Diel effects on antipredator behavior: nuanced temporal effects in a dynamic landscape of fear

The landscape of fear concept has proven to be an effective way to visualize the influence of spatial distributions of predation risk on behavior of prey. A “dynamic” model that includes the dimension of time adds to the accuracy (and complexity) of the landscape model. Time may be particularly complex because predators typically have traits that make them most effective at hunting during their primary activity periods. Consequently, prey should benefit by giving their strongest antipredator responses when the predator's typical activity period matches the time of the encounter. We measured the antipredator responses of terrestrial Ozark Zigzag Salamanders (Plethodon angusticlavius) when exposed to substrate markings from 2 different snake predators, nocturnal prairie ring-necked snakes (Diadophis punctatus arnyi) and diurnal Eastern garter snakes (Thamnophis sirtalis sirtalis), as well as to a blank water control during the day and at night. Salamanders responded differently to the type of cue (diurnal snake vs. nocturnal snake vs. control) depending on the time of the encounter. During the day, salamanders responded with a strong flight response (high activity) to the diurnal-typical snake, while the strongest flight/escape response to the nocturnal-typical snake was at night. Edge behavior (thigmotaxis) was higher during the daytime, as predicted for a primarily nocturnal prey species, but the effect of cue treatment on this behavior was not statistically significant. Responses to snake cues were remarkably nuanced, and the knowledge of these nuanced temporal influences enriches our understanding of the landscape of fear for this and likely other species.