Foragers rely on various cues to assess predation risk. Information theory predicts that high certainty cues should be valued more than low certainty cues. We measured the latency of black-capped chickadees ( Poecile atricapillus ) to resume feeding during winter in response to cues that conferred different degrees of certainty about current predation risk: a high certainty visual cue (predator mount) and a lower certainty acoustic cue (conspecific mobbing calls), presented either alone or in combination. As predicted, chickadees took longer to resume feeding after the visual than the acoustic cue, and this effect was greatest under conditions of high starvation risk (i.e. low temperatures). Presenting both cues together produced the same foraging delay as the visual cue alone under low starvation risk, but surprisingly, resulted in lower responses under high starvation risk compared to the visual cue alone. We suggest that this may be due to prey using a form of information updating, whereby differences in the timing of perception of acoustic versus visual cues interacts with energetic constraint to shape perceived risk. Although the sequential perception of cues is likely in a range of decision-making contexts, studies manipulating the order in which cues are perceived are needed to test existing models of multimodal cue integration.

Within species, individuals often show repeatable differences in behaviours, called ‘animal personality’. One behaviour that has been widely studied is how quickly an individual resumes feeding after a disturbance, referred to as boldness or risk-taking. Depending on the mechanism(s) shaping risk-taking behaviour, risk-taking could be positively, negatively, or not associated with differences in overall survival. We studied risk-taking and survival in a population of free-living black-capped chickadees ( Poecile atricapillus ) in which we previously showed repeatable among-individual differences in risk-taking over the course of several months. We found no evidence that variation in risk-taking is associated with differences in annual survival. We suggest that variation in risk-taking is likely shaped by multiple mechanisms simultaneously, such that the net effect on survival is small or null. For example, among-individual differences in energy demand may favour greater risk-taking without imposing an overall mortality cost if higher energy demand covaries with escape flight performance. We propose directions for future work, including using a multi-trait, multi-year approach to study risk-taking, to allow for stronger inferences regarding the mechanisms shaping these behavioural decisions.

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