Avoidance learning reduces intricate covariation between boldness and foraging behavior in a generalist predator

Abstract

Many predators avoid unprofitable prey by learning to use visual features of the prey as reliable indicators of quality. Despite a rich literature on avoidance learning, we are still in the process of understanding how individuals might change their behavior towards unprofitable prey as information accumulates, the individual-level variation in avoidance foraging behavior, and whether learning would preserve or reduce this variation. In this study, we investigated how avoidance foraging behavior varied in a generalist lizard predator in relation to sex, population of origin, and boldness and tested the effects of learning on the variation in avoidance foraging behavior. We collected data on boldness and avoidance foraging behavior in individuals from two allopatric populations and compared variation in behavior at the beginning and end of learning experiments, in which individuals were presented with normal- and bitter-tasting prey that also differed consistently in color. We found that even though bitter prey elicited strong negative responses, lizards overall did not avoid consuming fewer such prey with learning. Instead, lizards learned to prioritize on palatable prey as they acquired more information. Our data revealed intricate covariation between boldness and avoidance foraging behavior, and the form of this covariation varied between populations, sex, and prey color. Learning overall reduced individual variation in foraging behavior, as well as the degree of covariation with boldness. Our findings highlighted the nuanced manners in which avoidance foraging behavior might manifest and suggested that learning could quickly mitigate fitness difference due to variation in behavior. Lay SummaryPredators can learn to avoid unprofitable prey using certain visual cues or signals, but avoidance foraging behavior can manifest in more subtle ways than simply "to eat or not to eat". We reported changes in foraging sequence and priority in a generalist lizard predator after learning and found that the nature of these changes depended on sex, population of origin, boldness, and prey color. We also found that learning made individuals more similar in behavior.