Perceptual limits to predation risk assessment in green frog (Rana clamitans) tadpoles

Many prey assess predation risk through information sources that decline in reliability over time (i.e., the information sources indicate a wider range of potential predation risk levels over time until they provide no information about the current predation risk). However, prey may lack the perceptual ability to accurately assess the reliability of ageing information sources. Here, evidence is provided that suggests that green frog (Rana clamitans) tadpoles are unable to assess the age of the chemical cue of predatory larval dragonflies (Anax junius) upon exposure to cue up to 48 h old (but can at 72 h). As a result, tadpoles may overestimate the level of risk when they encounter aged Anax chemical cue, resulting in a disproportionately strong behavioural response. In general, the results suggest that the predation risk assessment of prey depends not only on the objective characteristics of the information source, but also on the perceptual limitations of the prey. Prey may lack the context to accurately assess information sources and may consequently misestimate the actual level of predation risk.