Meeting Abstract
Predator evasion in fish is primarily facilitated by visual detection of a threat. In order to understand how prey fish evade predation, it is crucial to know which visual cue triggers an escape response. Previous work suggests that the cues that are most predictive of escape are the angle subtended on the eye by the edges of the approaching predator (θ) and its rate of change (θ ’ ). We performed two sets of experiments to test which cues predict the timing of an escape response in adult zebrafish. The first experiment found threshold values for θ and θ that best predicted the timing of an escape response in response to a projected black circle that expanded at a variable rate. These results were consistent with a second set of experiments, which exposed fish to a live fish predator (Herichthys cyanoguttatus). This experimental series offers a strong behavioral basis for how zebrafish respond to approaching predators.
