for 3 distinct predator guilds in a heterogeneous landscape. High-risk areas comprised more mature, evergreen forest. The monkeys perceived reduced risk in the high and middle forest layers, and they loosely adjusted vigilance levels to small-scale spatial variation in perceived risk.Although predation has likely played a central role in the evolution of primate socioecology, we currently lack a thorough understanding of how fine-scale variation in perceived predation risk affects primates’ short-term space use patterns and predator avoidance strategies. We examined the spatial and ecological characteristics of predator encounters, as well as behavioral responses to perceived predation risk, in 5 groups of wild white-faced capuchins (Cebus capucinus) in Costa Rica over a 1.5-year period. Alarm-calling bouts directed at birds were more likely to originate in high forest strata, whereas alarm-calling bouts at snakes and terrestrial quadrupeds were more likely to originate near the ground. Relative risk maps based on the locations of predator encounters revealed that high-risk areas for birds and for all guilds combined consisted of more mature forest, whereas low-risk areas for these predators consisted of relatively younger forest. The animals were most vigilant near the ground, which may reflect greater perceived exposure to snakes and terrestrial predators in lower vertical levels. Incorporating the combined risk function into a predictive model of vigilance behavior improved prediction relative to null models of uniform risk or habitat-specific risk. Our results suggest that capuchin monkeys in this study system perceive reduced predation risk in the high and middle forest layers, and they adjust their vigilance behavior to small-scale spatial variation in perceived risk. [ABSTRACT FROM PUBLISHER]