Individual differences in exploratory and antipredator behaviour in juvenile smallmouth bass (Micropterus dolomieu)

Abstract

Summary The correlation of individual behaviour in different contexts, known as a behavioural syndrome, constrains the optimization of behaviour within each context. Recent studies reveal that the strength of syndromes differs amongst populations and over individual ontogeny. In this study, exploratory behaviour in an unfamiliar environment and behavioural responses to a simulated predator attack in the presence of food were measured in juvenile smallmouth bass (Micropterus dolomieu). The results revealed a syndrome: individuals who actively explored the unfamiliar environment also behaved more boldly in the presence of the model predator. The syndrome implies a tradeoff between collecting information about one’s environment and risk of a predator attack. Additionally, the results revealed different anti-predator strategies. The simulated predator attack induced a longer period of activity (presumably to disperse away from the predator) by shy individuals, who were also more likely to utilize a refuge, had a longer latency to resume activity and were less likely to resume foraging than bold individuals. Larger conspecifics are the main predators of young-of-year smallmouth bass in the population from which subjects were collected. Predation pressure has been implicated as a cause of behavioral syndromes and the results of this study suggest that cannibalism in high density populations is sufficient to induce behavioural correlations.